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 #include <pthread.h>
8 #include "libc.h"
9
__fdopen(int fd,const char * mode)10 FILE *__fdopen(int fd, const char *mode)
11 {
12 FILE *f;
13 struct winsize wsz;
14 pthread_mutex_t filelockinit = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
15
16 /* Check for valid initial mode character */
17 if (!strchr("rwa", *mode)) {
18 errno = EINVAL;
19 return 0;
20 }
21
22 /* Allocate FILE+buffer or fail */
23 if (!(f=malloc(sizeof *f + UNGET + BUFSIZ + sizeof(pthread_mutex_t)))) return 0;
24
25 /* Zero-fill only the struct, not the buffer */
26 memset(f, 0, sizeof *f);
27
28 /* Impose mode restrictions */
29 if (!strchr(mode, '+')) f->flags = (*mode == 'r') ? F_NOWR : F_NORD;
30
31 /* Apply close-on-exec flag */
32 if (strchr(mode, 'e')) fcntl(fd, F_SETFD, FD_CLOEXEC);
33
34 /* Set append mode on fd if opened for append */
35 if (*mode == 'a') {
36 int flags = fcntl(fd, F_GETFL);
37 if (!(flags & O_APPEND))
38 fcntl(fd, F_SETFL, flags | O_APPEND);
39 f->flags |= F_APP;
40 }
41
42 f->fd = fd;
43 f->buf = (unsigned char *)f + sizeof *f + UNGET;
44 f->buf_size = BUFSIZ;
45 f->lock = (pthread_mutex_t *)((unsigned char *)f + sizeof *f + UNGET + BUFSIZ);
46 memcpy(f->lock, &filelockinit, sizeof(pthread_mutex_t));
47
48 /* Activate line buffered mode for terminals */
49 f->lbf = EOF;
50 if (!(f->flags & F_NOWR) && !ioctl(fd, TIOCGWINSZ, &wsz))
51 f->lbf = '\n';
52
53 /* Initialize op ptrs. No problem if some are unneeded. */
54 f->read = __stdio_read;
55 f->write = __stdio_write;
56 f->seek = __stdio_seek;
57 f->close = __stdio_close;
58
59 /* Add new FILE to open file list */
60 return __ofl_add(f);
61 }
62
63 weak_alias(__fdopen, fdopen);
64