entry.c

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