[devel] Prevent unexpected API exports from non-libpng DLLs on Windows.
The "_DLL" is removed from the test of whether a DLL is being built.
diff --git a/ANNOUNCE b/ANNOUNCE
index f33cdb1..9a3192e 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
-Libpng 1.5.5beta05 - July 29, 2011
+Libpng 1.5.5beta05 - August 17, 2011
This is not intended to be a public release. It will be replaced
within a few weeks by a public version or by another test version.
@@ -45,7 +45,21 @@
Updated commentary about the png_rgb_to_gray() default coefficients
in the manual and in pngrtran.c
-Version 1.5.5beta05 [July 29, 2011]
+Version 1.5.5beta05 [August 17, 2011]
+ Prevent unexpected API exports from non-libpng DLLs on Windows. The "_DLL"
+ is removed from the test of whether a DLL is being built (this erroneously
+ caused the libpng APIs to be marked as DLL exports in static builds under
+ Microsoft Visual Studio). Almost all of the libpng building configuration
+ is moved from pngconf.h to pngpriv.h, but PNG_DLL_EXPORT remains in
+ pngconf.h, though, so that it is colocated with the import definition (it
+ is no longer used anywhere in the installed headers). The VStudio project
+ definitions have been cleaned up: "_USRDLL" has been removed from the
+ static library builds (this was incorrect), and PNG_USE_DLL has been added
+ to pngvalid to test the functionality (pngtest does not supply it,
+ deliberately). The spurious "_EXPORTS" has been removed from the
+ libpng build (all these errors were a result of copy/paste between project
+ configurations.)
+
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diff --git a/CHANGES b/CHANGES
index a55a850..a463383 100644
--- a/CHANGES
+++ b/CHANGES
@@ -3529,7 +3529,20 @@
Updated commentary about the png_rgb_to_gray() default coefficients
in the manual and in pngrtran.c
-Version 1.5.5beta05 [July 29, 2011]
+Version 1.5.5beta05 [August 17, 2011]
+ Prevent unexpected API exports from non-libpng DLLs on Windows. The "_DLL"
+ is removed from the test of whether a DLL is being built (this erroneously
+ caused the libpng APIs to be marked as DLL exports in static builds under
+ Microsoft Visual Studio). Almost all of the libpng building configuration
+ is moved from pngconf.h to pngpriv.h, but PNG_DLL_EXPORT remains in
+ pngconf.h, though, so that it is colocated with the import definition (it
+ is no longer used anywhere in the installed headers). The VStudio project
+ definitions have been cleaned up: "_USRDLL" has been removed from the
+ static library builds (this was incorrect), and PNG_USE_DLL has been added
+ to pngvalid to test the functionality (pngtest does not supply it,
+ deliberately). The spurious "_EXPORTS" has been removed from the
+ libpng build (all these errors were a result of copy/paste between project
+ configurations.)
Send comments/corrections/commendations to png-mng-implement at lists.sf.net
(subscription required; visit
diff --git a/pngconf.h b/pngconf.h
index c087df3..cd183e3 100644
--- a/pngconf.h
+++ b/pngconf.h
@@ -1,7 +1,7 @@
/* pngconf.h - machine configurable file for libpng
*
- * libpng version 1.5.5beta05 - July 29, 2011
+ * libpng version 1.5.5beta05 - August 17, 2011
*
* Copyright (c) 1998-2011 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -164,7 +164,9 @@
* 'type', compiler specific.
*
* PNG_DLL_EXPORT Set to the magic to use during a libpng build to
- * make a symbol exported from the DLL.
+ * make a symbol exported from the DLL. Not used in the
+ * public header files; see pngpriv.h for how it is used
+ * in the libpng build.
*
* PNG_DLL_IMPORT Set to the magic to force the libpng symbols to come
* from a DLL - used to define PNG_IMPEXP when
@@ -258,25 +260,14 @@
# define PNGAPI PNGCAPI
#endif
-/* The default for PNG_IMPEXP depends on whether the library is
- * being built or used.
+/* PNG_IMPEXP may be set on the compilation system command line or (if not set)
+ * then in an internal header file when building the library, otherwise (when
+ * using the library) it is set here.
*/
#ifndef PNG_IMPEXP
-# ifdef PNGLIB_BUILD
- /* Building the library */
-# if (defined(DLL_EXPORT)/*from libtool*/ ||\
- defined(_WINDLL) || defined(_DLL) || defined(__DLL__) ||\
- defined(_USRDLL) ||\
- defined(PNG_BUILD_DLL)) && defined(PNG_DLL_EXPORT)
- /* Building a DLL. */
-# define PNG_IMPEXP PNG_DLL_EXPORT
-# endif /* DLL */
-# else
- /* Using the library */
-# if defined(PNG_USE_DLL) && defined(PNG_DLL_IMPORT)
- /* This forces use of a DLL, disallowing static linking */
-# define PNG_IMPEXP PNG_DLL_IMPORT
-# endif
+# if defined(PNG_USE_DLL) && defined(PNG_DLL_IMPORT)
+ /* This forces use of a DLL, disallowing static linking */
+# define PNG_IMPEXP PNG_DLL_IMPORT
# endif
# ifndef PNG_IMPEXP
@@ -356,25 +347,18 @@
# ifndef PNG_ALLOCATED
# define PNG_ALLOCATED __attribute__((__malloc__))
# endif
-
- /* This specifically protects structure members that should only be
- * accessed from within the library, therefore should be empty during
- * a library build.
- */
-# ifndef PNGLIB_BUILD
-# ifndef PNG_DEPRECATED
-# define PNG_DEPRECATED __attribute__((__deprecated__))
+# ifndef PNG_DEPRECATED
+# define PNG_DEPRECATED __attribute__((__deprecated__))
+# endif
+# ifndef PNG_PRIVATE
+# if 0 /* Doesn't work so we use deprecated instead*/
+# define PNG_PRIVATE \
+ __attribute__((warning("This function is not exported by libpng.")))
+# else
+# define PNG_PRIVATE \
+ __attribute__((__deprecated__))
# endif
-# ifndef PNG_PRIVATE
-# if 0 /* Doesn't work so we use deprecated instead*/
-# define PNG_PRIVATE \
- __attribute__((warning("This function is not exported by libpng.")))
-# else
-# define PNG_PRIVATE \
- __attribute__((__deprecated__))
-# endif
-# endif
-# endif /* PNGLIB_BUILD */
+# endif
# endif /* __GNUC__ */
# if defined(_MSC_VER) && (_MSC_VER >= 1300)
@@ -389,19 +373,12 @@
# define PNG_ALLOCATED __declspec(restrict)
# endif
# endif
-
- /* This specifically protects structure members that should only be
- * accessed from within the library, therefore should be empty during
- * a library build.
- */
-# ifndef PNGLIB_BUILD
-# ifndef PNG_DEPRECATED
-# define PNG_DEPRECATED __declspec(deprecated)
-# endif
-# ifndef PNG_PRIVATE
-# define PNG_PRIVATE __declspec(deprecated)
-# endif
-# endif /* PNGLIB_BUILD */
+# ifndef PNG_DEPRECATED
+# define PNG_DEPRECATED __declspec(deprecated)
+# endif
+# ifndef PNG_PRIVATE
+# define PNG_PRIVATE __declspec(deprecated)
+# endif
# endif /* _MSC_VER */
#endif /* PNG_PEDANTIC_WARNINGS */
diff --git a/pngpriv.h b/pngpriv.h
index 5b4d212..f38d603 100644
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -44,7 +44,8 @@
*/
#include <stdlib.h>
-#define PNGLIB_BUILD
+#define PNGLIB_BUILD /*libpng is being built, not used*/
+
#ifdef PNG_USER_CONFIG
# include "pngusr.h"
/* These should have been defined in pngusr.h */
@@ -55,10 +56,80 @@
# define PNG_USER_DLLFNAME_POSTFIX "Cb"
# endif
#endif
+
+/* Is this a build of a DLL where compilation of the object modules requires
+ * different preprocessor settings to those required for a simple library? If
+ * so PNG_BUILD_DLL must be set.
+ *
+ * If libpng is used inside a DLL but that DLL does not export the libpng APIs
+ * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a
+ * static library of libpng then link the DLL against that.
+ */
+#ifndef PNG_BUILD_DLL
+# ifdef DLL_EXPORT
+ /* This is set by libtool when files are compiled for a DLL; libtool
+ * always compiles twice, even on systems where it isn't necessary. Set
+ * PNG_BUILD_DLL in case it is necessary:
+ */
+# define PNG_BUILD_DLL
+# else
+# ifdef _WINDLL
+ /* This is set by the Microsoft Visual Studio IDE in projects that
+ * build a DLL. It can't easily be removed from those projects (it
+ * isn't visible in the Visual Studio UI) so it is a fairly reliable
+ * indication that PNG_IMPEXP needs to be set to the DLL export
+ * attributes.
+ */
+# define PNG_BUILD_DLL
+# else
+# ifdef __DLL__
+ /* This is set by the Borland C system when compiling for a DLL
+ * (as above.)
+ */
+# define PNG_BUILD_DLL
+# else
+ /* Add additional compiler cases here. */
+# endif
+# endif
+# endif
+#endif /* Setting PNG_BUILD_DLL if required */
+
+/* See pngconf.h for more details: the builder of the library may set this on
+ * the command line to the right thing for the specific compilation system or it
+ * may be automagically set above (at present we know of no system where it does
+ * need to be set on the command line.)
+ *
+ * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
+ * setting it to the "import" setting for a DLL build.
+ */
+#ifndef PNG_IMPEXP
+# ifdef PNG_BUILD_DLL
+# define PNG_IMPEXP PNG_DLL_EXPORT
+# else
+ /* Not building a DLL, or the DLL doesn't require specific export
+ * definitions.
+ */
+# define PNG_IMPEXP
+# endif
+#endif
+
+/* No warnings for private or deprecated functions in the build: */
+#ifndef PNG_DEPRECATED
+# define PNG_DEPRECATED
+#endif
+#ifndef PNG_PRIVATE
+# define PNG_PRIVATE
+#endif
+
#include "png.h"
#include "pnginfo.h"
#include "pngstruct.h"
+/* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
+#ifndef PNG_DLL_EXPORT
+# define PNG_DLL_EXPORT
+#endif
+
/* This is used for 16 bit gamma tables - only the top level pointers are const,
* this could be changed:
*/
@@ -1078,6 +1149,7 @@
unsigned long *hi_product, unsigned long *lo_product));
#endif
+#ifdef PNG_cHRM_SUPPORTED
/* Added at libpng version 1.4.0 */
PNG_EXTERN void png_check_IHDR PNGARG((png_structp png_ptr,
png_uint_32 width, png_uint_32 height, int bit_depth,
diff --git a/projects/vstudio/libpng/libpng.vcxproj b/projects/vstudio/libpng/libpng.vcxproj
index 6977900..c4bf041 100644
--- a/projects/vstudio/libpng/libpng.vcxproj
+++ b/projects/vstudio/libpng/libpng.vcxproj
@@ -118,7 +118,7 @@
<DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
<Optimization>Disabled</Optimization>
<BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
- <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+ <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<IntrinsicFunctions>true</IntrinsicFunctions>
<FunctionLevelLinking>true</FunctionLevelLinking>
<FloatingPointExceptions>false</FloatingPointExceptions>
@@ -175,7 +175,7 @@
<RuntimeLibrary>MultiThreaded</RuntimeLibrary>
<FunctionLevelLinking>true</FunctionLevelLinking>
<IntrinsicFunctions>true</IntrinsicFunctions>
- <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+ <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<FloatingPointExceptions>false</FloatingPointExceptions>
<TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
<PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
diff --git a/projects/vstudio/pngvalid/pngvalid.vcxproj b/projects/vstudio/pngvalid/pngvalid.vcxproj
index 79fd1bd..bd85806 100644
--- a/projects/vstudio/pngvalid/pngvalid.vcxproj
+++ b/projects/vstudio/pngvalid/pngvalid.vcxproj
@@ -81,7 +81,7 @@
<DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
<Optimization>Disabled</Optimization>
<BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
- <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+ <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
<DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
<CompileAsManaged>false</CompileAsManaged>
@@ -146,7 +146,7 @@
<Optimization>Full</Optimization>
<FunctionLevelLinking>false</FunctionLevelLinking>
<IntrinsicFunctions>true</IntrinsicFunctions>
- <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+ <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
<DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
<CompileAsManaged>false</CompileAsManaged>
diff --git a/projects/vstudio/readme.txt b/projects/vstudio/readme.txt
index 2231f4a..2b4766f 100644
--- a/projects/vstudio/readme.txt
+++ b/projects/vstudio/readme.txt
@@ -1,7 +1,7 @@
VisualStudio instructions
-libpng version 1.5.5beta05 - July 29, 2011
+libpng version 1.5.5beta05 - August 17, 2011
Copyright (c) 1998-2010 Glenn Randers-Pehrson
diff --git a/projects/vstudio/zlib.props b/projects/vstudio/zlib.props
index 524b4dd..636b360 100644
--- a/projects/vstudio/zlib.props
+++ b/projects/vstudio/zlib.props
@@ -2,7 +2,7 @@
<!--
* zlib.props - location of zlib source
*
- * libpng version 1.5.5beta05 - July 29, 2011
+ * libpng version 1.5.5beta05 - August 17, 2011
*
* Copyright (c) 1998-2011 Glenn Randers-Pehrson
*
diff --git a/projects/vstudio/zlib/zlib.vcxproj b/projects/vstudio/zlib/zlib.vcxproj
index aa125de..d627817 100644
--- a/projects/vstudio/zlib/zlib.vcxproj
+++ b/projects/vstudio/zlib/zlib.vcxproj
@@ -84,7 +84,7 @@
</PropertyGroup>
<ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
<ClCompile>
- <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+ <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
<WarningLevel>TurnOffAllWarnings</WarningLevel>
<DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
@@ -99,7 +99,7 @@
</ItemDefinitionGroup>
<ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
<ClCompile>
- <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+ <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<WarningLevel>TurnOffAllWarnings</WarningLevel>
<DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
<Optimization>Disabled</Optimization>
@@ -156,7 +156,7 @@
</ItemDefinitionGroup>
<ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
<ClCompile>
- <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;_USRDLL;DEBUGZLIB_EXPORTS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+ <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<WarningLevel>Level3</WarningLevel>
<DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
</ClCompile>
