#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
+#include <limits.h>
#include "cache.h"
#include "diff.h"
-static char *diff_opts = "-pu";
+static const char *diff_opts = "-pu";
static const char *external_diff(void)
{
- static char *external_diff_cmd = NULL;
+ static const char *external_diff_cmd = NULL;
static int done_preparing = 0;
if (done_preparing)
*
* GIT_DIFF_OPTS="-c";
*/
- if (getenv("GIT_EXTERNAL_DIFF"))
- external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
+ if (gitenv("GIT_EXTERNAL_DIFF"))
+ external_diff_cmd = gitenv("GIT_EXTERNAL_DIFF");
/* In case external diff fails... */
- diff_opts = getenv("GIT_DIFF_OPTS") ? : diff_opts;
+ diff_opts = gitenv("GIT_DIFF_OPTS") ? : diff_opts;
done_preparing = 1;
return external_diff_cmd;
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))
+ else if (strcmp(temp[0].mode, temp[1].mode)) {
printf("Mode changed: %s (%s->%s)\n", name,
temp[0].mode, temp[1].mode);
+ /* Be careful. We do not want to diff between
+ * symlink and a file.
+ */
+ if (strncmp(temp[0].mode, "120", 3) !=
+ strncmp(temp[1].mode, "120", 3))
+ 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 comparison deals 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) ||
+ cache_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:
}
if (one->sha1_valid &&
- !memcmp(one->u.sha1, null_sha1, sizeof(null_sha1))) {
- one->sha1_valid = 0;
- one->u.name = name;
- }
+ (!memcmp(one->blob_sha1, null_sha1, sizeof(null_sha1)) ||
+ work_tree_matches(name, one->blob_sha1)))
+ use_work_tree = 1;
- if (!one->sha1_valid) {
+ if (!one->sha1_valid || use_work_tree) {
struct stat st;
- temp->name = one->u.name;
- if (stat(temp->name, &st) < 0) {
+ 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));
}
- strcpy(temp->hex, sha1_to_hex(null_sha1));
- sprintf(temp->mode, "%06o",
- S_IFREG |ce_permissions(st.st_mode));
+ 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 {
- int fd;
void *blob;
char type[20];
unsigned long size;
- blob = read_sha1_file(one->u.sha1, type, &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->u.sha1));
-
- 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);
+ name, sha1_to_hex(one->blob_sha1));
+ prep_temp_blob(temp, blob, size, one->blob_sha1, one->mode);
free(blob);
- temp->name = temp->tmp_path;
- strcpy(temp->hex, sha1_to_hex(one->u.sha1));
- temp->hex[40] = 0;
- sprintf(temp->mode, "%06o", one->mode);
}
}
char concatpath[PATH_MAX];
struct diff_spec spec[2], *one, *two;
- memcpy(spec[0].u.sha1, sha1, 20);
+ 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;
char concatpath[PATH_MAX];
struct diff_spec spec[2];
- memcpy(spec[0].u.sha1, old_sha1, 20);
+ memcpy(spec[0].blob_sha1, old_sha1, 20);
spec[0].mode = old_mode;
- memcpy(spec[1].u.sha1, new_sha1, 20);
+ 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;