t3508: add check_head_differs_from() helper function and use it

diff --git a/refs.c b/refs.c
index d6307ae29c14d73654039bf8a92483302f4e3e15..b5400674d7a1fcf4cc16dd630b8671b2ad7b9f7b 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -314,7 +314,11 @@ static int warn_if_dangling_symref(const char *refname, const unsigned char *sha
 
 void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
 {
-       struct warn_if_dangling_data data = { fp, refname, msg_fmt };
+       struct warn_if_dangling_data data;
+
+       data.fp = fp;
+       data.refname = refname;
+       data.msg_fmt = msg_fmt;
        for_each_rawref(warn_if_dangling_symref, &data);
 }
 
@@ -1267,52 +1271,65 @@ static int copy_msg(char *buf, const char *msg)
        return cp - buf;
 }
 
-static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
-                        const unsigned char *new_sha1, const char *msg)
+int log_ref_setup(const char *ref_name, char *logfile, int bufsize)
 {
-       int logfd, written, oflags = O_APPEND | O_WRONLY;
-       unsigned maxlen, len;
-       int msglen;
-       char log_file[PATH_MAX];
-       char *logrec;
-       const char *committer;
-
-       if (log_all_ref_updates < 0)
-               log_all_ref_updates = !is_bare_repository();
-
-       git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
+       int logfd, oflags = O_APPEND | O_WRONLY;
 
+       git_snpath(logfile, bufsize, "logs/%s", ref_name);
        if (log_all_ref_updates &&
            (!prefixcmp(ref_name, "refs/heads/") ||
             !prefixcmp(ref_name, "refs/remotes/") ||
             !prefixcmp(ref_name, "refs/notes/") ||
             !strcmp(ref_name, "HEAD"))) {
-               if (safe_create_leading_directories(log_file) < 0)
+               if (safe_create_leading_directories(logfile) < 0)
                        return error("unable to create directory for %s",
-                                    log_file);
+                                    logfile);
                oflags |= O_CREAT;
        }
 
-       logfd = open(log_file, oflags, 0666);
+       logfd = open(logfile, oflags, 0666);
        if (logfd < 0) {
                if (!(oflags & O_CREAT) && errno == ENOENT)
                        return 0;
 
                if ((oflags & O_CREAT) && errno == EISDIR) {
-                       if (remove_empty_directories(log_file)) {
+                       if (remove_empty_directories(logfile)) {
                                return error("There are still logs under '%s'",
-                                            log_file);
+                                            logfile);
                        }
-                       logfd = open(log_file, oflags, 0666);
+                       logfd = open(logfile, oflags, 0666);
                }
 
                if (logfd < 0)
                        return error("Unable to append to %s: %s",
-                                    log_file, strerror(errno));
+                                    logfile, strerror(errno));
        }
 
-       adjust_shared_perm(log_file);
+       adjust_shared_perm(logfile);
+       close(logfd);
+       return 0;
+}
+
+static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
+                        const unsigned char *new_sha1, const char *msg)
+{
+       int logfd, result, written, oflags = O_APPEND | O_WRONLY;
+       unsigned maxlen, len;
+       int msglen;
+       char log_file[PATH_MAX];
+       char *logrec;
+       const char *committer;
+
+       if (log_all_ref_updates < 0)
+               log_all_ref_updates = !is_bare_repository();
 
+       result = log_ref_setup(ref_name, log_file, sizeof(log_file));
+       if (result)
+               return result;
+
+       logfd = open(log_file, oflags);
+       if (logfd < 0)
+               return 0;
        msglen = msg ? strlen(msg) : 0;
        committer = git_committer_info(0);
        maxlen = strlen(committer) + msglen + 100;