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| Rev | Author | Line No. | Line |
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| 2627 | jermar | 1 | /* |
| 2 | * Copyright (c) 2007 Jakub Jermar |
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| 3 | * All rights reserved. |
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| 4 | * |
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| 5 | * Redistribution and use in source and binary forms, with or without |
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| 6 | * modification, are permitted provided that the following conditions |
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| 7 | * are met: |
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| 8 | * |
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| 9 | * - Redistributions of source code must retain the above copyright |
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| 10 | * notice, this list of conditions and the following disclaimer. |
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| 11 | * - Redistributions in binary form must reproduce the above copyright |
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| 12 | * notice, this list of conditions and the following disclaimer in the |
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| 13 | * documentation and/or other materials provided with the distribution. |
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| 14 | * - The name of the author may not be used to endorse or promote products |
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| 15 | * derived from this software without specific prior written permission. |
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| 16 | * |
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| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
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| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
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| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
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| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
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| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
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| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
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| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
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| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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| 27 | */ |
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| 28 | |||
| 29 | /** @addtogroup fs |
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| 30 | * @{ |
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| 31 | */ |
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| 32 | |||
| 33 | /** |
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| 34 | * @file fat_ops.c |
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| 35 | * @brief Implementation of VFS operations for the FAT file system server. |
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| 36 | */ |
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| 37 | |||
| 38 | #include "fat.h" |
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| 2638 | jermar | 39 | #include "../../vfs/vfs.h" |
| 2627 | jermar | 40 | #include <ipc/ipc.h> |
| 41 | #include <async.h> |
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| 42 | #include <errno.h> |
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| 43 | |||
| 2643 | jermar | 44 | #define PLB_GET_CHAR(i) (fat_reg.plb_ro[(i) % PLB_SIZE]) |
| 2638 | jermar | 45 | |
| 46 | #define FAT_NAME_LEN 8 |
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| 47 | #define FAT_EXT_LEN 3 |
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| 48 | |||
| 49 | #define FAT_PAD ' ' |
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| 50 | |||
| 51 | #define FAT_DENTRY_UNUSED 0x00 |
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| 52 | #define FAT_DENTRY_E5_ESC 0x05 |
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| 53 | #define FAT_DENTRY_DOT 0x2e |
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| 54 | #define FAT_DENTRY_ERASED 0xe5 |
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| 55 | |||
| 2639 | jermar | 56 | /** Compare one component of path to a directory entry. |
| 57 | * |
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| 58 | * @param dentry Directory entry to compare the path component with. |
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| 59 | * @param start Index into PLB where the path component starts. |
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| 60 | * @param last Index of the last character of the path in PLB. |
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| 61 | * |
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| 62 | * @return Zero on failure or delta such that (index + delta) % |
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| 63 | * PLB_SIZE points to a new path component in PLB. |
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| 64 | */ |
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| 65 | static unsigned match_path_component(fat_dentry_t *dentry, unsigned start, |
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| 66 | unsigned last) |
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| 2638 | jermar | 67 | { |
| 2639 | jermar | 68 | unsigned cur; /* current position in PLB */ |
| 69 | int pos; /* current position in dentry->name or dentry->ext */ |
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| 70 | bool name_processed = false; |
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| 71 | bool dot_processed = false; |
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| 72 | bool ext_processed = false; |
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| 73 | |||
| 74 | if (last < start) |
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| 75 | last += PLB_SIZE; |
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| 76 | for (pos = 0, cur = start; (cur <= last) && (PLB_GET_CHAR(cur) != '/'); |
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| 77 | pos++, cur++) { |
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| 78 | if (!name_processed) { |
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| 79 | if ((pos == FAT_NAME_LEN - 1) || |
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| 80 | (dentry->name[pos + 1] == FAT_PAD)) { |
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| 81 | /* this is the last character in name */ |
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| 82 | name_processed = true; |
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| 83 | } |
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| 84 | if (dentry->name[0] == FAT_PAD) { |
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| 85 | /* name is empty */ |
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| 86 | name_processed = true; |
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| 87 | } else if ((pos == 0) && (dentry->name[pos] == |
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| 88 | FAT_DENTRY_E5_ESC)) { |
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| 89 | if (PLB_GET_CHAR(cur) == 0xe5) |
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| 90 | continue; |
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| 91 | else |
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| 92 | return 0; /* character mismatch */ |
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| 93 | } else { |
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| 94 | if (PLB_GET_CHAR(cur) == dentry->name[pos]) |
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| 95 | continue; |
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| 96 | else |
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| 97 | return 0; /* character mismatch */ |
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| 98 | } |
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| 99 | } |
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| 100 | if (!dot_processed) { |
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| 101 | dot_processed = true; |
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| 102 | pos = -1; |
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| 103 | if (PLB_GET_CHAR(cur) != '.') |
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| 104 | return 0; |
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| 105 | continue; |
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| 106 | } |
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| 107 | if (!ext_processed) { |
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| 108 | if ((pos == FAT_EXT_LEN - 1) || |
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| 109 | (dentry->ext[pos + 1] == FAT_PAD)) { |
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| 110 | /* this is the last character in ext */ |
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| 111 | ext_processed = true; |
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| 112 | } |
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| 113 | if (dentry->ext[0] == FAT_PAD) { |
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| 114 | /* ext is empty; the match will fail */ |
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| 115 | ext_processed = true; |
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| 116 | } else if (PLB_GET_CHAR(cur) == dentry->ext[pos]) { |
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| 117 | continue; |
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| 118 | } else { |
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| 119 | /* character mismatch */ |
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| 120 | return 0; |
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| 121 | } |
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| 122 | } |
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| 123 | return 0; /* extra characters in the component */ |
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| 124 | } |
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| 125 | if (ext_processed || (name_processed && dentry->ext[0] == FAT_PAD)) |
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| 126 | return cur - start; |
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| 127 | else |
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| 128 | return 0; |
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| 2638 | jermar | 129 | } |
| 130 | |||
| 2627 | jermar | 131 | void fat_lookup(ipc_callid_t rid, ipc_call_t *request) |
| 132 | { |
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| 133 | int first = IPC_GET_ARG1(*request); |
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| 134 | int second = IPC_GET_ARG2(*request); |
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| 135 | int dev_handle = IPC_GET_ARG3(*request); |
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| 136 | |||
| 137 | |||
| 138 | } |
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| 139 | |||
| 140 | /** |
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| 141 | * @} |
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| 142 | */ |