summaryrefslogtreecommitdiff
path: root/jni/ruby/dln_find.c
blob: 895960928556e4d101c7215c3d2600a086095f8c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
/**********************************************************************

  dln_find.c -

  $Author: nobu $
  created at: Tue Jan 18 17:05:06 JST 1994

  Copyright (C) 1993-2007 Yukihiro Matsumoto

**********************************************************************/

#ifdef RUBY_EXPORT
#include "ruby/ruby.h"
#define dln_warning rb_warning
#define dln_warning_arg
#else
#define dln_warning fprintf
#define dln_warning_arg stderr,
#endif
#include "dln.h"

#ifdef HAVE_STDLIB_H
# include <stdlib.h>
#endif

#ifdef USE_DLN_A_OUT
char *dln_argv0;
#endif

#if defined(HAVE_ALLOCA_H)
#include <alloca.h>
#endif

#ifdef HAVE_STRING_H
# include <string.h>
#else
# include <strings.h>
#endif

#include <stdio.h>
#if defined(_WIN32)
#include "missing/file.h"
#endif
#include <sys/types.h>
#include <sys/stat.h>

#ifndef S_ISDIR
#   define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#endif

#ifdef HAVE_SYS_PARAM_H
# include <sys/param.h>
#endif
#ifndef MAXPATHLEN
# define MAXPATHLEN 1024
#endif

#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif

#if !defined(_WIN32) && !HAVE_DECL_GETENV
char *getenv();
#endif

static char *dln_find_1(const char *fname, const char *path, char *buf, size_t size, int exe_flag
                        DLN_FIND_EXTRA_ARG_DECL);

char *
dln_find_exe_r(const char *fname, const char *path, char *buf, size_t size
               DLN_FIND_EXTRA_ARG_DECL)
{
    char *envpath = 0;

    if (!path) {
        path = getenv(PATH_ENV);
        if (path) path = envpath = strdup(path);
    }

    if (!path) {
        path =
            "/usr/local/bin" PATH_SEP
            "/usr/ucb" PATH_SEP
            "/usr/bin" PATH_SEP
            "/bin" PATH_SEP
            ".";
    }
    buf = dln_find_1(fname, path, buf, size, 1 DLN_FIND_EXTRA_ARG);
    if (envpath) free(envpath);
    return buf;
}

char *
dln_find_file_r(const char *fname, const char *path, char *buf, size_t size
                DLN_FIND_EXTRA_ARG_DECL)
{
    if (!path) path = ".";
    return dln_find_1(fname, path, buf, size, 0 DLN_FIND_EXTRA_ARG);
}

static char *
dln_find_1(const char *fname, const char *path, char *fbuf, size_t size,
           int exe_flag /* non 0 if looking for executable. */
           DLN_FIND_EXTRA_ARG_DECL)
{
    register const char *dp;
    register const char *ep;
    register char *bp;
    struct stat st;
    size_t i, fnlen, fspace;
#ifdef DOSISH
    static const char extension[][5] = {
        EXECUTABLE_EXTS,
    };
    size_t j;
    int is_abs = 0, has_path = 0;
    const char *ext = 0;
#endif
    const char *p = fname;

    static const char pathname_too_long[] = "openpath: pathname too long (ignored)\n\
\tDirectory \"%.*s\"%s\n\tFile \"%.*s\"%s\n";
#define PATHNAME_TOO_LONG() dln_warning(dln_warning_arg pathname_too_long, \
                                        ((bp - fbuf) > 100 ? 100 : (int)(bp - fbuf)), fbuf, \
                                        ((bp - fbuf) > 100 ? "..." : ""), \
                                        (fnlen > 100 ? 100 : (int)fnlen), fname, \
                                        (fnlen > 100 ? "..." : ""))

#define RETURN_IF(expr) if (expr) return (char *)fname;

    RETURN_IF(!fname);
    fnlen = strlen(fname);
    if (fnlen >= size) {
        dln_warning(dln_warning_arg
                    "openpath: pathname too long (ignored)\n\tFile \"%.*s\"%s\n",
                    (fnlen > 100 ? 100 : (int)fnlen), fname,
                    (fnlen > 100 ? "..." : ""));
        return NULL;
    }
#ifdef DOSISH
# ifndef CharNext
# define CharNext(p) ((p)+1)
# endif
# ifdef DOSISH_DRIVE_LETTER
    if (((p[0] | 0x20) - 'a') < 26  && p[1] == ':') {
        p += 2;
        is_abs = 1;
    }
# endif
    switch (*p) {
      case '/'case '\\':
        is_abs = 1;
        p++;
    }
    has_path = is_abs;
    while (*p) {
        switch (*p) {
          case '/'case '\\':
            has_path = 1;
            ext = 0;
            p++;
            break;
          case '.':
            ext = p;
            p++;
            break;
          default:
            p = CharNext(p);
        }
    }
    if (ext) {
        for (j = 0; STRCASECMP(ext, extension[j]); ) {
            if (++j == sizeof(extension) / sizeof(extension[0])) {
                ext = 0;
                break;
            }
        }
    }
    ep = bp = 0;
    if (!exe_flag) {
        RETURN_IF(is_abs);
    }
    else if (has_path) {
        RETURN_IF(ext);
        i = p - fname;
        if (i + 1 > size) goto toolong;
        fspace = size - i - 1;
        bp = fbuf;
        ep = p;
        memcpy(fbuf, fname, i + 1);
        goto needs_extension;
    }
    p = fname;
#endif

    if (*p == '.' && *++p == '.') ++p;
    RETURN_IF(*p == '/');
    RETURN_IF(exe_flag && strchr(fname, '/'));

#undef RETURN_IF

    for (dp = path;; dp = ++ep) {
        register size_t l;

        /* extract a component */
        ep = strchr(dp, PATH_SEP[0]);
        if (ep == NULL)
            ep = dp+strlen(dp);

        /* find the length of that component */
        l = ep - dp;
        bp = fbuf;
        fspace = size - 2;
        if (l > 0) {
            /*
            **  If the length of the component is zero length,
            **  start from the current directory.  If the
            **  component begins with "~", start from the
            **  user's $HOME environment variable.  Otherwise
            **  take the path literally.
            */

            if (*dp == '~' && (l == 1 ||
#if defined(DOSISH)
                               dp[1] == '\\' ||
#endif
                               dp[1] == '/')) {
                char *home;

                home = getenv("HOME");
                if (home != NULL) {
                    i = strlen(home);
                    if (fspace < i)
                        goto toolong;
                    fspace -= i;
                    memcpy(bp, home, i);
                    bp += i;
                }
                dp++;
                l--;
            }
            if (l > 0) {
                if (fspace < l)
                    goto toolong;
                fspace -= l;
                memcpy(bp, dp, l);
                bp += l;
            }

            /* add a "/" between directory and filename */
            if (ep[-1] != '/')
                *bp++ = '/';
        }

        /* now append the file name */
        i = fnlen;
        if (fspace < i) {
          toolong:
            PATHNAME_TOO_LONG();
            goto next;
        }
        fspace -= i;
        memcpy(bp, fname, i + 1);

#if defined(DOSISH)
        if (exe_flag && !ext) {
          needs_extension:
            for (j = 0; j < sizeof(extension) / sizeof(extension[0]); j++) {
                if (fspace < strlen(extension[j])) {
                    PATHNAME_TOO_LONG();
                    continue;
                }
                strlcpy(bp + i, extension[j], fspace);
                if (stat(fbuf, &st) == 0)
                    return fbuf;
            }
            goto next;
        }
#endif /* _WIN32 or __EMX__ */

        if (stat(fbuf, &st) == 0) {
            if (exe_flag == 0return fbuf;
            /* looking for executable */
            if (!S_ISDIR(st.st_mode) && eaccess(fbuf, X_OK) == 0)
                return fbuf;
        }
      next:
        /* if not, and no other alternatives, life is bleak */
        if (*ep == '\0') {
            return NULL;
        }

        /* otherwise try the next component in the search path */
    }
}