static int
dup2_fd(int oldfd, int newfd, bool kernel)
{
struct file_descriptor *evicted = NULL;
struct io_context *context;
TRACE(("dup2_fd: ofd = %d, nfd = %d\n", oldfd, newfd));
// quick check
if (oldfd < 0 || newfd < 0)
return FSSH_B_FILE_ERROR;
// Get current I/O context and lock it
context = get_current_io_context(kernel);
fssh_mutex_lock(&context->io_mutex);
// Check if the fds are valid (mutex must be locked because
// the table size could be changed)
if ((uint32_t)oldfd >= context->table_size
|| (uint32_t)newfd >= context->table_size
|| context->fds[oldfd] == NULL) {
fssh_mutex_unlock(&context->io_mutex);
return FSSH_B_FILE_ERROR;
}
// Check for identity, note that it cannot be made above
// because we always want to return an error on invalid
// handles
if (oldfd != newfd) {
// Now do the work
evicted = context->fds[newfd];
fssh_atomic_add(&context->fds[oldfd]->ref_count, 1);
fssh_atomic_add(&context->fds[oldfd]->open_count, 1);
context->fds[newfd] = context->fds[oldfd];
if (evicted == NULL)
context->num_used_fds++;
}
fd_set_close_on_exec(context, newfd, false);
fssh_mutex_unlock(&context->io_mutex);
// Say bye bye to the evicted fd
if (evicted) {
close_fd(evicted);
put_fd(evicted);
}
return newfd;
}
int
new_fd_etc(struct io_context *context, struct file_descriptor *descriptor,
int firstIndex)
{
int fd = -1;
uint32_t i;
fssh_mutex_lock(&context->io_mutex);
for (i = firstIndex; i < context->table_size; i++) {
if (!context->fds[i]) {
fd = i;
break;
}
}
if (fd < 0) {
fd = FSSH_B_NO_MORE_FDS;
goto err;
}
context->fds[fd] = descriptor;
context->num_used_fds++;
fssh_atomic_add(&descriptor->open_count, 1);
err:
fssh_mutex_unlock(&context->io_mutex);
return fd;
}
static int
dup_fd(int fd, bool kernel)
{
struct io_context *context = get_current_io_context(kernel);
struct file_descriptor *descriptor;
int status;
TRACE(("dup_fd: fd = %d\n", fd));
// Try to get the fd structure
descriptor = get_fd(context, fd);
if (descriptor == NULL)
return FSSH_B_FILE_ERROR;
// now put the fd in place
status = new_fd(context, descriptor);
if (status < 0)
put_fd(descriptor);
else {
fssh_mutex_lock(&context->io_mutex);
fd_set_close_on_exec(context, status, false);
fssh_mutex_unlock(&context->io_mutex);
}
return status;
}
static struct file_descriptor *
remove_fd(struct io_context *context, int fd)
{
struct file_descriptor *descriptor = NULL;
if (fd < 0)
return NULL;
fssh_mutex_lock(&context->io_mutex);
if ((uint32_t)fd < context->table_size)
descriptor = context->fds[fd];
if (descriptor) {
// fd is valid
context->fds[fd] = NULL;
fd_set_close_on_exec(context, fd, false);
context->num_used_fds--;
if (descriptor->open_mode & FSSH_O_DISCONNECTED)
descriptor = NULL;
}
fssh_mutex_unlock(&context->io_mutex);
return descriptor;
}
struct file_descriptor *
get_fd(struct io_context *context, int fd)
{
struct file_descriptor *descriptor = NULL;
if (fd < 0)
return NULL;
fssh_mutex_lock(&context->io_mutex);
if ((uint32_t)fd < context->table_size)
descriptor = context->fds[fd];
if (descriptor != NULL) {
// Disconnected descriptors cannot be accessed anymore
if (descriptor->open_mode & FSSH_O_DISCONNECTED)
descriptor = NULL;
else
inc_fd_ref_count(descriptor);
}
fssh_mutex_unlock(&context->io_mutex);
return descriptor;
}
static fssh_status_t
read_from_file(file_cache_ref *ref, void *cookie, fssh_off_t offset,
int32_t pageOffset, fssh_addr_t buffer, fssh_size_t bufferSize)
{
fssh_iovec vec;
vec.iov_base = (void *)buffer;
vec.iov_len = bufferSize;
fssh_mutex_unlock(&ref->lock);
fssh_status_t status = vfs_read_pages(ref->node, cookie,
offset + pageOffset, &vec, 1, &bufferSize);
fssh_mutex_lock(&ref->lock);
return status;
}
