1#include "stdio_impl.h"
2#include <stdlib.h>
3#include <sys/ioctl.h>
4#include <fcntl.h>
5#include <errno.h>
6#include <string.h>
7
8FILE *__fdopen(int fd, const char *mode)
9{
10	FILE *f;
11	struct winsize wsz;
12
13	/* Check for valid initial mode character */
14	if (!strchr("rwa", *mode)) {
15		errno = EINVAL;
16		return 0;
17	}
18
19	/* Allocate FILE+buffer or fail */
20	if (!(f=malloc(sizeof *f + UNGET + BUFSIZ))) return 0;
21
22	/* Zero-fill only the struct, not the buffer */
23	memset(f, 0, sizeof *f);
24
25	/* Impose mode restrictions */
26	if (!strchr(mode, '+')) f->flags = (*mode == 'r') ? F_NOWR : F_NORD;
27
28	/* Apply close-on-exec flag */
29	if (strchr(mode, 'e')) __syscall(SYS_fcntl, fd, F_SETFD, FD_CLOEXEC);
30
31	/* Set append mode on fd if opened for append */
32	if (*mode == 'a') {
33		int flags = __syscall(SYS_fcntl, fd, F_GETFL);
34		if (!(flags & O_APPEND))
35			__syscall(SYS_fcntl, fd, F_SETFL, flags | O_APPEND);
36		f->flags |= F_APP;
37	}
38
39	f->fd = fd;
40	f->buf = (unsigned char *)f + sizeof *f + UNGET;
41	f->buf_size = BUFSIZ;
42
43	/* Activate line buffered mode for terminals */
44	f->lbf = EOF;
45	if (!(f->flags & F_NOWR) && !__syscall(SYS_ioctl, fd, TIOCGWINSZ, &wsz))
46		f->lbf = '\n';
47
48	/* Initialize op ptrs. No problem if some are unneeded. */
49	f->read = __stdio_read;
50	f->write = __stdio_write;
51	f->seek = __stdio_seek;
52	f->close = __stdio_close;
53
54	if (!libc.threaded) f->lock = -1;
55
56	/* Add new FILE to open file list */
57	return __ofl_add(f);
58}
59
60weak_alias(__fdopen, fdopen);
61