path: root/lib/libalpm/util.c

/*
 *  util.c
 *
 *  Copyright (c) 2002-2006 by Judd Vinet <jvinet@zeroflux.org>
 *  Copyright (c) 2005 by Aurelien Foret <orelien@chez.com>
 *  Copyright (c) 2005 by Christian Hamar <krics@linuxforum.hu>
 *  Copyright (c) 2006 by David Kimpe <dnaku@frugalware.org>
 *  Copyright (c) 2005, 2006 by Miklos Vajna <vmiklos@frugalware.org>
 * 
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 
 *  USA.
 */

#include "config.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <ctype.h>
#include <dirent.h>
#include <time.h>
#include <syslog.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>

/* libarchive */
#include <archive.h>
#include <archive_entry.h>

/* libalpm */
#include "util.h"
#include "log.h"
#include "error.h"
#include "package.h"
#include "alpm.h"
#include "alpm_list.h"
#include "md5.h"

#ifndef HAVE_STRVERSCMP
/* GNU's strverscmp() function, taken from glibc 2.3.2 sources
 */

/* Compare strings while treating digits characters numerically.
   Copyright (C) 1997, 2002 Free Software Foundation, Inc.
   Contributed by Jean-François Bignolles <bignolle@ecoledoc.ibp.fr>, 1997.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.
*/

/* states: S_N: normal, S_I: comparing integral part, S_F: comparing
           fractionnal parts, S_Z: idem but with leading Zeroes only */
#define  S_N    0x0
#define  S_I    0x4
#define  S_F    0x8
#define  S_Z    0xC

/* result_type: CMP: return diff; LEN: compare using len_diff/diff */
#define  CMP    2
#define  LEN    3

/* Compare S1 and S2 as strings holding indices/version numbers,
   returning less than, equal to or greater than zero if S1 is less than,
   equal to or greater than S2 (for more info, see the texinfo doc).
*/

int strverscmp (s1, s2)
     const char *s1;
     const char *s2;
{
  const unsigned char *p1 = (const unsigned char *) s1;
  const unsigned char *p2 = (const unsigned char *) s2;
  unsigned char c1, c2;
  int state;
  int diff;

  /* Symbol(s)    0       [1-9]   others  (padding)
     Transition   (10) 0  (01) d  (00) x  (11) -   */
  static const unsigned int next_state[] =
  {
      /* state    x    d    0    - */
      /* S_N */  S_N, S_I, S_Z, S_N,
      /* S_I */  S_N, S_I, S_I, S_I,
      /* S_F */  S_N, S_F, S_F, S_F,
      /* S_Z */  S_N, S_F, S_Z, S_Z
  };

  static const int result_type[] =
  {
      /* state   x/x  x/d  x/0  x/-  d/x  d/d  d/0  d/-
                 0/x  0/d  0/0  0/-  -/x  -/d  -/0  -/- */

      /* S_N */  CMP, CMP, CMP, CMP, CMP, LEN, CMP, CMP,
                 CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
      /* S_I */  CMP, -1,  -1,  CMP, +1,  LEN, LEN, CMP,
                 +1,  LEN, LEN, CMP, CMP, CMP, CMP, CMP,
      /* S_F */  CMP, CMP, CMP, CMP, CMP, LEN, CMP, CMP,
                 CMP, CMP, CMP, CMP, CMP, CMP, CMP, CMP,
      /* S_Z */  CMP, +1,  +1,  CMP, -1,  CMP, CMP, CMP,
                 -1,  CMP, CMP, CMP
  };

  if (p1 == p2)
    return 0;

  c1 = *p1++;
  c2 = *p2++;
  /* Hint: '0' is a digit too.  */
  state = S_N | ((c1 == '0') + (isdigit (c1) != 0));

  while ((diff = c1 - c2) == 0 && c1 != '\0')
    {
      state = next_state[state];
      c1 = *p1++;
      c2 = *p2++;
      state |= (c1 == '0') + (isdigit (c1) != 0);
    }

  state = result_type[state << 2 | (((c2 == '0') + (isdigit (c2) != 0)))];

  switch (state)
  {
    case CMP:
      return diff;

    case LEN:
      while (isdigit (*p1++))
  if (!isdigit (*p2++))
    return 1;

      return isdigit (*p2) ? -1 : diff;

    default:
      return state;
  }
}
#endif

#ifndef HAVE_STRSEP
/* This is a replacement for strsep which is not portable (missing on Solaris).
 * Copyright (c) 2001 by François Gouget <fgouget_at_codeweavers.com> */
char* strsep(char** str, const char* delims)
{
  char* token;

  if (*str==NULL) {
    /* No more tokens */
    return NULL;
  }

  token=*str;
  while (**str!='\0') {
    if (strchr(delims,**str)!=NULL) {
      **str='\0';
      (*str)++;
      return token;
    }
    (*str)++;
  }
  /* There is no other token */
  *str=NULL;
  return token;
}
#endif

/* does the same thing as 'mkdir -p' */
int _alpm_makepath(const char *path)
{
  char *orig, *str, *ptr;
  char full[PATH_MAX] = "";
  mode_t oldmask;

  oldmask = umask(0000);

  orig = strdup(path);
  str = orig;
  while((ptr = strsep(&str, "/"))) {
    if(strlen(ptr)) {
      struct stat buf;

      strcat(full, "/");
      strcat(full, ptr);
      if(stat(full, &buf)) {
        if(mkdir(full, 0755)) {
          FREE(orig);
          umask(oldmask);
          _alpm_log(PM_LOG_ERROR, _("failed to make path '%s' : %s\n"),
                    path, strerror(errno));
          return(1);
        }
      }
    }
  }
  FREE(orig);
  umask(oldmask);
  return(0);
}

int _alpm_copyfile(const char *src, const char *dest)
{
  FILE *in, *out;
  size_t len;
  char buf[4097];

  in = fopen(src, "r");
  if(in == NULL) {
    return(1);
  }
  out = fopen(dest, "w");
  if(out == NULL) {
    fclose(in);
    return(1);
  }

  /* do the actual file copy */
  while((len = fread(buf, 1, 4096, in))) {
    fwrite(buf, 1, len, out);
  }
  fclose(in);

  /* chmod dest to permissions of src, as long as it is not a symlink */
  struct stat statbuf;
  if(!stat(src, &statbuf)) {
    if(! S_ISLNK(statbuf.st_mode)) {
      fchmod(fileno(out), statbuf.st_mode);
    }
  } else {
    /* stat was unsuccessful */
    fclose(out);
    return(1);
  }

  fclose(out);
  return(0);
}

/* Trim whitespace and newlines from a string
*/
char *_alpm_strtrim(char *str)
{
  char *pch = str;

  if(*str == '\0') {
    /* string is empty, so we're done. */
    return(str);
  }

  while(isspace((int)*pch)) {
    pch++;
  }
  if(pch != str) {
    memmove(str, pch, (strlen(pch) + 1));
  }

  /* check if there wasn't anything but whitespace in the string. */
  if(*str == '\0') {
    return(str);
  }

  pch = (str + (strlen(str) - 1));
  while(isspace((int)*pch)) {
    pch--;
  }
  *++pch = '\0';

  return(str);
}

/* Helper function for _alpm_strreplace */
static void _strnadd(char **str, const char *append, unsigned int count)
{
  if(*str) {
    *str = realloc(*str, strlen(*str) + count + 1);
  } else {
    *str = calloc(count + 1, sizeof(char));
  }

  strncat(*str, append, count);
}

/* Replace all occurances of 'needle' with 'replace' in 'str', returning
 * a new string (must be free'd) */
char *_alpm_strreplace(const char *str, const char *needle, const char *replace)
{
  const char *p, *q;
  p = q = str;

  char *newstr = NULL;
  unsigned int needlesz = strlen(needle),
               replacesz = strlen(replace);

  while (1) {
    q = strstr(p, needle);
    if(!q) { /* not found */ 
      if(*p) {
        /* add the rest of 'p' */
        _strnadd(&newstr, p, strlen(p));
      }
      break;
    } else { /* found match */
      if(q > p){
        /* add chars between this occurance and last occurance, if any */
        _strnadd(&newstr, p, q - p);
      }
      _strnadd(&newstr, replace, replacesz);
      p = q + needlesz;
    }
  }

  return newstr;
}


/* Create a lock file */
int _alpm_lckmk()
{
  int fd, count = 0;
  char *dir, *ptr;
  const char *file = alpm_option_get_lockfile();

  /* create the dir of the lockfile first */
  dir = strdup(file);
  ptr = strrchr(dir, '/');
  if(ptr) {
    *ptr = '\0';
  }
  _alpm_makepath(dir);

  while((fd = open(file, O_WRONLY | O_CREAT | O_EXCL, 0000)) == -1 && errno == EACCES) { 
    if(++count < 1) {
      sleep(1);
    } else {
      return(-1);
    }
  }

  FREE(dir);

  return(fd > 0 ? fd : -1);
}

/* Remove a lock file */
int _alpm_lckrm()
{
  const char *file = alpm_option_get_lockfile();
  if(unlink(file) == -1 && errno != ENOENT) {
    return(-1);
  }
  return(0);
}

/* Compression functions */

int _alpm_unpack(const char *archive, const char *prefix, const char *fn)
{
  register struct archive *_archive;
  struct archive_entry *entry;
  char expath[PATH_MAX];
  const int archive_flags = ARCHIVE_EXTRACT_OWNER |
    ARCHIVE_EXTRACT_PERM |
    ARCHIVE_EXTRACT_TIME;

  ALPM_LOG_FUNC;

  if((_archive = archive_read_new()) == NULL)
    RET_ERR(PM_ERR_LIBARCHIVE_ERROR, -1);

  archive_read_support_compression_all(_archive);
  archive_read_support_format_all(_archive);

  if(archive_read_open_filename(_archive, archive,
        ARCHIVE_DEFAULT_BYTES_PER_BLOCK) != ARCHIVE_OK) {
    _alpm_log(PM_LOG_ERROR, _("could not open %s: %s\n"), archive,
        archive_error_string(_archive));
    RET_ERR(PM_ERR_PKG_OPEN, -1);
  }

  while(archive_read_next_header(_archive, &entry) == ARCHIVE_OK) {
    const char *entryname; /* the name of the file in the archive */
    entryname = archive_entry_pathname(entry);

    if (fn && strcmp(fn, entryname)) {
      if (archive_read_data_skip(_archive) != ARCHIVE_OK)
        return(1);
      continue;
    }
    snprintf(expath, PATH_MAX, "%s/%s", prefix, entryname);
    archive_entry_set_pathname(entry, expath);
    int ret = archive_read_extract(_archive, entry, archive_flags);
    if(ret == ARCHIVE_WARN) {
      /* operation succeeded but a non-critical error was encountered */
      _alpm_log(PM_LOG_DEBUG, "warning extracting %s (%s)\n",
          entryname, archive_error_string(_archive));
    } else if(ret != ARCHIVE_OK) {
      _alpm_log(PM_LOG_ERROR, _("could not extract %s (%s)\n"),
          entryname, archive_error_string(_archive));
      return(1);
    }

    if(fn) {
      break;
    }
  }

  archive_read_finish(_archive);
  return(0);
}

/* does the same thing as 'rm -rf' */
int _alpm_rmrf(const char *path)
{
  int errflag = 0;
  struct dirent *dp;
  DIR *dirp;
  char name[PATH_MAX];
  struct stat st;

  if(lstat(path, &st) == 0) {
    if(!S_ISDIR(st.st_mode)) {
      if(!unlink(path)) {
        return(0);
      } else {
        if(errno == ENOENT) {
          return(0);
        } else {
          return(1);
        }
      }
    } else {
      if((dirp = opendir(path)) == (DIR *)-1) {
        return(1);
      }
      for(dp = readdir(dirp); dp != NULL; dp = readdir(dirp)) {
        if(dp->d_ino) {
          sprintf(name, "%s/%s", path, dp->d_name);
          if(strcmp(dp->d_name, "..") && strcmp(dp->d_name, ".")) {
            errflag += _alpm_rmrf(name);
          }
        }
      }
      closedir(dirp);
      if(rmdir(path)) {
        errflag++;
      }
    }
    return(errflag);
  }
  return(0);
}

int _alpm_logaction(unsigned short usesyslog, FILE *f, const char *fmt, va_list args)
{
  int ret = 0;

  if(usesyslog) {
    vsyslog(LOG_WARNING, fmt, args);
  }

  if(f) {
    time_t t;
    struct tm *tm;

    t = time(NULL);
    tm = localtime(&t);

    /* Use ISO-8601 date format */
    fprintf(f, "[%04d-%02d-%02d %02d:%02d] ",
            tm->tm_year+1900, tm->tm_mon+1, tm->tm_mday,
            tm->tm_hour, tm->tm_min);
    ret = vfprintf(f, fmt, args);
    fprintf(f, "\n");
    fflush(f);
  }

  return(ret);
}

int _alpm_ldconfig(const char *root)
{
  char line[PATH_MAX];
  struct stat buf;

  snprintf(line, PATH_MAX, "%setc/ld.so.conf", root);
  if(stat(line, &buf) == 0) {
    snprintf(line, PATH_MAX, "%ssbin/ldconfig", root);
    if(stat(line, &buf) == 0) {
      char cmd[PATH_MAX];
      snprintf(cmd, PATH_MAX, "%s -r %s", line, root);
      system(cmd);
    }
  }

  return(0);
}

/* convert a time_t to a string - buffer MUST be large enough for
 * YYYYMMDDHHMMSS - 15 chars */
void _alpm_time2string(time_t t, char *buffer)
{
  if(buffer) {
    struct tm *lt;
    lt = localtime(&t);
    sprintf(buffer, "%4d%02d%02d%02d%02d%02d",
            lt->tm_year+1900, lt->tm_mon+1, lt->tm_mday,
            lt->tm_hour, lt->tm_min, lt->tm_sec);
    buffer[14] = '\0';
  }
}

/* Helper function for comparing strings using the
 * alpm "compare func" signature */
int _alpm_str_cmp(const void *s1, const void *s2)
{
  return(strcmp(s1, s2));
}

/** Find a package file in an alpm cachedir.
 * @param filename name of package file to find
 * @return malloced path of file, NULL if not found
 */
char *_alpm_filecache_find(const char* filename)
{
  struct stat buf;
  char path[PATH_MAX];
  char *retpath;
  alpm_list_t *i;

  /* Loop through the cache dirs until we find a matching file */
  for(i = alpm_option_get_cachedirs(); i; i = alpm_list_next(i)) {
    snprintf(path, PATH_MAX, "%s%s", (char*)alpm_list_getdata(i),
        filename);
    if(stat(path, &buf) == 0) {
      /* TODO maybe check to make sure it is readable? */
      retpath = strdup(path);
      _alpm_log(PM_LOG_DEBUG, "found cached pkg: %s\n", retpath);
      return(retpath);
    }
  }
  /* package wasn't found in any cachedir */
  return(NULL);
}

/** Check the alpm cachedirs for existance and find a writable one.
 * If no valid cache directory can be found, use /tmp.
 * @return pointer to a writable cache directory.
 */
const char *_alpm_filecache_setup(void)
{
  struct stat buf;
  alpm_list_t *i, *tmp;
  char *cachedir;

  /* Loop through the cache dirs until we find a writeable dir */
  for(i = alpm_option_get_cachedirs(); i; i = alpm_list_next(i)) {
    cachedir = alpm_list_getdata(i);
    if(stat(cachedir, &buf) != 0) {
      /* cache directory does not exist.... try creating it */
      _alpm_log(PM_LOG_WARNING, _("no %s cache exists, creating...\n"),
          cachedir);
      alpm_logaction("warning: no %s cache exists, creating...",
          cachedir);
      if(_alpm_makepath(cachedir) == 0) {
        _alpm_log(PM_LOG_DEBUG, "using cachedir: %s\n", cachedir);
        return(cachedir);
      }
    } else if(S_ISDIR(buf.st_mode) && (buf.st_mode & S_IWUSR)) {
      _alpm_log(PM_LOG_DEBUG, "using cachedir: %s\n", cachedir);
      return(cachedir);
    }
  }

  /* we didn't find a valid cache directory. use /tmp. */
  i = alpm_option_get_cachedirs();
  tmp = alpm_list_add(NULL, strdup("/tmp/"));
  FREELIST(i);
  alpm_option_set_cachedirs(tmp);
  _alpm_log(PM_LOG_DEBUG, "using cachedir: %s", "/tmp/\n");
  _alpm_log(PM_LOG_WARNING, _("couldn't create package cache, using /tmp instead\n"));
  alpm_logaction("warning: couldn't create package cache, using /tmp instead");
  return(alpm_list_getdata(tmp));
}

/** Get the md5 sum of file.
 * @param filename name of the file
 * @return the checksum on success, NULL on error
 * @addtogroup alpm_misc
 */
char SYMEXPORT *alpm_get_md5sum(const char *filename)
{
  unsigned char output[16];
  char *md5sum;
  int ret, i;

  ALPM_LOG_FUNC;

  ASSERT(filename != NULL, return(NULL));

  /* allocate 32 chars plus 1 for null */
  md5sum = calloc(33, sizeof(char));
  ret = md5_file(filename, output);

  if (ret > 0) {
    if (ret == 1) {
      _alpm_log(PM_LOG_ERROR, _("md5: %s can't be opened\n"), filename);
    } else if (ret == 2) {
      _alpm_log(PM_LOG_ERROR, _("md5: %s can't be read\n"), filename);
    }

    return(NULL);
  }

  /* Convert the result to something readable */
  for (i = 0; i < 16; i++) {
    /* sprintf is acceptable here because we know our output */
    sprintf(md5sum +(i * 2), "%02x", output[i]);
  }
  md5sum[32] = '\0';

  _alpm_log(PM_LOG_DEBUG, "md5(%s) = %s\n", filename, md5sum);
  return(md5sum);
}

/* vim: set ts=2 sw=2 noet: */