git-tar-tree: no more void pointer arithmetic

[git.git] / write-tree.c

diff --git a/write-tree.c b/write-tree.c
index d6a6058..bd07da6 100644 (file)
--- a/write-tree.c
+++ b/write-tree.c
@@ -8,8 +8,10 @@
 #include "cache-tree.h"
 
 static int missing_ok = 0;
+static char *prefix = NULL;
 
-static const char write_tree_usage[] = "git-write-tree [--missing-ok]";
+static const char write_tree_usage[] =
+"git-write-tree [--missing-ok] [--prefix=<prefix>/]";
 
 static struct lock_file lock_file;
 
@@ -21,13 +23,18 @@ int main(int argc, char **argv)
 
        newfd = hold_lock_file_for_update(&lock_file, get_index_file());
        entries = read_cache();
-       if (argc == 2) {
-               if (!strcmp(argv[1], "--missing-ok"))
+
+       while (1 < argc) {
+               char *arg = argv[1];
+               if (!strcmp(arg, "--missing-ok"))
                        missing_ok = 1;
+               else if (!strncmp(arg, "--prefix=", 9))
+                       prefix = arg + 9;
                else
                        die(write_tree_usage);
+               argc--; argv++;
        }
-       
+
        if (argc > 2)
                die("too many options");
 
@@ -54,6 +61,12 @@ int main(int argc, char **argv)
                 * performance penalty and not a big deal.
                 */
        }
-       printf("%s\n", sha1_to_hex(active_cache_tree->sha1));
+       if (prefix) {
+               struct cache_tree *subtree =
+                       cache_tree_find(active_cache_tree, prefix);
+               printf("%s\n", sha1_to_hex(subtree->sha1));
+       }
+       else
+               printf("%s\n", sha1_to_hex(active_cache_tree->sha1));
        return 0;
 }