зеркало из https://github.com/microsoft/git.git
420 строки
10 KiB
C
420 строки
10 KiB
C
/*
|
|
* Copyright (C) 2005 Junio C Hamano
|
|
*/
|
|
#include <sys/types.h>
|
|
#include <sys/wait.h>
|
|
#include <signal.h>
|
|
#include <limits.h>
|
|
#include "cache.h"
|
|
#include "diff.h"
|
|
|
|
static const char *diff_opts = "-pu";
|
|
|
|
static const char *external_diff(void)
|
|
{
|
|
static const char *external_diff_cmd = NULL;
|
|
static int done_preparing = 0;
|
|
|
|
if (done_preparing)
|
|
return external_diff_cmd;
|
|
|
|
/*
|
|
* Default values above are meant to match the
|
|
* Linux kernel development style. Examples of
|
|
* alternative styles you can specify via environment
|
|
* variables are:
|
|
*
|
|
* GIT_DIFF_OPTS="-c";
|
|
*/
|
|
if (gitenv("GIT_EXTERNAL_DIFF"))
|
|
external_diff_cmd = gitenv("GIT_EXTERNAL_DIFF");
|
|
|
|
/* In case external diff fails... */
|
|
diff_opts = gitenv("GIT_DIFF_OPTS") ? : diff_opts;
|
|
|
|
done_preparing = 1;
|
|
return external_diff_cmd;
|
|
}
|
|
|
|
/* Help to copy the thing properly quoted for the shell safety.
|
|
* any single quote is replaced with '\'', and the caller is
|
|
* expected to enclose the result within a single quote pair.
|
|
*
|
|
* E.g.
|
|
* original sq_expand result
|
|
* name ==> name ==> 'name'
|
|
* a b ==> a b ==> 'a b'
|
|
* a'b ==> a'\''b ==> 'a'\''b'
|
|
*/
|
|
static char *sq_expand(const char *src)
|
|
{
|
|
static char *buf = NULL;
|
|
int cnt, c;
|
|
const char *cp;
|
|
char *bp;
|
|
|
|
/* count bytes needed to store the quoted string. */
|
|
for (cnt = 1, cp = src; *cp; cnt++, cp++)
|
|
if (*cp == '\'')
|
|
cnt += 3;
|
|
|
|
buf = xmalloc(cnt);
|
|
bp = buf;
|
|
while ((c = *src++)) {
|
|
if (c != '\'')
|
|
*bp++ = c;
|
|
else {
|
|
bp = strcpy(bp, "'\\''");
|
|
bp += 4;
|
|
}
|
|
}
|
|
*bp = 0;
|
|
return buf;
|
|
}
|
|
|
|
static struct diff_tempfile {
|
|
const char *name;
|
|
char hex[41];
|
|
char mode[10];
|
|
char tmp_path[50];
|
|
} diff_temp[2];
|
|
|
|
static void builtin_diff(const char *name_a,
|
|
const char *name_b,
|
|
struct diff_tempfile *temp)
|
|
{
|
|
int i, next_at;
|
|
const char *diff_cmd = "diff -L'%s%s' -L'%s%s'";
|
|
const char *diff_arg = "'%s' '%s'||:"; /* "||:" is to return 0 */
|
|
const char *input_name_sq[2];
|
|
const char *path0[2];
|
|
const char *path1[2];
|
|
const char *name_sq[2];
|
|
char *cmd;
|
|
|
|
name_sq[0] = sq_expand(name_a);
|
|
name_sq[1] = sq_expand(name_b);
|
|
|
|
/* 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 9 here.
|
|
*/
|
|
int cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
|
|
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] = "";
|
|
} else {
|
|
path0[i] = i ? "b/" : "a/";
|
|
path1[i] = name_sq[i];
|
|
}
|
|
cmd_size += (strlen(path0[i]) + strlen(path1[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,
|
|
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]);
|
|
|
|
printf("diff --git a/%s b/%s\n", name_a, name_b);
|
|
if (!path1[0][0])
|
|
printf("new file mode %s\n", temp[1].mode);
|
|
else if (!path1[1][0])
|
|
printf("deleted file mode %s\n", temp[0].mode);
|
|
else {
|
|
if (strcmp(temp[0].mode, temp[1].mode)) {
|
|
printf("old mode %s\n", temp[0].mode);
|
|
printf("new mode %s\n", temp[1].mode);
|
|
}
|
|
if (strcmp(name_a, name_b)) {
|
|
printf("rename old %s\n", name_a);
|
|
printf("rename new %s\n", name_b);
|
|
}
|
|
if (strncmp(temp[0].mode, temp[1].mode, 3))
|
|
/* we do not run diff between different kind
|
|
* of objects.
|
|
*/
|
|
exit(0);
|
|
}
|
|
fflush(NULL);
|
|
execlp("/bin/sh","sh", "-c", cmd, NULL);
|
|
}
|
|
|
|
/*
|
|
* Given a name and sha1 pair, if the dircache tells us the file in
|
|
* the work tree has that object contents, return true, so that
|
|
* prepare_temp_file() does not have to inflate and extract.
|
|
*/
|
|
static int work_tree_matches(const char *name, const unsigned char *sha1)
|
|
{
|
|
struct cache_entry *ce;
|
|
struct stat st;
|
|
int pos, len;
|
|
|
|
/* We do not read the cache ourselves here, because the
|
|
* benchmark with my previous version that always reads cache
|
|
* shows that it makes things worse for diff-tree comparing
|
|
* two linux-2.6 kernel trees in an already checked out work
|
|
* tree. This is because most diff-tree comparisons deal with
|
|
* only a small number of files, while reading the cache is
|
|
* expensive for a large project, and its cost outweighs the
|
|
* savings we get by not inflating the object to a temporary
|
|
* file. Practically, this code only helps when we are used
|
|
* by diff-cache --cached, which does read the cache before
|
|
* calling us.
|
|
*/
|
|
if (!active_cache)
|
|
return 0;
|
|
|
|
len = strlen(name);
|
|
pos = cache_name_pos(name, len);
|
|
if (pos < 0)
|
|
return 0;
|
|
ce = active_cache[pos];
|
|
if ((lstat(name, &st) < 0) ||
|
|
!S_ISREG(st.st_mode) ||
|
|
ce_match_stat(ce, &st) ||
|
|
memcmp(sha1, ce->sha1, 20))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
static void prep_temp_blob(struct diff_tempfile *temp,
|
|
void *blob,
|
|
unsigned long size,
|
|
unsigned char *sha1,
|
|
int mode)
|
|
{
|
|
int fd;
|
|
|
|
strcpy(temp->tmp_path, ".diff_XXXXXX");
|
|
fd = mkstemp(temp->tmp_path);
|
|
if (fd < 0)
|
|
die("unable to create temp-file");
|
|
if (write(fd, blob, size) != size)
|
|
die("unable to write temp-file");
|
|
close(fd);
|
|
temp->name = temp->tmp_path;
|
|
strcpy(temp->hex, sha1_to_hex(sha1));
|
|
temp->hex[40] = 0;
|
|
sprintf(temp->mode, "%06o", mode);
|
|
}
|
|
|
|
static void prepare_temp_file(const char *name,
|
|
struct diff_tempfile *temp,
|
|
struct diff_spec *one)
|
|
{
|
|
static unsigned char null_sha1[20] = { 0, };
|
|
int use_work_tree = 0;
|
|
|
|
if (!one->file_valid) {
|
|
not_a_valid_file:
|
|
/* A '-' entry produces this for file-2, and
|
|
* a '+' entry produces this for file-1.
|
|
*/
|
|
temp->name = "/dev/null";
|
|
strcpy(temp->hex, ".");
|
|
strcpy(temp->mode, ".");
|
|
return;
|
|
}
|
|
|
|
if (one->sha1_valid &&
|
|
(!memcmp(one->blob_sha1, null_sha1, sizeof(null_sha1)) ||
|
|
work_tree_matches(name, one->blob_sha1)))
|
|
use_work_tree = 1;
|
|
|
|
if (!one->sha1_valid || use_work_tree) {
|
|
struct stat st;
|
|
temp->name = name;
|
|
if (lstat(temp->name, &st) < 0) {
|
|
if (errno == ENOENT)
|
|
goto not_a_valid_file;
|
|
die("stat(%s): %s", temp->name, strerror(errno));
|
|
}
|
|
if (S_ISLNK(st.st_mode)) {
|
|
int ret;
|
|
char *buf, buf_[1024];
|
|
buf = ((sizeof(buf_) < st.st_size) ?
|
|
xmalloc(st.st_size) : buf_);
|
|
ret = readlink(name, buf, st.st_size);
|
|
if (ret < 0)
|
|
die("readlink(%s)", name);
|
|
prep_temp_blob(temp, buf, st.st_size,
|
|
(one->sha1_valid ?
|
|
one->blob_sha1 : null_sha1),
|
|
(one->sha1_valid ?
|
|
one->mode : S_IFLNK));
|
|
}
|
|
else {
|
|
if (!one->sha1_valid)
|
|
strcpy(temp->hex, sha1_to_hex(null_sha1));
|
|
else
|
|
strcpy(temp->hex, sha1_to_hex(one->blob_sha1));
|
|
sprintf(temp->mode, "%06o",
|
|
S_IFREG |ce_permissions(st.st_mode));
|
|
}
|
|
return;
|
|
}
|
|
else {
|
|
void *blob;
|
|
char type[20];
|
|
unsigned long size;
|
|
|
|
blob = read_sha1_file(one->blob_sha1, type, &size);
|
|
if (!blob || strcmp(type, "blob"))
|
|
die("unable to read blob object for %s (%s)",
|
|
name, sha1_to_hex(one->blob_sha1));
|
|
prep_temp_blob(temp, blob, size, one->blob_sha1, one->mode);
|
|
free(blob);
|
|
}
|
|
}
|
|
|
|
static void remove_tempfile(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < 2; i++)
|
|
if (diff_temp[i].name == diff_temp[i].tmp_path) {
|
|
unlink(diff_temp[i].name);
|
|
diff_temp[i].name = NULL;
|
|
}
|
|
}
|
|
|
|
static void remove_tempfile_on_signal(int signo)
|
|
{
|
|
remove_tempfile();
|
|
}
|
|
|
|
/* An external diff command takes:
|
|
*
|
|
* diff-cmd name infile1 infile1-sha1 infile1-mode \
|
|
* infile2 infile2-sha1 infile2-mode.
|
|
*
|
|
*/
|
|
void run_external_diff(const char *name,
|
|
const char *other,
|
|
struct diff_spec *one,
|
|
struct diff_spec *two)
|
|
{
|
|
struct diff_tempfile *temp = diff_temp;
|
|
pid_t pid;
|
|
int status;
|
|
static int atexit_asked = 0;
|
|
|
|
if (one && two) {
|
|
prepare_temp_file(name, &temp[0], one);
|
|
prepare_temp_file(other ? : name, &temp[1], two);
|
|
if (! atexit_asked &&
|
|
(temp[0].name == temp[0].tmp_path ||
|
|
temp[1].name == temp[1].tmp_path)) {
|
|
atexit_asked = 1;
|
|
atexit(remove_tempfile);
|
|
}
|
|
signal(SIGINT, remove_tempfile_on_signal);
|
|
}
|
|
|
|
fflush(NULL);
|
|
pid = fork();
|
|
if (pid < 0)
|
|
die("unable to fork");
|
|
if (!pid) {
|
|
const char *pgm = external_diff();
|
|
/* not passing rename patch to external ones */
|
|
if (!other && pgm) {
|
|
if (one && two)
|
|
execlp(pgm, pgm,
|
|
name,
|
|
temp[0].name, temp[0].hex, temp[0].mode,
|
|
temp[1].name, temp[1].hex, temp[1].mode,
|
|
NULL);
|
|
else
|
|
execlp(pgm, pgm, name, NULL);
|
|
}
|
|
/*
|
|
* otherwise we use the built-in one.
|
|
*/
|
|
if (one && two)
|
|
builtin_diff(name, other ? : name, temp);
|
|
else
|
|
printf("* Unmerged path %s\n", name);
|
|
exit(0);
|
|
}
|
|
if (waitpid(pid, &status, 0) < 0 ||
|
|
!WIFEXITED(status) || WEXITSTATUS(status)) {
|
|
/* Earlier we did not check the exit status because
|
|
* diff exits non-zero if files are different, and
|
|
* we are not interested in knowing that. It was a
|
|
* mistake which made it harder to quit a diff-*
|
|
* session that uses the git-apply-patch-script as
|
|
* the GIT_EXTERNAL_DIFF. A custom GIT_EXTERNAL_DIFF
|
|
* should also exit non-zero only when it wants to
|
|
* abort the entire diff-* session.
|
|
*/
|
|
remove_tempfile();
|
|
fprintf(stderr, "external diff died, stopping at %s.\n", name);
|
|
exit(1);
|
|
}
|
|
remove_tempfile();
|
|
}
|
|
|
|
void diff_addremove(int addremove, unsigned mode,
|
|
const unsigned char *sha1,
|
|
const char *base, const char *path)
|
|
{
|
|
char concatpath[PATH_MAX];
|
|
struct diff_spec spec[2], *one, *two;
|
|
|
|
memcpy(spec[0].blob_sha1, sha1, 20);
|
|
spec[0].mode = mode;
|
|
spec[0].sha1_valid = spec[0].file_valid = 1;
|
|
spec[1].file_valid = 0;
|
|
|
|
if (addremove == '+') {
|
|
one = spec + 1; two = spec;
|
|
} else {
|
|
one = spec; two = one + 1;
|
|
}
|
|
|
|
if (path) {
|
|
strcpy(concatpath, base);
|
|
strcat(concatpath, path);
|
|
}
|
|
run_external_diff(path ? concatpath : base, NULL, one, two);
|
|
}
|
|
|
|
void diff_change(unsigned old_mode, unsigned new_mode,
|
|
const unsigned char *old_sha1,
|
|
const unsigned char *new_sha1,
|
|
const char *base, const char *path) {
|
|
char concatpath[PATH_MAX];
|
|
struct diff_spec spec[2];
|
|
|
|
memcpy(spec[0].blob_sha1, old_sha1, 20);
|
|
spec[0].mode = old_mode;
|
|
memcpy(spec[1].blob_sha1, new_sha1, 20);
|
|
spec[1].mode = new_mode;
|
|
spec[0].sha1_valid = spec[0].file_valid = 1;
|
|
spec[1].sha1_valid = spec[1].file_valid = 1;
|
|
|
|
if (path) {
|
|
strcpy(concatpath, base);
|
|
strcat(concatpath, path);
|
|
}
|
|
run_external_diff(path ? concatpath : base, NULL, &spec[0], &spec[1]);
|
|
}
|
|
|
|
void diff_unmerge(const char *path)
|
|
{
|
|
run_external_diff(path, NULL, NULL, NULL);
|
|
}
|