Contiki 2.6
|
00001 /* 00002 * Copyright (c) 2004, Swedish Institute of Computer Science. 00003 * All rights reserved. 00004 * 00005 * Redistribution and use in source and binary forms, with or without 00006 * modification, are permitted provided that the following conditions 00007 * are met: 00008 * 1. Redistributions of source code must retain the above copyright 00009 * notice, this list of conditions and the following disclaimer. 00010 * 2. Redistributions in binary form must reproduce the above copyright 00011 * notice, this list of conditions and the following disclaimer in the 00012 * documentation and/or other materials provided with the distribution. 00013 * 3. Neither the name of the Institute nor the names of its contributors 00014 * may be used to endorse or promote products derived from this software 00015 * without specific prior written permission. 00016 * 00017 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 00018 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 00019 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 00020 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 00021 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 00022 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 00023 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 00024 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 00025 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 00026 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 00027 * SUCH DAMAGE. 00028 * 00029 * This file is part of the Contiki operating system. 00030 * 00031 * Author: Adam Dunkels <adam@sics.se> 00032 * 00033 * $Id: cfs-xmem.c,v 1.11 2009/02/27 14:25:38 nvt-se Exp $ 00034 */ 00035 00036 #include "cfs/cfs.h" 00037 #include "dev/xmem.h" 00038 00039 struct filestate { 00040 int flag; 00041 #define FLAG_FILE_CLOSED 0 00042 #define FLAG_FILE_OPEN 1 00043 unsigned int fileptr; 00044 unsigned int filesize; 00045 }; 00046 00047 #ifdef CFS_XMEM_CONF_OFFSET 00048 #define CFS_XMEM_OFFSET CFS_XMEM_CONF_OFFSET 00049 #else 00050 #define CFS_XMEM_OFFSET 0 00051 #endif 00052 00053 /* Note the CFS_XMEM_CONF_SIZE must be a tuple of XMEM_ERASE_UNIT_SIZE */ 00054 #ifdef CFS_XMEM_CONF_SIZE 00055 #define CFS_XMEM_SIZE CFS_XMEM_CONF_SIZE 00056 #else 00057 #define CFS_XMEM_SIZE XMEM_ERASE_UNIT_SIZE 00058 #endif 00059 00060 static struct filestate file; 00061 00062 /*---------------------------------------------------------------------------*/ 00063 int 00064 cfs_open(const char *n, int f) 00065 { 00066 if(file.flag == FLAG_FILE_CLOSED) { 00067 file.flag = FLAG_FILE_OPEN; 00068 if(f & CFS_READ) { 00069 file.fileptr = 0; 00070 } 00071 if(f & CFS_WRITE){ 00072 if(f & CFS_APPEND) { 00073 file.fileptr = file.filesize; 00074 } else { 00075 file.fileptr = 0; 00076 file.filesize = 0; 00077 xmem_erase(CFS_XMEM_SIZE, CFS_XMEM_OFFSET); 00078 } 00079 } 00080 return 1; 00081 } else { 00082 return -1; 00083 } 00084 } 00085 /*---------------------------------------------------------------------------*/ 00086 void 00087 cfs_close(int f) 00088 { 00089 file.flag = FLAG_FILE_CLOSED; 00090 } 00091 /*---------------------------------------------------------------------------*/ 00092 int 00093 cfs_read(int f, void *buf, unsigned int len) 00094 { 00095 if(file.fileptr + len > CFS_XMEM_SIZE) { 00096 len = CFS_XMEM_SIZE - file.fileptr; 00097 } 00098 00099 if(file.fileptr + len > file.filesize) { 00100 len = file.filesize - file.fileptr; 00101 } 00102 00103 if(f == 1) { 00104 xmem_pread(buf, len, CFS_XMEM_OFFSET + file.fileptr); 00105 file.fileptr += len; 00106 return len; 00107 } else { 00108 return -1; 00109 } 00110 } 00111 /*---------------------------------------------------------------------------*/ 00112 int 00113 cfs_write(int f, const void *buf, unsigned int len) 00114 { 00115 if(file.fileptr >= CFS_XMEM_SIZE) { 00116 return 0; 00117 } 00118 if(file.fileptr + len > CFS_XMEM_SIZE) { 00119 len = CFS_XMEM_SIZE - file.fileptr; 00120 } 00121 00122 if(file.fileptr + len > file.filesize) { 00123 /* Extend the size of the file. */ 00124 file.filesize = file.fileptr + len; 00125 } 00126 00127 if(f == 1) { 00128 xmem_pwrite(buf, len, CFS_XMEM_OFFSET + file.fileptr); 00129 file.fileptr += len; 00130 return len; 00131 } else { 00132 return -1; 00133 } 00134 } 00135 /*---------------------------------------------------------------------------*/ 00136 cfs_offset_t 00137 cfs_seek(int f, cfs_offset_t o, int w) 00138 { 00139 if(w == CFS_SEEK_SET && f == 1) { 00140 if(o > file.filesize) { 00141 o = file.filesize; 00142 } 00143 file.fileptr = o; 00144 return o; 00145 } 00146 return -1; 00147 } 00148 /*---------------------------------------------------------------------------*/ 00149 int 00150 cfs_remove(const char *name) 00151 { 00152 file.flag = FLAG_FILE_CLOSED; 00153 file.fileptr = 0; 00154 file.filesize = 0; 00155 xmem_erase(CFS_XMEM_SIZE, CFS_XMEM_OFFSET); 00156 return 0; 00157 } 00158 /*---------------------------------------------------------------------------*/ 00159 int 00160 cfs_opendir(struct cfs_dir *p, const char *n) 00161 { 00162 return -1; 00163 } 00164 /*---------------------------------------------------------------------------*/ 00165 int 00166 cfs_readdir(struct cfs_dir *p, struct cfs_dirent *e) 00167 { 00168 return -1; 00169 } 00170 /*---------------------------------------------------------------------------*/ 00171 void 00172 cfs_closedir(struct cfs_dir *p) 00173 { 00174 } 00175 /*---------------------------------------------------------------------------*/