Package: reprepro
Version: 4.14.0-1
Severity: normal
Tags: patch
When reprepro crashes, the database lock file is not released, because the lock
file still exists on the system. A patch is attached that changes the locking
system to use fcntl() to lock the database lockfile instead of open with O_EXCL.
With this change, the lock is correctly released in case of the reprepro process
is crashing.
>From 31c4cb8fa6ecddc164e5fe2f51a91360f4fa402d Mon Sep 17 00:00:00 2001
From: Benjamin Drung <benjamin.dr...@profitbricks.com>
Date: Wed, 11 Jun 2014 17:49:59 +0200
Subject: Use fcntl() to lock the database lockfile instead of open with O_EXCL.
The lock required with fcntl() is correctly released in case of the reprepro
process is crashing.
Signed-off-by: Benjamin Drung <benjamin.dr...@profitbricks.com>
---
database.c | 41 +++++++++++++++++++----------------------
1 file changed, 19 insertions(+), 22 deletions(-)
diff --git a/database.c b/database.c
index c6111be..6805b23 100644
--- a/database.c
+++ b/database.c
@@ -90,9 +90,11 @@ static inline char *dbfilename(const char *filename) {
static retvalue database_lock(size_t waitforlock) {
char *lockfile;
+ int e;
int fd;
retvalue r;
size_t tries = 0;
+ struct flock fl = {F_WRLCK, SEEK_SET, 0, 0, getpid()};
assert (!rdb_locked);
rdb_dircreationdepth = 0;
@@ -103,23 +105,29 @@ static retvalue database_lock(size_t waitforlock) {
lockfile = dbfilename("lockfile");
if (FAILEDTOALLOC(lockfile))
return RET_ERROR_OOM;
- fd = open(lockfile, O_WRONLY|O_CREAT|O_EXCL|O_NOFOLLOW|O_NOCTTY,
+ fd = open(lockfile, O_WRONLY|O_CREAT|O_NOFOLLOW|O_NOCTTY,
S_IRUSR|S_IWUSR);
- while (fd < 0) {
- int e = errno;
- if (e == EEXIST) {
+ if (fd == -1) {
+ e = errno;
+ fprintf(stderr,
+"Error %d creating lock file '%s': %s!\n",
+ e, lockfile, strerror(e));
+ free(lockfile);
+ return RET_ERRNO(e);
+ }
+ while (fcntl(fd, F_SETLK, &fl) < 0) {
+ e = errno;
+ if (e == EACCES || e == EAGAIN) {
if (tries < waitforlock && ! interrupted()) {
unsigned int timetosleep = 10;
if (verbose >= 0)
printf(
-"Could not aquire lock: %s already exists!\nWaiting 10 seconds before trying again.\n",
- lockfile);
- while (timetosleep > 0)
+"Could not aquire lock: %s is already locked by process %i!\nWaiting %i seconds before trying again.\n",
+ lockfile, fl.l_pid, timetosleep);
+ while (timetosleep > 0) {
timetosleep = sleep(timetosleep);
+ }
tries++;
- fd = open(lockfile, O_WRONLY|O_CREAT|O_EXCL
- |O_NOFOLLOW|O_NOCTTY,
- S_IRUSR|S_IWUSR);
continue;
}
@@ -131,22 +139,11 @@ static retvalue database_lock(size_t waitforlock) {
} else
fprintf(stderr,
-"Error %d creating lock file '%s': %s!\n",
+"Error %d locking lock file '%s': %s!\n",
e, lockfile, strerror(e));
free(lockfile);
return RET_ERRNO(e);
}
- // TODO: do some more locking of this file to avoid problems
- // with the non-atomity of O_EXCL with nfs-filesystems...
- if (close(fd) != 0) {
- int e = errno;
- fprintf(stderr,
-"(Late) Error %d creating lock file '%s': %s!\n",
- e, lockfile, strerror(e));
- (void)unlink(lockfile);
- free(lockfile);
- return RET_ERRNO(e);
- }
free(lockfile);
rdb_locked = true;
return RET_OK;
--
1.9.1
