1 #include "stdio_impl.h"
2 #include <sys/uio.h>
3
__stdio_readx(FILE * f,unsigned char * buf,size_t len)4 size_t __stdio_readx(FILE *f, unsigned char *buf, size_t len)
5 {
6 ssize_t cnt = syscall(SYS_read, f->fd, buf, len);
7 if (cnt <= 0) {
8 f->flags |= cnt ? F_ERR : F_EOF;
9 return 0;
10 }
11 return cnt;
12 }
13
__stdio_read(FILE * f,unsigned char * buf,size_t len)14 size_t __stdio_read(FILE *f, unsigned char *buf, size_t len)
15 {
16 struct iovec iov_buf[2] = {
17 { .iov_base = buf, .iov_len = len - !!f->buf_size },
18 { .iov_base = f->buf, .iov_len = f->buf_size }
19 };
20 ssize_t cnt;
21
22 cnt = iov_buf[0].iov_len ? syscall(SYS_readv, f->fd, iov_buf, 2)
23 : syscall(SYS_read, f->fd, iov_buf[1].iov_base, iov_buf[1].iov_len);
24 if (cnt <= 0) {
25 f->flags |= cnt ? F_ERR : F_EOF;
26 return 0;
27 }
28 if (cnt <= iov_buf[0].iov_len) {
29 return cnt;
30 }
31 cnt -= iov_buf[0].iov_len;
32 f->rpos = f->buf;
33 f->rend = f->buf + cnt;
34 if (f->buf_size) buf[len-1] = *f->rpos++;
35 return len;
36 }
37