git-commit-vandalism/builtin/check-ignore.c
Elijah Newren eceba53214 dir: fix problematic API to avoid memory leaks
The dir structure seemed to have a number of leaks and problems around
it.  First I noticed that parent_hashmap and recursive_hashmap were
being leaked (though Peff noticed and submitted fixes before me).  Then
I noticed in the previous commit that clear_directory() was only taking
responsibility for a subset of fields within dir_struct, despite the
fact that entries[] and ignored[] we allocated internally to dir.c.
That, of course, resulted in many callers either leaking or haphazardly
trying to free these arrays and their contents.

Digging further, I found that despite the pretty clear documentation
near the top of dir.h that folks were supposed to call clear_directory()
when the user no longer needed the dir_struct, there were four callers
that didn't bother doing that at all.  However, two of them clearly
thought about leaks since they had an UNLEAK(dir) directive, which to me
suggests that the method to free the data was too unclear.  I suspect
the non-obviousness of the API and its holes led folks to avoid it,
which then snowballed into further problems with the entries[],
ignored[], parent_hashmap, and recursive_hashmap problems.

Rename clear_directory() to dir_clear() to be more in line with other
data structures in git, and introduce a dir_init() to handle the
suggested memsetting of dir_struct to all zeroes.  I hope that a name
like "dir_clear()" is more clear, and that the presence of dir_init()
will provide a hint to those looking at the code that they need to look
for either a dir_clear() or a dir_free() and lead them to find
dir_clear().

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-18 17:17:31 -07:00

197 lines
5.1 KiB
C

#define USE_THE_INDEX_COMPATIBILITY_MACROS
#include "builtin.h"
#include "cache.h"
#include "config.h"
#include "dir.h"
#include "quote.h"
#include "pathspec.h"
#include "parse-options.h"
#include "submodule.h"
static int quiet, verbose, stdin_paths, show_non_matching, no_index;
static const char * const check_ignore_usage[] = {
"git check-ignore [<options>] <pathname>...",
"git check-ignore [<options>] --stdin",
NULL
};
static int nul_term_line;
static const struct option check_ignore_options[] = {
OPT__QUIET(&quiet, N_("suppress progress reporting")),
OPT__VERBOSE(&verbose, N_("be verbose")),
OPT_GROUP(""),
OPT_BOOL(0, "stdin", &stdin_paths,
N_("read file names from stdin")),
OPT_BOOL('z', NULL, &nul_term_line,
N_("terminate input and output records by a NUL character")),
OPT_BOOL('n', "non-matching", &show_non_matching,
N_("show non-matching input paths")),
OPT_BOOL(0, "no-index", &no_index,
N_("ignore index when checking")),
OPT_END()
};
static void output_pattern(const char *path, struct path_pattern *pattern)
{
char *bang = (pattern && pattern->flags & PATTERN_FLAG_NEGATIVE) ? "!" : "";
char *slash = (pattern && pattern->flags & PATTERN_FLAG_MUSTBEDIR) ? "/" : "";
if (!nul_term_line) {
if (!verbose) {
write_name_quoted(path, stdout, '\n');
} else {
if (pattern) {
quote_c_style(pattern->pl->src, NULL, stdout, 0);
printf(":%d:%s%s%s\t",
pattern->srcpos,
bang, pattern->pattern, slash);
}
else {
printf("::\t");
}
quote_c_style(path, NULL, stdout, 0);
fputc('\n', stdout);
}
} else {
if (!verbose) {
printf("%s%c", path, '\0');
} else {
if (pattern)
printf("%s%c%d%c%s%s%s%c%s%c",
pattern->pl->src, '\0',
pattern->srcpos, '\0',
bang, pattern->pattern, slash, '\0',
path, '\0');
else
printf("%c%c%c%s%c", '\0', '\0', '\0', path, '\0');
}
}
}
static int check_ignore(struct dir_struct *dir,
const char *prefix, int argc, const char **argv)
{
const char *full_path;
char *seen;
int num_ignored = 0, i;
struct path_pattern *pattern;
struct pathspec pathspec;
if (!argc) {
if (!quiet)
fprintf(stderr, "no pathspec given.\n");
return 0;
}
/*
* check-ignore just needs paths. Magic beyond :/ is really
* irrelevant.
*/
parse_pathspec(&pathspec,
PATHSPEC_ALL_MAGIC & ~PATHSPEC_FROMTOP,
PATHSPEC_SYMLINK_LEADING_PATH |
PATHSPEC_KEEP_ORDER,
prefix, argv);
die_path_inside_submodule(&the_index, &pathspec);
/*
* look for pathspecs matching entries in the index, since these
* should not be ignored, in order to be consistent with
* 'git status', 'git add' etc.
*/
seen = find_pathspecs_matching_against_index(&pathspec, &the_index);
for (i = 0; i < pathspec.nr; i++) {
full_path = pathspec.items[i].match;
pattern = NULL;
if (!seen[i]) {
int dtype = DT_UNKNOWN;
pattern = last_matching_pattern(dir, &the_index,
full_path, &dtype);
if (!verbose && pattern &&
pattern->flags & PATTERN_FLAG_NEGATIVE)
pattern = NULL;
}
if (!quiet && (pattern || show_non_matching))
output_pattern(pathspec.items[i].original, pattern);
if (pattern)
num_ignored++;
}
free(seen);
return num_ignored;
}
static int check_ignore_stdin_paths(struct dir_struct *dir, const char *prefix)
{
struct strbuf buf = STRBUF_INIT;
struct strbuf unquoted = STRBUF_INIT;
char *pathspec[2] = { NULL, NULL };
strbuf_getline_fn getline_fn;
int num_ignored = 0;
getline_fn = nul_term_line ? strbuf_getline_nul : strbuf_getline_lf;
while (getline_fn(&buf, stdin) != EOF) {
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);
}
pathspec[0] = buf.buf;
num_ignored += check_ignore(dir, prefix,
1, (const char **)pathspec);
maybe_flush_or_die(stdout, "check-ignore to stdout");
}
strbuf_release(&buf);
strbuf_release(&unquoted);
return num_ignored;
}
int cmd_check_ignore(int argc, const char **argv, const char *prefix)
{
int num_ignored;
struct dir_struct dir;
git_config(git_default_config, NULL);
argc = parse_options(argc, argv, prefix, check_ignore_options,
check_ignore_usage, 0);
if (stdin_paths) {
if (argc > 0)
die(_("cannot specify pathnames with --stdin"));
} else {
if (nul_term_line)
die(_("-z only makes sense with --stdin"));
if (argc == 0)
die(_("no path specified"));
}
if (quiet) {
if (argc > 1)
die(_("--quiet is only valid with a single pathname"));
if (verbose)
die(_("cannot have both --quiet and --verbose"));
}
if (show_non_matching && !verbose)
die(_("--non-matching is only valid with --verbose"));
/* read_cache() is only necessary so we can watch out for submodules. */
if (!no_index && read_cache() < 0)
die(_("index file corrupt"));
dir_init(&dir);
setup_standard_excludes(&dir);
if (stdin_paths) {
num_ignored = check_ignore_stdin_paths(&dir, prefix);
} else {
num_ignored = check_ignore(&dir, prefix, argc, argv);
maybe_flush_or_die(stdout, "ignore to stdout");
}
dir_clear(&dir);
return !num_ignored;
}