blob: 49d6f8de8171efa6d1195253acf6fee54464a3bf [file] [log] [blame]
* Generic syscall call.
* Upon entry:
* %eax: system call number - caller save
* %ebx: arg0 to system call - callee save
* %ecx: arg1 - caller save
* %edx: arg2 - caller save
* %esi: arg3 - callee save
* %edi: arg4 - callee save
* %ebp: arg5 - callee save
#include <sys/linux-syscalls.h>
.type syscall, @function
.globl syscall
.align 4
# Push the callee save registers.
push %ebx
push %esi
push %edi
push %ebp
# Load all the arguments from the calling frame.
# (Not all will be valid, depending on the syscall.)
mov 20(%esp),%eax
mov 24(%esp),%ebx
mov 28(%esp),%ecx
mov 32(%esp),%edx
mov 36(%esp),%esi
mov 40(%esp),%edi
mov 44(%esp),%ebp
# Make the system call.
int $0x80
# Error?
cmpl $-4095, %eax
jb 1f
# Yes, so set errno.
negl %eax
pushl %eax
call __set_errno
addl $4, %esp
orl $-1, %eax
# Restore the callee save registers.
pop %ebp
pop %edi
pop %esi
pop %ebx