git.oblomov.eu Git - git/blob - 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_or_warn(buf) && !mkdir(buf, 0777))
  39                                 continue;
  40                         die_errno("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_errno("cannot opendir '%s'", path);
  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_errno("cannot lstat '%s'", pathbuf);
  65                 if (S_ISDIR(st.st_mode))
  66                         remove_subtree(pathbuf);
  67                 else if (unlink(pathbuf))
  68                         die_errno("cannot unlink '%s'", pathbuf);
  69         }
  70         closedir(dir);
  71         if (rmdir(path))
  72                 die_errno("cannot rmdir '%s'", path);
  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, 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 open_output_fd(char *path, struct cache_entry *ce, int to_tempfile)
  95 {
  96         int symlink = (ce->ce_mode & S_IFMT) != S_IFREG;
  97         if (to_tempfile) {
  98                 strcpy(path, symlink
  99                        ? ".merge_link_XXXXXX" : ".merge_file_XXXXXX");
 100                 return mkstemp(path);
 101         } else {
 102                 return create_file(path, !symlink ? ce->ce_mode : 0666);
 103         }
 104 }
 105
 106 static int fstat_output(int fd, const struct checkout *state, struct stat *st)
 107 {
 108         /* use fstat() only when path == ce->name */
 109         if (fstat_is_reliable() &&
 110             state->refresh_cache && !state->base_dir_len) {
 111                 fstat(fd, st);
 112                 return 1;
 113         }
 114         return 0;
 115 }
 116
 117 static int write_entry(struct cache_entry *ce, char *path, const struct checkout *state, int to_tempfile)
 118 {
 119         unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
 120         int fd, ret, fstat_done = 0;
 121         char *new;
 122         struct strbuf buf = STRBUF_INIT;
 123         unsigned long size;
 124         size_t wrote, newsize = 0;
 125         struct stat st;
 126
 127         switch (ce_mode_s_ifmt) {
 128         case S_IFREG:
 129         case S_IFLNK:
 130                 new = read_blob_entry(ce, &size);
 131                 if (!new)
 132                         return error("unable to read sha1 file of %s (%s)",
 133                                 path, sha1_to_hex(ce->sha1));
 134
 135                 if (ce_mode_s_ifmt == S_IFLNK && has_symlinks && !to_tempfile) {
 136                         ret = symlink(new, path);
 137                         free(new);
 138                         if (ret)
 139                                 return error("unable to create symlink %s (%s)",
 140                                              path, strerror(errno));
 141                         break;
 142                 }
 143
 144                 /*
 145                  * Convert from git internal format to working tree format
 146                  */
 147                 if (ce_mode_s_ifmt == S_IFREG &&
 148                     convert_to_working_tree(ce->name, new, size, &buf)) {
 149                         free(new);
 150                         new = strbuf_detach(&buf, &newsize);
 151                         size = newsize;
 152                 }
 153
 154                 fd = open_output_fd(path, ce, to_tempfile);
 155                 if (fd < 0) {
 156                         free(new);
 157                         return error("unable to create file %s (%s)",
 158                                 path, strerror(errno));
 159                 }
 160
 161                 wrote = write_in_full(fd, new, size);
 162                 if (!to_tempfile)
 163                         fstat_done = fstat_output(fd, state, &st);
 164                 close(fd);
 165                 free(new);
 166                 if (wrote != size)
 167                         return error("unable to write file %s", path);
 168                 break;
 169         case S_IFGITLINK:
 170                 if (to_tempfile)
 171                         return error("cannot create temporary subproject %s", path);
 172                 if (mkdir(path, 0777) < 0)
 173                         return error("cannot create subproject directory %s", path);
 174                 break;
 175         default:
 176                 return error("unknown file mode for %s in index", path);
 177         }
 178
 179         if (state->refresh_cache) {
 180                 if (!fstat_done)
 181                         lstat(ce->name, &st);
 182                 fill_stat_cache_info(ce, &st);
 183         }
 184         return 0;
 185 }
 186
 187 /*
 188  * This is like 'lstat()', except it refuses to follow symlinks
 189  * in the path, after skipping "skiplen".
 190  */
 191 static int check_path(const char *path, int len, struct stat *st, int skiplen)
 192 {
 193         const char *slash = path + len;
 194
 195         while (path < slash && *slash != '/')
 196                 slash--;
 197         if (!has_dirs_only_path(path, slash - path, skiplen)) {
 198                 errno = ENOENT;
 199                 return -1;
 200         }
 201         return lstat(path, st);
 202 }
 203
 204 int checkout_entry(struct cache_entry *ce, const struct checkout *state, char *topath)
 205 {
 206         static char path[PATH_MAX + 1];
 207         struct stat st;
 208         int len = state->base_dir_len;
 209
 210         if (topath)
 211                 return write_entry(ce, topath, state, 1);
 212
 213         memcpy(path, state->base_dir, len);
 214         strcpy(path + len, ce->name);
 215         len += ce_namelen(ce);
 216
 217         if (!check_path(path, len, &st, state->base_dir_len)) {
 218                 unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
 219                 if (!changed)
 220                         return 0;
 221                 if (!state->force) {
 222                         if (!state->quiet)
 223                                 fprintf(stderr, "%s already exists, no checkout\n", path);
 224                         return -1;
 225                 }
 226
 227                 /*
 228                  * We unlink the old file, to get the new one with the
 229                  * right permissions (including umask, which is nasty
 230                  * to emulate by hand - much easier to let the system
 231                  * just do the right thing)
 232                  */
 233                 if (S_ISDIR(st.st_mode)) {
 234                         /* If it is a gitlink, leave it alone! */
 235                         if (S_ISGITLINK(ce->ce_mode))
 236                                 return 0;
 237                         if (!state->force)
 238                                 return error("%s is a directory", path);
 239                         remove_subtree(path);
 240                 } else if (unlink(path))
 241                         return error("unable to unlink old '%s' (%s)", path, strerror(errno));
 242         } else if (state->not_new)
 243                 return 0;
 244         create_directories(path, len, state);
 245         return write_entry(ce, path, state, 0);
 246 }