diff options
Diffstat (limited to 'tools/include/nolibc/arch-i386.h')
| -rw-r--r-- | tools/include/nolibc/arch-i386.h | 60 |
1 files changed, 30 insertions, 30 deletions
diff --git a/tools/include/nolibc/arch-i386.h b/tools/include/nolibc/arch-i386.h index d7e7212346e2..e8d0cf545bf1 100644 --- a/tools/include/nolibc/arch-i386.h +++ b/tools/include/nolibc/arch-i386.h @@ -7,18 +7,6 @@ #ifndef _NOLIBC_ARCH_I386_H #define _NOLIBC_ARCH_I386_H -/* O_* macros for fcntl/open are architecture-specific */ -#define O_RDONLY 0 -#define O_WRONLY 1 -#define O_RDWR 2 -#define O_CREAT 0x40 -#define O_EXCL 0x80 -#define O_NOCTTY 0x100 -#define O_TRUNC 0x200 -#define O_APPEND 0x400 -#define O_NONBLOCK 0x800 -#define O_DIRECTORY 0x10000 - /* The struct returned by the stat() syscall, 32-bit only, the syscall returns * exactly 56 bytes (stops before the unused array). */ @@ -190,6 +178,9 @@ struct sys_stat_struct { _eax; \ }) +char **environ __attribute__((weak)); +const unsigned long *_auxv __attribute__((weak)); + /* startup code */ /* * i386 System V ABI mandates: @@ -197,23 +188,32 @@ struct sys_stat_struct { * 2) The deepest stack frame should be set to zero * */ -__asm__ (".section .text\n" - ".weak _start\n" - "_start:\n" - "pop %eax\n" // argc (first arg, %eax) - "mov %esp, %ebx\n" // argv[] (second arg, %ebx) - "lea 4(%ebx,%eax,4),%ecx\n" // then a NULL then envp (third arg, %ecx) - "xor %ebp, %ebp\n" // zero the stack frame - "and $-16, %esp\n" // x86 ABI : esp must be 16-byte aligned before - "sub $4, %esp\n" // the call instruction (args are aligned) - "push %ecx\n" // push all registers on the stack so that we - "push %ebx\n" // support both regparm and plain stack modes - "push %eax\n" - "call main\n" // main() returns the status code in %eax - "mov %eax, %ebx\n" // retrieve exit code (32-bit int) - "movl $1, %eax\n" // NR_exit == 1 - "int $0x80\n" // exit now - "hlt\n" // ensure it does not - ""); +void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void) +{ + __asm__ volatile ( + "pop %eax\n" // argc (first arg, %eax) + "mov %esp, %ebx\n" // argv[] (second arg, %ebx) + "lea 4(%ebx,%eax,4),%ecx\n" // then a NULL then envp (third arg, %ecx) + "mov %ecx, environ\n" // save environ + "xor %ebp, %ebp\n" // zero the stack frame + "mov %ecx, %edx\n" // search for auxv (follows NULL after last env) + "0:\n" + "add $4, %edx\n" // search for auxv using edx, it follows the + "cmp -4(%edx), %ebp\n" // ... NULL after last env (ebp is zero here) + "jnz 0b\n" + "mov %edx, _auxv\n" // save it into _auxv + "and $-16, %esp\n" // x86 ABI : esp must be 16-byte aligned before + "sub $4, %esp\n" // the call instruction (args are aligned) + "push %ecx\n" // push all registers on the stack so that we + "push %ebx\n" // support both regparm and plain stack modes + "push %eax\n" + "call main\n" // main() returns the status code in %eax + "mov %eax, %ebx\n" // retrieve exit code (32-bit int) + "movl $1, %eax\n" // NR_exit == 1 + "int $0x80\n" // exit now + "hlt\n" // ensure it does not + ); + __builtin_unreachable(); +} #endif // _NOLIBC_ARCH_I386_H |