acrn-kernel/arch/um/os-Linux/file.c

681 lines
13 KiB
C

/*
* Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/uio.h>
#include "os.h"
#include "user.h"
#include "kern_util.h"
static void copy_stat(struct uml_stat *dst, 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;
do {
err = fstat64(fd, &sbuf);
} while((err < 0) && (errno == EINTR)) ;
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;
do {
err = stat64(file_name, &sbuf);
} while((err < 0) && (errno == EINTR)) ;
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);
}
void os_print_error(int error, const char* str)
{
errno = error < 0 ? -error : error;
perror(str);
}
/* 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);
}
int os_window_size(int fd, int *rows, int *cols)
{
struct winsize size;
if(ioctl(fd, TIOCGWINSZ, &size) < 0)
return(-errno);
*rows = size.ws_row;
*cols = size.ws_col;
return(0);
}
int os_new_tty_pgrp(int fd, int pid)
{
if(ioctl(fd, TIOCSCTTY, 0) < 0){
printk("TIOCSCTTY failed, errno = %d\n", errno);
return(-errno);
}
if(tcsetpgrp(fd, pid) < 0){
printk("tcsetpgrp failed, errno = %d\n", errno);
return(-errno);
}
return(0);
}
/* 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){
printk("Failed to set slip line discipline - "
"errno = %d\n", errno);
return(-errno);
}
sencap = 0;
if(ioctl(fd, SIOCSIFENCAP, &sencap) < 0){
printk("Failed to set slip encapsulation - "
"errno = %d\n", errno);
return(-errno);
}
return(0);
}
int os_set_owner(int fd, int pid)
{
if(fcntl(fd, F_SETOWN, pid) < 0){
int save_errno = errno;
if(fcntl(fd, F_GETOWN, 0) != pid)
return(-save_errno);
}
return(0);
}
/* FIXME? moved wholesale from sigio_user.c to get fcntls out of that file */
int os_sigio_async(int master, int slave)
{
int flags;
flags = fcntl(master, F_GETFL);
if(flags < 0) {
printk("fcntl F_GETFL failed, errno = %d\n", errno);
return(-errno);
}
if((fcntl(master, F_SETFL, flags | O_NONBLOCK | O_ASYNC) < 0) ||
(fcntl(master, F_SETOWN, os_getpid()) < 0)){
printk("fcntl F_SETFL or F_SETOWN failed, errno = %d\n",
errno);
return(-errno);
}
if((fcntl(slave, F_SETFL, flags | O_NONBLOCK) < 0)){
printk("fcntl F_SETFL failed, errno = %d\n", errno);
return(-errno);
}
return(0);
}
int os_mode_fd(int fd, int mode)
{
int err;
do {
err = fchmod(fd, mode);
} while((err < 0) && (errno==EINTR)) ;
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(char *file, struct openflags *mode_out)
{
int err;
*mode_out = OPENFLAGS();
err = os_access(file, OS_ACC_W_OK);
if((err < 0) && (err != -EACCES))
return(err);
*mode_out = of_write(*mode_out);
err = os_access(file, OS_ACC_R_OK);
if((err < 0) && (err != -EACCES))
return(err);
*mode_out = of_read(*mode_out);
return(0);
}
int os_open_file(char *file, struct openflags flags, int mode)
{
int fd, 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;
fd = open64(file, f, mode);
if(fd < 0)
return(-errno);
if(flags.cl && fcntl(fd, F_SETFD, 1)){
os_close_file(fd);
return(-errno);
}
return(fd);
}
int os_connect_socket(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)
return(fd);
err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
if(err)
return(-errno);
return(fd);
}
void os_close_file(int fd)
{
close(fd);
}
int os_seek_file(int fd, __u64 offset)
{
__u64 actual;
actual = lseek64(fd, offset, SEEK_SET);
if(actual != offset)
return(-errno);
return(0);
}
static int fault_buffer(void *start, int len,
int (*copy_proc)(void *addr, void *buf, int len))
{
int page = getpagesize(), i;
char c;
for(i = 0; i < len; i += page){
if((*copy_proc)(start + i, &c, sizeof(c)))
return(-EFAULT);
}
if((len % page) != 0){
if((*copy_proc)(start + len - 1, &c, sizeof(c)))
return(-EFAULT);
}
return(0);
}
static int file_io(int fd, void *buf, int len,
int (*io_proc)(int fd, void *buf, int len),
int (*copy_user_proc)(void *addr, void *buf, int len))
{
int n, err;
do {
n = (*io_proc)(fd, buf, len);
if((n < 0) && (errno == EFAULT)){
err = fault_buffer(buf, len, copy_user_proc);
if(err)
return(err);
n = (*io_proc)(fd, buf, len);
}
} while((n < 0) && (errno == EINTR));
if(n < 0)
return(-errno);
return(n);
}
int os_read_file(int fd, void *buf, int len)
{
return(file_io(fd, buf, len, (int (*)(int, void *, int)) read,
copy_from_user_proc));
}
int os_write_file(int fd, const void *buf, int len)
{
return(file_io(fd, (void *) buf, len,
(int (*)(int, void *, int)) write, copy_to_user_proc));
}
int os_file_size(char *file, long long *size_out)
{
struct uml_stat buf;
int err;
err = os_stat_file(file, &buf);
if(err < 0){
printk("Couldn't stat \"%s\" : err = %d\n", file, -err);
return(err);
}
if(S_ISBLK(buf.ust_mode)){
int fd, blocks;
fd = os_open_file(file, of_read(OPENFLAGS()), 0);
if(fd < 0){
printk("Couldn't open \"%s\", errno = %d\n", file, -fd);
return(fd);
}
if(ioctl(fd, BLKGETSIZE, &blocks) < 0){
printk("Couldn't get the block size of \"%s\", "
"errno = %d\n", file, errno);
err = -errno;
os_close_file(fd);
return(err);
}
*size_out = ((long long) blocks) * 512;
os_close_file(fd);
return(0);
}
*size_out = buf.ust_size;
return(0);
}
int os_file_modtime(char *file, unsigned long *modtime)
{
struct uml_stat buf;
int err;
err = os_stat_file(file, &buf);
if(err < 0){
printk("Couldn't stat \"%s\" : err = %d\n", file, -err);
return(err);
}
*modtime = buf.ust_mtime;
return(0);
}
int os_get_exec_close(int fd, int* close_on_exec)
{
int ret;
do {
ret = fcntl(fd, F_GETFD);
} while((ret < 0) && (errno == EINTR)) ;
if(ret < 0)
return(-errno);
*close_on_exec = (ret&FD_CLOEXEC) ? 1 : 0;
return(ret);
}
int os_set_exec_close(int fd, int close_on_exec)
{
int flag, err;
if(close_on_exec) flag = FD_CLOEXEC;
else flag = 0;
do {
err = fcntl(fd, F_SETFD, flag);
} while((err < 0) && (errno == EINTR)) ;
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], 1);
if(err < 0)
goto error;
err = os_set_exec_close(fds[1], 1);
if(err < 0)
goto error;
return(0);
error:
printk("os_pipe : Setting FD_CLOEXEC failed, err = %d\n", -err);
os_close_file(fds[1]);
os_close_file(fds[0]);
return(err);
}
int os_set_fd_async(int fd, int owner)
{
/* XXX This should do F_GETFL first */
if(fcntl(fd, F_SETFL, O_ASYNC | O_NONBLOCK) < 0){
printk("os_set_fd_async : failed to set O_ASYNC and "
"O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
return(-errno);
}
#ifdef notdef
if(fcntl(fd, F_SETFD, 1) < 0){
printk("os_set_fd_async : Setting FD_CLOEXEC failed, "
"errno = %d\n", errno);
}
#endif
if((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
(fcntl(fd, F_SETOWN, owner) < 0)){
printk("os_set_fd_async : Failed to fcntl F_SETOWN "
"(or F_SETSIG) fd %d to pid %d, errno = %d\n", fd,
owner, errno);
return(-errno);
}
return(0);
}
int os_clear_fd_async(int fd)
{
int flags = fcntl(fd, F_GETFL);
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(blocking) flags &= ~O_NONBLOCK;
else flags |= O_NONBLOCK;
if(fcntl(fd, F_SETFL, flags) < 0){
printk("Failed to change blocking on fd # %d, errno = %d\n",
fd, errno);
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 {
printk("os_shutdown_socket : neither r or w was set\n");
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 != sizeof(iov.iov_len))
*helper_pid_out = -1;
cmsg = CMSG_FIRSTHDR(&msg);
if(cmsg == NULL){
printk("rcv_fd didn't receive anything, error = %d\n", errno);
return(-1);
}
if((cmsg->cmsg_level != SOL_SOCKET) ||
(cmsg->cmsg_type != SCM_RIGHTS)){
printk("rcv_fd didn't receive a descriptor\n");
return(-1);
}
new = ((int *) CMSG_DATA(cmsg))[0];
return(new);
}
int os_create_unix_socket(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){
printk("create_unix_socket - socket failed, errno = %d\n",
errno);
return(-errno);
}
if(close_on_exec) {
err = os_set_exec_close(sock, 1);
if(err < 0)
printk("create_unix_socket : close_on_exec failed, "
"err = %d", -err);
}
addr.sun_family = AF_UNIX;
/* XXX Be more careful about overflow */
snprintf(addr.sun_path, len, "%s", file);
err = bind(sock, (struct sockaddr *) &addr, sizeof(addr));
if (err < 0){
printk("create_listening_socket at '%s' - bind failed, "
"errno = %d\n", file, errno);
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("F_SETLK failed, file already locked by pid %d\n", lock.l_pid);
err = save;
out:
return(err);
}
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/