diff options
Diffstat (limited to 'ft_write.s')
| -rw-r--r-- | ft_write.s | 32 |
1 files changed, 30 insertions, 2 deletions
@@ -12,8 +12,36 @@ global ft_write -; int ft_write(int, const void*, size_t); +%define F_GETFD 1 +%define SYSCALL_WRITE 0x2000004 +%define SYSCALL_FCNTL 0x200005c + +; int ft_write(int rdi, const void *rsi, size_t rdx); ft_write: - mov rax, 0x2000004 + cmp rdx, 0 + je FT_WRITE_NO_SIZE + cmp rdi, 0 + jl FT_WRITE_ERROR ; fd < 0 + cmp rsi, 0 + je FT_WRITE_ERROR ; buf == NULL + + push rdx + push rsi + xor rsi, rsi + mov esi, F_GETFD + mov rax, SYSCALL_FCNTL + syscall + pop rsi + pop rdx + cmp eax, 0 + jne FT_WRITE_ERROR + + mov rax, SYSCALL_WRITE syscall ret +FT_WRITE_ERROR: + mov rax, -1 + ret +FT_WRITE_NO_SIZE: + mov rax, 0 + ret |