reactos/lib/sdk/crt/setjmp/i386/setjmp.s

   1 /*
   2  * COPYRIGHT:         See COPYING in the top level directory
   3  * PROJECT:           ReactOS system libraries
   4  * PURPOSE:           Implementation of _setjmp/longjmp
   5  * FILE:              lib/sdk/crt/setjmp/i386/setjmp.s
   6  * PROGRAMMER:        Ge van Geldorp (ge@gse.nl)
   7  * NOTES:             Implementation is not complete, see Wine source for a more
   8  *                    complete implementation
   9  */
  10
  11 #include <asm.inc>
  12
  13 #define JB_BP  0
  14 #define JB_BX  1
  15 #define JB_DI  2
  16 #define JB_SI  3
  17 #define JB_SP  4
  18 #define JB_IP  5
  19
  20 #define PCOFF  0
  21
  22 #define JMPBUF 4
  23
  24 .code
  25 /*
  26  * int
  27  * _setjmp(jmp_buf env);
  28  *
  29  * Parameters:
  30  *   [ESP+04h] - jmp_buf env
  31  * Registers:
  32  *   None
  33  * Returns:
  34  *   0
  35  * Notes:
  36  *   Sets up the jmp_buf
  37  */
  38 PUBLIC __setjmp
  39 __setjmp:
  40     xor eax, eax
  41     mov edx, JMPBUF[esp]
  42
  43     /* Save registers.  */
  44     mov [edx + JB_BP*4], ebp /* Save caller's frame pointer.  */
  45     mov [edx + JB_BX*4], ebx
  46     mov [edx + JB_DI*4], edi
  47     mov [edx + JB_SI*4], esi
  48     lea ecx, JMPBUF[esp]    /* Save SP as it will be after we return.  */
  49     mov [edx + JB_SP*4], ecx
  50     mov ecx, PCOFF[esp]     /* Save PC we are returning to now.  */
  51     mov [edx + JB_IP*4], ecx
  52     ret
  53
  54 /*
  55  * int
  56  * _setjmp3(jmp_buf env, int nb_args, ...);
  57  *
  58  * Parameters:
  59  *   [ESP+04h] - jmp_buf env
  60  * Registers:
  61  *   None
  62  * Returns:
  63  *   0
  64  * Notes:
  65  *   Sets up the jmp_buf
  66  */
  67 PUBLIC __setjmp3
  68 __setjmp3:
  69     xor eax, eax
  70     mov edx, JMPBUF[esp]
  71
  72     /* Save registers.  */
  73     mov [edx + JB_BP*4], ebp /* Save caller's frame pointer.  */
  74     mov [edx + JB_BX*4], ebx
  75     mov [edx + JB_DI*4], edi
  76     mov [edx + JB_SI*4], esi
  77     lea ecx, JMPBUF[esp]    /* Save SP as it will be after we return.  */
  78     mov [edx + JB_SP*4], ecx
  79     mov ecx, PCOFF[esp]     /* Save PC we are returning to now.  */
  80     mov [edx + JB_IP*4], ecx
  81     ret
  82
  83 /*
  84  * void
  85  * longjmp(jmp_buf env, int value);
  86  *
  87  * Parameters:
  88  *   [ESP+04h] - jmp_buf setup by _setjmp
  89  *   [ESP+08h] - int     value to return
  90  * Registers:
  91  *   None
  92  * Returns:
  93  *   Doesn't return
  94  * Notes:
  95  *   Non-local goto
  96  */
  97 PUBLIC _longjmp
  98 _longjmp:
  99     mov ecx, JMPBUF[esp]   /* User's jmp_buf in %ecx.  */
 100
 101     mov eax, [esp + 8]      /* Second argument is return value.  */
 102     /* Save the return address now.  */
 103     mov edx, [ecx + JB_IP*4]
 104     /* Restore registers.  */
 105     mov ebp, [ecx + JB_BP*4]
 106     mov ebx, [ecx + JB_BX*4]
 107     mov edi, [ecx + JB_DI*4]
 108     mov esi, [ecx + JB_SI*4]
 109     mov esp, [ecx + JB_SP*4]
 110     /* Jump to saved PC.  */
 111     jmp edx
 112
 113 END