minix/tests/test43.c

   1 /* Tests for MINIX3 realpath(3) - by Erik van der Kouwe */
   2 #include <assert.h>
   3 #include <dirent.h>
   4 #include <errno.h>
   5 #include <libgen.h>
   6 #include <limits.h>
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10 #include <sys/stat.h>
  11 #include <unistd.h>
  12
  13 int max_error = 3;
  14 #include "common.h"
  15
  16
  17 int subtest;
  18 static const char *executable;
  19
  20
  21 #define ERR (e(__LINE__))
  22
  23 static char *remove_last_path_component(char *path)
  24 {
  25         char *current, *last;
  26
  27         assert(path);
  28
  29         /* find last slash */
  30         last = NULL;
  31         for (current = path; *current; current++)
  32                 if (*current == '/')
  33                         last = current;
  34
  35         /* check path component */
  36         if (last)
  37         {
  38                 if (strcmp(last + 1, ".") == 0) ERR;
  39                 if (strcmp(last + 1, "..") == 0) ERR;
  40         }
  41
  42         /* if only root path slash, we are done */
  43         if (last <= path)
  44                 return NULL;
  45
  46         /* chop off last path component */
  47         *last = 0;
  48         return path;
  49 }
  50
  51 static int check_path_components(const char *path)
  52 {
  53         char buffer[PATH_MAX + 1], *bufferpos;
  54         struct stat statbuf;
  55
  56         assert(strlen(path) < sizeof(buffer));
  57
  58         bufferpos = buffer;
  59         while (*path)
  60         {
  61                 /* copy next path segment */
  62                 do
  63                 {
  64                         *(bufferpos++) = *(path++);
  65                 } while (*path && *path != '/');
  66                 *bufferpos = 0;
  67
  68                 /*
  69                  * is this a valid path segment? if not, return errno.
  70                  * one exception: the last path component need not exist
  71                  * - unless it is actually a dangling symlink
  72                  */
  73                 if (stat(buffer, &statbuf) < 0 &&
  74                         (*path || errno != ENOENT ||
  75                         lstat(buffer, &statbuf) == 0))
  76                         return errno;
  77         }
  78
  79         return 0;
  80 }
  81
  82 static void check_realpath(const char *path, int expected_errno)
  83 {
  84         char buffer[PATH_MAX + 1], *resolved_path;
  85         int expected_errno2;
  86         struct stat statbuf[2];
  87
  88         assert(path);
  89
  90         /* any errors in the path that realpath should report? */
  91         expected_errno2 = check_path_components(path);
  92
  93         /* run realpath */
  94         errno = 0;
  95         resolved_path = realpath(path, buffer);
  96
  97         /* do we get errors when expected? */
  98         if (expected_errno || expected_errno2)
  99         {
 100                 if (resolved_path) ERR;
 101                 if (errno != expected_errno && errno != expected_errno2) ERR;
 102                 return;
 103         }
 104
 105         /* do we get success when expected? */
 106         if (!resolved_path)
 107         {
 108                 ERR;
 109                 return;
 110         }
 111         errno = 0;
 112
 113         /* do the paths point to the same file? (only check if exists) */
 114         if (stat(path,          &statbuf[0]) < 0)
 115         {
 116                 if (errno != ENOENT) { ERR; return; }
 117         }
 118         else
 119         {
 120                 if (stat(resolved_path, &statbuf[1]) < 0) { ERR; return; }
 121                 if (statbuf[0].st_dev != statbuf[1].st_dev) ERR;
 122                 if (statbuf[0].st_ino != statbuf[1].st_ino) ERR;
 123         }
 124
 125         /* is the path absolute? */
 126         if (resolved_path[0] != '/') ERR;
 127
 128         /* is each path element allowable? */
 129         while (remove_last_path_component(resolved_path))
 130         {
 131                 /* not a symlink? */
 132                 if (lstat(resolved_path, &statbuf[1]) < 0) { ERR; return; }
 133                 if ((statbuf[1].st_mode & S_IFMT) != S_IFDIR) ERR;
 134         }
 135 }
 136
 137 static void check_realpath_step_by_step(const char *path, int expected_errno)
 138 {
 139         char buffer[PATH_MAX + 1];
 140         const char *path_current;
 141
 142         assert(path);
 143         assert(strlen(path) < sizeof(buffer));
 144
 145         /* check the absolute path */
 146         check_realpath(path, expected_errno);
 147
 148         /* try with different CWDs */
 149         for (path_current = path; *path_current; path_current++)
 150                 if (path_current[0] == '/' && path_current[1])
 151                 {
 152                         /* set CWD */
 153                         memcpy(buffer, path, path_current - path + 1);
 154                         buffer[path_current - path + 1] = 0;
 155                         if (chdir(buffer) < 0) { ERR; continue; }
 156
 157                         /* perform test */
 158                         check_realpath(path_current + 1, expected_errno);
 159                 }
 160 }
 161
 162 static char *pathncat(char *buffer, size_t size, const char *path1, const char *path2)
 163 {
 164         size_t len1, len2, lenslash;
 165
 166         assert(buffer);
 167         assert(path1);
 168         assert(path2);
 169
 170         /* check whether it fits */
 171         len1 = strlen(path1);
 172         len2 = strlen(path2);
 173         lenslash = (len1 > 0 && path1[len1 - 1] == '/') ? 0 : 1;
 174         if (len1 >= size || /* check individual components to avoid overflow */
 175                 len2 >= size ||
 176                 len1 + len2 + lenslash >= size)
 177                 return NULL;
 178
 179         /* perform the copy */
 180         memcpy(buffer, path1, len1);
 181         if (lenslash)
 182                 buffer[len1] = '/';
 183
 184         memcpy(buffer + len1 + lenslash, path2, len2 + 1);
 185         return buffer;
 186 }
 187
 188 static void check_realpath_recurse(const char *path, int depth)
 189 {
 190         DIR *dir;
 191         struct dirent *dirent;
 192         char pathsub[PATH_MAX + 1];
 193         struct stat st;
 194
 195         /* check with the path itself */
 196         check_realpath_step_by_step(path, 0);
 197
 198         /* don't go too deep */
 199         if (depth < 1)
 200                 return;
 201
 202         /* don't bother with non-directories. Due to timeouts in drivers we
 203          * might not get expected results and takes way too long */
 204         if (stat(path, &st) != 0) {
 205                 /* dangling symlinks may cause legitimate failures here */
 206                 if (lstat(path, &st) != 0) ERR;
 207                 return;
 208         }
 209         if (!S_ISDIR(st.st_mode))
 210                 return;
 211
 212         /* loop through subdirectories (including . and ..) */
 213         if (!(dir = opendir(path)))
 214         {
 215                 /* Opening some special files might result in errors when the
 216                  * corresponding hardware is not present, or simply when access
 217                  * rights prohibit access (e.g., /dev/log).
 218                  */
 219                 if (errno != ENOTDIR
 220                     && errno != ENXIO && errno != EIO && errno != EACCES) {
 221                         ERR;
 222                 }
 223                 return;
 224         }
 225         while ((dirent = readdir(dir)) != NULL)
 226         {
 227                 /* build path */
 228                 if (!pathncat(pathsub, sizeof(pathsub), path, dirent->d_name))
 229                 {
 230                         ERR;
 231                         continue;
 232                 }
 233
 234                 /* check path */
 235                 check_realpath_recurse(pathsub, depth - 1);
 236         }
 237         if (closedir(dir) < 0) ERR;
 238 }
 239
 240 #define PATH_DEPTH 4
 241 #define PATH_BASE "/."
 242 #define L(x) PATH_BASE "/link_" #x ".tmp"
 243
 244 static char basepath[PATH_MAX + 1];
 245
 246 static char *addbasepath(char *buffer, const char *path)
 247 {
 248         size_t basepathlen, pathlen;
 249
 250         /* assumption: both start with slash and neither end with it */
 251         assert(basepath[0] == '/');
 252         assert(basepath[strlen(basepath) - 1] != '/');
 253         assert(buffer);
 254         assert(path);
 255         assert(path[0] == '/');
 256
 257         /* check result length */
 258         basepathlen = strlen(basepath);
 259         pathlen = strlen(path);
 260         if (basepathlen + pathlen > PATH_MAX)
 261         {
 262                 printf("path too long\n");
 263                 exit(-1);
 264         }
 265
 266         /* concatenate base path and path */
 267         memcpy(buffer, basepath, basepathlen);
 268         memcpy(buffer + basepathlen, path, pathlen + 1);
 269         return buffer;
 270 }
 271
 272 static void test_dirname(const char *path, const char *exp)
 273 {
 274         char buffer[PATH_MAX];
 275         int i, j;
 276         size_t pathlen = strlen(path);
 277         char *pathout;
 278
 279         assert(pathlen + 3 < PATH_MAX);
 280
 281         /* try with no, one or two trailing slashes */
 282         for (i = 0; i < 3; i++)
 283         {
 284                 /* no trailing slashes for empty string */
 285                 if (pathlen < 1 && i > 0)
 286                         continue;
 287
 288                 /* prepare buffer */
 289                 strcpy(buffer, path);
 290                 for (j = 0; j < i; j++)
 291                         buffer[pathlen + j] = '/';
 292
 293                 buffer[pathlen + i] = 0;
 294
 295                 /* perform test */
 296                 pathout = dirname(buffer);
 297                 if (strcmp(pathout, exp) != 0)
 298                         ERR;
 299         }
 300 }
 301
 302 int main(int argc, char **argv)
 303 {
 304         char buffer1[PATH_MAX + 1], buffer2[PATH_MAX + 1];
 305         subtest = 1;
 306
 307         /* initialize */
 308         start(43);
 309         executable = argv[0];
 310         getcwd(basepath, sizeof(basepath));
 311
 312         /* prepare some symlinks to make it more difficult */
 313         if (symlink("/",      addbasepath(buffer1, L(1))) < 0) ERR;
 314         if (symlink(basepath, addbasepath(buffer1, L(2))) < 0) ERR;
 315
 316         /* perform some tests */
 317         check_realpath_recurse(basepath, PATH_DEPTH);
 318
 319         /* now try with recursive symlinks */
 320         if (symlink(addbasepath(buffer1, L(3)), addbasepath(buffer2, L(3))) < 0) ERR;
 321         if (symlink(addbasepath(buffer1, L(5)), addbasepath(buffer2, L(4))) < 0) ERR;
 322         if (symlink(addbasepath(buffer1, L(4)), addbasepath(buffer2, L(5))) < 0) ERR;
 323         check_realpath_step_by_step(addbasepath(buffer1, L(3)), ELOOP);
 324         check_realpath_step_by_step(addbasepath(buffer1, L(4)), ELOOP);
 325         check_realpath_step_by_step(addbasepath(buffer1, L(5)), ELOOP);
 326
 327         /* delete the symlinks */
 328         cleanup();
 329
 330         /* also test dirname */
 331         test_dirname("", ".");
 332         test_dirname(".", ".");
 333         test_dirname("..", ".");
 334         test_dirname("x", ".");
 335         test_dirname("xy", ".");
 336         test_dirname("x/y", "x");
 337         test_dirname("xy/z", "xy");
 338         test_dirname("x/yz", "x");
 339         test_dirname("ab/cd", "ab");
 340         test_dirname("x//y", "x");
 341         test_dirname("xy//z", "xy");
 342         test_dirname("x//yz", "x");
 343         test_dirname("ab//cd", "ab");
 344         test_dirname("/", "/");
 345         test_dirname("/x", "/");
 346         test_dirname("/xy", "/");
 347         test_dirname("/x/y", "/x");
 348         test_dirname("/xy/z", "/xy");
 349         test_dirname("/x/yz", "/x");
 350         test_dirname("/ab/cd", "/ab");
 351         test_dirname("/x//y", "/x");
 352         test_dirname("/xy//z", "/xy");
 353         test_dirname("/x//yz", "/x");
 354         test_dirname("/ab//cd", "/ab");
 355         test_dirname("/usr/src", "/usr");
 356         test_dirname("/usr/src/test", "/usr/src");
 357         test_dirname("usr/src", "usr");
 358         test_dirname("usr/src/test", "usr/src");
 359
 360         /* done */
 361         quit();
 362         return(-1);     /* impossible */
 363 }