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.
 *
 * %sccs.include.redist.c%
 */

#if defined(SYSLIBC_SCCS) && !defined(lint)
        .asciz "@(#)sigprocmask.s       5.2 (Berkeley) %G%"
#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