git/builtin/checkout-index.c
Junio C Hamano af2a651d2e checkout_entry(): clarify the use of topath[] parameter
The said function has this signature:

	extern int checkout_entry(struct cache_entry *ce,
				  const struct checkout *state,
				  char *topath);

At first glance, it might appear that the caller of checkout_entry()
can specify to which path the contents are written out by the last
parameter, and it is tempting to add "const" in front of its type.

In reality, however, topath[] is to point at a buffer to store the
temporary path generated by the callchain originating from this
function, and the temporary path is always short, much shorter than
the buffer prepared by its only caller in builtin/checkout-index.c.

Document the code a bit to clarify so that future callers know how
to use the function better.

Noticed-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-10-24 14:59:39 -07:00

287 lines
7.1 KiB
C

/*
* Check-out files from the "current cache directory"
*
* Copyright (C) 2005 Linus Torvalds
*
*/
#include "builtin.h"
#include "cache.h"
#include "quote.h"
#include "cache-tree.h"
#include "parse-options.h"
#define CHECKOUT_ALL 4
static int line_termination = '\n';
static int checkout_stage; /* default to checkout stage0 */
static int to_tempfile;
static char topath[4][TEMPORARY_FILENAME_LENGTH + 1];
static struct checkout state;
static void write_tempfile_record(const char *name, int prefix_length)
{
int i;
if (CHECKOUT_ALL == checkout_stage) {
for (i = 1; i < 4; i++) {
if (i > 1)
putchar(' ');
if (topath[i][0])
fputs(topath[i], stdout);
else
putchar('.');
}
} else
fputs(topath[checkout_stage], stdout);
putchar('\t');
write_name_quoted(name + prefix_length, stdout, line_termination);
for (i = 0; i < 4; i++) {
topath[i][0] = 0;
}
}
static int checkout_file(const char *name, int prefix_length)
{
int namelen = strlen(name);
int pos = cache_name_pos(name, namelen);
int has_same_name = 0;
int did_checkout = 0;
int errs = 0;
if (pos < 0)
pos = -pos - 1;
while (pos < active_nr) {
struct cache_entry *ce = active_cache[pos];
if (ce_namelen(ce) != namelen ||
memcmp(ce->name, name, namelen))
break;
has_same_name = 1;
pos++;
if (ce_stage(ce) != checkout_stage
&& (CHECKOUT_ALL != checkout_stage || !ce_stage(ce)))
continue;
did_checkout = 1;
if (checkout_entry(ce, &state,
to_tempfile ? topath[ce_stage(ce)] : NULL) < 0)
errs++;
}
if (did_checkout) {
if (to_tempfile)
write_tempfile_record(name, prefix_length);
return errs > 0 ? -1 : 0;
}
if (!state.quiet) {
fprintf(stderr, "git checkout-index: %s ", name);
if (!has_same_name)
fprintf(stderr, "is not in the cache");
else if (checkout_stage)
fprintf(stderr, "does not exist at stage %d",
checkout_stage);
else
fprintf(stderr, "is unmerged");
fputc('\n', stderr);
}
return -1;
}
static void checkout_all(const char *prefix, int prefix_length)
{
int i, errs = 0;
struct cache_entry *last_ce = NULL;
for (i = 0; i < active_nr ; i++) {
struct cache_entry *ce = active_cache[i];
if (ce_stage(ce) != checkout_stage
&& (CHECKOUT_ALL != checkout_stage || !ce_stage(ce)))
continue;
if (prefix && *prefix &&
(ce_namelen(ce) <= prefix_length ||
memcmp(prefix, ce->name, prefix_length)))
continue;
if (last_ce && to_tempfile) {
if (ce_namelen(last_ce) != ce_namelen(ce)
|| memcmp(last_ce->name, ce->name, ce_namelen(ce)))
write_tempfile_record(last_ce->name, prefix_length);
}
if (checkout_entry(ce, &state,
to_tempfile ? topath[ce_stage(ce)] : NULL) < 0)
errs++;
last_ce = ce;
}
if (last_ce && to_tempfile)
write_tempfile_record(last_ce->name, prefix_length);
if (errs)
/* we have already done our error reporting.
* exit with the same code as die().
*/
exit(128);
}
static const char * const builtin_checkout_index_usage[] = {
N_("git checkout-index [options] [--] [<file>...]"),
NULL
};
static struct lock_file lock_file;
static int option_parse_u(const struct option *opt,
const char *arg, int unset)
{
int *newfd = opt->value;
state.refresh_cache = 1;
if (*newfd < 0)
*newfd = hold_locked_index(&lock_file, 1);
return 0;
}
static int option_parse_z(const struct option *opt,
const char *arg, int unset)
{
if (unset)
line_termination = '\n';
else
line_termination = 0;
return 0;
}
static int option_parse_prefix(const struct option *opt,
const char *arg, int unset)
{
state.base_dir = arg;
state.base_dir_len = strlen(arg);
return 0;
}
static int option_parse_stage(const struct option *opt,
const char *arg, int unset)
{
if (!strcmp(arg, "all")) {
to_tempfile = 1;
checkout_stage = CHECKOUT_ALL;
} else {
int ch = arg[0];
if ('1' <= ch && ch <= '3')
checkout_stage = arg[0] - '0';
else
die("stage should be between 1 and 3 or all");
}
return 0;
}
int cmd_checkout_index(int argc, const char **argv, const char *prefix)
{
int i;
int newfd = -1;
int all = 0;
int read_from_stdin = 0;
int prefix_length;
int force = 0, quiet = 0, not_new = 0;
struct option builtin_checkout_index_options[] = {
OPT_BOOLEAN('a', "all", &all,
N_("check out all files in the index")),
OPT__FORCE(&force, N_("force overwrite of existing files")),
OPT__QUIET(&quiet,
N_("no warning for existing files and files not in index")),
OPT_BOOLEAN('n', "no-create", &not_new,
N_("don't checkout new files")),
{ OPTION_CALLBACK, 'u', "index", &newfd, NULL,
N_("update stat information in the index file"),
PARSE_OPT_NOARG, option_parse_u },
{ OPTION_CALLBACK, 'z', NULL, NULL, NULL,
N_("paths are separated with NUL character"),
PARSE_OPT_NOARG, option_parse_z },
OPT_BOOLEAN(0, "stdin", &read_from_stdin,
N_("read list of paths from the standard input")),
OPT_BOOLEAN(0, "temp", &to_tempfile,
N_("write the content to temporary files")),
OPT_CALLBACK(0, "prefix", NULL, N_("string"),
N_("when creating files, prepend <string>"),
option_parse_prefix),
OPT_CALLBACK(0, "stage", NULL, NULL,
N_("copy out the files from named stage"),
option_parse_stage),
OPT_END()
};
if (argc == 2 && !strcmp(argv[1], "-h"))
usage_with_options(builtin_checkout_index_usage,
builtin_checkout_index_options);
git_config(git_default_config, NULL);
state.base_dir = "";
prefix_length = prefix ? strlen(prefix) : 0;
if (read_cache() < 0) {
die("invalid cache");
}
argc = parse_options(argc, argv, prefix, builtin_checkout_index_options,
builtin_checkout_index_usage, 0);
state.force = force;
state.quiet = quiet;
state.not_new = not_new;
if (state.base_dir_len || to_tempfile) {
/* when --prefix is specified we do not
* want to update cache.
*/
if (state.refresh_cache) {
rollback_lock_file(&lock_file);
newfd = -1;
}
state.refresh_cache = 0;
}
/* Check out named files first */
for (i = 0; i < argc; i++) {
const char *arg = argv[i];
const char *p;
if (all)
die("git checkout-index: don't mix '--all' and explicit filenames");
if (read_from_stdin)
die("git checkout-index: don't mix '--stdin' and explicit filenames");
p = prefix_path(prefix, prefix_length, arg);
checkout_file(p, prefix_length);
if (p < arg || p > arg + strlen(arg))
free((char *)p);
}
if (read_from_stdin) {
struct strbuf buf = STRBUF_INIT, nbuf = STRBUF_INIT;
if (all)
die("git checkout-index: don't mix '--all' and '--stdin'");
while (strbuf_getline(&buf, stdin, line_termination) != EOF) {
const char *p;
if (line_termination && buf.buf[0] == '"') {
strbuf_reset(&nbuf);
if (unquote_c_style(&nbuf, buf.buf, NULL))
die("line is badly quoted");
strbuf_swap(&buf, &nbuf);
}
p = prefix_path(prefix, prefix_length, buf.buf);
checkout_file(p, prefix_length);
if (p < buf.buf || p > buf.buf + buf.len)
free((char *)p);
}
strbuf_release(&nbuf);
strbuf_release(&buf);
}
if (all)
checkout_all(prefix, prefix_length);
if (0 <= newfd &&
(write_cache(newfd, active_cache, active_nr) ||
commit_locked_index(&lock_file)))
die("Unable to write new index file");
return 0;
}