read-tree.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  */
   6 #include "cache.h"
   7
   8 static int read_one_entry(unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode)
   9 {
  10         int len = strlen(pathname);
  11         unsigned int size = cache_entry_size(baselen + len);
  12         struct cache_entry *ce = malloc(size);
  13
  14         memset(ce, 0, size);
  15
  16         ce->st_mode = mode;
  17         ce->namelen = baselen + len;
  18         memcpy(ce->name, base, baselen);
  19         memcpy(ce->name + baselen, pathname, len+1);
  20         memcpy(ce->sha1, sha1, 20);
  21         return add_cache_entry(ce);
  22 }
  23
  24 static int read_tree(unsigned char *sha1, const char *base, int baselen)
  25 {
  26         void *buffer;
  27         unsigned long size;
  28         char type[20];
  29
  30         buffer = read_sha1_file(sha1, type, &size);
  31         if (!buffer)
  32                 return -1;
  33         if (strcmp(type, "tree"))
  34                 return -1;
  35         while (size) {
  36                 int len = strlen(buffer)+1;
  37                 unsigned char *sha1 = buffer + len;
  38                 char *path = strchr(buffer, ' ')+1;
  39                 unsigned int mode;
  40
  41                 if (size < len + 20 || sscanf(buffer, "%o", &mode) != 1)
  42                         return -1;
  43
  44                 buffer = sha1 + 20;
  45                 size -= len + 20;
  46
  47                 if (S_ISDIR(mode)) {
  48                         int retval;
  49                         int pathlen = strlen(path);
  50                         char *newbase = malloc(baselen + 1 + pathlen);
  51                         memcpy(newbase, base, baselen);
  52                         memcpy(newbase + baselen, path, pathlen);
  53                         newbase[baselen + pathlen] = '/';
  54                         retval = read_tree(sha1, newbase, baselen + pathlen + 1);
  55                         free(newbase);
  56                         if (retval)
  57                                 return -1;
  58                         continue;
  59                 }
  60                 if (read_one_entry(sha1, base, baselen, path, mode) < 0)
  61                         return -1;
  62         }
  63         return 0;
  64 }
  65
  66 int main(int argc, char **argv)
  67 {
  68         int i, newfd;
  69         unsigned char sha1[20];
  70
  71         newfd = open(".dircache/index.lock", O_RDWR | O_CREAT | O_EXCL, 0600);
  72         if (newfd < 0)
  73                 usage("unable to create new cachefile");
  74
  75         for (i = 1; i < argc; i++) {
  76                 const char *arg = argv[i];
  77
  78                 /* "-m" stands for "merge" current directory cache */
  79                 if (!strcmp(arg, "-m")) {
  80                         if (active_cache) {
  81                                 fprintf(stderr, "read-tree: cannot merge old cache on top of new\n");
  82                                 goto out;
  83                         }
  84                         if (read_cache() < 0) {
  85                                 fprintf(stderr, "read-tree: corrupt directory cache\n");
  86                                 goto out;
  87                         }
  88                         continue;
  89                 }
  90                 if (get_sha1_hex(arg, sha1) < 0) {
  91                         fprintf(stderr, "read-tree [-m] <sha1>\n");
  92                         goto out;
  93                 }
  94                 if (read_tree(sha1, "", 0) < 0) {
  95                         fprintf(stderr, "failed to unpack tree object %s\n", arg);
  96                         goto out;
  97                 }
  98         }
  99         if (!write_cache(newfd, active_cache, active_nr) && !rename(".dircache/index.lock", ".dircache/index"))
 100                 return 0;
 101
 102 out:
 103         unlink(".dircache/index.lock");
 104         exit(1);
 105 }