misc/libfreetype/src/base/ftstream.c
changeset 5172 88f2e05288ba
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libfreetype/src/base/ftstream.c	Mon Apr 25 01:46:54 2011 +0200
@@ -0,0 +1,864 @@
+/***************************************************************************/
+/*                                                                         */
+/*  ftstream.c                                                             */
+/*                                                                         */
+/*    I/O stream support (body).                                           */
+/*                                                                         */
+/*  Copyright 2000-2002, 2004-2006, 2008-2011 by                           */
+/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
+/*                                                                         */
+/*  This file is part of the FreeType project, and may only be used,       */
+/*  modified, and distributed under the terms of the FreeType project      */
+/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
+/*  this file you indicate that you have read the license and              */
+/*  understand and accept it fully.                                        */
+/*                                                                         */
+/***************************************************************************/
+
+
+#include <ft2build.h>
+#include FT_INTERNAL_STREAM_H
+#include FT_INTERNAL_DEBUG_H
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
+  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
+  /* messages during execution.                                            */
+  /*                                                                       */
+#undef  FT_COMPONENT
+#define FT_COMPONENT  trace_stream
+
+
+  FT_BASE_DEF( void )
+  FT_Stream_OpenMemory( FT_Stream       stream,
+                        const FT_Byte*  base,
+                        FT_ULong        size )
+  {
+    stream->base   = (FT_Byte*) base;
+    stream->size   = size;
+    stream->pos    = 0;
+    stream->cursor = 0;
+    stream->read   = 0;
+    stream->close  = 0;
+  }
+
+
+  FT_BASE_DEF( void )
+  FT_Stream_Close( FT_Stream  stream )
+  {
+    if ( stream && stream->close )
+      stream->close( stream );
+  }
+
+
+  FT_BASE_DEF( FT_Error )
+  FT_Stream_Seek( FT_Stream  stream,
+                  FT_ULong   pos )
+  {
+    FT_Error  error = FT_Err_Ok;
+
+
+    if ( stream->read )
+    {
+      if ( stream->read( stream, pos, 0, 0 ) )
+      {
+        FT_ERROR(( "FT_Stream_Seek:"
+                   " invalid i/o; pos = 0x%lx, size = 0x%lx\n",
+                   pos, stream->size ));
+
+        error = FT_Err_Invalid_Stream_Operation;
+      }
+    }
+    /* note that seeking to the first position after the file is valid */
+    else if ( pos > stream->size )
+    {
+      FT_ERROR(( "FT_Stream_Seek:"
+                 " invalid i/o; pos = 0x%lx, size = 0x%lx\n",
+                 pos, stream->size ));
+
+      error = FT_Err_Invalid_Stream_Operation;
+    }
+
+    if ( !error )
+      stream->pos = pos;
+
+    return error;
+  }
+
+
+  FT_BASE_DEF( FT_Error )
+  FT_Stream_Skip( FT_Stream  stream,
+                  FT_Long    distance )
+  {
+    if ( distance < 0 )
+      return FT_Err_Invalid_Stream_Operation;
+
+    return FT_Stream_Seek( stream, (FT_ULong)( stream->pos + distance ) );
+  }
+
+
+  FT_BASE_DEF( FT_Long )
+  FT_Stream_Pos( FT_Stream  stream )
+  {
+    return stream->pos;
+  }
+
+
+  FT_BASE_DEF( FT_Error )
+  FT_Stream_Read( FT_Stream  stream,
+                  FT_Byte*   buffer,
+                  FT_ULong   count )
+  {
+    return FT_Stream_ReadAt( stream, stream->pos, buffer, count );
+  }
+
+
+  FT_BASE_DEF( FT_Error )
+  FT_Stream_ReadAt( FT_Stream  stream,
+                    FT_ULong   pos,
+                    FT_Byte*   buffer,
+                    FT_ULong   count )
+  {
+    FT_Error  error = FT_Err_Ok;
+    FT_ULong  read_bytes;
+
+
+    if ( pos >= stream->size )
+    {
+      FT_ERROR(( "FT_Stream_ReadAt:"
+                 " invalid i/o; pos = 0x%lx, size = 0x%lx\n",
+                 pos, stream->size ));
+
+      return FT_Err_Invalid_Stream_Operation;
+    }
+
+    if ( stream->read )
+      read_bytes = stream->read( stream, pos, buffer, count );
+    else
+    {
+      read_bytes = stream->size - pos;
+      if ( read_bytes > count )
+        read_bytes = count;
+
+      FT_MEM_COPY( buffer, stream->base + pos, read_bytes );
+    }
+
+    stream->pos = pos + read_bytes;
+
+    if ( read_bytes < count )
+    {
+      FT_ERROR(( "FT_Stream_ReadAt:"
+                 " invalid read; expected %lu bytes, got %lu\n",
+                 count, read_bytes ));
+
+      error = FT_Err_Invalid_Stream_Operation;
+    }
+
+    return error;
+  }
+
+
+  FT_BASE_DEF( FT_ULong )
+  FT_Stream_TryRead( FT_Stream  stream,
+                     FT_Byte*   buffer,
+                     FT_ULong   count )
+  {
+    FT_ULong  read_bytes = 0;
+
+
+    if ( stream->pos >= stream->size )
+      goto Exit;
+
+    if ( stream->read )
+      read_bytes = stream->read( stream, stream->pos, buffer, count );
+    else
+    {
+      read_bytes = stream->size - stream->pos;
+      if ( read_bytes > count )
+        read_bytes = count;
+
+      FT_MEM_COPY( buffer, stream->base + stream->pos, read_bytes );
+    }
+
+    stream->pos += read_bytes;
+
+  Exit:
+    return read_bytes;
+  }
+
+
+  FT_BASE_DEF( FT_Error )
+  FT_Stream_ExtractFrame( FT_Stream  stream,
+                          FT_ULong   count,
+                          FT_Byte**  pbytes )
+  {
+    FT_Error  error;
+
+
+    error = FT_Stream_EnterFrame( stream, count );
+    if ( !error )
+    {
+      *pbytes = (FT_Byte*)stream->cursor;
+
+      /* equivalent to FT_Stream_ExitFrame(), with no memory block release */
+      stream->cursor = 0;
+      stream->limit  = 0;
+    }
+
+    return error;
+  }
+
+
+  FT_BASE_DEF( void )
+  FT_Stream_ReleaseFrame( FT_Stream  stream,
+                          FT_Byte**  pbytes )
+  {
+    if ( stream && stream->read )
+    {
+      FT_Memory  memory = stream->memory;
+
+#ifdef FT_DEBUG_MEMORY
+      ft_mem_free( memory, *pbytes );
+      *pbytes = NULL;
+#else
+      FT_FREE( *pbytes );
+#endif
+    }
+    *pbytes = 0;
+  }
+
+
+  FT_BASE_DEF( FT_Error )
+  FT_Stream_EnterFrame( FT_Stream  stream,
+                        FT_ULong   count )
+  {
+    FT_Error  error = FT_Err_Ok;
+    FT_ULong  read_bytes;
+
+
+    /* check for nested frame access */
+    FT_ASSERT( stream && stream->cursor == 0 );
+
+    if ( stream->read )
+    {
+      /* allocate the frame in memory */
+      FT_Memory  memory = stream->memory;
+
+
+      /* simple sanity check */
+      if ( count > stream->size )
+      {
+        FT_ERROR(( "FT_Stream_EnterFrame:"
+                   " frame size (%lu) larger than stream size (%lu)\n",
+                   count, stream->size ));
+
+        error = FT_Err_Invalid_Stream_Operation;
+        goto Exit;
+      }
+
+#ifdef FT_DEBUG_MEMORY
+      /* assume _ft_debug_file and _ft_debug_lineno are already set */
+      stream->base = (unsigned char*)ft_mem_qalloc( memory, count, &error );
+      if ( error )
+        goto Exit;
+#else
+      if ( FT_QALLOC( stream->base, count ) )
+        goto Exit;
+#endif
+      /* read it */
+      read_bytes = stream->read( stream, stream->pos,
+                                 stream->base, count );
+      if ( read_bytes < count )
+      {
+        FT_ERROR(( "FT_Stream_EnterFrame:"
+                   " invalid read; expected %lu bytes, got %lu\n",
+                   count, read_bytes ));
+
+        FT_FREE( stream->base );
+        error = FT_Err_Invalid_Stream_Operation;
+      }
+      stream->cursor = stream->base;
+      stream->limit  = stream->cursor + count;
+      stream->pos   += read_bytes;
+    }
+    else
+    {
+      /* check current and new position */
+      if ( stream->pos >= stream->size        ||
+           stream->size - stream->pos < count )
+      {
+        FT_ERROR(( "FT_Stream_EnterFrame:"
+                   " invalid i/o; pos = 0x%lx, count = %lu, size = 0x%lx\n",
+                   stream->pos, count, stream->size ));
+
+        error = FT_Err_Invalid_Stream_Operation;
+        goto Exit;
+      }
+
+      /* set cursor */
+      stream->cursor = stream->base + stream->pos;
+      stream->limit  = stream->cursor + count;
+      stream->pos   += count;
+    }
+
+  Exit:
+    return error;
+  }
+
+
+  FT_BASE_DEF( void )
+  FT_Stream_ExitFrame( FT_Stream  stream )
+  {
+    /* IMPORTANT: The assertion stream->cursor != 0 was removed, given    */
+    /*            that it is possible to access a frame of length 0 in    */
+    /*            some weird fonts (usually, when accessing an array of   */
+    /*            0 records, like in some strange kern tables).           */
+    /*                                                                    */
+    /*  In this case, the loader code handles the 0-length table          */
+    /*  gracefully; however, stream.cursor is really set to 0 by the      */
+    /*  FT_Stream_EnterFrame() call, and this is not an error.            */
+    /*                                                                    */
+    FT_ASSERT( stream );
+
+    if ( stream->read )
+    {
+      FT_Memory  memory = stream->memory;
+
+#ifdef FT_DEBUG_MEMORY
+      ft_mem_free( memory, stream->base );
+      stream->base = NULL;
+#else
+      FT_FREE( stream->base );
+#endif
+    }
+    stream->cursor = 0;
+    stream->limit  = 0;
+  }
+
+
+  FT_BASE_DEF( FT_Char )
+  FT_Stream_GetChar( FT_Stream  stream )
+  {
+    FT_Char  result;
+
+
+    FT_ASSERT( stream && stream->cursor );
+
+    result = 0;
+    if ( stream->cursor < stream->limit )
+      result = *stream->cursor++;
+
+    return result;
+  }
+
+
+  FT_BASE_DEF( FT_UShort )
+  FT_Stream_GetUShort( FT_Stream  stream )
+  {
+    FT_Byte*  p;
+    FT_Short  result;
+
+
+    FT_ASSERT( stream && stream->cursor );
+
+    result         = 0;
+    p              = stream->cursor;
+    if ( p + 1 < stream->limit )
+      result       = FT_NEXT_USHORT( p );
+    stream->cursor = p;
+
+    return result;
+  }
+
+
+  FT_BASE_DEF( FT_UShort )
+  FT_Stream_GetUShortLE( FT_Stream  stream )
+  {
+    FT_Byte*  p;
+    FT_Short  result;
+
+
+    FT_ASSERT( stream && stream->cursor );
+
+    result         = 0;
+    p              = stream->cursor;
+    if ( p + 1 < stream->limit )
+      result       = FT_NEXT_USHORT_LE( p );
+    stream->cursor = p;
+
+    return result;
+  }
+
+
+  FT_BASE_DEF( FT_ULong )
+  FT_Stream_GetUOffset( FT_Stream  stream )
+  {
+    FT_Byte*  p;
+    FT_Long   result;
+
+
+    FT_ASSERT( stream && stream->cursor );
+
+    result         = 0;
+    p              = stream->cursor;
+    if ( p + 2 < stream->limit )
+      result       = FT_NEXT_UOFF3( p );
+    stream->cursor = p;
+    return result;
+  }
+
+
+  FT_BASE_DEF( FT_ULong )
+  FT_Stream_GetULong( FT_Stream  stream )
+  {
+    FT_Byte*  p;
+    FT_Long   result;
+
+
+    FT_ASSERT( stream && stream->cursor );
+
+    result         = 0;
+    p              = stream->cursor;
+    if ( p + 3 < stream->limit )
+      result       = FT_NEXT_ULONG( p );
+    stream->cursor = p;
+    return result;
+  }
+
+
+  FT_BASE_DEF( FT_ULong )
+  FT_Stream_GetULongLE( FT_Stream  stream )
+  {
+    FT_Byte*  p;
+    FT_Long   result;
+
+
+    FT_ASSERT( stream && stream->cursor );
+
+    result         = 0;
+    p              = stream->cursor;
+    if ( p + 3 < stream->limit )
+      result       = FT_NEXT_ULONG_LE( p );
+    stream->cursor = p;
+    return result;
+  }
+
+
+  FT_BASE_DEF( FT_Char )
+  FT_Stream_ReadChar( FT_Stream  stream,
+                      FT_Error*  error )
+  {
+    FT_Byte  result = 0;
+
+
+    FT_ASSERT( stream );
+
+    *error = FT_Err_Ok;
+
+    if ( stream->read )
+    {
+      if ( stream->read( stream, stream->pos, &result, 1L ) != 1L )
+        goto Fail;
+    }
+    else
+    {
+      if ( stream->pos < stream->size )
+        result = stream->base[stream->pos];
+      else
+        goto Fail;
+    }
+    stream->pos++;
+
+    return result;
+
+  Fail:
+    *error = FT_Err_Invalid_Stream_Operation;
+    FT_ERROR(( "FT_Stream_ReadChar:"
+               " invalid i/o; pos = 0x%lx, size = 0x%lx\n",
+               stream->pos, stream->size ));
+
+    return 0;
+  }
+
+
+  FT_BASE_DEF( FT_UShort )
+  FT_Stream_ReadUShort( FT_Stream  stream,
+                       FT_Error*  error )
+  {
+    FT_Byte   reads[2];
+    FT_Byte*  p = 0;
+    FT_Short  result = 0;
+
+
+    FT_ASSERT( stream );
+
+    *error = FT_Err_Ok;
+
+    if ( stream->pos + 1 < stream->size )
+    {
+      if ( stream->read )
+      {
+        if ( stream->read( stream, stream->pos, reads, 2L ) != 2L )
+          goto Fail;
+
+        p = reads;
+      }
+      else
+      {
+        p = stream->base + stream->pos;
+      }
+
+      if ( p )
+        result = FT_NEXT_USHORT( p );
+    }
+    else
+      goto Fail;
+
+    stream->pos += 2;
+
+    return result;
+
+  Fail:
+    *error = FT_Err_Invalid_Stream_Operation;
+    FT_ERROR(( "FT_Stream_ReadUShort:"
+               " invalid i/o; pos = 0x%lx, size = 0x%lx\n",
+               stream->pos, stream->size ));
+
+    return 0;
+  }
+
+
+  FT_BASE_DEF( FT_UShort )
+  FT_Stream_ReadUShortLE( FT_Stream  stream,
+                         FT_Error*  error )
+  {
+    FT_Byte   reads[2];
+    FT_Byte*  p = 0;
+    FT_Short  result = 0;
+
+
+    FT_ASSERT( stream );
+
+    *error = FT_Err_Ok;
+
+    if ( stream->pos + 1 < stream->size )
+    {
+      if ( stream->read )
+      {
+        if ( stream->read( stream, stream->pos, reads, 2L ) != 2L )
+          goto Fail;
+
+        p = reads;
+      }
+      else
+      {
+        p = stream->base + stream->pos;
+      }
+
+      if ( p )
+        result = FT_NEXT_USHORT_LE( p );
+    }
+    else
+      goto Fail;
+
+    stream->pos += 2;
+
+    return result;
+
+  Fail:
+    *error = FT_Err_Invalid_Stream_Operation;
+    FT_ERROR(( "FT_Stream_ReadUShortLE:"
+               " invalid i/o; pos = 0x%lx, size = 0x%lx\n",
+               stream->pos, stream->size ));
+
+    return 0;
+  }
+
+
+  FT_BASE_DEF( FT_ULong )
+  FT_Stream_ReadUOffset( FT_Stream  stream,
+                        FT_Error*  error )
+  {
+    FT_Byte   reads[3];
+    FT_Byte*  p = 0;
+    FT_Long   result = 0;
+
+
+    FT_ASSERT( stream );
+
+    *error = FT_Err_Ok;
+
+    if ( stream->pos + 2 < stream->size )
+    {
+      if ( stream->read )
+      {
+        if (stream->read( stream, stream->pos, reads, 3L ) != 3L )
+          goto Fail;
+
+        p = reads;
+      }
+      else
+      {
+        p = stream->base + stream->pos;
+      }
+
+      if ( p )
+        result = FT_NEXT_UOFF3( p );
+    }
+    else
+      goto Fail;
+
+    stream->pos += 3;
+
+    return result;
+
+  Fail:
+    *error = FT_Err_Invalid_Stream_Operation;
+    FT_ERROR(( "FT_Stream_ReadUOffset:"
+               " invalid i/o; pos = 0x%lx, size = 0x%lx\n",
+               stream->pos, stream->size ));
+
+    return 0;
+  }
+
+
+  FT_BASE_DEF( FT_ULong )
+  FT_Stream_ReadULong( FT_Stream  stream,
+                      FT_Error*  error )
+  {
+    FT_Byte   reads[4];
+    FT_Byte*  p = 0;
+    FT_Long   result = 0;
+
+
+    FT_ASSERT( stream );
+
+    *error = FT_Err_Ok;
+
+    if ( stream->pos + 3 < stream->size )
+    {
+      if ( stream->read )
+      {
+        if ( stream->read( stream, stream->pos, reads, 4L ) != 4L )
+          goto Fail;
+
+        p = reads;
+      }
+      else
+      {
+        p = stream->base + stream->pos;
+      }
+
+      if ( p )
+        result = FT_NEXT_ULONG( p );
+    }
+    else
+      goto Fail;
+
+    stream->pos += 4;
+
+    return result;
+
+  Fail:
+    *error = FT_Err_Invalid_Stream_Operation;
+    FT_ERROR(( "FT_Stream_ReadULong:"
+               " invalid i/o; pos = 0x%lx, size = 0x%lx\n",
+               stream->pos, stream->size ));
+
+    return 0;
+  }
+
+
+  FT_BASE_DEF( FT_ULong )
+  FT_Stream_ReadULongLE( FT_Stream  stream,
+                        FT_Error*  error )
+  {
+    FT_Byte   reads[4];
+    FT_Byte*  p = 0;
+    FT_Long   result = 0;
+
+
+    FT_ASSERT( stream );
+
+    *error = FT_Err_Ok;
+
+    if ( stream->pos + 3 < stream->size )
+    {
+      if ( stream->read )
+      {
+        if ( stream->read( stream, stream->pos, reads, 4L ) != 4L )
+          goto Fail;
+
+        p = reads;
+      }
+      else
+      {
+        p = stream->base + stream->pos;
+      }
+
+      if ( p )
+        result = FT_NEXT_ULONG_LE( p );
+    }
+    else
+      goto Fail;
+
+    stream->pos += 4;
+
+    return result;
+
+  Fail:
+    *error = FT_Err_Invalid_Stream_Operation;
+    FT_ERROR(( "FT_Stream_ReadULongLE:"
+               " invalid i/o; pos = 0x%lx, size = 0x%lx\n",
+               stream->pos, stream->size ));
+
+    return 0;
+  }
+
+
+  FT_BASE_DEF( FT_Error )
+  FT_Stream_ReadFields( FT_Stream              stream,
+                        const FT_Frame_Field*  fields,
+                        void*                  structure )
+  {
+    FT_Error  error;
+    FT_Bool   frame_accessed = 0;
+    FT_Byte*  cursor;
+
+    if ( !fields || !stream )
+      return FT_Err_Invalid_Argument;
+
+    cursor = stream->cursor;
+
+    error = FT_Err_Ok;
+    do
+    {
+      FT_ULong  value;
+      FT_Int    sign_shift;
+      FT_Byte*  p;
+
+
+      switch ( fields->value )
+      {
+      case ft_frame_start:  /* access a new frame */
+        error = FT_Stream_EnterFrame( stream, fields->offset );
+        if ( error )
+          goto Exit;
+
+        frame_accessed = 1;
+        cursor         = stream->cursor;
+        fields++;
+        continue;  /* loop! */
+
+      case ft_frame_bytes:  /* read a byte sequence */
+      case ft_frame_skip:   /* skip some bytes      */
+        {
+          FT_UInt  len = fields->size;
+
+
+          if ( cursor + len > stream->limit )
+          {
+            error = FT_Err_Invalid_Stream_Operation;
+            goto Exit;
+          }
+
+          if ( fields->value == ft_frame_bytes )
+          {
+            p = (FT_Byte*)structure + fields->offset;
+            FT_MEM_COPY( p, cursor, len );
+          }
+          cursor += len;
+          fields++;
+          continue;
+        }
+
+      case ft_frame_byte:
+      case ft_frame_schar:  /* read a single byte */
+        value = FT_NEXT_BYTE(cursor);
+        sign_shift = 24;
+        break;
+
+      case ft_frame_short_be:
+      case ft_frame_ushort_be:  /* read a 2-byte big-endian short */
+        value = FT_NEXT_USHORT(cursor);
+        sign_shift = 16;
+        break;
+
+      case ft_frame_short_le:
+      case ft_frame_ushort_le:  /* read a 2-byte little-endian short */
+        value = FT_NEXT_USHORT_LE(cursor);
+        sign_shift = 16;
+        break;
+
+      case ft_frame_long_be:
+      case ft_frame_ulong_be:  /* read a 4-byte big-endian long */
+        value = FT_NEXT_ULONG(cursor);
+        sign_shift = 0;
+        break;
+
+      case ft_frame_long_le:
+      case ft_frame_ulong_le:  /* read a 4-byte little-endian long */
+        value = FT_NEXT_ULONG_LE(cursor);
+        sign_shift = 0;
+        break;
+
+      case ft_frame_off3_be:
+      case ft_frame_uoff3_be:  /* read a 3-byte big-endian long */
+        value = FT_NEXT_UOFF3(cursor);
+        sign_shift = 8;
+        break;
+
+      case ft_frame_off3_le:
+      case ft_frame_uoff3_le:  /* read a 3-byte little-endian long */
+        value = FT_NEXT_UOFF3_LE(cursor);
+        sign_shift = 8;
+        break;
+
+      default:
+        /* otherwise, exit the loop */
+        stream->cursor = cursor;
+        goto Exit;
+      }
+
+      /* now, compute the signed value is necessary */
+      if ( fields->value & FT_FRAME_OP_SIGNED )
+        value = (FT_ULong)( (FT_Int32)( value << sign_shift ) >> sign_shift );
+
+      /* finally, store the value in the object */
+
+      p = (FT_Byte*)structure + fields->offset;
+      switch ( fields->size )
+      {
+      case (8 / FT_CHAR_BIT):
+        *(FT_Byte*)p = (FT_Byte)value;
+        break;
+
+      case (16 / FT_CHAR_BIT):
+        *(FT_UShort*)p = (FT_UShort)value;
+        break;
+
+      case (32 / FT_CHAR_BIT):
+        *(FT_UInt32*)p = (FT_UInt32)value;
+        break;
+
+      default:  /* for 64-bit systems */
+        *(FT_ULong*)p = (FT_ULong)value;
+      }
+
+      /* go to next field */
+      fields++;
+    }
+    while ( 1 );
+
+  Exit:
+    /* close the frame if it was opened by this read */
+    if ( frame_accessed )
+      FT_Stream_ExitFrame( stream );
+
+    return error;
+  }
+
+
+/* END */