[master] Revised iTXt support and documentation
diff --git a/ANNOUNCE b/ANNOUNCE
index 8bbc437..144e831 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -100,6 +100,10 @@
been building previous versions with PNG_iTXt_SUPPORTED as well.
version 1.2.41beta11 [November 1, 2009]
+ Revised iTXt support. To ensure binary compatibility with
+ previous versions, the "lang" and "lang_key" members will be assumed
+ to be omitted from previous versions whenever there is a library
+ mismatch.
Send comments/corrections/commendations to png-mng-implement at lists.sf.net
diff --git a/CHANGES b/CHANGES
index b5a8097..6704fe5 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2530,6 +2530,10 @@
been building previous versions with PNG_iTXt_SUPPORTED as well.
version 1.2.41beta11 [November 1, 2009]
+ Revised iTXt support. To ensure binary compatibility with
+ previous versions, the "lang" and "lang_key" members will be assumed
+ to be omitted from previous versions whenever there is a library
+ mismatch.
Send comments/corrections/commendations to png-mng-implement at lists.sf.net
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diff --git a/libpng-1.2.41beta11.txt b/libpng-1.2.41beta11.txt
index 793699a..17b7af2 100644
--- a/libpng-1.2.41beta11.txt
+++ b/libpng-1.2.41beta11.txt
@@ -2951,11 +2951,7 @@
png_malloc_default(), and png_free_default() were added.
Support for the iTXt chunk has been enabled by default as of
-version 1.2.41. If you have been defining PNG_iTXt_SUPPORTED
-already, please continue to do so, as a signal to libpng that your
-previous versions also supported iTXt. If you have not been defining
-PNG_iTXt_SUPPORTED, please don't start now; it will be enabled for
-you by default.
+version 1.2.41.
Support for certain MNG features was enabled.
diff --git a/libpng.3 b/libpng.3
index 8accd5a..2ea3bed 100644
--- a/libpng.3
+++ b/libpng.3
@@ -3772,11 +3772,7 @@
png_malloc_default(), and png_free_default() were added.
Support for the iTXt chunk has been enabled by default as of
-version 1.2.41. If you have been defining PNG_iTXt_SUPPORTED
-already, please continue to do so, as a signal to libpng that your
-previous versions also supported iTXt. If you have not been defining
-PNG_iTXt_SUPPORTED, please don't start now; it will be enabled for
-you by default.
+version 1.2.41.
Support for certain MNG features was enabled.
diff --git a/pngset.c b/pngset.c
index b083b91..c3725d1 100644
--- a/pngset.c
+++ b/pngset.c
@@ -662,18 +662,20 @@
if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
return(0);
-#ifdef PNG_iTXt_NOT_PREVIOUSLY_SUPPORTED
/* If an earlier version of the library was used to build the
* application, it might be using a png_textp structure that
- * does not contain the lang or lang_key elements. If you build
+ * does not contain the lang or lang_key elements. Even if you build
* this library with PNG_iTXt_SUPPORTED explicitly defined,
- * then we assume that your older library was also built with
- * PNG_iTXt_SUPPORTED defined and the complete png_textp structure
- * has existed all along and it's safe to access them. See pngconf.h.
+ * and your older library was also built with PNG_iTXt_SUPPORTED
+ * defined, the complete png_textp structure probably has not existed
+ * all along and it's not safe to access them, due to a bug in
+ * pngconf.h from version 1.2.9 to 1.2.40.
+ *
+ * To do: accept mismatched libraries when both are version 1.2.41
+ * or later.
*/
if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
caller_no_itxt = 1;
-#endif
/* Make sure we have enough space in the "text" array in info_struct
* to hold all of the incoming text_ptr objects.
