Enable HEAD@{...} and make it independent from the current branch

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/sha1_name.c b/sha1_name.c
index de8caf8cf6c81480f3e93edc5e3b4582a319a479..d77f77097f6e00615732c5e6d50a2c594bef4311 100644 (file)
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -235,22 +235,23 @@ static int ambiguous_path(const char *path, int len)
        return slash;
 }
 
+static const char *ref_fmt[] = {
+       "%.*s",
+       "refs/%.*s",
+       "refs/tags/%.*s",
+       "refs/heads/%.*s",
+       "refs/remotes/%.*s",
+       "refs/remotes/%.*s/HEAD",
+       NULL
+};
+
 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
 {
-       static const char *fmt[] = {
-               "%.*s",
-               "refs/%.*s",
-               "refs/tags/%.*s",
-               "refs/heads/%.*s",
-               "refs/remotes/%.*s",
-               "refs/remotes/%.*s/HEAD",
-               NULL
-       };
        const char **p, *r;
        int refs_found = 0;
 
        *ref = NULL;
-       for (p = fmt; *p; p++) {
+       for (p = ref_fmt; *p; p++) {
                unsigned char sha1_from_ref[20];
                unsigned char *this_result;
 
@@ -266,6 +267,28 @@ int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
        return refs_found;
 }
 
+static int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
+{
+       const char **p;
+       int logs_found = 0;
+
+       *log = NULL;
+       for (p = ref_fmt; *p; p++) {
+               struct stat st;
+               char *path = mkpath(*p, len, str);
+               if (!stat(git_path("logs/%s", path), &st) &&
+                   S_ISREG(st.st_mode)) {
+                       if (!logs_found++) {
+                               *log = xstrdup(path);
+                               resolve_ref(path, sha1, 0, NULL);
+                       }
+                       if (!warn_ambiguous_refs)
+                               break;
+               }
+       }
+       return logs_found;
+}
+
 static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
 {
        static const char *warning = "warning: refname '%.*s' is ambiguous.\n";
@@ -295,7 +318,9 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
        if (!len && reflog_len) {
                /* allow "@{...}" to mean the current branch reflog */
                refs_found = dwim_ref("HEAD", 4, sha1, &real_ref);
-       } else
+       } else if (reflog_len)
+               refs_found = dwim_log(str, len, sha1, &real_ref);
+       else
                refs_found = dwim_ref(str, len, sha1, &real_ref);
 
        if (!refs_found)
@@ -310,21 +335,6 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
                unsigned long co_time;
                int co_tz, co_cnt;
 
-               /*
-                * We'll have an independent reflog for "HEAD" eventually
-                * which won't be a synonym for the current branch reflog.
-                * In the mean time prevent people from getting used to
-                * such a synonym until the work is completed.
-                */
-               if (len && !strncmp("HEAD", str, len) &&
-                   !strncmp(real_ref, "refs/", 5)) {
-                       error("reflog for HEAD has not been implemented yet\n"
-                             "Maybe you could try %s%s instead, "
-                             "or just %s for current branch..",
-                             strchr(real_ref+5, '/')+1, str+len, str+len);
-                       exit(-1);
-               }
-
                /* Is it asking for N-th entry, or approxidate? */
                for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
                        char ch = str[at+2+i];