Introduce usagef() that takes a printf-style format

diff --git a/builtin-diff.c b/builtin-diff.c
index 82d4ddabd85072829199fe8dc17c2de15691dac2..ffcdd055ca0b9b30bec2ce1f22e348ec15d58c81 100644 (file)
--- a/builtin-diff.c
+++ b/builtin-diff.c
@@ -70,7 +70,7 @@ static int builtin_diff_b_f(struct rev_info *revs,
                usage(builtin_diff_usage);
 
        if (lstat(path, &st))
-               die("'%s': %s", path, strerror(errno));
+               die_errno("failed to stat '%s'", path);
        if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
                die("'%s': not a regular file or symlink", path);
 
@@ -134,8 +134,8 @@ static int builtin_diff_index(struct rev_info *revs,
            revs->max_count != -1 || revs->min_age != -1 ||
            revs->max_age != -1)
                usage(builtin_diff_usage);
-       if (read_cache() < 0) {
-               perror("read_cache");
+       if (read_cache_preload(revs->diffopt.paths) < 0) {
+               perror("read_cache_preload");
                return -1;
        }
        return run_diff_index(revs, cached);
@@ -218,6 +218,8 @@ static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv
                        revs->max_count = 3;
                else if (!strcmp(argv[1], "-q"))
                        options |= DIFF_SILENT_ON_REMOVED;
+               else if (!strcmp(argv[1], "-h"))
+                       usage(builtin_diff_usage);
                else
                        return error("invalid option: %s", argv[1]);
                argv++; argc--;
@@ -234,8 +236,8 @@ static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv
                revs->combine_merges = revs->dense_combined_merges = 1;
 
        setup_work_tree();
-       if (read_cache() < 0) {
-               perror("read_cache");
+       if (read_cache_preload(revs->diffopt.paths) < 0) {
+               perror("read_cache_preload");
                return -1;
        }
        result = run_diff_files(revs, options);
@@ -290,6 +292,10 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
        /* Otherwise, we are doing the usual "git" diff */
        rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;
 
+       /* Default to let external and textconv be used */
+       DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);
+       DIFF_OPT_SET(&rev.diffopt, ALLOW_TEXTCONV);
+
        if (nongit)
                die("Not a git repository");
        argc = setup_revisions(argc, argv, &rev, NULL);
@@ -298,7 +304,7 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
                if (diff_setup_done(&rev.diffopt) < 0)
                        die("diff_setup_done failed");
        }
-       DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);
+
        DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
 
        /*