haiku/src/kernel/core/fd.c
David Reid d2de8b3867 Include kerrors.h where it's required.
git-svn-id: file:///srv/svn/repos/haiku/trunk/current@105 a95241bf-73f2-0310-859d-f6bbb57e9c96
2002-07-11 22:21:56 +00:00

457 lines
8.5 KiB
C

/* fd.c
*
* Operations on file descriptors...
* see fd.h for the definitions
*
*/
#include <ktypes.h>
#include <OS.h>
#include <fd.h>
#include <vfs.h>
#include <Errors.h>
#include <debug.h>
#include <memheap.h>
#include <string.h>
#define CHECK_USER_ADDR(x) \
if ((addr)(x) >= KERNEL_BASE && (addr)(x) <= KERNEL_TOP) \
return EINVAL;
#define CHECK_SYS_ADDR(x) \
if ((addr)(x) < KERNEL_BASE && (addr)(x) >= KERNEL_TOP) \
return EINVAL;
#define PRINT(x) dprintf x
/*** General fd routines ***/
/** Allocates and initializes a new file_descriptor */
struct file_descriptor *
alloc_fd(void)
{
struct file_descriptor *f;
f = kmalloc(sizeof(struct file_descriptor));
if(f) {
f->vnode = NULL;
f->cookie = NULL;
f->ref_count = 1;
}
return f;
}
int
new_fd(struct io_context *ioctx, struct file_descriptor *f)
{
int fd = -1;
int i;
mutex_lock(&ioctx->io_mutex);
for (i = 0; i < ioctx->table_size; i++) {
if (!ioctx->fds[i]) {
fd = i;
break;
}
}
if (fd < 0) {
fd = EMFILE;
goto err;
}
ioctx->fds[fd] = f;
ioctx->num_used_fds++;
err:
mutex_unlock(&ioctx->io_mutex);
return fd;
}
void
put_fd(struct file_descriptor *f)
{
/* Run a cleanup (fd_free) routine if there is one and free structure, but only
* if we've just removed the final reference to it :)
*/
if (atomic_add(&f->ref_count, -1) == 1) {
if (f->ops->fd_free)
f->ops->fd_free(f);
kfree(f);
}
}
struct file_descriptor *
get_fd(struct io_context *ioctx, int fd)
{
struct file_descriptor *f;
mutex_lock(&ioctx->io_mutex);
if (fd >= 0 && fd < ioctx->table_size && ioctx->fds[fd]) {
// valid fd
f = ioctx->fds[fd];
atomic_add(&f->ref_count, 1);
} else {
f = NULL;
}
mutex_unlock(&ioctx->io_mutex);
return f;
}
void
remove_fd(struct io_context *ioctx, int fd)
{
struct file_descriptor *f;
mutex_lock(&ioctx->io_mutex);
if (fd >= 0 && fd < ioctx->table_size && ioctx->fds[fd]) {
// valid fd
f = ioctx->fds[fd];
ioctx->fds[fd] = NULL;
ioctx->num_used_fds--;
} else {
f = NULL;
}
mutex_unlock(&ioctx->io_mutex);
if (f)
put_fd(f);
}
// #pragma mark -
/*** USER routines ***/
ssize_t
user_read(int fd, void *buffer, off_t pos, size_t length)
{
struct file_descriptor *descriptor;
ssize_t retval;
/* This is a user_function, so abort if we have a kernel address */
CHECK_USER_ADDR(buffer)
descriptor = get_fd(get_current_io_context(false), fd);
if (!descriptor)
return EBADF;
if (descriptor->ops->fd_read) {
retval = descriptor->ops->fd_read(descriptor, buffer, pos, &length);
if (retval >= 0)
retval = (ssize_t)length;
} else
retval = EINVAL;
put_fd(descriptor);
return retval;
}
ssize_t
user_write(int fd, const void *buffer, off_t pos, size_t length)
{
struct file_descriptor *descriptor;
ssize_t retval = 0;
CHECK_USER_ADDR(buffer)
descriptor = get_fd(get_current_io_context(false), fd);
if (!descriptor)
return EBADF;
if (descriptor->ops->fd_write) {
retval = descriptor->ops->fd_write(descriptor, buffer, pos, &length);
if (retval >= 0)
retval = (ssize_t)length;
} else
retval = EINVAL;
put_fd(descriptor);
return retval;
}
int
user_ioctl(int fd, ulong op, void *buffer, size_t length)
{
struct file_descriptor *descriptor;
int status;
CHECK_USER_ADDR(buffer)
PRINT(("user_ioctl: fd %d\n", fd));
descriptor = get_fd(get_current_io_context(false), fd);
if (!descriptor)
return EBADF;
if (descriptor->ops->fd_ioctl)
status = descriptor->ops->fd_ioctl(descriptor, op, buffer, length);
else
status = EOPNOTSUPP;
return status;
}
ssize_t
user_read_dir(int fd, struct dirent *buffer,size_t bufferSize,uint32 maxCount)
{
struct file_descriptor *descriptor;
ssize_t retval;
CHECK_USER_ADDR(buffer)
PRINT(("user_read_dir(fd = %d, buffer = 0x%p, bufferSize = %ld, count = %d)\n",fd,buffer,bufferSize,maxCount));
descriptor = get_fd(get_current_io_context(false), fd);
if (descriptor == NULL)
return EBADF;
if (descriptor->ops->fd_read_dir) {
uint32 count = maxCount;
retval = descriptor->ops->fd_read_dir(descriptor,buffer,bufferSize,&count);
if (retval >= 0)
retval = count;
} else
retval = EOPNOTSUPP;
put_fd(descriptor);
return retval;
}
status_t
user_rewind_dir(int fd)
{
struct file_descriptor *descriptor;
status_t status;
PRINT(("user_rewind_dir(fd = %d)\n",fd));
descriptor = get_fd(get_current_io_context(false), fd);
if (descriptor == NULL)
return EBADF;
if (descriptor->ops->fd_rewind_dir)
status = descriptor->ops->fd_rewind_dir(descriptor);
else
status = EOPNOTSUPP;
put_fd(descriptor);
return status;
}
int
user_fstat(int fd, struct stat *stat)
{
struct file_descriptor *descriptor;
ssize_t retval;
/* This is a user_function, so abort if we have a kernel address */
CHECK_USER_ADDR(stat)
descriptor = get_fd(get_current_io_context(false), fd);
if (descriptor == NULL)
return EBADF;
if (descriptor->ops->fd_stat) {
// we're using the stat buffer on the stack to not have to
// lock the given stat buffer in memory
struct stat kstat;
retval = descriptor->ops->fd_stat(descriptor, &kstat);
if (retval >= 0)
retval = user_memcpy(stat, &kstat, sizeof(*stat));
} else
retval = EOPNOTSUPP;
put_fd(descriptor);
return retval;
}
int
user_close(int fd)
{
struct io_context *ioContext = get_current_io_context(false);
struct file_descriptor *descriptor = get_fd(ioContext, fd);
int retval;
if (descriptor == NULL)
return EBADF;
if (descriptor->ops->fd_close)
retval = descriptor->ops->fd_close(descriptor, fd, ioContext);
else
retval = EOPNOTSUPP;
put_fd(descriptor);
return retval;
}
// #pragma mark -
/*** SYSTEM functions ***/
ssize_t
sys_read(int fd, void *buffer, off_t pos, size_t length)
{
struct file_descriptor *descriptor;
ssize_t retval;
/* This is a sys_function, so abort if we have a kernel address */
// I've removed those checks because we have to be able to load things
// into user memory as well -- axeld.
//CHECK_SYS_ADDR(buffer)
descriptor = get_fd(get_current_io_context(true), fd);
if (!descriptor)
return EBADF;
if (descriptor->ops->fd_read) {
retval = descriptor->ops->fd_read(descriptor, buffer, pos, &length);
if (retval >= 0)
retval = (ssize_t)length;
} else
retval = EINVAL;
put_fd(descriptor);
return retval;
}
ssize_t
sys_write(int fd, const void *buffer, off_t pos, size_t length)
{
struct file_descriptor *descriptor;
ssize_t retval;
// dprintf("sys_write: fd %d\n", fd);
// CHECK_SYS_ADDR(buffer)
descriptor = get_fd(get_current_io_context(true), fd);
if (descriptor == NULL)
return EBADF;
if (descriptor->ops->fd_write) {
retval = descriptor->ops->fd_write(descriptor, buffer, pos, &length);
if (retval >= 0)
retval = (ssize_t)length;
PRINT(("sys_write(%d) = %ld (rlen = %ld)\n", fd, retval, length));
} else
retval = EINVAL;
put_fd(descriptor);
return retval;
}
int
sys_ioctl(int fd, ulong op, void *buffer, size_t length)
{
struct file_descriptor *descriptor;
int status;
PRINT(("sys_ioctl: fd %d\n", fd));
CHECK_SYS_ADDR(buffer)
descriptor = get_fd(get_current_io_context(true), fd);
if (descriptor == NULL)
return EBADF;
if (descriptor->ops->fd_ioctl)
status = descriptor->ops->fd_ioctl(descriptor, op, buffer, length);
else
status = EOPNOTSUPP;
put_fd(descriptor);
return status;
}
ssize_t
sys_read_dir(int fd, struct dirent *buffer,size_t bufferSize,uint32 maxCount)
{
struct file_descriptor *descriptor;
ssize_t retval;
PRINT(("sys_read_dir(fd = %d, buffer = 0x%p, bufferSize = %ld, count = %u)\n",fd,buffer,bufferSize,maxCount));
descriptor = get_fd(get_current_io_context(false), fd);
if (descriptor == NULL)
return EBADF;
if (descriptor->ops->fd_read_dir) {
uint32 count = maxCount;
retval = descriptor->ops->fd_read_dir(descriptor,buffer,bufferSize,&count);
if (retval >= 0)
retval = count;
} else
retval = EOPNOTSUPP;
put_fd(descriptor);
return retval;
}
status_t
sys_rewind_dir(int fd)
{
struct file_descriptor *descriptor;
status_t status;
PRINT(("user_rewind_dir(fd = %d)\n",fd));
descriptor = get_fd(get_current_io_context(false), fd);
if (descriptor == NULL)
return EBADF;
if (descriptor->ops->fd_rewind_dir)
status = descriptor->ops->fd_rewind_dir(descriptor);
else
status = EOPNOTSUPP;
put_fd(descriptor);
return status;
}
int
sys_close(int fd)
{
struct io_context *ioContext = get_current_io_context(true);
struct file_descriptor *descriptor = get_fd(ioContext, fd);
int status;
if (descriptor == NULL)
return EBADF;
if (descriptor->ops->fd_close)
status = descriptor->ops->fd_close(descriptor, fd, ioContext);
else
status = EOPNOTSUPP;
put_fd(descriptor);
return status;
}