From b374ab328be4535cff9412e265a3fb87c53c1272 Mon Sep 17 00:00:00 2001 From: Adam Dickmeiss Date: Fri, 30 Jun 2006 11:10:17 +0000 Subject: [PATCH] Experiments with file locks --- util/flock.c | 67 ++++++++++++++++++++++++++++++++++++++++++++----------- util/tstflock.c | 4 +++- 2 files changed, 57 insertions(+), 14 deletions(-) diff --git a/util/flock.c b/util/flock.c index 676b36a..5956832 100644 --- a/util/flock.c +++ b/util/flock.c @@ -1,4 +1,4 @@ -/* $Id: flock.c,v 1.9 2006-06-27 12:24:14 adam Exp $ +/* $Id: flock.c,v 1.10 2006-06-30 11:10:17 adam Exp $ Copyright (C) 1995-2006 Index Data ApS @@ -40,6 +40,10 @@ Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA #include #include +#define DEBUG_FLOCK 1 + +#define ALWAYS_FLOCK 1 + /** have this module (mutex) been initialized? */ static int initialized = 0; @@ -148,8 +152,6 @@ ZebraLockHandle zebra_lock_create(const char *dir, const char *name) { p->fname = fname; fname = 0; /* fname buffer now owned by p->fname */ - yaz_log(log_level, "zebra_lock_create fd=%d p=%p fname=%s", - p->fd, p, p->fname); #ifndef WIN32 zebra_lock_rdwr_init(&p->rdwr_lock); zebra_mutex_init(&p->file_mutex); @@ -168,6 +170,8 @@ ZebraLockHandle zebra_lock_create(const char *dir, const char *name) #ifndef WIN32 h->write_flag = 0; #endif + yaz_log(log_level, "zebra_lock_create fd=%d p=%p fname=%s", + h->p->fd, h, p->fname); } zebra_mutex_unlock(&lock_list_mutex); xfree(fname); /* free it - if it's still there */ @@ -182,13 +186,15 @@ void zebra_lock_destroy(ZebraLockHandle h) yaz_log(log_level, "zebra_lock_destroy fd=%d p=%p fname=%s", h->p->fd, h, h->p->fname); zebra_mutex_lock(&lock_list_mutex); - yaz_log(log_level, "zebra_lock_destroy fd=%d p=%p fname=%s 1", - h->p->fd, h, h->p->fname); + yaz_log(log_level, "zebra_lock_destroy fd=%d p=%p fname=%s refcount=%d", + h->p->fd, h, h->p->fname, h->p->ref_count); assert(h->p->ref_count > 0); --(h->p->ref_count); if (h->p->ref_count == 0) { struct zebra_lock_info **hp = &lock_list; + yaz_log(log_level, "zebra_lock_destroy fd=%d p=%p fname=%s remove", + h->p->fd, h, h->p->fname); while (*hp) { if (*hp == h->p) @@ -216,17 +222,27 @@ void zebra_lock_destroy(ZebraLockHandle h) static int unixLock(int fd, int type, int cmd) { struct flock area; + int r; area.l_type = type; area.l_whence = SEEK_SET; area.l_len = area.l_start = 0L; - return fcntl(fd, cmd, &area); + + yaz_log(log_level, "fcntl begin type=%d fd=%d", type, fd); + r = fcntl(fd, cmd, &area); + if (r == -1) + yaz_log(YLOG_WARN|YLOG_ERRNO, "fcntl FAIL type=%d fd=%d", type, fd); + else + yaz_log(log_level, "fcntl type=%d OK fd=%d", type, fd); + + return r; } #endif int zebra_lock_w(ZebraLockHandle h) { int r; - yaz_log(log_level, "zebra_lock_w fd=%d p=%p fname=%s", + int do_lock = ALWAYS_FLOCK; + yaz_log(log_level, "zebra_lock_w fd=%d p=%p fname=%s begin", h->p->fd, h, h->p->fname); #ifdef WIN32 @@ -235,22 +251,33 @@ int zebra_lock_w(ZebraLockHandle h) #else zebra_mutex_lock(&h->p->file_mutex); if (h->p->no_file_write_lock == 0) + do_lock = 1; + h->p->no_file_write_lock++; + zebra_mutex_unlock(&h->p->file_mutex); + if (do_lock) { + yaz_log(log_level, "zebra_lock_w fd=%d p=%p fname=%s 2", + h->p->fd, h, h->p->fname); /* if there is already a read lock.. upgrade to write lock */ r = unixLock(h->p->fd, F_WRLCK, F_SETLKW); } - h->p->no_file_write_lock++; - zebra_mutex_unlock(&h->p->file_mutex); + yaz_log(log_level, "zebra_lock_w fd=%d p=%p fname=%s 3", + h->p->fd, h, h->p->fname); zebra_lock_rdwr_wlock(&h->p->rdwr_lock); h->write_flag = 1; + yaz_log(log_level, "zebra_lock_w fd=%d p=%p fname=%s end", + h->p->fd, h, h->p->fname); #endif + return r; } int zebra_lock_r(ZebraLockHandle h) { int r; + int do_lock = ALWAYS_FLOCK; + yaz_log(log_level, "zebra_lock_r fd=%d p=%p fname=%s", h->p->fd, h, h->p->fname); #ifdef WIN32 @@ -259,12 +286,15 @@ int zebra_lock_r(ZebraLockHandle h) #else zebra_mutex_lock(&h->p->file_mutex); if (h->p->no_file_read_lock == 0 && h->p->no_file_write_lock == 0) + do_lock = 1; + h->p->no_file_read_lock++; + zebra_mutex_unlock(&h->p->file_mutex); + + if (do_lock) { /* only read lock if no write locks already */ r = unixLock(h->p->fd, F_RDLCK, F_SETLKW); } - h->p->no_file_read_lock++; - zebra_mutex_unlock(&h->p->file_mutex); zebra_lock_rdwr_rlock(&h->p->rdwr_lock); h->write_flag = 0; @@ -275,7 +305,8 @@ int zebra_lock_r(ZebraLockHandle h) int zebra_unlock(ZebraLockHandle h) { int r = 0; - yaz_log(log_level, "zebra_unlock fd=%d p=%p fname=%s", + int do_unlock = ALWAYS_FLOCK; + yaz_log(log_level, "zebra_unlock fd=%d p=%p fname=%s begin", h->p->fd, h, h->p->fname); #ifdef WIN32 r = _locking(h->p->fd, _LK_UNLCK, 1); @@ -292,9 +323,16 @@ int zebra_unlock(ZebraLockHandle h) h->p->no_file_read_lock--; if (h->p->no_file_read_lock == 0 && h->p->no_file_write_lock == 0) { - r = unixLock(h->p->fd, F_UNLCK, F_SETLKW); + do_unlock = 1; + yaz_log(log_level, "zebra_unlock fd=%d p=%p fname=%s 2", + h->p->fd, h, h->p->fname); } zebra_mutex_unlock(&h->p->file_mutex); + + if (do_unlock) + r = unixLock(h->p->fd, F_UNLCK, F_SETLKW); + yaz_log(log_level, "zebra_unlock fd=%d p=%p fname=%s end", + h->p->fd, h, h->p->fname); #endif return r; } @@ -304,6 +342,9 @@ void zebra_flock_init() if (!initialized) { log_level = yaz_log_module_level("flock"); +#if DEBUG_FLOCK + log_level = YLOG_LOG|YLOG_FLUSH; +#endif initialized = 1; zebra_mutex_init(&lock_list_mutex); } diff --git a/util/tstflock.c b/util/tstflock.c index 372f976..3725b8f 100644 --- a/util/tstflock.c +++ b/util/tstflock.c @@ -2,7 +2,7 @@ * Copyright (C) 1995-2006, Index Data ApS * See the file LICENSE for details. * - * $Id: tstflock.c,v 1.8 2006-06-27 12:24:14 adam Exp $ + * $Id: tstflock.c,v 1.9 2006-06-30 11:10:17 adam Exp $ */ #include @@ -125,6 +125,8 @@ int main(int argc, char **argv) { YAZ_CHECK_INIT(argc, argv); + yaz_log_time_format("%s:%!"); + zebra_flock_init(); #ifdef WIN32 tst_win32(2); -- 1.7.10.4