[PATCH] Make diff-cache and friends output more cg-patch friendly.

This changes the way the default arguments to diff are built when
diff-cache and friends are invoked with -p and there is no
GIT_EXTERNAL_DIFF environment variable.  It attempts to be more cg-patch
friendly by:

 - Showing diffs against /dev/null to denote added or removed
   files;

 - Showing file modes for existing files as a comment after the
   diff label.

Unfortunately with this change GIT_DIFF_CMD customization cannot
be supported easily anymore, so it has been dropped.
GIT_DIFF_OPTS customization to change diffs from unified to
context is still there, though.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Junio C Hamano 2005-04-28 08:04:39 -07:00 committed by Linus Torvalds
parent d5e276884a
commit 2f97813870

56
diff.c
View file

@ -6,7 +6,6 @@
#include "cache.h"
#include "diff.h"
static char *diff_cmd = "diff -L'k/%s' -L'l/%s'";
static char *diff_opts = "-pu";
static const char *external_diff(void)
@ -23,14 +22,12 @@ static const char *external_diff(void)
* alternative styles you can specify via environment
* variables are:
*
* GIT_DIFF_CMD="diff -L '%s' -L '%s'"
* GIT_DIFF_OPTS="-c";
*/
if (getenv("GIT_EXTERNAL_DIFF"))
external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
/* In case external diff fails... */
diff_cmd = getenv("GIT_DIFF_CMD") ? : diff_cmd;
diff_opts = getenv("GIT_DIFF_OPTS") ? : diff_opts;
done_preparing = 1;
@ -83,31 +80,50 @@ static struct diff_tempfile {
static void builtin_diff(const char *name,
struct diff_tempfile *temp)
{
static char *diff_arg = "'%s' '%s'";
const char *name_1_sq = sq_expand(temp[0].name);
const char *name_2_sq = sq_expand(temp[1].name);
int i, next_at;
const char *diff_cmd = "diff -L'%s%s%s' -L'%s%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);
/* diff_cmd and diff_arg have 4 %s in total which makes
* the sum of these strings 8 bytes larger than required.
char *cmd;
/* diff_cmd and diff_arg have 8 %s in total which makes
* the sum of these strings 16 bytes larger than required.
* we use 2 spaces around diff-opts, and we need to count
* terminating NUL, so we subtract 5 here.
* terminating NUL, so we subtract 13 here.
*/
int cmd_size = (strlen(diff_cmd) +
strlen(name_sq) * 2 +
strlen(diff_opts) +
strlen(diff_arg) +
strlen(name_1_sq) + strlen(name_2_sq)
- 5);
char *cmd = xmalloc(cmd_size);
int next_at = 0;
int cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
strlen(diff_arg) - 13);
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]));
}
cmd = xmalloc(cmd_size);
next_at = 0;
next_at += snprintf(cmd+next_at, cmd_size-next_at,
diff_cmd, name_sq, name_sq);
diff_cmd,
path0[0], path1[0], mode[0],
path0[1], path1[1], mode[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, name_1_sq, name_2_sq);
diff_arg, input_name_sq[0], input_name_sq[1]);
execlp("/bin/sh","sh", "-c", cmd, NULL);
}