Fix for configure to detect library correctly.

Fix to check library in use during runtime.
Fix for Bug#16995, "idle connections not being killed due to timeout when NPTL is used".


BUILD/SETUP.sh:
  To avoid warnings during compilation.
configure.in:
  Fixed configure so that it can correctly detect
  between NPTL and Linuxthreads.
include/my_global.h:
  Fix for Linuxthreads.
include/my_pthread.h:
  Added defines for different libraries that can be detected.
  Currently only 'other', 'nptl', and 'lt' (linuxthreads) are
  being used.
  
  changed sigset() and signal() to my_sigset() and my_signal()
include/thr_alarm.h:
  Removed defines for Linuxthreads. This is now detected during
  runtime and handled in the thr_alarm.c
mysys/my_pthread.c:
  Runtime check for library.
mysys/thr_alarm.c:
  Runtime checks for library and corresponding
  signals.
sql/mysqld.cc:
  Added function for detecting thread library in use
  during start-up.
  
  THR_KILL_SIGNAL removed, setting signals during runtime.

3 files changed, 36 insertions, 17 deletions

diff --git a/include/my_global.h b/include/my_global.h
index 37e53c65dec..e6bf9a9b840 100644
--- a/include/my_global.h
+++ b/include/my_global.h
@@ -97,7 +97,7 @@
 
 
 /* Fix problem with S_ISLNK() on Linux */
-#if defined(HAVE_LINUXTHREADS)
+#if defined(TARGET_OS_LINUX) || defined(__GLIBC__)
 #undef  _GNU_SOURCE
 #define _GNU_SOURCE 1
 #endif
@@ -348,7 +348,10 @@ int	__void__;
 #endif
 
 /* Define some useful general macros */
-#if !defined(max)
+#if defined(__cplusplus) && defined(__GNUC__)
+#define max(a, b)     ((a) >? (b))
+#define min(a, b)     ((a) <? (b))
+#elif !defined(max)
 #define max(a, b)	((a) > (b) ? (a) : (b))
 #define min(a, b)	((a) < (b) ? (a) : (b))
 #endif
diff --git a/include/my_pthread.h b/include/my_pthread.h
index 7620b46e08b..e1a7ecab4ab 100644
--- a/include/my_pthread.h
+++ b/include/my_pthread.h
@@ -28,6 +28,14 @@
 extern "C" {
 #endif /* __cplusplus */ 
 
+/* Thread library */
+
+#define THD_LIB_OTHER 1
+#define THD_LIB_NPTL  2
+#define THD_LIB_LT    4
+
+extern uint thd_lib_detected;
+
 #if defined(__WIN__) || defined(OS2)
 
 #ifdef OS2
@@ -286,8 +294,8 @@ extern int my_pthread_create_detached;
 #undef HAVE_PTHREAD_RWLOCK_RDLOCK
 #undef HAVE_SNPRINTF
 
-#define sigset(A,B) pthread_signal((A),(void (*)(int)) (B))
-#define signal(A,B) pthread_signal((A),(void (*)(int)) (B))
+#define my_sigset(A,B) pthread_signal((A),(void (*)(int)) (B))
+#define my_signal(A,B) pthread_signal((A),(void (*)(int)) (B))
 #define my_pthread_attr_setprio(A,B)
 #endif /* defined(PTHREAD_SCOPE_GLOBAL) && !defined(PTHREAD_SCOPE_SYSTEM) */
 
@@ -324,14 +332,27 @@ extern int my_pthread_cond_init(pthread_cond_t *mp,
 #if !defined(HAVE_SIGWAIT) && !defined(HAVE_mit_thread) && !defined(HAVE_rts_threads) && !defined(sigwait) && !defined(alpha_linux_port) && !defined(HAVE_NONPOSIX_SIGWAIT) && !defined(HAVE_DEC_3_2_THREADS) && !defined(_AIX)
 int sigwait(sigset_t *setp, int *sigp);		/* Use our implemention */
 #endif
-#if !defined(HAVE_SIGSET) && !defined(HAVE_mit_thread) && !defined(sigset)
-#define sigset(A,B) do { struct sigaction s; sigset_t set;              \
-                         sigemptyset(&set);                             \
-                         s.sa_handler = (B);                            \
-                         s.sa_mask    = set;                            \
-                         s.sa_flags   = 0;                              \
-                         sigaction((A), &s, (struct sigaction *) NULL); \
+
+/*
+  We define my_sigset() and use that instead of the system sigset() so that
+  we can favor an implementation based on sigaction(). On some systems, such
+  as Mac OS X, sigset() results in flags such as SA_RESTART being set, and
+  we want to make sure that no such flags are set.
+*/
+#if defined(HAVE_SIGACTION) && !defined(my_sigset)
+#define my_sigset(A,B) do { struct sigaction s; sigset_t set; int rc;      \
+                            DBUG_ASSERT((A) != 0);                         \
+                            sigemptyset(&set);                             \
+                            s.sa_handler = (B);                            \
+                            s.sa_mask    = set;                            \
+                            s.sa_flags   = 0;                              \
+                            rc= sigaction((A), &s, (struct sigaction *) NULL); \
+                            DBUG_ASSERT(rc == 0);                          \
                        } while (0)
+#elif defined(HAVE_SIGSET) && !defined(my_sigset)
+#define my_sigset(A,B) sigset((A),(B))
+#elif !defined(my_sigset)
+#define my_sigset(A,B) signal((A),(B))
 #endif
 
 #ifndef my_pthread_setprio
@@ -416,7 +437,7 @@ struct tm *localtime_r(const time_t *clock, struct tm *res);
 #undef	pthread_detach_this_thread
 #define pthread_detach_this_thread() { pthread_t tmp=pthread_self() ; pthread_detach(tmp); }
 #undef sigset
-#define sigset(A,B) pthread_signal((A),(void (*)(int)) (B))
+#define my_sigset(A,B) pthread_signal((A),(void (*)(int)) (B))
 #endif
 
 #if ((defined(HAVE_PTHREAD_ATTR_CREATE) && !defined(HAVE_SIGWAIT)) || defined(HAVE_DEC_3_2_THREADS)) && !defined(HAVE_CTHREADS_WRAPPER)
diff --git a/include/thr_alarm.h b/include/thr_alarm.h
index 7a10d6886ce..0c26a67acf4 100644
--- a/include/thr_alarm.h
+++ b/include/thr_alarm.h
@@ -25,11 +25,6 @@ extern "C" {
 #ifndef USE_ALARM_THREAD
 #define USE_ONE_SIGNAL_HAND		/* One must call process_alarm */
 #endif
-#ifdef HAVE_LINUXTHREADS
-#define THR_CLIENT_ALARM SIGALRM
-#else
-#define THR_CLIENT_ALARM SIGUSR1
-#endif
 #ifdef HAVE_rts_threads
 #undef USE_ONE_SIGNAL_HAND
 #define USE_ALARM_THREAD