built-in diff: minimum tweaks

This fixes up a couple of minor issues with the real built-in
diff to be more usable:

 - Omit ---/+++ header unless we emit diff output;

 - Detect and punt binary diff like GNU does;

 - Honor GIT_DIFF_OPTS minimally (only -u<number> and
   --unified=<number> are currently supported);

 - Omit line count of 1 from "@@ -l,k +m,n @@" hunk header
   (i.e. when k == 1 or n == 1)

 - Adjust testsuite for the lack of -p support.

Signed-off-by: Junio C Hamano <junkio@cox.net>
This commit is contained in:
Junio C Hamano 2006-03-25 12:16:17 -08:00
parent 621c53cc08
commit 3ce8f08944
3 changed files with 47 additions and 12 deletions

39
diff.c
View File

@ -212,16 +212,37 @@ static int fill_mmfile(mmfile_t *mf, const char *file)
return 0;
}
struct emit_callback {
const char **label_path;
};
static int fn_out(void *priv, mmbuffer_t *mb, int nbuf)
{
int i;
struct emit_callback *ecbdata = priv;
if (ecbdata->label_path[0]) {
printf("--- %s\n", ecbdata->label_path[0]);
printf("+++ %s\n", ecbdata->label_path[1]);
ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
}
for (i = 0; i < nbuf; i++)
if (!fwrite(mb[i].ptr, mb[i].size, 1, stdout))
return -1;
return 0;
}
#define FIRST_FEW_BYTES 8000
static int mmfile_is_binary(mmfile_t *mf)
{
long sz = mf->size;
if (FIRST_FEW_BYTES < sz)
sz = FIRST_FEW_BYTES;
if (memchr(mf->ptr, 0, sz))
return 1;
return 0;
}
static const char *builtin_diff(const char *name_a,
const char *name_b,
struct diff_tempfile *temp,
@ -306,22 +327,32 @@ static const char *builtin_diff(const char *name_a,
if (label_path[1][0] != '/')
label_path[1] = quote_two("b/", name_b);
printf("--- %s\n", label_path[0]);
printf("+++ %s\n", label_path[1]);
if (fill_mmfile(&mf1, temp[0].name) < 0 ||
fill_mmfile(&mf2, temp[1].name) < 0)
die("unable to read files to diff");
if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
printf("Binary files %s and %s differ\n",
label_path[0], label_path[1]);
else {
/* Crazy xdl interfaces.. */
{
const char *diffopts = getenv("GIT_DIFF_OPTS");
xpparam_t xpp;
xdemitconf_t xecfg;
xdemitcb_t ecb;
struct emit_callback ecbdata;
ecbdata.label_path = label_path;
xpp.flags = XDF_NEED_MINIMAL;
xecfg.ctxlen = 3;
if (!diffopts)
;
else if (!strncmp(diffopts, "--unified=", 10))
xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
else if (!strncmp(diffopts, "-u", 2))
xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
ecb.outf = fn_out;
ecb.priv = &ecbdata;
xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
}

View File

@ -49,7 +49,7 @@ rename from path0
rename to path1
--- a/path0
+++ b/path1
@@ -8,7 +8,7 @@ Line 7
@@ -8,7 +8,7 @@
Line 8
Line 9
Line 10

View File

@ -245,20 +245,24 @@ int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2, xdemitcb_t *ecb) {
nb += xdl_num_out(buf + nb, c1 ? s1: 0);
if (c1 != 1) {
memcpy(buf + nb, ",", 1);
nb += 1;
nb += xdl_num_out(buf + nb, c1);
}
memcpy(buf + nb, " +", 2);
nb += 2;
nb += xdl_num_out(buf + nb, c2 ? s2: 0);
if (c2 != 1) {
memcpy(buf + nb, ",", 1);
nb += 1;
nb += xdl_num_out(buf + nb, c2);
}
memcpy(buf + nb, " @@\n", 4);
nb += 4;