Check for NULL commit buffer in cgit_parse_commit()

This can be NULL, so try not to segfault.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/parsing.c b/parsing.c
index b86467a..74a2484 100644
--- a/parsing.c
+++ b/parsing.c
@@ -155,96 +155,99 @@ void cgit_parse_url(const char *url)
 
 	cmd = strchr(url, '/');
 	while (!cgit_repo && cmd) {
 		cmd[0] = '\0';
 		cgit_repo = cgit_get_repoinfo(url);
 		if (cgit_repo == NULL) {
 			cmd[0] = '/';
 			cmd = strchr(cmd + 1, '/');
 			continue;
 		}
 
 		cgit_query_repo = cgit_repo->url;
 		p = strchr(cmd + 1, '/');
 		if (p) {
 			p[0] = '\0';
 			if (p[1])
 				cgit_query_path = xstrdup(p + 1);
 		}
 		cgit_cmd = cgit_get_cmd_index(cmd + 1);
 		cgit_query_page = xstrdup(cmd + 1);
 		return;
 	}
 }
 
 char *substr(const char *head, const char *tail)
 {
 	char *buf;
 
 	buf = xmalloc(tail - head + 1);
 	strncpy(buf, head, tail - head);
 	buf[tail - head] = '\0';
 	return buf;
 }
 
 struct commitinfo *cgit_parse_commit(struct commit *commit)
 {
 	struct commitinfo *ret;
 	char *p = commit->buffer, *t = commit->buffer;
 
 	ret = xmalloc(sizeof(*ret));
 	ret->commit = commit;
 	ret->author = NULL;
 	ret->author_email = NULL;
 	ret->committer = NULL;
 	ret->committer_email = NULL;
 	ret->subject = NULL;
 	ret->msg = NULL;
 
+	if (p == NULL)
+		return ret;
+
 	if (strncmp(p, "tree ", 5))
 		die("Bad commit: %s", sha1_to_hex(commit->object.sha1));
 	else
 		p += 46; // "tree " + hex[40] + "\n"
 
 	while (!strncmp(p, "parent ", 7))
 		p += 48; // "parent " + hex[40] + "\n"
 
 	if (!strncmp(p, "author ", 7)) {
 		p += 7;
 		t = strchr(p, '<') - 1;
 		ret->author = substr(p, t);
 		p = t;
 		t = strchr(t, '>') + 1;
 		ret->author_email = substr(p, t);
 		ret->author_date = atol(++t);
 		p = strchr(t, '\n') + 1;
 	}
 
 	if (!strncmp(p, "committer ", 9)) {
 		p += 9;
 		t = strchr(p, '<') - 1;
 		ret->committer = substr(p, t);
 		p = t;
 		t = strchr(t, '>') + 1;
 		ret->committer_email = substr(p, t);
 		ret->committer_date = atol(++t);
 		p = strchr(t, '\n') + 1;
 	}
 
 	while (*p == '\n')
 		p = strchr(p, '\n') + 1;
 
 	t = strchr(p, '\n');
 	if (t) {
 		if (*t == '\0')
 			ret->subject = strdup("** empty **");
 		else
 			ret->subject = substr(p, t);
 		p = t + 1;
 
 		while (*p == '\n')
 			p = strchr(p, '\n') + 1;
 		ret->msg = p;
 	} else
 		ret->subject = substr(p, p+strlen(p));
 
 	return ret;