git-commit-vandalism/builtin/checkout-index.c
Jeff King 517fe807d6 assert NOARG/NONEG behavior of parse-options callbacks
When we define a parse-options callback, the flags we put in the option
struct must match what the callback expects. For example, a callback
which does not handle the "unset" parameter should only be used with
PARSE_OPT_NONEG. But since the callback and the option struct are not
defined next to each other, it's easy to get this wrong (as earlier
patches in this series show).

Fortunately, the compiler can help us here: compiling with
-Wunused-parameters can show us which callbacks ignore their "unset"
parameters (and likewise, ones that ignore "arg" expect to be triggered
with PARSE_OPT_NOARG).

But after we've inspected a callback and determined that all of its
callers use the right flags, what do we do next? We'd like to silence
the compiler warning, but do so in a way that will catch any wrong calls
in the future.

We can do that by actually checking those variables and asserting that
they match our expectations. Because this is such a common pattern,
we'll introduce some helper macros. The resulting messages aren't
as descriptive as we could make them, but the file/line information from
BUG() is enough to identify the problem (and anyway, the point is that
these should never be seen).

Each of the annotated callbacks in this patch triggers
-Wunused-parameters, and was manually inspected to make sure all callers
use the correct options (so none of these BUGs should be triggerable).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-06 12:56:29 +09:00

260 lines
6.6 KiB
C

/*
* Check-out files from the "current cache directory"
*
* Copyright (C) 2005 Linus Torvalds
*
*/
#include "builtin.h"
#include "config.h"
#include "lockfile.h"
#include "quote.h"
#include "cache-tree.h"
#include "parse-options.h"
#define CHECKOUT_ALL 4
static int nul_term_line;
static int checkout_stage; /* default to checkout stage0 */
static int to_tempfile;
static char topath[4][TEMPORARY_FILENAME_LENGTH + 1];
static struct checkout state = CHECKOUT_INIT;
static void write_tempfile_record(const char *name, const char *prefix)
{
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_relative(name, prefix, stdout,
nul_term_line ? '\0' : '\n');
for (i = 0; i < 4; i++) {
topath[i][0] = 0;
}
}
static int checkout_file(const char *name, const char *prefix)
{
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);
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);
}
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);
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 int option_parse_stage(const struct option *opt,
const char *arg, int unset)
{
BUG_ON_OPT_NEG(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;
struct lock_file lock_file = LOCK_INIT;
int all = 0;
int read_from_stdin = 0;
int prefix_length;
int force = 0, quiet = 0, not_new = 0;
int index_opt = 0;
struct option builtin_checkout_index_options[] = {
OPT_BOOL('a', "all", &all,
N_("check out all files in the index")),
OPT__FORCE(&force, N_("force overwrite of existing files"), 0),
OPT__QUIET(&quiet,
N_("no warning for existing files and files not in index")),
OPT_BOOL('n', "no-create", &not_new,
N_("don't checkout new files")),
OPT_BOOL('u', "index", &index_opt,
N_("update stat information in the index file")),
OPT_BOOL('z', NULL, &nul_term_line,
N_("paths are separated with NUL character")),
OPT_BOOL(0, "stdin", &read_from_stdin,
N_("read list of paths from the standard input")),
OPT_BOOL(0, "temp", &to_tempfile,
N_("write the content to temporary files")),
OPT_STRING(0, "prefix", &state.base_dir, N_("string"),
N_("when creating files, prepend <string>")),
{ OPTION_CALLBACK, 0, "stage", NULL, "(1|2|3|all)",
N_("copy out the files from named stage"),
PARSE_OPT_NONEG, 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);
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.istate = &the_index;
state.force = force;
state.quiet = quiet;
state.not_new = not_new;
if (!state.base_dir)
state.base_dir = "";
state.base_dir_len = strlen(state.base_dir);
/*
* when --prefix is specified we do not want to update cache.
*/
if (index_opt && !state.base_dir_len && !to_tempfile) {
state.refresh_cache = 1;
state.istate = &the_index;
hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
}
/* Check out named files first */
for (i = 0; i < argc; i++) {
const char *arg = argv[i];
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);
free(p);
}
if (read_from_stdin) {
struct strbuf buf = STRBUF_INIT;
struct strbuf unquoted = STRBUF_INIT;
strbuf_getline_fn getline_fn;
if (all)
die("git checkout-index: don't mix '--all' and '--stdin'");
getline_fn = nul_term_line ? strbuf_getline_nul : strbuf_getline_lf;
while (getline_fn(&buf, stdin) != EOF) {
char *p;
if (!nul_term_line && buf.buf[0] == '"') {
strbuf_reset(&unquoted);
if (unquote_c_style(&unquoted, buf.buf, NULL))
die("line is badly quoted");
strbuf_swap(&buf, &unquoted);
}
p = prefix_path(prefix, prefix_length, buf.buf);
checkout_file(p, prefix);
free(p);
}
strbuf_release(&unquoted);
strbuf_release(&buf);
}
if (all)
checkout_all(prefix, prefix_length);
if (is_lock_file_locked(&lock_file) &&
write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
die("Unable to write new index file");
return 0;
}