metalsvm/fs/fs.c
2011-04-12 16:48:16 +02:00

165 lines
3.5 KiB
C

/*
* Copyright 2010 Stefan Lankes, Chair for Operating Systems,
* RWTH Aachen University
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of MetalSVM.
*/
#include <metalsvm/stdio.h>
#include <metalsvm/string.h>
#include <metalsvm/fs.h>
#include <metalsvm/errno.h>
#include <metalsvm/spinlock.h>
vfs_node_t* fs_root = NULL; // The root of the filesystem.
ssize_t read_fs(vfs_node_t* node, uint8_t* buffer, size_t size, off_t offset)
{
ssize_t ret = -EINVAL;
if (BUILTIN_EXPECT(!node || !buffer, 0))
return ret;
spinlock_lock(&node->lock);
// Has the node got a read callback?
if (node->read != 0)
ret = node->read(node, buffer, size, offset);
spinlock_unlock(&node->lock);
return ret;
}
ssize_t write_fs(vfs_node_t* node, uint8_t* buffer, size_t size, off_t offset)
{
ssize_t ret = -EINVAL;
if (BUILTIN_EXPECT(!node || !buffer, 0))
return ret;
spinlock_lock(&node->lock);
// Has the node got a write callback?
if (node->write != 0)
ret = node->write(node, buffer, size, offset);
spinlock_unlock(&node->lock);
return ret;
}
int open_fs(vfs_node_t* node, uint8_t read, uint8_t write)
{
int ret = -EINVAL;
if (BUILTIN_EXPECT(!node, 0))
return ret;
spinlock_lock(&node->lock);
// Has the node got an open callback?
if (node->open != 0)
ret = node->open(node);
spinlock_unlock(&node->lock);
return ret;
}
int close_fs(vfs_node_t* node)
{
int ret = -EINVAL;
if (BUILTIN_EXPECT(!node, 0))
return ret;
spinlock_lock(&node->lock);
// Has the node got a close callback?
if (node->close != 0)
ret = node->close(node);
spinlock_unlock(&node->lock);
return ret;
}
struct dirent* readdir_fs(vfs_node_t * node, uint32_t index)
{
struct dirent* ret = NULL;
if (BUILTIN_EXPECT(!node, 0))
return ret;
spinlock_lock(&node->lock);
// Is the node a directory, and does it have a callback?
if ((node->type == FS_DIRECTORY) && node->readdir != 0)
ret = node->readdir(node, index);
spinlock_unlock(&node->lock);
return ret;
}
vfs_node_t* finddir_fs(vfs_node_t* node, const char *name)
{
vfs_node_t* ret = NULL;
if (BUILTIN_EXPECT(!node, 0))
return ret;
spinlock_lock(&node->lock);
// Is the node a directory, and does it have a callback?
if ((node->type == FS_DIRECTORY) && node->finddir != 0)
ret = node->finddir(node, name);
spinlock_unlock(&node->lock);
return ret;
}
vfs_node_t* mkdir_fs(vfs_node_t* node, const char *name)
{
vfs_node_t* ret = NULL;
if (BUILTIN_EXPECT(!node, 0))
return ret;
spinlock_lock(&node->lock);
if (node->mkdir != 0)
ret = node->mkdir(node, name);
spinlock_unlock(&node->lock);
return ret;
}
vfs_node_t* findnode_fs(const char* name)
{
uint32_t i, j = 1;
vfs_node_t* ret = NULL;
char fname[MAX_FNAME];
if (BUILTIN_EXPECT(!name, 0))
return ret;
if (name[0] == '/')
ret = fs_root;
while((name[j] != '\0') && ret) {
i = 0;
while((name[j] != '/') && (name[j] != '\0')) {
fname[i] = name[j];
i++; j++;
}
fname[i] = '\0';
ret = finddir_fs(ret, fname);
if (name[j] == '/')
j++;
}
return ret;
}