entry.c

   1 #include "cache.h"
   2 #include "blob.h"
   3
   4 static void create_directories(const char *path, const struct checkout *state)
   5 {
   6         int len = strlen(path);
   7         char *buf = xmalloc(len + 1);
   8         const char *slash = path;
   9
  10         while ((slash = strchr(slash+1, '/')) != NULL) {
  11                 struct stat st;
  12                 int stat_status;
  13
  14                 len = slash - path;
  15                 memcpy(buf, path, len);
  16                 buf[len] = 0;
  17
  18                 if (len <= state->base_dir_len)
  19                         /*
  20                          * checkout-index --prefix=<dir>; <dir> is
  21                          * allowed to be a symlink to an existing
  22                          * directory.
  23                          */
  24                         stat_status = stat(buf, &st);
  25                 else
  26                         /*
  27                          * if there currently is a symlink, we would
  28                          * want to replace it with a real directory.
  29                          */
  30                         stat_status = lstat(buf, &st);
  31
  32                 if (!stat_status && S_ISDIR(st.st_mode))
  33                         continue; /* ok, it is already a directory. */
  34
  35                 /*
  36                  * We know stat_status == 0 means something exists
  37                  * there and this mkdir would fail, but that is an
  38                  * error codepath; we do not care, as we unlink and
  39                  * mkdir again in such a case.
  40                  */
  41                 if (mkdir(buf, 0777)) {
  42                         if (errno == EEXIST && state->force &&
  43                             !unlink(buf) && !mkdir(buf, 0777))
  44                                 continue;
  45                         die("cannot create directory at %s", buf);
  46                 }
  47         }
  48         free(buf);
  49 }
  50
  51 static void remove_subtree(const char *path)
  52 {
  53         DIR *dir = opendir(path);
  54         struct dirent *de;
  55         char pathbuf[PATH_MAX];
  56         char *name;
  57
  58         if (!dir)
  59                 die("cannot opendir %s (%s)", path, strerror(errno));
  60         strcpy(pathbuf, path);
  61         name = pathbuf + strlen(path);
  62         *name++ = '/';
  63         while ((de = readdir(dir)) != NULL) {
  64                 struct stat st;
  65                 if ((de->d_name[0] == '.') &&
  66                     ((de->d_name[1] == 0) ||
  67                      ((de->d_name[1] == '.') && de->d_name[2] == 0)))
  68                         continue;
  69                 strcpy(name, de->d_name);
  70                 if (lstat(pathbuf, &st))
  71                         die("cannot lstat %s (%s)", pathbuf, strerror(errno));
  72                 if (S_ISDIR(st.st_mode))
  73                         remove_subtree(pathbuf);
  74                 else if (unlink(pathbuf))
  75                         die("cannot unlink %s (%s)", pathbuf, strerror(errno));
  76         }
  77         closedir(dir);
  78         if (rmdir(path))
  79                 die("cannot rmdir %s (%s)", path, strerror(errno));
  80 }
  81
  82 static int create_file(const char *path, unsigned int mode)
  83 {
  84         mode = (mode & 0100) ? 0777 : 0666;
  85         return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
  86 }
  87
  88 static void *read_blob_entry(struct cache_entry *ce, const char *path, unsigned long *size)
  89 {
  90         enum object_type type;
  91         void *new = read_sha1_file(ce->sha1, &type, size);
  92
  93         if (new) {
  94                 if (type == OBJ_BLOB)
  95                         return new;
  96                 free(new);
  97         }
  98         return NULL;
  99 }
 100
 101 static int write_entry(struct cache_entry *ce, char *path, const struct checkout *state, int to_tempfile)
 102 {
 103         int fd;
 104         long wrote;
 105
 106         switch (ntohl(ce->ce_mode) & S_IFMT) {
 107                 char *new;
 108                 struct strbuf buf;
 109                 unsigned long size;
 110
 111         case S_IFREG:
 112                 new = read_blob_entry(ce, path, &size);
 113                 if (!new)
 114                         return error("git-checkout-index: unable to read sha1 file of %s (%s)",
 115                                 path, sha1_to_hex(ce->sha1));
 116
 117                 /*
 118                  * Convert from git internal format to working tree format
 119                  */
 120                 strbuf_init(&buf, 0);
 121                 if (convert_to_working_tree(ce->name, new, size, &buf)) {
 122                         free(new);
 123                         new = strbuf_detach(&buf, &size);
 124                 }
 125
 126                 if (to_tempfile) {
 127                         strcpy(path, ".merge_file_XXXXXX");
 128                         fd = mkstemp(path);
 129                 } else
 130                         fd = create_file(path, ntohl(ce->ce_mode));
 131                 if (fd < 0) {
 132                         free(new);
 133                         return error("git-checkout-index: unable to create file %s (%s)",
 134                                 path, strerror(errno));
 135                 }
 136
 137                 wrote = write_in_full(fd, new, size);
 138                 close(fd);
 139                 free(new);
 140                 if (wrote != size)
 141                         return error("git-checkout-index: unable to write file %s", path);
 142                 break;
 143         case S_IFLNK:
 144                 new = read_blob_entry(ce, path, &size);
 145                 if (!new)
 146                         return error("git-checkout-index: unable to read sha1 file of %s (%s)",
 147                                 path, sha1_to_hex(ce->sha1));
 148                 if (to_tempfile || !has_symlinks) {
 149                         if (to_tempfile) {
 150                                 strcpy(path, ".merge_link_XXXXXX");
 151                                 fd = mkstemp(path);
 152                         } else
 153                                 fd = create_file(path, 0666);
 154                         if (fd < 0) {
 155                                 free(new);
 156                                 return error("git-checkout-index: unable to create "
 157                                                  "file %s (%s)", path, strerror(errno));
 158                         }
 159                         wrote = write_in_full(fd, new, size);
 160                         close(fd);
 161                         free(new);
 162                         if (wrote != size)
 163                                 return error("git-checkout-index: unable to write file %s",
 164                                         path);
 165                 } else {
 166                         wrote = symlink(new, path);
 167                         free(new);
 168                         if (wrote)
 169                                 return error("git-checkout-index: unable to create "
 170                                                  "symlink %s (%s)", path, strerror(errno));
 171                 }
 172                 break;
 173         case S_IFGITLINK:
 174                 if (to_tempfile)
 175                         return error("git-checkout-index: cannot create temporary subproject %s", path);
 176                 if (mkdir(path, 0777) < 0)
 177                         return error("git-checkout-index: cannot create subproject directory %s", path);
 178                 break;
 179         default:
 180                 return error("git-checkout-index: unknown file mode for %s", path);
 181         }
 182
 183         if (state->refresh_cache) {
 184                 struct stat st;
 185                 lstat(ce->name, &st);
 186                 fill_stat_cache_info(ce, &st);
 187         }
 188         return 0;
 189 }
 190
 191 int checkout_entry(struct cache_entry *ce, const struct checkout *state, char *topath)
 192 {
 193         static char path[PATH_MAX + 1];
 194         struct stat st;
 195         int len = state->base_dir_len;
 196
 197         if (topath)
 198                 return write_entry(ce, topath, state, 1);
 199
 200         memcpy(path, state->base_dir, len);
 201         strcpy(path + len, ce->name);
 202
 203         if (!lstat(path, &st)) {
 204                 unsigned changed = ce_match_stat(ce, &st, 1);
 205                 if (!changed)
 206                         return 0;
 207                 if (!state->force) {
 208                         if (!state->quiet)
 209                                 fprintf(stderr, "git-checkout-index: %s already exists\n", path);
 210                         return -1;
 211                 }
 212
 213                 /*
 214                  * We unlink the old file, to get the new one with the
 215                  * right permissions (including umask, which is nasty
 216                  * to emulate by hand - much easier to let the system
 217                  * just do the right thing)
 218                  */
 219                 unlink(path);
 220                 if (S_ISDIR(st.st_mode)) {
 221                         /* If it is a gitlink, leave it alone! */
 222                         if (S_ISGITLINK(ntohl(ce->ce_mode)))
 223                                 return 0;
 224                         if (!state->force)
 225                                 return error("%s is a directory", path);
 226                         remove_subtree(path);
 227                 }
 228         } else if (state->not_new)
 229                 return 0;
 230         create_directories(path, state);
 231         return write_entry(ce, path, state, 0);
 232 }