tmk_core/tool/mbed/mbed-sdk/libraries/mbed/common/LocalFileSystem.cpp

   1 /* mbed Microcontroller Library
   2  * Copyright (c) 2006-2013 ARM Limited
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 #include "LocalFileSystem.h"
  17
  18 #if DEVICE_LOCALFILESYSTEM
  19
  20 #include "semihost_api.h"
  21 #include <string.h>
  22 #include <stdio.h>
  23
  24 namespace mbed {
  25
  26 /* Extension to FINFO type defined in RTL.h (in Keil RL) - adds 'create time'. */
  27 typedef struct {
  28     unsigned char  hr;   /* Hours    [0..23]                  */
  29     unsigned char  min;  /* Minutes  [0..59]                  */
  30     unsigned char  sec;  /* Seconds  [0..59]                  */
  31     unsigned char  day;  /* Day      [1..31]                  */
  32     unsigned char  mon;  /* Month    [1..12]                  */
  33     unsigned short year; /* Year     [1980..2107]             */
  34 } FTIME;
  35
  36 typedef struct {         /* File Search info record           */
  37     char  name[32];      /* File name                         */
  38     long  size;          /* File size in bytes                */
  39     int   fileID;        /* System File Identification        */
  40     FTIME create_time;   /* Date & time file was created      */
  41     FTIME write_time;    /* Date & time of last write         */
  42 } XFINFO;
  43
  44 #define RESERVED_FOR_USER_APPLICATIONS (0x100) /* 0x100 - 0x1ff */
  45 #define USR_XFFIND (RESERVED_FOR_USER_APPLICATIONS + 0)
  46
  47 static int xffind (const char *pattern, XFINFO *info) {
  48     unsigned param[4];
  49
  50     param[0] = (unsigned long)pattern;
  51     param[1] = (unsigned long)strlen(pattern);
  52     param[2] = (unsigned long)info;
  53     param[3] = (unsigned long)sizeof(XFINFO);
  54
  55     return __semihost(USR_XFFIND, param);
  56 }
  57
  58 #define OPEN_R          0
  59 #define OPEN_B          1
  60 #define OPEN_PLUS       2
  61 #define OPEN_W          4
  62 #define OPEN_A          8
  63 #define OPEN_INVALID   -1
  64
  65 int posix_to_semihost_open_flags(int flags) {
  66     /* POSIX flags -> semihosting open mode */
  67     int openmode;
  68     if (flags & O_RDWR) {
  69         /* a plus mode */
  70         openmode = OPEN_PLUS;
  71         if (flags & O_APPEND) {
  72             openmode |= OPEN_A;
  73         } else if (flags & O_TRUNC) {
  74             openmode |= OPEN_W;
  75         } else {
  76             openmode |= OPEN_R;
  77         }
  78     } else if (flags & O_WRONLY) {
  79         /* write or append */
  80         if (flags & O_APPEND) {
  81             openmode = OPEN_A;
  82         } else {
  83             openmode = OPEN_W;
  84         }
  85     } else if (flags == O_RDONLY) {
  86         /* read mode */
  87         openmode = OPEN_R;
  88     } else {
  89         /* invalid flags */
  90         openmode = OPEN_INVALID;
  91     }
  92
  93     return openmode;
  94 }
  95
  96 FILEHANDLE local_file_open(const char* name, int flags) {
  97     int openmode = posix_to_semihost_open_flags(flags);
  98     if (openmode == OPEN_INVALID) {
  99         return (FILEHANDLE)NULL;
 100     }
 101
 102     FILEHANDLE fh = semihost_open(name, openmode);
 103     if (fh == -1) {
 104         return (FILEHANDLE)NULL;
 105     }
 106
 107     return fh;
 108 }
 109
 110 LocalFileHandle::LocalFileHandle(FILEHANDLE fh) : _fh(fh), pos(0) {
 111 }
 112
 113 int LocalFileHandle::close() {
 114     int retval = semihost_close(_fh);
 115     delete this;
 116     return retval;
 117 }
 118
 119 ssize_t LocalFileHandle::write(const void *buffer, size_t length) {
 120     ssize_t n = semihost_write(_fh, (const unsigned char*)buffer, length, 0); // number of characters not written
 121     n = length - n; // number of characters written
 122     pos += n;
 123     return n;
 124 }
 125
 126 ssize_t LocalFileHandle::read(void *buffer, size_t length) {
 127     ssize_t n = semihost_read(_fh, (unsigned char*)buffer, length, 0); // number of characters not read
 128     n = length - n; // number of characters read
 129     pos += n;
 130     return n;
 131 }
 132
 133 int LocalFileHandle::isatty() {
 134     return semihost_istty(_fh);
 135 }
 136
 137 off_t LocalFileHandle::lseek(off_t position, int whence) {
 138     if (whence == SEEK_CUR) {
 139         position += pos;
 140     } else if (whence == SEEK_END) {
 141         position += semihost_flen(_fh);
 142     } /* otherwise SEEK_SET, so position is fine */
 143
 144     /* Always seems to return -1, so just ignore for now. */
 145     semihost_seek(_fh, position);
 146     pos = position;
 147     return position;
 148 }
 149
 150 int LocalFileHandle::fsync() {
 151     return semihost_ensure(_fh);
 152 }
 153
 154 off_t LocalFileHandle::flen() {
 155     return semihost_flen(_fh);
 156 }
 157
 158 class LocalDirHandle : public DirHandle {
 159
 160 public:
 161     struct dirent cur_entry;
 162     XFINFO info;
 163
 164     LocalDirHandle() : cur_entry(), info() {
 165     }
 166
 167     virtual int closedir() {
 168         delete this;
 169         return 0;
 170     }
 171
 172     virtual struct dirent *readdir() {
 173         if (xffind("*", &info)!=0) {
 174             return NULL;
 175         }
 176         memcpy(cur_entry.d_name, info.name, sizeof(info.name));
 177         return &cur_entry;
 178     }
 179
 180     virtual void rewinddir() {
 181         info.fileID = 0;
 182     }
 183
 184     virtual off_t telldir() {
 185         return info.fileID;
 186     }
 187
 188     virtual void seekdir(off_t offset) {
 189         info.fileID = offset;
 190     }
 191 };
 192
 193 FileHandle *LocalFileSystem::open(const char* name, int flags) {
 194     /* reject filenames with / in them */
 195     for (const char *tmp = name; *tmp; tmp++) {
 196         if (*tmp == '/') {
 197             return NULL;
 198         }
 199     }
 200
 201     int openmode = posix_to_semihost_open_flags(flags);
 202     if (openmode == OPEN_INVALID) {
 203         return NULL;
 204     }
 205
 206     FILEHANDLE fh = semihost_open(name, openmode);
 207     if (fh == -1) {
 208         return NULL;
 209     }
 210     return new LocalFileHandle(fh);
 211 }
 212
 213 int LocalFileSystem::remove(const char *filename) {
 214     return semihost_remove(filename);
 215 }
 216
 217 DirHandle *LocalFileSystem::opendir(const char *name) {
 218     return new LocalDirHandle();
 219 }
 220
 221 } // namespace mbed
 222
 223 #endif