diff options
Diffstat (limited to 'arch/um/os-Linux/file.c')
| -rw-r--r-- | arch/um/os-Linux/file.c | 698 |
1 files changed, 698 insertions, 0 deletions
diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c new file mode 100644 index 000000000..e4421dbc4 --- /dev/null +++ b/arch/um/os-Linux/file.c @@ -0,0 +1,698 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) + */ + +#include <stdio.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include <fcntl.h> +#include <signal.h> +#include <linux/falloc.h> +#include <sys/ioctl.h> +#include <sys/mount.h> +#include <sys/socket.h> +#include <sys/stat.h> +#include <sys/sysmacros.h> +#include <sys/un.h> +#include <sys/types.h> +#include <sys/eventfd.h> +#include <poll.h> +#include <os.h> + +static void copy_stat(struct uml_stat *dst, const struct stat64 *src) +{ + *dst = ((struct uml_stat) { + .ust_dev = src->st_dev, /* device */ + .ust_ino = src->st_ino, /* inode */ + .ust_mode = src->st_mode, /* protection */ + .ust_nlink = src->st_nlink, /* number of hard links */ + .ust_uid = src->st_uid, /* user ID of owner */ + .ust_gid = src->st_gid, /* group ID of owner */ + .ust_size = src->st_size, /* total size, in bytes */ + .ust_blksize = src->st_blksize, /* blocksize for filesys I/O */ + .ust_blocks = src->st_blocks, /* number of blocks allocated */ + .ust_atime = src->st_atime, /* time of last access */ + .ust_mtime = src->st_mtime, /* time of last modification */ + .ust_ctime = src->st_ctime, /* time of last change */ + }); +} + +int os_stat_fd(const int fd, struct uml_stat *ubuf) +{ + struct stat64 sbuf; + int err; + + CATCH_EINTR(err = fstat64(fd, &sbuf)); + if (err < 0) + return -errno; + + if (ubuf != NULL) + copy_stat(ubuf, &sbuf); + return err; +} + +int os_stat_file(const char *file_name, struct uml_stat *ubuf) +{ + struct stat64 sbuf; + int err; + + CATCH_EINTR(err = stat64(file_name, &sbuf)); + if (err < 0) + return -errno; + + if (ubuf != NULL) + copy_stat(ubuf, &sbuf); + return err; +} + +int os_access(const char *file, int mode) +{ + int amode, err; + + amode = (mode & OS_ACC_R_OK ? R_OK : 0) | + (mode & OS_ACC_W_OK ? W_OK : 0) | + (mode & OS_ACC_X_OK ? X_OK : 0) | + (mode & OS_ACC_F_OK ? F_OK : 0); + + err = access(file, amode); + if (err < 0) + return -errno; + + return 0; +} + +/* FIXME? required only by hostaudio (because it passes ioctls verbatim) */ +int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg) +{ + int err; + + err = ioctl(fd, cmd, arg); + if (err < 0) + return -errno; + + return err; +} + +/* FIXME: ensure namebuf in os_get_if_name is big enough */ +int os_get_ifname(int fd, char* namebuf) +{ + if (ioctl(fd, SIOCGIFNAME, namebuf) < 0) + return -errno; + + return 0; +} + +int os_set_slip(int fd) +{ + int disc, sencap; + + disc = N_SLIP; + if (ioctl(fd, TIOCSETD, &disc) < 0) + return -errno; + + sencap = 0; + if (ioctl(fd, SIOCSIFENCAP, &sencap) < 0) + return -errno; + + return 0; +} + +int os_mode_fd(int fd, int mode) +{ + int err; + + CATCH_EINTR(err = fchmod(fd, mode)); + if (err < 0) + return -errno; + + return 0; +} + +int os_file_type(char *file) +{ + struct uml_stat buf; + int err; + + err = os_stat_file(file, &buf); + if (err < 0) + return err; + + if (S_ISDIR(buf.ust_mode)) + return OS_TYPE_DIR; + else if (S_ISLNK(buf.ust_mode)) + return OS_TYPE_SYMLINK; + else if (S_ISCHR(buf.ust_mode)) + return OS_TYPE_CHARDEV; + else if (S_ISBLK(buf.ust_mode)) + return OS_TYPE_BLOCKDEV; + else if (S_ISFIFO(buf.ust_mode)) + return OS_TYPE_FIFO; + else if (S_ISSOCK(buf.ust_mode)) + return OS_TYPE_SOCK; + else return OS_TYPE_FILE; +} + +int os_file_mode(const char *file, struct openflags *mode_out) +{ + int err; + + *mode_out = OPENFLAGS(); + + err = access(file, W_OK); + if (err && (errno != EACCES)) + return -errno; + else if (!err) + *mode_out = of_write(*mode_out); + + err = access(file, R_OK); + if (err && (errno != EACCES)) + return -errno; + else if (!err) + *mode_out = of_read(*mode_out); + + return err; +} + +int os_open_file(const char *file, struct openflags flags, int mode) +{ + int fd, err, f = 0; + + if (flags.r && flags.w) + f = O_RDWR; + else if (flags.r) + f = O_RDONLY; + else if (flags.w) + f = O_WRONLY; + else f = 0; + + if (flags.s) + f |= O_SYNC; + if (flags.c) + f |= O_CREAT; + if (flags.t) + f |= O_TRUNC; + if (flags.e) + f |= O_EXCL; + if (flags.a) + f |= O_APPEND; + + fd = open64(file, f, mode); + if (fd < 0) + return -errno; + + if (flags.cl && fcntl(fd, F_SETFD, 1)) { + err = -errno; + close(fd); + return err; + } + + return fd; +} + +int os_connect_socket(const char *name) +{ + struct sockaddr_un sock; + int fd, err; + + sock.sun_family = AF_UNIX; + snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name); + + fd = socket(AF_UNIX, SOCK_STREAM, 0); + if (fd < 0) { + err = -errno; + goto out; + } + + err = connect(fd, (struct sockaddr *) &sock, sizeof(sock)); + if (err) { + err = -errno; + goto out_close; + } + + return fd; + +out_close: + close(fd); +out: + return err; +} + +void os_close_file(int fd) +{ + close(fd); +} +int os_fsync_file(int fd) +{ + if (fsync(fd) < 0) + return -errno; + return 0; +} + +int os_seek_file(int fd, unsigned long long offset) +{ + unsigned long long actual; + + actual = lseek64(fd, offset, SEEK_SET); + if (actual != offset) + return -errno; + return 0; +} + +int os_read_file(int fd, void *buf, int len) +{ + int n = read(fd, buf, len); + + if (n < 0) + return -errno; + return n; +} + +int os_pread_file(int fd, void *buf, int len, unsigned long long offset) +{ + int n = pread(fd, buf, len, offset); + + if (n < 0) + return -errno; + return n; +} + +int os_write_file(int fd, const void *buf, int len) +{ + int n = write(fd, (void *) buf, len); + + if (n < 0) + return -errno; + return n; +} + +int os_sync_file(int fd) +{ + int n = fdatasync(fd); + + if (n < 0) + return -errno; + return n; +} + +int os_pwrite_file(int fd, const void *buf, int len, unsigned long long offset) +{ + int n = pwrite(fd, (void *) buf, len, offset); + + if (n < 0) + return -errno; + return n; +} + + +int os_file_size(const char *file, unsigned long long *size_out) +{ + struct uml_stat buf; + int err; + + err = os_stat_file(file, &buf); + if (err < 0) { + printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file, + -err); + return err; + } + + if (S_ISBLK(buf.ust_mode)) { + int fd; + long blocks; + + fd = open(file, O_RDONLY, 0); + if (fd < 0) { + err = -errno; + printk(UM_KERN_ERR "Couldn't open \"%s\", " + "errno = %d\n", file, errno); + return err; + } + if (ioctl(fd, BLKGETSIZE, &blocks) < 0) { + err = -errno; + printk(UM_KERN_ERR "Couldn't get the block size of " + "\"%s\", errno = %d\n", file, errno); + close(fd); + return err; + } + *size_out = ((long long) blocks) * 512; + close(fd); + } + else *size_out = buf.ust_size; + + return 0; +} + +int os_file_modtime(const char *file, long long *modtime) +{ + struct uml_stat buf; + int err; + + err = os_stat_file(file, &buf); + if (err < 0) { + printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file, + -err); + return err; + } + + *modtime = buf.ust_mtime; + return 0; +} + +int os_set_exec_close(int fd) +{ + int err; + + CATCH_EINTR(err = fcntl(fd, F_SETFD, FD_CLOEXEC)); + + if (err < 0) + return -errno; + return err; +} + +int os_pipe(int *fds, int stream, int close_on_exec) +{ + int err, type = stream ? SOCK_STREAM : SOCK_DGRAM; + + err = socketpair(AF_UNIX, type, 0, fds); + if (err < 0) + return -errno; + + if (!close_on_exec) + return 0; + + err = os_set_exec_close(fds[0]); + if (err < 0) + goto error; + + err = os_set_exec_close(fds[1]); + if (err < 0) + goto error; + + return 0; + + error: + printk(UM_KERN_ERR "os_pipe : Setting FD_CLOEXEC failed, err = %d\n", + -err); + close(fds[1]); + close(fds[0]); + return err; +} + +int os_set_fd_async(int fd) +{ + int err, flags; + + flags = fcntl(fd, F_GETFL); + if (flags < 0) + return -errno; + + flags |= O_ASYNC | O_NONBLOCK; + if (fcntl(fd, F_SETFL, flags) < 0) { + err = -errno; + printk(UM_KERN_ERR "os_set_fd_async : failed to set O_ASYNC " + "and O_NONBLOCK on fd # %d, errno = %d\n", fd, errno); + return err; + } + + if ((fcntl(fd, F_SETSIG, SIGIO) < 0) || + (fcntl(fd, F_SETOWN, os_getpid()) < 0)) { + err = -errno; + printk(UM_KERN_ERR "os_set_fd_async : Failed to fcntl F_SETOWN " + "(or F_SETSIG) fd %d, errno = %d\n", fd, errno); + return err; + } + + return 0; +} + +int os_clear_fd_async(int fd) +{ + int flags; + + flags = fcntl(fd, F_GETFL); + if (flags < 0) + return -errno; + + flags &= ~(O_ASYNC | O_NONBLOCK); + if (fcntl(fd, F_SETFL, flags) < 0) + return -errno; + return 0; +} + +int os_set_fd_block(int fd, int blocking) +{ + int flags; + + flags = fcntl(fd, F_GETFL); + if (flags < 0) + return -errno; + + if (blocking) + flags &= ~O_NONBLOCK; + else + flags |= O_NONBLOCK; + + if (fcntl(fd, F_SETFL, flags) < 0) + return -errno; + + return 0; +} + +int os_accept_connection(int fd) +{ + int new; + + new = accept(fd, NULL, 0); + if (new < 0) + return -errno; + return new; +} + +#ifndef SHUT_RD +#define SHUT_RD 0 +#endif + +#ifndef SHUT_WR +#define SHUT_WR 1 +#endif + +#ifndef SHUT_RDWR +#define SHUT_RDWR 2 +#endif + +int os_shutdown_socket(int fd, int r, int w) +{ + int what, err; + + if (r && w) + what = SHUT_RDWR; + else if (r) + what = SHUT_RD; + else if (w) + what = SHUT_WR; + else + return -EINVAL; + + err = shutdown(fd, what); + if (err < 0) + return -errno; + return 0; +} + +int os_rcv_fd(int fd, int *helper_pid_out) +{ + int new, n; + char buf[CMSG_SPACE(sizeof(new))]; + struct msghdr msg; + struct cmsghdr *cmsg; + struct iovec iov; + + msg.msg_name = NULL; + msg.msg_namelen = 0; + iov = ((struct iovec) { .iov_base = helper_pid_out, + .iov_len = sizeof(*helper_pid_out) }); + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_control = buf; + msg.msg_controllen = sizeof(buf); + msg.msg_flags = 0; + + n = recvmsg(fd, &msg, 0); + if (n < 0) + return -errno; + else if (n != iov.iov_len) + *helper_pid_out = -1; + + cmsg = CMSG_FIRSTHDR(&msg); + if (cmsg == NULL) { + printk(UM_KERN_ERR "rcv_fd didn't receive anything, " + "error = %d\n", errno); + return -1; + } + if ((cmsg->cmsg_level != SOL_SOCKET) || + (cmsg->cmsg_type != SCM_RIGHTS)) { + printk(UM_KERN_ERR "rcv_fd didn't receive a descriptor\n"); + return -1; + } + + new = ((int *) CMSG_DATA(cmsg))[0]; + return new; +} + +int os_create_unix_socket(const char *file, int len, int close_on_exec) +{ + struct sockaddr_un addr; + int sock, err; + + sock = socket(PF_UNIX, SOCK_DGRAM, 0); + if (sock < 0) + return -errno; + + if (close_on_exec) { + err = os_set_exec_close(sock); + if (err < 0) + printk(UM_KERN_ERR "create_unix_socket : " + "close_on_exec failed, err = %d", -err); + } + + addr.sun_family = AF_UNIX; + + snprintf(addr.sun_path, len, "%s", file); + + err = bind(sock, (struct sockaddr *) &addr, sizeof(addr)); + if (err < 0) + return -errno; + + return sock; +} + +void os_flush_stdout(void) +{ + fflush(stdout); +} + +int os_lock_file(int fd, int excl) +{ + int type = excl ? F_WRLCK : F_RDLCK; + struct flock lock = ((struct flock) { .l_type = type, + .l_whence = SEEK_SET, + .l_start = 0, + .l_len = 0 } ); + int err, save; + + err = fcntl(fd, F_SETLK, &lock); + if (!err) + goto out; + + save = -errno; + err = fcntl(fd, F_GETLK, &lock); + if (err) { + err = -errno; + goto out; + } + + printk(UM_KERN_ERR "F_SETLK failed, file already locked by pid %d\n", + lock.l_pid); + err = save; + out: + return err; +} + +unsigned os_major(unsigned long long dev) +{ + return major(dev); +} + +unsigned os_minor(unsigned long long dev) +{ + return minor(dev); +} + +unsigned long long os_makedev(unsigned major, unsigned minor) +{ + return makedev(major, minor); +} + +int os_falloc_punch(int fd, unsigned long long offset, int len) +{ + int n = fallocate(fd, FALLOC_FL_PUNCH_HOLE|FALLOC_FL_KEEP_SIZE, offset, len); + + if (n < 0) + return -errno; + return n; +} + +int os_eventfd(unsigned int initval, int flags) +{ + int fd = eventfd(initval, flags); + + if (fd < 0) + return -errno; + return fd; +} + +int os_sendmsg_fds(int fd, const void *buf, unsigned int len, const int *fds, + unsigned int fds_num) +{ + struct iovec iov = { + .iov_base = (void *) buf, + .iov_len = len, + }; + union { + char control[CMSG_SPACE(sizeof(*fds) * OS_SENDMSG_MAX_FDS)]; + struct cmsghdr align; + } u; + unsigned int fds_size = sizeof(*fds) * fds_num; + struct msghdr msg = { + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = u.control, + .msg_controllen = CMSG_SPACE(fds_size), + }; + struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); + int err; + + if (fds_num > OS_SENDMSG_MAX_FDS) + return -EINVAL; + memset(u.control, 0, sizeof(u.control)); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + cmsg->cmsg_len = CMSG_LEN(fds_size); + memcpy(CMSG_DATA(cmsg), fds, fds_size); + err = sendmsg(fd, &msg, 0); + + if (err < 0) + return -errno; + return err; +} + +int os_poll(unsigned int n, const int *fds) +{ + /* currently need 2 FDs at most so avoid dynamic allocation */ + struct pollfd pollfds[2] = {}; + unsigned int i; + int ret; + + if (n > ARRAY_SIZE(pollfds)) + return -EINVAL; + + for (i = 0; i < n; i++) { + pollfds[i].fd = fds[i]; + pollfds[i].events = POLLIN; + } + + ret = poll(pollfds, n, -1); + if (ret < 0) + return -errno; + + /* Return the index of the available FD */ + for (i = 0; i < n; i++) { + if (pollfds[i].revents) + return i; + } + + return -EIO; +} |