diff options
| -rw-r--r-- | sys/src/cmd/lock.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/sys/src/cmd/lock.c b/sys/src/cmd/lock.c index 1b2197f0d..27210259a 100644 --- a/sys/src/cmd/lock.c +++ b/sys/src/cmd/lock.c @@ -41,24 +41,28 @@ waitfor(int pid) static int openlock(char *lock) { - int lckfd; + int lckfd, didwstat = 0; Dir *dir; - if (lockwait) - while ((lckfd = open(lock, ORDWR)) < 0) - sleep(1000); - else - lckfd = open(lock, ORDWR); +Reopen: + while ((lckfd = open(lock, ORDWR)) < 0 && lockwait) + sleep(1000); if (lckfd < 0) sysfatal("can't open %s read/write: %r", lock); dir = dirfstat(lckfd); if (dir == nil) sysfatal("can't fstat %s: %r", lock); if (!(dir->mode & DMEXCL)) { + if(didwstat++) + sysfatal("exclusive bit does not stick for %s", lock); dir->mode |= DMEXCL; dir->qid.type |= QTEXCL; if (dirfwstat(lckfd, dir) < 0) sysfatal("can't make %s exclusive access: %r", lock); + /* reopen for lock to be effective */ + free(dir); + close(lckfd); + goto Reopen; } free(dir); return lckfd; |