Detect availability of pthread_rwlock_timedwrlock() before using it.

(closes issue #14930)
 Reported by: tilghman
 Patches: 
       20090420__bug14930.diff.txt uploaded by tilghman (license 14)
 Tested by: mvanbaak, tilghman


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@190092 65c4cc65-6c06-0410-ace0-fbb531ad65f3

configure

@@ -1,5 +1,5 @@
 #! /bin/sh
-# From configure.ac Revision: 183241 .
+# From configure.ac Revision: 189601 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.61 for asterisk 1.4.
 #
@@ -12283,11 +12283,13 @@ _ACEOF
 cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
-#include <stdio.h>
+#include <sys/types.h> /* for off_t */
+     #include <stdio.h>
 int
 main ()
 {
-return fseeko (stdin, 0, 0) && (fseeko) (stdin, 0, 0);
+int (*fp) (FILE *, off_t, int) = fseeko;
+     return fseeko (stdin, 0, 0) && fp (stdin, 0, 0);
   ;
   return 0;
 }
@@ -12327,11 +12329,13 @@ cat confdefs.h >>conftest.$ac_ext
 cat >>conftest.$ac_ext <<_ACEOF
 /* end confdefs.h.  */
 #define _LARGEFILE_SOURCE 1
-#include <stdio.h>
+#include <sys/types.h> /* for off_t */
+     #include <stdio.h>
 int
 main ()
 {
-return fseeko (stdin, 0, 0) && (fseeko) (stdin, 0, 0);
+int (*fp) (FILE *, off_t, int) = fseeko;
+     return fseeko (stdin, 0, 0) && fp (stdin, 0, 0);
   ;
   return 0;
 }
@@ -15080,6 +15084,73 @@ fi
 rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
       conftest$ac_exeext conftest.$ac_ext
 
+{ echo "$as_me:$LINENO: checking for pthread_rwlock_timedwrlock() in pthread.h" >&5
+echo $ECHO_N "checking for pthread_rwlock_timedwrlock() in pthread.h... $ECHO_C" >&6; }
+saved_LDFLAGS="${LDFLAGS}"
+LDFLAGS="${LDFLAGS} -lpthread"
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+#include <pthread.h>
+     #include <time.h>
+int
+main ()
+{
+pthread_rwlock_t foo; struct timespec bar; pthread_rwlock_timedwrlock(&foo, &bar)
+  ;
+  return 0;
+}
+
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_link") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_c_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest$ac_exeext &&
+       $as_test_x conftest$ac_exeext; then
+
+    { echo "$as_me:$LINENO: result: yes" >&5
+echo "${ECHO_T}yes" >&6; }
+    ac_cv_pthread_rwlock_timedwrlock="yes"
+
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+    { echo "$as_me:$LINENO: result: no" >&5
+echo "${ECHO_T}no" >&6; }
+    ac_cv_pthread_rwlock_timedwrlock="no"
+
+
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
+      conftest$ac_exeext conftest.$ac_ext
+LDFLAGS="${saved_LDFLAGS}"
+if test "${ac_cv_pthread_rwlock_timedwrlock}" = "yes"; then
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_PTHREAD_RWLOCK_TIMEDWRLOCK 1
+_ACEOF
+
+fi
+
 { echo "$as_me:$LINENO: checking for compiler atomic operations" >&5
 echo $ECHO_N "checking for compiler atomic operations... $ECHO_C" >&6; }
 cat >conftest.$ac_ext <<_ACEOF

configure.ac

@@ -325,6 +325,27 @@ AC_LINK_IFELSE(
         AC_MSG_RESULT(no)
 )
 
+AC_MSG_CHECKING(for pthread_rwlock_timedwrlock() in pthread.h)
+saved_LDFLAGS="${LDFLAGS}"
+LDFLAGS="${LDFLAGS} -lpthread"
+AC_LINK_IFELSE(
+  [AC_LANG_PROGRAM(
+    [#include <pthread.h>
+     #include <time.h>],
+    [pthread_rwlock_t foo; struct timespec bar; pthread_rwlock_timedwrlock(&foo, &bar)])
+  ],[
+    AC_MSG_RESULT(yes)
+    ac_cv_pthread_rwlock_timedwrlock="yes"
+  ],[
+    AC_MSG_RESULT(no)
+    ac_cv_pthread_rwlock_timedwrlock="no"
+  ]
+)
+LDFLAGS="${saved_LDFLAGS}"
+if test "${ac_cv_pthread_rwlock_timedwrlock}" = "yes"; then
+  AC_DEFINE([HAVE_PTHREAD_RWLOCK_TIMEDWRLOCK], 1, [Define if your system has pthread_rwlock_timedwrlock()])
+fi
+
 AC_MSG_CHECKING(for compiler atomic operations)
 AC_LINK_IFELSE(
 AC_LANG_PROGRAM([], [int foo1; int foo2 = __sync_fetch_and_add(&foo1, 1);]),

include/asterisk/autoconfig.h.in

@@ -313,6 +313,9 @@
 /* Define to 1 if your system has PTHREAD_RWLOCK_PREFER_WRITER_NP. */
 #undef HAVE_PTHREAD_RWLOCK_PREFER_WRITER_NP
 
+/* Define if your system has pthread_rwlock_timedwrlock() */
+#undef HAVE_PTHREAD_RWLOCK_TIMEDWRLOCK
+
 /* Define to 1 if the system has the type `ptrdiff_t'. */
 #undef HAVE_PTRDIFF_T
 

include/asterisk/lock.h

@@ -50,6 +50,9 @@
 #include <time.h>
 #include <sys/param.h>
 
+#ifndef HAVE_PTHREAD_RWLOCK_TIMEDWRLOCK
+#include "asterisk/time.h"
+#endif
 #include "asterisk/logger.h"
 
 /* internal macro to profile mutexes. Only computes the delay on
@@ -1018,7 +1021,23 @@ static inline int _ast_rwlock_timedrdlock(ast_rwlock_t *lock, const char *name,
 #endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
 	
 	ast_store_lock_info(AST_RDLOCK, file, line, func, name, lock);
+#ifdef HAVE_PTHREAD_RWLOCK_TIMEDWRLOCK
 	res = pthread_rwlock_timedrdlock(lock, abs_timeout);
+#else
+	do {
+		struct timeval _start = ast_tvnow(), _diff;
+		for (;;) {
+			if (!(res = pthread_rwlock_tryrdlock(&t->lock))) {
+				break;
+			}
+			_diff = ast_tvsub(ast_tvnow(), _start);
+			if (_diff.tv_sec > abs_timeout->tv_sec || (_diff.tv_sec == abs_timeout->tv_sec && _diff.tv_usec * 1000 > abs_timeout->tv_nsec)) {
+				break;
+			}
+			usleep(1);
+		}
+	} while (0);
+#endif
 	if (!res)
 		ast_mark_lock_acquired(lock);
 	else
@@ -1051,7 +1070,23 @@ static inline int _ast_rwlock_timedwrlock(ast_rwlock_t *lock, const char *name,
 #endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
 
 	ast_store_lock_info(AST_WRLOCK, file, line, func, name, lock);
+#ifdef HAVE_PTHREAD_RWLOCK_TIMEDWRLOCK
 	res = pthread_rwlock_timedwrlock(lock, abs_timeout);
+#else
+	do {
+		struct timeval _start = ast_tvnow(), _diff;
+		for (;;) {
+			if (!(res = pthread_rwlock_trywrlock(&t->lock))) {
+				break;
+			}
+			_diff = ast_tvsub(ast_tvnow(), _start);
+			if (_diff.tv_sec > abs_timeout->tv_sec || (_diff.tv_sec == abs_timeout->tv_sec && _diff.tv_usec * 1000 > abs_timeout->tv_nsec)) {
+				break;
+			}
+			usleep(1);
+		}
+	} while (0);
+#endif
 	if (!res)
 		ast_mark_lock_acquired(lock);
 	else
@@ -1160,7 +1195,23 @@ static inline int ast_rwlock_rdlock(ast_rwlock_t *prwlock)
 
 static inline int ast_rwlock_timedrdlock(ast_rwlock_t *prwlock, const struct timespec *abs_timeout)
 {
-	return pthread_rwlock_timedrdlock(prwlock, abs_timeout);
+	int res;
+#ifdef HAVE_PTHREAD_RWLOCK_TIMEDWRLOCK
+	res = pthread_rwlock_timedrdlock(prwlock, abs_timeout);
+#else
+	struct timeval _start = ast_tvnow(), _diff;
+	for (;;) {
+		if (!(res = pthread_rwlock_tryrdlock(prwlock))) {
+			break;
+		}
+		_diff = ast_tvsub(ast_tvnow(), _start);
+		if (_diff.tv_sec > abs_timeout->tv_sec || (_diff.tv_sec == abs_timeout->tv_sec && _diff.tv_usec * 1000 > abs_timeout->tv_nsec)) {
+			break;
+		}
+		usleep(1);
+	}
+#endif
+	return res;
 }
 
 static inline int ast_rwlock_tryrdlock(ast_rwlock_t *prwlock)
@@ -1175,7 +1226,25 @@ static inline int ast_rwlock_wrlock(ast_rwlock_t *prwlock)
 
 static inline int ast_rwlock_timedwrlock(ast_rwlock_t *prwlock, const struct timespec *abs_timeout)
 {
-	return pthread_rwlock_timedwrlock(prwlock, abs_timeout);
+	int res;
+#ifdef HAVE_PTHREAD_RWLOCK_TIMEDWRLOCK
+	res = pthread_rwlock_timedwrlock(prwlock, abs_timeout);
+#else
+	do {
+		struct timeval _start = ast_tvnow(), _diff;
+		for (;;) {
+			if (!(res = pthread_rwlock_trywrlock(prwlock))) {
+				break;
+			}
+			_diff = ast_tvsub(ast_tvnow(), _start);
+			if (_diff.tv_sec > abs_timeout->tv_sec || (_diff.tv_sec == abs_timeout->tv_sec && _diff.tv_usec * 1000 > abs_timeout->tv_nsec)) {
+				break;
+			}
+			usleep(1);
+		}
+	} while (0);
+#endif
+	return res;
 }
 
 static inline int ast_rwlock_trywrlock(ast_rwlock_t *prwlock)