git/diff-no-index.c
Junio C Hamano bfb8376d68 Merge branch 'pw/diff-no-index-from-named-pipes' into maint-2.42
"git diff --no-index -R <(one) <(two)" did not work correctly,
which has been corrected.

* pw/diff-no-index-from-named-pipes:
  diff --no-index: fix -R with stdin
2023-11-02 16:53:18 +09:00

375 lines
9 KiB
C

/*
* "diff --no-index" support
* Copyright (c) 2007 by Johannes Schindelin
* Copyright (c) 2008 by Junio C Hamano
*/
#include "git-compat-util.h"
#include "abspath.h"
#include "color.h"
#include "commit.h"
#include "blob.h"
#include "tag.h"
#include "diff.h"
#include "diffcore.h"
#include "gettext.h"
#include "revision.h"
#include "log-tree.h"
#include "parse-options.h"
#include "string-list.h"
#include "dir.h"
static int read_directory_contents(const char *path, struct string_list *list)
{
DIR *dir;
struct dirent *e;
if (!(dir = opendir(path)))
return error("Could not open directory %s", path);
while ((e = readdir_skip_dot_and_dotdot(dir)))
string_list_insert(list, e->d_name);
closedir(dir);
return 0;
}
/*
* This should be "(standard input)" or something, but it will
* probably expose many more breakages in the way no-index code
* is bolted onto the diff callchain.
*/
static const char file_from_standard_input[] = "-";
/*
* For paths given on the command-line we treat "-" as stdin and named
* pipes and symbolic links to named pipes specially.
*/
enum special {
SPECIAL_NONE,
SPECIAL_STDIN,
SPECIAL_PIPE,
};
static int get_mode(const char *path, int *mode, enum special *special)
{
struct stat st;
if (!path || !strcmp(path, "/dev/null")) {
*mode = 0;
#ifdef GIT_WINDOWS_NATIVE
} else if (!strcasecmp(path, "nul")) {
*mode = 0;
#endif
} else if (path == file_from_standard_input) {
*mode = create_ce_mode(0666);
*special = SPECIAL_STDIN;
} else if (lstat(path, &st)) {
return error("Could not access '%s'", path);
} else {
*mode = st.st_mode;
}
/*
* For paths on the command-line treat named pipes and symbolic
* links that resolve to a named pipe specially.
*/
if (special &&
(S_ISFIFO(*mode) ||
(S_ISLNK(*mode) && !stat(path, &st) && S_ISFIFO(st.st_mode)))) {
*mode = create_ce_mode(0666);
*special = SPECIAL_PIPE;
}
return 0;
}
static void populate_common(struct diff_filespec *s, struct strbuf *buf)
{
size_t size = 0;
s->should_munmap = 0;
s->data = strbuf_detach(buf, &size);
s->size = size;
s->should_free = 1;
s->is_stdin = 1;
}
static void populate_from_pipe(struct diff_filespec *s)
{
struct strbuf buf = STRBUF_INIT;
int fd = xopen(s->path, O_RDONLY);
if (strbuf_read(&buf, fd, 0) < 0)
die_errno("error while reading from '%s'", s->path);
close(fd);
populate_common(s, &buf);
}
static void populate_from_stdin(struct diff_filespec *s)
{
struct strbuf buf = STRBUF_INIT;
if (strbuf_read(&buf, 0, 0) < 0)
die_errno("error while reading from stdin");
populate_common(s, &buf);
}
static struct diff_filespec *noindex_filespec(const char *name, int mode,
enum special special)
{
struct diff_filespec *s;
if (!name)
name = "/dev/null";
s = alloc_filespec(name);
fill_filespec(s, null_oid(), 0, mode);
if (special == SPECIAL_STDIN)
populate_from_stdin(s);
else if (special == SPECIAL_PIPE)
populate_from_pipe(s);
return s;
}
static int queue_diff(struct diff_options *o,
const char *name1, const char *name2, int recursing)
{
int mode1 = 0, mode2 = 0;
enum special special1 = SPECIAL_NONE, special2 = SPECIAL_NONE;
/* Paths can only be special if we're not recursing. */
if (get_mode(name1, &mode1, recursing ? NULL : &special1) ||
get_mode(name2, &mode2, recursing ? NULL : &special2))
return -1;
if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2)) {
struct diff_filespec *d1, *d2;
if (S_ISDIR(mode1)) {
/* 2 is file that is created */
d1 = noindex_filespec(NULL, 0, SPECIAL_NONE);
d2 = noindex_filespec(name2, mode2, special2);
name2 = NULL;
mode2 = 0;
} else {
/* 1 is file that is deleted */
d1 = noindex_filespec(name1, mode1, special1);
d2 = noindex_filespec(NULL, 0, SPECIAL_NONE);
name1 = NULL;
mode1 = 0;
}
/* emit that file */
diff_queue(&diff_queued_diff, d1, d2);
/* and then let the entire directory be created or deleted */
}
if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
struct strbuf buffer1 = STRBUF_INIT;
struct strbuf buffer2 = STRBUF_INIT;
struct string_list p1 = STRING_LIST_INIT_DUP;
struct string_list p2 = STRING_LIST_INIT_DUP;
int i1, i2, ret = 0;
size_t len1 = 0, len2 = 0;
if (name1 && read_directory_contents(name1, &p1))
return -1;
if (name2 && read_directory_contents(name2, &p2)) {
string_list_clear(&p1, 0);
return -1;
}
if (name1) {
strbuf_addstr(&buffer1, name1);
strbuf_complete(&buffer1, '/');
len1 = buffer1.len;
}
if (name2) {
strbuf_addstr(&buffer2, name2);
strbuf_complete(&buffer2, '/');
len2 = buffer2.len;
}
for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
const char *n1, *n2;
int comp;
strbuf_setlen(&buffer1, len1);
strbuf_setlen(&buffer2, len2);
if (i1 == p1.nr)
comp = 1;
else if (i2 == p2.nr)
comp = -1;
else
comp = strcmp(p1.items[i1].string, p2.items[i2].string);
if (comp > 0)
n1 = NULL;
else {
strbuf_addstr(&buffer1, p1.items[i1++].string);
n1 = buffer1.buf;
}
if (comp < 0)
n2 = NULL;
else {
strbuf_addstr(&buffer2, p2.items[i2++].string);
n2 = buffer2.buf;
}
ret = queue_diff(o, n1, n2, 1);
}
string_list_clear(&p1, 0);
string_list_clear(&p2, 0);
strbuf_release(&buffer1);
strbuf_release(&buffer2);
return ret;
} else {
struct diff_filespec *d1, *d2;
if (o->flags.reverse_diff) {
SWAP(mode1, mode2);
SWAP(name1, name2);
SWAP(special1, special2);
}
d1 = noindex_filespec(name1, mode1, special1);
d2 = noindex_filespec(name2, mode2, special2);
diff_queue(&diff_queued_diff, d1, d2);
return 0;
}
}
/* append basename of F to D */
static void append_basename(struct strbuf *path, const char *dir, const char *file)
{
const char *tail = strrchr(file, '/');
strbuf_addstr(path, dir);
while (path->len && path->buf[path->len - 1] == '/')
path->len--;
strbuf_addch(path, '/');
strbuf_addstr(path, tail ? tail + 1 : file);
}
/*
* DWIM "diff D F" into "diff D/F F" and "diff F D" into "diff F D/F"
* Note that we append the basename of F to D/, so "diff a/b/file D"
* becomes "diff a/b/file D/file", not "diff a/b/file D/a/b/file".
*/
static void fixup_paths(const char **path, struct strbuf *replacement)
{
struct stat st;
unsigned int isdir0 = 0, isdir1 = 0;
unsigned int ispipe0 = 0, ispipe1 = 0;
if (path[0] != file_from_standard_input && !stat(path[0], &st)) {
isdir0 = S_ISDIR(st.st_mode);
ispipe0 = S_ISFIFO(st.st_mode);
}
if (path[1] != file_from_standard_input && !stat(path[1], &st)) {
isdir1 = S_ISDIR(st.st_mode);
ispipe1 = S_ISFIFO(st.st_mode);
}
if ((path[0] == file_from_standard_input && isdir1) ||
(isdir0 && path[1] == file_from_standard_input))
die(_("cannot compare stdin to a directory"));
if ((isdir0 && ispipe1) || (ispipe0 && isdir1))
die(_("cannot compare a named pipe to a directory"));
if (isdir0 == isdir1)
return;
if (isdir0) {
append_basename(replacement, path[0], path[1]);
path[0] = replacement->buf;
} else {
append_basename(replacement, path[1], path[0]);
path[1] = replacement->buf;
}
}
static const char * const diff_no_index_usage[] = {
N_("git diff --no-index [<options>] <path> <path>"),
NULL
};
int diff_no_index(struct rev_info *revs,
int implicit_no_index,
int argc, const char **argv)
{
int i, no_index;
int ret = 1;
const char *paths[2];
char *to_free[ARRAY_SIZE(paths)] = { 0 };
struct strbuf replacement = STRBUF_INIT;
const char *prefix = revs->prefix;
struct option no_index_options[] = {
OPT_BOOL_F(0, "no-index", &no_index, "",
PARSE_OPT_NONEG | PARSE_OPT_HIDDEN),
OPT_END(),
};
struct option *options;
options = add_diff_options(no_index_options, &revs->diffopt);
argc = parse_options(argc, argv, revs->prefix, options,
diff_no_index_usage, 0);
if (argc != 2) {
if (implicit_no_index)
warning(_("Not a git repository. Use --no-index to "
"compare two paths outside a working tree"));
usage_with_options(diff_no_index_usage, options);
}
FREE_AND_NULL(options);
for (i = 0; i < 2; i++) {
const char *p = argv[i];
if (!strcmp(p, "-"))
/*
* stdin should be spelled as "-"; if you have
* path that is "-", spell it as "./-".
*/
p = file_from_standard_input;
else if (prefix)
p = to_free[i] = prefix_filename(prefix, p);
paths[i] = p;
}
fixup_paths(paths, &replacement);
revs->diffopt.skip_stat_unmatch = 1;
if (!revs->diffopt.output_format)
revs->diffopt.output_format = DIFF_FORMAT_PATCH;
revs->diffopt.flags.no_index = 1;
revs->diffopt.flags.relative_name = 1;
revs->diffopt.prefix = prefix;
revs->max_count = -2;
diff_setup_done(&revs->diffopt);
setup_diff_pager(&revs->diffopt);
revs->diffopt.flags.exit_with_status = 1;
if (queue_diff(&revs->diffopt, paths[0], paths[1], 0))
goto out;
diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
diffcore_std(&revs->diffopt);
diff_flush(&revs->diffopt);
/*
* The return code for --no-index imitates diff(1):
* 0 = no changes, 1 = changes, else error
*/
ret = diff_result_code(&revs->diffopt);
out:
for (i = 0; i < ARRAY_SIZE(to_free); i++)
free(to_free[i]);
strbuf_release(&replacement);
return ret;
}