entry.c

   1 #include <sys/types.h>
   2 #include <dirent.h>
   3 #include "cache.h"
   4
   5 static void create_directories(const char *path, struct checkout *state)
   6 {
   7         int len = strlen(path);
   8         char *buf = xmalloc(len + 1);
   9         const char *slash = path;
  10
  11         while ((slash = strchr(slash+1, '/')) != NULL) {
  12                 len = slash - path;
  13                 memcpy(buf, path, len);
  14                 buf[len] = 0;
  15                 if (mkdir(buf, 0777)) {
  16                         if (errno == EEXIST) {
  17                                 struct stat st;
  18                                 if (len > state->base_dir_len && state->force && !unlink(buf) && !mkdir(buf, 0777))
  19                                         continue;
  20                                 if (!stat(buf, &st) && S_ISDIR(st.st_mode))
  21                                         continue; /* ok */
  22                         }
  23                         die("cannot create directory at %s", buf);
  24                 }
  25         }
  26         free(buf);
  27 }
  28
  29 static void remove_subtree(const char *path)
  30 {
  31         DIR *dir = opendir(path);
  32         struct dirent *de;
  33         char pathbuf[PATH_MAX];
  34         char *name;
  35
  36         if (!dir)
  37                 die("cannot opendir %s", path);
  38         strcpy(pathbuf, path);
  39         name = pathbuf + strlen(path);
  40         *name++ = '/';
  41         while ((de = readdir(dir)) != NULL) {
  42                 struct stat st;
  43                 if ((de->d_name[0] == '.') &&
  44                     ((de->d_name[1] == 0) ||
  45                      ((de->d_name[1] == '.') && de->d_name[2] == 0)))
  46                         continue;
  47                 strcpy(name, de->d_name);
  48                 if (lstat(pathbuf, &st))
  49                         die("cannot lstat %s", pathbuf);
  50                 if (S_ISDIR(st.st_mode))
  51                         remove_subtree(pathbuf);
  52                 else if (unlink(pathbuf))
  53                         die("cannot unlink %s", pathbuf);
  54         }
  55         closedir(dir);
  56         if (rmdir(path))
  57                 die("cannot rmdir %s", path);
  58 }
  59
  60 static int create_file(const char *path, unsigned int mode, int force)
  61 {
  62         int fd;
  63
  64         mode = (mode & 0100) ? 0777 : 0666;
  65         fd = open(path, O_WRONLY | O_TRUNC | O_CREAT | O_EXCL, mode);
  66         if (fd < 0) {
  67                 if (errno == EISDIR && force) {
  68                         remove_subtree(path);
  69                         fd = open(path, O_WRONLY | O_TRUNC | O_CREAT | O_EXCL, mode);
  70                 }
  71         }
  72         return fd;
  73 }
  74
  75 static int write_entry(struct cache_entry *ce, const char *path, struct checkout *state)
  76 {
  77         int fd;
  78         void *new;
  79         unsigned long size;
  80         long wrote;
  81         char type[20];
  82         char target[1024];
  83
  84         new = read_sha1_file(ce->sha1, type, &size);
  85         if (!new || strcmp(type, "blob")) {
  86                 if (new)
  87                         free(new);
  88                 return error("git-checkout-cache: unable to read sha1 file of %s (%s)",
  89                         path, sha1_to_hex(ce->sha1));
  90         }
  91         switch (ntohl(ce->ce_mode) & S_IFMT) {
  92         case S_IFREG:
  93                 fd = create_file(path, ntohl(ce->ce_mode), state->force);
  94                 if (fd < 0) {
  95                         free(new);
  96                         return error("git-checkout-cache: unable to create file %s (%s)",
  97                                 path, strerror(errno));
  98                 }
  99                 wrote = write(fd, new, size);
 100                 close(fd);
 101                 free(new);
 102                 if (wrote != size)
 103                         return error("git-checkout-cache: unable to write file %s", path);
 104                 break;
 105         case S_IFLNK:
 106                 memcpy(target, new, size);
 107                 target[size] = '\0';
 108                 if (symlink(target, path)) {
 109                         free(new);
 110                         return error("git-checkout-cache: unable to create symlink %s (%s)",
 111                                 path, strerror(errno));
 112                 }
 113                 free(new);
 114                 break;
 115         default:
 116                 free(new);
 117                 return error("git-checkout-cache: unknown file mode for %s", path);
 118         }
 119
 120         if (state->refresh_cache) {
 121                 struct stat st;
 122                 lstat(ce->name, &st);
 123                 fill_stat_cache_info(ce, &st);
 124         }
 125         return 0;
 126 }
 127
 128 int checkout_entry(struct cache_entry *ce, struct checkout *state)
 129 {
 130         struct stat st;
 131         static char path[MAXPATHLEN+1];
 132         int len = state->base_dir_len;
 133
 134         memcpy(path, state->base_dir, len);
 135         strcpy(path + len, ce->name);
 136
 137         if (!lstat(path, &st)) {
 138                 unsigned changed = ce_match_stat(ce, &st);
 139                 if (!changed)
 140                         return 0;
 141                 if (!state->force) {
 142                         if (!state->quiet)
 143                                 fprintf(stderr, "git-checkout-cache: %s already exists\n", path);
 144                         return 0;
 145                 }
 146
 147                 /*
 148                  * We unlink the old file, to get the new one with the
 149                  * right permissions (including umask, which is nasty
 150                  * to emulate by hand - much easier to let the system
 151                  * just do the right thing)
 152                  */
 153                 unlink(path);
 154         } else if (state->not_new)
 155                 return 0;
 156         create_directories(path, state);
 157         return write_entry(ce, path, state);
 158 }
 159
 160