git/builtin-grep.c
Uwe Zeisberger bb9e15a83c Fix possible out-of-bounds array access
If match is "", match[-1] is accessed.  Let pathspec_matches return 1 in that
case indicating that "" matches everything.

Incidently this fixes git-grep'ing in ".".

Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-06-21 02:30:46 -07:00

899 lines
20 KiB
C

/*
* Builtin "git grep"
*
* Copyright (c) 2006 Junio C Hamano
*/
#include "cache.h"
#include "blob.h"
#include "tree.h"
#include "commit.h"
#include "tag.h"
#include "tree-walk.h"
#include "builtin.h"
#include <regex.h>
#include <fnmatch.h>
#include <sys/wait.h>
/*
* git grep pathspecs are somewhat different from diff-tree pathspecs;
* pathname wildcards are allowed.
*/
static int pathspec_matches(const char **paths, const char *name)
{
int namelen, i;
if (!paths || !*paths)
return 1;
namelen = strlen(name);
for (i = 0; paths[i]; i++) {
const char *match = paths[i];
int matchlen = strlen(match);
const char *cp, *meta;
if (!matchlen ||
((matchlen <= namelen) &&
!strncmp(name, match, matchlen) &&
(match[matchlen-1] == '/' ||
name[matchlen] == '\0' || name[matchlen] == '/')))
return 1;
if (!fnmatch(match, name, 0))
return 1;
if (name[namelen-1] != '/')
continue;
/* We are being asked if the directory ("name") is worth
* descending into.
*
* Find the longest leading directory name that does
* not have metacharacter in the pathspec; the name
* we are looking at must overlap with that directory.
*/
for (cp = match, meta = NULL; cp - match < matchlen; cp++) {
char ch = *cp;
if (ch == '*' || ch == '[' || ch == '?') {
meta = cp;
break;
}
}
if (!meta)
meta = cp; /* fully literal */
if (namelen <= meta - match) {
/* Looking at "Documentation/" and
* the pattern says "Documentation/howto/", or
* "Documentation/diff*.txt". The name we
* have should match prefix.
*/
if (!memcmp(match, name, namelen))
return 1;
continue;
}
if (meta - match < namelen) {
/* Looking at "Documentation/howto/" and
* the pattern says "Documentation/h*";
* match up to "Do.../h"; this avoids descending
* into "Documentation/technical/".
*/
if (!memcmp(match, name, meta - match))
return 1;
continue;
}
}
return 0;
}
struct grep_pat {
struct grep_pat *next;
const char *origin;
int no;
const char *pattern;
regex_t regexp;
};
struct grep_opt {
struct grep_pat *pattern_list;
struct grep_pat **pattern_tail;
regex_t regexp;
unsigned linenum:1;
unsigned invert:1;
unsigned name_only:1;
unsigned unmatch_name_only:1;
unsigned count:1;
unsigned word_regexp:1;
unsigned fixed:1;
#define GREP_BINARY_DEFAULT 0
#define GREP_BINARY_NOMATCH 1
#define GREP_BINARY_TEXT 2
unsigned binary:2;
int regflags;
unsigned pre_context;
unsigned post_context;
};
static void add_pattern(struct grep_opt *opt, const char *pat,
const char *origin, int no)
{
struct grep_pat *p = xcalloc(1, sizeof(*p));
p->pattern = pat;
p->origin = origin;
p->no = no;
*opt->pattern_tail = p;
opt->pattern_tail = &p->next;
p->next = NULL;
}
static void compile_patterns(struct grep_opt *opt)
{
struct grep_pat *p;
for (p = opt->pattern_list; p; p = p->next) {
int err = regcomp(&p->regexp, p->pattern, opt->regflags);
if (err) {
char errbuf[1024];
char where[1024];
if (p->no)
sprintf(where, "In '%s' at %d, ",
p->origin, p->no);
else if (p->origin)
sprintf(where, "%s, ", p->origin);
else
where[0] = 0;
regerror(err, &p->regexp, errbuf, 1024);
regfree(&p->regexp);
die("%s'%s': %s", where, p->pattern, errbuf);
}
}
}
static char *end_of_line(char *cp, unsigned long *left)
{
unsigned long l = *left;
while (l && *cp != '\n') {
l--;
cp++;
}
*left = l;
return cp;
}
static int word_char(char ch)
{
return isalnum(ch) || ch == '_';
}
static void show_line(struct grep_opt *opt, const char *bol, const char *eol,
const char *name, unsigned lno, char sign)
{
printf("%s%c", name, sign);
if (opt->linenum)
printf("%d%c", lno, sign);
printf("%.*s\n", (int)(eol-bol), bol);
}
/*
* NEEDSWORK: share code with diff.c
*/
#define FIRST_FEW_BYTES 8000
static int buffer_is_binary(const char *ptr, unsigned long size)
{
if (FIRST_FEW_BYTES < size)
size = FIRST_FEW_BYTES;
if (memchr(ptr, 0, size))
return 1;
return 0;
}
static int fixmatch(const char *pattern, char *line, regmatch_t *match)
{
char *hit = strstr(line, pattern);
if (!hit) {
match->rm_so = match->rm_eo = -1;
return REG_NOMATCH;
}
else {
match->rm_so = hit - line;
match->rm_eo = match->rm_so + strlen(pattern);
return 0;
}
}
static int grep_buffer(struct grep_opt *opt, const char *name,
char *buf, unsigned long size)
{
char *bol = buf;
unsigned long left = size;
unsigned lno = 1;
struct pre_context_line {
char *bol;
char *eol;
} *prev = NULL, *pcl;
unsigned last_hit = 0;
unsigned last_shown = 0;
int binary_match_only = 0;
const char *hunk_mark = "";
unsigned count = 0;
if (buffer_is_binary(buf, size)) {
switch (opt->binary) {
case GREP_BINARY_DEFAULT:
binary_match_only = 1;
break;
case GREP_BINARY_NOMATCH:
return 0; /* Assume unmatch */
break;
default:
break;
}
}
if (opt->pre_context)
prev = xcalloc(opt->pre_context, sizeof(*prev));
if (opt->pre_context || opt->post_context)
hunk_mark = "--\n";
while (left) {
regmatch_t pmatch[10];
char *eol, ch;
int hit = 0;
struct grep_pat *p;
eol = end_of_line(bol, &left);
ch = *eol;
*eol = 0;
for (p = opt->pattern_list; p; p = p->next) {
if (!opt->fixed) {
regex_t *exp = &p->regexp;
hit = !regexec(exp, bol, ARRAY_SIZE(pmatch),
pmatch, 0);
}
else {
hit = !fixmatch(p->pattern, bol, pmatch);
}
if (hit && opt->word_regexp) {
/* Match beginning must be either
* beginning of the line, or at word
* boundary (i.e. the last char must
* not be alnum or underscore).
*/
if ((pmatch[0].rm_so < 0) ||
(eol - bol) <= pmatch[0].rm_so ||
(pmatch[0].rm_eo < 0) ||
(eol - bol) < pmatch[0].rm_eo)
die("regexp returned nonsense");
if (pmatch[0].rm_so != 0 &&
word_char(bol[pmatch[0].rm_so-1]))
hit = 0;
if (pmatch[0].rm_eo != (eol-bol) &&
word_char(bol[pmatch[0].rm_eo]))
hit = 0;
}
if (hit)
break;
}
/* "grep -v -e foo -e bla" should list lines
* that do not have either, so inversion should
* be done outside.
*/
if (opt->invert)
hit = !hit;
if (opt->unmatch_name_only) {
if (hit)
return 0;
goto next_line;
}
if (hit) {
count++;
if (binary_match_only) {
printf("Binary file %s matches\n", name);
return 1;
}
if (opt->name_only) {
printf("%s\n", name);
return 1;
}
/* Hit at this line. If we haven't shown the
* pre-context lines, we would need to show them.
* When asked to do "count", this still show
* the context which is nonsense, but the user
* deserves to get that ;-).
*/
if (opt->pre_context) {
unsigned from;
if (opt->pre_context < lno)
from = lno - opt->pre_context;
else
from = 1;
if (from <= last_shown)
from = last_shown + 1;
if (last_shown && from != last_shown + 1)
printf(hunk_mark);
while (from < lno) {
pcl = &prev[lno-from-1];
show_line(opt, pcl->bol, pcl->eol,
name, from, '-');
from++;
}
last_shown = lno-1;
}
if (last_shown && lno != last_shown + 1)
printf(hunk_mark);
if (!opt->count)
show_line(opt, bol, eol, name, lno, ':');
last_shown = last_hit = lno;
}
else if (last_hit &&
lno <= last_hit + opt->post_context) {
/* If the last hit is within the post context,
* we need to show this line.
*/
if (last_shown && lno != last_shown + 1)
printf(hunk_mark);
show_line(opt, bol, eol, name, lno, '-');
last_shown = lno;
}
if (opt->pre_context) {
memmove(prev+1, prev,
(opt->pre_context-1) * sizeof(*prev));
prev->bol = bol;
prev->eol = eol;
}
next_line:
*eol = ch;
bol = eol + 1;
if (!left)
break;
left--;
lno++;
}
if (opt->unmatch_name_only) {
/* We did not see any hit, so we want to show this */
printf("%s\n", name);
return 1;
}
/* NEEDSWORK:
* The real "grep -c foo *.c" gives many "bar.c:0" lines,
* which feels mostly useless but sometimes useful. Maybe
* make it another option? For now suppress them.
*/
if (opt->count && count)
printf("%s:%u\n", name, count);
return !!last_hit;
}
static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name)
{
unsigned long size;
char *data;
char type[20];
int hit;
data = read_sha1_file(sha1, type, &size);
if (!data) {
error("'%s': unable to read %s", name, sha1_to_hex(sha1));
return 0;
}
hit = grep_buffer(opt, name, data, size);
free(data);
return hit;
}
static int grep_file(struct grep_opt *opt, const char *filename)
{
struct stat st;
int i;
char *data;
if (lstat(filename, &st) < 0) {
err_ret:
if (errno != ENOENT)
error("'%s': %s", filename, strerror(errno));
return 0;
}
if (!st.st_size)
return 0; /* empty file -- no grep hit */
if (!S_ISREG(st.st_mode))
return 0;
i = open(filename, O_RDONLY);
if (i < 0)
goto err_ret;
data = xmalloc(st.st_size + 1);
if (st.st_size != xread(i, data, st.st_size)) {
error("'%s': short read %s", filename, strerror(errno));
close(i);
free(data);
return 0;
}
close(i);
i = grep_buffer(opt, filename, data, st.st_size);
free(data);
return i;
}
static int exec_grep(int argc, const char **argv)
{
pid_t pid;
int status;
argv[argc] = NULL;
pid = fork();
if (pid < 0)
return pid;
if (!pid) {
execvp("grep", (char **) argv);
exit(255);
}
while (waitpid(pid, &status, 0) < 0) {
if (errno == EINTR)
continue;
return -1;
}
if (WIFEXITED(status)) {
if (!WEXITSTATUS(status))
return 1;
return 0;
}
return -1;
}
#define MAXARGS 1000
#define ARGBUF 4096
#define push_arg(a) do { \
if (nr < MAXARGS) argv[nr++] = (a); \
else die("maximum number of args exceeded"); \
} while (0)
static int external_grep(struct grep_opt *opt, const char **paths, int cached)
{
int i, nr, argc, hit, len;
const char *argv[MAXARGS+1];
char randarg[ARGBUF];
char *argptr = randarg;
struct grep_pat *p;
len = nr = 0;
push_arg("grep");
if (opt->fixed)
push_arg("-F");
if (opt->linenum)
push_arg("-n");
if (opt->regflags & REG_EXTENDED)
push_arg("-E");
if (opt->regflags & REG_ICASE)
push_arg("-i");
if (opt->word_regexp)
push_arg("-w");
if (opt->name_only)
push_arg("-l");
if (opt->unmatch_name_only)
push_arg("-L");
if (opt->count)
push_arg("-c");
if (opt->post_context || opt->pre_context) {
if (opt->post_context != opt->pre_context) {
if (opt->pre_context) {
push_arg("-B");
len += snprintf(argptr, sizeof(randarg)-len,
"%u", opt->pre_context);
if (sizeof(randarg) <= len)
die("maximum length of args exceeded");
push_arg(argptr);
argptr += len;
}
if (opt->post_context) {
push_arg("-A");
len += snprintf(argptr, sizeof(randarg)-len,
"%u", opt->post_context);
if (sizeof(randarg) <= len)
die("maximum length of args exceeded");
push_arg(argptr);
argptr += len;
}
}
else {
push_arg("-C");
len += snprintf(argptr, sizeof(randarg)-len,
"%u", opt->post_context);
if (sizeof(randarg) <= len)
die("maximum length of args exceeded");
push_arg(argptr);
argptr += len;
}
}
for (p = opt->pattern_list; p; p = p->next) {
push_arg("-e");
push_arg(p->pattern);
}
/*
* To make sure we get the header printed out when we want it,
* add /dev/null to the paths to grep. This is unnecessary
* (and wrong) with "-l" or "-L", which always print out the
* name anyway.
*
* GNU grep has "-H", but this is portable.
*/
if (!opt->name_only && !opt->unmatch_name_only)
push_arg("/dev/null");
hit = 0;
argc = nr;
for (i = 0; i < active_nr; i++) {
struct cache_entry *ce = active_cache[i];
char *name;
if (ce_stage(ce) || !S_ISREG(ntohl(ce->ce_mode)))
continue;
if (!pathspec_matches(paths, ce->name))
continue;
name = ce->name;
if (name[0] == '-') {
int len = ce_namelen(ce);
name = xmalloc(len + 3);
memcpy(name, "./", 2);
memcpy(name + 2, ce->name, len + 1);
}
argv[argc++] = name;
if (argc < MAXARGS)
continue;
hit += exec_grep(argc, argv);
argc = nr;
}
if (argc > nr)
hit += exec_grep(argc, argv);
return 0;
}
static int grep_cache(struct grep_opt *opt, const char **paths, int cached)
{
int hit = 0;
int nr;
read_cache();
#ifdef __unix__
/*
* Use the external "grep" command for the case where
* we grep through the checked-out files. It tends to
* be a lot more optimized
*/
if (!cached) {
hit = external_grep(opt, paths, cached);
if (hit >= 0)
return hit;
}
#endif
for (nr = 0; nr < active_nr; nr++) {
struct cache_entry *ce = active_cache[nr];
if (ce_stage(ce) || !S_ISREG(ntohl(ce->ce_mode)))
continue;
if (!pathspec_matches(paths, ce->name))
continue;
if (cached)
hit |= grep_sha1(opt, ce->sha1, ce->name);
else
hit |= grep_file(opt, ce->name);
}
return hit;
}
static int grep_tree(struct grep_opt *opt, const char **paths,
struct tree_desc *tree,
const char *tree_name, const char *base)
{
int len;
int hit = 0;
struct name_entry entry;
char *down;
char *path_buf = xmalloc(PATH_MAX + strlen(tree_name) + 100);
if (tree_name[0]) {
int offset = sprintf(path_buf, "%s:", tree_name);
down = path_buf + offset;
strcat(down, base);
}
else {
down = path_buf;
strcpy(down, base);
}
len = strlen(path_buf);
while (tree_entry(tree, &entry)) {
strcpy(path_buf + len, entry.path);
if (S_ISDIR(entry.mode))
/* Match "abc/" against pathspec to
* decide if we want to descend into "abc"
* directory.
*/
strcpy(path_buf + len + entry.pathlen, "/");
if (!pathspec_matches(paths, down))
;
else if (S_ISREG(entry.mode))
hit |= grep_sha1(opt, entry.sha1, path_buf);
else if (S_ISDIR(entry.mode)) {
char type[20];
struct tree_desc sub;
void *data;
data = read_sha1_file(entry.sha1, type, &sub.size);
if (!data)
die("unable to read tree (%s)",
sha1_to_hex(entry.sha1));
sub.buf = data;
hit |= grep_tree(opt, paths, &sub, tree_name, down);
free(data);
}
}
return hit;
}
static int grep_object(struct grep_opt *opt, const char **paths,
struct object *obj, const char *name)
{
if (obj->type == TYPE_BLOB)
return grep_sha1(opt, obj->sha1, name);
if (obj->type == TYPE_COMMIT || obj->type == TYPE_TREE) {
struct tree_desc tree;
void *data;
int hit;
data = read_object_with_reference(obj->sha1, tree_type,
&tree.size, NULL);
if (!data)
die("unable to read tree (%s)", sha1_to_hex(obj->sha1));
tree.buf = data;
hit = grep_tree(opt, paths, &tree, name, "");
free(data);
return hit;
}
die("unable to grep from object of type %s", typename(obj->type));
}
static const char builtin_grep_usage[] =
"git-grep <option>* <rev>* [-e] <pattern> [<path>...]";
int cmd_grep(int argc, const char **argv, char **envp)
{
int hit = 0;
int cached = 0;
int seen_dashdash = 0;
struct grep_opt opt;
struct object_list *list, **tail, *object_list = NULL;
const char *prefix = setup_git_directory();
const char **paths = NULL;
int i;
memset(&opt, 0, sizeof(opt));
opt.pattern_tail = &opt.pattern_list;
opt.regflags = REG_NEWLINE;
/*
* If there is no -- then the paths must exist in the working
* tree. If there is no explicit pattern specified with -e or
* -f, we take the first unrecognized non option to be the
* pattern, but then what follows it must be zero or more
* valid refs up to the -- (if exists), and then existing
* paths. If there is an explicit pattern, then the first
* unrecocnized non option is the beginning of the refs list
* that continues up to the -- (if exists), and then paths.
*/
tail = &object_list;
while (1 < argc) {
const char *arg = argv[1];
argc--; argv++;
if (!strcmp("--cached", arg)) {
cached = 1;
continue;
}
if (!strcmp("-a", arg) ||
!strcmp("--text", arg)) {
opt.binary = GREP_BINARY_TEXT;
continue;
}
if (!strcmp("-i", arg) ||
!strcmp("--ignore-case", arg)) {
opt.regflags |= REG_ICASE;
continue;
}
if (!strcmp("-I", arg)) {
opt.binary = GREP_BINARY_NOMATCH;
continue;
}
if (!strcmp("-v", arg) ||
!strcmp("--invert-match", arg)) {
opt.invert = 1;
continue;
}
if (!strcmp("-E", arg) ||
!strcmp("--extended-regexp", arg)) {
opt.regflags |= REG_EXTENDED;
continue;
}
if (!strcmp("-F", arg) ||
!strcmp("--fixed-strings", arg)) {
opt.fixed = 1;
continue;
}
if (!strcmp("-G", arg) ||
!strcmp("--basic-regexp", arg)) {
opt.regflags &= ~REG_EXTENDED;
continue;
}
if (!strcmp("-n", arg)) {
opt.linenum = 1;
continue;
}
if (!strcmp("-H", arg)) {
/* We always show the pathname, so this
* is a noop.
*/
continue;
}
if (!strcmp("-l", arg) ||
!strcmp("--files-with-matches", arg)) {
opt.name_only = 1;
continue;
}
if (!strcmp("-L", arg) ||
!strcmp("--files-without-match", arg)) {
opt.unmatch_name_only = 1;
continue;
}
if (!strcmp("-c", arg) ||
!strcmp("--count", arg)) {
opt.count = 1;
continue;
}
if (!strcmp("-w", arg) ||
!strcmp("--word-regexp", arg)) {
opt.word_regexp = 1;
continue;
}
if (!strncmp("-A", arg, 2) ||
!strncmp("-B", arg, 2) ||
!strncmp("-C", arg, 2) ||
(arg[0] == '-' && '1' <= arg[1] && arg[1] <= '9')) {
unsigned num;
const char *scan;
switch (arg[1]) {
case 'A': case 'B': case 'C':
if (!arg[2]) {
if (argc <= 1)
usage(builtin_grep_usage);
scan = *++argv;
argc--;
}
else
scan = arg + 2;
break;
default:
scan = arg + 1;
break;
}
if (sscanf(scan, "%u", &num) != 1)
usage(builtin_grep_usage);
switch (arg[1]) {
case 'A':
opt.post_context = num;
break;
default:
case 'C':
opt.post_context = num;
case 'B':
opt.pre_context = num;
break;
}
continue;
}
if (!strcmp("-f", arg)) {
FILE *patterns;
int lno = 0;
char buf[1024];
if (argc <= 1)
usage(builtin_grep_usage);
patterns = fopen(argv[1], "r");
if (!patterns)
die("'%s': %s", argv[1], strerror(errno));
while (fgets(buf, sizeof(buf), patterns)) {
int len = strlen(buf);
if (buf[len-1] == '\n')
buf[len-1] = 0;
/* ignore empty line like grep does */
if (!buf[0])
continue;
add_pattern(&opt, strdup(buf), argv[1], ++lno);
}
fclose(patterns);
argv++;
argc--;
continue;
}
if (!strcmp("-e", arg)) {
if (1 < argc) {
add_pattern(&opt, argv[1], "-e option", 0);
argv++;
argc--;
continue;
}
usage(builtin_grep_usage);
}
if (!strcmp("--", arg))
break;
if (*arg == '-')
usage(builtin_grep_usage);
/* First unrecognized non-option token */
if (!opt.pattern_list) {
add_pattern(&opt, arg, "command line", 0);
break;
}
else {
/* We are looking at the first path or rev;
* it is found at argv[1] after leaving the
* loop.
*/
argc++; argv--;
break;
}
}
if (!opt.pattern_list)
die("no pattern given.");
if ((opt.regflags != REG_NEWLINE) && opt.fixed)
die("cannot mix --fixed-strings and regexp");
if (!opt.fixed)
compile_patterns(&opt);
/* Check revs and then paths */
for (i = 1; i < argc; i++) {
const char *arg = argv[i];
unsigned char sha1[20];
/* Is it a rev? */
if (!get_sha1(arg, sha1)) {
struct object *object = parse_object(sha1);
struct object_list *elem;
if (!object)
die("bad object %s", arg);
elem = object_list_insert(object, tail);
elem->name = arg;
tail = &elem->next;
continue;
}
if (!strcmp(arg, "--")) {
i++;
seen_dashdash = 1;
}
break;
}
/* The rest are paths */
if (!seen_dashdash) {
int j;
for (j = i; j < argc; j++)
verify_filename(prefix, argv[j]);
}
if (i < argc)
paths = get_pathspec(prefix, argv + i);
else if (prefix) {
paths = xcalloc(2, sizeof(const char *));
paths[0] = prefix;
paths[1] = NULL;
}
if (!object_list)
return !grep_cache(&opt, paths, cached);
if (cached)
die("both --cached and trees are given.");
for (list = object_list; list; list = list->next) {
struct object *real_obj;
real_obj = deref_tag(list->item, NULL, 0);
if (grep_object(&opt, paths, real_obj, list->name))
hit = 1;
}
return !hit;
}