git/builtin-grep.c
Andy Whitcroft 93d26e4cb9 short i/o: fix calls to read to use xread or read_in_full
We have a number of badly checked read() calls.  Often we are
expecting read() to read exactly the size we requested or fail, this
fails to handle interrupts or short reads.  Add a read_in_full()
providing those semantics.  Otherwise we at a minimum need to check
for EINTR and EAGAIN, where this is appropriate use xread().

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-01-08 15:44:47 -08:00

719 lines
16 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 "grep.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;
}
static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
{
unsigned long size;
char *data;
char type[20];
char *to_free = NULL;
int hit;
data = read_sha1_file(sha1, type, &size);
if (!data) {
error("'%s': unable to read %s", name, sha1_to_hex(sha1));
return 0;
}
if (opt->relative && opt->prefix_length) {
static char name_buf[PATH_MAX];
char *cp;
int name_len = strlen(name) - opt->prefix_length + 1;
if (!tree_name_len)
name += opt->prefix_length;
else {
if (ARRAY_SIZE(name_buf) <= name_len)
cp = to_free = xmalloc(name_len);
else
cp = name_buf;
memcpy(cp, name, tree_name_len);
strcpy(cp + tree_name_len,
name + tree_name_len + opt->prefix_length);
name = cp;
}
}
hit = grep_buffer(opt, name, data, size);
free(data);
free(to_free);
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 != read_in_full(i, data, st.st_size)) {
error("'%s': short read %s", filename, strerror(errno));
close(i);
free(data);
return 0;
}
close(i);
if (opt->relative && opt->prefix_length)
filename += opt->prefix_length;
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, status;
const char *argv[MAXARGS+1];
char randarg[ARGBUF];
char *argptr = randarg;
struct grep_pat *p;
if (opt->extended || (opt->relative && opt->prefix_length))
return -1;
len = nr = 0;
push_arg("grep");
if (opt->fixed)
push_arg("-F");
if (opt->linenum)
push_arg("-n");
if (!opt->pathname)
push_arg("-h");
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 (!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 && !ce_stage(ce))
continue;
status = exec_grep(argc, argv);
if (0 < status)
hit = 1;
argc = nr;
if (ce_stage(ce)) {
do {
i++;
} while (i < active_nr &&
!strcmp(ce->name, active_cache[i]->name));
i--; /* compensate for loop control */
}
}
if (argc > nr) {
status = exec_grep(argc, argv);
if (0 < status)
hit = 1;
}
return hit;
}
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 (!S_ISREG(ntohl(ce->ce_mode)))
continue;
if (!pathspec_matches(paths, ce->name))
continue;
if (cached) {
if (ce_stage(ce))
continue;
hit |= grep_sha1(opt, ce->sha1, ce->name, 0);
}
else
hit |= grep_file(opt, ce->name);
if (ce_stage(ce)) {
do {
nr++;
} while (nr < active_nr &&
!strcmp(ce->name, active_cache[nr]->name));
nr--; /* compensate for loop control */
}
}
free_grep_patterns(opt);
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;
int tn_len = strlen(tree_name);
char *path_buf = xmalloc(PATH_MAX + tn_len + 100);
if (tn_len) {
tn_len = sprintf(path_buf, "%s:", tree_name);
down = path_buf + tn_len;
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, tn_len);
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 == OBJ_BLOB)
return grep_sha1(opt, obj->sha1, name, 0);
if (obj->type == OBJ_COMMIT || obj->type == OBJ_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>...]";
static const char emsg_invalid_context_len[] =
"%s: invalid context length argument";
static const char emsg_missing_context_len[] =
"missing context length argument";
static const char emsg_missing_argument[] =
"option requires an argument -%s";
int cmd_grep(int argc, const char **argv, const char *prefix)
{
int hit = 0;
int cached = 0;
int seen_dashdash = 0;
struct grep_opt opt;
struct object_array list = { 0, 0, NULL };
const char **paths = NULL;
int i;
memset(&opt, 0, sizeof(opt));
opt.prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
opt.relative = 1;
opt.pathname = 1;
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
* unrecognized non option is the beginning of the refs list
* that continues up to the -- (if exists), and then paths.
*/
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)) {
opt.pathname = 0;
continue;
}
if (!strcmp("-H", arg)) {
opt.pathname = 1;
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)
die(emsg_missing_context_len);
scan = *++argv;
argc--;
}
else
scan = arg + 2;
break;
default:
scan = arg + 1;
break;
}
if (sscanf(scan, "%u", &num) != 1)
die(emsg_invalid_context_len, scan);
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)
die(emsg_missing_argument, arg);
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;
append_grep_pattern(&opt, xstrdup(buf),
argv[1], ++lno,
GREP_PATTERN);
}
fclose(patterns);
argv++;
argc--;
continue;
}
if (!strcmp("--not", arg)) {
append_grep_pattern(&opt, arg, "command line", 0,
GREP_NOT);
continue;
}
if (!strcmp("--and", arg)) {
append_grep_pattern(&opt, arg, "command line", 0,
GREP_AND);
continue;
}
if (!strcmp("--or", arg))
continue; /* no-op */
if (!strcmp("(", arg)) {
append_grep_pattern(&opt, arg, "command line", 0,
GREP_OPEN_PAREN);
continue;
}
if (!strcmp(")", arg)) {
append_grep_pattern(&opt, arg, "command line", 0,
GREP_CLOSE_PAREN);
continue;
}
if (!strcmp("--all-match", arg)) {
opt.all_match = 1;
continue;
}
if (!strcmp("-e", arg)) {
if (1 < argc) {
append_grep_pattern(&opt, argv[1],
"-e option", 0,
GREP_PATTERN);
argv++;
argc--;
continue;
}
die(emsg_missing_argument, arg);
}
if (!strcmp("--full-name", arg)) {
opt.relative = 0;
continue;
}
if (!strcmp("--", arg)) {
/* later processing wants to have this at argv[1] */
argv--;
argc++;
break;
}
if (*arg == '-')
usage(builtin_grep_usage);
/* First unrecognized non-option token */
if (!opt.pattern_list) {
append_grep_pattern(&opt, arg, "command line", 0,
GREP_PATTERN);
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");
compile_grep_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);
if (!object)
die("bad object %s", arg);
add_object_array(object, arg, &list);
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);
if (opt.prefix_length && opt.relative) {
/* Make sure we do not get outside of paths */
for (i = 0; paths[i]; i++)
if (strncmp(prefix, paths[i], opt.prefix_length))
die("git-grep: cannot generate relative filenames containing '..'");
}
}
else if (prefix) {
paths = xcalloc(2, sizeof(const char *));
paths[0] = prefix;
paths[1] = NULL;
}
if (!list.nr)
return !grep_cache(&opt, paths, cached);
if (cached)
die("both --cached and trees are given.");
for (i = 0; i < list.nr; i++) {
struct object *real_obj;
real_obj = deref_tag(list.objects[i].item, NULL, 0);
if (grep_object(&opt, paths, real_obj, list.objects[i].name))
hit = 1;
}
free_grep_patterns(&opt);
return !hit;
}