file.c 11 KB

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