[libvirt] [PATCH 3/5] Implement a RWLock primitive for drivers to use
This implements a thin wrapper around the pthread_rwlock
primitives. No impl is provided for Win32 at this time
since it is rather hard, and none of our code yet requires
it on Win32
* src/util/threads.h: Add virRWLockInit, virRWLockDestroy,
virRWLockRead, virRWLockWrite, virRWLockUnlock APIs
* src/util/threads-pthread.h: define virRWLock struct
* src/util/threads-pthread.c: Implement RWLock APIs
---
src/libvirt_private.syms | 6 ++++++
src/util/threads-pthread.c | 30 ++++++++++++++++++++++++++++++
src/util/threads-pthread.h | 4 ++++
src/util/threads.h | 10 ++++++++++
4 files changed, 50 insertions(+), 0 deletions(-)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index f17d260..7b1e3c8 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -420,6 +420,12 @@ virCondWait;
virCondSignal;
virCondBroadcast;
+virRWLockInit;
+virRWLockDestroy;
+virRWLockRead;
+virRWLockWrite;
+virRWLockUnlock;
+
# util.h
virFileReadAll;
virFileWriteStr;
diff --git a/src/util/threads-pthread.c b/src/util/threads-pthread.c
index 4e00bc5..2052c0a 100644
--- a/src/util/threads-pthread.c
+++ b/src/util/threads-pthread.c
@@ -57,6 +57,36 @@ void virMutexUnlock(virMutexPtr m)
}
+int virRWLockInit(virRWLockPtr m)
+{
+ if (pthread_rwlock_init(&m->lock, NULL) != 0) {
+ errno = EINVAL;
+ return -1;
+ }
+ return 0;
+}
+
+void virRWLockDestroy(virRWLockPtr m)
+{
+ pthread_rwlock_destroy(&m->lock);
+}
+
+void virRWLockRead(virRWLockPtr m)
+{
+ pthread_rwlock_rdlock(&m->lock);
+}
+
+void virRWLockWrite(virRWLockPtr m)
+{
+ pthread_rwlock_wrlock(&m->lock);
+}
+
+void virRWLockUnlock(virRWLockPtr m)
+{
+ pthread_rwlock_unlock(&m->lock);
+}
+
+
int virCondInit(virCondPtr c)
{
diff --git a/src/util/threads-pthread.h b/src/util/threads-pthread.h
index 6404d1d..f2b546e 100644
--- a/src/util/threads-pthread.h
+++ b/src/util/threads-pthread.h
@@ -27,6 +27,10 @@ struct virMutex {
pthread_mutex_t lock;
};
+struct virRWLock {
+ pthread_rwlock_t lock;
+};
+
struct virCond {
pthread_cond_t cond;
};
diff --git a/src/util/threads.h b/src/util/threads.h
index 62239b7..be65031 100644
--- a/src/util/threads.h
+++ b/src/util/threads.h
@@ -27,6 +27,9 @@
typedef struct virMutex virMutex;
typedef virMutex *virMutexPtr;
+typedef struct virRWLock virRWLock;
+typedef virRWLock *virRWLockPtr;
+
typedef struct virCond virCond;
typedef virCond *virCondPtr;
@@ -44,6 +47,13 @@ void virMutexLock(virMutexPtr m);
void virMutexUnlock(virMutexPtr m);
+int virRWLockInit(virRWLockPtr m) ATTRIBUTE_RETURN_CHECK;
+void virRWLockDestroy(virRWLockPtr m);
+
+void virRWLockRead(virRWLockPtr m);
+void virRWLockWrite(virRWLockPtr m);
+void virRWLockUnlock(virRWLockPtr m);
+
int virCondInit(virCondPtr c) ATTRIBUTE_RETURN_CHECK;
int virCondDestroy(virCondPtr c) ATTRIBUTE_RETURN_CHECK;
--
1.6.2.5