libdvdread4/dvd_input.c

   1 /*
   2  * Copyright (C) 2002 Samuel Hocevar <sam@zoy.org>,
   3  *                    Håkan Hjort <d95hjort@dtek.chalmers.se>
   4  *
   5  * This file is part of libdvdread.
   6  *
   7  * libdvdread is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * libdvdread is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with libdvdread; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  */
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <fcntl.h>
  25 #include <unistd.h>
  26
  27 #include "config.h"
  28 #include "dvdread/dvd_reader.h"
  29 #include "dvd_input.h"
  30
  31
  32 /* The function pointers that is the exported interface of this file. */
  33 dvd_input_t (*dvdinput_open)  (const char *);
  34 int         (*dvdinput_close) (dvd_input_t);
  35 int         (*dvdinput_seek)  (dvd_input_t, int);
  36 int         (*dvdinput_title) (dvd_input_t, int);
  37 int         (*dvdinput_read)  (dvd_input_t, void *, int, int);
  38 char *      (*dvdinput_error) (dvd_input_t);
  39
  40 #ifdef HAVE_DVDCSS_DVDCSS_H
  41 /* linking to libdvdcss */
  42 #include <dvdcss/dvdcss.h>
  43 #define DVDcss_open(a) dvdcss_open((char*)(a))
  44 #define DVDcss_close   dvdcss_close
  45 #define DVDcss_seek    dvdcss_seek
  46 #define DVDcss_title   dvdcss_title
  47 #define DVDcss_read    dvdcss_read
  48 #define DVDcss_error   dvdcss_error
  49 #else
  50
  51 /* dlopening libdvdcss */
  52 #ifdef HAVE_DLFCN_H
  53 #include <dlfcn.h>
  54 #else
  55 /* Only needed on MINGW at the moment */
  56 #include "../../msvc/contrib/dlfcn.c"
  57 #endif
  58
  59 typedef struct dvdcss_s *dvdcss_handle;
  60 static dvdcss_handle (*DVDcss_open)  (const char *);
  61 static int           (*DVDcss_close) (dvdcss_handle);
  62 static int           (*DVDcss_seek)  (dvdcss_handle, int, int);
  63 static int           (*DVDcss_title) (dvdcss_handle, int);
  64 static int           (*DVDcss_read)  (dvdcss_handle, void *, int, int);
  65 static char *        (*DVDcss_error) (dvdcss_handle);
  66 #endif
  67
  68 /* The DVDinput handle, add stuff here for new input methods. */
  69 struct dvd_input_s {
  70   /* libdvdcss handle */
  71   dvdcss_handle dvdcss;
  72
  73   /* dummy file input */
  74   int fd;
  75 };
  76
  77
  78 /**
  79  * initialize and open a DVD device or file.
  80  */
  81 static dvd_input_t css_open(const char *target)
  82 {
  83   dvd_input_t dev;
  84
  85   /* Allocate the handle structure */
  86   dev = (dvd_input_t) malloc(sizeof(*dev));
  87   if(dev == NULL) {
  88     fprintf(stderr, "libdvdread: Could not allocate memory.\n");
  89     return NULL;
  90   }
  91
  92   /* Really open it with libdvdcss */
  93   dev->dvdcss = DVDcss_open(target);
  94   if(dev->dvdcss == 0) {
  95     fprintf(stderr, "libdvdread: Could not open %s with libdvdcss.\n", target);
  96     free(dev);
  97     return NULL;
  98   }
  99
 100   return dev;
 101 }
 102
 103 /**
 104  * return the last error message
 105  */
 106 static char *css_error(dvd_input_t dev)
 107 {
 108   return DVDcss_error(dev->dvdcss);
 109 }
 110
 111 /**
 112  * seek into the device.
 113  */
 114 static int css_seek(dvd_input_t dev, int blocks)
 115 {
 116   /* DVDINPUT_NOFLAGS should match the DVDCSS_NOFLAGS value. */
 117   return DVDcss_seek(dev->dvdcss, blocks, DVDINPUT_NOFLAGS);
 118 }
 119
 120 /**
 121  * set the block for the beginning of a new title (key).
 122  */
 123 static int css_title(dvd_input_t dev, int block)
 124 {
 125   return DVDcss_title(dev->dvdcss, block);
 126 }
 127
 128 /**
 129  * read data from the device.
 130  */
 131 static int css_read(dvd_input_t dev, void *buffer, int blocks, int flags)
 132 {
 133   return DVDcss_read(dev->dvdcss, buffer, blocks, flags);
 134 }
 135
 136 /**
 137  * close the DVD device and clean up the library.
 138  */
 139 static int css_close(dvd_input_t dev)
 140 {
 141   int ret;
 142
 143   ret = DVDcss_close(dev->dvdcss);
 144
 145   if(ret < 0)
 146     return ret;
 147
 148   free(dev);
 149
 150   return 0;
 151 }
 152
 153 /**
 154  * initialize and open a DVD device or file.
 155  */
 156 static dvd_input_t file_open(const char *target)
 157 {
 158   dvd_input_t dev;
 159
 160   /* Allocate the library structure */
 161   dev = (dvd_input_t) malloc(sizeof(*dev));
 162   if(dev == NULL) {
 163     fprintf(stderr, "libdvdread: Could not allocate memory.\n");
 164     return NULL;
 165   }
 166
 167   /* Open the device */
 168 #if !defined(WIN32) && !defined(__OS2__)
 169   dev->fd = open(target, O_RDONLY);
 170 #else
 171   dev->fd = open(target, O_RDONLY | O_BINARY);
 172 #endif
 173   if(dev->fd < 0) {
 174     perror("libdvdread: Could not open input");
 175     free(dev);
 176     return NULL;
 177   }
 178
 179   return dev;
 180 }
 181
 182 /**
 183  * return the last error message
 184  */
 185 static char *file_error(dvd_input_t dev)
 186 {
 187   /* use strerror(errno)? */
 188   return (char *)"unknown error";
 189 }
 190
 191 /**
 192  * seek into the device.
 193  */
 194 static int file_seek(dvd_input_t dev, int blocks)
 195 {
 196   off_t pos;
 197
 198   pos = lseek(dev->fd, (off_t)blocks * (off_t)DVD_VIDEO_LB_LEN, SEEK_SET);
 199   if(pos < 0) {
 200     return pos;
 201   }
 202   /* assert pos % DVD_VIDEO_LB_LEN == 0 */
 203   return (int) (pos / DVD_VIDEO_LB_LEN);
 204 }
 205
 206 /**
 207  * set the block for the beginning of a new title (key).
 208  */
 209 static int file_title(dvd_input_t dev, int block)
 210 {
 211   return -1;
 212 }
 213
 214 /**
 215  * read data from the device.
 216  */
 217 static int file_read(dvd_input_t dev, void *buffer, int blocks, int flags)
 218 {
 219   size_t len;
 220   ssize_t ret;
 221
 222   len = (size_t)blocks * DVD_VIDEO_LB_LEN;
 223
 224   while(len > 0) {
 225
 226     ret = read(dev->fd, buffer, len);
 227
 228     if(ret < 0) {
 229       /* One of the reads failed, too bad.  We won't even bother
 230        * returning the reads that went OK, and as in the POSIX spec
 231        * the file position is left unspecified after a failure. */
 232       return ret;
 233     }
 234
 235     if(ret == 0) {
 236       /* Nothing more to read.  Return all of the whole blocks, if any.
 237        * Adjust the file position back to the previous block boundary. */
 238       size_t bytes = (size_t)blocks * DVD_VIDEO_LB_LEN - len;
 239       off_t over_read = -(bytes % DVD_VIDEO_LB_LEN);
 240       /*off_t pos =*/ lseek(dev->fd, over_read, SEEK_CUR);
 241       /* should have pos % 2048 == 0 */
 242       return (int) (bytes / DVD_VIDEO_LB_LEN);
 243     }
 244
 245     len -= ret;
 246   }
 247
 248   return blocks;
 249 }
 250
 251 /**
 252  * close the DVD device and clean up.
 253  */
 254 static int file_close(dvd_input_t dev)
 255 {
 256   int ret;
 257
 258   ret = close(dev->fd);
 259
 260   if(ret < 0)
 261     return ret;
 262
 263   free(dev);
 264
 265   return 0;
 266 }
 267
 268
 269 /**
 270  * Setup read functions with either libdvdcss or minimal DVD access.
 271  */
 272 int dvdinput_setup(void)
 273 {
 274   void *dvdcss_library = NULL;
 275   char **dvdcss_version = NULL;
 276
 277 #ifdef HAVE_DVDCSS_DVDCSS_H
 278   /* linking to libdvdcss */
 279   dvdcss_library = &dvdcss_library;  /* Give it some value != NULL */
 280   /* the DVDcss_* functions have been #defined at the top */
 281   dvdcss_version = &dvdcss_interface_2;
 282
 283 #else
 284   /* dlopening libdvdcss */
 285
 286 #ifdef __APPLE__
 287   #define CSS_LIB "libdvdcss.2.dylib"
 288 #elif defined(WIN32)
 289   #define CSS_LIB "libdvdcss.dll"
 290 #elif defined(__OS2__)
 291   #define CSS_LIB "dvdcss.dll"
 292 #else
 293   #define CSS_LIB "libdvdcss.so.2"
 294 #endif
 295   dvdcss_library = dlopen(CSS_LIB, RTLD_LAZY);
 296
 297   if(dvdcss_library != NULL) {
 298 #if defined(__OpenBSD__) && !defined(__ELF__) || defined(__OS2__)
 299 #define U_S "_"
 300 #else
 301 #define U_S
 302 #endif
 303     DVDcss_open = (dvdcss_handle (*)(const char*))
 304       dlsym(dvdcss_library, U_S "dvdcss_open");
 305     DVDcss_close = (int (*)(dvdcss_handle))
 306       dlsym(dvdcss_library, U_S "dvdcss_close");
 307     DVDcss_title = (int (*)(dvdcss_handle, int))
 308       dlsym(dvdcss_library, U_S "dvdcss_title");
 309     DVDcss_seek = (int (*)(dvdcss_handle, int, int))
 310       dlsym(dvdcss_library, U_S "dvdcss_seek");
 311     DVDcss_read = (int (*)(dvdcss_handle, void*, int, int))
 312       dlsym(dvdcss_library, U_S "dvdcss_read");
 313     DVDcss_error = (char* (*)(dvdcss_handle))
 314       dlsym(dvdcss_library, U_S "dvdcss_error");
 315
 316     dvdcss_version = (char **)dlsym(dvdcss_library, U_S "dvdcss_interface_2");
 317
 318     if(dlsym(dvdcss_library, U_S "dvdcss_crack")) {
 319       fprintf(stderr,
 320               "libdvdread: Old (pre-0.0.2) version of libdvdcss found.\n"
 321               "libdvdread: You should get the latest version from "
 322               "http://www.videolan.org/\n" );
 323       dlclose(dvdcss_library);
 324       dvdcss_library = NULL;
 325     } else if(!DVDcss_open  || !DVDcss_close || !DVDcss_title || !DVDcss_seek
 326               || !DVDcss_read || !DVDcss_error || !dvdcss_version) {
 327       fprintf(stderr,  "libdvdread: Missing symbols in %s, "
 328               "this shouldn't happen !\n", CSS_LIB);
 329       dlclose(dvdcss_library);
 330     }
 331   }
 332 #endif /* HAVE_DVDCSS_DVDCSS_H */
 333
 334   if(dvdcss_library != NULL) {
 335     /*
 336     char *psz_method = getenv( "DVDCSS_METHOD" );
 337     char *psz_verbose = getenv( "DVDCSS_VERBOSE" );
 338     fprintf(stderr, "DVDCSS_METHOD %s\n", psz_method);
 339     fprintf(stderr, "DVDCSS_VERBOSE %s\n", psz_verbose);
 340     */
 341     fprintf(stderr, "libdvdread: Using libdvdcss version %s for DVD access\n",
 342             dvdcss_version ? *dvdcss_version : "");
 343
 344     /* libdvdcss wrapper functions */
 345     dvdinput_open  = css_open;
 346     dvdinput_close = css_close;
 347     dvdinput_seek  = css_seek;
 348     dvdinput_title = css_title;
 349     dvdinput_read  = css_read;
 350     dvdinput_error = css_error;
 351     return 1;
 352
 353   } else {
 354     fprintf(stderr, "libdvdread: Encrypted DVD support unavailable.\n");
 355
 356     /* libdvdcss replacement functions */
 357     dvdinput_open  = file_open;
 358     dvdinput_close = file_close;
 359     dvdinput_seek  = file_seek;
 360     dvdinput_title = file_title;
 361     dvdinput_read  = file_read;
 362     dvdinput_error = file_error;
 363     return 0;
 364   }
 365 }