git/builtin-grep.c

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/*
* 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>
/*
* 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 *slash, *cp;
if ((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 name directory 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, slash = NULL; cp - match < matchlen; cp++) {
char ch = *cp;
if (ch == '/')
slash = cp;
if (ch == '*' || ch == '[')
break;
}
if (!slash)
slash = match; /* toplevel */
else
slash++;
if (namelen <= slash - match) {
/* Looking at "Documentation/" and
* the pattern says "Documentation/howto/", or
* "Documentation/diff*.txt".
*/
if (!memcmp(match, name, namelen))
return 1;
}
else {
/* Looking at "Documentation/howto/" and
* the pattern says "Documentation/h*".
*/
if (!memcmp(match, name, slash - match))
return 1;
}
}
return 0;
}
struct grep_pat {
struct grep_pat *next;
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 count:1;
unsigned word_regexp:1;
int regflags;
unsigned pre_context;
unsigned post_context;
};
static void add_pattern(struct grep_opt *opt, const char *pat)
{
struct grep_pat *p = xcalloc(1, sizeof(*p));
p->pattern = pat;
*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];
regerror(err, &p->regexp, errbuf, 1024);
regfree(&p->regexp);
die("'%s': %s", 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);
}
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;
const char *hunk_mark = "";
unsigned count = 0;
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) {
regex_t *exp = &p->regexp;
hit = !regexec(exp, bol, ARRAY_SIZE(pmatch),
pmatch, 0);
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]))
continue; /* not a word boundary */
if ((eol-bol) < pmatch[0].rm_eo &&
word_char(bol[pmatch[0].rm_eo]))
continue; /* not a word boundary */
}
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 (hit) {
count++;
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;
}
*eol = ch;
bol = eol + 1;
left--;
lno++;
}
/* 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 grep_cache(struct grep_opt *opt, const char **paths, int cached)
{
int hit = 0;
int nr;
read_cache();
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)
{
unsigned mode;
int len;
int hit = 0;
const char *path;
const unsigned char *sha1;
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->size) {
int pathlen;
sha1 = tree_entry_extract(tree, &path, &mode);
pathlen = strlen(path);
strcpy(path_buf + len, path);
if (S_ISDIR(mode))
/* Match "abc/" against pathspec to
* decide if we want to descend into "abc"
* directory.
*/
strcpy(path_buf + len + pathlen, "/");
if (!pathspec_matches(paths, down))
;
else if (S_ISREG(mode))
hit |= grep_sha1(opt, sha1, path_buf);
else if (S_ISDIR(mode)) {
char type[20];
struct tree_desc sub;
void *data;
data = read_sha1_file(sha1, type, &sub.size);
if (!data)
die("unable to read tree (%s)",
sha1_to_hex(sha1));
sub.buf = data;
hit |= grep_tree(opt, paths, &sub, tree_name, down);
free(data);
}
update_tree_entry(tree);
}
return hit;
}
static int grep_object(struct grep_opt *opt, const char **paths,
struct object *obj, const char *name)
{
if (!strcmp(obj->type, blob_type))
return grep_sha1(opt, obj->sha1, name);
if (!strcmp(obj->type, commit_type) ||
!strcmp(obj->type, tree_type)) {
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", 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 no_more_flags = 0;
int seen_noncommit = 0;
int cached = 0;
struct grep_opt opt;
struct object_list *list, **tail, *object_list = NULL;
const char *prefix = setup_git_directory();
const char **paths = NULL;
memset(&opt, 0, sizeof(opt));
opt.pattern_tail = &opt.pattern_list;
opt.regflags = REG_NEWLINE;
/*
* No point using rev_info, really.
*/
while (1 < argc) {
const char *arg = argv[1];
argc--; argv++;
if (!strcmp("--cached", arg)) {
cached = 1;
continue;
}
if (!strcmp("-i", arg) ||
!strcmp("--ignore-case", arg)) {
opt.regflags |= REG_ICASE;
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("-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("-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("-e", arg)) {
if (1 < argc) {
add_pattern(&opt, argv[1]);
argv++;
argc--;
continue;
}
usage(builtin_grep_usage);
}
if (!strcmp("--", arg)) {
no_more_flags = 1;
continue;
}
/* Either unrecognized option or a single pattern */
if (!no_more_flags && *arg == '-')
usage(builtin_grep_usage);
if (!opt.pattern_list) {
add_pattern(&opt, arg);
break;
}
else {
/* We are looking at the first path or rev;
* it is found at argv[0] after leaving the
* loop.
*/
argc++; argv--;
break;
}
}
if (!opt.pattern_list)
die("no pattern given.");
compile_patterns(&opt);
tail = &object_list;
while (1 < argc) {
struct object *object;
struct object_list *elem;
const char *arg = argv[1];
unsigned char sha1[20];
if (get_sha1(arg, sha1) < 0)
break;
object = parse_object(sha1);
if (!object)
die("bad object %s", arg);
elem = object_list_insert(object, tail);
elem->name = arg;
tail = &elem->next;
argc--; argv++;
}
if (1 < argc)
paths = get_pathspec(prefix, argv + 1);
else if (prefix) {
paths = xcalloc(2, sizeof(const char *));
paths[0] = prefix;
paths[1] = NULL;
}
if (!object_list)
return !grep_cache(&opt, paths, cached);
/*
* Do not walk "grep -e foo master next pu -- Documentation/"
* but do walk "grep -e foo master..next -- Documentation/".
* Ranged request mixed with a blob or tree object, like
* "grep -e foo v1.0.0:Documentation/ master..next"
* so detect that and complain.
*/
for (list = object_list; list; list = list->next) {
struct object *real_obj;
real_obj = deref_tag(list->item, NULL, 0);
if (strcmp(real_obj->type, commit_type))
seen_noncommit = 1;
}
if (cached)
die("both --cached and revisions 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;
}