Avoid infinite loops in caching layer

Add a global variable, cgit_max_lock_attemps, to avoid the possibility of
infinite loops when failing to acquire a lockfile. This could happen on
broken setups or under crazy server load.

Incidentally, this also fixes a lurking bug in cache_lock() where an
uninitialized returnvalue was used.

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

1 files changed, 1 insertions, 0 deletions

diff --git a/cgit.h b/cgit.h
index 3b0994a..7e4bfef 100644
--- a/cgit.h
+++ b/cgit.h
@@ -1,65 +1,66 @@
 #ifndef CGIT_H
 #define CGIT_H
 
 #include "git.h"
 #include <openssl/sha.h>
 #include <ctype.h>
 #include <sched.h>
 
 typedef void (*configfn)(const char *name, const char *value);
 
 struct cacheitem {
         char *name;
         struct stat st;
         int ttl;
         int fd;
 };
 
 extern char *cgit_root;
 extern char *cgit_root_title;
 extern char *cgit_css;
 extern char *cgit_logo;
 extern char *cgit_logo_link;
 extern char *cgit_virtual_root;
 extern char *cgit_cache_root;
 
+extern int cgit_max_lock_attempts;
 extern int cgit_cache_root_ttl;
 extern int cgit_cache_repo_ttl;
 extern int cgit_cache_dynamic_ttl;
 extern int cgit_cache_static_ttl;
 extern int cgit_cache_max_create_time;
 
 extern char *cgit_repo_name;
 extern char *cgit_repo_desc;
 extern char *cgit_repo_owner;
 
 extern int cgit_query_has_symref;
 extern int cgit_query_has_sha1;
 
 extern char *cgit_querystring;
 extern char *cgit_query_repo;
 extern char *cgit_query_page;
 extern char *cgit_query_head;
 extern char *cgit_query_sha1;
 
 extern int htmlfd;
 
 extern char *fmt(const char *format,...);
 
 extern void html(const char *txt);
 extern void htmlf(const char *format,...);
 extern void html_txt(char *txt);
 extern void html_attr(char *txt);
 extern void html_link_open(char *url, char *title, char *class);
 extern void html_link_close(void);
 
 
 extern int cgit_read_config(const char *filename, configfn fn);
 
 extern void cache_prepare(struct cacheitem *item);
 extern int cache_lock(struct cacheitem *item);
 extern int cache_unlock(struct cacheitem *item);
 extern int cache_exist(struct cacheitem *item);
 extern int cache_expired(struct cacheitem *item);
 
 #endif /* CGIT_H */