git-svn: support -C<num> passing to git-diff-tree

[git.git] / write-tree.c

diff --git a/write-tree.c b/write-tree.c
index 012eeef..d6a6058 100644 (file)
--- a/write-tree.c
+++ b/write-tree.c
@@ -4,68 +4,56 @@
  * Copyright (C) Linus Torvalds, 2005
  */
 #include "cache.h"
+#include "tree.h"
+#include "cache-tree.h"
 
-static int check_valid_sha1(unsigned char *sha1)
-{
-       char *filename = sha1_file_name(sha1);
-       int ret;
-
-       /* If we were anal, we'd check that the sha1 of the contents actually matches */
-       ret = access(filename, R_OK);
-       if (ret)
-               perror(filename);
-       return ret;
-}
+static int missing_ok = 0;
 
-static int prepend_integer(char *buffer, unsigned val, int i)
-{
-       buffer[--i] = '\0';
-       do {
-               buffer[--i] = '0' + (val % 10);
-               val /= 10;
-       } while (val);
-       return i;
-}
+static const char write_tree_usage[] = "git-write-tree [--missing-ok]";
 
-#define ORIG_OFFSET (40)       /* Enough space to add the header of "tree <size>\0" */
+static struct lock_file lock_file;
 
 int main(int argc, char **argv)
 {
-       unsigned long size, offset, val;
-       int i, entries = read_cache();
-       char *buffer;
+       int entries, was_valid, newfd;
 
-       if (entries <= 0) {
-               fprintf(stderr, "No file-cache to create a tree of\n");
-               exit(1);
-       }
+       setup_git_directory();
 
-       /* Guess at an initial size */
-       size = entries * 40 + 400;
-       buffer = malloc(size);
-       offset = ORIG_OFFSET;
-
-       for (i = 0; i < entries; i++) {
-               struct cache_entry *ce = active_cache[i];
-               if (check_valid_sha1(ce->sha1) < 0)
-                       exit(1);
-               if (offset + ce->namelen + 60 > size) {
-                       size = alloc_nr(offset + ce->namelen + 60);
-                       buffer = realloc(buffer, size);
+       newfd = hold_lock_file_for_update(&lock_file, get_index_file());
+       entries = read_cache();
+       if (argc == 2) {
+               if (!strcmp(argv[1], "--missing-ok"))
+                       missing_ok = 1;
+               else
+                       die(write_tree_usage);
+       }
+       
+       if (argc > 2)
+               die("too many options");
+
+       if (entries < 0)
+               die("git-write-tree: error reading cache");
+
+       if (!active_cache_tree)
+               active_cache_tree = cache_tree();
+
+       was_valid = cache_tree_fully_valid(active_cache_tree);
+       if (!was_valid) {
+               if (cache_tree_update(active_cache_tree,
+                                     active_cache, active_nr,
+                                     missing_ok, 0) < 0)
+                       die("git-write-tree: error building trees");
+               if (0 <= newfd) {
+                       if (!write_cache(newfd, active_cache, active_nr))
+                               commit_lock_file(&lock_file);
                }
-               offset += sprintf(buffer + offset, "%o %s", ce->st_mode, ce->name);
-               buffer[offset++] = 0;
-               memcpy(buffer + offset, ce->sha1, 20);
-               offset += 20;
+               /* Not being able to write is fine -- we are only interested
+                * in updating the cache-tree part, and if the next caller
+                * ends up using the old index with unupdated cache-tree part
+                * it misses the work we did here, but that is just a
+                * performance penalty and not a big deal.
+                */
        }
-
-       i = prepend_integer(buffer, offset - ORIG_OFFSET, ORIG_OFFSET);
-       i -= 5;
-       memcpy(buffer+i, "tree ", 5);
-
-       buffer += i;
-       offset -= i;
-
-       write_sha1_file(buffer, offset);
+       printf("%s\n", sha1_to_hex(active_cache_tree->sha1));
        return 0;
 }