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
@@ -139,128 +139,131 @@ int cgit_parse_query(char *txt, configfn fn)
  *   path: any valid path, may contain '/'
  *
  */
 void cgit_parse_url(const char *url)
 {
         char *cmd, *p;
 
         cgit_repo = NULL;
         if (!url || url[0] == '\0')
                 return;
 
         cgit_repo = cgit_get_repoinfo(url);
         if (cgit_repo) {
                 cgit_query_repo = cgit_repo->url;
                 return;
         }
 
         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;
 }
 
 
 struct taginfo *cgit_parse_tag(struct tag *tag)
 {
         void *data;
         enum object_type type;
         unsigned long size;
         char *p, *t;
         struct taginfo *ret;
 
         data = read_sha1_file(tag->object.sha1, &type, &size);
         if (!data || type != OBJ_TAG) {
                 free(data);
                 return 0;
         }