diff.c
/*
* Copyright (C) 2005 Junio C Hamano
*/
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#include "cache.h"
#include "quote.h"
#include "diff.h"
#include "diffcore.h"
static const char *diff_opts = "-pu";
static int use_size_cache;
static const char *external_diff(void)
{
static const char *external_diff_cmd = NULL;
static int done_preparing = 0;
const char *env_diff_opts;
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";
*/
external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
/* In case external diff fails... */
env_diff_opts = getenv("GIT_DIFF_OPTS");
if (env_diff_opts) diff_opts = env_diff_opts;
done_preparing = 1;
return external_diff_cmd;
}
#define TEMPFILE_PATH_LEN 50
static struct diff_tempfile {
const char *name; /* filename external diff should read from */
char hex[41];
char mode[10];
char tmp_path[TEMPFILE_PATH_LEN];
} diff_temp[2];
static int count_lines(const char *filename)
{
FILE *in;
int count, ch, completely_empty = 1, nl_just_seen = 0;
in = fopen(filename, "r");
count = 0;
while ((ch = fgetc(in)) != EOF)
if (ch == '\n') {
count++;
nl_just_seen = 1;
completely_empty = 0;
}
else {
nl_just_seen = 0;
completely_empty = 0;
}
fclose(in);
if (completely_empty)
return 0;
if (!nl_just_seen)
count++; /* no trailing newline */
return count;
}
static void print_line_count(int count)
{
switch (count) {
case 0:
printf("0,0");
break;
case 1:
printf("1");
break;
default:
printf("1,%d", count);
break;
}
}
static void copy_file(int prefix, const char *filename)
{
FILE *in;
int ch, nl_just_seen = 1;
in = fopen(filename, "r");
while ((ch = fgetc(in)) != EOF) {
if (nl_just_seen)
putchar(prefix);
putchar(ch);
if (ch == '\n')
nl_just_seen = 1;
else
nl_just_seen = 0;
}
fclose(in);
if (!nl_just_seen)
printf("\n\\ No newline at end of file\n");
}
static void emit_rewrite_diff(const char *name_a,
const char *name_b,
struct diff_tempfile *temp)
{
/* Use temp[i].name as input, name_a and name_b as labels */
int lc_a, lc_b;
lc_a = count_lines(temp[0].name);
lc_b = count_lines(temp[1].name);
printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
print_line_count(lc_a);
printf(" +");
print_line_count(lc_b);
printf(" @@\n");
if (lc_a)
copy_file('-', temp[0].name);
if (lc_b)
copy_file('+', temp[1].name);
}
static void builtin_diff(const char *name_a,
const char *name_b,
struct diff_tempfile *temp,
const char *xfrm_msg,
int complete_rewrite)
{
int i, next_at, cmd_size;
const char *const diff_cmd = "diff -L%s%s -L%s%s";
const char *const 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_quote(name_a);
name_sq[1] = sq_quote(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.
*/
cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
strlen(diff_arg) - 9);
for (i = 0; i < 2; i++) {
input_name_sq[i] = sq_quote(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);
if (xfrm_msg && xfrm_msg[0])
puts(xfrm_msg);
}
else if (!path1[1][0]) {
printf("deleted file mode %s\n", temp[0].mode);
if (xfrm_msg && xfrm_msg[0])
puts(xfrm_msg);
}
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 (xfrm_msg && xfrm_msg[0])
puts(xfrm_msg);
if (strncmp(temp[0].mode, temp[1].mode, 3))
/* we do not run diff between different kind
* of objects.
*/
exit(0);
if (complete_rewrite) {
fflush(NULL);
emit_rewrite_diff(name_a, name_b, temp);
exit(0);
}
}
fflush(NULL);
execlp("/bin/sh","sh", "-c", cmd, NULL);
}
struct diff_filespec *alloc_filespec(const char *path)
{
int namelen = strlen(path);
struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
memset(spec, 0, sizeof(*spec));
spec->path = (char *)(spec + 1);
memcpy(spec->path, path, namelen+1);
return spec;
}
void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
unsigned short mode)
{
if (mode) {
spec->mode = DIFF_FILE_CANON_MODE(mode);
memcpy(spec->sha1, sha1, 20);
spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
}
}
/*
* 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) || /* careful! */
ce_match_stat(ce, &st) ||
memcmp(sha1, ce->sha1, 20))
return 0;
/* we return 1 only when we can stat, it is a regular file,
* stat information matches, and sha1 recorded in the cache
* matches. I.e. we know the file in the work tree really is
* the same as the <name, sha1> pair.
*/
return 1;
}
static struct sha1_size_cache {
unsigned char sha1[20];
unsigned long size;
} **sha1_size_cache;
static int sha1_size_cache_nr, sha1_size_cache_alloc;
static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
int find_only,
unsigned long size)
{
int first, last;
struct sha1_size_cache *e;
first = 0;
last = sha1_size_cache_nr;
while (last > first) {
int cmp, next = (last + first) >> 1;
e = sha1_size_cache[next];
cmp = memcmp(e->sha1, sha1, 20);
if (!cmp)
return e;
if (cmp < 0) {
last = next;
continue;
}
first = next+1;
}
/* not found */
if (find_only)
return NULL;
/* insert to make it at "first" */
if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
sha1_size_cache = xrealloc(sha1_size_cache,
sha1_size_cache_alloc *
sizeof(*sha1_size_cache));
}
sha1_size_cache_nr++;
if (first < sha1_size_cache_nr)
memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
(sha1_size_cache_nr - first - 1) *
sizeof(*sha1_size_cache));
e = xmalloc(sizeof(struct sha1_size_cache));
sha1_size_cache[first] = e;
memcpy(e->sha1, sha1, 20);
e->size = size;
return e;
}
/*
* While doing rename detection and pickaxe operation, we may need to
* grab the data for the blob (or file) for our own in-core comparison.
* diff_filespec has data and size fields for this purpose.
*/
int diff_populate_filespec(struct diff_filespec *s, int size_only)
{
int err = 0;
if (!DIFF_FILE_VALID(s))
die("internal error: asking to populate invalid file.");
if (S_ISDIR(s->mode))
return -1;
if (!use_size_cache)
size_only = 0;
if (s->data)
return err;
if (!s->sha1_valid ||
work_tree_matches(s->path, s->sha1)) {
struct stat st;
int fd;
if (lstat(s->path, &st) < 0) {
if (errno == ENOENT) {
err_empty:
err = -1;
empty:
s->data = "";
s->size = 0;
return err;
}
}
s->size = st.st_size;
if (!s->size)
goto empty;
if (size_only)
return 0;
if (S_ISLNK(st.st_mode)) {
int ret;
s->data = xmalloc(s->size);
s->should_free = 1;
ret = readlink(s->path, s->data, s->size);
if (ret < 0) {
free(s->data);
goto err_empty;
}
return 0;
}
fd = open(s->path, O_RDONLY);
if (fd < 0)
goto err_empty;
s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
close(fd);
if (s->data == MAP_FAILED)
goto err_empty;
s->should_munmap = 1;
}
else {
char type[20];
struct sha1_size_cache *e;
if (size_only) {
e = locate_size_cache(s->sha1, 1, 0);
if (e) {
s->size = e->size;
return 0;
}
if (!sha1_object_info(s->sha1, type, &s->size))
locate_size_cache(s->sha1, 0, s->size);
}
else {
s->data = read_sha1_file(s->sha1, type, &s->size);
s->should_free = 1;
}
}
return 0;
}
void diff_free_filespec_data(struct diff_filespec *s)
{
if (s->should_free)
free(s->data);
else if (s->should_munmap)
munmap(s->data, s->size);
s->should_free = s->should_munmap = 0;
s->data = NULL;
}
static void prep_temp_blob(struct diff_tempfile *temp,
void *blob,
unsigned long size,
const unsigned char *sha1,
int mode)
{
int fd;
fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
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_filespec *one)
{
if (!DIFF_FILE_VALID(one)) {
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 ||
work_tree_matches(name, one->sha1)) {
struct stat st;
if (lstat(name, &st) < 0) {
if (errno == ENOENT)
goto not_a_valid_file;
die("stat(%s): %s", 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->sha1 : null_sha1),
(one->sha1_valid ?
one->mode : S_IFLNK));
}
else {
/* we can borrow from the file in the work tree */
temp->name = name;
if (!one->sha1_valid)
strcpy(temp->hex, sha1_to_hex(null_sha1));
else
strcpy(temp->hex, sha1_to_hex(one->sha1));
/* Even though we may sometimes borrow the
* contents from the work tree, we always want
* one->mode. mode is trustworthy even when
* !(one->sha1_valid), as long as
* DIFF_FILE_VALID(one).
*/
sprintf(temp->mode, "%06o", one->mode);
}
return;
}
else {
if (diff_populate_filespec(one, 0))
die("cannot read data blob for %s", one->path);
prep_temp_blob(temp, one->data, one->size,
one->sha1, one->mode);
}
}
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 [ rename-to ]
*
*/
static void run_external_diff(const char *pgm,
const char *name,
const char *other,
struct diff_filespec *one,
struct diff_filespec *two,
const char *xfrm_msg,
int complete_rewrite)
{
struct diff_tempfile *temp = diff_temp;
pid_t pid;
int status;
static int atexit_asked = 0;
const char *othername;
othername = (other? other : name);
if (one && two) {
prepare_temp_file(name, &temp[0], one);
prepare_temp_file(othername, &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) {
if (pgm) {
if (one && two) {
const char *exec_arg[10];
const char **arg = &exec_arg[0];
*arg++ = pgm;
*arg++ = name;
*arg++ = temp[0].name;
*arg++ = temp[0].hex;
*arg++ = temp[0].mode;
*arg++ = temp[1].name;
*arg++ = temp[1].hex;
*arg++ = temp[1].mode;
if (other) {
*arg++ = other;
*arg++ = xfrm_msg;
}
*arg = NULL;
execvp(pgm, (char *const*) exec_arg);
}
else
execlp(pgm, pgm, name, NULL);
}
/*
* otherwise we use the built-in one.
*/
if (one && two)
builtin_diff(name, othername, temp, xfrm_msg,
complete_rewrite);
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();
}
static void run_diff(struct diff_filepair *p)
{
const char *pgm = external_diff();
char msg_[PATH_MAX*2+200], *xfrm_msg;
struct diff_filespec *one;
struct diff_filespec *two;
const char *name;
const char *other;
int complete_rewrite = 0;
if (DIFF_PAIR_UNMERGED(p)) {
/* unmerged */
run_external_diff(pgm, p->one->path, NULL, NULL, NULL, NULL,
0);
return;
}
name = p->one->path;
other = (strcmp(name, p->two->path) ? p->two->path : NULL);
one = p->one; two = p->two;
switch (p->status) {
case DIFF_STATUS_COPIED:
sprintf(msg_,
"similarity index %d%%\n"
"copy from %s\n"
"copy to %s",
(int)(0.5 + p->score * 100.0/MAX_SCORE),
name, other);
xfrm_msg = msg_;
break;
case DIFF_STATUS_RENAMED:
sprintf(msg_,
"similarity index %d%%\n"
"rename from %s\n"
"rename to %s",
(int)(0.5 + p->score * 100.0/MAX_SCORE),
name, other);
xfrm_msg = msg_;
break;
case DIFF_STATUS_MODIFIED:
if (p->score) {
sprintf(msg_,
"dissimilarity index %d%%",
(int)(0.5 + p->score * 100.0/MAX_SCORE));
xfrm_msg = msg_;
complete_rewrite = 1;
break;
}
/* fallthru */
default:
xfrm_msg = NULL;
}
if (!pgm &&
DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
(S_IFMT & one->mode) != (S_IFMT & two->mode)) {
/* a filepair that changes between file and symlink
* needs to be split into deletion and creation.
*/
struct diff_filespec *null = alloc_filespec(two->path);
run_external_diff(NULL, name, other, one, null, xfrm_msg, 0);
free(null);
null = alloc_filespec(one->path);
run_external_diff(NULL, name, other, null, two, xfrm_msg, 0);
free(null);
}
else
run_external_diff(pgm, name, other, one, two, xfrm_msg,
complete_rewrite);
}
void diff_setup(struct diff_options *options)
{
memset(options, 0, sizeof(*options));
options->output_format = DIFF_FORMAT_RAW;
options->line_termination = '\n';
options->break_opt = -1;
options->rename_limit = -1;
}
int diff_setup_done(struct diff_options *options)
{
if ((options->find_copies_harder || 0 <= options->rename_limit) &&
options->detect_rename != DIFF_DETECT_COPY)
return -1;
if (options->setup & DIFF_SETUP_USE_CACHE) {
if (!active_cache)
/* read-cache does not die even when it fails
* so it is safe for us to do this here. Also
* it does not smudge active_cache or active_nr
* when it fails, so we do not have to worry about
* cleaning it up oufselves either.
*/
read_cache();
}
if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
use_size_cache = 1;
return 0;
}
int diff_opt_parse(struct diff_options *options, const char **av, int ac)
{
const char *arg = av[0];
if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
options->output_format = DIFF_FORMAT_PATCH;
else if (!strcmp(arg, "-z"))
options->line_termination = 0;
else if (!strncmp(arg, "-l", 2))
options->rename_limit = strtoul(arg+2, NULL, 10);
else if (!strcmp(arg, "--name-only"))
options->output_format = DIFF_FORMAT_NAME;
else if (!strcmp(arg, "--name-status"))
options->output_format = DIFF_FORMAT_NAME_STATUS;
else if (!strcmp(arg, "-R"))
options->reverse_diff = 1;
else if (!strncmp(arg, "-S", 2))
options->pickaxe = arg + 2;
else if (!strcmp(arg, "-s"))
options->output_format = DIFF_FORMAT_NO_OUTPUT;
else if (!strncmp(arg, "-O", 2))
options->orderfile = arg + 2;
else if (!strncmp(arg, "--diff-filter=", 14))
options->filter = arg + 14;
else if (!strcmp(arg, "--pickaxe-all"))
options->pickaxe_opts = DIFF_PICKAXE_ALL;
else if (!strncmp(arg, "-B", 2)) {
if ((options->break_opt =
diff_scoreopt_parse(arg)) == -1)
return -1;
}
else if (!strncmp(arg, "-M", 2)) {
if ((options->rename_score =
diff_scoreopt_parse(arg)) == -1)
return -1;
options->detect_rename = DIFF_DETECT_RENAME;
}
else if (!strncmp(arg, "-C", 2)) {
if ((options->rename_score =
diff_scoreopt_parse(arg)) == -1)
return -1;
options->detect_rename = DIFF_DETECT_COPY;
}
else if (!strcmp(arg, "--find-copies-harder"))
options->find_copies_harder = 1;
else
return 0;
return 1;
}
static int parse_num(const char **cp_p)
{
int num, scale, ch, cnt;
const char *cp = *cp_p;
cnt = num = 0;
scale = 1;
while ('0' <= (ch = *cp) && ch <= '9') {
if (cnt++ < 5) {
/* We simply ignore more than 5 digits precision. */
scale *= 10;
num = num * 10 + ch - '0';
}
cp++;
}
*cp_p = cp;
/* user says num divided by scale and we say internally that
* is MAX_SCORE * num / scale.
*/
return (MAX_SCORE * num / scale);
}
int diff_scoreopt_parse(const char *opt)
{
int opt1, opt2, cmd;
if (*opt++ != '-')
return -1;
cmd = *opt++;
if (cmd != 'M' && cmd != 'C' && cmd != 'B')
return -1; /* that is not a -M, -C nor -B option */
opt1 = parse_num(&opt);
if (cmd != 'B')
opt2 = 0;
else {
if (*opt == 0)
opt2 = 0;
else if (*opt != '/')
return -1; /* we expect -B80/99 or -B80 */
else {
opt++;
opt2 = parse_num(&opt);
}
}
if (*opt != 0)
return -1;
return opt1 | (opt2 << 16);
}
struct diff_queue_struct diff_queued_diff;
void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
{
if (queue->alloc <= queue->nr) {
queue->alloc = alloc_nr(queue->alloc);
queue->queue = xrealloc(queue->queue,
sizeof(dp) * queue->alloc);
}
queue->queue[queue->nr++] = dp;
}
struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
struct diff_filespec *one,
struct diff_filespec *two)
{
struct diff_filepair *dp = xmalloc(sizeof(*dp));
dp->one = one;
dp->two = two;
dp->score = 0;
dp->status = 0;
dp->source_stays = 0;
dp->broken_pair = 0;
if (queue)
diff_q(queue, dp);
return dp;
}
void diff_free_filepair(struct diff_filepair *p)
{
diff_free_filespec_data(p->one);
diff_free_filespec_data(p->two);
free(p->one);
free(p->two);
free(p);
}
static void diff_flush_raw(struct diff_filepair *p,
int line_termination,
int inter_name_termination,
int output_format)
{
int two_paths;
char status[10];
if (line_termination) {
const char *const err =
"path %s cannot be expressed without -z";
if (strchr(p->one->path, line_termination) ||
strchr(p->one->path, inter_name_termination))
die(err, p->one->path);
if (strchr(p->two->path, line_termination) ||
strchr(p->two->path, inter_name_termination))
die(err, p->two->path);
}
if (p->score)
sprintf(status, "%c%03d", p->status,
(int)(0.5 + p->score * 100.0/MAX_SCORE));
else {
status[0] = p->status;
status[1] = 0;
}
switch (p->status) {
case DIFF_STATUS_COPIED:
case DIFF_STATUS_RENAMED:
two_paths = 1;
break;
case DIFF_STATUS_ADDED:
case DIFF_STATUS_DELETED:
two_paths = 0;
break;
default:
two_paths = 0;
break;
}
if (output_format != DIFF_FORMAT_NAME_STATUS) {
printf(":%06o %06o %s ",
p->one->mode, p->two->mode, sha1_to_hex(p->one->sha1));
printf("%s ", sha1_to_hex(p->two->sha1));
}
printf("%s%c%s",status, inter_name_termination, p->one->path);
if (two_paths)
printf("%c%s", inter_name_termination, p->two->path);
putchar(line_termination);
}
static void diff_flush_name(struct diff_filepair *p,
int line_termination)
{
printf("%s%c", p->two->path, line_termination);
}
int diff_unmodified_pair(struct diff_filepair *p)
{
/* This function is written stricter than necessary to support
* the currently implemented transformers, but the idea is to
* let transformers to produce diff_filepairs any way they want,
* and filter and clean them up here before producing the output.
*/
struct diff_filespec *one, *two;
if (DIFF_PAIR_UNMERGED(p))
return 0; /* unmerged is interesting */
one = p->one;
two = p->two;
/* deletion, addition, mode or type change
* and rename are all interesting.
*/
if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
DIFF_PAIR_MODE_CHANGED(p) ||
strcmp(one->path, two->path))
return 0;
/* both are valid and point at the same path. that is, we are
* dealing with a change.
*/
if (one->sha1_valid && two->sha1_valid &&
!memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
return 1; /* no change */
if (!one->sha1_valid && !two->sha1_valid)
return 1; /* both look at the same file on the filesystem. */
return 0;
}
static void diff_flush_patch(struct diff_filepair *p)
{
if (diff_unmodified_pair(p))
return;
if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
(DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
return; /* no tree diffs in patch format */
run_diff(p);
}
int diff_queue_is_empty(void)
{
struct diff_queue_struct *q = &diff_queued_diff;
int i;
for (i = 0; i < q->nr; i++)
if (!diff_unmodified_pair(q->queue[i]))
return 0;
return 1;
}
#if DIFF_DEBUG
void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
{
fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
x, one ? one : "",
s->path,
DIFF_FILE_VALID(s) ? "valid" : "invalid",
s->mode,
s->sha1_valid ? sha1_to_hex(s->sha1) : "");
fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
x, one ? one : "",
s->size, s->xfrm_flags);
}
void diff_debug_filepair(const struct diff_filepair *p, int i)
{
diff_debug_filespec(p->one, i, "one");
diff_debug_filespec(p->two, i, "two");
fprintf(stderr, "score %d, status %c stays %d broken %d\n",
p->score, p->status ? p->status : '?',
p->source_stays, p->broken_pair);
}
void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
{
int i;
if (msg)
fprintf(stderr, "%s\n", msg);
fprintf(stderr, "q->nr = %d\n", q->nr);
for (i = 0; i < q->nr; i++) {
struct diff_filepair *p = q->queue[i];
diff_debug_filepair(p, i);
}
}
#endif
static void diff_resolve_rename_copy(void)
{
int i, j;
struct diff_filepair *p, *pp;
struct diff_queue_struct *q = &diff_queued_diff;
diff_debug_queue("resolve-rename-copy", q);
for (i = 0; i < q->nr; i++) {
p = q->queue[i];
p->status = 0; /* undecided */
if (DIFF_PAIR_UNMERGED(p))
p->status = DIFF_STATUS_UNMERGED;
else if (!DIFF_FILE_VALID(p->one))
p->status = DIFF_STATUS_ADDED;
else if (!DIFF_FILE_VALID(p->two))
p->status = DIFF_STATUS_DELETED;
else if (DIFF_PAIR_TYPE_CHANGED(p))
p->status = DIFF_STATUS_TYPE_CHANGED;
/* from this point on, we are dealing with a pair
* whose both sides are valid and of the same type, i.e.
* either in-place edit or rename/copy edit.
*/
else if (DIFF_PAIR_RENAME(p)) {
if (p->source_stays) {
p->status = DIFF_STATUS_COPIED;
continue;
}
/* See if there is some other filepair that
* copies from the same source as us. If so
* we are a copy. Otherwise we are either a
* copy if the path stays, or a rename if it
* does not, but we already handled "stays" case.
*/
for (j = i + 1; j < q->nr; j++) {
pp = q->queue[j];
if (strcmp(pp->one->path, p->one->path))
continue; /* not us */
if (!DIFF_PAIR_RENAME(pp))
continue; /* not a rename/copy */
/* pp is a rename/copy from the same source */
p->status = DIFF_STATUS_COPIED;
break;
}
if (!p->status)
p->status = DIFF_STATUS_RENAMED;
}
else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
p->one->mode != p->two->mode)
p->status = DIFF_STATUS_MODIFIED;
else {
/* This is a "no-change" entry and should not
* happen anymore, but prepare for broken callers.
*/
error("feeding unmodified %s to diffcore",
p->one->path);
p->status = DIFF_STATUS_UNKNOWN;
}
}
diff_debug_queue("resolve-rename-copy done", q);
}
void diff_flush(struct diff_options *options)
{
struct diff_queue_struct *q = &diff_queued_diff;
int i;
int inter_name_termination = '\t';
int diff_output_format = options->output_format;
int line_termination = options->line_termination;
if (!line_termination)
inter_name_termination = 0;
for (i = 0; i < q->nr; i++) {
struct diff_filepair *p = q->queue[i];
if ((diff_output_format == DIFF_FORMAT_NO_OUTPUT) ||
(p->status == DIFF_STATUS_UNKNOWN))
continue;
if (p->status == 0)
die("internal error in diff-resolve-rename-copy");
switch (diff_output_format) {
case DIFF_FORMAT_PATCH:
diff_flush_patch(p);
break;
case DIFF_FORMAT_RAW:
case DIFF_FORMAT_NAME_STATUS:
diff_flush_raw(p, line_termination,
inter_name_termination,
diff_output_format);
break;
case DIFF_FORMAT_NAME:
diff_flush_name(p, line_termination);
break;
}
diff_free_filepair(q->queue[i]);
}
free(q->queue);
q->queue = NULL;
q->nr = q->alloc = 0;
}
static void diffcore_apply_filter(const char *filter)
{
int i;
struct diff_queue_struct *q = &diff_queued_diff;
struct diff_queue_struct outq;
outq.queue = NULL;
outq.nr = outq.alloc = 0;
if (!filter)
return;
if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
int found;
for (i = found = 0; !found && i < q->nr; i++) {
struct diff_filepair *p = q->queue[i];
if (((p->status == DIFF_STATUS_MODIFIED) &&
((p->score &&
strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
(!p->score &&
strchr(filter, DIFF_STATUS_MODIFIED)))) ||
((p->status != DIFF_STATUS_MODIFIED) &&
strchr(filter, p->status)))
found++;
}
if (found)
return;
/* otherwise we will clear the whole queue
* by copying the empty outq at the end of this
* function, but first clear the current entries
* in the queue.
*/
for (i = 0; i < q->nr; i++)
diff_free_filepair(q->queue[i]);
}
else {
/* Only the matching ones */
for (i = 0; i < q->nr; i++) {
struct diff_filepair *p = q->queue[i];
if (((p->status == DIFF_STATUS_MODIFIED) &&
((p->score &&
strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
(!p->score &&
strchr(filter, DIFF_STATUS_MODIFIED)))) ||
((p->status != DIFF_STATUS_MODIFIED) &&
strchr(filter, p->status)))
diff_q(&outq, p);
else
diff_free_filepair(p);
}
}
free(q->queue);
*q = outq;
}
void diffcore_std(struct diff_options *options)
{
if (options->paths && options->paths[0])
diffcore_pathspec(options->paths);
if (options->break_opt != -1)
diffcore_break(options->break_opt);
if (options->detect_rename)
diffcore_rename(options);
if (options->break_opt != -1)
diffcore_merge_broken();
if (options->pickaxe)
diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
if (options->orderfile)
diffcore_order(options->orderfile);
diff_resolve_rename_copy();
diffcore_apply_filter(options->filter);
}
void diffcore_std_no_resolve(struct diff_options *options)
{
if (options->pickaxe)
diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
if (options->orderfile)
diffcore_order(options->orderfile);
diffcore_apply_filter(options->filter);
}
void diff_addremove(struct diff_options *options,
int addremove, unsigned mode,
const unsigned char *sha1,
const char *base, const char *path)
{
char concatpath[PATH_MAX];
struct diff_filespec *one, *two;
/* This may look odd, but it is a preparation for
* feeding "there are unchanged files which should
* not produce diffs, but when you are doing copy
* detection you would need them, so here they are"
* entries to the diff-core. They will be prefixed
* with something like '=' or '*' (I haven't decided
* which but should not make any difference).
* Feeding the same new and old to diff_change()
* also has the same effect.
* Before the final output happens, they are pruned after
* merged into rename/copy pairs as appropriate.
*/
if (options->reverse_diff)
addremove = (addremove == '+' ? '-' :
addremove == '-' ? '+' : addremove);
if (!path) path = "";
sprintf(concatpath, "%s%s", base, path);
one = alloc_filespec(concatpath);
two = alloc_filespec(concatpath);
if (addremove != '+')
fill_filespec(one, sha1, mode);
if (addremove != '-')
fill_filespec(two, sha1, mode);
diff_queue(&diff_queued_diff, one, two);
}
void diff_change(struct diff_options *options,
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_filespec *one, *two;
if (options->reverse_diff) {
unsigned tmp;
const unsigned char *tmp_c;
tmp = old_mode; old_mode = new_mode; new_mode = tmp;
tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
}
if (!path) path = "";
sprintf(concatpath, "%s%s", base, path);
one = alloc_filespec(concatpath);
two = alloc_filespec(concatpath);
fill_filespec(one, old_sha1, old_mode);
fill_filespec(two, new_sha1, new_mode);
diff_queue(&diff_queued_diff, one, two);
}
void diff_unmerge(struct diff_options *options,
const char *path)
{
struct diff_filespec *one, *two;
one = alloc_filespec(path);
two = alloc_filespec(path);
diff_queue(&diff_queued_diff, one, two);
}