xref: /openbmc/linux/arch/um/os-Linux/file.c (revision 7e6f7d24) 
1 /*
2  * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3  * Licensed under the GPL
4  */
5 
6 #include <stdio.h>
7 #include <unistd.h>
8 #include <errno.h>
9 #include <fcntl.h>
10 #include <signal.h>
11 #include <sys/ioctl.h>
12 #include <sys/mount.h>
13 #include <sys/socket.h>
14 #include <sys/stat.h>
15 #include <sys/sysmacros.h>
16 #include <sys/un.h>
17 #include <sys/types.h>
18 #include <os.h>
19 
20 static void copy_stat(struct uml_stat *dst, const struct stat64 *src)
21 {
22 	*dst = ((struct uml_stat) {
23 		.ust_dev     = src->st_dev,     /* device */
24 		.ust_ino     = src->st_ino,     /* inode */
25 		.ust_mode    = src->st_mode,    /* protection */
26 		.ust_nlink   = src->st_nlink,   /* number of hard links */
27 		.ust_uid     = src->st_uid,     /* user ID of owner */
28 		.ust_gid     = src->st_gid,     /* group ID of owner */
29 		.ust_size    = src->st_size,    /* total size, in bytes */
30 		.ust_blksize = src->st_blksize, /* blocksize for filesys I/O */
31 		.ust_blocks  = src->st_blocks,  /* number of blocks allocated */
32 		.ust_atime   = src->st_atime,   /* time of last access */
33 		.ust_mtime   = src->st_mtime,   /* time of last modification */
34 		.ust_ctime   = src->st_ctime,   /* time of last change */
35 	});
36 }
37 
38 int os_stat_fd(const int fd, struct uml_stat *ubuf)
39 {
40 	struct stat64 sbuf;
41 	int err;
42 
43 	CATCH_EINTR(err = fstat64(fd, &sbuf));
44 	if (err < 0)
45 		return -errno;
46 
47 	if (ubuf != NULL)
48 		copy_stat(ubuf, &sbuf);
49 	return err;
50 }
51 
52 int os_stat_file(const char *file_name, struct uml_stat *ubuf)
53 {
54 	struct stat64 sbuf;
55 	int err;
56 
57 	CATCH_EINTR(err = stat64(file_name, &sbuf));
58 	if (err < 0)
59 		return -errno;
60 
61 	if (ubuf != NULL)
62 		copy_stat(ubuf, &sbuf);
63 	return err;
64 }
65 
66 int os_access(const char *file, int mode)
67 {
68 	int amode, err;
69 
70 	amode = (mode & OS_ACC_R_OK ? R_OK : 0) |
71 		(mode & OS_ACC_W_OK ? W_OK : 0) |
72 		(mode & OS_ACC_X_OK ? X_OK : 0) |
73 		(mode & OS_ACC_F_OK ? F_OK : 0);
74 
75 	err = access(file, amode);
76 	if (err < 0)
77 		return -errno;
78 
79 	return 0;
80 }
81 
82 /* FIXME? required only by hostaudio (because it passes ioctls verbatim) */
83 int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg)
84 {
85 	int err;
86 
87 	err = ioctl(fd, cmd, arg);
88 	if (err < 0)
89 		return -errno;
90 
91 	return err;
92 }
93 
94 /* FIXME: ensure namebuf in os_get_if_name is big enough */
95 int os_get_ifname(int fd, char* namebuf)
96 {
97 	if (ioctl(fd, SIOCGIFNAME, namebuf) < 0)
98 		return -errno;
99 
100 	return 0;
101 }
102 
103 int os_set_slip(int fd)
104 {
105 	int disc, sencap;
106 
107 	disc = N_SLIP;
108 	if (ioctl(fd, TIOCSETD, &disc) < 0)
109 		return -errno;
110 
111 	sencap = 0;
112 	if (ioctl(fd, SIOCSIFENCAP, &sencap) < 0)
113 		return -errno;
114 
115 	return 0;
116 }
117 
118 int os_mode_fd(int fd, int mode)
119 {
120 	int err;
121 
122 	CATCH_EINTR(err = fchmod(fd, mode));
123 	if (err < 0)
124 		return -errno;
125 
126 	return 0;
127 }
128 
129 int os_file_type(char *file)
130 {
131 	struct uml_stat buf;
132 	int err;
133 
134 	err = os_stat_file(file, &buf);
135 	if (err < 0)
136 		return err;
137 
138 	if (S_ISDIR(buf.ust_mode))
139 		return OS_TYPE_DIR;
140 	else if (S_ISLNK(buf.ust_mode))
141 		return OS_TYPE_SYMLINK;
142 	else if (S_ISCHR(buf.ust_mode))
143 		return OS_TYPE_CHARDEV;
144 	else if (S_ISBLK(buf.ust_mode))
145 		return OS_TYPE_BLOCKDEV;
146 	else if (S_ISFIFO(buf.ust_mode))
147 		return OS_TYPE_FIFO;
148 	else if (S_ISSOCK(buf.ust_mode))
149 		return OS_TYPE_SOCK;
150 	else return OS_TYPE_FILE;
151 }
152 
153 int os_file_mode(const char *file, struct openflags *mode_out)
154 {
155 	int err;
156 
157 	*mode_out = OPENFLAGS();
158 
159 	err = access(file, W_OK);
160 	if (err && (errno != EACCES))
161 		return -errno;
162 	else if (!err)
163 		*mode_out = of_write(*mode_out);
164 
165 	err = access(file, R_OK);
166 	if (err && (errno != EACCES))
167 		return -errno;
168 	else if (!err)
169 		*mode_out = of_read(*mode_out);
170 
171 	return err;
172 }
173 
174 int os_open_file(const char *file, struct openflags flags, int mode)
175 {
176 	int fd, err, f = 0;
177 
178 	if (flags.r && flags.w)
179 		f = O_RDWR;
180 	else if (flags.r)
181 		f = O_RDONLY;
182 	else if (flags.w)
183 		f = O_WRONLY;
184 	else f = 0;
185 
186 	if (flags.s)
187 		f |= O_SYNC;
188 	if (flags.c)
189 		f |= O_CREAT;
190 	if (flags.t)
191 		f |= O_TRUNC;
192 	if (flags.e)
193 		f |= O_EXCL;
194 	if (flags.a)
195 		f |= O_APPEND;
196 
197 	fd = open64(file, f, mode);
198 	if (fd < 0)
199 		return -errno;
200 
201 	if (flags.cl && fcntl(fd, F_SETFD, 1)) {
202 		err = -errno;
203 		close(fd);
204 		return err;
205 	}
206 
207 	return fd;
208 }
209 
210 int os_connect_socket(const char *name)
211 {
212 	struct sockaddr_un sock;
213 	int fd, err;
214 
215 	sock.sun_family = AF_UNIX;
216 	snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);
217 
218 	fd = socket(AF_UNIX, SOCK_STREAM, 0);
219 	if (fd < 0) {
220 		err = -errno;
221 		goto out;
222 	}
223 
224 	err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
225 	if (err) {
226 		err = -errno;
227 		goto out_close;
228 	}
229 
230 	return fd;
231 
232 out_close:
233 	close(fd);
234 out:
235 	return err;
236 }
237 
238 void os_close_file(int fd)
239 {
240 	close(fd);
241 }
242 int os_fsync_file(int fd)
243 {
244 	if (fsync(fd) < 0)
245 	    return -errno;
246 	return 0;
247 }
248 
249 int os_seek_file(int fd, unsigned long long offset)
250 {
251 	unsigned long long actual;
252 
253 	actual = lseek64(fd, offset, SEEK_SET);
254 	if (actual != offset)
255 		return -errno;
256 	return 0;
257 }
258 
259 int os_read_file(int fd, void *buf, int len)
260 {
261 	int n = read(fd, buf, len);
262 
263 	if (n < 0)
264 		return -errno;
265 	return n;
266 }
267 
268 int os_pread_file(int fd, void *buf, int len, unsigned long long offset)
269 {
270 	int n = pread(fd, buf, len, offset);
271 
272 	if (n < 0)
273 		return -errno;
274 	return n;
275 }
276 
277 int os_write_file(int fd, const void *buf, int len)
278 {
279 	int n = write(fd, (void *) buf, len);
280 
281 	if (n < 0)
282 		return -errno;
283 	return n;
284 }
285 
286 int os_sync_file(int fd)
287 {
288 	int n = fsync(fd);
289 
290 	if (n < 0)
291 		return -errno;
292 	return n;
293 }
294 
295 int os_pwrite_file(int fd, const void *buf, int len, unsigned long long offset)
296 {
297 	int n = pwrite(fd, (void *) buf, len, offset);
298 
299 	if (n < 0)
300 		return -errno;
301 	return n;
302 }
303 
304 
305 int os_file_size(const char *file, unsigned long long *size_out)
306 {
307 	struct uml_stat buf;
308 	int err;
309 
310 	err = os_stat_file(file, &buf);
311 	if (err < 0) {
312 		printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
313 		       -err);
314 		return err;
315 	}
316 
317 	if (S_ISBLK(buf.ust_mode)) {
318 		int fd;
319 		long blocks;
320 
321 		fd = open(file, O_RDONLY, 0);
322 		if (fd < 0) {
323 			err = -errno;
324 			printk(UM_KERN_ERR "Couldn't open \"%s\", "
325 			       "errno = %d\n", file, errno);
326 			return err;
327 		}
328 		if (ioctl(fd, BLKGETSIZE, &blocks) < 0) {
329 			err = -errno;
330 			printk(UM_KERN_ERR "Couldn't get the block size of "
331 			       "\"%s\", errno = %d\n", file, errno);
332 			close(fd);
333 			return err;
334 		}
335 		*size_out = ((long long) blocks) * 512;
336 		close(fd);
337 	}
338 	else *size_out = buf.ust_size;
339 
340 	return 0;
341 }
342 
343 int os_file_modtime(const char *file, unsigned long *modtime)
344 {
345 	struct uml_stat buf;
346 	int err;
347 
348 	err = os_stat_file(file, &buf);
349 	if (err < 0) {
350 		printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
351 		       -err);
352 		return err;
353 	}
354 
355 	*modtime = buf.ust_mtime;
356 	return 0;
357 }
358 
359 int os_set_exec_close(int fd)
360 {
361 	int err;
362 
363 	CATCH_EINTR(err = fcntl(fd, F_SETFD, FD_CLOEXEC));
364 
365 	if (err < 0)
366 		return -errno;
367 	return err;
368 }
369 
370 int os_pipe(int *fds, int stream, int close_on_exec)
371 {
372 	int err, type = stream ? SOCK_STREAM : SOCK_DGRAM;
373 
374 	err = socketpair(AF_UNIX, type, 0, fds);
375 	if (err < 0)
376 		return -errno;
377 
378 	if (!close_on_exec)
379 		return 0;
380 
381 	err = os_set_exec_close(fds[0]);
382 	if (err < 0)
383 		goto error;
384 
385 	err = os_set_exec_close(fds[1]);
386 	if (err < 0)
387 		goto error;
388 
389 	return 0;
390 
391  error:
392 	printk(UM_KERN_ERR "os_pipe : Setting FD_CLOEXEC failed, err = %d\n",
393 	       -err);
394 	close(fds[1]);
395 	close(fds[0]);
396 	return err;
397 }
398 
399 int os_set_fd_async(int fd)
400 {
401 	int err, flags;
402 
403 	flags = fcntl(fd, F_GETFL);
404 	if (flags < 0)
405 		return -errno;
406 
407 	flags |= O_ASYNC | O_NONBLOCK;
408 	if (fcntl(fd, F_SETFL, flags) < 0) {
409 		err = -errno;
410 		printk(UM_KERN_ERR "os_set_fd_async : failed to set O_ASYNC "
411 		       "and O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
412 		return err;
413 	}
414 
415 	if ((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
416 	    (fcntl(fd, F_SETOWN, os_getpid()) < 0)) {
417 		err = -errno;
418 		printk(UM_KERN_ERR "os_set_fd_async : Failed to fcntl F_SETOWN "
419 		       "(or F_SETSIG) fd %d, errno = %d\n", fd, errno);
420 		return err;
421 	}
422 
423 	return 0;
424 }
425 
426 int os_clear_fd_async(int fd)
427 {
428 	int flags;
429 
430 	flags = fcntl(fd, F_GETFL);
431 	if (flags < 0)
432 		return -errno;
433 
434 	flags &= ~(O_ASYNC | O_NONBLOCK);
435 	if (fcntl(fd, F_SETFL, flags) < 0)
436 		return -errno;
437 	return 0;
438 }
439 
440 int os_set_fd_block(int fd, int blocking)
441 {
442 	int flags;
443 
444 	flags = fcntl(fd, F_GETFL);
445 	if (flags < 0)
446 		return -errno;
447 
448 	if (blocking)
449 		flags &= ~O_NONBLOCK;
450 	else
451 		flags |= O_NONBLOCK;
452 
453 	if (fcntl(fd, F_SETFL, flags) < 0)
454 		return -errno;
455 
456 	return 0;
457 }
458 
459 int os_accept_connection(int fd)
460 {
461 	int new;
462 
463 	new = accept(fd, NULL, 0);
464 	if (new < 0)
465 		return -errno;
466 	return new;
467 }
468 
469 #ifndef SHUT_RD
470 #define SHUT_RD 0
471 #endif
472 
473 #ifndef SHUT_WR
474 #define SHUT_WR 1
475 #endif
476 
477 #ifndef SHUT_RDWR
478 #define SHUT_RDWR 2
479 #endif
480 
481 int os_shutdown_socket(int fd, int r, int w)
482 {
483 	int what, err;
484 
485 	if (r && w)
486 		what = SHUT_RDWR;
487 	else if (r)
488 		what = SHUT_RD;
489 	else if (w)
490 		what = SHUT_WR;
491 	else
492 		return -EINVAL;
493 
494 	err = shutdown(fd, what);
495 	if (err < 0)
496 		return -errno;
497 	return 0;
498 }
499 
500 int os_rcv_fd(int fd, int *helper_pid_out)
501 {
502 	int new, n;
503 	char buf[CMSG_SPACE(sizeof(new))];
504 	struct msghdr msg;
505 	struct cmsghdr *cmsg;
506 	struct iovec iov;
507 
508 	msg.msg_name = NULL;
509 	msg.msg_namelen = 0;
510 	iov = ((struct iovec) { .iov_base  = helper_pid_out,
511 				.iov_len   = sizeof(*helper_pid_out) });
512 	msg.msg_iov = &iov;
513 	msg.msg_iovlen = 1;
514 	msg.msg_control = buf;
515 	msg.msg_controllen = sizeof(buf);
516 	msg.msg_flags = 0;
517 
518 	n = recvmsg(fd, &msg, 0);
519 	if (n < 0)
520 		return -errno;
521 	else if (n != iov.iov_len)
522 		*helper_pid_out = -1;
523 
524 	cmsg = CMSG_FIRSTHDR(&msg);
525 	if (cmsg == NULL) {
526 		printk(UM_KERN_ERR "rcv_fd didn't receive anything, "
527 		       "error = %d\n", errno);
528 		return -1;
529 	}
530 	if ((cmsg->cmsg_level != SOL_SOCKET) ||
531 	    (cmsg->cmsg_type != SCM_RIGHTS)) {
532 		printk(UM_KERN_ERR "rcv_fd didn't receive a descriptor\n");
533 		return -1;
534 	}
535 
536 	new = ((int *) CMSG_DATA(cmsg))[0];
537 	return new;
538 }
539 
540 int os_create_unix_socket(const char *file, int len, int close_on_exec)
541 {
542 	struct sockaddr_un addr;
543 	int sock, err;
544 
545 	sock = socket(PF_UNIX, SOCK_DGRAM, 0);
546 	if (sock < 0)
547 		return -errno;
548 
549 	if (close_on_exec) {
550 		err = os_set_exec_close(sock);
551 		if (err < 0)
552 			printk(UM_KERN_ERR "create_unix_socket : "
553 			       "close_on_exec failed, err = %d", -err);
554 	}
555 
556 	addr.sun_family = AF_UNIX;
557 
558 	snprintf(addr.sun_path, len, "%s", file);
559 
560 	err = bind(sock, (struct sockaddr *) &addr, sizeof(addr));
561 	if (err < 0)
562 		return -errno;
563 
564 	return sock;
565 }
566 
567 void os_flush_stdout(void)
568 {
569 	fflush(stdout);
570 }
571 
572 int os_lock_file(int fd, int excl)
573 {
574 	int type = excl ? F_WRLCK : F_RDLCK;
575 	struct flock lock = ((struct flock) { .l_type	= type,
576 					      .l_whence	= SEEK_SET,
577 					      .l_start	= 0,
578 					      .l_len	= 0 } );
579 	int err, save;
580 
581 	err = fcntl(fd, F_SETLK, &lock);
582 	if (!err)
583 		goto out;
584 
585 	save = -errno;
586 	err = fcntl(fd, F_GETLK, &lock);
587 	if (err) {
588 		err = -errno;
589 		goto out;
590 	}
591 
592 	printk(UM_KERN_ERR "F_SETLK failed, file already locked by pid %d\n",
593 	       lock.l_pid);
594 	err = save;
595  out:
596 	return err;
597 }
598 
599 unsigned os_major(unsigned long long dev)
600 {
601 	return major(dev);
602 }
603 
604 unsigned os_minor(unsigned long long dev)
605 {
606 	return minor(dev);
607 }
608 
609 unsigned long long os_makedev(unsigned major, unsigned minor)
610 {
611 	return makedev(major, minor);
612 }
613