mono/utils/mono-io-portability.c

   1 #include "config.h"
   2
   3 #include <string.h>
   4 #ifdef HAVE_UNISTD_H
   5 #include <unistd.h>
   6 #endif
   7 #include <errno.h>
   8 #include <mono/utils/mono-io-portability.h>
   9
  10 #ifdef DISABLE_PORTABILITY
  11 int __mono_io_portability_helpers = PORTABILITY_NONE;
  12
  13 void
  14 mono_portability_helpers_init (void)
  15 {
  16 }
  17
  18 gchar *
  19 mono_portability_find_file (const gchar *pathname, gboolean last_exists)
  20 {
  21         g_assert_not_reached();
  22         return NULL;
  23 }
  24
  25 #else
  26
  27 #include <dirent.h>
  28
  29 int __mono_io_portability_helpers = PORTABILITY_UNKNOWN;
  30
  31 void mono_portability_helpers_init (void)
  32 {
  33         const gchar *env;
  34
  35         if (__mono_io_portability_helpers != PORTABILITY_UNKNOWN)
  36                 return;
  37
  38         __mono_io_portability_helpers = PORTABILITY_NONE;
  39
  40         env = g_getenv ("MONO_IOMAP");
  41         if (env != NULL) {
  42                 /* parse the environment setting and set up some vars
  43                  * here
  44                  */
  45                 gchar **options = g_strsplit (env, ":", 0);
  46                 int i;
  47
  48                 if (options == NULL) {
  49                         /* This shouldn't happen */
  50                         return;
  51                 }
  52
  53                 for (i = 0; options[i] != NULL; i++) {
  54 #ifdef DEBUG
  55                         g_message ("%s: Setting option [%s]", __func__,
  56                                    options[i]);
  57 #endif
  58                         if (!strncasecmp (options[i], "drive", 5)) {
  59                                 __mono_io_portability_helpers |= PORTABILITY_DRIVE;
  60                         } else if (!strncasecmp (options[i], "case", 4)) {
  61                                 __mono_io_portability_helpers |= PORTABILITY_CASE;
  62                         } else if (!strncasecmp (options[i], "all", 3)) {
  63                                 __mono_io_portability_helpers |= (PORTABILITY_DRIVE |
  64                                                                   PORTABILITY_CASE);
  65                         }
  66                 }
  67         }
  68 }
  69
  70 /* Returns newly allocated string, or NULL on failure */
  71 static gchar *find_in_dir (DIR *current, const gchar *name)
  72 {
  73         struct dirent *entry;
  74
  75 #ifdef DEBUG
  76         g_message ("%s: looking for [%s]\n", __func__, name);
  77 #endif
  78
  79         while((entry = readdir (current)) != NULL) {
  80 #ifdef DEBUGX
  81                 g_message ("%s: found [%s]\n", __func__, entry->d_name);
  82 #endif
  83
  84                 if (!g_ascii_strcasecmp (name, entry->d_name)) {
  85                         char *ret;
  86
  87 #ifdef DEBUG
  88                         g_message ("%s: matched [%s] to [%s]\n", __func__,
  89                                    entry->d_name, name);
  90 #endif
  91
  92                         ret = g_strdup (entry->d_name);
  93                         closedir (current);
  94                         return ret;
  95                 }
  96         }
  97
  98 #ifdef DEBUG
  99         g_message ("%s: returning NULL\n", __func__);
 100 #endif
 101
 102         closedir (current);
 103
 104         return(NULL);
 105 }
 106
 107 /* Returns newly-allocated string or NULL on failure */
 108 gchar *mono_portability_find_file (const gchar *pathname, gboolean last_exists)
 109 {
 110         gchar *new_pathname, **components, **new_components;
 111         int num_components = 0, component = 0;
 112         DIR *scanning = NULL;
 113         size_t len;
 114
 115         if (IS_PORTABILITY_NONE) {
 116                 return(NULL);
 117         }
 118
 119         new_pathname = g_strdup (pathname);
 120
 121 #ifdef DEBUG
 122         g_message ("%s: Finding [%s] last_exists: %s\n", __func__, pathname,
 123                    last_exists?"TRUE":"FALSE");
 124 #endif
 125
 126         if (last_exists &&
 127             access (new_pathname, F_OK) == 0) {
 128 #ifdef DEBUG
 129                 g_message ("%s: Found it without doing anything\n", __func__);
 130 #endif
 131                 return(new_pathname);
 132         }
 133
 134         /* First turn '\' into '/' and strip any drive letters */
 135         g_strdelimit (new_pathname, "\\", '/');
 136
 137 #ifdef DEBUG
 138         g_message ("%s: Fixed slashes, now have [%s]\n", __func__,
 139                    new_pathname);
 140 #endif
 141
 142         if (IS_PORTABILITY_DRIVE &&
 143             g_ascii_isalpha (new_pathname[0]) &&
 144             (new_pathname[1] == ':')) {
 145                 int len = strlen (new_pathname);
 146
 147                 g_memmove (new_pathname, new_pathname+2, len - 2);
 148                 new_pathname[len - 2] = '\0';
 149
 150 #ifdef DEBUG
 151                 g_message ("%s: Stripped drive letter, now looking for [%s]\n",
 152                            __func__, new_pathname);
 153 #endif
 154         }
 155
 156         len = strlen (new_pathname);
 157         if (len > 1 && new_pathname [len - 1] == '/') {
 158                 new_pathname [len - 1] = 0;
 159 #ifdef DEBUG
 160                 g_message ("%s: requested name had a trailing /, rewritten to '%s'\n",
 161                            __func__, new_pathname);
 162 #endif
 163         }
 164
 165         if (last_exists &&
 166             access (new_pathname, F_OK) == 0) {
 167 #ifdef DEBUG
 168                 g_message ("%s: Found it\n", __func__);
 169 #endif
 170
 171                 return(new_pathname);
 172         }
 173
 174         /* OK, have to work harder.  Take each path component in turn
 175          * and do a case-insensitive directory scan for it
 176          */
 177
 178         if (!(IS_PORTABILITY_CASE)) {
 179                 g_free (new_pathname);
 180                 return(NULL);
 181         }
 182
 183         components = g_strsplit (new_pathname, "/", 0);
 184         if (components == NULL) {
 185                 /* This shouldn't happen */
 186                 g_free (new_pathname);
 187                 return(NULL);
 188         }
 189
 190         while(components[num_components] != NULL) {
 191                 num_components++;
 192         }
 193         g_free (new_pathname);
 194
 195         if (num_components == 0){
 196                 return NULL;
 197         }
 198
 199
 200         new_components = (gchar **)g_new0 (gchar **, num_components + 1);
 201
 202         if (num_components > 1) {
 203                 if (strcmp (components[0], "") == 0) {
 204                         /* first component blank, so start at / */
 205                         scanning = opendir ("/");
 206                         if (scanning == NULL) {
 207 #ifdef DEBUG
 208                                 g_message ("%s: opendir 1 error: %s", __func__,
 209                                            g_strerror (errno));
 210 #endif
 211                                 g_strfreev (new_components);
 212                                 g_strfreev (components);
 213                                 return(NULL);
 214                         }
 215
 216                         new_components[component++] = g_strdup ("");
 217                 } else {
 218                         DIR *current;
 219                         gchar *entry;
 220
 221                         current = opendir (".");
 222                         if (current == NULL) {
 223 #ifdef DEBUG
 224                                 g_message ("%s: opendir 2 error: %s", __func__,
 225                                            g_strerror (errno));
 226 #endif
 227                                 g_strfreev (new_components);
 228                                 g_strfreev (components);
 229                                 return(NULL);
 230                         }
 231
 232                         entry = find_in_dir (current, components[0]);
 233                         if (entry == NULL) {
 234                                 g_strfreev (new_components);
 235                                 g_strfreev (components);
 236                                 return(NULL);
 237                         }
 238
 239                         scanning = opendir (entry);
 240                         if (scanning == NULL) {
 241 #ifdef DEBUG
 242                                 g_message ("%s: opendir 3 error: %s", __func__,
 243                                            g_strerror (errno));
 244 #endif
 245                                 g_free (entry);
 246                                 g_strfreev (new_components);
 247                                 g_strfreev (components);
 248                                 return(NULL);
 249                         }
 250
 251                         new_components[component++] = entry;
 252                 }
 253         } else {
 254                 if (last_exists) {
 255                         if (strcmp (components[0], "") == 0) {
 256                                 /* First and only component blank */
 257                                 new_components[component++] = g_strdup ("");
 258                         } else {
 259                                 DIR *current;
 260                                 gchar *entry;
 261
 262                                 current = opendir (".");
 263                                 if (current == NULL) {
 264 #ifdef DEBUG
 265                                         g_message ("%s: opendir 4 error: %s",
 266                                                    __func__,
 267                                                    g_strerror (errno));
 268 #endif
 269                                         g_strfreev (new_components);
 270                                         g_strfreev (components);
 271                                         return(NULL);
 272                                 }
 273
 274                                 entry = find_in_dir (current, components[0]);
 275                                 if (entry == NULL) {
 276                                         g_strfreev (new_components);
 277                                         g_strfreev (components);
 278                                         return(NULL);
 279                                 }
 280
 281                                 new_components[component++] = entry;
 282                         }
 283                 } else {
 284                                 new_components[component++] = g_strdup (components[0]);
 285                 }
 286         }
 287
 288 #ifdef DEBUG
 289         g_message ("%s: Got first entry: [%s]\n", __func__, new_components[0]);
 290 #endif
 291
 292         g_assert (component == 1);
 293
 294         for(; component < num_components; component++) {
 295                 gchar *entry;
 296                 gchar *path_so_far;
 297
 298                 if (!last_exists &&
 299                     component == num_components -1) {
 300                         entry = g_strdup (components[component]);
 301                         closedir (scanning);
 302                 } else {
 303                         entry = find_in_dir (scanning, components[component]);
 304                         if (entry == NULL) {
 305                                 g_strfreev (new_components);
 306                                 g_strfreev (components);
 307                                 return(NULL);
 308                         }
 309                 }
 310
 311                 new_components[component] = entry;
 312
 313                 if (component < num_components -1) {
 314                         path_so_far = g_strjoinv ("/", new_components);
 315
 316                         scanning = opendir (path_so_far);
 317                         g_free (path_so_far);
 318                         if (scanning == NULL) {
 319                                 g_strfreev (new_components);
 320                                 g_strfreev (components);
 321                                 return(NULL);
 322                         }
 323                 }
 324         }
 325
 326         g_strfreev (components);
 327
 328         new_pathname = g_strjoinv ("/", new_components);
 329
 330 #ifdef DEBUG
 331         g_message ("%s: pathname [%s] became [%s]\n", __func__, pathname,
 332                    new_pathname);
 333 #endif
 334
 335         g_strfreev (new_components);
 336
 337         if ((last_exists &&
 338              access (new_pathname, F_OK) == 0) ||
 339             (!last_exists)) {
 340                 return(new_pathname);
 341         }
 342
 343         g_free (new_pathname);
 344         return(NULL);
 345 }
 346
 347
 348 #endif