diff --git a/Documentation/git-for-each-ref.txt b/Documentation/git-for-each-ref.txt
index eae6c0e..89158d9 100644
--- a/Documentation/git-for-each-ref.txt
+++ b/Documentation/git-for-each-ref.txt
@@ -74,6 +74,8 @@ For all objects, the following names can be used:
refname::
The name of the ref (the part after $GIT_DIR/).
+ For a non-ambiguous short name of the ref append `:short`.
+ I.e. both the full and short name will resolve to the same object.
objecttype::
The type of the object (`blob`, `tree`, `commit`, `tag`).
diff --git a/builtin-for-each-ref.c b/builtin-for-each-ref.c
index 21e92bb..6359ad7 100644
--- a/builtin-for-each-ref.c
+++ b/builtin-for-each-ref.c
@@ -546,6 +546,105 @@ static void grab_values(struct atom_value *val, int deref, struct object *obj, v
}
/*
+ * generate a format suitable for scanf from a ref_rev_parse_rules
+ * rule, that is replace the "%.*s" spec with a "%s" spec
+ */
+static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
+{
+ char *spec;
+
+ spec = strstr(rule, "%.*s");
+ if (!spec || strstr(spec + 4, "%.*s"))
+ die("invalid rule in ref_rev_parse_rules: %s", rule);
+
+ /* copy all until spec */
+ strncpy(scanf_fmt, rule, spec - rule);
+ scanf_fmt[spec - rule] = '\0';
+ /* copy new spec */
+ strcat(scanf_fmt, "%s");
+ /* copy remaining rule */
+ strcat(scanf_fmt, spec + 4);
+
+ return;
+}
+
+/*
+ * Shorten the refname to an non-ambiguous form
+ */
+static char *get_short_ref(struct refinfo *ref)
+{
+ int i;
+ static char **scanf_fmts;
+ static int nr_rules;
+ char *short_name;
+ unsigned char fullref_sha1[20];
+
+ /* pre generate scanf formats from ref_rev_parse_rules[] */
+ if (!nr_rules) {
+ size_t total_len = 0;
+
+ /* the rule list is NULL terminated, count them first */
+ for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
+ /* no +1 because strlen("%s") < strlen("%.*s") */
+ total_len += strlen(ref_rev_parse_rules[nr_rules]);
+
+ scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
+
+ total_len = 0;
+ for (i = 0; i < nr_rules; i++) {
+ scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
+ + total_len;
+ gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
+ total_len += strlen(ref_rev_parse_rules[i]);
+ }
+ }
+
+ /* bail out if there are no rules */
+ if (!nr_rules)
+ return ref->refname;
+
+ read_ref(ref->refname, fullref_sha1);
+
+ /* buffer for scanf result, at most ref->refname must fit */
+ short_name = strdup(ref->refname);
+
+ /* skip first rule, will always match */
+ for (i = 0; i < nr_rules - 1; i++) {
+ const char **p;
+ int short_name_len;
+
+ if (1 != sscanf(ref->refname, scanf_fmts[nr_rules - 1 - i],
+ short_name))
+ continue;
+
+ short_name_len = strlen(short_name);
+
+ /* check if full and short point to the same object
+ * by checking all rules in forward direction
+ */
+ for (p = ref_rev_parse_rules; *p; p++) {
+ unsigned char short_sha1[20];
+
+ /* check for valid ref */
+ if (read_ref(mkpath(*p, short_name_len, short_name),
+ short_sha1))
+ continue;
+
+ /* if the objects differ the short name is ambiguous */
+ if (hashcmp(fullref_sha1, short_sha1))
+ break;
+
+ /* ok, short and full ref point to the same object */
+ return short_name;
+ }
+ }
+
+ free(short_name);
+ return ref->refname;
+}
+
+
+/*
* Parse the object referred by ref, and grab needed value.
*/
static void populate_value(struct refinfo *ref)@@ -570,13 +669,33 @@ static void populate_value(struct refinfo *ref)
for (i = 0; i < used_atom_cnt; i++) {
const char *name = used_atom[i];
struct atom_value *v = &ref->value[i];
- if (!strcmp(name, "refname"))
- v->s = ref->refname;
- else if (!strcmp(name, "*refname")) {
- int len = strlen(ref->refname);
- char *s = xmalloc(len + 4);
- sprintf(s, "%s^{}", ref->refname);
- v->s = s;
+ int deref = 0;
+ if (*name == '*') {
+ deref = 1;
+ name++;
+ }
+ if (!prefixcmp(name, "refname")) {
+ const char *formatp = strchr(name, ':');
+ const char *refname = ref->refname;
+
+ /* look for "short" refname format */
+ if (formatp) {
+ formatp++;
+ if (!strcmp(formatp, "short"))
+ refname = get_short_ref(ref);
+ else
+ die("unknown refname format %s",
+ formatp);
+ }
+
+ if (!deref)
+ v->s = refname;
+ else {
+ int len = strlen(refname);
+ char *s = xmalloc(len + 4);
+ sprintf(s, "%s^{}", refname);
+ v->s = s;
+ }
}
}
diff --git a/t/t6300-for-each-ref.sh b/t/t6300-for-each-ref.sh
index 8ced593..ad8d48e 100755
--- a/t/t6300-for-each-ref.sh
+++ b/t/t6300-for-each-ref.sh
@@ -262,6 +262,37 @@ for i in "--perl --shell" "-s --python" "--python --tcl" "--tcl --perl"; do
"
done
+cat >expected <<\EOF
+master
+testtag
+EOF
+
+test_expect_success 'Check short refname format' '
+ (git for-each-ref --format="%(refname:short)" refs/heads &&
+ git for-each-ref --format="%(refname:short)" refs/tags) >actual &&
+ test_cmp expected actual
+'
+
+test_expect_success 'Check for invalid refname format' '
+ test_must_fail git for-each-ref --format="%(refname:INVALID)"
+'
+
+cat >expected <<\EOF
+heads/master
+master
+EOF
+
+test_expect_success 'Check ambiguous head and tag refs' '
+ git checkout -b newtag &&
+ echo "Using $datestamp" > one &&
+ git add one &&
+ git commit -m "Branch" &&
+ setdate_and_increment &&
+ git tag -m "Tagging at $datestamp" master &&
+ git for-each-ref --format "%(refname:short)" refs/heads/master refs/tags/master >actual &&
+ test_cmp expected actual
+'
+
test_expect_success 'an unusual tag with an incomplete line' '
git tag -m "bogo" bogo &&
--
1.6.0