[freetype2] master 5bcaf51: [autofit] Split `afwrtsys.h`.

[Werner Lemberg]

branch: master
commit 5bcaf51b611ce579c89c2bb423984ec89fdaadd7
Author: Ben Wagner <bungeman@chromium.org>
Commit: Werner Lemberg <wl@gnu.org>

    [autofit] Split `afwrtsys.h`.
    
    The header file `afwrtsys.h` has two distinct functions: to include the
    required writing system headers and also to generate code for each writing
    system.  At each current use site only one or the other is used, with
    various macro trickery selecting one or the other.  Split this header into
    `afws-decl.h` for the required writing system declarations and `afws-iter.h`
    for iterating over the writing systems to generate code.
    
    The motivation for this change is that the Visual C++ compiler treats the
    standard include guard idiom like `#pragma once` 'if no non-comment code or
    preprocessor directive comes before or after the standard form of the
    idiom'.  It appears to check this after macro expansion, so if
    `WRITING_SYSTEM` expands to empty the bottom of `afwrtsys.h` is empty and
    looks like the standard include guard idiom which is treated like `#pragma
    once`, so subsequent inclusion of `afwrtsys.h` is elided.
    
    Fixes #1075.
    
    * src/autofit/afglobal.c (af_writing_system_classes), src/autofit/aftypes.h
    (AF_WritingSystem), src/autofit/rules.mk (AUTOF_DRV_H): Updated.
    
    * src/autofit/afwrtsys.h: Split into...
    * src/autofit/afws-decl.h, src/autofit/afws-iter.h: New files.
---
 src/autofit/afglobal.c                  |  8 ++------
 src/autofit/aftypes.h                   |  5 +----
 src/autofit/{afwrtsys.h => afws-decl.h} | 22 +++++-----------------
 src/autofit/{afwrtsys.h => afws-iter.h} | 32 +++++++++-----------------------
 src/autofit/rules.mk                    | 15 ++++++++-------
 5 files changed, 25 insertions(+), 57 deletions(-)

diff --git a/src/autofit/afglobal.c b/src/autofit/afglobal.c
index aedb74d..577b94e 100644
--- a/src/autofit/afglobal.c
+++ b/src/autofit/afglobal.c
@@ -19,6 +19,7 @@
 #include "afglobal.h"
 #include "afranges.h"
 #include "afshaper.h"
+#include "afws-decl.h"
 #include <freetype/internal/ftdebug.h>
 
 
@@ -32,11 +33,6 @@
 #define FT_COMPONENT  afglobal
 
 
-  /* get writing system specific header files */
-#undef  WRITING_SYSTEM
-#define WRITING_SYSTEM( ws, WS )  /* empty */
-#include "afwrtsys.h"
-
 #include "aferrors.h"
 
 
@@ -74,7 +70,7 @@
   af_writing_system_classes[] =
   {
 
-#include "afwrtsys.h"
+#include "afws-iter.h"
 
     NULL  /* do not remove */
   };
diff --git a/src/autofit/aftypes.h b/src/autofit/aftypes.h
index e76b103..1d792b9 100644
--- a/src/autofit/aftypes.h
+++ b/src/autofit/aftypes.h
@@ -198,7 +198,6 @@ extern void*  _af_debug_hints;
    *   outline according to the results of the glyph analyzer.
    */
 
-#define AFWRTSYS_H_  /* don't load header files */
 #undef  WRITING_SYSTEM
 #define WRITING_SYSTEM( ws, WS )    \
           AF_WRITING_SYSTEM_ ## WS,
@@ -207,14 +206,12 @@ extern void*  _af_debug_hints;
   typedef enum  AF_WritingSystem_
   {
 
-#include "afwrtsys.h"
+#include "afws-iter.h"
 
     AF_WRITING_SYSTEM_MAX   /* do not remove */
 
   } AF_WritingSystem;
 
-#undef  AFWRTSYS_H_
-
 
   typedef struct  AF_WritingSystemClassRec_
   {
diff --git a/src/autofit/afwrtsys.h b/src/autofit/afws-decl.h
similarity index 56%
copy from src/autofit/afwrtsys.h
copy to src/autofit/afws-decl.h
index 39aa121..c10dd57 100644
--- a/src/autofit/afwrtsys.h
+++ b/src/autofit/afws-decl.h
@@ -1,8 +1,8 @@
 /****************************************************************************
  *
- * afwrtsys.h
+ * afws-decl.h
  *
- *   Auto-fitter writing systems (specification only).
+ *   Auto-fitter writing system declarations (specification only).
  *
  * Copyright (C) 2013-2021 by
  * David Turner, Robert Wilhelm, and Werner Lemberg.
@@ -16,8 +16,8 @@
  */
 
 
-#ifndef AFWRTSYS_H_
-#define AFWRTSYS_H_
+#ifndef AFWS_DECL_H_
+#define AFWS_DECL_H_
 
   /* Since preprocessor directives can't create other preprocessor */
   /* directives, we have to include the header files manually.     */
@@ -27,19 +27,7 @@
 #include "afcjk.h"
 #include "afindic.h"
 
-#endif /* AFWRTSYS_H_ */
+#endif /* AFWS_DECL_H_ */
 
 
-  /* The following part can be included multiple times. */
-  /* Define `WRITING_SYSTEM' as needed.                 */
-
-
-  /* Add new writing systems here.  The arguments are the writing system */
-  /* name in lowercase and uppercase, respectively.                      */
-
-  WRITING_SYSTEM( dummy,  DUMMY  )
-  WRITING_SYSTEM( latin,  LATIN  )
-  WRITING_SYSTEM( cjk,    CJK    )
-  WRITING_SYSTEM( indic,  INDIC  )
-
 /* END */
diff --git a/src/autofit/afwrtsys.h b/src/autofit/afws-iter.h
similarity index 51%
rename from src/autofit/afwrtsys.h
rename to src/autofit/afws-iter.h
index 39aa121..5571420 100644
--- a/src/autofit/afwrtsys.h
+++ b/src/autofit/afws-iter.h
@@ -1,8 +1,8 @@
 /****************************************************************************
  *
- * afwrtsys.h
+ * afws-iter.h
  *
- *   Auto-fitter writing systems (specification only).
+ *   Auto-fitter writing systems iterator (specification only).
  *
  * Copyright (C) 2013-2021 by
  * David Turner, Robert Wilhelm, and Werner Lemberg.
@@ -15,31 +15,17 @@
  *
  */
 
-
-#ifndef AFWRTSYS_H_
-#define AFWRTSYS_H_
-
-  /* Since preprocessor directives can't create other preprocessor */
-  /* directives, we have to include the header files manually.     */
-
-#include "afdummy.h"
-#include "aflatin.h"
-#include "afcjk.h"
-#include "afindic.h"
-
-#endif /* AFWRTSYS_H_ */
-
-
-  /* The following part can be included multiple times. */
-  /* Define `WRITING_SYSTEM' as needed.                 */
+  /* This header may be included multiple times. */
+  /* Define `WRITING_SYSTEM' as needed.          */
 
 
   /* Add new writing systems here.  The arguments are the writing system */
   /* name in lowercase and uppercase, respectively.                      */
 
-  WRITING_SYSTEM( dummy,  DUMMY  )
-  WRITING_SYSTEM( latin,  LATIN  )
-  WRITING_SYSTEM( cjk,    CJK    )
-  WRITING_SYSTEM( indic,  INDIC  )
+  WRITING_SYSTEM( dummy, DUMMY )
+  WRITING_SYSTEM( latin, LATIN )
+  WRITING_SYSTEM( cjk,   CJK   )
+  WRITING_SYSTEM( indic, INDIC )
+
 
 /* END */
diff --git a/src/autofit/rules.mk b/src/autofit/rules.mk
index 19b3bca..499c0e0 100644
--- a/src/autofit/rules.mk
+++ b/src/autofit/rules.mk
@@ -42,13 +42,14 @@ AUTOF_DRV_SRC := $(AUTOF_DIR)/afblue.c   \
 
 # AUTOF driver headers
 #
-AUTOF_DRV_H := $(AUTOF_DRV_SRC:%c=%h)  \
-               $(AUTOF_DIR)/afcover.h  \
-               $(AUTOF_DIR)/aferrors.h \
-               $(AUTOF_DIR)/afscript.h \
-               $(AUTOF_DIR)/afstyles.h \
-               $(AUTOF_DIR)/aftypes.h  \
-               $(AUTOF_DIR)/afwrtsys.h
+AUTOF_DRV_H := $(AUTOF_DRV_SRC:%c=%h)   \
+               $(AUTOF_DIR)/afcover.h   \
+               $(AUTOF_DIR)/aferrors.h  \
+               $(AUTOF_DIR)/afscript.h  \
+               $(AUTOF_DIR)/afstyles.h  \
+               $(AUTOF_DIR)/aftypes.h   \
+               $(AUTOF_DIR)/afws-decl.h \
+               $(AUTOF_DIR)/afws-iter.h
 
 
 # AUTOF driver object(s)