紧急求教：BSD下面的汇编

weixin_38059788 2006-11-21 12:24:36

项目就要到期了，结果，别人的代码还没有看懂，请各位大虾帮帮忙：
下面的代码中，我对汇编部分不懂。请你们指点，在线等：

再 laio_api.c中：
int
laio_syscall(int number, ...)
{
      if (!_setjmp(sched_data.env)) {
            assert(current_thread);
            sched_data.mb.km_curthread = current_thread;
            thread_desc = current_thread;
            //rv = syscall(number, arg_list);
            //the asm code here
            {asm (
                     " \
                              pop %ecx; \
                              pop %eax; \
                              push %ecx; \
                              int $0x80; \
                              push %ecx; \
                              jb 1f; \
                              jmp 2f; \
                     1: \
                              pushl %ebx; \
                              call 1f; \
                     1: \
                              popl %ebx; \
                              addl $_GLOBAL_OFFSET_TABLE_+[.-1b],%ebx; \
                              jmp .cerror@PLT; \
                     2: \
                     ");
            }
            sched_data.mb.km_curthread = NULL;
            thread_desc = (void *) 0;
            asm("ret");
            assert(0);
      }
      else {
            laio_desc_bg = thread_desc;
            errno = EINPROGRESS;
            return (-1);
      }

      /* does not come here */
      assert(0);
      return (0);
}

在 laio_syscall.S中
/* $Id: laio_syscall.S,v 1.4 2004/01/13 00:18:26 anupamc Exp $ */
/*
.LC0:
      .string "env = %p\n"
*/
      .text
      .p2align 2,,3
.globl laio_syscall
      .type laio_syscall, @function
laio_syscall:
/*
      pushl $sched_data+96
      pushl $.LC0
      call printf
      addl $8, %esp
*/
      pushl $sched_data+96
      call _setjmp
      addl $4, %esp
      testl %eax, %eax
      jne    .L2
      movl current_thread, %eax
      movl %eax, sched_data+4
      movl (%esp), %eax
      movl %eax, foo
      movl $.L1, (%esp)
      jmp    syscall
.L1:
      movl $0, sched_data+4
.L3:
      jmp    *foo
.L2:
      call __error
      movl $36, (%eax)
      movl $-1, %eax
      jmp    .L3
      .size laio_syscall, .-laio_syscall

很着急，多谢了。 [ 本帖最后由 ericazhangjun 于 2006-11-21 13:05 编辑 ]

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