cgitsb/ui-diff.c
Lukas Fleischer 9afc883297 Avoid null pointer dereference in cgit_print_diff().
When calling cgit_print_diff() with a bad new_rev and a NULL old_rev,
checking for new_rev's parent commit will result in a null pointer
dereference. Returning on an invalid commit before dereferencing fixes
this. Spotted with clang-analyzer.

Signed-off-by: Lukas Fleischer <cgit@cryptocrack.de>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
2011-05-23 22:58:35 +02:00

391 lignes
10 KiB
C

/* ui-diff.c: show diff between two blobs
*
* Copyright (C) 2006 Lars Hjemli
*
* Licensed under GNU General Public License v2
* (see COPYING for full license text)
*/
#include "cgit.h"
#include "html.h"
#include "ui-shared.h"
#include "ui-ssdiff.h"
unsigned char old_rev_sha1[20];
unsigned char new_rev_sha1[20];
static int files, slots;
static int total_adds, total_rems, max_changes;
static int lines_added, lines_removed;
static struct fileinfo {
char status;
unsigned char old_sha1[20];
unsigned char new_sha1[20];
unsigned short old_mode;
unsigned short new_mode;
char *old_path;
char *new_path;
unsigned int added;
unsigned int removed;
unsigned long old_size;
unsigned long new_size;
int binary:1;
} *items;
static int use_ssdiff = 0;
static struct diff_filepair *current_filepair;
struct diff_filespec *cgit_get_current_old_file(void)
{
return current_filepair->one;
}
struct diff_filespec *cgit_get_current_new_file(void)
{
return current_filepair->two;
}
static void print_fileinfo(struct fileinfo *info)
{
char *class;
switch (info->status) {
case DIFF_STATUS_ADDED:
class = "add";
break;
case DIFF_STATUS_COPIED:
class = "cpy";
break;
case DIFF_STATUS_DELETED:
class = "del";
break;
case DIFF_STATUS_MODIFIED:
class = "upd";
break;
case DIFF_STATUS_RENAMED:
class = "mov";
break;
case DIFF_STATUS_TYPE_CHANGED:
class = "typ";
break;
case DIFF_STATUS_UNKNOWN:
class = "unk";
break;
case DIFF_STATUS_UNMERGED:
class = "stg";
break;
default:
die("bug: unhandled diff status %c", info->status);
}
html("<tr>");
htmlf("<td class='mode'>");
if (is_null_sha1(info->new_sha1)) {
cgit_print_filemode(info->old_mode);
} else {
cgit_print_filemode(info->new_mode);
}
if (info->old_mode != info->new_mode &&
!is_null_sha1(info->old_sha1) &&
!is_null_sha1(info->new_sha1)) {
html("<span class='modechange'>[");
cgit_print_filemode(info->old_mode);
html("]</span>");
}
htmlf("</td><td class='%s'>", class);
cgit_diff_link(info->new_path, NULL, NULL, ctx.qry.head, ctx.qry.sha1,
ctx.qry.sha2, info->new_path, 0);
if (info->status == DIFF_STATUS_COPIED || info->status == DIFF_STATUS_RENAMED)
htmlf(" (%s from %s)",
info->status == DIFF_STATUS_COPIED ? "copied" : "renamed",
info->old_path);
html("</td><td class='right'>");
if (info->binary) {
htmlf("bin</td><td class='graph'>%ld -> %ld bytes",
info->old_size, info->new_size);
return;
}
htmlf("%d", info->added + info->removed);
html("</td><td class='graph'>");
htmlf("<table summary='file diffstat' width='%d%%'><tr>", (max_changes > 100 ? 100 : max_changes));
htmlf("<td class='add' style='width: %.1f%%;'/>",
info->added * 100.0 / max_changes);
htmlf("<td class='rem' style='width: %.1f%%;'/>",
info->removed * 100.0 / max_changes);
htmlf("<td class='none' style='width: %.1f%%;'/>",
(max_changes - info->removed - info->added) * 100.0 / max_changes);
html("</tr></table></td></tr>\n");
}
static void count_diff_lines(char *line, int len)
{
if (line && (len > 0)) {
if (line[0] == '+')
lines_added++;
else if (line[0] == '-')
lines_removed++;
}
}
static void inspect_filepair(struct diff_filepair *pair)
{
int binary = 0;
unsigned long old_size = 0;
unsigned long new_size = 0;
files++;
lines_added = 0;
lines_removed = 0;
cgit_diff_files(pair->one->sha1, pair->two->sha1, &old_size, &new_size,
&binary, 0, ctx.qry.ignorews, count_diff_lines);
if (files >= slots) {
if (slots == 0)
slots = 4;
else
slots = slots * 2;
items = xrealloc(items, slots * sizeof(struct fileinfo));
}
items[files-1].status = pair->status;
hashcpy(items[files-1].old_sha1, pair->one->sha1);
hashcpy(items[files-1].new_sha1, pair->two->sha1);
items[files-1].old_mode = pair->one->mode;
items[files-1].new_mode = pair->two->mode;
items[files-1].old_path = xstrdup(pair->one->path);
items[files-1].new_path = xstrdup(pair->two->path);
items[files-1].added = lines_added;
items[files-1].removed = lines_removed;
items[files-1].old_size = old_size;
items[files-1].new_size = new_size;
items[files-1].binary = binary;
if (lines_added + lines_removed > max_changes)
max_changes = lines_added + lines_removed;
total_adds += lines_added;
total_rems += lines_removed;
}
void cgit_print_diffstat(const unsigned char *old_sha1,
const unsigned char *new_sha1, const char *prefix)
{
int i, save_context = ctx.qry.context;
html("<div class='diffstat-header'>");
cgit_diff_link("Diffstat", NULL, NULL, ctx.qry.head, ctx.qry.sha1,
ctx.qry.sha2, NULL, 0);
if (prefix) {
html(" (limited to '");
html_txt(prefix);
html("')");
}
html(" (");
ctx.qry.context = (save_context > 0 ? save_context : 3) << 1;
cgit_self_link("more", NULL, NULL, &ctx);
html("/");
ctx.qry.context = (save_context > 3 ? save_context : 3) >> 1;
cgit_self_link("less", NULL, NULL, &ctx);
ctx.qry.context = save_context;
html(" context)");
html(" (");
ctx.qry.ignorews = (ctx.qry.ignorews + 1) % 2;
cgit_self_link(ctx.qry.ignorews ? "ignore" : "show", NULL, NULL, &ctx);
ctx.qry.ignorews = (ctx.qry.ignorews + 1) % 2;
html(" whitespace changes)");
html("</div>");
html("<table summary='diffstat' class='diffstat'>");
max_changes = 0;
cgit_diff_tree(old_sha1, new_sha1, inspect_filepair, prefix,
ctx.qry.ignorews);
for(i = 0; i<files; i++)
print_fileinfo(&items[i]);
html("</table>");
html("<div class='diffstat-summary'>");
htmlf("%d files changed, %d insertions, %d deletions",
files, total_adds, total_rems);
html("</div>");
}
/*
* print a single line returned from xdiff
*/
static void print_line(char *line, int len)
{
char *class = "ctx";
char c = line[len-1];
if (line[0] == '+')
class = "add";
else if (line[0] == '-')
class = "del";
else if (line[0] == '@')
class = "hunk";
htmlf("<div class='%s'>", class);
line[len-1] = '\0';
html_txt(line);
html("</div>");
line[len-1] = c;
}
static void header(unsigned char *sha1, char *path1, int mode1,
unsigned char *sha2, char *path2, int mode2)
{
char *abbrev1, *abbrev2;
int subproject;
subproject = (S_ISGITLINK(mode1) || S_ISGITLINK(mode2));
html("<div class='head'>");
html("diff --git a/");
html_txt(path1);
html(" b/");
html_txt(path2);
if (is_null_sha1(sha1))
path1 = "dev/null";
if (is_null_sha1(sha2))
path2 = "dev/null";
if (mode1 == 0)
htmlf("<br/>new file mode %.6o", mode2);
if (mode2 == 0)
htmlf("<br/>deleted file mode %.6o", mode1);
if (!subproject) {
abbrev1 = xstrdup(find_unique_abbrev(sha1, DEFAULT_ABBREV));
abbrev2 = xstrdup(find_unique_abbrev(sha2, DEFAULT_ABBREV));
htmlf("<br/>index %s..%s", abbrev1, abbrev2);
free(abbrev1);
free(abbrev2);
if (mode1 != 0 && mode2 != 0) {
htmlf(" %.6o", mode1);
if (mode2 != mode1)
htmlf("..%.6o", mode2);
}
html("<br/>--- a/");
if (mode1 != 0)
cgit_tree_link(path1, NULL, NULL, ctx.qry.head,
sha1_to_hex(old_rev_sha1), path1);
else
html_txt(path1);
html("<br/>+++ b/");
if (mode2 != 0)
cgit_tree_link(path2, NULL, NULL, ctx.qry.head,
sha1_to_hex(new_rev_sha1), path2);
else
html_txt(path2);
}
html("</div>");
}
static void print_ssdiff_link()
{
if (!strcmp(ctx.qry.page, "diff")) {
if (use_ssdiff)
cgit_diff_link("Unidiff", NULL, NULL, ctx.qry.head,
ctx.qry.sha1, ctx.qry.sha2, ctx.qry.path, 1);
else
cgit_diff_link("Side-by-side diff", NULL, NULL,
ctx.qry.head, ctx.qry.sha1,
ctx.qry.sha2, ctx.qry.path, 1);
}
}
static void filepair_cb(struct diff_filepair *pair)
{
unsigned long old_size = 0;
unsigned long new_size = 0;
int binary = 0;
linediff_fn print_line_fn = print_line;
current_filepair = pair;
if (use_ssdiff) {
cgit_ssdiff_header_begin();
print_line_fn = cgit_ssdiff_line_cb;
}
header(pair->one->sha1, pair->one->path, pair->one->mode,
pair->two->sha1, pair->two->path, pair->two->mode);
if (use_ssdiff)
cgit_ssdiff_header_end();
if (S_ISGITLINK(pair->one->mode) || S_ISGITLINK(pair->two->mode)) {
if (S_ISGITLINK(pair->one->mode))
print_line_fn(fmt("-Subproject %s", sha1_to_hex(pair->one->sha1)), 52);
if (S_ISGITLINK(pair->two->mode))
print_line_fn(fmt("+Subproject %s", sha1_to_hex(pair->two->sha1)), 52);
if (use_ssdiff)
cgit_ssdiff_footer();
return;
}
if (cgit_diff_files(pair->one->sha1, pair->two->sha1, &old_size,
&new_size, &binary, ctx.qry.context,
ctx.qry.ignorews, print_line_fn))
cgit_print_error("Error running diff");
if (binary) {
if (use_ssdiff)
html("<tr><td colspan='4'>Binary files differ</td></tr>");
else
html("Binary files differ");
}
if (use_ssdiff)
cgit_ssdiff_footer();
}
void cgit_print_diff(const char *new_rev, const char *old_rev, const char *prefix)
{
enum object_type type;
unsigned long size;
struct commit *commit, *commit2;
if (!new_rev)
new_rev = ctx.qry.head;
get_sha1(new_rev, new_rev_sha1);
type = sha1_object_info(new_rev_sha1, &size);
if (type == OBJ_BAD) {
cgit_print_error(fmt("Bad object name: %s", new_rev));
return;
}
commit = lookup_commit_reference(new_rev_sha1);
if (!commit || parse_commit(commit)) {
cgit_print_error(fmt("Bad commit: %s", sha1_to_hex(new_rev_sha1)));
return;
}
if (old_rev)
get_sha1(old_rev, old_rev_sha1);
else if (commit->parents && commit->parents->item)
hashcpy(old_rev_sha1, commit->parents->item->object.sha1);
else
hashclr(old_rev_sha1);
if (!is_null_sha1(old_rev_sha1)) {
type = sha1_object_info(old_rev_sha1, &size);
if (type == OBJ_BAD) {
cgit_print_error(fmt("Bad object name: %s", sha1_to_hex(old_rev_sha1)));
return;
}
commit2 = lookup_commit_reference(old_rev_sha1);
if (!commit2 || parse_commit(commit2)) {
cgit_print_error(fmt("Bad commit: %s", sha1_to_hex(old_rev_sha1)));
return;
}
}
if ((ctx.qry.ssdiff && !ctx.cfg.ssdiff) || (!ctx.qry.ssdiff && ctx.cfg.ssdiff))
use_ssdiff = 1;
print_ssdiff_link();
cgit_print_diffstat(old_rev_sha1, new_rev_sha1, prefix);
if (use_ssdiff) {
html("<table summary='ssdiff' class='ssdiff'>");
} else {
html("<table summary='diff' class='diff'>");
html("<tr><td>");
}
cgit_diff_tree(old_rev_sha1, new_rev_sha1, filepair_cb, prefix,
ctx.qry.ignorews);
if (!use_ssdiff)
html("</td></tr>");
html("</table>");
}