write-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 missing_ok = 0;
   9
  10 static int check_valid_sha1(unsigned char *sha1)
  11 {
  12         int ret;
  13
  14         /* If we were anal, we'd check that the sha1 of the contents actually matches */
  15         ret = has_sha1_file(sha1);
  16         if (ret == 0)
  17                 perror(sha1_file_name(sha1));
  18         return ret ? 0 : -1;
  19 }
  20
  21 static int write_tree(struct cache_entry **cachep, int maxentries, const char *base, int baselen, unsigned char *returnsha1)
  22 {
  23         unsigned char subdir_sha1[20];
  24         unsigned long size, offset;
  25         char *buffer;
  26         int nr;
  27
  28         /* Guess at some random initial size */
  29         size = 8192;
  30         buffer = xmalloc(size);
  31         offset = 0;
  32
  33         nr = 0;
  34         while (nr < maxentries) {
  35                 struct cache_entry *ce = cachep[nr];
  36                 const char *pathname = ce->name, *filename, *dirname;
  37                 int pathlen = ce_namelen(ce), entrylen;
  38                 unsigned char *sha1;
  39                 unsigned int mode;
  40
  41                 /* Did we hit the end of the directory? Return how many we wrote */
  42                 if (baselen >= pathlen || memcmp(base, pathname, baselen))
  43                         break;
  44
  45                 sha1 = ce->sha1;
  46                 mode = ntohl(ce->ce_mode);
  47
  48                 /* Do we have _further_ subdirectories? */
  49                 filename = pathname + baselen;
  50                 dirname = strchr(filename, '/');
  51                 if (dirname) {
  52                         int subdir_written;
  53
  54                         subdir_written = write_tree(cachep + nr, maxentries - nr, pathname, dirname-pathname+1, subdir_sha1);
  55                         nr += subdir_written;
  56
  57                         /* Now we need to write out the directory entry into this tree.. */
  58                         mode = S_IFDIR;
  59                         pathlen = dirname - pathname;
  60
  61                         /* ..but the directory entry doesn't count towards the total count */
  62                         nr--;
  63                         sha1 = subdir_sha1;
  64                 }
  65
  66                 if (!missing_ok && check_valid_sha1(sha1) < 0)
  67                         exit(1);
  68
  69                 entrylen = pathlen - baselen;
  70                 if (offset + entrylen + 100 > size) {
  71                         size = alloc_nr(offset + entrylen + 100);
  72                         buffer = xrealloc(buffer, size);
  73                 }
  74                 offset += sprintf(buffer + offset, "%o %.*s", mode, entrylen, filename);
  75                 buffer[offset++] = 0;
  76                 memcpy(buffer + offset, sha1, 20);
  77                 offset += 20;
  78                 nr++;
  79         }
  80
  81         write_sha1_file(buffer, offset, "tree", returnsha1);
  82         free(buffer);
  83         return nr;
  84 }
  85
  86 static const char write_tree_usage[] = "git-write-tree [--missing-ok]";
  87
  88 int main(int argc, char **argv)
  89 {
  90         int i, funny;
  91         int entries;
  92         unsigned char sha1[20];
  93
  94         setup_git_directory();
  95
  96         entries = read_cache();
  97         if (argc == 2) {
  98                 if (!strcmp(argv[1], "--missing-ok"))
  99                         missing_ok = 1;
 100                 else
 101                         die(write_tree_usage);
 102         }
 103
 104         if (argc > 2)
 105                 die("too many options");
 106
 107         if (entries < 0)
 108                 die("git-write-tree: error reading cache");
 109
 110         /* Verify that the tree is merged */
 111         funny = 0;
 112         for (i = 0; i < entries; i++) {
 113                 struct cache_entry *ce = active_cache[i];
 114                 if (ntohs(ce->ce_flags) & ~CE_NAMEMASK) {
 115                         if (10 < ++funny) {
 116                                 fprintf(stderr, "...\n");
 117                                 break;
 118                         }
 119                         fprintf(stderr, "%s: unmerged (%s)\n", ce->name, sha1_to_hex(ce->sha1));
 120                 }
 121         }
 122         if (funny)
 123                 die("git-write-tree: not able to write tree");
 124
 125         /* Also verify that the cache does not have path and path/file
 126          * at the same time.  At this point we know the cache has only
 127          * stage 0 entries.
 128          */
 129         funny = 0;
 130         for (i = 0; i < entries - 1; i++) {
 131                 /* path/file always comes after path because of the way
 132                  * the cache is sorted.  Also path can appear only once,
 133                  * which means conflicting one would immediately follow.
 134                  */
 135                 const char *this_name = active_cache[i]->name;
 136                 const char *next_name = active_cache[i+1]->name;
 137                 int this_len = strlen(this_name);
 138                 if (this_len < strlen(next_name) &&
 139                     strncmp(this_name, next_name, this_len) == 0 &&
 140                     next_name[this_len] == '/') {
 141                         if (10 < ++funny) {
 142                                 fprintf(stderr, "...\n");
 143                                 break;
 144                         }
 145                         fprintf(stderr, "You have both %s and %s\n",
 146                                 this_name, next_name);
 147                 }
 148         }
 149         if (funny)
 150                 die("git-write-tree: not able to write tree");
 151
 152         /* Ok, write it out */
 153         if (write_tree(active_cache, entries, "", 0, sha1) != entries)
 154                 die("git-write-tree: internal error");
 155         printf("%s\n", sha1_to_hex(sha1));
 156         return 0;
 157 }