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/
/ our buffer looks like:
/ eax,ebx,ecx,edx,esi,edi,esp,ebp,pc
/
/ _longjmp is called with two parameters: jmp_buf*,int
/ jmp_buf* is at 4(%esp), int is at 8(%esp)
/ retaddr is, of course, at (%esp)
.globl _longjmp
.globl longjmp
_longjmp:
longjmp:
movl 4(%esp), %ebx / address of buf
movl 8(%esp), %eax / store return value
movl 24(%ebx), %esp / restore stack
movl 32(%ebx), %edi
/ Next line sets up return address.
movl %edi, 0(%esp)
movl 8(%ebx), %ecx
movl 12(%ebx), %edx
movl 16(%ebx), %esi
movl 20(%ebx), %edi
movl 28(%ebx), %ebp
movl 4(%ebx), %ebx
testl %eax,%eax
jne bye
incl %eax / eax hold 0 if we are here
bye:
ret
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