src/helper/fileio.c

   1 /***************************************************************************
   2  *   Copyright (C) 2007 by Dominic Rath                                    *
   3  *   Dominic.Rath@gmx.de                                                   *
   4  *                                                                         *
   5  *   Copyright (C) 2007,2008 Øyvind Harboe                                 *
   6  *   oyvind.harboe@zylin.com                                               *
   7  *                                                                         *
   8  *   Copyright (C) 2008 by Spencer Oliver                                  *
   9  *   spen@spen-soft.co.uk                                                  *
  10  *                                                                         *
  11  *   This program is free software; you can redistribute it and/or modify  *
  12  *   it under the terms of the GNU General Public License as published by  *
  13  *   the Free Software Foundation; either version 2 of the License, or     *
  14  *   (at your option) any later version.                                   *
  15  *                                                                         *
  16  *   This program is distributed in the hope that it will be useful,       *
  17  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  18  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  19  *   GNU General Public License for more details.                          *
  20  *                                                                         *
  21  *   You should have received a copy of the GNU General Public License     *
  22  *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
  23  ***************************************************************************/
  24
  25 #ifdef HAVE_CONFIG_H
  26 #include "config.h"
  27 #endif
  28
  29 #include "log.h"
  30 #include "configuration.h"
  31 #include "fileio.h"
  32
  33 struct fileio {
  34         char *url;
  35         size_t size;
  36         enum fileio_type type;
  37         enum fileio_access access;
  38         FILE *file;
  39 };
  40
  41 static inline int fileio_close_local(struct fileio *fileio)
  42 {
  43         int retval = fclose(fileio->file);
  44         if (retval != 0) {
  45                 if (retval == EBADF)
  46                         LOG_ERROR("BUG: fileio->file not a valid file descriptor");
  47                 else
  48                         LOG_ERROR("couldn't close %s: %s", fileio->url, strerror(errno));
  49
  50                 return ERROR_FILEIO_OPERATION_FAILED;
  51         }
  52
  53         return ERROR_OK;
  54 }
  55
  56 static inline int fileio_open_local(struct fileio *fileio)
  57 {
  58         char file_access[4];
  59         ssize_t file_size;
  60
  61         switch (fileio->access) {
  62                 case FILEIO_READ:
  63                         strcpy(file_access, "r");
  64                         break;
  65                 case FILEIO_WRITE:
  66                         strcpy(file_access, "w");
  67                         break;
  68                 case FILEIO_READWRITE:
  69                         strcpy(file_access, "w+");
  70                         break;
  71                 case FILEIO_APPEND:
  72                         strcpy(file_access, "a");
  73                         break;
  74                 case FILEIO_APPENDREAD:
  75                         strcpy(file_access, "a+");
  76                         break;
  77                 default:
  78                         LOG_ERROR("BUG: access neither read, write nor readwrite");
  79                         return ERROR_COMMAND_SYNTAX_ERROR;
  80         }
  81
  82         /* win32 always opens in binary mode */
  83 #ifndef _WIN32
  84         if (fileio->type == FILEIO_BINARY)
  85 #endif
  86                 strcat(file_access, "b");
  87
  88         fileio->file = open_file_from_path(fileio->url, file_access);
  89         if (!fileio->file) {
  90                 LOG_ERROR("couldn't open %s", fileio->url);
  91                 return ERROR_FILEIO_OPERATION_FAILED;
  92         }
  93
  94         file_size = 0;
  95
  96         if ((fileio->access != FILEIO_WRITE) || (fileio->access == FILEIO_READWRITE)) {
  97                 /* NB! Here we use fseek() instead of stat(), since stat is a
  98                  * more advanced operation that might not apply to e.g. a disk path
  99                  * that refers to e.g. a tftp client */
 100                 int result, result2;
 101
 102                 result = fseek(fileio->file, 0, SEEK_END);
 103
 104                 file_size = ftell(fileio->file);
 105
 106                 result2 = fseek(fileio->file, 0, SEEK_SET);
 107
 108                 if ((file_size < 0) || (result < 0) || (result2 < 0)) {
 109                         fileio_close_local(fileio);
 110                         return ERROR_FILEIO_OPERATION_FAILED;
 111                 }
 112         }
 113
 114         fileio->size = file_size;
 115
 116         return ERROR_OK;
 117 }
 118
 119 int fileio_open(struct fileio **fileio, const char *url,
 120                 enum fileio_access access_type, enum fileio_type type)
 121 {
 122         int retval;
 123         struct fileio *tmp;
 124
 125         tmp = malloc(sizeof(struct fileio));
 126
 127         tmp->type = type;
 128         tmp->access = access_type;
 129         tmp->url = strdup(url);
 130
 131         retval = fileio_open_local(tmp);
 132
 133         if (retval != ERROR_OK) {
 134                 free(tmp->url);
 135                 free(tmp);
 136                 return retval;
 137         }
 138
 139         *fileio = tmp;
 140
 141         return ERROR_OK;
 142 }
 143
 144 int fileio_close(struct fileio *fileio)
 145 {
 146         int retval;
 147
 148         retval = fileio_close_local(fileio);
 149
 150         free(fileio->url);
 151         free(fileio);
 152
 153         return retval;
 154 }
 155
 156 int fileio_seek(struct fileio *fileio, size_t position)
 157 {
 158         int retval;
 159
 160         retval = fseek(fileio->file, position, SEEK_SET);
 161
 162         if (retval != 0) {
 163                 LOG_ERROR("couldn't seek file %s: %s", fileio->url, strerror(errno));
 164                 return ERROR_FILEIO_OPERATION_FAILED;
 165         }
 166
 167         return ERROR_OK;
 168 }
 169
 170 static int fileio_local_read(struct fileio *fileio, size_t size, void *buffer,
 171                 size_t *size_read)
 172 {
 173         ssize_t retval;
 174
 175         retval = fread(buffer, 1, size, fileio->file);
 176         *size_read = (retval >= 0) ? retval : 0;
 177
 178         return (retval < 0) ? retval : ERROR_OK;
 179 }
 180
 181 int fileio_read(struct fileio *fileio, size_t size, void *buffer,
 182                 size_t *size_read)
 183 {
 184         return fileio_local_read(fileio, size, buffer, size_read);
 185 }
 186
 187 int fileio_read_u32(struct fileio *fileio, uint32_t *data)
 188 {
 189         int retval;
 190         uint8_t buf[4];
 191         size_t size_read;
 192
 193         retval = fileio_local_read(fileio, sizeof(uint32_t), buf, &size_read);
 194
 195         if (ERROR_OK == retval && sizeof(uint32_t) != size_read)
 196                 retval = -EIO;
 197         if (ERROR_OK == retval)
 198                 *data = be_to_h_u32(buf);
 199
 200         return retval;
 201 }
 202
 203 static int fileio_local_fgets(struct fileio *fileio, size_t size, void *buffer)
 204 {
 205         if (fgets(buffer, size, fileio->file) == NULL)
 206                 return ERROR_FILEIO_OPERATION_FAILED;
 207
 208         return ERROR_OK;
 209 }
 210
 211 int fileio_fgets(struct fileio *fileio, size_t size, void *buffer)
 212 {
 213         return fileio_local_fgets(fileio, size, buffer);
 214 }
 215
 216 static int fileio_local_write(struct fileio *fileio, size_t size,
 217                 const void *buffer, size_t *size_written)
 218 {
 219         ssize_t retval;
 220
 221         retval = fwrite(buffer, 1, size, fileio->file);
 222         *size_written = (retval >= 0) ? retval : 0;
 223
 224         return (retval < 0) ? retval : ERROR_OK;
 225 }
 226
 227 int fileio_write(struct fileio *fileio, size_t size, const void *buffer,
 228                 size_t *size_written)
 229 {
 230         int retval;
 231
 232         retval = fileio_local_write(fileio, size, buffer, size_written);
 233
 234         if (retval == ERROR_OK)
 235                 fileio->size += *size_written;
 236
 237         return retval;
 238 }
 239
 240 int fileio_write_u32(struct fileio *fileio, uint32_t data)
 241 {
 242         int retval;
 243         uint8_t buf[4];
 244         h_u32_to_be(buf, data);
 245         size_t size_written;
 246
 247         retval = fileio_write(fileio, 4, buf, &size_written);
 248
 249         if (ERROR_OK == retval && size_written != sizeof(uint32_t))
 250                 retval = -EIO;
 251
 252         return retval;
 253 }
 254
 255 /**
 256  * FIX!!!!
 257  *
 258  * For now this can not fail, but that's because a seek was executed
 259  * on startup.
 260  *
 261  * Avoiding the seek on startup opens up for using streams.
 262  *
 263  */
 264 int fileio_size(struct fileio *fileio, size_t *size)
 265 {
 266         *size = fileio->size;
 267
 268         return ERROR_OK;
 269 }