usr/src/lib/libc/i386/sys/sigprocmask.s

/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * William Jolitz.
 *
 * Redistribution and use in source and binary forms are permitted provided
 * that: (1) source distributions retain this entire copyright notice and
 * comment, and (2) distributions including binaries display the following
 * acknowledgement:  ``This product includes software developed by the
 * University of California, Berkeley and its contributors'' in the
 * documentation or other materials provided with the distribution and in
 * all advertising materials mentioning features or use of this software.
 * Neither the name of the University nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#if defined(SYSLIBC_SCCS) && !defined(lint)
        .asciz "@(#)sigprocmask.s       5.1 (Berkeley) 7/1/90"
#endif /* SYSLIBC_SCCS and not lint */

#include "SYS.h"

err:
        jmp     cerror

ENTRY(sigprocmask)
        movl    8(%esp),%ecx            # fetch new sigset pointer
        cmpl    $0,(%ecx)               # check new sigset pointer
        jne     1f                      # if not null, indirect
/*      movl    $0,8(%esp)              # null mask pointer: block empty set */
        movl    $1,4(%esp)              # SIG_BLOCK
        jmp     2f
1:      movl    (%ecx),%ecx             # fetch indirect  ...
        movl    %ecx,8(%esp)            # to new mask arg
2:      movl    $ SYS_sigprocmask , %eax
        LCALL(0x7,0)
        jb      err
        movl    12(%esp),%ecx           # fetch old mask requested
        cmpl    $0,%ecx                 # test if old mask requested
        je      out
        movl    %eax,(%ecx)             # store old mask
out:
        xorl    %eax,%eax
        ret