[libvirt] [PATCH 07/11] Introduce portability APIs for creating threads

[Daniel P. Berrange]

The util/threads.c/h code already has APIs for mutexes,
condition variables and thread locals. This commit adds
in code for actually creating threads.

* src/libvirt_private.syms: Export new symbols
* src/util/threads.h: Define APIs virThreadCreate, virThreadSelf,
  virThreadIsSelf and virThreadJoin
* src/util/threads-win32.c, src/util/threads-win32.h: Win32
  impl of threads
* src/util/threads-pthread.c, src/util/threads-pthread.h: POSIX
  impl of threads
---
 src/libvirt_private.syms   |    4 +++
 src/util/threads-pthread.c |   45 ++++++++++++++++++++++++++++++++++++++++++
 src/util/threads-pthread.h |    4 +++
 src/util/threads-win32.c   |   47 ++++++++++++++++++++++++++++++++++++++++++++
 src/util/threads-win32.h   |    3 ++
 src/util/threads.h         |   15 ++++++++++++++
 6 files changed, 118 insertions(+), 0 deletions(-)

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 693e2ed..d8287ce 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -713,6 +713,10 @@ virMutexInit;
 virMutexInitRecursive;
 virMutexLock;
 virMutexUnlock;
+virThreadCreate;
+virThreadIsSelf;
+virThreadJoin;
+virThreadSelf;
 
 
 # usb.h
diff --git a/src/util/threads-pthread.c b/src/util/threads-pthread.c
index 030b33f..0bc413c 100644
--- a/src/util/threads-pthread.c
+++ b/src/util/threads-pthread.c
@@ -129,6 +129,51 @@ void virCondBroadcast(virCondPtr c)
     pthread_cond_broadcast(&c->cond);
 }
 
+struct virThreadArgs {
+    virThreadFunc func;
+    void *opaque;
+};
+
+static void *virThreadHelper(void *data)
+{
+    struct virThreadArgs *args = data;
+    args->func(args->opaque);
+    return NULL;
+}
+
+int virThreadCreate(virThreadPtr thread,
+                    bool joinable,
+                    virThreadFunc func,
+                    void *opaque)
+{
+    struct virThreadArgs args = { func, opaque };
+    pthread_attr_t attr;
+    pthread_attr_init(&attr);
+    if (!joinable)
+        pthread_attr_setdetachstate(&attr, 1);
+
+    int ret = pthread_create(&thread->thread, &attr, virThreadHelper, &args);
+    if (ret != 0) {
+        errno = ret;
+        return -1;
+    }
+    return 0;
+}
+
+void virThreadSelf(virThreadPtr thread)
+{
+    thread->thread = pthread_self();
+}
+
+bool virThreadIsSelf(virThreadPtr thread)
+{
+    return pthread_self() == thread->thread ? true : false;
+}
+
+void virThreadJoin(virThreadPtr thread)
+{
+    pthread_join(thread->thread, NULL);
+}
 
 int virThreadLocalInit(virThreadLocalPtr l,
                        virThreadLocalCleanup c)
diff --git a/src/util/threads-pthread.h b/src/util/threads-pthread.h
index 6404d1d..b25d0c2 100644
--- a/src/util/threads-pthread.h
+++ b/src/util/threads-pthread.h
@@ -31,6 +31,10 @@ struct virCond {
     pthread_cond_t cond;
 };
 
+struct virThread {
+    pthread_t thread;
+};
+
 struct virThreadLocal {
     pthread_key_t key;
 };
diff --git a/src/util/threads-win32.c b/src/util/threads-win32.c
index fe1fcd0..3f69f41 100644
--- a/src/util/threads-win32.c
+++ b/src/util/threads-win32.c
@@ -21,6 +21,8 @@
 
 #include <config.h>
 
+#include <process.h>
+
 #include "memory.h"
 
 struct virThreadLocalData {
@@ -205,6 +207,51 @@ void virCondBroadcast(virCondPtr c)
 }
 
 
+struct virThreadArgs {
+    virThreadFunc func;
+    void *opaque;
+};
+
+static unsigned int __stdcall virThreadHelper(void *data)
+{
+    struct virThreadArgs *args = data;
+    args->func(args->opaque);
+    return 0;
+}
+
+int virThreadCreate(virThreadPtr thread,
+                    bool joinable ATTRIBUTE_UNUSED,
+                    virThreadFunc func,
+                    void *opaque)
+{
+    struct virThreadArgs args = { func, opaque };
+    thread->thread = (HANDLE)_beginthreadex(NULL, 0, virThreadHelper, &args, 0, NULL);
+    return 0;
+}
+
+void virThreadSelf(virThreadPtr thread)
+{
+    HANDLE handle = GetCurrentThread();
+    HANDLE process = GetCurrentProcess();
+
+    DuplicateHandle(process, handle, process,
+                    &thread->thread, 0, FALSE,
+                    DUPLICATE_SAME_ACCESS);
+}
+
+bool virThreadIsSelf(virThreadPtr thread)
+{
+    virThread self;
+    virThreadSelf(&self);
+    return self.thread == thread->thread ? true : false;
+}
+
+void virThreadJoin(virThreadPtr thread)
+{
+    WaitForSingleObject(thread->thread, INFINITE);
+    CloseHandle(thread->thread);
+}
+
 
 int virThreadLocalInit(virThreadLocalPtr l,
                        virThreadLocalCleanup c)
diff --git a/src/util/threads-win32.h b/src/util/threads-win32.h
index 783d91d..7142884 100644
--- a/src/util/threads-win32.h
+++ b/src/util/threads-win32.h
@@ -33,6 +33,9 @@ struct virCond {
     HANDLE *waiters;
 };
 
+struct virThread {
+    HANDLE thread;
+};
 
 struct virThreadLocal {
     DWORD key;
diff --git a/src/util/threads.h b/src/util/threads.h
index db54ea0..b3b827d 100644
--- a/src/util/threads.h
+++ b/src/util/threads.h
@@ -22,6 +22,8 @@
 #ifndef __THREADS_H_
 # define __THREADS_H_
 
+# include <stdbool.h>
+
 # include "internal.h"
 
 typedef struct virMutex virMutex;
@@ -33,10 +35,23 @@ typedef virCond *virCondPtr;
 typedef struct virThreadLocal virThreadLocal;
 typedef virThreadLocal *virThreadLocalPtr;
 
+typedef struct virThread virThread;
+typedef virThread *virThreadPtr;
+
 
 int virThreadInitialize(void) ATTRIBUTE_RETURN_CHECK;
 void virThreadOnExit(void);
 
+typedef void (*virThreadFunc)(void *opaque);
+
+int virThreadCreate(virThreadPtr thread,
+                    bool joinable,
+                    virThreadFunc func,
+                    void *opaque) ATTRIBUTE_RETURN_CHECK;
+void virThreadSelf(virThreadPtr thread);
+bool virThreadIsSelf(virThreadPtr thread);
+void virThreadJoin(virThreadPtr thread);
+
 int virMutexInit(virMutexPtr m) ATTRIBUTE_RETURN_CHECK;
 int virMutexInitRecursive(virMutexPtr m) ATTRIBUTE_RETURN_CHECK;
 void virMutexDestroy(virMutexPtr m);
-- 
1.7.2.3