[v2.0.3][Issue #8] Added --without-sentinel configure option to disable variadic argument sentinels

Author: Snaipe

.gitignore

@@ -16,6 +16,6 @@
 !configure.ac
 !autogen.sh
 
-src/config.h
+include/csptr/config.h
 *~
 *.swp

Makefile.am

@@ -22,6 +22,7 @@ EXTRA_DIST = LICENSE README.md
 
 subdirincludedir = $(includedir)/csptr/
 subdirinclude_HEADERS = \
+	include/csptr/config.h \
 	include/csptr/smalloc.h \
 	include/csptr/array.h \
 	include/csptr/smart_ptr.h

configure.ac

@@ -1,6 +1,6 @@
 AC_PREREQ([2.60])
 
-AC_INIT([csptr], [2.0.1], [], [csptr], [franklinmathieu@gmail.com])
+AC_INIT([csptr], [2.0.3], [], [csptr], [franklinmathieu@gmail.com])
 AC_CONFIG_SRCDIR([src/mman.c])
 
 LT_PREREQ([2.2.4])
@@ -35,6 +35,13 @@ AC_ARG_WITH([fixed-allocator],
     [AC_DEFINE([SMALLOC_FIXED_ALLOCATOR], [1], [Define if malloc should always be used.])],
     [])
 
+AC_ARG_WITH([sentinel],
+    AS_HELP_STRING([--without-sentinel], [Disable the sentinel used for variadic function arguments]))
+
+AS_IF([test "x$with_sentinel" = "xno"], [
+  AC_DEFINE([CSPTR_NO_SENTINEL], [1], [Define if a sentinel should not be used for variadic function arguments.])
+])
+
 AC_ARG_ENABLE([gcov],
   [AS_HELP_STRING([--enable-gcov],
     [Compile the project with converage enabled])],
@@ -56,7 +63,7 @@ case "`uname`" in
     ;;
 esac
 
-AC_CONFIG_HEADERS([src/config.h])
+AC_CONFIG_HEADERS([include/csptr/config.h])
 AC_CONFIG_FILES([Makefile check/Makefile])
 
 AC_OUTPUT

include/csptr/smalloc.h

@@ -27,6 +27,22 @@
 
 # include <stdlib.h>
 
+# ifndef CSPTR_CONFIG_H_
+#  define CSPTR_CONFIG_H_
+#  include "config.h"
+# endif
+
+# ifdef CSPTR_NO_SENTINEL
+#  ifndef __GNUC__
+#   error Variadic structure sentinels can only be disabled on a compiler supporting GNU extensions
+#  endif
+#  define CSPTR_SENTINEL
+#  define CSPTR_SENTINEL_DEC
+# else
+#  define CSPTR_SENTINEL        .sentinel_ = 0,
+#  define CSPTR_SENTINEL_DEC int sentinel_;
+# endif
+
 enum pointer_kind {
     UNIQUE,
     SHARED,
@@ -44,7 +60,7 @@ typedef struct {
 extern s_allocator smalloc_allocator;
 
 typedef struct {
-    int sentinel_;
+    CSPTR_SENTINEL_DEC
     size_t size;
     size_t nmemb;
     enum pointer_kind kind;
@@ -62,7 +78,7 @@ __attribute__((malloc))
 void *smalloc(s_smalloc_args *args);
 void sfree(void *ptr);
 
-# define smalloc(...) \
-    smalloc(&(s_smalloc_args) { .sentinel_ = 0, __VA_ARGS__ })
+#  define smalloc(...) \
+    smalloc(&(s_smalloc_args) { CSPTR_SENTINEL __VA_ARGS__ })
 
 #endif /* !CSPTR_SMALLOC_H_ */

include/csptr/smart_ptr.h

@@ -41,15 +41,15 @@ inline void sfree_stack(void *ptr) {
 # define smart_ptr(Kind, Type, Args...)                                     \
     ({                                                                      \
         struct s_tmp {                                                      \
-            int sentinel_;                                                  \
+            CSPTR_SENTINEL_DEC                                              \
             __typeof__(Type) value;                                         \
             f_destructor dtor;                                              \
             struct {                                                        \
                 const void *ptr;                                            \
                 size_t size;                                                \
             } meta;                                                         \
         } args = {                                                          \
-            .sentinel_ = 0,                                                 \
+            CSPTR_SENTINEL                                                  \
             Args                                                            \
         };                                                                  \
         const __typeof__(Type[1]) dummy;                                    \
@@ -65,15 +65,15 @@ inline void sfree_stack(void *ptr) {
 # define smart_arr(Kind, Type, Length, Args...)                             \
     ({                                                                      \
         struct s_tmp {                                                      \
-            int sentinel_;                                                  \
+            CSPTR_SENTINEL_DEC                                              \
             __typeof__(__typeof__(Type)[Length]) value;                     \
             f_destructor dtor;                                              \
             struct {                                                        \
                 const void *ptr;                                            \
                 size_t size;                                                \
             } meta;                                                         \
         } args = {                                                          \
-            .sentinel_ = 0,                                                 \
+            CSPTR_SENTINEL                                                  \
             Args                                                            \
         };                                                                  \
         void *var = smalloc(sizeof (Type), Length, Kind, ARGS_);            \

src/mman.c

@@ -28,7 +28,6 @@
 #include <string.h>
 #include <assert.h>
 
-#include "config.h"
 #include "mman.h"
 #include "array.h"
 #undef smalloc