| 0,0 → 1,142 |
|---|
| /* |
| * Copyright (c) 2007 Jakub Jermar |
| * 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. |
| * - The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. |
| */ |
| |
| /** @addtogroup fs |
| * @{ |
| */ |
| |
| /** |
| * @file fat_ops.c |
| * @brief Implementation of VFS operations for the FAT file system server. |
| */ |
| |
| #include "fat.h" |
| #include "../../vfs/vfs.h" |
| #include <ipc/ipc.h> |
| #include <async.h> |
| #include <errno.h> |
| |
| #define PLB_GET_CHAR(i) (fat_reg.plb_ro[(i) % PLB_SIZE]) |
| |
| #define FAT_NAME_LEN 8 |
| #define FAT_EXT_LEN 3 |
| |
| #define FAT_PAD ' ' |
| |
| #define FAT_DENTRY_UNUSED 0x00 |
| #define FAT_DENTRY_E5_ESC 0x05 |
| #define FAT_DENTRY_DOT 0x2e |
| #define FAT_DENTRY_ERASED 0xe5 |
| |
| /** Compare one component of path to a directory entry. |
| * |
| * @param dentry Directory entry to compare the path component with. |
| * @param start Index into PLB where the path component starts. |
| * @param last Index of the last character of the path in PLB. |
| * |
| * @return Zero on failure or delta such that (index + delta) % |
| * PLB_SIZE points to a new path component in PLB. |
| */ |
| static unsigned match_path_component(fat_dentry_t *dentry, unsigned start, |
| unsigned last) |
| { |
| unsigned cur; /* current position in PLB */ |
| int pos; /* current position in dentry->name or dentry->ext */ |
| bool name_processed = false; |
| bool dot_processed = false; |
| bool ext_processed = false; |
| |
| if (last < start) |
| last += PLB_SIZE; |
| for (pos = 0, cur = start; (cur <= last) && (PLB_GET_CHAR(cur) != '/'); |
| pos++, cur++) { |
| if (!name_processed) { |
| if ((pos == FAT_NAME_LEN - 1) || |
| (dentry->name[pos + 1] == FAT_PAD)) { |
| /* this is the last character in name */ |
| name_processed = true; |
| } |
| if (dentry->name[0] == FAT_PAD) { |
| /* name is empty */ |
| name_processed = true; |
| } else if ((pos == 0) && (dentry->name[pos] == |
| FAT_DENTRY_E5_ESC)) { |
| if (PLB_GET_CHAR(cur) == 0xe5) |
| continue; |
| else |
| return 0; /* character mismatch */ |
| } else { |
| if (PLB_GET_CHAR(cur) == dentry->name[pos]) |
| continue; |
| else |
| return 0; /* character mismatch */ |
| } |
| } |
| if (!dot_processed) { |
| dot_processed = true; |
| pos = -1; |
| if (PLB_GET_CHAR(cur) != '.') |
| return 0; |
| continue; |
| } |
| if (!ext_processed) { |
| if ((pos == FAT_EXT_LEN - 1) || |
| (dentry->ext[pos + 1] == FAT_PAD)) { |
| /* this is the last character in ext */ |
| ext_processed = true; |
| } |
| if (dentry->ext[0] == FAT_PAD) { |
| /* ext is empty; the match will fail */ |
| ext_processed = true; |
| } else if (PLB_GET_CHAR(cur) == dentry->ext[pos]) { |
| continue; |
| } else { |
| /* character mismatch */ |
| return 0; |
| } |
| } |
| return 0; /* extra characters in the component */ |
| } |
| if (ext_processed || (name_processed && dentry->ext[0] == FAT_PAD)) |
| return cur - start; |
| else |
| return 0; |
| } |
| |
| void fat_lookup(ipc_callid_t rid, ipc_call_t *request) |
| { |
| int first = IPC_GET_ARG1(*request); |
| int second = IPC_GET_ARG2(*request); |
| int dev_handle = IPC_GET_ARG3(*request); |
| |
| |
| } |
| |
| /** |
| * @} |
| */ |