sample update-hook: sanely handle a new branch head.

diff --git a/diff-tree.c b/diff-tree.c
index d56d921585d5cd48b88bfbb36bcde016e10f8fd5..efa2b9476eae679b7f98a4605b07b6637e49de5a 100644 (file)
--- a/diff-tree.c
+++ b/diff-tree.c
@@ -14,11 +14,6 @@ static enum cmit_fmt commit_format = CMIT_FMT_RAW;
 
 static struct diff_options diff_options;
 
-static void call_diff_setup_done(void)
-{
-       diff_setup_done(&diff_options);
-}
-
 static int call_diff_flush(void)
 {
        diffcore_std(&diff_options);
@@ -43,7 +38,6 @@ static int diff_tree_sha1_top(const unsigned char *old,
 {
        int ret;
 
-       call_diff_setup_done();
        ret = diff_tree_sha1(old, new, base, &diff_options);
        call_diff_flush();
        return ret;
@@ -55,7 +49,6 @@ static int diff_root_tree(const unsigned char *new, const char *base)
        void *tree;
        struct tree_desc empty, real;
 
-       call_diff_setup_done();
        tree = read_object_with_reference(new, "tree", &real.size, NULL);
        if (!tree)
                die("unable to read root tree (%s)", sha1_to_hex(new));
@@ -69,18 +62,29 @@ static int diff_root_tree(const unsigned char *new, const char *base)
        return retval;
 }
 
-static const char *generate_header(const char *commit, const char *parent, const char *msg)
+static const char *generate_header(const unsigned char *commit_sha1,
+                                  const unsigned char *parent_sha1,
+                                  const char *msg)
 {
        static char this_header[16384];
        int offset;
        unsigned long len;
+       int abbrev = diff_options.abbrev;
 
        if (!verbose_header)
-               return commit;
+               return sha1_to_hex(commit_sha1);
 
        len = strlen(msg);
-       offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
-       offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset);
+
+       offset = sprintf(this_header, "%s%s ",
+                        header_prefix,
+                        diff_unique_abbrev(commit_sha1, abbrev));
+       offset += sprintf(this_header + offset, "(from %s)\n",
+                        parent_sha1 ?
+                        diff_unique_abbrev(parent_sha1, abbrev) : "root");
+       offset += pretty_print_commit(commit_format, msg, len,
+                                     this_header + offset,
+                                     sizeof(this_header) - offset);
        return this_header;
 }
 
@@ -99,18 +103,18 @@ static int diff_tree_commit(const unsigned char *commit_sha1)
        
        /* Root commit? */
        if (show_root_diff && !commit->parents) {
-               header = generate_header(name, "root", commit->buffer);
+               header = generate_header(sha1, NULL, commit->buffer);
                diff_root_tree(commit_sha1, "");
        }
 
        /* More than one parent? */
        if (ignore_merges && commit->parents && commit->parents->next)
-                       return 0;
+               return 0;
 
        for (parents = commit->parents; parents; parents = parents->next) {
                struct commit *parent = parents->item;
-               header = generate_header(name,
-                                        sha1_to_hex(parent->object.sha1),
+               header = generate_header(sha1,
+                                        parent->object.sha1,
                                         commit->buffer);
                diff_tree_sha1_top(parent->object.sha1, commit_sha1, "");
                if (!header && verbose_header) {
@@ -129,6 +133,7 @@ static int diff_tree_stdin(char *line)
        int len = strlen(line);
        unsigned char commit[20], parent[20];
        static char this_header[1000];
+       int abbrev = diff_options.abbrev;
 
        if (!len || line[len-1] != '\n')
                return -1;
@@ -138,7 +143,9 @@ static int diff_tree_stdin(char *line)
        if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
                line[40] = 0;
                line[81] = 0;
-               sprintf(this_header, "%s (from %s)\n", line, line+41);
+               sprintf(this_header, "%s (from %s)\n",
+                       diff_unique_abbrev(commit, abbrev),
+                       diff_unique_abbrev(parent, abbrev));
                header = this_header;
                return diff_tree_sha1_top(parent, commit, "");
        }
@@ -239,6 +246,7 @@ int main(int argc, const char **argv)
                diff_options.recursive = 1;
 
        diff_tree_setup_paths(get_pathspec(prefix, argv));
+       diff_setup_done(&diff_options);
 
        switch (nr_sha1) {
        case 0: