ref: a2370f21b5c42dc077ee7be3d5a5d3cb0733d7d7
parent: 154832d466ecca1b473816a0c5422d526180c420
author: Werner Lemberg <wl@gnu.org>
date: Sat Jul 21 03:38:13 EDT 2018
Improve stream extraction macro documentation.
--- a/include/freetype/internal/ftstream.h
+++ b/include/freetype/internal/ftstream.h
@@ -165,6 +165,10 @@
#define FT_BYTE_U32( p, i, s ) ( FT_UINT32( FT_BYTE_( p, i ) ) << (s) )
+ /*
+ * `FT_PEEK_XXX' are generic macros to get data from a buffer position.
+ * No safety checks are performed.
+ */
#define FT_PEEK_SHORT( p ) FT_INT16( FT_BYTE_U16( p, 0, 8 ) | \
FT_BYTE_U16( p, 1, 0 ) )
@@ -213,7 +217,10 @@
FT_BYTE_U32( p, 1, 8 ) | \
FT_BYTE_U32( p, 0, 0 ) )
-
+ /*
+ * `FT_NEXT_XXX' are generic macros to get data from a buffer position
+ * which is then increased appropriately. No safety checks are performed.
+ */
#define FT_NEXT_CHAR( buffer ) \
( (signed char)*buffer++ )
@@ -260,7 +267,11 @@
/**************************************************************************
*
- * Each GET_xxxx() macro uses an implicit `stream' variable.
+ * The `FT_GET_XXX' macros use an implicit `stream' variable.
+ *
+ * Note that a call to `FT_STREAM_SEEK' or `FT_STREAM_POS' has *no* effect
+ * on `FT_GET_XXX'! They operate on `stream->pos', while `FT_GET_XXX' use
+ * `stream->cursor'.
*/
#if 0
#define FT_GET_MACRO( type ) FT_NEXT_ ## type ( stream->cursor )
@@ -299,10 +310,18 @@
#define FT_GET_ULONG_LE() FT_GET_MACRO( FT_Stream_GetULongLE, FT_ULong )
#endif
+
#define FT_READ_MACRO( func, type, var ) \
( var = (type)func( stream, &error ), \
error != FT_Err_Ok )
+ /*
+ * The `FT_READ_XXX' macros use implicit `stream' and `error' variables.
+ *
+ * `FT_READ_XXX' can be controlled with `FT_STREAM_SEEK' and
+ * `FT_STREAM_POS'. They use the full machinery to check whether a read
+ * is valid.
+ */
#define FT_READ_BYTE( var ) FT_READ_MACRO( FT_Stream_ReadChar, FT_Byte, var )
#define FT_READ_CHAR( var ) FT_READ_MACRO( FT_Stream_ReadChar, FT_Char, var )
#define FT_READ_SHORT( var ) FT_READ_MACRO( FT_Stream_ReadUShort, FT_Short, var )
@@ -387,10 +406,10 @@
/* Enter a frame of `count' consecutive bytes in a stream. Returns an */
/* error if the frame could not be read/accessed. The caller can use */
- /* the FT_Stream_Get_XXX functions to retrieve frame data without */
+ /* the `FT_Stream_Get_XXX' functions to retrieve frame data without */
/* error checks. */
/* */
- /* You must _always_ call FT_Stream_ExitFrame() once you have entered */
+ /* You must _always_ call `FT_Stream_ExitFrame' once you have entered */
/* a stream frame! */
/* */
FT_BASE( FT_Error )
@@ -415,7 +434,7 @@
FT_ULong count,
FT_Byte** pbytes );
- /* release an extract frame (see FT_Stream_ExtractFrame) */
+ /* release an extract frame (see `FT_Stream_ExtractFrame') */
FT_BASE( void )
FT_Stream_ReleaseFrame( FT_Stream stream,
FT_Byte** pbytes );
--- a/src/base/ftstream.c
+++ b/src/base/ftstream.c
@@ -219,6 +219,7 @@
{FT_Memory memory = stream->memory;
+
#ifdef FT_DEBUG_MEMORY
ft_mem_free( memory, *pbytes );
*pbytes = NULL;