Initial commit

Stuff in src/linker will get rewritten from scratch eventually, it's all
horrible. But for now focus is getting on shit work.

13 files changed, 4126 insertions, 0 deletions

diff --git a/src/linker/NOTICE b/src/linker/NOTICE
new file mode 100644
index 0000000..c5b1efa
--- /dev/null
+++ b/src/linker/NOTICE
@@ -0,0 +1,190 @@
+
+   Copyright (c) 2005-2008, The Android Open Source Project
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
diff --git a/src/linker/README.TXT b/src/linker/README.TXT
new file mode 100644
index 0000000..f920b97
--- /dev/null
+++ b/src/linker/README.TXT
@@ -0,0 +1,144 @@
+Android Dynamic Linker Design Notes
+===================================
+
+Introduction:
+-------------
+
+This document provides several notes related to the design of the Android
+dynamic linker.
+
+
+Prelinking:
+-----------
+
+System libraries in Android are internally prelinked, which means that
+any internal relocations within them are stripped from the corresponding
+shared object, in order to reduce size and speed up loading.
+
+Such libraries can only be loaded at the very specific virtual memory address
+they have been prelinked to (during the build process). The list of prelinked
+system libraries and their corresponding virtual memory address is found in
+the file:
+
+   build/core/prelink-linux-<arch>.map
+
+It should be updated each time a new system library is added to the
+system.
+
+The prelink step happens at build time, and uses the 'soslim' and 'apriori'
+tools:
+
+  - 'apriori' is the real prelink tool which removes relocations from the
+    shared object, however, it must be given a list of symbols to remove
+    from the file.
+
+  - 'soslim' is used to find symbols in an executable ELF file
+    and generate a list that can be passed to 'apriori'.
+
+By default, these tools are only used to remove internal symbols from
+libraries, though they have been designed to allow more aggressive
+optimizations (e.g. 'global' prelinking and symbol stripping, which
+prevent replacing individual system libraries though).
+
+You can disable prelinking at build time by modifying your Android.mk with
+a line like:
+
+    LOCAL_PRELINK_MODULE := false
+
+
+Initialization and Termination functions:
+-----------------------------------------
+
+The Unix Sys V Binary Interface standard states that an
+executable can have the following entries in its .dynamic
+section:
+
+  DT_INIT
+      Points to the address of an initialization function
+      that must be called when the file is loaded.
+
+  DT_INIT_ARRAY
+      Points to an array of function addresses that must be
+      called, in-order, to perform initialization. Some of
+      the entries in the array can be 0 or -1, and should
+      be ignored.
+
+      Note: this is generally stored in a .init_array section
+
+  DT_INIT_ARRAYSZ
+      The size of the DT_INITARRAY, if any
+
+  DT_FINI
+      Points to the address of a finalization function which
+      must be called when the file is unloaded or the process
+      terminated.
+
+  DT_FINI_ARRAY
+      Same as DT_INITARRAY but for finalizers. Note that the
+      functions must be called in reverse-order though
+
+      Note: this is generally stored in a .fini_array section
+
+  DT_FINI_ARRAYSZ
+      Size of FT_FINIARRAY
+
+  DT_PREINIT_ARRAY
+      An array similar to DT_INIT_ARRAY which must *only* be
+      present in executables, not shared libraries, which contains
+      a list of functions that need to be called before any other
+      initialization function (i.e. DT_INIT and/or DT_INIT_ARRAY)
+      in the executable or any of its libraries.
+
+      Note: this is generally stored in a .preinit_array section
+
+  DT_PREINIT_ARRAYSZ
+      The size of DT_PREINIT_ARRAY
+
+If both a DT_INIT and DT_INITARRAY entry are present, the DT_INIT
+function must be called before the DT_INITARRAY functions.
+
+Consequently, the DT_FINIARRAY must be parsed in reverse order before
+the DT_FINI function, if both are available.
+
+Note that the implementation of static C++ constructors is very
+much processor dependent, and may use different ELF sections.
+
+On the ARM (see "C++ ABI for ARM" document), the static constructors
+must be called explicitly from the DT_INIT_ARRAY, and each one of them
+shall register a destructor by calling the special __eabi_atexit()
+function (provided by the C library). The DT_FINI_ARRAY is not used
+by static C++ destructors.
+
+On x86, the lists of constructors and destructors are placed in special
+sections named ".ctors" and ".dtors", and the DT_INIT / DT_FINI functions
+are in charge of calling them explicitly.
+
+
+Debugging:
+----------
+
+It is possible to enable debug output in the dynamic linker. To do so,
+follow these steps:
+
+1/ Modify the line in Android.mk that says:
+
+    LOCAL_CFLAGS += -DLINKER_DEBUG=0
+
+  Into the following:
+
+    LOCAL_CFLAGS += -DLINKER_DEBUG=1
+
+2/ Force-rebuild the dynamic linker:
+
+    cd bionic/linker
+    mm -B
+
+3/ Rebuild a new system image.
+
+You can increase the verbosity of debug traces by defining the DEBUG
+environment variable to a numeric value from 0 to 2. This will only
+affect new processes being launched.
+
+By default, traces are sent to logcat, with the "linker" tag. You can
+change this to go to stdout instead by setting the definition of
+LINKER_DEBUG_TO_LOG to 0 in "linker_debug.h".
diff --git a/src/linker/bionic_tls.h b/src/linker/bionic_tls.h
new file mode 100644
index 0000000..3907a83
--- /dev/null
+++ b/src/linker/bionic_tls.h
@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#ifndef _SYS_TLS_H
+#define _SYS_TLS_H
+
+#define HAVE_ARM_TLS_REGISTER
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+/** WARNING WARNING WARNING
+ **
+ ** This header file is *NOT* part of the public Bionic ABI/API
+ ** and should not be used/included by user-serviceable parts of
+ ** the system (e.g. applications).
+ **
+ ** It is only provided here for the benefit of the system dynamic
+ ** linker and the OpenGL sub-system (which needs to access the
+ ** pre-allocated slot directly for performance reason).
+ **/
+
+/* maximum number of elements in the TLS array */
+#define BIONIC_TLS_SLOTS            64
+
+/* note that slot 0, called TLS_SLOT_SELF must point to itself.
+ * this is required to implement thread-local storage with the x86
+ * Linux kernel, that reads the TLS from fs:[0], where 'fs' is a
+ * thread-specific segment descriptor...
+ */
+
+/* Well known TLS slots */
+#define TLS_SLOT_SELF               0
+#define TLS_SLOT_THREAD_ID          1
+#define TLS_SLOT_ERRNO              2
+
+#define TLS_SLOT_OPENGL_API         3
+#define TLS_SLOT_OPENGL             4
+
+/* this slot is only used to pass information from the dynamic linker to
+ * libc.so when the C library is loaded in to memory. The C runtime init
+ * function will then clear it. Since its use is extremely temporary,
+ * we reuse an existing location.
+ */
+#define  TLS_SLOT_BIONIC_PREINIT    (TLS_SLOT_ERRNO+1)
+
+/* small technical note: it is not possible to call pthread_setspecific
+ * on keys that are <= TLS_SLOT_MAX_WELL_KNOWN, which is why it is set to
+ * TLS_SLOT_ERRNO.
+ *
+ * later slots like TLS_SLOT_OPENGL are pre-allocated through the use of
+ * TLS_DEFAULT_ALLOC_MAP. this means that there is no need to use
+ * pthread_key_create() to initialize them. on the other hand, there is
+ * no destructor associated to them (we might need to implement this later)
+ */
+#define TLS_SLOT_MAX_WELL_KNOWN     TLS_SLOT_ERRNO
+
+#define TLS_DEFAULT_ALLOC_MAP       0x0000001F
+
+/* set the Thread Local Storage, must contain at least BIONIC_TLS_SLOTS pointers */
+extern void __init_tls(void**  tls, void*  thread_info);
+
+/* syscall only, do not call directly */
+extern int __set_tls(void *ptr);
+
+/* get the TLS */
+#ifdef __arm__
+/* The standard way to get the TLS is to call a kernel helper
+ * function (i.e. a function provided at a fixed address in a
+ * "magic page" mapped in all user-space address spaces ), which
+ * contains the most appropriate code path for the target device.
+ *
+ * However, for performance reasons, we're going to use our own
+ * machine code for the system's C shared library.
+ *
+ * We cannot use this optimization in the static version of the
+ * C library, because we don't know where the corresponding code
+ * is going to run.
+ */
+#  ifdef LIBC_STATIC
+
+/* Use the kernel helper in static C library. */
+  typedef volatile void* (__kernel_get_tls_t)(void);
+#    define __get_tls() (*(__kernel_get_tls_t *)0xffff0fe0)()
+
+#  else /* !LIBC_STATIC */
+/* Use optimized code path.
+ * Note that HAVE_ARM_TLS_REGISTER is build-specific
+ * (it must match your kernel configuration)
+ */
+#    ifdef HAVE_ARM_TLS_REGISTER
+ /* We can read the address directly from a coprocessor
+  * register, which avoids touching the data cache
+  * completely.
+  */
+#      define __get_tls() \
+    ({ register unsigned int __val asm("r0"); \
+       asm ("mrc p15, 0, r0, c13, c0, 3" : "=r"(__val) ); \
+       (volatile void*)__val; })
+#    else /* !HAVE_ARM_TLS_REGISTER */
+ /* The kernel provides the address of the TLS at a fixed
+  * address of the magic page too.
+  */
+#      define __get_tls() ( *((volatile void **) 0xffff0ff0) )
+#    endif
+#  endif /* !LIBC_STATIC */
+#else /* !ARM */
+extern void*  __get_tls( void );
+#endif /* !ARM */
+
+/* return the stack base and size, used by our malloc debugger */
+extern void*  __get_stack_base(int  *p_stack_size);
+
+__END_DECLS
+
+#endif /* _SYS_TLS_H */
diff --git a/src/linker/dlfcn.c b/src/linker/dlfcn.c
new file mode 100644
index 0000000..3f76e92
--- /dev/null
+++ b/src/linker/dlfcn.c
@@ -0,0 +1,333 @@
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <dlfcn.h>
+#include <pthread.h>
+#include <time.h>
+#include <stdio.h>
+#include <string.h>
+#include "linker.h"
+#include "linker_format.h"
+
+/* for apkenv_get_hooked_symbol */
+// #include "../compat/hooks.h"
+
+/* for create_wrapper */
+// #include "../debug/wrappers.h"
+
+#include "linker_debug.h"
+
+#ifdef APKENV_DEBUG
+#  define LINKER_DEBUG_PRINTF(...) PRINT(__VA_ARGS__)
+#else
+#  define LINKER_DEBUG_PRINTF(...)
+#endif
+/* This file hijacks the symbols stubbed out in libdl.so. */
+
+#define DL_SUCCESS                    0
+#define DL_ERR_CANNOT_LOAD_LIBRARY    1
+#define DL_ERR_INVALID_LIBRARY_HANDLE 2
+#define DL_ERR_BAD_SYMBOL_NAME        3
+#define DL_ERR_SYMBOL_NOT_FOUND       4
+#define DL_ERR_SYMBOL_NOT_GLOBAL      5
+
+static char dl_err_buf[1024];
+static const char *dl_err_str;
+
+static const char *dl_errors[] = {
+    [DL_ERR_CANNOT_LOAD_LIBRARY] = "Cannot load library",
+    [DL_ERR_INVALID_LIBRARY_HANDLE] = "Invalid library handle",
+    [DL_ERR_BAD_SYMBOL_NAME] = "Invalid symbol name",
+    [DL_ERR_SYMBOL_NOT_FOUND] = "Symbol not found",
+    [DL_ERR_SYMBOL_NOT_GLOBAL] = "Symbol is not global",
+};
+
+#define likely(expr)   __builtin_expect (expr, 1)
+#define unlikely(expr) __builtin_expect (expr, 0)
+
+pthread_mutex_t apkenv_dl_lock = PTHREAD_MUTEX_INITIALIZER;
+
+static void set_dlerror(int err)
+{
+    format_buffer(dl_err_buf, sizeof(dl_err_buf), "%s: %s", dl_errors[err],
+             apkenv_linker_get_error());
+    dl_err_str = (const char *)&dl_err_buf[0];
+}
+
+void *apkenv_android_dlopen(const char *filename, int flag)
+{
+    soinfo *ret;
+
+    pthread_mutex_lock(&apkenv_dl_lock);
+    ret = apkenv_find_library(filename);
+
+    if (unlikely(ret == NULL)) {
+        set_dlerror(DL_ERR_CANNOT_LOAD_LIBRARY);
+    } else {
+        apkenv_call_constructors_recursive(ret);
+        ret->refcount++;
+    }
+    pthread_mutex_unlock(&apkenv_dl_lock);
+    return ret;
+}
+
+static void *apkenv_android_dlopen_wrap(const char *filename, int flag)
+{
+#if 0
+    void *ret = get_builtin_lib_handle(filename);
+    if (ret)
+        return ret;
+#endif
+
+    return apkenv_android_dlopen(filename, flag);
+}
+
+const char *apkenv_android_dlerror(void)
+{
+    const char *tmp = dl_err_str;
+    dl_err_str = NULL;
+    return (const char *)tmp;
+}
+
+enum {
+    WRAPPER_DYNHOOK,
+};
+
+void *apkenv_android_dlsym(void *handle, const char *symbol)
+{
+    soinfo *found;
+    Elf32_Sym *sym;
+    unsigned bind;
+
+    pthread_mutex_lock(&apkenv_dl_lock);
+
+    if(unlikely(handle == 0)) {
+        set_dlerror(DL_ERR_INVALID_LIBRARY_HANDLE);
+        goto err;
+    }
+    if(unlikely(symbol == 0)) {
+        set_dlerror(DL_ERR_BAD_SYMBOL_NAME);
+        goto err;
+    }
+
+#if 0
+    void *sym_addr;
+    if(0 != (sym_addr = apkenv_get_hooked_symbol_dlfcn(handle, symbol)))
+    {
+        LINKER_DEBUG_PRINTF("symbol %s hooked to %x\n",symbol,sym_addr);
+        pthread_mutex_unlock(&apkenv_dl_lock);
+        return sym_addr;
+    }
+
+    if (is_builtin_lib_handle(handle)) {
+        /* must be hooked.. */
+        set_dlerror(DL_ERR_SYMBOL_NOT_FOUND);
+        goto err;
+    }
+#endif
+
+    if(handle == RTLD_DEFAULT) {
+        sym = apkenv_lookup(symbol, &found, NULL);
+    } else if(handle == RTLD_NEXT) {
+        void *ret_addr = __builtin_return_address(0);
+        soinfo *si = apkenv_find_containing_library(ret_addr);
+
+        sym = NULL;
+        if(si && si->next) {
+            sym = apkenv_lookup(symbol, &found, si->next);
+        }
+    } else {
+        found = (soinfo*)handle;
+        sym = apkenv_lookup_in_library(found, symbol);
+    }
+
+    if(likely(sym != 0)) {
+        bind = ELF32_ST_BIND(sym->st_info);
+
+        if(likely((bind == STB_GLOBAL) && (sym->st_shndx != 0))) {
+            unsigned ret = sym->st_value + found->base;
+            pthread_mutex_unlock(&apkenv_dl_lock);
+            return create_wrapper((char*)symbol, (void*)ret, WRAPPER_DYNHOOK);
+        }
+
+        set_dlerror(DL_ERR_SYMBOL_NOT_GLOBAL);
+    }
+    else
+        set_dlerror(DL_ERR_SYMBOL_NOT_FOUND);
+
+err:
+    LINKER_DEBUG_PRINTF("symbol %s has not been hooked\n",symbol);
+    pthread_mutex_unlock(&apkenv_dl_lock);
+    return 0;
+}
+
+int apkenv_android_dladdr(const void *addr, Dl_info *info)
+{
+    int ret = 0;
+
+    pthread_mutex_lock(&apkenv_dl_lock);
+
+    /* Determine if this address can be found in any library currently mapped */
+    soinfo *si = apkenv_find_containing_library(addr);
+
+    if(si) {
+        memset(info, 0, sizeof(*info));
+
+        info->dli_fname = si->name;
+        info->dli_fbase = (void*)(uintptr_t)si->base;
+
+        /* Determine if any symbol in the library contains the specified address */
+        Elf32_Sym *sym = apkenv_find_containing_symbol(addr, si);
+
+        if(sym != NULL) {
+            info->dli_sname = si->strtab + sym->st_name;
+            info->dli_saddr = (void*)(uintptr_t)(si->base + sym->st_value);
+        }
+
+        ret = 1;
+    }
+
+    pthread_mutex_unlock(&apkenv_dl_lock);
+
+    return ret;
+}
+
+int apkenv_android_dlclose(void *handle)
+{
+#if 0
+    if (is_builtin_lib_handle(handle))
+        return 0;
+#endif
+
+    pthread_mutex_lock(&apkenv_dl_lock);
+    (void)apkenv_unload_library((soinfo*)handle);
+    pthread_mutex_unlock(&apkenv_dl_lock);
+    return 0;
+}
+
+
+#if defined(ANDROID_ARM_LINKER)
+//                     0000000 00011111 111112 22222222 2333333 333344444444445555555
+//                     0123456 78901234 567890 12345678 9012345 678901234567890123456
+#define ANDROID_LIBDL_STRTAB \
+                      "dlopen\0dlclose\0dlsym\0dlerror\0dladdr\0dl_unwind_find_exidx\0"
+
+_Unwind_Ptr apkenv_android_dl_unwind_find_exidx(_Unwind_Ptr pc, int *pcount);
+
+#elif defined(ANDROID_X86_LINKER)
+//                     0000000 00011111 111112 22222222 2333333 3333444444444455
+//                     0123456 78901234 567890 12345678 9012345 6789012345678901
+#define ANDROID_LIBDL_STRTAB \
+                      "dlopen\0dlclose\0dlsym\0dlerror\0dladdr\0dl_iterate_phdr\0"
+int
+apkenv_android_dl_iterate_phdr(int (*cb)(struct dl_phdr_info *info, size_t size, void *data),
+                void *data);
+
+#else
+#error Unsupported architecture. Only ARM and x86 are presently supported.
+#endif
+
+static Elf32_Sym apkenv_libdl_symtab[7];
+
+/* Fake out a hash table with a single bucket.
+ * A search of the hash table will look through
+ * apkenv_libdl_symtab starting with index [1], then
+ * use apkenv_libdl_chains to find the next index to
+ * look at.  apkenv_libdl_chains should be set up to
+ * walk through every element in apkenv_libdl_symtab,
+ * and then end with 0 (sentinel value).
+ *
+ * I.e., apkenv_libdl_chains should look like
+ * { 0, 2, 3, ... N, 0 } where N is the number
+ * of actual symbols, or nelems(apkenv_libdl_symtab)-1
+ * (since the first element of apkenv_libdl_symtab is not
+ * a real symbol).
+ *
+ * (see _elf_lookup())
+ *
+ * Note that adding any new symbols here requires
+ * stubbing them out in libdl.
+ */
+static unsigned apkenv_libdl_buckets[1] = { 1 };
+static unsigned apkenv_libdl_chains[7] = { 0, 2, 3, 4, 5, 6, 0 };
+
+soinfo apkenv_libdl_info = {
+  .name = "libdl.so",
+  .flags = FLAG_LINKED,
+
+  .strtab = ANDROID_LIBDL_STRTAB,
+  .symtab = apkenv_libdl_symtab,
+
+  .nbucket = 1,
+  .nchain = 7,
+  .bucket = apkenv_libdl_buckets,
+  .chain = apkenv_libdl_chains,
+};
+
+__attribute__((constructor))
+void
+construct(void)
+{
+  const Elf32_Sym symtab[sizeof(apkenv_libdl_symtab) / sizeof(apkenv_libdl_symtab[0])] = {
+    // total length of apkenv_libdl_info.strtab, including trailing 0
+    // This is actually the the STH_UNDEF entry. Technically, it's
+    // supposed to have st_name == 0, but instead, it points to an index
+    // in the strtab with a \0 to make iterating through the symtab easier.
+    {
+      .st_name = sizeof(ANDROID_LIBDL_STRTAB) - 1,
+    }, {
+      .st_name = 0,   // starting index of the name in apkenv_libdl_info.strtab
+      .st_value = (Elf32_Addr)(uintptr_t)apkenv_android_dlopen_wrap,
+      .st_info = STB_GLOBAL << 4,
+      .st_shndx = 1,
+    }, {
+      .st_name = 7,
+      .st_value = (Elf32_Addr)(uintptr_t)apkenv_android_dlclose,
+      .st_info = STB_GLOBAL << 4,
+      .st_shndx = 1,
+    }, {
+      .st_name = 15,
+      .st_value = (Elf32_Addr)(uintptr_t)apkenv_android_dlsym,
+      .st_info = STB_GLOBAL << 4,
+      .st_shndx = 1,
+    }, {
+      .st_name = 21,
+      .st_value = (Elf32_Addr)(uintptr_t)apkenv_android_dlerror,
+      .st_info = STB_GLOBAL << 4,
+      .st_shndx = 1,
+    }, {
+      .st_name = 29,
+      .st_value = (Elf32_Addr)(uintptr_t)apkenv_android_dladdr,
+      .st_info = STB_GLOBAL << 4,
+      .st_shndx = 1,
+    },
+#ifdef ANDROID_ARM_LINKER
+    {
+      .st_name = 36,
+      .st_value = (Elf32_Addr)(uintptr_t)apkenv_android_dl_unwind_find_exidx,
+      .st_info = STB_GLOBAL << 4,
+      .st_shndx = 1,
+    },
+#elif defined(ANDROID_X86_LINKER)
+    {
+      .st_name = 36,
+      .st_value = (Elf32_Addr)(uintptr_t)apkenv_android_dl_iterate_phdr,
+      .st_info = STB_GLOBAL << 4,
+      .st_shndx = 1,
+    },
+#endif
+  };
+  memcpy(apkenv_libdl_symtab, symtab, sizeof(symtab));
+}
diff --git a/src/linker/linker.c b/src/linker/linker.c
new file mode 100644
index 0000000..8f95472
--- /dev/null
+++ b/src/linker/linker.c
@@ -0,0 +1,2541 @@
+/*
+ * Copyright (C) 2008, 2009 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifdef APKENV_DEBUG
+#  define LINKER_DEBUG_PRINTF(...) PRINT(__VA_ARGS__)
+#else
+#  define LINKER_DEBUG_PRINTF(...)
+#endif
+
+
+#include <linux/auxvec.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <dlfcn.h>
+#include <sys/stat.h>
+#include <assert.h>
+
+#include <pthread.h>
+
+#include <sys/mman.h>
+
+/* special private C library header - see Android.mk */
+#include "bionic_tls.h"
+
+#include "strlcpy.h"
+
+/* for apkenv_get_hooked_symbol */
+// #include "../compat/hooks.h"
+/* for create_wrapper */
+// #include "../debug/wrappers.h"
+
+#include "linker.h"
+#include "linker_debug.h"
+#include "linker_environ.h"
+#include "linker_format.h"
+
+#define ALLOW_SYMBOLS_FROM_MAIN 1
+#define SO_MAX 128
+
+/* Assume average path length of 64 and max 8 paths */
+#define LDPATH_BUFSIZE 512
+#define LDPATH_MAX 8
+
+#define LDPRELOAD_BUFSIZE 512
+#define LDPRELOAD_MAX 8
+
+/* >>> IMPORTANT NOTE - READ ME BEFORE MODIFYING <<<
+ *
+ * Do NOT use malloc() and friends or pthread_*() code here.
+ * Don't use printf() either; it's caused mysterious memory
+ * corruption in the past.
+ * The linker runs before we bring up libc and it's easiest
+ * to make sure it does not depend on any complex libc features
+ *
+ * open issues / todo:
+ *
+ * - are we doing everything we should for ARM_COPY relocations?
+ * - cleaner error reporting
+ * - after linking, set as much stuff as possible to READONLY
+ *   and NOEXEC
+ * - linker hardcodes PAGE_SIZE and PAGE_MASK because the kernel
+ *   headers provide versions that are negative...
+ * - allocate space for soinfo structs dynamically instead of
+ *   having a hard limit (64)
+*/
+
+
+static int apkenv_link_image(soinfo *si, unsigned wr_offset);
+
+static int apkenv_socount = 0;
+static soinfo apkenv_sopool[SO_MAX];
+static soinfo *apkenv_freelist = NULL;
+static soinfo *apkenv_solist = &apkenv_libdl_info;
+static soinfo *apkenv_sonext = &apkenv_libdl_info;
+#if ALLOW_SYMBOLS_FROM_MAIN
+static soinfo *apkenv_somain; /* main process, always the one after apkenv_libdl_info */
+#endif
+
+
+static inline int apkenv_validate_soinfo(soinfo *si)
+{
+    return (si >= apkenv_sopool && si < apkenv_sopool + SO_MAX) ||
+        si == &apkenv_libdl_info;
+}
+
+static char apkenv_ldpaths_buf[LDPATH_BUFSIZE];
+static const char *apkenv_ldpaths[LDPATH_MAX + 1];
+
+static char apkenv_ldpreloads_buf[LDPRELOAD_BUFSIZE];
+static const char *apkenv_ldpreload_names[LDPRELOAD_MAX + 1];
+
+static soinfo *apkenv_preloads[LDPRELOAD_MAX + 1];
+
+#if LINKER_DEBUG
+int apkenv_debug_verbosity = 5;
+#endif
+
+static int apkenv_pid;
+
+/* This boolean is set if the program being loaded is setuid */
+static int apkenv_program_is_setuid;
+
+#if STATS
+struct _link_stats apkenv_linker_stats;
+#endif
+
+#if COUNT_PAGES
+unsigned apkenv_bitmask[4096];
+#endif
+
+#ifndef PT_ARM_EXIDX
+#define PT_ARM_EXIDX    0x70000001      /* .ARM.exidx segment */
+#endif
+
+static char apkenv_tmp_err_buf[768];
+static char apkenv___linker_dl_err_buf[768];
+#define DL_ERR(fmt, x...)                                                     \
+    do {                                                                      \
+        format_buffer(apkenv___linker_dl_err_buf, sizeof(apkenv___linker_dl_err_buf),            \
+                 "%s[%d]: " fmt, __func__, __LINE__, ##x);                    \
+        ERROR(fmt "\n", ##x);                                                      \
+    } while(0)
+
+const char *apkenv_linker_get_error(void)
+{
+    return (const char *)&apkenv___linker_dl_err_buf[0];
+}
+
+enum {
+    WRAPPER_DYNHOOK,
+    WRAPPER_THUMB_INJECTION,
+    WRAPPER_UNHOOKED,
+    WRAPPER_ARM_INJECTION,
+};
+
+static void
+trace(const char *const symbol)
+{
+    printf("trace: %s\n", symbol);
+}
+
+__asm__(
+    "wrapper_start: nop\n"
+    "wrapper_symbol: pushl $0xFAFBFCFD\n"
+    "wrapper_trace: movl $0xFAFBFCFD, %eax\ncall *%eax\npop %eax\n"
+    "wrapper_call: movl $0xFAFBFCFD, %eax\njmp *%eax\n"
+    "wrapper_end: nop\n"
+);
+
+extern char wrapper_start, wrapper_symbol, wrapper_trace, wrapper_call, wrapper_end;
+
+void*
+create_wrapper(const char *const symbol, void *function, int wrapper_type)
+{
+    const size_t sz = &wrapper_end - &wrapper_start;
+    unsigned char *fun = mmap(NULL, sz, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+    assert(fun != MAP_FAILED);
+    memcpy(fun, &wrapper_start, sz);
+    memcpy(fun + (&wrapper_symbol - &wrapper_start) + 1, &symbol, sizeof(symbol));
+    memcpy(fun + (&wrapper_trace - &wrapper_start) + 1, (uintptr_t[]){ (uintptr_t)trace }, sizeof(uintptr_t));
+    memcpy(fun + (&wrapper_call - &wrapper_start) + 1, &function, sizeof(function));
+    mprotect(fun, sz, PROT_READ | PROT_EXEC);
+    return fun;
+}
+
+/*
+ * This function is an empty stub where GDB locates a breakpoint to get notified
+ * about linker activity.
+ */
+//extern void __attribute__((noinline)) rtld_db_dlactivity(void);
+
+//static struct r_debug _r_debug = {1, NULL, &rtld_db_dlactivity,
+//                                  RT_CONSISTENT, 0};
+/* apkenv */
+#define rtld_db_dlactivity() ((void (*)(void))_r_debug.r_brk)()
+
+static struct link_map *apkenv_r_debug_head, *apkenv_r_debug_tail;
+
+static pthread_mutex_t apkenv__r_debug_lock = PTHREAD_MUTEX_INITIALIZER;
+
+static void apkenv_insert_soinfo_into_debug_map(soinfo * info)
+{
+    struct link_map * map;
+
+    /* Copy the necessary fields into the debug structure.
+     */
+    map = &(info->linkmap);
+    map->l_addr = info->base;
+    map->l_name = info->fullpath;
+    map->l_ld = (void *)info->dynamic;
+
+    /* Stick the new library at the end of the list.
+     * gdb tends to care more about libc than it does
+     * about leaf libraries, and ordering it this way
+     * reduces the back-and-forth over the wire.
+     */
+    if (apkenv_r_debug_tail) {
+        apkenv_r_debug_tail->l_next = map;
+        map->l_prev = apkenv_r_debug_tail;
+        map->l_next = 0;
+    } else {
+        /* apkenv: for sending to gdb */
+        apkenv_r_debug_head = map;
+        map->l_prev = 0;
+        map->l_next = 0;
+    }
+    apkenv_r_debug_tail = map;
+}
+
+static void apkenv_remove_soinfo_from_debug_map(soinfo * info)
+{
+    struct link_map * map = &(info->linkmap);
+
+    if (apkenv_r_debug_tail == map)
+        apkenv_r_debug_tail = map->l_prev;
+
+    if (map->l_prev) map->l_prev->l_next = map->l_next;
+    if (map->l_next) map->l_next->l_prev = map->l_prev;
+}
+
+void apkenv_notify_gdb_of_libraries(void);
+
+static void apkenv_notify_gdb_of_load(soinfo * info)
+{
+    if (info->flags & FLAG_EXE) {
+        // GDB already knows about the main executable
+        return;
+    }
+
+    pthread_mutex_lock(&apkenv__r_debug_lock);
+
+    _r_debug.r_state = RT_ADD;
+    rtld_db_dlactivity();
+
+    apkenv_insert_soinfo_into_debug_map(info);
+
+    _r_debug.r_state = RT_CONSISTENT;
+    rtld_db_dlactivity();
+
+    apkenv_notify_gdb_of_libraries();
+    pthread_mutex_unlock(&apkenv__r_debug_lock);
+}
+
+static void apkenv_notify_gdb_of_unload(soinfo * info)
+{
+    if (info->flags & FLAG_EXE) {
+        // GDB already knows about the main executable
+        return;
+    }
+
+    pthread_mutex_lock(&apkenv__r_debug_lock);
+
+    _r_debug.r_state = RT_DELETE;
+    rtld_db_dlactivity();
+
+    apkenv_remove_soinfo_from_debug_map(info);
+
+    _r_debug.r_state = RT_CONSISTENT;
+    rtld_db_dlactivity();
+
+    apkenv_notify_gdb_of_libraries();
+    pthread_mutex_unlock(&apkenv__r_debug_lock);
+}
+
+void apkenv_notify_gdb_of_libraries(void)
+{
+    struct link_map *tmap = _r_debug.r_map;
+    while (tmap->l_next != NULL)
+        tmap = tmap->l_next;
+
+    _r_debug.r_state = RT_ADD;
+    rtld_db_dlactivity();
+
+    /* append android libs before notifying gdb */
+    tmap->l_next = apkenv_r_debug_head;
+    apkenv_r_debug_head->l_prev = tmap;
+
+    _r_debug.r_state = RT_CONSISTENT;
+    rtld_db_dlactivity();
+
+    /* restore so that ld-linux doesn't freak out */
+    tmap->l_next = NULL;
+}
+
+static soinfo *apkenv_alloc_info(const char *name)
+{
+    soinfo *si;
+
+    if(strlen(name) >= SOINFO_NAME_LEN) {
+        DL_ERR("%5d library name %s too long", apkenv_pid, name);
+        return NULL;
+    }
+
+    /* The apkenv_freelist is populated when we call apkenv_free_info(), which in turn is
+       done only by dlclose(), which is not likely to be used.
+    */
+    if (!apkenv_freelist) {
+        if(apkenv_socount == SO_MAX) {
+            DL_ERR("%5d too many libraries when loading %s", apkenv_pid, name);
+            return NULL;
+        }
+        apkenv_freelist = apkenv_sopool + apkenv_socount++;
+        apkenv_freelist->next = NULL;
+    }
+
+    si = apkenv_freelist;
+    apkenv_freelist = apkenv_freelist->next;
+
+    /* Make sure we get a clean block of soinfo */
+    memset(si, 0, sizeof(soinfo));
+    apkenv_strlcpy((char*) si->name, name, sizeof(si->name));
+    apkenv_sonext->next = si;
+    si->next = NULL;
+    si->refcount = 0;
+    apkenv_sonext = si;
+
+    TRACE("%5d name %s: allocated soinfo @ %p\n", apkenv_pid, name, si);
+    return si;
+}
+
+static void apkenv_free_info(soinfo *si)
+{
+    soinfo *prev = NULL, *trav;
+
+    TRACE("%5d name %s: freeing soinfo @ %p\n", apkenv_pid, si->name, si);
+
+    for(trav = apkenv_solist; trav != NULL; trav = trav->next){
+        if (trav == si)
+            break;
+        prev = trav;
+    }
+    if (trav == NULL) {
+        /* si was not ni apkenv_solist */
+        DL_ERR("%5d name %s is not in apkenv_solist!", apkenv_pid, si->name);
+        return;
+    }
+
+    /* prev will never be NULL, because the first entry in apkenv_solist is
+       always the static apkenv_libdl_info.
+    */
+    prev->next = si->next;
+    if (si == apkenv_sonext) apkenv_sonext = prev;
+    si->next = apkenv_freelist;
+    apkenv_freelist = si;
+}
+
+static const char *apkenv_addr_to_name(unsigned addr)
+{
+    soinfo *si;
+
+    for(si = apkenv_solist; si != 0; si = si->next){
+        if((addr >= si->base) && (addr < (si->base + si->size))) {
+            return si->name;
+        }
+    }
+
+    return "";
+}
+
+/* For a given PC, find the .so that it belongs to.
+ * Returns the base address of the .ARM.exidx section
+ * for that .so, and the number of 8-byte entries
+ * in that section (via *pcount).
+ *
+ * Intended to be called by libc's __gnu_Unwind_Find_exidx().
+ *
+ * This function is exposed via dlfcn.c and libdl.so.
+ */
+#ifdef ANDROID_ARM_LINKER
+_Unwind_Ptr apkenv_android_dl_unwind_find_exidx(_Unwind_Ptr pc, int *pcount)
+{
+    soinfo *si;
+    unsigned addr = (unsigned)pc;
+
+    for (si = apkenv_solist; si != 0; si = si->next){
+        if ((addr >= si->base) && (addr < (si->base + si->size))) {
+            *pcount = si->ARM_exidx_count;
+            return (_Unwind_Ptr)(si->base + (unsigned long)si->ARM_exidx);
+        }
+    }
+   *pcount = 0;
+    return NULL;
+}
+#elif defined(ANDROID_X86_LINKER)
+/* Here, we only have to provide a callback to iterate across all the
+ * loaded libraries. gcc_eh does the rest. */
+int
+apkenv_android_dl_iterate_phdr(int (*cb)(struct dl_phdr_info *info, size_t size, void *data),
+                void *data)
+{
+    soinfo *si;
+    struct dl_phdr_info dl_info;
+    int rv = 0;
+
+    for (si = apkenv_solist; si != NULL; si = si->next) {
+        dl_info.dlpi_addr = si->linkmap.l_addr;
+        dl_info.dlpi_name = si->linkmap.l_name;
+        dl_info.dlpi_phdr = (void*)si->phdr;
+        dl_info.dlpi_phnum = si->phnum;
+        rv = cb(&dl_info, sizeof (struct dl_phdr_info), data);
+        if (rv != 0)
+            break;
+    }
+    return rv;
+}
+#endif
+
+static Elf32_Sym *apkenv__elf_lookup(soinfo *si, unsigned hash, const char *name)
+{
+    Elf32_Sym *s;
+    Elf32_Sym *symtab = si->symtab;
+    const char *strtab = si->strtab;
+    unsigned n;
+
+    TRACE_TYPE(LOOKUP, "%5d SEARCH %s in %s@0x%08x %08x %d\n", apkenv_pid,
+               name, si->name, si->base, hash, hash % si->nbucket);
+    if (si->nbucket == 0) {
+        return NULL;
+    }
+    n = hash % si->nbucket;
+
+    for(n = si->bucket[hash % si->nbucket]; n != 0; n = si->chain[n]){
+        s = symtab + n;
+        if(strcmp(strtab + s->st_name, name)) continue;
+
+            /* only concern ourselves with global and weak symbol definitions */
+        switch(ELF32_ST_BIND(s->st_info)){
+        case STB_GLOBAL:
+        case STB_WEAK:
+                /* no section == undefined */
+            if(s->st_shndx == 0) continue;
+
+            TRACE_TYPE(LOOKUP, "%5d FOUND %s in %s (%08x) %d\n", apkenv_pid,
+                       name, si->name, s->st_value, s->st_size);
+            return s;
+        }
+    }
+
+    return NULL;
+}
+
+static unsigned apkenv_elfhash(const char *_name)
+{
+    const unsigned char *name = (const unsigned char *) _name;
+    unsigned h = 0, g;
+
+    while(*name) {
+        h = (h << 4) + *name++;
+        g = h & 0xf0000000;
+        h ^= g;
+        h ^= g >> 24;
+    }
+    return h;
+}
+
+const char *apkenv_last_library_used = NULL;
+
+static Elf32_Sym *
+apkenv__do_lookup(soinfo *si, const char *name, unsigned *base)
+{
+    unsigned elf_hash = apkenv_elfhash(name);
+    Elf32_Sym *s;
+    unsigned *d;
+    soinfo *lsi = si;
+    int i;
+
+    /* Look for symbols in the local scope (the object who is
+     * searching). This happens with C++ templates on i386 for some
+     * reason.
+     *
+     * Notes on weak symbols:
+     * The ELF specs are ambigious about treatment of weak definitions in
+     * dynamic linking.  Some systems return the first definition found
+     * and some the first non-weak definition.   This is system dependent.
+     * Here we return the first definition found for simplicity.  */
+
+    s = apkenv__elf_lookup(si, elf_hash, name);
+    if(s != NULL)
+        goto done;
+
+    /* Next, look for it in the apkenv_preloads list */
+    for(i = 0; apkenv_preloads[i] != NULL; i++) {
+        lsi = apkenv_preloads[i];
+        s = apkenv__elf_lookup(lsi, elf_hash, name);
+        if(s != NULL)
+            goto done;
+    }
+
+    for(d = si->dynamic; *d; d += 2) {
+        if(d[0] == DT_NEEDED){
+            lsi = (soinfo *)d[1];
+            if (!apkenv_validate_soinfo(lsi)) {
+                DL_ERR("%5d bad DT_NEEDED pointer in %s",
+                       apkenv_pid, si->name);
+                return NULL;
+            }
+
+            DEBUG("%5d %s: looking up %s in %s\n",
+                  apkenv_pid, si->name, name, lsi->name);
+            s = apkenv__elf_lookup(lsi, elf_hash, name);
+            if ((s != NULL) && (s->st_shndx != SHN_UNDEF))
+                goto done;
+        }
+    }
+
+#if ALLOW_SYMBOLS_FROM_MAIN
+    /* If we are resolving relocations while dlopen()ing a library, it's OK for
+     * the library to resolve a symbol that's defined in the executable itself,
+     * although this is rare and is generally a bad idea.
+     */
+    if (apkenv_somain) {
+        lsi = apkenv_somain;
+        DEBUG("%5d %s: looking up %s in executable %s\n",
+              apkenv_pid, si->name, name, lsi->name);
+        s = apkenv__elf_lookup(lsi, elf_hash, name);
+    }
+#endif
+
+done:
+    if(s != NULL) {
+        TRACE_TYPE(LOOKUP, "%5d si %s sym %s s->st_value = 0x%08x, "
+                   "found in %s, base = 0x%08x\n",
+                   apkenv_pid, si->name, name, s->st_value, lsi->name, lsi->base);
+        apkenv_last_library_used = lsi->name;
+        *base = lsi->base;
+        return s;
+    }
+
+    return NULL;
+}
+
+/* This is used by dl_sym().  It performs symbol lookup only within the
+   specified soinfo object and not in any of its dependencies.
+ */
+Elf32_Sym *apkenv_lookup_in_library(soinfo *si, const char *name)
+{
+    return apkenv__elf_lookup(si, apkenv_elfhash(name), name);
+}
+
+/* This is used by dl_sym().  It performs a global symbol lookup.
+ */
+Elf32_Sym *apkenv_lookup(const char *name, soinfo **found, soinfo *start)
+{
+    unsigned elf_hash = apkenv_elfhash(name);
+    Elf32_Sym *s = NULL;
+    soinfo *si;
+
+    if(start == NULL) {
+        start = apkenv_solist;
+    }
+
+    for(si = start; (s == NULL) && (si != NULL); si = si->next)
+    {
+        if(si->flags & FLAG_ERROR)
+            continue;
+        s = apkenv__elf_lookup(si, elf_hash, name);
+        if (s != NULL) {
+            *found = si;
+            break;
+        }
+    }
+
+    if(s != NULL) {
+        TRACE_TYPE(LOOKUP, "%5d %s s->st_value = 0x%08x, "
+                   "si->base = 0x%08x\n", apkenv_pid, name, s->st_value, si->base);
+        return s;
+    }
+
+    return NULL;
+}
+
+soinfo *apkenv_find_containing_library(const void *addr)
+{
+    soinfo *si;
+
+    for(si = apkenv_solist; si != NULL; si = si->next)
+    {
+        if((unsigned)addr >= si->base && (unsigned)addr - si->base < si->size) {
+            return si;
+        }
+    }
+
+    return NULL;
+}
+
+Elf32_Sym *apkenv_find_containing_symbol(const void *addr, soinfo *si)
+{
+    unsigned int i;
+    unsigned soaddr = (unsigned)addr - si->base;
+
+    /* Search the library's symbol table for any defined symbol which
+     * contains this address */
+    for(i=0; i<si->nchain; i++) {
+        Elf32_Sym *sym = &si->symtab[i];
+
+        if(sym->st_shndx != SHN_UNDEF &&
+           soaddr >= sym->st_value &&
+           soaddr < sym->st_value + sym->st_size) {
+            return sym;
+        }
+    }
+
+    return NULL;
+}
+
+#if 0
+static void dump(soinfo *si)
+{
+    Elf32_Sym *s = si->symtab;
+    unsigned n;
+
+    for(n = 0; n < si->nchain; n++) {
+        TRACE("%5d %04d> %08x: %02x %04x %08x %08x %s\n", apkenv_pid, n, s,
+               s->st_info, s->st_shndx, s->st_value, s->st_size,
+               si->strtab + s->st_name);
+        s++;
+    }
+}
+#endif
+
+#define SOPATH_MAX 8
+
+static const char *apkenv_sopaths[SOPATH_MAX + 1] = {
+    "/vendor/lib",
+    "/system/lib",
+    // APKENV_PREFIX "/lib/" APKENV_TARGET "/bionic/",
+#ifdef APKENV_LOCAL_BIONIC_PATH
+    APKENV_LOCAL_BIONIC_PATH,
+#endif
+};
+
+int apkenv_add_sopath(const char *path)
+{
+    int i;
+    for (i = 0; i < SOPATH_MAX; i++) {
+        if (apkenv_sopaths[i] == NULL) {
+            apkenv_sopaths[i] = path;
+            return 0;
+        }
+
+        if (strcmp(path, apkenv_sopaths[i]) == 0)
+            return 0;
+    }
+
+    ERROR("too many apkenv_sopaths\n");
+    return -1;
+}
+
+static int apkenv__open_lib(const char *name)
+{
+    int fd;
+    struct stat filestat;
+
+    if ((stat(name, &filestat) >= 0) && S_ISREG(filestat.st_mode)) {
+        if ((fd = open(name, O_RDONLY)) >= 0)
+            return fd;
+    }
+
+    return -1;
+}
+
+static int apkenv_open_library(const char *name, char *fullpath)
+{
+    int fd;
+    char buf[512];
+    const char **path;
+    int n;
+
+    TRACE("[ %5d opening %s ]\n", apkenv_pid, name);
+
+    if(name == 0) return -1;
+    if(strlen(name) > 256) return -1;
+
+    strcpy(fullpath, name);
+
+    if ((name[0] == '/') && ((fd = apkenv__open_lib(name)) >= 0))
+        return fd;
+
+    if (((fd = apkenv__open_lib(name)) >= 0))
+        return fd;
+
+    for (path = apkenv_ldpaths; *path; path++) {
+        n = format_buffer(buf, sizeof(buf), "%s/%s", *path, name);
+        if (n < 0 || n >= (int)sizeof(buf)) {
+            WARN("Ignoring very long library path: %s/%s\n", *path, name);
+            continue;
+        }
+        if ((fd = apkenv__open_lib(buf)) >= 0) {
+            strcpy(fullpath, buf);
+            return fd;
+        }
+    }
+    for (path = apkenv_sopaths; *path; path++) {
+        n = format_buffer(buf, sizeof(buf), "%s/%s", *path, name);
+        if (n < 0 || n >= (int)sizeof(buf)) {
+            WARN("Ignoring very long library path: %s/%s\n", *path, name);
+            continue;
+        }
+        if ((fd = apkenv__open_lib(buf)) >= 0) {
+            strcpy(fullpath, buf);
+            return fd;
+        }
+    }
+
+    return -1;
+}
+
+typedef struct {
+    long mmap_addr;
+    char tag[4]; /* 'P', 'R', 'E', ' ' */
+} prelink_info_t;
+
+/* Returns the requested base address if the library is prelinked,
+ * and 0 otherwise.  */
+static unsigned long
+apkenv_is_prelinked(int fd, const char *name)
+{
+    off_t sz;
+    prelink_info_t info;
+
+    sz = lseek(fd, -sizeof(prelink_info_t), SEEK_END);
+    if (sz < 0) {
+        DL_ERR("lseek() failed!");
+        return 0;
+    }
+
+    if (read(fd, &info, sizeof(info)) != sizeof(info)) {
+        WARN("Could not read prelink_info_t structure for `%s`\n", name);
+        return 0;
+    }
+
+    if (strncmp(info.tag, "PRE ", 4)) {
+        WARN("`%s` is not a prelinked library\n", name);
+        return 0;
+    }
+
+    return (unsigned long)info.mmap_addr;
+}
+
+/* apkenv_verify_elf_object
+ *      Verifies if the object @ base is a valid ELF object
+ *
+ * Args:
+ *
+ * Returns:
+ *       0 on success
+ *      -1 if no valid ELF object is found @ base.
+ */
+static int
+apkenv_verify_elf_object(void *base, const char *name)
+{
+    Elf32_Ehdr *hdr = (Elf32_Ehdr *) base;
+
+    if (hdr->e_ident[EI_MAG0] != ELFMAG0) return -1;
+    if (hdr->e_ident[EI_MAG1] != ELFMAG1) return -1;
+    if (hdr->e_ident[EI_MAG2] != ELFMAG2) return -1;
+    if (hdr->e_ident[EI_MAG3] != ELFMAG3) return -1;
+
+    /* TODO: Should we verify anything else in the header? */
+#ifdef ANDROID_ARM_LINKER
+    if (hdr->e_machine != EM_ARM) return -1;
+#elif defined(ANDROID_X86_LINKER)
+    if (hdr->e_machine != EM_386) return -1;
+#endif
+    return 0;
+}
+
+
+/* apkenv_get_lib_extents
+ *      Retrieves the base (*base) address where the ELF object should be
+ *      mapped and its overall memory size (*total_sz).
+ *
+ * Args:
+ *      fd: Opened file descriptor for the library
+ *      name: The name of the library
+ *      _hdr: Pointer to the header page of the library
+ *      total_sz: Total size of the memory that should be allocated for
+ *                this library
+ *
+ * Returns:
+ *      -1 if there was an error while trying to get the lib extents.
+ *         The possible reasons are:
+ *             - Could not determine if the library was prelinked.
+ *             - The library provided is not a valid ELF object
+ *       0 if the library did not request a specific base offset (normal
+ *         for non-prelinked libs)
+ *     > 0 if the library requests a specific address to be mapped to.
+ *         This indicates a pre-linked library.
+ */
+static unsigned
+apkenv_get_lib_extents(int fd, const char *name, void *__hdr, unsigned *total_sz)
+{
+    unsigned req_base;
+    unsigned min_vaddr = 0xffffffff;
+    unsigned max_vaddr = 0;
+    unsigned char *_hdr = (unsigned char *)__hdr;
+    Elf32_Ehdr *ehdr = (Elf32_Ehdr *)_hdr;
+    Elf32_Phdr *phdr;
+    int cnt;
+
+    TRACE("[ %5d Computing extents for '%s'. ]\n", apkenv_pid, name);
+    if (apkenv_verify_elf_object(_hdr, name) < 0) {
+        DL_ERR("%5d - %s is not a valid ELF object", apkenv_pid, name);
+        return (unsigned)-1;
+    }
+
+    req_base = (unsigned) apkenv_is_prelinked(fd, name);
+    if (req_base == (unsigned)-1)
+        return -1;
+    else if (req_base != 0) {
+        TRACE("[ %5d - Prelinked library '%s' requesting base @ 0x%08x ]\n",
+              apkenv_pid, name, req_base);
+    } else {
+        TRACE("[ %5d - Non-prelinked library '%s' found. ]\n", apkenv_pid, name);
+    }
+
+    phdr = (Elf32_Phdr *)(_hdr + ehdr->e_phoff);
+
+    /* find the min/max p_vaddrs from all the PT_LOAD segments so we can
+     * get the range. */
+    for (cnt = 0; cnt < ehdr->e_phnum; ++cnt, ++phdr) {
+        if (phdr->p_type == PT_LOAD) {
+            if ((phdr->p_vaddr + phdr->p_memsz) > max_vaddr)
+                max_vaddr = phdr->p_vaddr + phdr->p_memsz;
+            if (phdr->p_vaddr < min_vaddr)
+                min_vaddr = phdr->p_vaddr;
+        }
+    }
+
+    if ((min_vaddr == 0xffffffff) && (max_vaddr == 0)) {
+        DL_ERR("%5d - No loadable segments found in %s.", apkenv_pid, name);
+        return (unsigned)-1;
+    }
+
+    /* truncate min_vaddr down to page boundary */
+    min_vaddr &= ~PAGE_MASK;
+
+    /* round max_vaddr up to the next page */
+    max_vaddr = (max_vaddr + PAGE_SIZE - 1) & ~PAGE_MASK;
+
+    *total_sz = (max_vaddr - min_vaddr);
+    return (unsigned)req_base;
+}
+
+/* apkenv_reserve_mem_region
+ *
+ *     This function reserves a chunk of memory to be used for mapping in
+ *     a prelinked shared library. We reserve the entire memory region here, and
+ *     then the rest of the linker will relocate the individual loadable
+ *     segments into the correct locations within this memory range.
+ *
+ * Args:
+ *     si->base: The requested base of the allocation.
+ *     si->size: The size of the allocation.
+ *
+ * Returns:
+ *     -1 on failure, and 0 on success.  On success, si->base will contain
+ *     the virtual address at which the library will be mapped.
+ */
+
+static int apkenv_reserve_mem_region(soinfo *si)
+{
+    void *base = mmap((void *)si->base, si->size, PROT_NONE,
+                      MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+    if (base == MAP_FAILED) {
+        DL_ERR("%5d can NOT map (%sprelinked) library '%s' at 0x%08x "
+              "as requested, will try general pool: %d (%s)",
+              apkenv_pid, (si->base ? "" : "non-"), si->name, si->base,
+              errno, strerror(errno));
+        return -1;
+    } else if (base != (void *)si->base) {
+        DL_ERR("OOPS: %5d %sprelinked library '%s' mapped at 0x%08x, "
+              "not at 0x%08x", apkenv_pid, (si->base ? "" : "non-"),
+              si->name, (unsigned)base, si->base);
+        munmap(base, si->size);
+        return -1;
+    }
+    return 0;
+}
+
+static int apkenv_alloc_mem_region(soinfo *si)
+{
+    if (si->base) {
+        /* Attempt to mmap a prelinked library. */
+        return apkenv_reserve_mem_region(si);
+    }
+
+    /* This is not a prelinked library, so we use the kernel's default
+       allocator.
+    */
+
+    void *base = mmap(NULL, si->size, PROT_NONE,
+                      MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+    if (base == MAP_FAILED) {
+        DL_ERR("%5d mmap of library '%s' failed: %d (%s)\n",
+              apkenv_pid, si->name,
+              errno, strerror(errno));
+        goto err;
+    }
+    si->base = (unsigned) base;
+    PRINT("%5d mapped library '%s' to %08x via kernel allocator.\n",
+          apkenv_pid, si->name, si->base);
+    return 0;
+
+err:
+    DL_ERR("OOPS: %5d cannot map library '%s'. no vspace available.",
+          apkenv_pid, si->name);
+    return -1;
+}
+
+#define MAYBE_MAP_FLAG(x,from,to)    (((x) & (from)) ? (to) : 0)
+#define PFLAGS_TO_PROT(x)            (MAYBE_MAP_FLAG((x), PF_X, PROT_EXEC) | \
+                                      MAYBE_MAP_FLAG((x), PF_R, PROT_READ) | \
+                                      MAYBE_MAP_FLAG((x), PF_W, PROT_WRITE))
+/* apkenv_load_segments
+ *
+ *     This function loads all the loadable (PT_LOAD) segments into memory
+ *     at their appropriate memory offsets off the base address.
+ *
+ * Args:
+ *     fd: Open file descriptor to the library to load.
+ *     header: Pointer to a header page that contains the ELF header.
+ *             This is needed since we haven't mapped in the real file yet.
+ *     si: ptr to soinfo struct describing the shared object.
+ *
+ * Returns:
+ *     0 on success, -1 on failure.
+ */
+static int
+apkenv_load_segments(int fd, void *header, soinfo *si)
+{
+    Elf32_Ehdr *ehdr = (Elf32_Ehdr *)header;
+    Elf32_Phdr *phdr = (Elf32_Phdr *)((unsigned char *)header + ehdr->e_phoff);
+    Elf32_Addr base = (Elf32_Addr) si->base;
+    int cnt;
+    unsigned len;
+    Elf32_Addr tmp;
+    unsigned char *pbase;
+    unsigned char *extra_base;
+    unsigned extra_len;
+    unsigned total_sz = 0;
+
+    si->wrprotect_start = 0xffffffff;
+    si->wrprotect_end = 0;
+
+    TRACE("[ %5d - Begin loading segments for '%s' @ 0x%08x ]\n",
+          apkenv_pid, si->name, (unsigned)si->base);
+    /* Now go through all the PT_LOAD segments and map them into memory
+     * at the appropriate locations. */
+    for (cnt = 0; cnt < ehdr->e_phnum; ++cnt, ++phdr) {
+        if (phdr->p_type == PT_LOAD) {
+            DEBUG_DUMP_PHDR(phdr, "PT_LOAD", apkenv_pid);
+            /* we want to map in the segment on a page boundary */
+            tmp = base + (phdr->p_vaddr & (~PAGE_MASK));
+            /* add the # of bytes we masked off above to the total length. */
+            len = phdr->p_filesz + (phdr->p_vaddr & PAGE_MASK);
+
+            TRACE("[ %d - Trying to load segment from '%s' @ 0x%08x "
+                  "(0x%08x). p_vaddr=0x%08x p_offset=0x%08x ]\n", apkenv_pid, si->name,
+                  (unsigned)tmp, len, phdr->p_vaddr, phdr->p_offset);
+            pbase = mmap((void *)tmp, len, PFLAGS_TO_PROT(phdr->p_flags),
+                         MAP_PRIVATE | MAP_FIXED, fd,
+                         phdr->p_offset & (~PAGE_MASK));
+            if (pbase == MAP_FAILED) {
+                DL_ERR("%d failed to map segment from '%s' @ 0x%08x (0x%08x). "
+                      "p_vaddr=0x%08x p_offset=0x%08x", apkenv_pid, si->name,
+                      (unsigned)tmp, len, phdr->p_vaddr, phdr->p_offset);
+                goto fail;
+            }
+
+            /* If 'len' didn't end on page boundary, and it's a writable
+             * segment, zero-fill the rest. */
+            if ((len & PAGE_MASK) && (phdr->p_flags & PF_W))
+                memset((void *)(pbase + len), 0, PAGE_SIZE - (len & PAGE_MASK));
+
+            /* Check to see if we need to extend the map for this segment to
+             * cover the diff between filesz and memsz (i.e. for bss).
+             *
+             *  base           _+---------------------+  page boundary
+             *                  .                     .
+             *                  |                     |
+             *                  .                     .
+             *  pbase          _+---------------------+  page boundary
+             *                  |                     |
+             *                  .                     .
+             *  base + p_vaddr _|                     |
+             *                  . \          \        .
+             *                  . | filesz   |        .
+             *  pbase + len    _| /          |        |
+             *     <0 pad>      .            .        .
+             *  extra_base     _+------------|--------+  page boundary
+             *               /  .            .        .
+             *               |  .            .        .
+             *               |  +------------|--------+  page boundary
+             *  extra_len->  |  |            |        |
+             *               |  .            | memsz  .
+             *               |  .            |        .
+             *               \ _|            /        |
+             *                  .                     .
+             *                  |                     |
+             *                 _+---------------------+  page boundary
+             */
+            tmp = (Elf32_Addr)(((unsigned)pbase + len + PAGE_SIZE - 1) &
+                                    (~PAGE_MASK));
+            if (tmp < (base + phdr->p_vaddr + phdr->p_memsz)) {
+                extra_len = base + phdr->p_vaddr + phdr->p_memsz - tmp;
+                TRACE("[ %5d - Need to extend segment from '%s' @ 0x%08x "
+                      "(0x%08x) ]\n", apkenv_pid, si->name, (unsigned)tmp, extra_len);
+                /* map in the extra page(s) as anonymous into the range.
+                 * This is probably not necessary as we already mapped in
+                 * the entire region previously, but we just want to be
+                 * sure. This will also set the right flags on the region
+                 * (though we can probably accomplish the same thing with
+                 * mprotect).
+                 */
+                extra_base = mmap((void *)tmp, extra_len,
+                                  PFLAGS_TO_PROT(phdr->p_flags),
+                                  MAP_PRIVATE | MAP_FIXED | MAP_ANONYMOUS,
+                                  -1, 0);
+                if (extra_base == MAP_FAILED) {
+                    DL_ERR("[ %5d - failed to extend segment from '%s' @ 0x%08x"
+                           " (0x%08x) ]", apkenv_pid, si->name, (unsigned)tmp,
+                          extra_len);
+                    goto fail;
+                }
+                /* TODO: Check if we need to memset-0 this region.
+                 * Anonymous mappings are zero-filled copy-on-writes, so we
+                 * shouldn't need to. */
+                TRACE("[ %5d - Segment from '%s' extended @ 0x%08x "
+                      "(0x%08x)\n", apkenv_pid, si->name, (unsigned)extra_base,
+                      extra_len);
+            }
+            /* set the len here to show the full extent of the segment we
+             * just loaded, mostly for debugging */
+            len = (((unsigned)base + phdr->p_vaddr + phdr->p_memsz +
+                    PAGE_SIZE - 1) & (~PAGE_MASK)) - (unsigned)pbase;
+            TRACE("[ %5d - Successfully loaded segment from '%s' @ 0x%08x "
+                  "(0x%08x). p_vaddr=0x%08x p_offset=0x%08x\n", apkenv_pid, si->name,
+                  (unsigned)pbase, len, phdr->p_vaddr, phdr->p_offset);
+            total_sz += len;
+            /* Make the section writable just in case we'll have to write to
+             * it during relocation (i.e. text segment). However, we will
+             * remember what range of addresses should be write protected.
+             *
+             */
+            if (!(phdr->p_flags & PF_W)) {
+                if ((unsigned)pbase < si->wrprotect_start)
+                    si->wrprotect_start = (unsigned)pbase;
+                if (((unsigned)pbase + len) > si->wrprotect_end)
+                    si->wrprotect_end = (unsigned)pbase + len;
+                mprotect(pbase, len,
+                         PFLAGS_TO_PROT(phdr->p_flags) | PROT_WRITE);
+            }
+        } else if (phdr->p_type == PT_DYNAMIC) {
+            DEBUG_DUMP_PHDR(phdr, "PT_DYNAMIC", apkenv_pid);
+            /* this segment contains the dynamic linking information */
+            si->dynamic = (unsigned *)(base + phdr->p_vaddr);
+        } else if (phdr->p_type == PT_GNU_RELRO) {
+            if ((phdr->p_vaddr >= si->size)
+                    || ((phdr->p_vaddr + phdr->p_memsz) > si->size)
+                    || ((base + phdr->p_vaddr + phdr->p_memsz) < base)) {
+                DL_ERR("%d invalid GNU_RELRO in '%s' "
+                       "p_vaddr=0x%08x p_memsz=0x%08x", apkenv_pid, si->name,
+                       phdr->p_vaddr, phdr->p_memsz);
+                goto fail;
+            }
+            si->gnu_relro_start = (Elf32_Addr) (base + phdr->p_vaddr);
+            si->gnu_relro_len = (unsigned) phdr->p_memsz;
+        } else {
+#ifdef ANDROID_ARM_LINKER
+            if (phdr->p_type == PT_ARM_EXIDX) {
+                DEBUG_DUMP_PHDR(phdr, "PT_ARM_EXIDX", apkenv_pid);
+                /* exidx entries (used for stack unwinding) are 8 bytes each.
+                 */
+                si->ARM_exidx = (unsigned *)phdr->p_vaddr;
+                si->ARM_exidx_count = phdr->p_memsz / 8;
+            }
+#endif
+        }
+
+    }
+
+    /* Sanity check */
+    if (total_sz > si->size) {
+        DL_ERR("%5d - Total length (0x%08x) of mapped segments from '%s' is "
+              "greater than what was allocated (0x%08x). THIS IS BAD!",
+              apkenv_pid, total_sz, si->name, si->size);
+        goto fail;
+    }
+
+    TRACE("[ %5d - Finish loading segments for '%s' @ 0x%08x. "
+          "Total memory footprint: 0x%08x bytes ]\n", apkenv_pid, si->name,
+          (unsigned)si->base, si->size);
+    return 0;
+
+fail:
+    /* We can just blindly unmap the entire region even though some things
+     * were mapped in originally with anonymous and others could have been
+     * been mapped in from the file before we failed. The kernel will unmap
+     * all the pages in the range, irrespective of how they got there.
+     */
+    munmap((void *)si->base, si->size);
+    si->flags |= FLAG_ERROR;
+    return -1;
+}
+
+/* TODO: Implement this to take care of the fact that Android ARM
+ * ELF objects shove everything into a single loadable segment that has the
+ * write bit set. wr_offset is then used to set non-(data|bss) pages to be
+ * non-writable.
+ */
+#if 0
+static unsigned
+get_wr_offset(int fd, const char *name, Elf32_Ehdr *ehdr)
+{
+    Elf32_Shdr *shdr_start;
+    Elf32_Shdr *shdr;
+    int shdr_sz = ehdr->e_shnum * sizeof(Elf32_Shdr);
+    int cnt;
+    unsigned wr_offset = 0xffffffff;
+
+    shdr_start = mmap(0, shdr_sz, PROT_READ, MAP_PRIVATE, fd,
+                      ehdr->e_shoff & (~PAGE_MASK));
+    if (shdr_start == MAP_FAILED) {
+        WARN("%5d - Could not read section header info from '%s'. Will not "
+             "not be able to determine write-protect offset.\n", apkenv_pid, name);
+        return (unsigned)-1;
+    }
+
+    for(cnt = 0, shdr = shdr_start; cnt < ehdr->e_shnum; ++cnt, ++shdr) {
+        if ((shdr->sh_type != SHT_NULL) && (shdr->sh_flags & SHF_WRITE) &&
+            (shdr->sh_addr < wr_offset)) {
+            wr_offset = shdr->sh_addr;
+        }
+    }
+
+    munmap(shdr_start, shdr_sz);
+    return wr_offset;
+}
+#endif
+
+static soinfo *
+apkenv_load_library(const char *name)
+{
+    char fullpath[512];
+    int fd = apkenv_open_library(name, fullpath);
+    int cnt;
+    unsigned ext_sz;
+    unsigned req_base;
+    const char *bname;
+    soinfo *si = NULL;
+    Elf32_Ehdr *hdr;
+
+    if(fd == -1) {
+#if !LINKER_DEBUG
+        if (!is_lib_optional(name))
+#endif
+            DL_ERR("Library '%s' not found", name);
+        return NULL;
+    }
+
+    off_t end;
+    if ((end = lseek(fd, 0, SEEK_END)) < 0) {
+        DL_ERR("lseek() failed!");
+        goto fail;
+    }
+
+    uint8_t *bytes;
+    if (!(bytes = calloc(1, end))) {
+        DL_ERR("calloc() failed!");
+        goto fail;
+    }
+
+    /* We have to read the ELF header to figure out what to do with this image
+     */
+    if (lseek(fd, 0, SEEK_SET) < 0) {
+        DL_ERR("lseek() failed!");
+        goto fail;
+    }
+
+
+    if ((cnt = read(fd, bytes, end)) < 0) {
+        DL_ERR("read() failed!");
+        goto fail;
+    }
+
+    /* Parse the ELF header and get the size of the memory footprint for
+     * the library */
+    req_base = apkenv_get_lib_extents(fd, name, bytes, &ext_sz);
+    if (req_base == (unsigned)-1)
+        goto fail;
+    TRACE("[ %5d - '%s' (%s) wants base=0x%08x sz=0x%08x ]\n", apkenv_pid, name,
+          (req_base ? "prelinked" : "not pre-linked"), req_base, ext_sz);
+
+    /* Now configure the soinfo struct where we'll store all of our data
+     * for the ELF object. If the loading fails, we waste the entry, but
+     * same thing would happen if we failed during linking. Configuring the
+     * soinfo struct here is a lot more convenient.
+     */
+    bname = strrchr(name, '/');
+    si = apkenv_alloc_info(bname ? bname + 1 : name);
+    if (si == NULL)
+        goto fail;
+
+    /* apkenv */
+    strncpy(si->fullpath, fullpath, sizeof(si->fullpath));
+    si->fullpath[sizeof(si->fullpath) - 1] = 0;
+
+    /* Carve out a chunk of memory where we will map in the individual
+     * segments */
+    si->base = req_base;
+    si->size = ext_sz;
+    si->flags = 0;
+    si->entry = 0;
+    si->dynamic = (unsigned *)-1;
+    if (apkenv_alloc_mem_region(si) < 0)
+        goto fail;
+
+    TRACE("[ %5d allocated memory for %s @ %p (0x%08x) ]\n",
+          apkenv_pid, name, (void *)si->base, (unsigned) ext_sz);
+
+    /* Now actually load the library's segments into right places in memory */
+    if (apkenv_load_segments(fd, bytes, si) < 0) {
+        goto fail;
+    }
+
+    /* this might not be right. Technically, we don't even need this info
+     * once we go through 'apkenv_load_segments'. */
+    hdr = (Elf32_Ehdr *)si->base;
+    si->phdr = (Elf32_Phdr *)((unsigned char *)si->base + hdr->e_phoff);
+    si->phnum = hdr->e_phnum;
+    /**/
+
+    close(fd);
+    return si;
+
+fail:
+    if (si) apkenv_free_info(si);
+    close(fd);
+    return NULL;
+}
+
+static soinfo *
+apkenv_init_library(soinfo *si)
+{
+    unsigned wr_offset = 0xffffffff;
+
+    /* At this point we know that whatever is loaded @ base is a valid ELF
+     * shared library whose segments are properly mapped in. */
+    TRACE("[ %5d apkenv_init_library base=0x%08x sz=0x%08x name='%s') ]\n",
+          apkenv_pid, si->base, si->size, si->name);
+    if(apkenv_link_image(si, wr_offset)) {
+            /* We failed to link.  However, we can only restore libbase
+            ** if no additional libraries have moved it since we updated it.
+            */
+        munmap((void *)si->base, si->size);
+        return NULL;
+    }
+
+    return si;
+}
+
+soinfo *apkenv_find_library(const char *name)
+{
+    soinfo *si;
+    const char *bname;
+
+#if ALLOW_SYMBOLS_FROM_MAIN
+    if (name == NULL)
+        return apkenv_somain;
+#else
+    if (name == NULL)
+        return NULL;
+#endif
+
+    bname = strrchr(name, '/');
+    bname = bname ? bname + 1 : name;
+
+    for(si = apkenv_solist; si != 0; si = si->next){
+        if(!strcmp(bname, si->name)) {
+            if(si->flags & FLAG_ERROR) {
+                DL_ERR("%5d '%s' failed to load previously", apkenv_pid, bname);
+                return NULL;
+            }
+            if(si->flags & FLAG_LINKED) return si;
+            DL_ERR("OOPS: %5d recursive link to '%s'", apkenv_pid, si->name);
+            return NULL;
+        }
+    }
+
+    TRACE("[ %5d '%s' has not been loaded yet.  Locating...]\n", apkenv_pid, name);
+    si = apkenv_load_library(name);
+    if(si == NULL)
+        return NULL;
+    return apkenv_init_library(si);
+}
+
+/* TODO:
+ *   notify gdb of unload
+ *   for non-prelinked libraries, find a way to decrement libbase
+ */
+static void apkenv_call_destructors(soinfo *si);
+unsigned apkenv_unload_library(soinfo *si)
+{
+    unsigned *d;
+    if (si->refcount == 1) {
+        TRACE("%5d unloading '%s'\n", apkenv_pid, si->name);
+        apkenv_call_destructors(si);
+
+        /*
+         * Make sure that we undo the PT_GNU_RELRO protections we added
+         * in apkenv_link_image. This is needed to undo the DT_NEEDED hack below.
+         */
+        if ((si->gnu_relro_start != 0) && (si->gnu_relro_len != 0)) {
+            Elf32_Addr start = (si->gnu_relro_start & ~PAGE_MASK);
+            unsigned len = (si->gnu_relro_start - start) + si->gnu_relro_len;
+            if (mprotect((void *) start, len, PROT_READ | PROT_WRITE) < 0)
+                DL_ERR("%5d %s: could not undo GNU_RELRO protections. "
+                       "Expect a crash soon. errno=%d (%s)",
+                       apkenv_pid, si->name, errno, strerror(errno));
+
+        }
+
+        for(d = si->dynamic; *d; d += 2) {
+            if(d[0] == DT_NEEDED){
+                soinfo *lsi = (soinfo *)d[1];
+
+                // The next line will segfault if the we don't undo the
+                // PT_GNU_RELRO protections (see comments above and in
+                // apkenv_link_image().
+                d[1] = 0;
+
+                if (apkenv_validate_soinfo(lsi)) {
+                    TRACE("%5d %s needs to unload %s\n", apkenv_pid,
+                          si->name, lsi->name);
+                    apkenv_unload_library(lsi);
+                }
+                else
+                    DL_ERR("%5d %s: could not unload dependent library",
+                           apkenv_pid, si->name);
+            }
+        }
+
+        munmap((char *)si->base, si->size);
+        apkenv_notify_gdb_of_unload(si);
+        apkenv_free_info(si);
+        si->refcount = 0;
+    }
+    else {
+        si->refcount--;
+        PRINT("%5d not unloading '%s', decrementing refcount to %d\n",
+              apkenv_pid, si->name, si->refcount);
+    }
+    return si->refcount;
+}
+
+#define MIN(a,b) (((a)<(b))?(a):(b))
+
+/* TODO: don't use unsigned for addrs below. It works, but is not
+ * ideal. They should probably be either uint32_t, Elf32_Addr, or unsigned
+ * long.
+ */
+static int apkenv_reloc_library(soinfo *si, Elf32_Rel *rel, unsigned count)
+{
+    Elf32_Sym *symtab = si->symtab;
+    const char *strtab = si->strtab;
+    Elf32_Sym *s;
+    unsigned base;
+    Elf32_Rel *start = rel;
+    unsigned idx;
+
+    for (idx = 0; idx < count; ++idx) {
+        unsigned type = ELF32_R_TYPE(rel->r_info);
+        unsigned sym = ELF32_R_SYM(rel->r_info);
+        unsigned reloc = (unsigned)(rel->r_offset + si->base);
+        unsigned sym_addr = 0;
+        char *sym_name = NULL;
+        char wrap_sym_name[1024] = { 'b', 'i', 'o', 'n', 'i', 'c', '_' };
+
+        DEBUG("%5d Processing '%s' relocation at index %d\n", apkenv_pid,
+              si->name, idx);
+        if(sym != 0) {
+            sym_name = (char *)(strtab + symtab[sym].st_name);
+            memcpy(wrap_sym_name + 7, sym_name, MIN(sizeof(wrap_sym_name) - 7, strlen(sym_name)));
+            sym_addr = 0;
+            if ((sym_addr = dlsym(RTLD_DEFAULT, wrap_sym_name))) {
+               LINKER_DEBUG_PRINTF("%s hooked symbol %s to %x\n", si->name, wrap_sym_name, sym_addr);
+            } else if ((sym_addr = dlsym(RTLD_DEFAULT, sym_name))) {
+               LINKER_DEBUG_PRINTF("%s hooked symbol %s to %x\n", si->name, sym_name, sym_addr);
+            }
+#if 0
+            if ((sym_addr = (unsigned)apkenv_get_hooked_symbol(sym_name, 1)) != 0) {
+               LINKER_DEBUG_PRINTF("%s hooked symbol %s to %x\n", si->name, sym_name, sym_addr);
+            }
+#endif
+            else
+            {
+               s = apkenv__do_lookup(si, sym_name, &base);
+            }
+            if(sym_addr != 0)
+            {
+                sym_addr = (unsigned)create_wrapper(sym_name, (void*)sym_addr, WRAPPER_UNHOOKED);
+            } else
+            if(s == NULL) {
+                /* We only allow an undefined symbol if this is a weak
+                   reference..   */
+                s = &symtab[sym];
+                if (ELF32_ST_BIND(s->st_info) != STB_WEAK) {
+                    DL_ERR("%5d cannot locate '%s'...\n", apkenv_pid, sym_name);
+                    return -1;
+                }
+
+                /* IHI0044C AAELF 4.5.1.1:
+
+                   Libraries are not searched to resolve weak references.
+                   It is not an error for a weak reference to remain
+                   unsatisfied.
+
+                   During linking, the value of an undefined weak reference is:
+                   - Zero if the relocation type is absolute
+                   - The address of the place if the relocation is pc-relative
+                   - The address of nominial base address if the relocation
+                     type is base-relative.
+                  */
+
+                switch (type) {
+#if defined(ANDROID_ARM_LINKER)
+                case R_ARM_JUMP_SLOT:
+                case R_ARM_GLOB_DAT:
+                case R_ARM_ABS32:
+                case R_ARM_RELATIVE:    /* Don't care. */
+                case R_ARM_NONE:        /* Don't care. */
+#elif defined(ANDROID_X86_LINKER)
+                case R_386_JUMP_SLOT:
+                case R_386_GLOB_DAT:
+                case R_386_32:
+                case R_386_RELATIVE:    /* Dont' care. */
+#endif /* ANDROID_*_LINKER */
+                    /* sym_addr was initialized to be zero above or relocation
+                       code below does not care about value of sym_addr.
+                       No need to do anything.  */
+                    break;
+
+#if defined(ANDROID_X86_LINKER)
+                case R_386_PC32:
+                    sym_addr = reloc;
+                    break;
+#endif /* ANDROID_X86_LINKER */
+
+#if defined(ANDROID_ARM_LINKER)
+                case R_ARM_COPY:
+                    /* Fall through.  Can't really copy if weak symbol is
+                       not found in run-time.  */
+#endif /* ANDROID_ARM_LINKER */
+                default:
+                    DL_ERR("%5d unknown weak reloc type %d @ %p (%d)\n",
+                                 apkenv_pid, type, rel, (int) (rel - start));
+                    return -1;
+                }
+            } else {
+                /* We got a definition.  */
+#if 0
+            if((base == 0) && (si->base != 0)){
+                    /* linking from libraries to main image is bad */
+                DL_ERR("%5d cannot locate '%s'...",
+                       apkenv_pid, strtab + symtab[sym].st_name);
+                return -1;
+            }
+#endif
+                sym_addr = (unsigned)(s->st_value + base);
+                LINKER_DEBUG_PRINTF("%s symbol (from %s) %s to %x\n", si->name, apkenv_last_library_used, sym_name, sym_addr);
+                if(ELF32_ST_TYPE(s->st_info) == STT_FUNC) {
+                    sym_addr = (unsigned)create_wrapper(sym_name, (void*)sym_addr, WRAPPER_UNHOOKED);
+                }
+
+    }
+            COUNT_RELOC(RELOC_SYMBOL);
+        } else {
+            s = NULL;
+        }
+
+/* TODO: This is ugly. Split up the relocations by arch into
+ * different files.
+ */
+        switch(type){
+#if defined(ANDROID_ARM_LINKER)
+        case R_ARM_JUMP_SLOT:
+            COUNT_RELOC(RELOC_ABSOLUTE);
+            MARK(rel->r_offset);
+            TRACE_TYPE(RELO, "%5d RELO JMP_SLOT %08x <- %08x %s\n", apkenv_pid,
+                       reloc, sym_addr, sym_name);
+            *((unsigned*)reloc) = sym_addr;
+            break;
+        case R_ARM_GLOB_DAT:
+            COUNT_RELOC(RELOC_ABSOLUTE);
+            MARK(rel->r_offset);
+            TRACE_TYPE(RELO, "%5d RELO GLOB_DAT %08x <- %08x %s\n", apkenv_pid,
+                       reloc, sym_addr, sym_name);
+            *((unsigned*)reloc) = sym_addr;
+            break;
+        case R_ARM_ABS32:
+            COUNT_RELOC(RELOC_ABSOLUTE);
+            MARK(rel->r_offset);
+            TRACE_TYPE(RELO, "%5d RELO ABS %08x <- %08x %s\n", apkenv_pid,
+                       reloc, sym_addr, sym_name);
+            *((unsigned*)reloc) += sym_addr;
+            break;
+        case R_ARM_REL32:
+            COUNT_RELOC(RELOC_RELATIVE);
+            MARK(rel->r_offset);
+            TRACE_TYPE(RELO, "%5d RELO REL32 %08x <- %08x - %08x %s\n", apkenv_pid,
+                       reloc, sym_addr, rel->r_offset, sym_name);
+            *((unsigned*)reloc) += sym_addr - rel->r_offset;
+            break;
+#elif defined(ANDROID_X86_LINKER)
+        case R_386_JUMP_SLOT:
+            COUNT_RELOC(RELOC_ABSOLUTE);
+            MARK(rel->r_offset);
+            TRACE_TYPE(RELO, "%5d RELO JMP_SLOT %08x <- %08x %s\n", apkenv_pid,
+                       reloc, sym_addr, sym_name);
+            *((unsigned*)reloc) = sym_addr;
+            break;
+        case R_386_GLOB_DAT:
+            COUNT_RELOC(RELOC_ABSOLUTE);
+            MARK(rel->r_offset);
+            TRACE_TYPE(RELO, "%5d RELO GLOB_DAT %08x <- %08x %s\n", apkenv_pid,
+                       reloc, sym_addr, sym_name);
+            *((unsigned*)reloc) = sym_addr;
+            break;
+#endif /* ANDROID_*_LINKER */
+
+#if defined(ANDROID_ARM_LINKER)
+        case R_ARM_RELATIVE:
+#elif defined(ANDROID_X86_LINKER)
+        case R_386_RELATIVE:
+#endif /* ANDROID_*_LINKER */
+            COUNT_RELOC(RELOC_RELATIVE);
+            MARK(rel->r_offset);
+            if(sym){
+                DL_ERR("%5d odd RELATIVE form...", apkenv_pid);
+                return -1;
+            }
+            TRACE_TYPE(RELO, "%5d RELO RELATIVE %08x <- +%08x\n", apkenv_pid,
+                       reloc, si->base);
+            *((unsigned*)reloc) += si->base;
+            break;
+
+#if defined(ANDROID_X86_LINKER)
+        case R_386_32:
+            COUNT_RELOC(RELOC_RELATIVE);
+            MARK(rel->r_offset);
+
+            TRACE_TYPE(RELO, "%5d RELO R_386_32 %08x <- +%08x %s\n", apkenv_pid,
+                       reloc, sym_addr, sym_name);
+            *((unsigned *)reloc) += (unsigned)sym_addr;
+            break;
+
+        case R_386_PC32:
+            COUNT_RELOC(RELOC_RELATIVE);
+            MARK(rel->r_offset);
+            TRACE_TYPE(RELO, "%5d RELO R_386_PC32 %08x <- "
+                       "+%08x (%08x - %08x) %s\n", apkenv_pid, reloc,
+                       (sym_addr - reloc), sym_addr, reloc, sym_name);
+            *((unsigned *)reloc) += (unsigned)(sym_addr - reloc);
+            break;
+#endif /* ANDROID_X86_LINKER */
+
+#ifdef ANDROID_ARM_LINKER
+        case R_ARM_COPY:
+            COUNT_RELOC(RELOC_COPY);
+            MARK(rel->r_offset);
+            TRACE_TYPE(RELO, "%5d RELO %08x <- %d @ %08x %s\n", apkenv_pid,
+                       reloc, s->st_size, sym_addr, sym_name);
+            memcpy((void*)reloc, (void*)sym_addr, s->st_size);
+            break;
+        case R_ARM_NONE:
+            break;
+#endif /* ANDROID_ARM_LINKER */
+
+        default:
+            DL_ERR("%5d unknown reloc type %d @ %p (%d)",
+                  apkenv_pid, type, rel, (int) (rel - start));
+            return -1;
+        }
+        rel++;
+    }
+    return 0;
+}
+
+/* Please read the "Initialization and Termination functions" functions.
+ * of the linker design note in bionic/linker/README.TXT to understand
+ * what the following code is doing.
+ *
+ * The important things to remember are:
+ *
+ *   DT_PREINIT_ARRAY must be called first for executables, and should
+ *   not appear in shared libraries.
+ *
+ *   DT_INIT should be called before DT_INIT_ARRAY if both are present
+ *
+ *   DT_FINI should be called after DT_FINI_ARRAY if both are present
+ *
+ *   DT_FINI_ARRAY must be parsed in reverse order.
+ */
+
+static void apkenv_call_array(unsigned *ctor, int count, int reverse)
+{
+    int n, inc = 1;
+
+    if (reverse) {
+        ctor += (count-1);
+        inc   = -1;
+    }
+
+    for(n = count; n > 0; n--) {
+        TRACE("[ %5d Looking at %s *0x%08x == 0x%08x ]\n", apkenv_pid,
+              reverse ? "dtor" : "ctor",
+              (unsigned)ctor, (unsigned)*ctor);
+        void (*func)() = (void (*)()) *ctor;
+        ctor += inc;
+        if(((int) func == 0) || ((int) func == -1)) continue;
+        TRACE("[ %5d Calling func @ 0x%08x ]\n", apkenv_pid, (unsigned)func);
+        func();
+    }
+}
+
+void apkenv_call_constructors_recursive(soinfo *si)
+{
+    if (si->constructors_called)
+        return;
+    if (strcmp(si->name, "libc.so") == 0)
+return;
+    // Set this before actually calling the constructors, otherwise it doesn't
+    // protect against recursive constructor calls. One simple example of
+    // constructor recursion is the libc debug malloc, which is implemented in
+    // libc_malloc_debug_leak.so:
+    // 1. The program depends on libc, so libc's constructor is called here.
+    // 2. The libc constructor calls dlopen() to load libc_malloc_debug_leak.so.
+    // 3. dlopen() calls apkenv_call_constructors_recursive() with the newly created
+    //    soinfo for libc_malloc_debug_leak.so.
+    // 4. The debug so depends on libc, so apkenv_call_constructors_recursive() is
+    //    called again with the libc soinfo. If it doesn't trigger the early-
+    //    out above, the libc constructor will be called again (recursively!).
+    si->constructors_called = 1;
+
+    if (si->flags & FLAG_EXE) {
+        TRACE("[ %5d Calling preinit_array @ 0x%08x [%d] for '%s' ]\n",
+              apkenv_pid, (unsigned)si->preinit_array, si->preinit_array_count,
+              si->name);
+        apkenv_call_array(si->preinit_array, si->preinit_array_count, 0);
+        TRACE("[ %5d Done calling preinit_array for '%s' ]\n", apkenv_pid, si->name);
+    } else {
+        if (si->preinit_array) {
+            DL_ERR("%5d Shared library '%s' has a preinit_array table @ 0x%08x."
+                   " This is INVALID.", apkenv_pid, si->name,
+                   (unsigned)si->preinit_array);
+        }
+    }
+
+    if (si->dynamic) {
+        unsigned *d;
+        for(d = si->dynamic; *d; d += 2) {
+            if(d[0] == DT_NEEDED){
+                soinfo* lsi = (soinfo *)d[1];
+                if (!apkenv_validate_soinfo(lsi)) {
+                    DL_ERR("%5d bad DT_NEEDED pointer in %s",
+                           apkenv_pid, si->name);
+                } else {
+                    apkenv_call_constructors_recursive(lsi);
+                }
+            }
+        }
+    }
+
+    if (si->init_func) {
+        TRACE("[ %5d Calling init_func @ 0x%08x for '%s' ]\n", apkenv_pid,
+              (unsigned)si->init_func, si->name);
+        si->init_func();
+        TRACE("[ %5d Done calling init_func for '%s' ]\n", apkenv_pid, si->name);
+    }
+
+    if (si->init_array) {
+        TRACE("[ %5d Calling init_array @ 0x%08x [%d] for '%s' ]\n", apkenv_pid,
+              (unsigned)si->init_array, si->init_array_count, si->name);
+        apkenv_call_array(si->init_array, si->init_array_count, 0);
+        TRACE("[ %5d Done calling init_array for '%s' ]\n", apkenv_pid, si->name);
+    }
+
+}
+
+static void apkenv_call_destructors(soinfo *si)
+{
+    if (si->fini_array) {
+        TRACE("[ %5d Calling fini_array @ 0x%08x [%d] for '%s' ]\n", apkenv_pid,
+              (unsigned)si->fini_array, si->fini_array_count, si->name);
+        apkenv_call_array(si->fini_array, si->fini_array_count, 1);
+        TRACE("[ %5d Done calling fini_array for '%s' ]\n", apkenv_pid, si->name);
+    }
+
+    if (si->fini_func) {
+        TRACE("[ %5d Calling fini_func @ 0x%08x for '%s' ]\n", apkenv_pid,
+              (unsigned)si->fini_func, si->name);
+        si->fini_func();
+        TRACE("[ %5d Done calling fini_func for '%s' ]\n", apkenv_pid, si->name);
+    }
+}
+
+/* Force any of the closed stdin, stdout and stderr to be associated with
+   /dev/null. */
+static int apkenv_nullify_closed_stdio (void)
+{
+    int dev_null, i, status;
+    int return_value = 0;
+
+    dev_null = open("/dev/null", O_RDWR);
+    if (dev_null < 0) {
+        DL_ERR("Cannot open /dev/null.");
+        return -1;
+    }
+    TRACE("[ %5d Opened /dev/null file-descriptor=%d]\n", apkenv_pid, dev_null);
+
+    /* If any of the stdio file descriptors is valid and not associated
+       with /dev/null, dup /dev/null to it.  */
+    for (i = 0; i < 3; i++) {
+        /* If it is /dev/null already, we are done. */
+        if (i == dev_null)
+            continue;
+
+        TRACE("[ %5d Nullifying stdio file descriptor %d]\n", apkenv_pid, i);
+        /* The man page of fcntl does not say that fcntl(..,F_GETFL)
+           can be interrupted but we do this just to be safe. */
+        do {
+          status = fcntl(i, F_GETFL);
+        } while (status < 0 && errno == EINTR);
+
+        /* If file is openned, we are good. */
+        if (status >= 0)
+          continue;
+
+        /* The only error we allow is that the file descriptor does not
+           exist, in which case we dup /dev/null to it. */
+        if (errno != EBADF) {
+            DL_ERR("nullify_stdio: unhandled error %s", strerror(errno));
+            return_value = -1;
+            continue;
+        }
+
+        /* Try dupping /dev/null to this stdio file descriptor and
+           repeat if there is a signal.  Note that any errors in closing
+           the stdio descriptor are lost.  */
+        do {
+            status = dup2(dev_null, i);
+        } while (status < 0 && errno == EINTR);
+
+        if (status < 0) {
+            DL_ERR("nullify_stdio: dup2 error %s", strerror(errno));
+            return_value = -1;
+            continue;
+        }
+    }
+
+    /* If /dev/null is not one of the stdio file descriptors, close it. */
+    if (dev_null > 2) {
+        TRACE("[ %5d Closing /dev/null file-descriptor=%d]\n", apkenv_pid, dev_null);
+        do {
+            status = close(dev_null);
+        } while (status < 0 && errno == EINTR);
+
+        if (status < 0) {
+            DL_ERR("nullify_stdio: close error %s", strerror(errno));
+            return_value = -1;
+        }
+    }
+
+    return return_value;
+}
+
+static void apkenv_wrap_function(void *sym_addr, char *sym_name, int is_thumb, soinfo *si)
+{
+    void *hook = NULL;
+#ifdef APKENV_LATEHOOKS
+    if((hook = apkenv_get_hooked_symbol(sym_name, 0)) != NULL)
+    {
+        // if we have a hook redirect the call to that by overwriting
+        // the first 2 instruction of the function
+        // this should work in any case unless the hook is wrong
+        // or the function shorter than 64-bit (2 32-Bit instructions)
+        if(!is_thumb)
+        {
+            DEBUG("HOOKING INTERNAL (ARM) FUNCTION %s@%x (in %s) TO: %x\n",sym_name,sym_addr,si->name,hook);
+            ((int32_t*)sym_addr)[0] = 0xe51ff004; // ldr pc, [pc, -#4] (load the hooks address into pc)
+            ((int32_t*)sym_addr)[1] = (uint32_t)create_wrapper(sym_name, hook, WRAPPER_LATEHOOK);
+
+            __clear_cache((int32_t*)sym_addr, (int32_t*)sym_addr + 2);
+        }
+        else
+        {
+            DEBUG("HOOKING INTERNAL (THUMB) FUNCTION %s@%x (in %s) TO: %x\n",sym_name,sym_addr,si->name,hook);
+            sym_addr = (void*)((char*)sym_addr - 1); // get actual sym_addr
+
+            ((int16_t*)sym_addr)[0] = 0xB401; /* push {r0} */
+            ((int16_t*)sym_addr)[1] = 0xF8DF; /* ldr r0, [pc, #8] */
+            ((int16_t*)sym_addr)[2] = 0x0008; /* continuation of last instruction */
+            ((int16_t*)sym_addr)[3] = 0x4684; /* mov ip, r0 */
+            ((int16_t*)sym_addr)[4] = 0xBC01; /* pop {r0} */
+            ((int16_t*)sym_addr)[5] = 0x4760; /* bx ip */
+
+            void *wrp = create_wrapper(sym_name, hook, WRAPPER_LATEHOOK);
+
+            // store the hooks address
+            ((int16_t*)sym_addr)[6] = (uint32_t)wrp & 0x0000FFFF;
+            ((int16_t*)sym_addr)[7] = (uint32_t)wrp >> 16;
+
+            __clear_cache((int16_t*)sym_addr, (int16_t*)sym_addr + 8);
+        }
+    }
+    else
+#endif /* APKENV_LATEHOOKS */
+    // TODO: this will fail if the first 2 instructions do something pc related
+    // (this DOES NOT happen very often)
+    if(sym_addr && !is_thumb)
+    {
+        DEBUG("CREATING ARM WRAPPER FOR: %s@%x (in %s)\n", sym_name, (unsigned)sym_addr, si->name);
+
+        create_wrapper(sym_name, sym_addr, WRAPPER_ARM_INJECTION);
+    }
+    // TODO: this will fail if the first 2-5 instructions do something pc related
+    // (this DOES happen very often)
+    else if(sym_addr && is_thumb)
+    {
+        DEBUG("CREATING THUMB WRAPPER FOR: %s@%x (in %s)\n",sym_name, (unsigned)sym_addr,si->name);
+
+        create_wrapper(sym_name, sym_addr, WRAPPER_THUMB_INJECTION);
+    }
+}
+
+
+/* Franz-Josef Haider apkenv_create_latehook_wrappers */
+static void apkenv_create_latehook_wrappers(soinfo *si)
+{
+    Elf32_Sym *s;
+
+    unsigned int n = 0;
+    for(n=0;n<si->nchain;n++)
+    {
+        s = si->symtab + n;
+        switch(ELF32_ST_BIND(s->st_info))
+        {
+            case STB_GLOBAL:
+            case STB_WEAK:
+                if(s->st_shndx == 0) continue;
+
+                if(ELF32_ST_TYPE(s->st_info) == STT_FUNC) // only wrap functions
+                {
+                    char *sym_name = (char*)(si->strtab + s->st_name);
+                    void *sym_addr = (void*)(intptr_t)(si->base + s->st_value);
+
+                    int is_thumb = ((int32_t)(intptr_t)sym_addr) & 0x00000001;
+
+                    apkenv_wrap_function(sym_addr,sym_name,is_thumb,si);
+               }
+        }
+    }
+}
+
+
+static int apkenv_link_image(soinfo *si, unsigned wr_offset)
+{
+    unsigned *d;
+    Elf32_Phdr *phdr = si->phdr;
+    int phnum = si->phnum;
+
+    INFO("[ %5d linking %s ]\n", apkenv_pid, si->name);
+    DEBUG("%5d si->base = 0x%08x si->flags = 0x%08x\n", apkenv_pid,
+          si->base, si->flags);
+
+    if (si->flags & (FLAG_EXE | FLAG_LINKER)) {
+        /* Locate the needed program segments (DYNAMIC/ARM_EXIDX) for
+         * linkage info if this is the executable or the linker itself.
+         * If this was a dynamic lib, that would have been done at load time.
+         *
+         * TODO: It's unfortunate that small pieces of this are
+         * repeated from the apkenv_load_library routine. Refactor this just
+         * slightly to reuse these bits.
+         */
+        si->size = 0;
+        for(; phnum > 0; --phnum, ++phdr) {
+#ifdef ANDROID_ARM_LINKER
+            if(phdr->p_type == PT_ARM_EXIDX) {
+                /* exidx entries (used for stack unwinding) are 8 bytes each.
+                 */
+                si->ARM_exidx = (unsigned *)phdr->p_vaddr;
+                si->ARM_exidx_count = phdr->p_memsz / 8;
+            }
+#endif
+            if (phdr->p_type == PT_LOAD) {
+                /* For the executable, we use the si->size field only in
+                   dl_unwind_find_exidx(), so the meaning of si->size
+                   is not the size of the executable; it is the distance
+                   between the load location of the executable and the last
+                   address of the loadable part of the executable.
+                   We use the range [si->base, si->base + si->size) to
+                   determine whether a PC value falls within the executable
+                   section. Of course, if a value is between si->base and
+                   (si->base + phdr->p_vaddr), it's not in the executable
+                   section, but a) we shouldn't be asking for such a value
+                   anyway, and b) if we have to provide an EXIDX for such a
+                   value, then the executable's EXIDX is probably the better
+                   choice.
+                */
+                DEBUG_DUMP_PHDR(phdr, "PT_LOAD", apkenv_pid);
+                if (phdr->p_vaddr + phdr->p_memsz > si->size)
+                    si->size = phdr->p_vaddr + phdr->p_memsz;
+                /* try to remember what range of addresses should be write
+                 * protected */
+                if (!(phdr->p_flags & PF_W)) {
+                    unsigned _end;
+
+                    if (si->base + phdr->p_vaddr < si->wrprotect_start)
+                        si->wrprotect_start = si->base + phdr->p_vaddr;
+                    _end = (((si->base + phdr->p_vaddr + phdr->p_memsz + PAGE_SIZE - 1) &
+                             (~PAGE_MASK)));
+                    if (_end > si->wrprotect_end)
+                        si->wrprotect_end = _end;
+                    /* Make the section writable just in case we'll have to
+                     * write to it during relocation (i.e. text segment).
+                     * However, we will remember what range of addresses
+                     * should be write protected.
+                     */
+                    mprotect((void *) (si->base + phdr->p_vaddr),
+                             phdr->p_memsz,
+                             PFLAGS_TO_PROT(phdr->p_flags) | PROT_WRITE);
+                }
+            } else if (phdr->p_type == PT_DYNAMIC) {
+                if (si->dynamic != (unsigned *)-1) {
+                    DL_ERR("%5d multiple PT_DYNAMIC segments found in '%s'. "
+                          "Segment at 0x%08x, previously one found at 0x%08x",
+                          apkenv_pid, si->name, si->base + phdr->p_vaddr,
+                          (unsigned)si->dynamic);
+                    goto fail;
+                }
+                DEBUG_DUMP_PHDR(phdr, "PT_DYNAMIC", apkenv_pid);
+                si->dynamic = (unsigned *) (si->base + phdr->p_vaddr);
+            } else if (phdr->p_type == PT_GNU_RELRO) {
+                if ((phdr->p_vaddr >= si->size)
+                        || ((phdr->p_vaddr + phdr->p_memsz) > si->size)
+                        || ((si->base + phdr->p_vaddr + phdr->p_memsz) < si->base)) {
+                    DL_ERR("%d invalid GNU_RELRO in '%s' "
+                           "p_vaddr=0x%08x p_memsz=0x%08x", apkenv_pid, si->name,
+                           phdr->p_vaddr, phdr->p_memsz);
+                    goto fail;
+                }
+                si->gnu_relro_start = (Elf32_Addr) (si->base + phdr->p_vaddr);
+                si->gnu_relro_len = (unsigned) phdr->p_memsz;
+            }
+        }
+    }
+
+    if (si->dynamic == (unsigned *)-1) {
+        DL_ERR("%5d missing PT_DYNAMIC?!", apkenv_pid);
+        goto fail;
+    }
+
+    DEBUG("%5d dynamic = %p\n", apkenv_pid, si->dynamic);
+
+    /* extract useful information from dynamic section */
+    for(d = si->dynamic; *d; d++){
+        DEBUG("%5d d = %p, d[0] = 0x%08x d[1] = 0x%08x\n", apkenv_pid, d, d[0], d[1]);
+        switch(*d++){
+        case DT_HASH:
+            si->nbucket = ((unsigned *) (si->base + *d))[0];
+            si->nchain = ((unsigned *) (si->base + *d))[1];
+            si->bucket = (unsigned *) (si->base + *d + 8);
+            si->chain = (unsigned *) (si->base + *d + 8 + si->nbucket * 4);
+            break;
+        case DT_STRTAB:
+            si->strtab = (const char *) (si->base + *d);
+            break;
+        case DT_SYMTAB:
+            si->symtab = (Elf32_Sym *) (si->base + *d);
+            break;
+        case DT_PLTREL:
+            if(*d != DT_REL) {
+                DL_ERR("DT_RELA not supported");
+                goto fail;
+            }
+            break;
+        case DT_JMPREL:
+            si->plt_rel = (Elf32_Rel*) (si->base + *d);
+            break;
+        case DT_PLTRELSZ:
+            si->plt_rel_count = *d / 8;
+            break;
+        case DT_REL:
+            si->rel = (Elf32_Rel*) (si->base + *d);
+            break;
+        case DT_RELSZ:
+            si->rel_count = *d / 8;
+            break;
+        case DT_PLTGOT:
+            /* Save this in case we decide to do lazy binding. We don't yet. */
+            si->plt_got = (unsigned *)(si->base + *d);
+            break;
+        case DT_DEBUG:
+            // Set the DT_DEBUG entry to the addres of _r_debug for GDB
+            *d = (int) &_r_debug;
+            break;
+         case DT_RELA:
+            DL_ERR("%5d DT_RELA not supported", apkenv_pid);
+            goto fail;
+        case DT_INIT:
+            si->init_func = (void (*)(void))(si->base + *d);
+            DEBUG("%5d %s constructors (init func) found at %p\n",
+                  apkenv_pid, si->name, si->init_func);
+            break;
+        case DT_FINI:
+            si->fini_func = (void (*)(void))(si->base + *d);
+            DEBUG("%5d %s destructors (fini func) found at %p\n",
+                  apkenv_pid, si->name, si->fini_func);
+            break;
+        case DT_INIT_ARRAY:
+            si->init_array = (unsigned *)(si->base + *d);
+            DEBUG("%5d %s constructors (init_array) found at %p\n",
+                  apkenv_pid, si->name, si->init_array);
+            break;
+        case DT_INIT_ARRAYSZ:
+            si->init_array_count = ((unsigned)*d) / sizeof(Elf32_Addr);
+            break;
+        case DT_FINI_ARRAY:
+            si->fini_array = (unsigned *)(si->base + *d);
+            DEBUG("%5d %s destructors (fini_array) found at %p\n",
+                  apkenv_pid, si->name, si->fini_array);
+            break;
+        case DT_FINI_ARRAYSZ:
+            si->fini_array_count = ((unsigned)*d) / sizeof(Elf32_Addr);
+            break;
+        case DT_PREINIT_ARRAY:
+            si->preinit_array = (unsigned *)(si->base + *d);
+            DEBUG("%5d %s constructors (preinit_array) found at %p\n",
+                  apkenv_pid, si->name, si->preinit_array);
+            break;
+        case DT_PREINIT_ARRAYSZ:
+            si->preinit_array_count = ((unsigned)*d) / sizeof(Elf32_Addr);
+            break;
+        case DT_TEXTREL:
+            /* TODO: make use of this. */
+            /* this means that we might have to write into where the text
+             * segment was loaded during relocation... Do something with
+             * it.
+             */
+            DEBUG("%5d Text segment should be writable during relocation.\n",
+                  apkenv_pid);
+            break;
+        }
+    }
+
+    DEBUG("%5d si->base = 0x%08x, si->strtab = %p, si->symtab = %p\n",
+           apkenv_pid, si->base, si->strtab, si->symtab);
+
+    if((si->strtab == 0) || (si->symtab == 0)) {
+        DL_ERR("%5d missing essential tables", apkenv_pid);
+        goto fail;
+    }
+
+    /* if this is the main executable, then load all of the apkenv_preloads now */
+    if(si->flags & FLAG_EXE) {
+        int i;
+        memset(apkenv_preloads, 0, sizeof(apkenv_preloads));
+        for(i = 0; apkenv_ldpreload_names[i] != NULL; i++) {
+            soinfo *lsi = apkenv_find_library(apkenv_ldpreload_names[i]);
+            if(lsi == 0) {
+                apkenv_strlcpy(apkenv_tmp_err_buf, apkenv_linker_get_error(), sizeof(apkenv_tmp_err_buf));
+                DL_ERR("%5d could not load needed library '%s' for '%s' (%s)",
+                       apkenv_pid, apkenv_ldpreload_names[i], si->name, apkenv_tmp_err_buf);
+                goto fail;
+            }
+            lsi->refcount++;
+            apkenv_preloads[i] = lsi;
+        }
+    }
+
+    for(d = si->dynamic; *d; d += 2) {
+        if(d[0] == DT_NEEDED){
+            DEBUG("%5d %s needs %s\n", apkenv_pid, si->name, si->strtab + d[1]);
+            soinfo *lsi = NULL;
+#if 1
+            // if (get_builtin_lib_handle(si->strtab + d[1]) == NULL)
+            lsi = apkenv_find_library(si->strtab + d[1]);
+            if (!lsi && dlopen(si->strtab + d[1], RTLD_NOW | RTLD_GLOBAL)) {
+                DEBUG("Loaded %s with glibc dlopen\n", si->strtab + d[1]);
+            }
+#endif
+            if(lsi == 0) {
+                /**
+                 * XXX Dirty Hack Alarm --thp XXX
+                 *
+                 * For libraries that are not found, simply use libdl's soinfo,
+                 * in order to not break downstream users of the library while
+                 * still allowing the application to start up.
+                 **/
+                lsi = &apkenv_libdl_info;
+                //apkenv_strlcpy(apkenv_tmp_err_buf, apkenv_linker_get_error(), sizeof(apkenv_tmp_err_buf));
+                //DL_ERR("%5d could not load needed library '%s' for '%s' (%s)",
+                //       apkenv_pid, si->strtab + d[1], si->name, apkenv_tmp_err_buf);
+                //continue;
+                //goto fail;
+            }
+            /* Save the soinfo of the loaded DT_NEEDED library in the payload
+               of the DT_NEEDED entry itself, so that we can retrieve the
+               soinfo directly later from the dynamic segment.  This is a hack,
+               but it allows us to map from DT_NEEDED to soinfo efficiently
+               later on when we resolve relocations, trying to look up a symbol
+               with dlsym().
+            */
+            d[1] = (intptr_t)lsi;
+            lsi->refcount++;
+        }
+    }
+
+    if(si->plt_rel) {
+        DEBUG("[ %5d relocating %s plt ]\n", apkenv_pid, si->name );
+        if(apkenv_reloc_library(si, si->plt_rel, si->plt_rel_count))
+            goto fail;
+    }
+    if(si->rel) {
+        DEBUG("[ %5d relocating %s ]\n", apkenv_pid, si->name );
+        if(apkenv_reloc_library(si, si->rel, si->rel_count))
+            goto fail;
+    }
+
+    apkenv_create_latehook_wrappers(si);
+
+    si->flags |= FLAG_LINKED;
+    DEBUG("[ %5d finished linking %s ]\n", apkenv_pid, si->name);
+
+#if 0
+    /* This is the way that the old dynamic linker did protection of
+     * non-writable areas. It would scan section headers and find where
+     * .text ended (rather where .data/.bss began) and assume that this is
+     * the upper range of the non-writable area. This is too coarse,
+     * and is kept here for reference until we fully move away from single
+     * segment elf objects. See the code in get_wr_offset (also #if'd 0)
+     * that made this possible.
+     */
+    if(wr_offset < 0xffffffff){
+        mprotect((void*) si->base, wr_offset, PROT_READ | PROT_EXEC);
+    }
+#else
+    /* TODO: Verify that this does the right thing in all cases, as it
+     * presently probably does not. It is possible that an ELF image will
+     * come with multiple read-only segments. What we ought to do is scan
+     * the program headers again and mprotect all the read-only segments.
+     * To prevent re-scanning the program header, we would have to build a
+     * list of loadable segments in si, and then scan that instead. */
+    if (si->wrprotect_start != 0xffffffff && si->wrprotect_end != 0) {
+        mprotect((void *)(intptr_t)si->wrprotect_start,
+                 si->wrprotect_end - si->wrprotect_start,
+                 PROT_READ | PROT_EXEC);
+    }
+#endif
+
+    if (si->gnu_relro_start != 0 && si->gnu_relro_len != 0) {
+        Elf32_Addr start = (si->gnu_relro_start & ~PAGE_MASK);
+        unsigned len = (si->gnu_relro_start - start) + si->gnu_relro_len;
+        if (mprotect((void *)(intptr_t)start, len, PROT_READ) < 0) {
+            DL_ERR("%5d GNU_RELRO mprotect of library '%s' failed: %d (%s)\n",
+                   apkenv_pid, si->name, errno, strerror(errno));
+            goto fail;
+        }
+    }
+
+    /* If this is a SET?ID program, dup /dev/null to opened stdin,
+       stdout and stderr to close a security hole described in:
+
+    ftp://ftp.freebsd.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-02:23.stdio.asc
+
+     */
+    if (apkenv_program_is_setuid)
+        apkenv_nullify_closed_stdio ();
+    apkenv_notify_gdb_of_load(si);
+    return 0;
+
+fail:
+    ERROR("failed to link %s\n", si->name);
+    si->flags |= FLAG_ERROR;
+    return -1;
+}
+
+void apkenv_parse_library_path(const char *path, char *delim)
+{
+    size_t len;
+    char *apkenv_ldpaths_bufp = apkenv_ldpaths_buf;
+    int i = 0;
+
+    len = apkenv_strlcpy(apkenv_ldpaths_buf, path, sizeof(apkenv_ldpaths_buf));
+
+    while (i < LDPATH_MAX && (apkenv_ldpaths[i] = strsep(&apkenv_ldpaths_bufp, delim))) {
+        if (*apkenv_ldpaths[i] != '\0')
+            ++i;
+    }
+
+    /* Forget the last path if we had to truncate; this occurs if the 2nd to
+     * last char isn't '\0' (i.e. not originally a delim). */
+    if (i > 0 && len >= sizeof(apkenv_ldpaths_buf) &&
+            apkenv_ldpaths_buf[sizeof(apkenv_ldpaths_buf) - 2] != '\0') {
+        apkenv_ldpaths[i - 1] = NULL;
+    } else {
+        apkenv_ldpaths[i] = NULL;
+    }
+}
+
+static void apkenv_parse_apkenv_preloads(const char *path, char *delim)
+{
+    size_t len;
+    char *apkenv_ldpreloads_bufp = apkenv_ldpreloads_buf;
+    int i = 0;
+
+    len = apkenv_strlcpy(apkenv_ldpreloads_buf, path, sizeof(apkenv_ldpreloads_buf));
+
+    while (i < LDPRELOAD_MAX && (apkenv_ldpreload_names[i] = strsep(&apkenv_ldpreloads_bufp, delim))) {
+        if (*apkenv_ldpreload_names[i] != '\0') {
+            ++i;
+        }
+    }
+
+    /* Forget the last path if we had to truncate; this occurs if the 2nd to
+     * last char isn't '\0' (i.e. not originally a delim). */
+    if (i > 0 && len >= sizeof(apkenv_ldpreloads_buf) &&
+            apkenv_ldpreloads_buf[sizeof(apkenv_ldpreloads_buf) - 2] != '\0') {
+        apkenv_ldpreload_names[i - 1] = NULL;
+    } else {
+        apkenv_ldpreload_names[i] = NULL;
+    }
+}
+
+/*
+ * This code is called after the linker has linked itself and
+ * fixed it's own GOT. It is safe to make references to externs
+ * and other non-local data at this point.
+ */
+static unsigned apkenv___linker_init_post_relocation(unsigned **elfdata)
+{
+    static soinfo linker_soinfo;
+
+    int argc = (int)(intptr_t)*elfdata;
+    char **argv = (char**) (elfdata + 1);
+    unsigned *vecs = (unsigned*) (argv + argc + 1);
+    unsigned *v;
+    soinfo *si;
+    struct link_map * map;
+    const char *ldpath_env = NULL;
+    const char *ldpreload_env = NULL;
+
+    /* NOTE: we store the elfdata pointer on a special location
+     *       of the temporary TLS area in order to pass it to
+     *       the C Library's runtime initializer.
+     *
+     *       The initializer must clear the slot and reset the TLS
+     *       to point to a different location to ensure that no other
+     *       shared library constructor can access it.
+     */
+#if 0
+    __libc_init_tls(elfdata);
+#endif
+
+    apkenv_pid = getpid();
+
+#if TIMING
+    struct timeval t0, t1;
+    gettimeofday(&t0, 0);
+#endif
+
+    /* Initialize environment functions, and get to the ELF aux vectors table */
+    vecs = apkenv_linker_env_init(vecs);
+
+    /* Check auxv for AT_SECURE first to see if program is setuid, setgid,
+       has file caps, or caused a SELinux/AppArmor domain transition. */
+    for (v = vecs; v[0]; v += 2) {
+        if (v[0] == AT_SECURE) {
+            /* kernel told us whether to enable secure mode */
+            apkenv_program_is_setuid = v[1];
+            goto sanitize;
+        }
+    }
+
+    /* Kernel did not provide AT_SECURE - fall back on legacy test. */
+    apkenv_program_is_setuid = (getuid() != geteuid()) || (getgid() != getegid());
+
+sanitize:
+    /* Sanitize environment if we're loading a setuid program */
+    if (apkenv_program_is_setuid)
+        apkenv_linker_env_secure();
+
+#if 0
+    apkenv_debugger_init();
+#endif
+
+    /* Get a few environment variables */
+    {
+#if LINKER_DEBUG
+        const char* env;
+        env = apkenv_linker_env_get("DEBUG"); /* XXX: TODO: Change to LD_DEBUG */
+        if (env)
+            apkenv_debug_verbosity = atoi(env);
+#endif
+
+        /* Normally, these are cleaned by linker_env_secure, but the test
+         * against apkenv_program_is_setuid doesn't cost us anything */
+        if (!apkenv_program_is_setuid) {
+            ldpath_env = getenv("LD_LIBRARY_PATH");
+            ldpreload_env = getenv("LD_PRELOAD");
+        }
+    }
+
+    INFO("[ android linker & debugger ]\n");
+    DEBUG("%5d elfdata @ 0x%08x\n", apkenv_pid, (unsigned)elfdata);
+
+    si = apkenv_alloc_info(argv[0]);
+    if(si == 0) {
+        exit(-1);
+    }
+
+        /* bootstrap the link map, the main exe always needs to be first */
+    si->flags |= FLAG_EXE;
+    map = &(si->linkmap);
+
+    map->l_addr = 0;
+    map->l_name = argv[0];
+    map->l_prev = NULL;
+    map->l_next = NULL;
+
+    _r_debug.r_map = map;
+    apkenv_r_debug_tail = map;
+
+        /* gdb expects the linker to be in the debug shared object list,
+         * and we need to make sure that the reported load address is zero.
+         * Without this, gdb gets the wrong idea of where rtld_db_dlactivity()
+         * is.  Don't use apkenv_alloc_info(), because the linker shouldn't
+         * be on the soinfo list.
+         */
+    apkenv_strlcpy((char*) linker_soinfo.name, "/system/bin/linker", sizeof linker_soinfo.name);
+    linker_soinfo.flags = 0;
+    linker_soinfo.base = 0;     // This is the important part; must be zero.
+    apkenv_insert_soinfo_into_debug_map(&linker_soinfo);
+
+        /* extract information passed from the kernel */
+    while(vecs[0] != 0){
+        switch(vecs[0]){
+        case AT_PHDR:
+            si->phdr = (Elf32_Phdr*)(intptr_t)vecs[1];
+            break;
+        case AT_PHNUM:
+            si->phnum = (int) vecs[1];
+            break;
+        case AT_ENTRY:
+            si->entry = vecs[1];
+            break;
+        }
+        vecs += 2;
+    }
+
+    /* Compute the value of si->base. We can't rely on the fact that
+     * the first entry is the PHDR because this will not be true
+     * for certain executables (e.g. some in the NDK unit test suite)
+     */
+    int nn;
+    si->base = 0;
+    for ( nn = 0; nn < si->phnum; nn++ ) {
+        if (si->phdr[nn].p_type == PT_PHDR) {
+            si->base = (Elf32_Addr)(intptr_t)si->phdr - si->phdr[nn].p_vaddr;
+            break;
+        }
+    }
+    si->dynamic = (unsigned *)-1;
+    si->wrprotect_start = 0xffffffff;
+    si->wrprotect_end = 0;
+    si->refcount = 1;
+    si->gnu_relro_start = 0;
+    si->gnu_relro_len = 0;
+
+        /* Use LD_LIBRARY_PATH if we aren't setuid/setgid */
+    if (ldpath_env)
+        apkenv_parse_library_path(ldpath_env, ":");
+
+    if (ldpreload_env) {
+        apkenv_parse_apkenv_preloads(ldpreload_env, " :");
+    }
+    if(apkenv_link_image(si, 0)) {
+        char errmsg[] = "CANNOT LINK EXECUTABLE\n";
+        write(2, apkenv___linker_dl_err_buf, strlen(apkenv___linker_dl_err_buf));
+        write(2, errmsg, sizeof(errmsg));
+        exit(-1);
+    }
+
+    apkenv_call_constructors_recursive(si);
+
+#if ALLOW_SYMBOLS_FROM_MAIN
+    /* Set apkenv_somain after we've loaded all the libraries in order to prevent
+     * linking of symbols back to the main image, which is not set up at that
+     * point yet.
+     */
+    apkenv_somain = si;
+#endif
+
+#if TIMING
+    gettimeofday(&t1,NULL);
+    PRINT("LINKER TIME: %s: %d microseconds\n", argv[0], (int) (
+               (((long long)t1.tv_sec * 1000000LL) + (long long)t1.tv_usec) -
+               (((long long)t0.tv_sec * 1000000LL) + (long long)t0.tv_usec)
+               ));
+#endif
+#if STATS
+    PRINT("RELO STATS: %s: %d abs, %d rel, %d copy, %d symbol\n", argv[0],
+           apkenv_linker_stats.reloc[RELOC_ABSOLUTE],
+           apkenv_linker_stats.reloc[RELOC_RELATIVE],
+           apkenv_linker_stats.reloc[RELOC_COPY],
+           apkenv_linker_stats.reloc[RELOC_SYMBOL]);
+#endif
+#if COUNT_PAGES
+    {
+        unsigned n;
+        unsigned i;
+        unsigned count = 0;
+        for(n = 0; n < 4096; n++){
+            if(apkenv_bitmask[n]){
+                unsigned x = apkenv_bitmask[n];
+                for(i = 0; i < 8; i++){
+                    if(x & 1) count++;
+                    x >>= 1;
+                }
+            }
+        }
+        PRINT("PAGES MODIFIED: %s: %d (%dKB)\n", argv[0], count, count * 4);
+    }
+#endif
+
+#if TIMING || STATS || COUNT_PAGES
+    fflush(stdout);
+#endif
+
+    TRACE("[ %5d Ready to execute '%s' @ 0x%08x ]\n", apkenv_pid, si->name,
+          si->entry);
+    return si->entry;
+}
+
+/*
+ * Find the value of AT_BASE passed to us by the kernel. This is the load
+ * location of the linker.
+ */
+static unsigned apkenv_find_linker_base(unsigned **elfdata) {
+    int argc = (int)(intptr_t)*elfdata;
+    char **argv = (char**) (elfdata + 1);
+    unsigned *vecs = (unsigned*) (argv + argc + 1);
+    while (vecs[0] != 0) {
+        vecs++;
+    }
+
+    /* The end of the environment block is marked by two NULL pointers */
+    vecs++;
+
+    while(vecs[0]) {
+        if (vecs[0] == AT_BASE) {
+            return vecs[1];
+        }
+        vecs += 2;
+    }
+
+    return 0; // should never happen
+}
+
+/*
+ * This is the entry point for the linker, called from begin.S. This
+ * method is responsible for fixing the linker's own relocations, and
+ * then calling apkenv___linker_init_post_relocation().
+ *
+ * Because this method is called before the linker has fixed it's own
+ * relocations, any attempt to reference an extern variable, extern
+ * function, or other GOT reference will generate a segfault.
+ */
+unsigned apkenv___linker_init(unsigned **elfdata) {
+    unsigned linker_addr = apkenv_find_linker_base(elfdata);
+    Elf32_Ehdr *elf_hdr = (Elf32_Ehdr *)(intptr_t)linker_addr;
+    Elf32_Phdr *phdr =
+        (Elf32_Phdr *)((unsigned char *)(intptr_t)linker_addr + elf_hdr->e_phoff);
+
+    soinfo linker_so;
+    memset(&linker_so, 0, sizeof(soinfo));
+
+    linker_so.base = linker_addr;
+    linker_so.dynamic = (unsigned *) -1;
+    linker_so.phdr = phdr;
+    linker_so.phnum = elf_hdr->e_phnum;
+    linker_so.flags |= FLAG_LINKER;
+    linker_so.wrprotect_start = 0xffffffff;
+    linker_so.wrprotect_end = 0;
+    linker_so.gnu_relro_start = 0;
+    linker_so.gnu_relro_len = 0;
+    if (apkenv_link_image(&linker_so, 0)) {
+        // It would be nice to print an error message, but if the linker
+        // can't link itself, there's no guarantee that we'll be able to
+        // call write() (because it involves a GOT reference).
+        //
+        // This situation should never occur unless the linker itself
+        // is corrupt.
+        exit(-1);
+    }
+
+    // We have successfully fixed our own relocations. It's safe to run
+    // the main part of the linker now.
+    return apkenv___linker_init_post_relocation(elfdata);
+}
diff --git a/src/linker/linker.h b/src/linker/linker.h
new file mode 100644
index 0000000..13d9bff
--- /dev/null
+++ b/src/linker/linker.h
@@ -0,0 +1,226 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _LINKER_H_
+#define _LINKER_H_
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <elf.h>
+#include <link.h>
+
+#undef PAGE_MASK
+#undef PAGE_SIZE
+#define PAGE_SIZE 4096
+#define PAGE_MASK 4095
+
+void apkenv_debugger_init();
+
+/* magic shared structures that GDB knows about */
+
+#if 0
+struct link_map
+{
+    uintptr_t l_addr;
+    char * l_name;
+    uintptr_t l_ld;
+    struct link_map * l_next;
+    struct link_map * l_prev;
+};
+
+/* needed for dl_iterate_phdr to be passed to the callbacks provided */
+struct dl_phdr_info
+{
+    Elf32_Addr dlpi_addr;
+    const char *dlpi_name;
+    const Elf32_Phdr *dlpi_phdr;
+    Elf32_Half dlpi_phnum;
+};
+
+
+// Values for r_debug->state
+enum {
+    RT_CONSISTENT,
+    RT_ADD,
+    RT_DELETE
+};
+
+struct r_debug
+{
+    int32_t r_version;
+    struct link_map * r_map;
+    void (*r_brk)(void);
+    int32_t r_state;
+    uintptr_t r_ldbase;
+};
+#endif
+
+typedef struct soinfo soinfo;
+
+#define FLAG_LINKED     0x00000001
+#define FLAG_ERROR      0x00000002
+#define FLAG_EXE        0x00000004 // The main executable
+#define FLAG_LINKER     0x00000010 // The linker itself
+
+#define SOINFO_NAME_LEN 128
+
+struct soinfo
+{
+    const char name[SOINFO_NAME_LEN];
+    Elf32_Phdr *phdr;
+    int phnum;
+    unsigned entry;
+    unsigned base;
+    unsigned size;
+
+    int unused;  // DO NOT USE, maintained for compatibility.
+
+    unsigned *dynamic;
+
+    unsigned wrprotect_start;
+    unsigned wrprotect_end;
+
+    soinfo *next;
+    unsigned flags;
+
+    const char *strtab;
+    Elf32_Sym *symtab;
+
+    unsigned nbucket;
+    unsigned nchain;
+    unsigned *bucket;
+    unsigned *chain;
+
+    unsigned *plt_got;
+
+    Elf32_Rel *plt_rel;
+    unsigned plt_rel_count;
+
+    Elf32_Rel *rel;
+    unsigned rel_count;
+
+    unsigned *preinit_array;
+    unsigned preinit_array_count;
+
+    unsigned *init_array;
+    unsigned init_array_count;
+    unsigned *fini_array;
+    unsigned fini_array_count;
+
+    void (*init_func)(void);
+    void (*fini_func)(void);
+
+#ifdef ANDROID_ARM_LINKER
+    /* ARM EABI section used for stack unwinding. */
+    unsigned *ARM_exidx;
+    unsigned ARM_exidx_count;
+#endif
+
+    unsigned refcount;
+    struct link_map linkmap;
+
+    int constructors_called;
+
+    Elf32_Addr gnu_relro_start;
+    unsigned gnu_relro_len;
+
+    /* apkenv stuff */
+    char fullpath[SOINFO_NAME_LEN];
+};
+
+
+extern soinfo apkenv_libdl_info;
+
+#ifdef ANDROID_ARM_LINKER
+
+#define R_ARM_COPY       20
+#define R_ARM_GLOB_DAT   21
+#define R_ARM_JUMP_SLOT  22
+#define R_ARM_RELATIVE   23
+
+/* According to the AAPCS specification, we only
+ * need the above relocations. However, in practice,
+ * the following ones turn up from time to time.
+ */
+#define R_ARM_ABS32      2
+#define R_ARM_REL32      3
+
+#elif defined(ANDROID_X86_LINKER)
+
+#define R_386_32         1
+#define R_386_PC32       2
+#define R_386_GLOB_DAT   6
+#define R_386_JUMP_SLOT  7
+#define R_386_RELATIVE   8
+
+#endif
+
+#ifndef DT_INIT_ARRAY
+#define DT_INIT_ARRAY      25
+#endif
+
+#ifndef DT_FINI_ARRAY
+#define DT_FINI_ARRAY      26
+#endif
+
+#ifndef DT_INIT_ARRAYSZ
+#define DT_INIT_ARRAYSZ    27
+#endif
+
+#ifndef DT_FINI_ARRAYSZ
+#define DT_FINI_ARRAYSZ    28
+#endif
+
+#ifndef DT_PREINIT_ARRAY
+#define DT_PREINIT_ARRAY   32
+#endif
+
+#ifndef DT_PREINIT_ARRAYSZ
+#define DT_PREINIT_ARRAYSZ 33
+#endif
+
+soinfo *apkenv_find_library(const char *name);
+unsigned apkenv_unload_library(soinfo *si);
+Elf32_Sym *apkenv_lookup_in_library(soinfo *si, const char *name);
+Elf32_Sym *apkenv_lookup(const char *name, soinfo **found, soinfo *start);
+soinfo *apkenv_find_containing_library(const void *addr);
+Elf32_Sym *apkenv_find_containing_symbol(const void *addr, soinfo *si);
+const char *apkenv_linker_get_error(void);
+void apkenv_call_constructors_recursive(soinfo *si);
+
+#ifdef ANDROID_ARM_LINKER
+typedef long unsigned int *_Unwind_Ptr;
+_Unwind_Ptr apkenv_dl_unwind_find_exidx(_Unwind_Ptr pc, int *pcount);
+#elif defined(ANDROID_X86_LINKER)
+int apkenv_dl_iterate_phdr(int (*cb)(struct dl_phdr_info *, size_t, void *), void *);
+#endif
+
+void apkenv_notify_gdb_of_libraries(void);
+int apkenv_add_sopath(const char *path);
+
+#endif
diff --git a/src/linker/linker_debug.h b/src/linker/linker_debug.h
new file mode 100644
index 0000000..2ab7a40
--- /dev/null
+++ b/src/linker/linker_debug.h
@@ -0,0 +1,154 @@
+/*
+ * Copyright (C) 2008-2010 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _LINKER_DEBUG_H_
+#define _LINKER_DEBUG_H_
+
+#include <stdio.h>
+
+#ifndef LINKER_DEBUG
+#error LINKER_DEBUG should be defined to either 1 or 0 in Android.mk
+#endif
+
+/* set LINKER_DEBUG_TO_LOG to 1 to send the logs to logcat,
+ * or 0 to use stdout instead.
+ */
+#define LINKER_DEBUG_TO_LOG  0
+#define TRACE_DEBUG          1
+#define DO_TRACE_LOOKUP      1
+#define DO_TRACE_RELO        1
+#define TIMING               0
+#define STATS                0
+#define COUNT_PAGES          0
+
+/*********************************************************************
+ * You shouldn't need to modify anything below unless you are adding
+ * more debugging information.
+ *
+ * To enable/disable specific debug options, change the defines above
+ *********************************************************************/
+
+
+/*********************************************************************/
+#undef TRUE
+#undef FALSE
+#define TRUE                 1
+#define FALSE                0
+
+/* Only use printf() during debugging.  We have seen occasional memory
+ * corruption when the linker uses printf().
+ */
+#if LINKER_DEBUG
+#include "linker_format.h"
+extern int apkenv_debug_verbosity;
+#if LINKER_DEBUG_TO_LOG
+extern int apkenv_format_log(int, const char *, const char *, ...);
+#define _PRINTVF(v,f,x...)                                        \
+    do {                                                          \
+        if (apkenv_debug_verbosity > (v)) apkenv_format_log(5-(v),"linker",x);  \
+    } while (0)
+#else /* !LINKER_DEBUG_TO_LOG */
+#define _PRINTVF(v,f,x...)                           \
+    do {                                             \
+        if (apkenv_debug_verbosity > (v)) printf(x);        \
+    } while (0)
+#endif /* !LINKER_DEBUG_TO_LOG */
+#else /* !LINKER_DEBUG */
+#define _PRINTVF(v,f,x...)   do {} while(0)
+#endif /* LINKER_DEBUG */
+
+#define PRINT(x...)          _PRINTVF(-1, FALSE, x)
+#define INFO(x...)           _PRINTVF(1, TRUE, x)
+#define TRACE(x...)          _PRINTVF(1, TRUE, x)
+#define WARN(fmt,args...)    \
+        _PRINTVF(-1, TRUE, "%s:%d| WARNING: " fmt, __FILE__, __LINE__, ## args)
+#define ERROR(fmt,args...)    \
+        printf("%s:%d| ERROR: " fmt, __FILE__, __LINE__, ## args)
+
+
+#if TRACE_DEBUG
+#define DEBUG(x...)          _PRINTVF(2, TRUE, "DEBUG: " x)
+#else /* !TRACE_DEBUG */
+#define DEBUG(x...)          do {} while (0)
+#endif /* TRACE_DEBUG */
+
+#if LINKER_DEBUG
+#define TRACE_TYPE(t,x...)   do { if (DO_TRACE_##t) { TRACE(x); } } while (0)
+#else  /* !LINKER_DEBUG */
+#define TRACE_TYPE(t,x...)   do {} while (0)
+#endif /* LINKER_DEBUG */
+
+#if STATS
+#define RELOC_ABSOLUTE        0
+#define RELOC_RELATIVE        1
+#define RELOC_COPY            2
+#define RELOC_SYMBOL          3
+#define NUM_RELOC_STATS       4
+
+struct _link_stats {
+    int reloc[NUM_RELOC_STATS];
+};
+extern struct _link_stats apkenv_linker_stats;
+
+#define COUNT_RELOC(type)                                 \
+        do { if (type >= 0 && type < NUM_RELOC_STATS) {   \
+                apkenv_linker_stats.reloc[type] += 1;            \
+             } else  {                                    \
+                PRINT("Unknown reloc stat requested\n");  \
+             }                                            \
+           } while(0)
+#else /* !STATS */
+#define COUNT_RELOC(type)     do {} while(0)
+#endif /* STATS */
+
+#if TIMING
+#undef WARN
+#define WARN(x...)           do {} while (0)
+#endif /* TIMING */
+
+#if COUNT_PAGES
+extern unsigned apkenv_bitmask[];
+#define MARK(offset)         do {                                        \
+        apkenv_bitmask[((offset) >> 12) >> 3] |= (1 << (((offset) >> 12) & 7)); \
+    } while(0)
+#else
+#define MARK(x)              do {} while (0)
+#endif
+
+#define DEBUG_DUMP_PHDR(phdr, name, pid) do { \
+        DEBUG("%5d %s (phdr = 0x%08x)\n", (pid), (name), (unsigned)(phdr));   \
+        DEBUG("\t\tphdr->offset   = 0x%08x\n", (unsigned)((phdr)->p_offset)); \
+        DEBUG("\t\tphdr->p_vaddr  = 0x%08x\n", (unsigned)((phdr)->p_vaddr));  \
+        DEBUG("\t\tphdr->p_paddr  = 0x%08x\n", (unsigned)((phdr)->p_paddr));  \
+        DEBUG("\t\tphdr->p_filesz = 0x%08x\n", (unsigned)((phdr)->p_filesz)); \
+        DEBUG("\t\tphdr->p_memsz  = 0x%08x\n", (unsigned)((phdr)->p_memsz));  \
+        DEBUG("\t\tphdr->p_flags  = 0x%08x\n", (unsigned)((phdr)->p_flags));  \
+        DEBUG("\t\tphdr->p_align  = 0x%08x\n", (unsigned)((phdr)->p_align));  \
+    } while (0)
+
+#endif /* _LINKER_DEBUG_H_ */
diff --git a/src/linker/linker_environ.c b/src/linker/linker_environ.c
new file mode 100644
index 0000000..ca8b1d9
--- /dev/null
+++ b/src/linker/linker_environ.c
@@ -0,0 +1,204 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#include "linker_environ.h"
+#include <stddef.h>
+
+static char** apkenv__envp;
+
+/* Returns 1 if 'str' points to a valid environment variable definition.
+ * For now, we check that:
+ *  - It is smaller than MAX_ENV_LEN (to detect non-zero terminated strings)
+ *  - It contains at least one equal sign that is not the first character
+ */
+static int
+apkenv__is_valid_definition(const char*  str)
+{
+    int   pos = 0;
+    int   first_equal_pos = -1;
+
+    /* According to its sources, the kernel uses 32*PAGE_SIZE by default
+     * as the maximum size for an env. variable definition.
+     */
+    const int MAX_ENV_LEN = 32*4096;
+
+    if (str == NULL)
+        return 0;
+
+    /* Parse the string, looking for the first '=' there, and its size */
+    do {
+        if (str[pos] == '\0')
+            break;
+        if (str[pos] == '=' && first_equal_pos < 0)
+            first_equal_pos = pos;
+        pos++;
+    } while (pos < MAX_ENV_LEN);
+
+    if (pos >= MAX_ENV_LEN)  /* Too large */
+        return 0;
+
+    if (first_equal_pos < 1)  /* No equal sign, or it is the first character */
+        return 0;
+
+    return 1;
+}
+
+unsigned*
+apkenv_linker_env_init(unsigned* vecs)
+{
+    /* Store environment pointer - can't be NULL */
+    apkenv__envp = (char**) vecs;
+
+    /* Skip over all definitions */
+    while (vecs[0] != 0)
+        vecs++;
+    /* The end of the environment block is marked by two NULL pointers */
+    vecs++;
+
+    /* As a sanity check, we're going to remove all invalid variable
+     * definitions from the environment array.
+     */
+    {
+        char** readp  = apkenv__envp;
+        char** writep = apkenv__envp;
+        for ( ; readp[0] != NULL; readp++ ) {
+            if (!apkenv__is_valid_definition(readp[0]))
+                continue;
+            writep[0] = readp[0];
+            writep++;
+        }
+        writep[0] = NULL;
+    }
+
+    /* Return the address of the aux vectors table */
+    return vecs;
+}
+
+/* Check if the environment variable definition at 'envstr'
+ * starts with '<name>=', and if so return the address of the
+ * first character after the equal sign. Otherwise return NULL.
+ */
+static char*
+apkenv_env_match(char* envstr, const char* name)
+{
+    size_t  cnt = 0;
+
+    while (envstr[cnt] == name[cnt] && name[cnt] != '\0')
+        cnt++;
+
+    if (name[cnt] == '\0' && envstr[cnt] == '=')
+        return envstr + cnt + 1;
+
+    return NULL;
+}
+
+#define MAX_ENV_LEN  (16*4096)
+
+const char*
+apkenv_linker_env_get(const char* name)
+{
+    char** readp = apkenv__envp;
+
+    if (name == NULL || name[0] == '\0')
+        return NULL;
+
+    for ( ; readp[0] != NULL; readp++ ) {
+        char* val = apkenv_env_match(readp[0], name);
+        if (val != NULL) {
+            /* Return NULL for empty strings, or if it is too large */
+            if (val[0] == '\0')
+                val = NULL;
+            return val;
+        }
+    }
+    return NULL;
+}
+
+
+void
+apkenv_linker_env_unset(const char* name)
+{
+    char**  readp = apkenv__envp;
+    char**  writep = readp;
+
+    if (name == NULL || name[0] == '\0')
+        return;
+
+    for ( ; readp[0] != NULL; readp++ ) {
+        if (apkenv_env_match(readp[0], name))
+            continue;
+        writep[0] = readp[0];
+        writep++;
+    }
+    /* end list with a NULL */
+    writep[0] = NULL;
+}
+
+
+
+/* Remove unsafe environment variables. This should be used when
+ * running setuid programs. */
+void
+apkenv_linker_env_secure(void)
+{
+    /* The same list than GLibc at this point */
+    static const char* const unsec_vars[] = {
+        "GCONV_PATH",
+        "GETCONF_DIR",
+        "HOSTALIASES",
+        "LD_AUDIT",
+        "LD_DEBUG",
+        "LD_DEBUG_OUTPUT",
+        "LD_DYNAMIC_WEAK",
+        "LD_LIBRARY_PATH",
+        "LD_ORIGIN_PATH",
+        "LD_PRELOAD",
+        "LD_PROFILE",
+        "LD_SHOW_AUXV",
+        "LD_USE_LOAD_BIAS",
+        "LOCALDOMAIN",
+        "LOCPATH",
+        "MALLOC_TRACE",
+        "MALLOC_CHECK_",
+        "NIS_PATH",
+        "NLSPATH",
+        "RESOLV_HOST_CONF",
+        "RES_OPTIONS",
+        "TMPDIR",
+        "TZDIR",
+        "LD_AOUT_LIBRARY_PATH",
+        "LD_AOUT_PRELOAD",
+    };
+
+    const char* const* cp   = unsec_vars;
+    const char* const* endp = cp + sizeof(unsec_vars)/sizeof(unsec_vars[0]);
+
+    while (cp < endp) {
+        apkenv_linker_env_unset(*cp);
+        cp++;
+    }
+}
diff --git a/src/linker/linker_environ.h b/src/linker/linker_environ.h
new file mode 100644
index 0000000..9bb24c4
--- /dev/null
+++ b/src/linker/linker_environ.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#ifndef LINKER_ENVIRON_H
+#define LINKER_ENVIRON_H
+
+/* Call this function before anything else. 'vecs' must be the pointer
+ * to the environment block in the ELF data block. The function returns
+ * the start of the aux vectors after the env block.
+ */
+extern unsigned*   apkenv_linker_env_init(unsigned* vecs);
+
+/* Unset a given environment variable. In case the variable is defined
+ * multiple times, unset all instances. This modifies the environment
+ * block, so any pointer returned by linker_env_get() after this call
+ * might become invalid */
+extern void        apkenv_linker_env_unset(const char* name);
+
+
+/* Returns the value of environment variable 'name' if defined and not
+ * empty, or NULL otherwise. Note that the returned pointer may become
+ * invalid if linker_env_unset() or linker_env_secure() are called
+ * after this function. */
+extern const char* apkenv_linker_env_get(const char* name);
+
+/* Remove unsecure environment variables. This should be used when
+ * running setuid programs. */
+extern void        apkenv_linker_env_secure(void);
+
+#endif /* LINKER_ENVIRON_H */
diff --git a/src/linker/linker_format.h b/src/linker/linker_format.h
new file mode 100644
index 0000000..e7b34b5
--- /dev/null
+++ b/src/linker/linker_format.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#ifndef _LINKER_FORMAT_H
+#define _LINKER_FORMAT_H
+
+#include <stdarg.h>
+#include <stddef.h>
+
+/* Formatting routines for the dynamic linker's debug traces */
+/* We want to avoid dragging the whole C library fprintf()   */
+/* implementation into the dynamic linker since this creates */
+/* issues (it uses malloc()/free()) and increases code size  */
+
+// apkenv: we can just use snprintf
+//int format_buffer(char *buffer, size_t bufsize, const char *format, ...);
+#define format_buffer snprintf
+
+#endif /* _LINKER_FORMAT_H */
diff --git a/src/linker/rt.c b/src/linker/rt.c
new file mode 100644
index 0000000..31db8ee
--- /dev/null
+++ b/src/linker/rt.c
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * This function is an empty stub where GDB locates a breakpoint to get notified
+ * about linker activity.
+ */
+void __attribute__((noinline)) apkenv_rtld_db_dlactivity(void)
+{
+}
+
diff --git a/src/linker/strlcpy.c b/src/linker/strlcpy.c
new file mode 100644
index 0000000..e0fd250
--- /dev/null
+++ b/src/linker/strlcpy.c
@@ -0,0 +1,50 @@
+/*	$OpenBSD: strlcpy.c,v 1.11 2006/05/05 15:27:38 millert Exp $	*/
+
+/*
+ * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "strlcpy.h"
+
+/*
+ * Copy src to string dst of size siz.  At most siz-1 characters
+ * will be copied.  Always NUL terminates (unless siz == 0).
+ * Returns strlen(src); if retval >= siz, truncation occurred.
+ */
+size_t
+apkenv_strlcpy(char *dst, const char *src, size_t siz)
+{
+	char *d = dst;
+	const char *s = src;
+	size_t n = siz;
+
+	/* Copy as many bytes as will fit */
+	if (n != 0) {
+		while (--n != 0) {
+			if ((*d++ = *s++) == '\0')
+				break;
+		}
+	}
+
+	/* Not enough room in dst, add NUL and traverse rest of src */
+	if (n == 0) {
+		if (siz != 0)
+			*d = '\0';		/* NUL-terminate dst */
+		while (*s++)
+			;
+	}
+
+	return(s - src - 1);	/* count does not include NUL */
+}
diff --git a/src/linker/strlcpy.h b/src/linker/strlcpy.h
new file mode 100644
index 0000000..a524530
--- /dev/null
+++ b/src/linker/strlcpy.h
@@ -0,0 +1,10 @@
+#ifndef STRLCPY_H
+#define STRLCPY_H
+
+#include <sys/types.h>
+#include <string.h>
+
+size_t
+apkenv_strlcpy(char *dst, const char *src, size_t siz);
+
+#endif