(*
 * unbuffered io for ffmpeg system
 * copyright (c) 2001 Fabrice Bellard
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
                                                                              *)

(* This is a part of Pascal porting of ffmpeg.  Originally by Victor Zinetz for Delphi and Free Pascal on Windows.
For Mac OS X, some modifications were made by The Creative CAT, denoted as CAT
in the source codes *)

unit avio;
{$IFDEF FPC}
  {$MODE DELPHI } (* CAT *)
  {$PACKENUM 4}    (* every enum type variables uses 4 bytes, CAT *)
  {$PACKRECORDS C}    (* GCC compatible, Record Packing, CAT *)
{$ENDIF}

interface       (* Widows unit is deleted by CAT *)

const
(* version numbers are changed by The Creative CAT *)

{$IFDEF win32}
  av__format = 'avformat-50.dll';
{$ELSE}
  av__format = 'libavformat.so';   // .0d
//av__format = 'libavformat.51';
{$ENDIF}


  URL_RDONLY = 0;
  URL_WRONLY = 1;
  URL_RDWR   = 2;

(* output byte stream handling *)

type
  offset_t = int64;
  int = integer;

(* unbuffered I/O *)
  PURLProtocol = ^TURLProtocol;
  PURLContext = ^TURLContext;
  TURLContext = record
    prot: PURLProtocol;
    flags: int;
    is_streamed: int;  //* true if streamed (no seek possible), default = false */
    max_packet_size: int;  //* if non zero, the stream is packetized with this max packet size */
    priv_data: pointer;
    filename: array [0..0] of char; (* specified filename *)
  end;

  PURLPollEntry = ^TURLPollEntry;
  TURLPollEntry = record
    handle: PURLContext;
    events: integer;
    revents: integer;
  end;

  TURLProtocol = record
    name: pchar;
    url_open: function (h: PURLContext; const filename: pchar; flags: integer): integer; cdecl;
    url_read: function (h: PURLContext; buf: pchar; size: integer): integer; cdecl;
    url_write: function (h: PURLContext; buf: pchar; size: integer): integer; cdecl;
    url_seek: function (h: PURLContext; pos: int64; whence: integer): int64; cdecl;
    url_close: function (h: PURLContext): integer; cdecl;
    next: PURLProtocol;
  end;

  PByteIOContext = ^TByteIOContext;
  TByteIOContext = record
    buffer: pchar;
    buffer_size: integer;
    buf_ptr: pchar;
    buf_end: pchar;
    opaque: pointer;
    read_packet: function (opaque: pointer; buf: pchar; buf_size: integer): integer; cdecl;
    write_packet: function (opaque: pointer; buf: pchar; buf_size: integer): integer; cdecl;
    seek: function (opaque: pointer; offset: int64; whence: integer): int64; cdecl;
    pos: int64; (* position in the file of the current buffer *)
    must_flush: integer; (* true if the next seek should flush *)
    eof_reached: integer; (* true if eof reached *)
    write_flag: integer;  (* true if open for writing *)
    is_streamed: integer;
    max_packet_size: integer;
    checksum: longword;
    checksum_ptr: pchar;
    update_checksum: function (checksum: cardinal; const buf: pchar; size: cardinal): LongWord; cdecl;
    error: integer;         ///< contains the error code or 0 if no error happened
  end;

  function url_open(h: PPointer; const filename: pchar; flags: integer): integer;
    cdecl; external av__format;
  function url_read (h: PURLContext; buf: pchar; size: integer): integer;
    cdecl; external av__format;
  function url_write (h: PURLContext; buf: pchar; size: integer): integer;
    cdecl; external av__format;
  function url_seek (h: PURLContext; pos: int64; whence: integer): int64;
    cdecl; external av__format;
  function url_close (h: PURLContext): integer;
    cdecl; external av__format;
  function url_exist(const filename: pchar): integer;
    cdecl; external av__format;
  function url_filesize (h: PURLContext): int64;
    cdecl; external av__format;
  function url_get_max_packet_size(h: PURLContext): integer;
    cdecl; external av__format;
  procedure url_get_filename(h: PURLContext; buf: pchar; buf_size: integer);
    cdecl; external av__format;

(* the callback is called in blocking functions to test regulary if
   asynchronous interruption is needed. -EINTR is returned in this
   case by the interrupted function. 'NULL' means no interrupt
   callback is given. *)
  procedure url_set_interrupt_cb (interrupt_cb: pinteger);
    cdecl; external av__format;

(* not implemented *)
//int url_poll(URLPollEntry *poll_table, int n, int timeout);

  function register_protocol (protocol: PURLProtocol): integer;
    cdecl; external av__format;

  function init_put_byte(s: PByteIOContext;
                  buffer: pchar;
                  buffer_size: integer; write_flag: integer;
                  opaque: pointer;
                  read_packet: pointer; //int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
                  write_packet: pointer; //int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
                  seek: pointer //offset_t (*seek)(void *opaque, offset_t offset, int whence)
                  ): integer;
    cdecl; external av__format;
  procedure put_byte(s: PByteIOContext; b: integer);
    cdecl; external av__format;
  procedure put_buffer (s: PByteIOContext; const buf: pchar; size: integer);
    cdecl; external av__format;
  procedure put_le64(s: PByteIOContext; val: int64);
    cdecl; external av__format;
  procedure put_be64(s: PByteIOContext; val: int64);
    cdecl; external av__format;
  procedure put_le32(s: PByteIOContext; val: cardinal);
    cdecl; external av__format;
  procedure put_be32(s: PByteIOContext; val: cardinal);
    cdecl; external av__format;
  procedure put_be24(s: PByteIOContext; val: cardinal);
    cdecl; external av__format;
  procedure put_le16(s: PByteIOContext; val: cardinal);
    cdecl; external av__format;
  procedure put_be16(s: PByteIOContext; val: cardinal);
    cdecl; external av__format;
  procedure put_tag(s: PByteIOContext; const tag: pchar);
    cdecl; external av__format;

  procedure put_strz(s: PByteIOContext; const buf: pchar);
    cdecl; external av__format;

  function url_fseek(s: PByteIOContext; offset: int64; whence: integer): int64;
    cdecl; external av__format;
  procedure url_fskip(s: PByteIOContext; offset: int64);
    cdecl; external av__format;
  function url_ftell(s: PByteIOContext): int64;
    cdecl; external av__format;
  function url_fsize(s: PByteIOContext): int64;
    cdecl; external av__format;
  function url_feof(s: PByteIOContext): integer;
    cdecl; external av__format;
  function url_ferror(s: PByteIOContext): integer;
    cdecl; external av__format;

  procedure put_flush_packet (s: PByteIOContext);
    cdecl; external av__format;
  function get_buffer(s: PByteIOContext; buf: pchar; size: integer): integer;
    cdecl; external av__format;
  function get_partial_buffer(s: PByteIOContext; buf: pchar; size: integer): integer;
    cdecl; external av__format;
  function get_byte(s: PByteIOContext): integer;
    cdecl; external av__format;
  function get_le32(s: PByteIOContext): cardinal;
    cdecl; external av__format;
  function get_le64(s: PByteIOContext): int64;
    cdecl; external av__format;
  function get_le16(s: PByteIOContext): cardinal;
    cdecl; external av__format;

  function get_strz(s: PByteIOContext; buf: pchar; maxlen: integer): pchar;
    cdecl; external av__format;
  function get_be16(s: PByteIOContext): cardinal;
    cdecl; external av__format;
  function get_be24(s: PByteIOContext): cardinal;
    cdecl; external av__format;
  function get_be32(s: PByteIOContext): cardinal;
    cdecl; external av__format;
  function get_be64(s: PByteIOContext): int64;
    cdecl; external av__format;

  function url_is_streamed(s: PByteIOContext): integer;

  function url_fdopen (s: PByteIOContext; h: PURLContext): integer;
    cdecl; external av__format;
  function url_setbufsize (s: PByteIOContext; buf_size: integer): integer;
    cdecl; external av__format;
  function url_fopen(s: PByteIOContext; const filename: pchar; flags: integer): integer;
    cdecl; external av__format;
  function url_fclose(s: PByteIOContext): integer;
    cdecl; external av__format;

  function url_fileno(s: PByteIOContext): PURLContext;
    cdecl; external av__format;
  function url_fget_max_packet_size (s: PByteIOContext): integer;
    cdecl; external av__format;
  function url_open_buf(s: PByteIOContext; buf: pchar; buf_size: integer; flags: integer): integer;
    cdecl; external av__format;
  function url_close_buf(s: PByteIOContext): integer;
    cdecl; external av__format;

  function url_open_dyn_buf(s: PByteIOContext): integer;
    cdecl; external av__format;
  function url_open_dyn_packet_buf(s: PByteIOContext; max_packet_size: integer): integer;
    cdecl; external av__format;
  function url_close_dyn_buf(s: PByteIOContext; pbuffer:PPointer): integer;
    cdecl; external av__format;

  function get_checksum(s: PByteIOContext): cardinal;
    cdecl; external av__format;

  procedure init_checksum (s: PByteIOContext; update_checksum: pointer; checksum: cardinal);
    cdecl; external av__format;

  function udp_set_remote_url(h: PURLContext; const uri: pchar): integer;
    cdecl; external av__format;
  function udp_get_local_port(h: PURLContext): integer;
    cdecl; external av__format;
  function udp_get_file_handle(h: PURLContext): integer;
    cdecl; external av__format;

implementation

function url_is_streamed(s: PByteIOContext): integer;
begin
  Result := s^.is_streamed;
end;

end.