[PATCH] Rework built-in diff to make its output more dense.

Linus says,

    The fewer lines there are that don't usually tell a human
    anything, the better. Dense is good.

This patch makes the default diff output more dense.  This
removes the previous misguided attempt to be cg-patch
compatible.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/diff.c b/diff.c
index 8659e4b04d46cb49e324d0a9fe05a0624e6ce4d3..65110333f2a71b0f4ff13094b431380089b79ffe 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -82,35 +82,32 @@ static void builtin_diff(const char *name,
                         struct diff_tempfile *temp)
 {
        int i, next_at;
-       const char *diff_cmd = "diff -L'%s%s%s' -L'%s%s%s'";
+       const char *diff_cmd = "diff -L'%s%s' -L'%s%s'";
        const char *diff_arg  = "'%s' '%s'";
        const char *input_name_sq[2];
        const char *path0[2];
        const char *path1[2];
-       char mode[2][20];
        const char *name_sq = sq_expand(name);
        char *cmd;
        
-       /* diff_cmd and diff_arg have 8 %s in total which makes
-        * the sum of these strings 16 bytes larger than required.
+       /* diff_cmd and diff_arg have 6 %s in total which makes
+        * the sum of these strings 12 bytes larger than required.
         * we use 2 spaces around diff-opts, and we need to count
-        * terminating NUL, so we subtract 13 here.
+        * terminating NUL, so we subtract 9 here.
         */
        int cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
-                       strlen(diff_arg) - 13);
+                       strlen(diff_arg) - 9);
        for (i = 0; i < 2; i++) {
                input_name_sq[i] = sq_expand(temp[i].name);
                if (!strcmp(temp[i].name, "/dev/null")) {
                        path0[i] = "/dev/null";
                        path1[i] = "";
-                       mode[i][0] = 0;
                } else {
                        path0[i] = i ? "l/" : "k/";
                        path1[i] = name_sq;
-                       sprintf(mode[i], "  (mode:%s)", temp[i].mode);
                }
                cmd_size += (strlen(path0[i]) + strlen(path1[i]) +
-                            strlen(mode[i]) + strlen(input_name_sq[i]));
+                            strlen(input_name_sq[i]));
        }
 
        cmd = xmalloc(cmd_size);
@@ -118,13 +115,20 @@ static void builtin_diff(const char *name,
        next_at = 0;
        next_at += snprintf(cmd+next_at, cmd_size-next_at,
                            diff_cmd,
-                           path0[0], path1[0], mode[0],
-                           path0[1], path1[1], mode[1]);
+                           path0[0], path1[0], path0[1], path1[1]);
        next_at += snprintf(cmd+next_at, cmd_size-next_at,
                            " %s ", diff_opts);
        next_at += snprintf(cmd+next_at, cmd_size-next_at,
                            diff_arg, input_name_sq[0], input_name_sq[1]);
 
+       if (!path1[0][0])
+               printf("Created: %s (mode:%s)\n", name, temp[1].mode);
+       else if (!path1[1][0])
+               printf("Deleted: %s\n", name);
+       else if (strcmp(temp[0].mode, temp[1].mode))
+               printf("Mode changed: %s (%s->%s)\n", name,
+                      temp[0].mode, temp[1].mode);
+       fflush(NULL);
        execlp("/bin/sh","sh", "-c", cmd, NULL);
 }