[libvirt] [PATCH 02/14] Add virFileLock and virFileUnlock APIs
From: "Daniel P. Berrange" <berrange(a)redhat.com>
Add some simple wrappers around the fcntl() discretionary file
locking capability.
* src/util/util.c, src/util/util.h, src/libvirt_private.syms: Add
virFileLock and virFileUnlock APIs
---
src/libvirt_private.syms | 2 ++
src/util/util.c | 33 +++++++++++++++++++++++++++++++++
src/util/util.h | 3 +++
3 files changed, 38 insertions(+), 0 deletions(-)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index ae0d199..0746dee 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -993,6 +993,7 @@ virFileFindMountPoint;
virFileHasSuffix;
virFileIsExecutable;
virFileLinkPointsTo;
+virFileLock;
virFileMakePath;
virFileMatchesNameSuffix;
virFileOpenAs;
@@ -1004,6 +1005,7 @@ virFileReadPid;
virFileResolveLink;
virFileSanitizePath;
virFileStripSuffix;
+virFileUnlock;
virFileWaitForDevices;
virFileWriteStr;
virFindFileInPath;
diff --git a/src/util/util.c b/src/util/util.c
index 4710fc5..1d8083f 100644
--- a/src/util/util.c
+++ b/src/util/util.c
@@ -1175,6 +1175,39 @@ int virFileOpenTtyAt(const char *ptmx ATTRIBUTE_UNUSED,
}
#endif
+
+int virFileLock(int fd, bool shared, off_t start, off_t len)
+{
+ struct flock fl = {
+ .l_type = shared ? F_RDLCK : F_WRLCK,
+ .l_whence = SEEK_SET,
+ .l_start = start,
+ .l_len = len,
+ };
+
+ if (fcntl(fd, F_SETLK, &fl) < 0)
+ return -errno;
+
+ return 0;
+}
+
+
+int virFileUnlock(int fd, off_t start, off_t len)
+{
+ struct flock fl = {
+ .l_type = F_UNLCK,
+ .l_whence = SEEK_SET,
+ .l_start = start,
+ .l_len = len,
+ };
+
+ if (fcntl(fd, F_SETLK, &fl) < 0)
+ return -errno;
+
+ return 0;
+}
+
+
char* virFilePid(const char *dir, const char* name)
{
char *pidfile;
diff --git a/src/util/util.h b/src/util/util.h
index 1555653..820c9ff 100644
--- a/src/util/util.h
+++ b/src/util/util.h
@@ -117,6 +117,9 @@ int virFileOpenTtyAt(const char *ptmx,
char **ttyName,
int rawmode);
+int virFileLock(int fd, bool shared, off_t start, off_t len);
+int virFileUnlock(int fd, off_t start, off_t len);
+
char* virFilePid(const char *dir,
const char *name);
--
1.7.6