Allow threading libraries to register their own locking

implementation in case default one provided by rtld is
not suitable.

Consolidate various identical MD lock implementation into
a single file using appropriate machine/atomic.h.

Approved by:	re (scottl)

1 files changed, 63 insertions, 0 deletions

diff --git a/libexec/rtld-elf/rtld_lock.h b/libexec/rtld-elf/rtld_lock.h
new file mode 100644
index 0000000..941b19e
--- /dev/null
+++ b/libexec/rtld-elf/rtld_lock.h
@@ -0,0 +1,63 @@
+/*-
+ * Copyright 2003 Alexander Kabaev.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _RTLD_LOCK_H_
+#define	_RTLD_LOCK_H_
+
+#define	RTLI_VERSION	0x01
+
+struct RtldLockInfo
+{
+	unsigned int rtli_version;
+	void *(*lock_create)();
+	void  (*lock_destroy)(void *);
+	void  (*rlock_acquire)(void *);
+	void  (*wlock_acquire)(void *);
+	void  (*lock_release)(void *);
+	int   (*thread_set_flag)(int);
+	int   (*thread_clr_flag)(int);
+	void  (*at_fork)();
+};
+
+extern void _rtld_thread_init(struct RtldLockInfo *);
+
+#ifdef IN_RTLD
+
+struct rtld_lock;
+typedef struct rtld_lock *rtld_lock_t;
+
+extern rtld_lock_t	rtld_bind_lock;
+extern rtld_lock_t	rtld_libc_lock;
+
+int	rlock_acquire(rtld_lock_t);
+int 	wlock_acquire(rtld_lock_t);
+void	rlock_release(rtld_lock_t, int);
+void	wlock_release(rtld_lock_t, int);
+
+#endif	/* IN_RTLD */
+
+#endif