[libvirt] [PATCH] Include a thread identifier in log messages

[Daniel P. Berrange]

To allow messages from different threads to be untangled,
include an integer thread identifier in log messages.

* src/util/logging.c: Include thread ID
* src/util/threads.h, src/util/threads.h, src/util/threads-pthread.c:
  Add new virThreadSelfID() function
* configure.ac: Check for sys/syscall.h
---
 configure.ac               |    2 +-
 src/libvirt_private.syms   |    1 +
 src/util/logging.c         |    6 ++++--
 src/util/threads-pthread.c |   16 ++++++++++++++++
 src/util/threads-win32.c   |   16 ++++++++++++++++
 src/util/threads.h         |    1 +
 6 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/configure.ac b/configure.ac
index b912a7a..af1dfec 100644
--- a/configure.ac
+++ b/configure.ac
@@ -110,7 +110,7 @@ LIBS=$old_libs
 dnl Availability of various common headers (non-fatal if missing).
 AC_CHECK_HEADERS([pwd.h paths.h regex.h sys/syslimits.h sys/un.h \
   sys/poll.h syslog.h mntent.h net/ethernet.h linux/magic.h \
-  sys/un.h])
+  sys/un.h sys/syscall.h])
 
 AC_CHECK_LIB([intl],[gettext],[])
 
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index e808375..3bb1762 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -781,6 +781,7 @@ virThreadCreate;
 virThreadIsSelf;
 virThreadJoin;
 virThreadSelf;
+virThreadSelfID;
 
 
 # usb.h
diff --git a/src/util/logging.c b/src/util/logging.c
index ac38d4d..d65dec0 100644
--- a/src/util/logging.c
+++ b/src/util/logging.c
@@ -548,14 +548,16 @@ void virLogMessage(const char *category, int priority, const char *funcname,
     localtime_r(&cur_time.tv_sec, &time_info);
 
     if ((funcname != NULL)) {
-        ret = virAsprintf(&msg, "%02d:%02d:%02d.%03d: %s : %s:%lld : %s\n",
+        ret = virAsprintf(&msg, "%02d:%02d:%02d.%03d: %d: %s : %s:%lld : %s\n",
                           time_info.tm_hour, time_info.tm_min,
                           time_info.tm_sec, (int) cur_time.tv_usec / 1000,
+                          virThreadSelfID(),
                           virLogPriorityString(priority), funcname, linenr, str);
     } else {
-        ret = virAsprintf(&msg, "%02d:%02d:%02d.%03d: %s : %s\n",
+        ret = virAsprintf(&msg, "%02d:%02d:%02d.%03d: %d: %s : %s\n",
                           time_info.tm_hour, time_info.tm_min,
                           time_info.tm_sec, (int) cur_time.tv_usec / 1000,
+                          virThreadSelfID(),
                           virLogPriorityString(priority), str);
     }
     VIR_FREE(str);
diff --git a/src/util/threads-pthread.c b/src/util/threads-pthread.c
index 34d9ce8..02070ae 100644
--- a/src/util/threads-pthread.c
+++ b/src/util/threads-pthread.c
@@ -21,6 +21,11 @@
 
 #include <config.h>
 
+#include <unistd.h>
+#if HAVE_SYS_SYSCALL_H
+# include <sys/syscall.h>
+#endif
+
 
 /* Nothing special required for pthreads */
 int virThreadInitialize(void)
@@ -170,6 +175,17 @@ bool virThreadIsSelf(virThreadPtr thread)
     return pthread_equal(pthread_self(), thread->thread) ? true : false;
 }
 
+int virThreadSelfID(void)
+{
+#if defined(HAVE_SYS_SYSCALL_H) && defined(SYS_gettid)
+    pid_t tid;
+    tid = syscall(SYS_gettid);
+    return (int)tid;
+#else
+    return (int)pthread_self();
+#endif
+}
+
 void virThreadJoin(virThreadPtr thread)
 {
     pthread_join(thread->thread, NULL);
diff --git a/src/util/threads-win32.c b/src/util/threads-win32.c
index de73fd5..45c7eef 100644
--- a/src/util/threads-win32.c
+++ b/src/util/threads-win32.c
@@ -288,6 +288,22 @@ bool virThreadIsSelf(virThreadPtr thread)
     return self.thread == thread->thread ? true : false;
 }
 
+int virThreadSelfID(void)
+{
+    HANDLE handle = GetCurrentThread();
+    HANDLE process = GetCurrentProcess();
+    HANDLE thread;
+    int id;
+
+    DuplicateHandle(process, handle, process,
+                    &thread, 0, FALSE,
+                    DUPLICATE_SAME_ACCESS);
+    id = (int)thread;
+    CloseHandle(thread);
+    return id;
+}
+
+
 void virThreadJoin(virThreadPtr thread)
 {
     if (thread->joinable) {
diff --git a/src/util/threads.h b/src/util/threads.h
index b3b827d..fa00a91 100644
--- a/src/util/threads.h
+++ b/src/util/threads.h
@@ -51,6 +51,7 @@ int virThreadCreate(virThreadPtr thread,
 void virThreadSelf(virThreadPtr thread);
 bool virThreadIsSelf(virThreadPtr thread);
 void virThreadJoin(virThreadPtr thread);
+int virThreadSelfID(void);
 
 int virMutexInit(virMutexPtr m) ATTRIBUTE_RETURN_CHECK;
 int virMutexInitRecursive(virMutexPtr m) ATTRIBUTE_RETURN_CHECK;
-- 
1.7.2.3