eduOS/fs/fs.c
2015-01-18 07:42:58 +01:00

246 lines
6.2 KiB
C

/*
* Copyright (c) 2010, Stefan Lankes, RWTH Aachen University
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <eduos/stdlib.h>
#include <eduos/stdio.h>
#include <eduos/string.h>
#include <eduos/fs.h>
#include <eduos/errno.h>
#include <eduos/spinlock.h>
vfs_node_t* fs_root = NULL; // The root of the filesystem.
ssize_t read_fs(fildes_t* file, uint8_t* buffer, size_t size)
{
vfs_node_t* node = file->node;
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(file, buffer, size);
spinlock_unlock(&node->lock);
return ret;
}
ssize_t write_fs(fildes_t* file, uint8_t* buffer, size_t size)
{
vfs_node_t* node = file->node;
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(file, buffer, size);
spinlock_unlock(&node->lock);
return ret;
}
int open_fs(fildes_t* file, const char* name)
{
uint32_t ret = 0, i, j = 1;
vfs_node_t* file_node = NULL; /* file node */
vfs_node_t* dir_node = NULL;
char fname[MAX_FNAME];
if (BUILTIN_EXPECT(!name, 0))
return ret;
if (name[0] == '/')
file_node = fs_root;
while((name[j] != '\0') || ((file_node != NULL) && (file_node->type == FS_DIRECTORY))) {
i = 0;
while((name[j] != '/') && (name[j] != '\0')) {
fname[i] = name[j];
i++; j++;
}
fname[i] = '\0';
dir_node = file_node; /* file must be a directory */
file_node = finddir_fs(dir_node, fname);
if (name[j] == '/')
j++;
}
//kprintf("dir_node = %p, file_node = %p, name = %s \n", dir_node, file_node, fname);
/* file exists */
if(file_node) {
spinlock_lock(&file_node->lock);
file->node = file_node;
// Has the file_node got an open callback?
if (file_node->open != 0)
ret = file->node->open(file, NULL);
spinlock_unlock(&file_node->lock);
} else if (dir_node) { /* file doesn't exist or opendir was called */
spinlock_lock(&dir_node->lock);
file->node = dir_node;
// Has the dir_node got an open callback?
if (dir_node->open != 0)
ret = dir_node->open(file, fname);
spinlock_unlock(&dir_node->lock);
} else {
ret = -ENOENT;
}
return ret;
}
int close_fs(fildes_t* file)
{
int ret = -EINVAL;
if (BUILTIN_EXPECT(!(file->node), 0))
return ret;
spinlock_lock(&file->node->lock);
// Has the node got a close callback?
if (file->node->close != 0)
ret = file->node->close(file);
spinlock_unlock(&file->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;
}
void list_fs(vfs_node_t* node, uint32_t depth)
{
int j, i = 0;
dirent_t* dirent = NULL;
fildes_t* file = kmalloc(sizeof(fildes_t));
file->offset = 0;
file->flags = 0;
while ((dirent = readdir_fs(node, i)) != 0) {
for(j=0; j<depth; j++)
kputs(" ");
kprintf("%s\n", dirent->name);
if (strcmp(dirent->name, ".") && strcmp(dirent->name, "..")) {
vfs_node_t *new_node = finddir_fs(node, dirent->name);
if (new_node) {
if (new_node->type == FS_FILE) {
char buff[16] = {[0 ... 15] = 0x00};
file->node = new_node;
file->offset = 0;
file->flags = 0;
read_fs(file, (uint8_t*)buff, 8);
for(j=0; j<depth+1; j++)
kputs(" ");
kprintf("content: %s\n", buff);
} else list_fs(new_node, depth+1);
}
}
i++;
}
kfree(file);
}