libmtp.c

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/**
 * \file libmtp.c
 * This file provides an interface "glue" to the underlying
 * PTP implementation from libgphoto2. It uses some local
 * code to convert from/to UTF-8 (stored in unicode.c/.h)
 * and some small utility functions, mainly for debugging
 * (stored in util.c/.h).
 *
 * The three PTP files (ptp.c, ptp.h and ptp-pack.c) are
 * plain copied from the libhphoto2 codebase.
 *
 * The files libusb-glue.c/.h are just what they say: an
 * interface to libusb for the actual, physical USB traffic.
 */
#include "libmtp.h"
#include "unicode.h"
#include "ptp.h"
#include "libusb-glue.h"

#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef _MSC_VER // For MSVC++
#define USE_WINDOWS_IO_H
#include <io.h>
#endif

/* Enable enhanced MTP commands */
#define ENABLE_MTP_ENHANCED

/*
 * On MacOS (Darwin) and *BSD we're not using glibc, but libiconv.
 * glibc knows that UCS-2 is to be in the local machine endianness,
 * whereas libiconv does not. So we construct this macro to get
 * things right. Reportedly, glibc 2.1.3 has a bug so that UCS-2
 * is always bigendian though, we would need to work around that
 * too...
 */
#ifndef __GLIBC__
#define UCS_2_INTERNAL "UCS-2-INTERNAL"
#else
#if (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 1 )
#error "Too old glibc. This versions iconv() implementation cannot be trusted."
#endif
#define UCS_2_INTERNAL "UCS-2"
#endif

/*
 * This is a mapping between libmtp internal MTP filetypes and
 * the libgphoto2/PTP equivalent defines. We need this because
 * otherwise the libmtp.h device has to be dependent on ptp.h
 * to be installed too, and we don't want that.
 */
//typedef struct filemap_struct filemap_t;
typedef struct filemap_struct {
  char *description; /**< Text description for the file type */
  LIBMTP_filetype_t id; /**< LIBMTP internal type for the file type */
  uint16_t ptp_id; /**< PTP ID for the filetype */
  struct filemap_struct *next;
} filemap_t;

// Global variables
// This holds the global filetype mapping table
static filemap_t *filemap = NULL;

/*
 * Forward declarations of local (static) functions.
 */
static int register_filetype(char const * const description, LIBMTP_filetype_t const id,
			     uint16_t const ptp_id);
static void init_filemap();
static void flush_handles(LIBMTP_mtpdevice_t *device);
static int check_if_file_fits(LIBMTP_mtpdevice_t *device, uint64_t const filesize);
static uint16_t map_libmtp_type_to_ptp_type(LIBMTP_filetype_t intype);
static LIBMTP_filetype_t map_ptp_type_to_libmtp_type(uint16_t intype);
static int get_device_unicode_property(LIBMTP_mtpdevice_t *device,
				       char **unicstring, uint16_t property);
static char *get_string_from_object(LIBMTP_mtpdevice_t *device, uint32_t const object_id,
				    uint16_t const attribute_id);
static uint32_t get_u32_from_object(LIBMTP_mtpdevice_t *device,uint32_t const object_id,
				    uint16_t const attribute_id, uint32_t const value_default);
static uint16_t get_u16_from_object(LIBMTP_mtpdevice_t *device, uint32_t const object_id,
				    uint16_t const attribute_id, uint16_t const value_default);
static uint8_t get_u8_from_object(LIBMTP_mtpdevice_t *device, uint32_t const object_id,
				  uint16_t const attribute_id, uint8_t const value_default);
static int set_object_string(LIBMTP_mtpdevice_t *device, uint32_t const object_id,
			     uint16_t const attribute_id, char const * const string);
static int set_object_u32(LIBMTP_mtpdevice_t *device, uint32_t const object_id,
			  uint16_t const attribute_id, uint32_t const value);
static int set_object_u16(LIBMTP_mtpdevice_t *device, uint32_t const object_id,
			  uint16_t const attribute_id, uint16_t const value);
static int set_object_u8(LIBMTP_mtpdevice_t *device, uint32_t const object_id,
			 uint16_t const attribute_id, uint8_t const value);
static void get_track_metadata(LIBMTP_mtpdevice_t *device, uint16_t objectformat,
			       LIBMTP_track_t *track);
static int create_new_abstract_list(LIBMTP_mtpdevice_t *device,
				    char const * const name,
				    uint32_t const parenthandle,
				    uint16_t const objectformat,
				    char const * const suffix,
				    uint32_t * const newid,
				    uint32_t const * const tracks,
				    uint32_t const no_tracks);
static MTPPropList *New_MTP_Prop_Entry();
static void Destroy_MTP_Prop_Entry(MTPPropList *prop);

/**
 * Create a new file mapping entry
 * @return a newly allocated filemapping entry.
 */
static filemap_t *new_filemap_entry()
{
  filemap_t *filemap;

  filemap = (filemap_t *)malloc(sizeof(filemap_t));

  if( filemap != NULL ) {
    filemap->description = NULL;
    filemap->id = LIBMTP_FILETYPE_UNKNOWN;
    filemap->ptp_id = PTP_OFC_Undefined;
    filemap->next = NULL;
  }

  return filemap;
}

/**
 * Register an MTP or PTP filetype for data retrieval
 *
 * @param description Text description of filetype
 * @param id libmtp internal filetype id
 * @param ptp_id PTP filetype id
 * @return 0 for success any other value means error.
*/
static int register_filetype(char const * const description, LIBMTP_filetype_t const id,
			     uint16_t const ptp_id)
{
  filemap_t *new = NULL, *current;

  // Has this LIBMTP filetype been registered before ?
  current = filemap;
  while (current != NULL) {
    if(current->id == id) {
      break;
    }
    current = current->next;
  }

  // Create the entry
  if(current == NULL) {
    new = new_filemap_entry();
    if(new == NULL) {
      return 1;
    }

    new->id = id;
    if(description != NULL) {
      new->description = strdup(description);
    }
    new->ptp_id = ptp_id;

    // Add the entry to the list
    if(filemap == NULL) {
      filemap = new;
    } else {
      current = filemap;
      while (current->next != NULL ) current=current->next;
      current->next = new;
    }
    // Update the existing entry
  } else {
    if (current->description != NULL) {
      free(current->description);
    }
    current->description = NULL;
    if(description != NULL) {
      current->description = strdup(description);
    }
    current->ptp_id = ptp_id;
  }

  return 0;
}

static void init_filemap()
{
  register_filetype("RIFF WAVE file", LIBMTP_FILETYPE_WAV, PTP_OFC_WAV);
  register_filetype("ISO MPEG Audio Layer 3", LIBMTP_FILETYPE_MP3, PTP_OFC_MP3);
  register_filetype("Microsoft Windows Media Audio", LIBMTP_FILETYPE_WMA, PTP_OFC_MTP_WMA);
  register_filetype("Ogg container format", LIBMTP_FILETYPE_OGG, PTP_OFC_MTP_OGG);
  register_filetype("Audible.com Audio Codec", LIBMTP_FILETYPE_AUDIBLE, PTP_OFC_MTP_AudibleCodec);
  register_filetype("Advanced Acoustic Coding", LIBMTP_FILETYPE_MP4, PTP_OFC_MTP_MP4);
  register_filetype("Undefined audio file", LIBMTP_FILETYPE_UNDEF_AUDIO, PTP_OFC_MTP_UndefinedAudio);
  register_filetype("Microsoft Windows Media Video", LIBMTP_FILETYPE_WMV, PTP_OFC_MTP_WMV);
  register_filetype("Audio Video Interleave", LIBMTP_FILETYPE_AVI, PTP_OFC_AVI);
  register_filetype("MPEG video stream", LIBMTP_FILETYPE_MPEG, PTP_OFC_MPEG);
  register_filetype("Microsoft Advanced Systems Format", LIBMTP_FILETYPE_ASF, PTP_OFC_ASF);
  register_filetype("Apple Quicktime container format", LIBMTP_FILETYPE_QT, PTP_OFC_QT);
  register_filetype("Undefined video file", LIBMTP_FILETYPE_UNDEF_VIDEO, PTP_OFC_MTP_UndefinedVideo);
  register_filetype("JPEG file", LIBMTP_FILETYPE_JPEG, PTP_OFC_EXIF_JPEG);
  register_filetype("JFIF file", LIBMTP_FILETYPE_JFIF, PTP_OFC_JFIF);
  register_filetype("TIFF bitmap file", LIBMTP_FILETYPE_TIFF, PTP_OFC_TIFF);
  register_filetype("BMP bitmap file", LIBMTP_FILETYPE_BMP, PTP_OFC_BMP);
  register_filetype("GIF bitmap file", LIBMTP_FILETYPE_GIF, PTP_OFC_GIF);
  register_filetype("PICT bitmap file", LIBMTP_FILETYPE_PICT, PTP_OFC_PICT);
  register_filetype("Portable Network Graphics", LIBMTP_FILETYPE_PNG, PTP_OFC_PNG);
  register_filetype("Microsoft Windows Image Format", LIBMTP_FILETYPE_WINDOWSIMAGEFORMAT, PTP_OFC_MTP_WindowsImageFormat);
  register_filetype("VCalendar version 1", LIBMTP_FILETYPE_VCALENDAR1, PTP_OFC_MTP_vCalendar1);
  register_filetype("VCalendar version 2", LIBMTP_FILETYPE_VCALENDAR2, PTP_OFC_MTP_vCalendar2);
  register_filetype("VCard version 2", LIBMTP_FILETYPE_VCARD2, PTP_OFC_MTP_vCard2);
  register_filetype("VCard version 3", LIBMTP_FILETYPE_VCARD3, PTP_OFC_MTP_vCard3);
  register_filetype("Undefined Windows executable file", LIBMTP_FILETYPE_WINEXEC, PTP_OFC_MTP_UndefinedWindowsExecutable);
  register_filetype("Text file", LIBMTP_FILETYPE_TEXT, PTP_OFC_Text);
  register_filetype("HTML file", LIBMTP_FILETYPE_HTML, PTP_OFC_HTML);
  register_filetype("Undefined filetype", LIBMTP_FILETYPE_UNKNOWN, PTP_OFC_Undefined);
}

/**
 * Returns the PTP filetype that maps to a certain libmtp internal file type.
 * @param intype the MTP library interface type
 * @return the PTP (libgphoto2) interface type
 */
static uint16_t map_libmtp_type_to_ptp_type(LIBMTP_filetype_t intype)
{
  filemap_t *current;

  current = filemap;

  while (current != NULL) {
    if(current->id == intype) {
      return current->ptp_id;
    }
    current = current->next;
  }
  // printf("map_libmtp_type_to_ptp_type: unknown filetype.\n");
  return PTP_OFC_Undefined;
}


/**
 * Returns the PTP internal filetype that maps to a certain libmtp
 * interface file type.
 * @param intype the PTP (libgphoto2) interface type
 * @return the MTP library interface type
 */
static LIBMTP_filetype_t map_ptp_type_to_libmtp_type(uint16_t intype)
{
  filemap_t *current;

  current = filemap;

  while (current != NULL) {
    if(current->ptp_id == intype) {
      return current->id;
    }
    current = current->next;
  }
  // printf("map_ptp_type_to_libmtp_type: unknown filetype.\n");
  return LIBMTP_FILETYPE_UNKNOWN;
}


/**
 * Initialize the library. You are only supposed to call this
 * one, before using the library for the first time in a program.
 * Never re-initialize libmtp!
 *
 * The only thing this does at the moment is to initialise the
 * filetype mapping table.
 */
void LIBMTP_Init(void)
{
  init_filemap();
  return;
}


/**
 * This helper function returns a textual description for a libmtp
 * file type to be used in dialog boxes etc.
 * @param intype the libmtp internal filetype to get a description for.
 * @return a string representing the filetype, this must <b>NOT</b>
 *         be free():ed by the caller!
 */
char const * LIBMTP_Get_Filetype_Description(LIBMTP_filetype_t intype)
{
  filemap_t *current;

  current = filemap;

  while (current != NULL) {
    if(current->id == intype) {
      return current->description;
    }
    current = current->next;
  }

  return "Unknown filetype";
}


/**
 * Retrieves a string from an object
 *
 * @param device a pointer to an MTP device.
 * @param object_id Object reference
 * @param attribute_id PTP attribute ID
 * @return valid string or NULL on failure. The returned string
 *         must bee <code>free()</code>:ed by the caller after
 *         use.
 */
static char *get_string_from_object(LIBMTP_mtpdevice_t *device, uint32_t const object_id,
				    uint16_t const attribute_id)
{
  PTPPropertyValue propval;
  char *retstring = NULL;
  PTPParams *params = (PTPParams *) device->params;
  uint16_t ret;

  if ( device == NULL || object_id == 0) {
    return NULL;
  }

  ret = ptp_mtp_getobjectpropvalue(params, object_id, attribute_id, &propval, PTP_DTC_STR);
  if (ret == PTP_RC_OK) {
    if (propval.str != NULL) {
      retstring = (char *) strdup(propval.str);
      free(propval.str);
    }
  }

  return retstring;
}

/**
 * Retrieves an unsigned 32-bit integer from an object attribute
 *
 * @param device a pointer to an MTP device.
 * @param object_id Object reference
 * @param attribute_id PTP attribute ID
 * @param value_default Default value to return on failure
 * @return the value
 */
static uint32_t get_u32_from_object(LIBMTP_mtpdevice_t *device,uint32_t const object_id,
				    uint16_t const attribute_id, uint32_t const value_default)
{
  PTPPropertyValue propval;
  uint32_t retval = value_default;
  PTPParams *params = (PTPParams *) device->params;
  uint16_t ret;

  if ( device == NULL ) {
    return value_default;
  }

  ret = ptp_mtp_getobjectpropvalue(params, object_id,
                                   attribute_id,
                                   &propval,
                                   PTP_DTC_UINT32);
  if (ret == PTP_RC_OK) {
    retval = propval.u32;
  }

  return retval;
}

/**
 * Retrieves an unsigned 16-bit integer from an object attribute
 *
 * @param device a pointer to an MTP device.
 * @param object_id Object reference
 * @param attribute_id PTP attribute ID
 * @param value_default Default value to return on failure
 * @return a value
 */
static uint16_t get_u16_from_object(LIBMTP_mtpdevice_t *device, uint32_t const object_id,
				    uint16_t const attribute_id, uint16_t const value_default)
{
  PTPPropertyValue propval;
  uint16_t retval = value_default;
  PTPParams *params = (PTPParams *) device->params;
  uint16_t ret;

  if ( device == NULL ) {
    return value_default;
  }

  ret = ptp_mtp_getobjectpropvalue(params, object_id,
                                   attribute_id,
                                   &propval,
                                   PTP_DTC_UINT16);
  if (ret == PTP_RC_OK) {
    retval = propval.u16;
  }

  return retval;
}

/**
 * Retrieves an unsigned 8-bit integer from an object attribute
 *
 * @param device a pointer to an MTP device.
 * @param object_id Object reference