1
0
Fork 0
mirror of https://github.com/git/git.git synced 2024-05-28 19:46:14 +02:00
git/builtin/mv.c
Martin Ågren 610008146e write_locked_index(): add flag to avoid writing unchanged index
We have several callers like

	if (active_cache_changed && write_locked_index(...))
		handle_error();
	rollback_lock_file(...);

where the final rollback is needed because "!active_cache_changed"
shortcuts the if-expression. There are also a few variants of this,
including some if-else constructs that make it more clear when the
explicit rollback is really needed.

Teach `write_locked_index()` to take a new flag SKIP_IF_UNCHANGED and
simplify the callers. Leave the most complicated of the callers (in
builtin/update-index.c) unchanged. Rewriting it to use this new flag
would end up duplicating logic.

We could have made the new flag behave the other way round
("FORCE_WRITE"), but that could break existing users behind their backs.
Let's take the more conservative approach. We can still migrate existing
callers to use our new flag. Later we might even be able to flip the
default, possibly without entirely ignoring the risk to in-flight or
out-of-tree topics.

Suggested-by: Jeff King <peff@peff.net>
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-01 13:28:01 -08:00

302 lines
8.4 KiB
C

/*
* "git mv" builtin command
*
* Copyright (C) 2006 Johannes Schindelin
*/
#include "builtin.h"
#include "config.h"
#include "pathspec.h"
#include "lockfile.h"
#include "dir.h"
#include "cache-tree.h"
#include "string-list.h"
#include "parse-options.h"
#include "submodule.h"
static const char * const builtin_mv_usage[] = {
N_("git mv [<options>] <source>... <destination>"),
NULL
};
#define DUP_BASENAME 1
#define KEEP_TRAILING_SLASH 2
static const char **internal_prefix_pathspec(const char *prefix,
const char **pathspec,
int count, unsigned flags)
{
int i;
const char **result;
int prefixlen = prefix ? strlen(prefix) : 0;
ALLOC_ARRAY(result, count + 1);
/* Create an intermediate copy of the pathspec based on the flags */
for (i = 0; i < count; i++) {
int length = strlen(pathspec[i]);
int to_copy = length;
char *it;
while (!(flags & KEEP_TRAILING_SLASH) &&
to_copy > 0 && is_dir_sep(pathspec[i][to_copy - 1]))
to_copy--;
it = xmemdupz(pathspec[i], to_copy);
if (flags & DUP_BASENAME) {
result[i] = xstrdup(basename(it));
free(it);
} else {
result[i] = it;
}
}
result[count] = NULL;
/* Prefix the pathspec and free the old intermediate strings */
for (i = 0; i < count; i++) {
const char *match = prefix_path(prefix, prefixlen, result[i]);
free((char *) result[i]);
result[i] = match;
}
return result;
}
static const char *add_slash(const char *path)
{
size_t len = strlen(path);
if (path[len - 1] != '/') {
char *with_slash = xmalloc(st_add(len, 2));
memcpy(with_slash, path, len);
with_slash[len++] = '/';
with_slash[len] = 0;
return with_slash;
}
return path;
}
static struct lock_file lock_file;
#define SUBMODULE_WITH_GITDIR ((const char *)1)
static void prepare_move_submodule(const char *src, int first,
const char **submodule_gitfile)
{
struct strbuf submodule_dotgit = STRBUF_INIT;
if (!S_ISGITLINK(active_cache[first]->ce_mode))
die(_("Directory %s is in index and no submodule?"), src);
if (!is_staging_gitmodules_ok(&the_index))
die(_("Please stage your changes to .gitmodules or stash them to proceed"));
strbuf_addf(&submodule_dotgit, "%s/.git", src);
*submodule_gitfile = read_gitfile(submodule_dotgit.buf);
if (*submodule_gitfile)
*submodule_gitfile = xstrdup(*submodule_gitfile);
else
*submodule_gitfile = SUBMODULE_WITH_GITDIR;
strbuf_release(&submodule_dotgit);
}
static int index_range_of_same_dir(const char *src, int length,
int *first_p, int *last_p)
{
const char *src_w_slash = add_slash(src);
int first, last, len_w_slash = length + 1;
first = cache_name_pos(src_w_slash, len_w_slash);
if (first >= 0)
die(_("%.*s is in index"), len_w_slash, src_w_slash);
first = -1 - first;
for (last = first; last < active_nr; last++) {
const char *path = active_cache[last]->name;
if (strncmp(path, src_w_slash, len_w_slash))
break;
}
if (src_w_slash != src)
free((char *)src_w_slash);
*first_p = first;
*last_p = last;
return last - first;
}
int cmd_mv(int argc, const char **argv, const char *prefix)
{
int i, flags, gitmodules_modified = 0;
int verbose = 0, show_only = 0, force = 0, ignore_errors = 0;
struct option builtin_mv_options[] = {
OPT__VERBOSE(&verbose, N_("be verbose")),
OPT__DRY_RUN(&show_only, N_("dry run")),
OPT__FORCE(&force, N_("force move/rename even if target exists")),
OPT_BOOL('k', NULL, &ignore_errors, N_("skip move/rename errors")),
OPT_END(),
};
const char **source, **destination, **dest_path, **submodule_gitfile;
enum update_mode { BOTH = 0, WORKING_DIRECTORY, INDEX } *modes;
struct stat st;
struct string_list src_for_dst = STRING_LIST_INIT_NODUP;
git_config(git_default_config, NULL);
argc = parse_options(argc, argv, prefix, builtin_mv_options,
builtin_mv_usage, 0);
if (--argc < 1)
usage_with_options(builtin_mv_usage, builtin_mv_options);
hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
if (read_cache() < 0)
die(_("index file corrupt"));
source = internal_prefix_pathspec(prefix, argv, argc, 0);
modes = xcalloc(argc, sizeof(enum update_mode));
/*
* Keep trailing slash, needed to let
* "git mv file no-such-dir/" error out, except in the case
* "git mv directory no-such-dir/".
*/
flags = KEEP_TRAILING_SLASH;
if (argc == 1 && is_directory(argv[0]) && !is_directory(argv[1]))
flags = 0;
dest_path = internal_prefix_pathspec(prefix, argv + argc, 1, flags);
submodule_gitfile = xcalloc(argc, sizeof(char *));
if (dest_path[0][0] == '\0')
/* special case: "." was normalized to "" */
destination = internal_prefix_pathspec(dest_path[0], argv, argc, DUP_BASENAME);
else if (!lstat(dest_path[0], &st) &&
S_ISDIR(st.st_mode)) {
dest_path[0] = add_slash(dest_path[0]);
destination = internal_prefix_pathspec(dest_path[0], argv, argc, DUP_BASENAME);
} else {
if (argc != 1)
die(_("destination '%s' is not a directory"), dest_path[0]);
destination = dest_path;
}
/* Checking */
for (i = 0; i < argc; i++) {
const char *src = source[i], *dst = destination[i];
int length, src_is_dir;
const char *bad = NULL;
if (show_only)
printf(_("Checking rename of '%s' to '%s'\n"), src, dst);
length = strlen(src);
if (lstat(src, &st) < 0)
bad = _("bad source");
else if (!strncmp(src, dst, length) &&
(dst[length] == 0 || dst[length] == '/')) {
bad = _("can not move directory into itself");
} else if ((src_is_dir = S_ISDIR(st.st_mode))
&& lstat(dst, &st) == 0)
bad = _("cannot move directory over file");
else if (src_is_dir) {
int first = cache_name_pos(src, length), last;
if (first >= 0)
prepare_move_submodule(src, first,
submodule_gitfile + i);
else if (index_range_of_same_dir(src, length,
&first, &last) < 1)
bad = _("source directory is empty");
else { /* last - first >= 1 */
int j, dst_len, n;
modes[i] = WORKING_DIRECTORY;
n = argc + last - first;
REALLOC_ARRAY(source, n);
REALLOC_ARRAY(destination, n);
REALLOC_ARRAY(modes, n);
REALLOC_ARRAY(submodule_gitfile, n);
dst = add_slash(dst);
dst_len = strlen(dst);
for (j = 0; j < last - first; j++) {
const char *path = active_cache[first + j]->name;
source[argc + j] = path;
destination[argc + j] =
prefix_path(dst, dst_len, path + length + 1);
modes[argc + j] = INDEX;
submodule_gitfile[argc + j] = NULL;
}
argc += last - first;
}
} else if (cache_name_pos(src, length) < 0)
bad = _("not under version control");
else if (lstat(dst, &st) == 0 &&
(!ignore_case || strcasecmp(src, dst))) {
bad = _("destination exists");
if (force) {
/*
* only files can overwrite each other:
* check both source and destination
*/
if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) {
if (verbose)
warning(_("overwriting '%s'"), dst);
bad = NULL;
} else
bad = _("Cannot overwrite");
}
} else if (string_list_has_string(&src_for_dst, dst))
bad = _("multiple sources for the same target");
else if (is_dir_sep(dst[strlen(dst) - 1]))
bad = _("destination directory does not exist");
else
string_list_insert(&src_for_dst, dst);
if (!bad)
continue;
if (!ignore_errors)
die(_("%s, source=%s, destination=%s"),
bad, src, dst);
if (--argc > 0) {
int n = argc - i;
memmove(source + i, source + i + 1,
n * sizeof(char *));
memmove(destination + i, destination + i + 1,
n * sizeof(char *));
memmove(modes + i, modes + i + 1,
n * sizeof(enum update_mode));
memmove(submodule_gitfile + i, submodule_gitfile + i + 1,
n * sizeof(char *));
i--;
}
}
for (i = 0; i < argc; i++) {
const char *src = source[i], *dst = destination[i];
enum update_mode mode = modes[i];
int pos;
if (show_only || verbose)
printf(_("Renaming %s to %s\n"), src, dst);
if (show_only)
continue;
if (mode != INDEX && rename(src, dst) < 0) {
if (ignore_errors)
continue;
die_errno(_("renaming '%s' failed"), src);
}
if (submodule_gitfile[i]) {
if (submodule_gitfile[i] != SUBMODULE_WITH_GITDIR)
connect_work_tree_and_git_dir(dst, submodule_gitfile[i]);
if (!update_path_in_gitmodules(src, dst))
gitmodules_modified = 1;
}
if (mode == WORKING_DIRECTORY)
continue;
pos = cache_name_pos(src, strlen(src));
assert(pos >= 0);
if (!show_only)
rename_cache_entry_at(pos, dst);
}
if (gitmodules_modified)
stage_updated_gitmodules(&the_index);
if (write_locked_index(&the_index, &lock_file,
COMMIT_LOCK | SKIP_IF_UNCHANGED))
die(_("Unable to write new index file"));
return 0;
}