fix reflog entries for "git-branch"

Even when -l is not given from the command line, the repository
may have the configuration variable core.logallrefupdates set,
or an old-timer might have done ": >.git/logs/refs/heads/new"
before running "git branch new".  In these cases, the code gave
an uninitialized msg[] from the stack to be written out as the
reflog message.

This also passes a different message when '-f' option is used.
Saying "git branch -f branch some-commit" is a moral equilvalent
of doing "git-reset some-commit" while on the branch.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/builtin-branch.c b/builtin-branch.c
index d60690bb084ef83ce99a56453ae9dfa56da12807..eaff54ec5f045c479fa08b9d2ba5d16a5e5dee47 100644 (file)
--- a/builtin-branch.c
+++ b/builtin-branch.c
@@ -316,6 +316,7 @@ static void create_branch(const char *name, const char *start_name,
        struct commit *commit;
        unsigned char sha1[20];
        char ref[PATH_MAX], msg[PATH_MAX + 20];
+       int forcing = 0;
 
        snprintf(ref, sizeof ref, "refs/heads/%s", name);
        if (check_ref_format(ref))
@@ -326,6 +327,7 @@ static void create_branch(const char *name, const char *start_name,
                        die("A branch named '%s' already exists.", name);
                else if (!is_bare_repository() && !strcmp(head, name))
                        die("Cannot force update the current branch.");
+               forcing = 1;
        }
 
        if (start_sha1)
@@ -342,11 +344,15 @@ static void create_branch(const char *name, const char *start_name,
        if (!lock)
                die("Failed to lock ref for update: %s.", strerror(errno));
 
-       if (reflog) {
+       if (reflog)
                log_all_ref_updates = 1;
+
+       if (forcing)
+               snprintf(msg, sizeof msg, "branch: Reset from %s",
+                        start_name);
+       else
                snprintf(msg, sizeof msg, "branch: Created from %s",
                         start_name);
-       }
 
        if (write_ref_sha1(lock, sha1, msg) < 0)
                die("Failed to write ref: %s.", strerror(errno));