1#include "stdio_impl.h" 2#include <sys/uio.h> 3 4size_t __stdio_read(FILE *f, unsigned char *buf, size_t len) 5{ 6 struct iovec iov[2] = { 7 { .iov_base = buf, .iov_len = len - !!f->buf_size }, 8 { .iov_base = f->buf, .iov_len = f->buf_size } 9 }; 10 ssize_t cnt; 11 12 cnt = syscall(SYS_readv, f->fd, iov, 2); 13 if (cnt <= 0) { 14 f->flags |= F_EOF ^ ((F_ERR^F_EOF) & cnt); 15 return cnt; 16 } 17 if (cnt <= iov[0].iov_len) return cnt; 18 cnt -= iov[0].iov_len; 19 f->rpos = f->buf; 20 f->rend = f->buf + cnt; 21 if (f->buf_size) buf[len-1] = *f->rpos++; 22 return len; 23} 24