siva surendar / mbed-dev

mbed library sources. Supersedes mbed-src.

Fork of mbed-dev by mbed official

drivers/LocalFileSystem.cpp@150:da61ba4e9755, 2016-11-25 (annotated)

Committer:
sivasuren
Date:
Fri Nov 25 07:57:40 2016 +0000
Revision:
150:da61ba4e9755
Parent:
149:156823d33999 
surendar changes

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 149:156823d33999 1 /* mbed Microcontroller Library
<> 149:156823d33999 2 * Copyright (c) 2006-2013 ARM Limited
<> 149:156823d33999 3 *
<> 149:156823d33999 4 * Licensed under the Apache License, Version 2.0 (the "License");
<> 149:156823d33999 5 * you may not use this file except in compliance with the License.
<> 149:156823d33999 6 * You may obtain a copy of the License at
<> 149:156823d33999 7 *
<> 149:156823d33999 8 * http://www.apache.org/licenses/LICENSE-2.0
<> 149:156823d33999 9 *
<> 149:156823d33999 10 * Unless required by applicable law or agreed to in writing, software
<> 149:156823d33999 11 * distributed under the License is distributed on an "AS IS" BASIS,
<> 149:156823d33999 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 149:156823d33999 13 * See the License for the specific language governing permissions and
<> 149:156823d33999 14 * limitations under the License.
<> 149:156823d33999 15 */
<> 149:156823d33999 16 #include "drivers/LocalFileSystem.h"
<> 149:156823d33999 17
<> 149:156823d33999 18 #if DEVICE_LOCALFILESYSTEM
<> 149:156823d33999 19
<> 149:156823d33999 20 #include "platform/semihost_api.h"
<> 149:156823d33999 21 #include <string.h>
<> 149:156823d33999 22 #include <stdio.h>
<> 149:156823d33999 23
<> 149:156823d33999 24 namespace mbed {
<> 149:156823d33999 25
<> 149:156823d33999 26 /* Extension to FINFO type defined in RTL.h (in Keil RL) - adds 'create time'. */
<> 149:156823d33999 27 typedef struct {
<> 149:156823d33999 28 unsigned char hr; /* Hours [0..23] */
<> 149:156823d33999 29 unsigned char min; /* Minutes [0..59] */
<> 149:156823d33999 30 unsigned char sec; /* Seconds [0..59] */
<> 149:156823d33999 31 unsigned char day; /* Day [1..31] */
<> 149:156823d33999 32 unsigned char mon; /* Month [1..12] */
<> 149:156823d33999 33 unsigned short year; /* Year [1980..2107] */
<> 149:156823d33999 34 } FTIME;
<> 149:156823d33999 35
<> 149:156823d33999 36 typedef struct { /* File Search info record */
<> 149:156823d33999 37 char name[32]; /* File name */
<> 149:156823d33999 38 long size; /* File size in bytes */
<> 149:156823d33999 39 int fileID; /* System File Identification */
<> 149:156823d33999 40 FTIME create_time; /* Date & time file was created */
<> 149:156823d33999 41 FTIME write_time; /* Date & time of last write */
<> 149:156823d33999 42 } XFINFO;
<> 149:156823d33999 43
<> 149:156823d33999 44 #define RESERVED_FOR_USER_APPLICATIONS (0x100) /* 0x100 - 0x1ff */
<> 149:156823d33999 45 #define USR_XFFIND (RESERVED_FOR_USER_APPLICATIONS + 0)
<> 149:156823d33999 46
<> 149:156823d33999 47 static int xffind (const char *pattern, XFINFO *info) {
<> 149:156823d33999 48 unsigned param[4];
<> 149:156823d33999 49
<> 149:156823d33999 50 param[0] = (unsigned long)pattern;
<> 149:156823d33999 51 param[1] = (unsigned long)strlen(pattern);
<> 149:156823d33999 52 param[2] = (unsigned long)info;
<> 149:156823d33999 53 param[3] = (unsigned long)sizeof(XFINFO);
<> 149:156823d33999 54
<> 149:156823d33999 55 return __semihost(USR_XFFIND, param);
<> 149:156823d33999 56 }
<> 149:156823d33999 57
<> 149:156823d33999 58 #define OPEN_R 0
<> 149:156823d33999 59 #define OPEN_B 1
<> 149:156823d33999 60 #define OPEN_PLUS 2
<> 149:156823d33999 61 #define OPEN_W 4
<> 149:156823d33999 62 #define OPEN_A 8
<> 149:156823d33999 63 #define OPEN_INVALID -1
<> 149:156823d33999 64
<> 149:156823d33999 65 int posix_to_semihost_open_flags(int flags) {
<> 149:156823d33999 66 /* POSIX flags -> semihosting open mode */
<> 149:156823d33999 67 int openmode;
<> 149:156823d33999 68 if (flags & O_RDWR) {
<> 149:156823d33999 69 /* a plus mode */
<> 149:156823d33999 70 openmode = OPEN_PLUS;
<> 149:156823d33999 71 if (flags & O_APPEND) {
<> 149:156823d33999 72 openmode |= OPEN_A;
<> 149:156823d33999 73 } else if (flags & O_TRUNC) {
<> 149:156823d33999 74 openmode |= OPEN_W;
<> 149:156823d33999 75 } else {
<> 149:156823d33999 76 openmode |= OPEN_R;
<> 149:156823d33999 77 }
<> 149:156823d33999 78 } else if (flags & O_WRONLY) {
<> 149:156823d33999 79 /* write or append */
<> 149:156823d33999 80 if (flags & O_APPEND) {
<> 149:156823d33999 81 openmode = OPEN_A;
<> 149:156823d33999 82 } else {
<> 149:156823d33999 83 openmode = OPEN_W;
<> 149:156823d33999 84 }
<> 149:156823d33999 85 } else if (flags == O_RDONLY) {
<> 149:156823d33999 86 /* read mode */
<> 149:156823d33999 87 openmode = OPEN_R;
<> 149:156823d33999 88 } else {
<> 149:156823d33999 89 /* invalid flags */
<> 149:156823d33999 90 openmode = OPEN_INVALID;
<> 149:156823d33999 91 }
<> 149:156823d33999 92
<> 149:156823d33999 93 return openmode;
<> 149:156823d33999 94 }
<> 149:156823d33999 95
<> 149:156823d33999 96 FILEHANDLE local_file_open(const char* name, int flags) {
<> 149:156823d33999 97 int openmode = posix_to_semihost_open_flags(flags);
<> 149:156823d33999 98 if (openmode == OPEN_INVALID) {
<> 149:156823d33999 99 return (FILEHANDLE)NULL;
<> 149:156823d33999 100 }
<> 149:156823d33999 101
<> 149:156823d33999 102 FILEHANDLE fh = semihost_open(name, openmode);
<> 149:156823d33999 103 if (fh == -1) {
<> 149:156823d33999 104 return (FILEHANDLE)NULL;
<> 149:156823d33999 105 }
<> 149:156823d33999 106
<> 149:156823d33999 107 return fh;
<> 149:156823d33999 108 }
<> 149:156823d33999 109
<> 149:156823d33999 110 LocalFileHandle::LocalFileHandle(FILEHANDLE fh) : _fh(fh), pos(0) {
<> 149:156823d33999 111 // No lock needed in constructor
<> 149:156823d33999 112 }
<> 149:156823d33999 113
<> 149:156823d33999 114 int LocalFileHandle::close() {
<> 149:156823d33999 115 int retval = semihost_close(_fh);
<> 149:156823d33999 116 delete this;
<> 149:156823d33999 117 return retval;
<> 149:156823d33999 118 }
<> 149:156823d33999 119
<> 149:156823d33999 120 ssize_t LocalFileHandle::write(const void *buffer, size_t length) {
<> 149:156823d33999 121 lock();
<> 149:156823d33999 122 ssize_t n = semihost_write(_fh, (const unsigned char*)buffer, length, 0); // number of characters not written
<> 149:156823d33999 123 n = length - n; // number of characters written
<> 149:156823d33999 124 pos += n;
<> 149:156823d33999 125 unlock();
<> 149:156823d33999 126 return n;
<> 149:156823d33999 127 }
<> 149:156823d33999 128
<> 149:156823d33999 129 ssize_t LocalFileHandle::read(void *buffer, size_t length) {
<> 149:156823d33999 130 lock();
<> 149:156823d33999 131 ssize_t n = semihost_read(_fh, (unsigned char*)buffer, length, 0); // number of characters not read
<> 149:156823d33999 132 n = length - n; // number of characters read
<> 149:156823d33999 133 pos += n;
<> 149:156823d33999 134 unlock();
<> 149:156823d33999 135 return n;
<> 149:156823d33999 136 }
<> 149:156823d33999 137
<> 149:156823d33999 138 int LocalFileHandle::isatty() {
<> 149:156823d33999 139 lock();
<> 149:156823d33999 140 int ret = semihost_istty(_fh);
<> 149:156823d33999 141 unlock();
<> 149:156823d33999 142 return ret;
<> 149:156823d33999 143 }
<> 149:156823d33999 144
<> 149:156823d33999 145 off_t LocalFileHandle::lseek(off_t position, int whence) {
<> 149:156823d33999 146 lock();
<> 149:156823d33999 147 if (whence == SEEK_CUR) {
<> 149:156823d33999 148 position += pos;
<> 149:156823d33999 149 } else if (whence == SEEK_END) {
<> 149:156823d33999 150 position += semihost_flen(_fh);
<> 149:156823d33999 151 } /* otherwise SEEK_SET, so position is fine */
<> 149:156823d33999 152
<> 149:156823d33999 153 /* Always seems to return -1, so just ignore for now. */
<> 149:156823d33999 154 semihost_seek(_fh, position);
<> 149:156823d33999 155 pos = position;
<> 149:156823d33999 156 unlock();
<> 149:156823d33999 157 return position;
<> 149:156823d33999 158 }
<> 149:156823d33999 159
<> 149:156823d33999 160 int LocalFileHandle::fsync() {
<> 149:156823d33999 161 lock();
<> 149:156823d33999 162 int ret = semihost_ensure(_fh);
<> 149:156823d33999 163 unlock();
<> 149:156823d33999 164 return ret;
<> 149:156823d33999 165 }
<> 149:156823d33999 166
<> 149:156823d33999 167 off_t LocalFileHandle::flen() {
<> 149:156823d33999 168 lock();
<> 149:156823d33999 169 off_t off = semihost_flen(_fh);
<> 149:156823d33999 170 unlock();
<> 149:156823d33999 171 return off;
<> 149:156823d33999 172 }
<> 149:156823d33999 173
<> 149:156823d33999 174 void LocalFileHandle::lock() {
<> 149:156823d33999 175 _mutex.lock();
<> 149:156823d33999 176 }
<> 149:156823d33999 177
<> 149:156823d33999 178 void LocalFileHandle::unlock() {
<> 149:156823d33999 179 _mutex.unlock();
<> 149:156823d33999 180 }
<> 149:156823d33999 181
<> 149:156823d33999 182 class LocalDirHandle : public DirHandle {
<> 149:156823d33999 183
<> 149:156823d33999 184 public:
<> 149:156823d33999 185 struct dirent cur_entry;
<> 149:156823d33999 186 XFINFO info;
<> 149:156823d33999 187
<> 149:156823d33999 188 LocalDirHandle() : cur_entry(), info() {
<> 149:156823d33999 189 }
<> 149:156823d33999 190
<> 149:156823d33999 191 virtual int closedir() {
<> 149:156823d33999 192 // No lock can be used in destructor
<> 149:156823d33999 193 delete this;
<> 149:156823d33999 194 return 0;
<> 149:156823d33999 195 }
<> 149:156823d33999 196
<> 149:156823d33999 197 virtual struct dirent *readdir() {
<> 149:156823d33999 198 lock();
<> 149:156823d33999 199 if (xffind("*", &info)!=0) {
<> 149:156823d33999 200 unlock();
<> 149:156823d33999 201 return NULL;
<> 149:156823d33999 202 }
<> 149:156823d33999 203 memcpy(cur_entry.d_name, info.name, sizeof(info.name));
<> 149:156823d33999 204 unlock();
<> 149:156823d33999 205 return &cur_entry;
<> 149:156823d33999 206 }
<> 149:156823d33999 207
<> 149:156823d33999 208 virtual void rewinddir() {
<> 149:156823d33999 209 lock();
<> 149:156823d33999 210 info.fileID = 0;
<> 149:156823d33999 211 unlock();
<> 149:156823d33999 212 }
<> 149:156823d33999 213
<> 149:156823d33999 214 virtual off_t telldir() {
<> 149:156823d33999 215 lock();
<> 149:156823d33999 216 int fileId = info.fileID;
<> 149:156823d33999 217 unlock();
<> 149:156823d33999 218 return fileId;
<> 149:156823d33999 219 }
<> 149:156823d33999 220
<> 149:156823d33999 221 virtual void seekdir(off_t offset) {
<> 149:156823d33999 222 lock();
<> 149:156823d33999 223 info.fileID = offset;
<> 149:156823d33999 224 unlock();
<> 149:156823d33999 225 }
<> 149:156823d33999 226
<> 149:156823d33999 227 protected:
<> 149:156823d33999 228 PlatformMutex _mutex;
<> 149:156823d33999 229
<> 149:156823d33999 230 virtual void lock() {
<> 149:156823d33999 231 _mutex.lock();
<> 149:156823d33999 232 }
<> 149:156823d33999 233
<> 149:156823d33999 234 virtual void unlock() {
<> 149:156823d33999 235 _mutex.unlock();
<> 149:156823d33999 236 }
<> 149:156823d33999 237 };
<> 149:156823d33999 238
<> 149:156823d33999 239 FileHandle *LocalFileSystem::open(const char* name, int flags) {
<> 149:156823d33999 240 // No global state modified so function is thread safe
<> 149:156823d33999 241
<> 149:156823d33999 242 /* reject filenames with / in them */
<> 149:156823d33999 243 for (const char *tmp = name; *tmp; tmp++) {
<> 149:156823d33999 244 if (*tmp == '/') {
<> 149:156823d33999 245 return NULL;
<> 149:156823d33999 246 }
<> 149:156823d33999 247 }
<> 149:156823d33999 248
<> 149:156823d33999 249 int openmode = posix_to_semihost_open_flags(flags);
<> 149:156823d33999 250 if (openmode == OPEN_INVALID) {
<> 149:156823d33999 251 return NULL;
<> 149:156823d33999 252 }
<> 149:156823d33999 253
<> 149:156823d33999 254 FILEHANDLE fh = semihost_open(name, openmode);
<> 149:156823d33999 255 if (fh == -1) {
<> 149:156823d33999 256 return NULL;
<> 149:156823d33999 257 }
<> 149:156823d33999 258 return new LocalFileHandle(fh);
<> 149:156823d33999 259 }
<> 149:156823d33999 260
<> 149:156823d33999 261 int LocalFileSystem::remove(const char *filename) {
<> 149:156823d33999 262 // No global state modified so function is thread safe
<> 149:156823d33999 263
<> 149:156823d33999 264 return semihost_remove(filename);
<> 149:156823d33999 265 }
<> 149:156823d33999 266
<> 149:156823d33999 267 DirHandle *LocalFileSystem::opendir(const char *name) {
<> 149:156823d33999 268 // No global state modified so function is thread safe
<> 149:156823d33999 269
<> 149:156823d33999 270 return new LocalDirHandle();
<> 149:156823d33999 271 }
<> 149:156823d33999 272
<> 149:156823d33999 273 } // namespace mbed
<> 149:156823d33999 274
<> 149:156823d33999 275 #endif