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

1 files changed, 57 insertions, 8 deletions

diff --git a/lib/libc/gen/getlogin.c b/lib/libc/gen/getlogin.c
index abf13131da3..b532c406246 100644
--- a/lib/libc/gen/getlogin.c
+++ b/lib/libc/gen/getlogin.c
@@ -32,7 +32,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: getlogin.c,v 1.3 1997/07/09 00:28:21 millert Exp $";
+static char rcsid[] = "$OpenBSD: getlogin.c,v 1.4 1998/11/20 11:18:39 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/param.h>
@@ -41,19 +41,68 @@ static char rcsid[] = "$OpenBSD: getlogin.c,v 1.3 1997/07/09 00:28:21 millert Ex
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
+#include <errno.h>
+#include "thread_private.h"
+
+_THREAD_PRIVATE_MUTEX(logname)
+static int  logname_valid = 0;
+static char logname[MAXLOGNAME + 1];
 
-int	__logname_valid;		/* known to setlogin() */
 int	_getlogin __P((char *, size_t));
+int	_setlogin __P((const char *));
 
 char *
 getlogin()
 {
-	static char logname[MAXLOGNAME + 1];
+	_THREAD_PRIVATE_KEY(getlogin)
+	char * name = (char *)_THREAD_PRIVATE(getlogin, logname, NULL);
 
-	if (__logname_valid == 0) {
-		if (_getlogin(logname, sizeof(logname) - 1) < 0)
-			return ((char *)NULL);
-		__logname_valid = 1;
+	if ((errno = getlogin_r(name, sizeof logname)) != 0)
+		return NULL;
+	if (*name == '\0') {
+		errno = ENOENT;  /* well? */
+		return NULL;
 	}
-	return (*logname ? logname : (char *)NULL);
+	return name;
+}
+
+int
+getlogin_r(name, namelen)
+	char *name;
+	size_t namelen;
+{
+	int logname_size;
+
+	if (name == NULL)
+		return EFAULT;
+
+	_THREAD_PRIVATE_MUTEX_LOCK(logname);
+	if (!logname_valid) {
+		if (_getlogin(logname, sizeof(logname) - 1) < 0) {
+			_THREAD_PRIVATE_MUTEX_UNLOCK(logname);
+			return errno;
+		}
+		logname_valid = 1;
+		logname[MAXLOGNAME] = '\0';	/* paranoia */
+	}
+	logname_size = strlen(logname) + 1;
+	if (namelen < logname_size)
+		return ERANGE;
+	memcpy(name, logname, logname_size);
+	_THREAD_PRIVATE_MUTEX_UNLOCK(logname);
+	return 0;
+}
+
+int
+setlogin(name)
+	const char *name;
+{
+	int ret;
+
+	_THREAD_PRIVATE_MUTEX_LOCK(logname);
+	ret = _setlogin(name);
+	if (ret == 0)
+		logname_valid = 0;
+	_THREAD_PRIVATE_MUTEX_UNLOCK(logname);
+	return ret;
 }