Add thread-safety to libc, so that libc_r will build (on i386 at least).

All POSIX libc api now there (to P1003.1c/D10)
  (more md stuff is needed for other libc/arch/*)
  (setlogin is no longer a special syscall)
Add -pthread option to gcc (that makes it use -lc_r and -D_POSIX_THREADS).
Doc some re-entrant routines
Add libc_r to intro(3)
dig() uses some libc srcs and an extra -I was needed there.
Add more md stuff to libc_r.
Update includes for the pthreads api
Update libc_r TODO

6 files changed, 70 insertions, 15 deletions

diff --git a/src/lib/libc/stdlib/Makefile.inc b/src/lib/libc/stdlib/Makefile.inc
index bdd5280dde..3191f08328 100644
--- a/src/lib/libc/stdlib/Makefile.inc
+++ b/src/lib/libc/stdlib/Makefile.inc
@@ -1,7 +1,7 @@
 #       $OpenBDS: Makefile.inc,v 1.6 1996/08/21 03:47:21 tholo Exp $
 
 # stdlib sources
-.PATH: ${.CURDIR}/arch/${MACHINE_ARCH}/stdlib ${.CURDIR}/stdlib
+.PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/stdlib ${LIBCSRCDIR}/stdlib
 
 SRCS+=  a64l.c abort.c atexit.c atoi.c atof.c atol.c bsearch.c calloc.c \
         cfree.c exit.c getenv.c getopt.c getsubopt.c heapsort.c l64a.c \
diff --git a/src/lib/libc/stdlib/abort.c b/src/lib/libc/stdlib/abort.c
index 4ea8a2ca4b..4cc6257acb 100644
--- a/src/lib/libc/stdlib/abort.c
+++ b/src/lib/libc/stdlib/abort.c
@@ -32,12 +32,13 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: abort.c,v 1.5 1997/06/22 20:21:25 tholo Exp $";
+static char *rcsid = "$OpenBSD: abort.c,v 1.6 1998/11/20 11:18:49 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <signal.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include "thread_private.h"
 
 void (*__cleanup)();
 
@@ -54,7 +55,11 @@ abort()
          * any errors -- X311J doesn't allow abort to return anyway.
          */
         sigdelset(&mask, SIGABRT);
+#ifdef _THREAD_SAFE
+        (void)_thread_sys_sigprocmask(SIG_SETMASK, &mask, (sigset_t *)NULL);
+#else  _THREAD_SAFE
         (void)sigprocmask(SIG_SETMASK, &mask, (sigset_t *)NULL);
+#endif _THREAD_SAFE
 
         /*
          * POSIX requires we flush stdio buffers on abort
@@ -71,7 +76,11 @@ abort()
          * it again, only harder.
          */
         (void)signal(SIGABRT, SIG_DFL);
+#ifdef _THREAD_SAFE
+        (void)_thread_sys_sigprocmask(SIG_SETMASK, &mask, (sigset_t *)NULL);
+#else  _THREAD_SAFE
         (void)sigprocmask(SIG_SETMASK, &mask, (sigset_t *)NULL);
+#endif _THREAD_SAFE
         (void)kill(getpid(), SIGABRT);
         exit(1);
 }
diff --git a/src/lib/libc/stdlib/exit.c b/src/lib/libc/stdlib/exit.c
index e358c94fd6..bc7fd395ca 100644
--- a/src/lib/libc/stdlib/exit.c
+++ b/src/lib/libc/stdlib/exit.c
@@ -32,7 +32,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: exit.c,v 1.2 1996/08/19 08:33:30 tholo Exp $";
+static char *rcsid = "$OpenBSD: exit.c,v 1.3 1998/11/20 11:18:50 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <stdlib.h>
@@ -42,6 +42,15 @@ static char *rcsid = "$OpenBSD: exit.c,v 1.2 1996/08/19 08:33:30 tholo Exp $";
 void (*__cleanup)();
 
 /*
+ * This variable is zero until a process has created a thread.
+ * It is used to avoid calling locking functions in libc when they
+ * are not required. By default, libc is intended to be(come)
+ * thread-safe, but without a (significant) penalty to non-threaded
+ * processes.
+ */
+int     __isthreaded    = 0;
+
+/*
  * Exit, flushing stdio buffers if necessary.
  */
 void
diff --git a/src/lib/libc/stdlib/malloc.c b/src/lib/libc/stdlib/malloc.c
index d1d8759791..ecbf93dc48 100644
--- a/src/lib/libc/stdlib/malloc.c
+++ b/src/lib/libc/stdlib/malloc.c
@@ -8,7 +8,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: malloc.c,v 1.32 1998/08/06 16:26:32 millert Exp $";
+static char rcsid[] = "$OpenBSD: malloc.c,v 1.33 1998/11/20 11:18:50 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 /*
@@ -87,15 +87,27 @@ static char rcsid[] = "$OpenBSD: malloc.c,v 1.32 1998/08/06 16:26:32 millert Exp
 #endif /* __OpenBSD__ */
 
 #ifdef _THREAD_SAFE
-#include <pthread.h>
-static pthread_mutex_t malloc_lock;
-#define THREAD_LOCK()           pthread_mutex_lock(&malloc_lock)
-#define THREAD_UNLOCK()         pthread_mutex_unlock(&malloc_lock)
-#define THREAD_LOCK_INIT()      pthread_mutex_init(&malloc_lock, 0);
+# include "thread_private.h"
+# if 0
+   /* kernel threads */
+#  include <pthread.h>
+   static pthread_mutex_t malloc_lock;
+#  define THREAD_LOCK()         pthread_mutex_lock(&malloc_lock)
+#  define THREAD_UNLOCK()       pthread_mutex_unlock(&malloc_lock)
+#  define THREAD_LOCK_INIT()    pthread_mutex_init(&malloc_lock, 0);
+# else
+   /* user threads */
+#  include "spinlock.h"
+   static spinlock_t malloc_lock = _SPINLOCK_INITIALIZER;
+#  define THREAD_LOCK()         if (__isthreaded) _SPINLOCK(&malloc_lock)
+#  define THREAD_UNLOCK()       if (__isthreaded) _SPINUNLOCK(&malloc_lock)
+#  define THREAD_LOCK_INIT()    
+# endif
 #else
-#define THREAD_LOCK()
-#define THREAD_UNLOCK()
-#define THREAD_LOCK_INIT()
+  /* no threads */
+# define THREAD_LOCK()
+# define THREAD_UNLOCK()
+# define THREAD_LOCK_INIT()
 #endif
 
 /*
diff --git a/src/lib/libc/stdlib/rand.3 b/src/lib/libc/stdlib/rand.3
index 32d32761f1..28496ec12a 100644
--- a/src/lib/libc/stdlib/rand.3
+++ b/src/lib/libc/stdlib/rand.3
@@ -33,7 +33,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     $OpenBSD: rand.3,v 1.4 1998/07/05 19:54:22 millert Exp $
+.\"     $OpenBSD: rand.3,v 1.5 1998/11/20 11:18:50 d Exp $
 .\"
 .Dd June 29, 1991
 .Dt RAND 3
@@ -48,6 +48,8 @@
 .Fn srand "unsigned seed"
 .Ft int
 .Fn rand void
+.Ft int
+.Fn rand_r "unsigned int *seed"
 .Sh DESCRIPTION
 .Bf -symbolic
 These interfaces are obsoleted by
@@ -73,6 +75,14 @@ with the same seed value.
 .Pp
 If no seed value is provided, the functions are automatically
 seeded with a value of 1.
+.Pp
+The
+.Fn rand_r
+is a thread-safe version of
+.Fn rand .
+Storage for the seed must be provided through the
+.Ar seed
+argument, and needs to have been initialized by the caller.
 .Sh SEE ALSO
 .Xr arc4random 3 ,
 .Xr rand48 3 ,
@@ -85,3 +95,10 @@ and
 functions
 conform to
 .St -ansiC .
+.Pp
+The
+.Fn rand_r
+function
+conforms to ISO/IEC 9945-1 ANSI/IEEE
+.Pq Dq Tn POSIX
+Std 1003.1c Draft 10.
diff --git a/src/lib/libc/stdlib/rand.c b/src/lib/libc/stdlib/rand.c
index f270ffd986..61fb66e5ec 100644
--- a/src/lib/libc/stdlib/rand.c
+++ b/src/lib/libc/stdlib/rand.c
@@ -32,7 +32,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: rand.c,v 1.2 1996/08/19 08:33:44 tholo Exp $";
+static char *rcsid = "$OpenBSD: rand.c,v 1.3 1998/11/20 11:18:50 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/types.h>
@@ -41,9 +41,17 @@ static char *rcsid = "$OpenBSD: rand.c,v 1.2 1996/08/19 08:33:44 tholo Exp $";
 static u_long next = 1;
 
 int
+rand_r(seed)
+u_int *seed;
+{
+        *seed = *seed * 1103515245 + 12345;
+        return (u_int)(*seed / 65536) % ((u_int)RAND_MAX + 1);
+}
+
+int
 rand()
 {
-        return ((next = next * 1103515245 + 12345) % ((u_int)RAND_MAX + 1));
+        return rand_r(&next);
 }
 
 void