git/diff-tree.c
Junio C Hamano 5098bafb75 Plug diff leaks.
It is a bit embarrassing that it took this long for a fix since the
problem was first reported on Aug 13th.

    Message-ID: <87y876gl1r.wl@mail2.atmark-techno.com>
    From: Yasushi SHOJI <yashi@atmark-techno.com>
    Newsgroups: gmane.comp.version-control.git
    Subject: [patch] possible memory leak in diff.c::diff_free_filepair()
    Date: Sat, 13 Aug 2005 19:58:56 +0900

This time I used valgrind to make sure that it does not overeagerly
discard memory that is still being used.

Signed-off-by: Junio C Hamano <junkio@cox.net>
2005-09-15 16:13:43 -07:00

570 lines
13 KiB
C

#include <ctype.h>
#include "cache.h"
#include "diff.h"
#include "commit.h"
static int show_root_diff = 0;
static int verbose_header = 0;
static int ignore_merges = 1;
static int recursive = 0;
static int show_tree_entry_in_recursive = 0;
static int read_stdin = 0;
static int diff_output_format = DIFF_FORMAT_RAW;
static int diff_line_termination = '\n';
static int detect_rename = 0;
static int find_copies_harder = 0;
static int diff_setup_opt = 0;
static int diff_score_opt = 0;
static const char *pickaxe = NULL;
static int pickaxe_opts = 0;
static int diff_break_opt = -1;
static const char *orderfile = NULL;
static const char *diff_filter = NULL;
static const char *header = NULL;
static const char *header_prefix = "";
static enum cmit_fmt commit_format = CMIT_FMT_RAW;
// What paths are we interested in?
static int nr_paths = 0;
static const char **paths = NULL;
static int *pathlens = NULL;
static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base);
static void update_tree_entry(void **bufp, unsigned long *sizep)
{
void *buf = *bufp;
unsigned long size = *sizep;
int len = strlen(buf) + 1 + 20;
if (size < len)
die("corrupt tree file");
*bufp = buf + len;
*sizep = size - len;
}
static const unsigned char *extract(void *tree, unsigned long size, const char **pathp, unsigned int *modep)
{
int len = strlen(tree)+1;
const unsigned char *sha1 = tree + len;
const char *path = strchr(tree, ' ');
unsigned int mode;
if (!path || size < len + 20 || sscanf(tree, "%o", &mode) != 1)
die("corrupt tree file");
*pathp = path+1;
*modep = DIFF_FILE_CANON_MODE(mode);
return sha1;
}
static char *malloc_base(const char *base, const char *path, int pathlen)
{
int baselen = strlen(base);
char *newbase = xmalloc(baselen + pathlen + 2);
memcpy(newbase, base, baselen);
memcpy(newbase + baselen, path, pathlen);
memcpy(newbase + baselen + pathlen, "/", 2);
return newbase;
}
static void show_file(const char *prefix, void *tree, unsigned long size, const char *base);
static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base);
/* A file entry went away or appeared */
static void show_file(const char *prefix, void *tree, unsigned long size, const char *base)
{
unsigned mode;
const char *path;
const unsigned char *sha1 = extract(tree, size, &path, &mode);
if (recursive && S_ISDIR(mode)) {
char type[20];
unsigned long size;
char *newbase = malloc_base(base, path, strlen(path));
void *tree;
tree = read_sha1_file(sha1, type, &size);
if (!tree || strcmp(type, "tree"))
die("corrupt tree sha %s", sha1_to_hex(sha1));
show_tree(prefix, tree, size, newbase);
free(tree);
free(newbase);
return;
}
diff_addremove(prefix[0], mode, sha1, base, path);
}
static int compare_tree_entry(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
{
unsigned mode1, mode2;
const char *path1, *path2;
const unsigned char *sha1, *sha2;
int cmp, pathlen1, pathlen2;
sha1 = extract(tree1, size1, &path1, &mode1);
sha2 = extract(tree2, size2, &path2, &mode2);
pathlen1 = strlen(path1);
pathlen2 = strlen(path2);
cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2);
if (cmp < 0) {
show_file("-", tree1, size1, base);
return -1;
}
if (cmp > 0) {
show_file("+", tree2, size2, base);
return 1;
}
if (!find_copies_harder && !memcmp(sha1, sha2, 20) && mode1 == mode2)
return 0;
/*
* If the filemode has changed to/from a directory from/to a regular
* file, we need to consider it a remove and an add.
*/
if (S_ISDIR(mode1) != S_ISDIR(mode2)) {
show_file("-", tree1, size1, base);
show_file("+", tree2, size2, base);
return 0;
}
if (recursive && S_ISDIR(mode1)) {
int retval;
char *newbase = malloc_base(base, path1, pathlen1);
if (show_tree_entry_in_recursive)
diff_change(mode1, mode2, sha1, sha2, base, path1);
retval = diff_tree_sha1(sha1, sha2, newbase);
free(newbase);
return retval;
}
diff_change(mode1, mode2, sha1, sha2, base, path1);
return 0;
}
static int interesting(void *tree, unsigned long size, const char *base)
{
const char *path;
unsigned mode;
int i;
int baselen, pathlen;
if (!nr_paths)
return 1;
(void)extract(tree, size, &path, &mode);
pathlen = strlen(path);
baselen = strlen(base);
for (i=0; i < nr_paths; i++) {
const char *match = paths[i];
int matchlen = pathlens[i];
if (baselen >= matchlen) {
/* If it doesn't match, move along... */
if (strncmp(base, match, matchlen))
continue;
/* The base is a subdirectory of a path which was specified. */
return 1;
}
/* Does the base match? */
if (strncmp(base, match, baselen))
continue;
match += baselen;
matchlen -= baselen;
if (pathlen > matchlen)
continue;
if (matchlen > pathlen) {
if (match[pathlen] != '/')
continue;
if (!S_ISDIR(mode))
continue;
}
if (strncmp(path, match, pathlen))
continue;
return 1;
}
return 0; /* No matches */
}
/* A whole sub-tree went away or appeared */
static void show_tree(const char *prefix, void *tree, unsigned long size, const char *base)
{
while (size) {
if (interesting(tree, size, base))
show_file(prefix, tree, size, base);
update_tree_entry(&tree, &size);
}
}
static int diff_tree(void *tree1, unsigned long size1, void *tree2, unsigned long size2, const char *base)
{
while (size1 | size2) {
if (nr_paths && size1 && !interesting(tree1, size1, base)) {
update_tree_entry(&tree1, &size1);
continue;
}
if (nr_paths && size2 && !interesting(tree2, size2, base)) {
update_tree_entry(&tree2, &size2);
continue;
}
if (!size1) {
show_file("+", tree2, size2, base);
update_tree_entry(&tree2, &size2);
continue;
}
if (!size2) {
show_file("-", tree1, size1, base);
update_tree_entry(&tree1, &size1);
continue;
}
switch (compare_tree_entry(tree1, size1, tree2, size2, base)) {
case -1:
update_tree_entry(&tree1, &size1);
continue;
case 0:
update_tree_entry(&tree1, &size1);
/* Fallthrough */
case 1:
update_tree_entry(&tree2, &size2);
continue;
}
die("git-diff-tree: internal error");
}
return 0;
}
static int diff_tree_sha1(const unsigned char *old, const unsigned char *new, const char *base)
{
void *tree1, *tree2;
unsigned long size1, size2;
int retval;
tree1 = read_object_with_reference(old, "tree", &size1, NULL);
if (!tree1)
die("unable to read source tree (%s)", sha1_to_hex(old));
tree2 = read_object_with_reference(new, "tree", &size2, NULL);
if (!tree2)
die("unable to read destination tree (%s)", sha1_to_hex(new));
retval = diff_tree(tree1, size1, tree2, size2, base);
free(tree1);
free(tree2);
return retval;
}
static void call_diff_setup(void)
{
diff_setup(diff_setup_opt);
}
static int call_diff_flush(void)
{
diffcore_std(NULL,
detect_rename, diff_score_opt,
pickaxe, pickaxe_opts,
diff_break_opt,
orderfile,
diff_filter);
if (diff_queue_is_empty()) {
diff_flush(DIFF_FORMAT_NO_OUTPUT, diff_line_termination);
return 0;
}
if (header) {
printf("%s%c", header, diff_line_termination);
header = NULL;
}
diff_flush(diff_output_format, diff_line_termination);
return 1;
}
static int diff_tree_sha1_top(const unsigned char *old,
const unsigned char *new, const char *base)
{
int ret;
call_diff_setup();
ret = diff_tree_sha1(old, new, base);
call_diff_flush();
return ret;
}
static int diff_root_tree(const unsigned char *new, const char *base)
{
int retval;
void *tree;
unsigned long size;
call_diff_setup();
tree = read_object_with_reference(new, "tree", &size, NULL);
if (!tree)
die("unable to read root tree (%s)", sha1_to_hex(new));
retval = diff_tree("", 0, tree, size, base);
free(tree);
call_diff_flush();
return retval;
}
static const char *generate_header(const char *commit, const char *parent, const char *msg, unsigned long len)
{
static char this_header[16384];
int offset;
if (!verbose_header)
return commit;
offset = sprintf(this_header, "%s%s (from %s)\n", header_prefix, commit, parent);
offset += pretty_print_commit(commit_format, msg, len, this_header + offset, sizeof(this_header) - offset);
return this_header;
}
static int diff_tree_commit(const unsigned char *commit, const char *name)
{
unsigned long size, offset;
char *buf = read_object_with_reference(commit, "commit", &size, NULL);
if (!buf)
return -1;
if (!name) {
static char commit_name[60];
strcpy(commit_name, sha1_to_hex(commit));
name = commit_name;
}
/* Root commit? */
if (show_root_diff && memcmp(buf + 46, "parent ", 7)) {
header = generate_header(name, "root", buf, size);
diff_root_tree(commit, "");
}
/* More than one parent? */
if (ignore_merges) {
if (!memcmp(buf + 46 + 48, "parent ", 7))
return 0;
}
offset = 46;
while (offset + 48 < size && !memcmp(buf + offset, "parent ", 7)) {
unsigned char parent[20];
if (get_sha1_hex(buf + offset + 7, parent))
return -1;
header = generate_header(name, sha1_to_hex(parent), buf, size);
diff_tree_sha1_top(parent, commit, "");
if (!header && verbose_header) {
header_prefix = "\ndiff-tree ";
/*
* Don't print multiple merge entries if we
* don't print the diffs.
*/
}
offset += 48;
}
free(buf);
return 0;
}
static int diff_tree_stdin(char *line)
{
int len = strlen(line);
unsigned char commit[20], parent[20];
static char this_header[1000];
if (!len || line[len-1] != '\n')
return -1;
line[len-1] = 0;
if (get_sha1_hex(line, commit))
return -1;
if (isspace(line[40]) && !get_sha1_hex(line+41, parent)) {
line[40] = 0;
line[81] = 0;
sprintf(this_header, "%s (from %s)\n", line, line+41);
header = this_header;
return diff_tree_sha1_top(parent, commit, "");
}
line[40] = 0;
return diff_tree_commit(commit, line);
}
static int count_paths(const char **paths)
{
int i = 0;
while (*paths++)
i++;
return i;
}
static const char diff_tree_usage[] =
"git-diff-tree [--stdin] [-m] [-s] [-v] [--pretty] [-t] "
"[<common diff options>] <tree-ish> <tree-ish>"
COMMON_DIFF_OPTIONS_HELP;
int main(int argc, char **argv)
{
int nr_sha1;
char line[1000];
unsigned char sha1[2][20];
const char *prefix = setup_git_directory();
nr_sha1 = 0;
for (;;) {
const char *arg;
argv++;
argc--;
arg = *argv;
if (!arg)
break;
if (*arg != '-') {
if (nr_sha1 < 2 && !get_sha1(arg, sha1[nr_sha1])) {
nr_sha1++;
continue;
}
break;
}
if (!strcmp(arg, "--")) {
argv++;
argc--;
break;
}
if (!strcmp(arg, "-r")) {
recursive = 1;
continue;
}
if (!strcmp(arg, "-t")) {
recursive = show_tree_entry_in_recursive = 1;
continue;
}
if (!strcmp(arg, "-R")) {
diff_setup_opt |= DIFF_SETUP_REVERSE;
continue;
}
if (!strcmp(arg, "-p") || !strcmp(arg, "-u")) {
diff_output_format = DIFF_FORMAT_PATCH;
recursive = 1;
continue;
}
if (!strncmp(arg, "-S", 2)) {
pickaxe = arg + 2;
continue;
}
if (!strncmp(arg, "-O", 2)) {
orderfile = arg + 2;
continue;
}
if (!strncmp(arg, "--diff-filter=", 14)) {
diff_filter = arg + 14;
continue;
}
if (!strcmp(arg, "--pickaxe-all")) {
pickaxe_opts = DIFF_PICKAXE_ALL;
continue;
}
if (!strncmp(arg, "-M", 2)) {
detect_rename = DIFF_DETECT_RENAME;
if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
usage(diff_tree_usage);
continue;
}
if (!strncmp(arg, "-C", 2)) {
detect_rename = DIFF_DETECT_COPY;
if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
usage(diff_tree_usage);
continue;
}
if (!strncmp(arg, "-B", 2)) {
if ((diff_break_opt = diff_scoreopt_parse(arg)) == -1)
usage(diff_tree_usage);
continue;
}
if (!strcmp(arg, "--find-copies-harder")) {
find_copies_harder = 1;
continue;
}
if (!strcmp(arg, "--name-only")) {
diff_output_format = DIFF_FORMAT_NAME;
continue;
}
if (!strcmp(arg, "-z")) {
diff_line_termination = 0;
continue;
}
if (!strcmp(arg, "-m")) {
ignore_merges = 0;
continue;
}
if (!strcmp(arg, "-s")) {
diff_output_format = DIFF_FORMAT_NO_OUTPUT;
continue;
}
if (!strcmp(arg, "-v")) {
verbose_header = 1;
header_prefix = "diff-tree ";
continue;
}
if (!strncmp(arg, "--pretty", 8)) {
verbose_header = 1;
header_prefix = "diff-tree ";
commit_format = get_commit_format(arg+8);
continue;
}
if (!strcmp(arg, "--stdin")) {
read_stdin = 1;
continue;
}
if (!strcmp(arg, "--root")) {
show_root_diff = 1;
continue;
}
usage(diff_tree_usage);
}
if (find_copies_harder && detect_rename != DIFF_DETECT_COPY)
usage(diff_tree_usage);
paths = get_pathspec(prefix, argv);
if (paths) {
int i;
nr_paths = count_paths(paths);
pathlens = xmalloc(nr_paths * sizeof(int));
for (i=0; i<nr_paths; i++)
pathlens[i] = strlen(paths[i]);
}
switch (nr_sha1) {
case 0:
if (!read_stdin)
usage(diff_tree_usage);
break;
case 1:
diff_tree_commit(sha1[0], NULL);
break;
case 2:
diff_tree_sha1_top(sha1[0], sha1[1], "");
break;
}
if (!read_stdin)
return 0;
if (detect_rename)
diff_setup_opt |= (DIFF_SETUP_USE_SIZE_CACHE |
DIFF_SETUP_USE_CACHE);
while (fgets(line, sizeof(line), stdin))
diff_tree_stdin(line);
return 0;
}