Store HTML "id" parameter value in wxHtmlCell.

[wxWidgets.git] / src / png / scripts / pnglibconf.dfa

diff --git a/src/png/scripts/pnglibconf.dfa b/src/png/scripts/pnglibconf.dfa
index 07b7f6927a4784663b49708d5a6daf0be92ed886..c95b10255a88f97882aaea34cd28534d5068efca 100644 (file)
--- a/src/png/scripts/pnglibconf.dfa
+++ b/src/png/scripts/pnglibconf.dfa
@@ -6,9 +6,9 @@
 #
 com pnglibconf.h - library build configuration
 com
 #
 com pnglibconf.h - library build configuration
 com

-com libpng version 1.5.3 -  July 7, 2011
+version

 com
 com

-com Copyright (c) 1998-2011 Glenn Randers-Pehrson
+com Copyright (c) 1998-2012 Glenn Randers-Pehrson

 com
 com This code is released under the libpng license.
 com For conditions of distribution and use, see the disclaimer
 com
 com This code is released under the libpng license.
 com For conditions of distribution and use, see the disclaimer


@@ -21,10 +21,10 @@ file pnglibconf.h scripts/pnglibconf.dfa PNGLCONF_H
 # C compiler to generate 'pnglibconf.h' - a list of all the
 # configuration options.  The file lists the various options
 # that can *only* be specified during the libpng build;
 # C compiler to generate 'pnglibconf.h' - a list of all the
 # configuration options.  The file lists the various options
 # that can *only* be specified during the libpng build;

-# pnglibconf.h freezes the definitons selected for the specific
+# pnglibconf.h freezes the definitions selected for the specific

 # build.
 #
 # build.
 #

-# The syntax is detailed in scripts/options.awk, this is a summary
+# The syntax is detailed in scripts/options.awk; this is a summary

 # only:
 #
 # setting <name> [requires ...] [default]
 # only:
 #
 # setting <name> [requires ...] [default]


@@ -32,8 +32,17 @@ file pnglibconf.h scripts/pnglibconf.dfa PNGLCONF_H
 # option <name> [requires ...] [if ...] [enables ...] [disabled]
 #    #define PNG_<name>_SUPPORTED if the requirements are met and
 #    enable the other options listed
 # option <name> [requires ...] [if ...] [enables ...] [disabled]
 #    #define PNG_<name>_SUPPORTED if the requirements are met and
 #    enable the other options listed

-# chunk <name> [requires ...] [disabled]
-#    Enable chunk processing for the given ancillary chunk
+# chunk <name> [requires ...] [enables ...] [disabled]
+#    Enable chunk processing for the given ancillary chunk; any
+#    'requires something' expands to READ_something for read and
+#    WRITE_something for write, but the enables list members are
+#    used as given (e.g. enables GAMMA just expands to that on the
+#    correspond READ_name and WRITE_name lines.)
+#
+# "," may be used to separate options on an 'option' line and is ignored; it
+# doesn't change the meaning of the line.  (NOT setting, where "," becomes
+# part of the setting!)  A comma at the end of an option line causes a
+# continuation (the next line is included in the option too.)

 #
 # Note that the 'on' and 'off' keywords, while valid on both option
 # and chunk, should not be used in this file because they force the
 #
 # Note that the 'on' and 'off' keywords, while valid on both option
 # and chunk, should not be used in this file because they force the


@@ -44,7 +53,7 @@ file pnglibconf.h scripts/pnglibconf.dfa PNGLCONF_H
 # The following setting, option and chunk values can all be changed
 # while building libpng:
 #
 # The following setting, option and chunk values can all be changed
 # while building libpng:
 #

-# setting: change 'setting' lines to fine tune library performance,
+# setting: change 'setting' lines to fine tune library performance;

 #   changes to the settings don't affect the libpng API functionally
 #
 # option: change 'option' lines to remove or add capabilities from
 #   changes to the settings don't affect the libpng API functionally
 #
 # option: change 'option' lines to remove or add capabilities from


@@ -127,6 +136,12 @@ logunsupported = 1
 # - PNG_USER_VERSIONINFO_COMPANYNAME
 # - PNG_USER_VERSIONINFO_LEGALTRADEMARKS
 
 # - PNG_USER_VERSIONINFO_COMPANYNAME
 # - PNG_USER_VERSIONINFO_LEGALTRADEMARKS
 

+# It is necessary to include configures definitions here so that AC_DEFINE
+# in configure.ac works in a comprehensible way
+@#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
+@#  include "config.h"
+@#endif
+

 @#ifdef PNG_USER_CONFIG
 @#  include "pngusr.h"
 @#endif
 @#ifdef PNG_USER_CONFIG
 @#  include "pngusr.h"
 @#endif


@@ -143,6 +158,18 @@ logunsupported = 1
 @#  endif
 @#endif
 
 @#  endif
 @#endif
 

+# This changes the default for the ARM NEON optimizations according to
+# __ARM_NEON__
+@#ifdef __ARM_NEON__
+@#  define PNG_ARM_NEON_SUPPORTED
+@#endif
+
+# IN DEVELOPMENT
+# These are currently experimental features; define them if you want (NOTE:
+# experimental options must be disabled before they are defined in this file!)
+
+# NONE
+

 # Note that PNG_USR_CONFIG only has an effect when building
 # pnglibconf.h
 
 # Note that PNG_USR_CONFIG only has an effect when building
 # pnglibconf.h
 


@@ -161,10 +188,60 @@ setting USER_VERSIONINFO_LEGALTRADEMARKS
 
 setting API_RULE default 0
 
 
 setting API_RULE default 0
 

+# This allows a prefix to be added to the front of every API functon name (and
+# therefore every symbol) by redefining all the function names with the prefix
+# at the end of pnglibconf.h.  It also turns on similar internal symbol renaming
+# by causing a similar build-time only file, pngprefix.h, to be generated.
+
+setting PREFIX
+

 # Default to using the read macros
 
 setting DEFAULT_READ_MACROS default 1
 
 # Default to using the read macros
 
 setting DEFAULT_READ_MACROS default 1
 

+# This setting allows a hardware or configuration specific filter optimization
+# function to be specified, the argument is the name of the filter initializaion
+# function to use.
+
+setting FILTER_OPTIMIZATIONS
+
+# Implementation specific control of the optimizations, enabled by those
+# hardware or software options that need it (typically when run-time choices
+# must be made by the user)
+option SET_OPTION disabled
+
+# These options are specific to the ARM NEON hardware optimizations:
+#
+# ARM_NEON: the optimization itself
+# ARM_NEON_API: allow the optimization to be switched on with png_set_hardware
+# ARM_NEON_CHECK: compile a run-time check to see if Neon extensions are
+#                 supported, this is poorly supported and deprectated - use the
+#                 png_set_hardware API.
+option ARM_NEON disabled,
+   sets FILTER_OPTIMIZATIONS png_init_filter_functions_neon
+option ARM_NEON_API disabled enables SET_OPTION ARM_NEON
+option ARM_NEON_CHECK disabled enables ARM_NEON
+
+# These settings configure the default compression level (0-9) and 'strategy';
+# strategy is as defined by the implementors of zlib, it describes the input
+# data and modifies the zlib parameters in an attempt to optimize the balance
+# between search and huffman encoding in the zlib algorithms.  The defaults are
+# the zlib.h defaults - the apparently recursive definition does not arise
+# because the name of the setting is prefixed by PNG_
+#
+# The TEXT values are the defaults when writing compressed text (all forms)
+#
+# Include the zlib header too, so that the defaults below are known
+@#  include <zlib.h>
+
+# The '@' here means to substitute the value when pnglibconf.h is built
+setting Z_DEFAULT_COMPRESSION default @Z_DEFAULT_COMPRESSION
+setting Z_DEFAULT_STRATEGY default @Z_FILTERED
+setting Z_DEFAULT_NOFILTER_STRATEGY default @Z_DEFAULT_STRATEGY
+
+setting TEXT_Z_DEFAULT_COMPRESSION default @Z_DEFAULT_COMPRESSION
+setting TEXT_Z_DEFAULT_STRATEGY default @Z_DEFAULT_STRATEGY
+

 # The alternative is to call functions to read PNG values, if
 # the functions are turned *off* the read macros must always
 # be enabled, so turning this off will actually force the
 # The alternative is to call functions to read PNG values, if
 # the functions are turned *off* the read macros must always
 # be enabled, so turning this off will actually force the


@@ -179,10 +256,36 @@ option READ_INT_FUNCTIONS requires READ
 option WRITE_INT_FUNCTIONS disabled
 option WRITE enables WRITE_INT_FUNCTIONS
 
 option WRITE_INT_FUNCTIONS disabled
 option WRITE enables WRITE_INT_FUNCTIONS
 

-# Generic options - affect both read and write.
+# Error controls
+#
+# WARNINGS: normally on, if off no warnings are generated
+# ERROR_TEXT: normally on, if off errors happen but there is no message
+# ERROR_NUMBERS: unimplemented feature, therefore disabled
+# BENIGN_ERRORS: support for just issuing warnings for recoverable errors
+#
+# BENIGN_READ_ERRORS:
+#     By default recoverable errors on read should just generate warnings,
+#     generally safe but PNG files that don't conform to the specification will
+#     be accepted if a meaningful result can be produced.
+#
+# BENIGN_WRITE_ERRORS:
+#     By default recoverable errors on write should just generate warnings,
+#     not generally safe because this allows the application to write invalid
+#     PNG files.  Applications should enable this themselves; it's useful
+#     because it means that a failure to write an ancilliary chunk can often be
+#     ignored.

 
 option WARNINGS
 
 option WARNINGS

+option ERROR_TEXT
+option ERROR_NUMBERS disabled
+

 option BENIGN_ERRORS
 option BENIGN_ERRORS

+option BENIGN_WRITE_ERRORS requires BENIGN_ERRORS disabled
+option BENIGN_READ_ERRORS requires BENIGN_ERRORS
+
+
+# Generic options - affect both read and write.
+

 option MNG_FEATURES
 
 # Arithmetic options, the first is the big switch that chooses between internal
 option MNG_FEATURES
 
 # Arithmetic options, the first is the big switch that chooses between internal


@@ -193,10 +296,6 @@ option FLOATING_ARITHMETIC
 option FLOATING_POINT enables ok_math
 option FIXED_POINT enables ok_math
 
 option FLOATING_POINT enables ok_math
 option FIXED_POINT enables ok_math
 

-# Added at libpng version 1.4.0
-
-option ERROR_TEXT
-

 # The following is always on (defined empty)
 
 setting CALLOC_SUPPORTED default
 # The following is always on (defined empty)
 
 setting CALLOC_SUPPORTED default


@@ -223,10 +322,6 @@ option TIME_RFC1123
 option SETJMP
 = NO_SETJMP SETJMP_NOT_SUPPORTED
 
 option SETJMP
 = NO_SETJMP SETJMP_NOT_SUPPORTED
 

-# For the moment this is disabled (no code support):
-
-option ERROR_NUMBERS disabled
-

 # If this is disabled it is not possible for apps to get the
 # values from the 'info' structure, this effectively removes
 # quite a lot of the READ API.
 # If this is disabled it is not possible for apps to get the
 # values from the 'info' structure, this effectively removes
 # quite a lot of the READ API.


@@ -266,20 +361,22 @@ option SET_USER_LIMITS enables SET_CHUNK_CACHE_LIMIT
 
 option SET_USER_LIMITS enables SET_CHUNK_MALLOC_LIMIT
 
 
 option SET_USER_LIMITS enables SET_CHUNK_MALLOC_LIMIT
 

-# Added at libpng-1.0.16 and 1.2.6.  To accept all valid PNGs no matter
-# how large, set these two limits to 0x7fffffff
-
-setting USER_WIDTH_MAX default 1000000
-setting USER_HEIGHT_MAX default 1000000
-
-# Added at libpng-1.2.43.  To accept all valid PNGs no matter
-# how large, set these two limits to 0.
-
-setting USER_CHUNK_CACHE_MAX default 0
-
-# Added at libpng-1.2.43
-
-setting USER_CHUNK_MALLOC_MAX default 0
+# Libpng limits.
+#
+# If these settings are *not* set libpng will not limit the size of
+# images or the size of data in ancilliary chunks.  This does lead to
+# security issues if PNG files come from untrusted sources.
+setting USER_WIDTH_MAX
+setting USER_HEIGHT_MAX
+setting USER_CHUNK_CACHE_MAX
+setting USER_CHUNK_MALLOC_MAX
+
+# To default all these settings to values that are large but probably
+# safe turn the SAFE_LIMITS option on; this will cause the value in
+# pngpriv.h to be used.  Individual values can also be set, simply set
+# them in pngusr.dfa with '@#define PNG_setting value' lines.
+option SAFE_LIMITS enables USER_LIMITS disabled
+= SAFE_LIMITS SAFE_LIMITS

 
 # All of the following options relate to code capabilities for
 # processing image data before creating a PNG or after reading one.
 
 # All of the following options relate to code capabilities for
 # processing image data before creating a PNG or after reading one.


@@ -288,6 +385,19 @@ setting USER_CHUNK_MALLOC_MAX default 0
 # See the comments above about how to change options and settings.
 
 # READ options
 # See the comments above about how to change options and settings.
 
 # READ options

+#
+# WARNING: in libpng 1.5 maintained configuration compatibility with earlier
+# versions.  In some cases turning off an option turned off other options, in
+# others it was ineffective unless dependent options were also turned off.
+# Libpng 1.6 changes this: in general if you turn off an option that affects
+# APIs it stays off and simply disables APIs that depend on it.
+#
+# As a result if you simply port the libpng 1.5 configuration to libpng 1.6 you
+# will probably see build failures due to missing APIs.  Fixing these failures
+# requires some, perhaps considerable, knowledge of what your libpng using
+# applications are doing, fortunately there is no great reason for you to move
+# to libpng 1.6; the new interfaces in 1.6 will take several years to become
+# popular.

 
 option READ enables READ_INTERLACING
 
 
 option READ enables READ_INTERLACING
 


@@ -296,7 +406,7 @@ option READ enables READ_INTERLACING
 # processing after that has happened.  You need to be sure to enable
 # READ_SCALE_16_TO_8 or READ_STRIP_16_TO_8 when you disable READ_16BIT for
 # this to work properly.  You should disable the other option if you need to
 # processing after that has happened.  You need to be sure to enable
 # READ_SCALE_16_TO_8 or READ_STRIP_16_TO_8 when you disable READ_16BIT for
 # this to work properly.  You should disable the other option if you need to

-# ensure a particular convertion (otherwise the app can chose.)
+# ensure a particular conversion (otherwise the app can chose.)

 
 option READ_16BIT requires READ enables 16BIT
 
 
 option READ_16BIT requires READ enables 16BIT
 


@@ -305,27 +415,42 @@ option READ_QUANTIZE requires READ
 option READ_TRANSFORMS requires READ
 = NO_READ_TRANSFORMS READ_TRANSFORMS_NOT_SUPPORTED
 
 option READ_TRANSFORMS requires READ
 = NO_READ_TRANSFORMS READ_TRANSFORMS_NOT_SUPPORTED
 

-option READ_EXPAND requires READ_TRANSFORMS
-option READ_EXPAND_16 requires READ_TRANSFORMS READ_16BIT enables READ_EXPAND
-option READ_SHIFT requires READ_TRANSFORMS
-option READ_PACK requires READ_TRANSFORMS
+# Read gamma handling.  Gamma processing is a core part of libpng and many of
+# the capabilities are dependent on libpng performing gamma correction.
+#
+# In libpng 1.6 disabling gamma processing (setting PNG_NO_READ_GAMMA)
+# consistently disables those parts of the API that depend on it.  Prior to
+# 1.6.0 this was not true; the results were unpredictable and varied between
+# releases.
+#
+# If you disable gamma processing and your program no longer compiles you need
+# to ask whether you really need the APIs that are missing.  If you do then you
+# almost certainly need the gamma processing.
+#
+# If you handle gamma issues outside libpng then you do not need the libpng
+# gamma processing; and it is an enormous waste of space.  You just need to
+# remove the use of libpng APIs that depend on it.
+option READ_GAMMA requires READ_TRANSFORMS, READ_gAMA
+
+option READ_ALPHA_MODE requires READ_TRANSFORMS, READ_GAMMA
+option READ_BACKGROUND requires READ_TRANSFORMS, READ_STRIP_ALPHA, READ_GAMMA

 option READ_BGR requires READ_TRANSFORMS
 option READ_BGR requires READ_TRANSFORMS

-option READ_SWAP requires READ_TRANSFORMS READ_16BIT
-option READ_PACKSWAP requires READ_TRANSFORMS
-option READ_INVERT requires READ_TRANSFORMS
-option READ_BACKGROUND requires READ_TRANSFORMS enables READ_STRIP_ALPHA
-option READ_STRIP_16_TO_8 requires READ_TRANSFORMS
-option READ_SCALE_16_TO_8 requires READ_TRANSFORMS
+option READ_EXPAND_16 requires READ_TRANSFORMS, READ_16BIT, READ_EXPAND
+option READ_EXPAND requires READ_TRANSFORMS

 option READ_FILLER requires READ_TRANSFORMS
 option READ_FILLER requires READ_TRANSFORMS

-option READ_GAMMA requires READ_TRANSFORMS enables READ_gAMA

 option READ_GRAY_TO_RGB requires READ_TRANSFORMS
 option READ_GRAY_TO_RGB requires READ_TRANSFORMS

-
-option READ_ALPHA_MODE requires READ_TRANSFORMS enables READ_GAMMA
-option READ_SWAP_ALPHA requires READ_TRANSFORMS

 option READ_INVERT_ALPHA requires READ_TRANSFORMS
 option READ_INVERT_ALPHA requires READ_TRANSFORMS

+option READ_INVERT requires READ_TRANSFORMS
+option READ_PACK requires READ_TRANSFORMS
+option READ_PACKSWAP requires READ_TRANSFORMS
+option READ_RGB_TO_GRAY requires READ_TRANSFORMS, READ_GAMMA
+option READ_SCALE_16_TO_8 requires READ_TRANSFORMS
+option READ_SHIFT requires READ_TRANSFORMS
+option READ_STRIP_16_TO_8 requires READ_TRANSFORMS

 option READ_STRIP_ALPHA requires READ_TRANSFORMS
 option READ_STRIP_ALPHA requires READ_TRANSFORMS

+option READ_SWAP_ALPHA requires READ_TRANSFORMS
+option READ_SWAP requires READ_TRANSFORMS, READ_16BIT

 option READ_USER_TRANSFORM requires READ_TRANSFORMS
 option READ_USER_TRANSFORM requires READ_TRANSFORMS

-option READ_RGB_TO_GRAY requires READ_TRANSFORMS

 
 option PROGRESSIVE_READ requires READ
 option SEQUENTIAL_READ requires READ
 
 option PROGRESSIVE_READ requires READ
 option SEQUENTIAL_READ requires READ


@@ -349,11 +474,6 @@ option INCH_CONVERSIONS
 
 option BUILD_GRAYSCALE_PALETTE
 
 
 option BUILD_GRAYSCALE_PALETTE
 

-# IN DEVELOPMENT
-# These are currently experimental features; define them if you want
-
-# NOTHING HERE
-

 # WRITE options
 
 option WRITE
 # WRITE options
 
 option WRITE


@@ -368,7 +488,7 @@ option WRITE_TRANSFORMS requires WRITE
 option WRITE_SHIFT requires WRITE_TRANSFORMS
 option WRITE_PACK requires WRITE_TRANSFORMS
 option WRITE_BGR requires WRITE_TRANSFORMS
 option WRITE_SHIFT requires WRITE_TRANSFORMS
 option WRITE_PACK requires WRITE_TRANSFORMS
 option WRITE_BGR requires WRITE_TRANSFORMS

-option WRITE_SWAP requires WRITE_TRANSFORMS WRITE_16BIT
+option WRITE_SWAP requires WRITE_TRANSFORMS, WRITE_16BIT

 option WRITE_PACKSWAP requires WRITE_TRANSFORMS
 option WRITE_INVERT requires WRITE_TRANSFORMS
 option WRITE_FILLER requires WRITE_TRANSFORMS
 option WRITE_PACKSWAP requires WRITE_TRANSFORMS
 option WRITE_INVERT requires WRITE_TRANSFORMS
 option WRITE_FILLER requires WRITE_TRANSFORMS


@@ -390,8 +510,8 @@ option WRITE_FLUSH requires WRITE
 
 # Note: these can be turned off explicitly if not required by the
 # apps implementing the user transforms
 
 # Note: these can be turned off explicitly if not required by the
 # apps implementing the user transforms

-option USER_TRANSFORM_PTR if READ_USER_TRANSFORM WRITE_USER_TRANSFORM
-option USER_TRANSFORM_INFO if READ_USER_TRANSFORM WRITE_USER_TRANSFORM
+option USER_TRANSFORM_PTR if READ_USER_TRANSFORM, WRITE_USER_TRANSFORM
+option USER_TRANSFORM_INFO if READ_USER_TRANSFORM, WRITE_USER_TRANSFORM

 
 # This enables API to set compression parameters for compressing
 # non-IDAT chunks (zTXt, iTXt, iCCP, and unknown chunks).  This feature
 
 # This enables API to set compression parameters for compressing
 # non-IDAT chunks (zTXt, iTXt, iCCP, and unknown chunks).  This feature


@@ -434,17 +554,65 @@ option WRITE_TEXT requires WRITE_ANCILLARY_CHUNKS enables TEXT
 #   API is implemented, they get recorded in pnglibconf.h, but
 #   can't be changed by the application.
 
 #   API is implemented, they get recorded in pnglibconf.h, but
 #   can't be changed by the application.
 

-# Check the correctness of cHRM chunks
+# Colorspace support (enabled as required); just the support for colorant
+# information.  Gamma support, likewise, is just support for the gamma
+# information, READ_GAMMA is required for gamma transformations (so it
+# is possible to read PNG gamma without enabling all the libpng transform
+# code - do this for applications that do their own gamma processing)
+#
+# As of 1.6.0 COLORSPACE is only useful if the application processes the
+# information; this is because the library does not do any colorspace
+# processing, it just validates the data in the PNG file.

 
 

-option CHECK_cHRM requires cHRM
+option GAMMA disabled
+option COLORSPACE enables GAMMA disabled

 
 

+# When an ICC profile is read, or png_set, it will be checked for a match
+# against known sRGB profiles if the sRGB handling is enabled.  This
+# setting controls how much work is done during the check:
+#
+# 0: Just validate the profile MD5 signature if present, otherwise use
+#    the checks in option 1.
+#
+# 1: Additionally check the length, intent and adler32 checksum of the
+#    actual data.   If enabled this will reject known profiles that have
+#    had the rendering intent in the header changed as well as other edits
+#    done without updating the checksum.  See the discussion below.
+#
+# 2: Additionally checksum all the data using the ethernet CRC32 algorithm.
+#    This makes it more difficult to fake profiles and makes it less likely
+#    to get a false positive on profiles with no signature, but is probably
+#    just a waste of time since all currently approved ICC sRGB profiles have
+#    a secure MD5 signature.
+#
+# The rendering intent.  An ICC profile stores an intended rendering intent,
+# but does not include the value in the signature.  The intent is documented
+# as the intent that should be used when combining two profiles.  The sRGB
+# profile is intended, however, to be used with any of the four defined intents.
+# For this reason the sRGB chunk includes an 'intent' to be used when displaying
+# the image (intent is really a property of the image not the profile.)

 #
 #

+# Unfortunately the iCCP chunk does not.  It may therefore be that some
+# applications modify the intent in profiles (including sRGB profiles) to work
+# round this problem.  Selecting an option other than option '0' will cause such
+# modified profiles to be rejected.
+#
+# Security.  The use of Adler32 and CRC32 checksums does not help significantly
+# with any security issues.  It is relatively easy to produce arbitrary profiles
+# with the required checksums on current computer systems.  Nevertheless
+# security does not seem to be an issue because the only consequence of a false
+# positive is a false assertion that the profile is an sRGB profile.  This might
+# be used to hide data from libpng using applications, but it doesn't seem
+# possible to damage them.
+
+setting sRGB_PROFILE_CHECKS default 2
+

 # Artificially align memory - the code typically aligns to 8 byte
 # boundaries if this is switched on, it's a small waste of space
 # but can help (in theory) on some architectures.  Only affects
 # internal structures.  Added at libpng 1.4.0
 
 # Artificially align memory - the code typically aligns to 8 byte
 # boundaries if this is switched on, it's a small waste of space
 # but can help (in theory) on some architectures.  Only affects
 # internal structures.  Added at libpng 1.4.0
 

-option ALIGN_MEMORY
+option ALIGNED_MEMORY

 
 # Buggy compilers (e.g., gcc 2.7.2.2) need PNG_NO_POINTER_INDEXING
 # See png[wr]util.c, normally this should always be *on*
 
 # Buggy compilers (e.g., gcc 2.7.2.2) need PNG_NO_POINTER_INDEXING
 # See png[wr]util.c, normally this should always be *on*


@@ -507,20 +675,44 @@ setting sCAL_PRECISION default 5
 
 setting ZBUF_SIZE default 8192
 
 
 setting ZBUF_SIZE default 8192
 

+# This is the size of the decompression buffer used when counting or checking
+# the decompressed size of an LZ stream from a compressed ancilliary chunk; the
+# decompressed data is never used so a different size may be optimal.  This size
+# was determined using contrib/libtests/timepng.c with compressed zTXt data
+# around 11MByte in size.  Slight speed improvements (up to about 14% in
+# timepng) can be achieved by very large increases (to 32kbyte) on regular data,
+# but highly compressible data shows only around 2% improvement.   The size is
+# chosen to minimize the effects of DoS attacks based on using very large
+# amounts of highly compressible data.
+
+setting INFLATE_BUF_SIZE default 1024
+
+# This is the maximum amount of IDAT data that the sequential reader will
+# process at one time.  The setting does not affect the size of IDAT chunks
+# read, just the amount read at once.  Neither does it affect the progressive
+# reader, which processes just the amount of data the application gives it.
+# The sequential reader is currently unable to process more than one IDAT at
+# once - it has to read and process each one in turn.  There is no point setting
+# this to a value larger than the IDAT chunks typically encountered (it would
+# just waste memory) but there may be some point in reducing it below the value
+# of ZBUF_SIZE (the size of IDAT chunks written by libpng.)
+
+setting IDAT_READ_SIZE default PNG_ZBUF_SIZE
+

 # Ancillary chunks
 chunk bKGD
 # Ancillary chunks
 chunk bKGD

-chunk cHRM
-chunk gAMA
+chunk cHRM enables COLORSPACE
+chunk gAMA enables GAMMA

 chunk hIST
 chunk hIST

-chunk iCCP
+chunk iCCP enables COLORSPACE, GAMMA

 chunk iTXt
 chunk oFFs
 chunk pCAL
 chunk iTXt
 chunk oFFs
 chunk pCAL

-chunk sCAL

 chunk pHYs
 chunk sBIT
 chunk pHYs
 chunk sBIT

+chunk sCAL

 chunk sPLT
 chunk sPLT

-chunk sRGB
+chunk sRGB enables COLORSPACE, GAMMA

 chunk tEXt requires TEXT
 chunk tIME
 chunk tRNS
 chunk tEXt requires TEXT
 chunk tIME
 chunk tRNS


@@ -532,9 +724,55 @@ chunk zTXt
 
 option READ_OPT_PLTE requires READ_ANCILLARY_CHUNKS
 
 
 option READ_OPT_PLTE requires READ_ANCILLARY_CHUNKS
 

-option READ_UNKNOWN_CHUNKS requires READ
-option READ_UNKNOWN_CHUNKS enables UNKNOWN_CHUNKS READ_USER_CHUNKS
-option READ_USER_CHUNKS requires READ enables USER_CHUNKS
+# Unknown chunk handling
+#
+# 'UNKNOWN_CHUNKS' is a global option to disable all unknown chunk handling on
+# read or write; everything else below requires it (directly or indirectly).
+option UNKNOWN_CHUNKS
+
+# There are three main options to control the ability to read and write unknown
+# chunks.  If either read option is turned on then unknown chunks will be read,
+# otherwise they are skipped.  If the write option is turned on unknown chunks
+# set by png_set_unknown_chunks will be written otherwise it is an error to call
+# that API on a write struct.
+option WRITE_UNKNOWN_CHUNKS requires WRITE requires UNKNOWN_CHUNKS
+option WRITE_UNKNOWN_CHUNKS enables STORE_UNKNOWN_CHUNKS
+
+# The first way to read user chunks is to have libpng save them for a later call
+# to png_get_unknown_chunks, the application must call
+# png_set_keep_unknown_chunks to cause this to actually happen (see png.h)
+option SAVE_UNKNOWN_CHUNKS requires READ requires SET_UNKNOWN_CHUNKS
+option SAVE_UNKNOWN_CHUNKS enables READ_UNKNOWN_CHUNKS, STORE_UNKNOWN_CHUNKS
+
+# The second approach is to use an application provided callback to process the
+# chunks, the callback can either handle the chunk entirely itself or request
+# that libpng store the chunk for later retrieval via png_get_unknown_chunks.
+#
+# Note that there is no 'WRITE_USER_CHUNKS' so the USER_CHUNKS option is always
+# the same as READ_USER_CHUNKS at present
+option READ_USER_CHUNKS requires READ, UNKNOWN_CHUNKS
+option READ_USER_CHUNKS enables READ_UNKNOWN_CHUNKS, USER_CHUNKS
+
+# Two further options are provided to allow detailed control of the handling.
+# The first enables png_set_keep_unknown_chunks; this allows the default to be
+# changed from discarding unknown chunks and allows per-chunk control.  This is
+# required to use the SAVE_UNKNOWN_CHUNKS option.  If enabled this option also
+# applies to write (see png.h), otherwise the write API simply writes all the
+# chunks it is given.
+#
+# The second option extends the unknown handling to allow known chunks to be
+# handled as though they were unknown.  This option doesn't change any APIs, it
+# merely turns on the code to check known as well as unknown chunks.
+#
+# This option no longer affects the write code.  It can be safely disabled and
+# will prevent applications stopping libpng reading known chunks.
+option SET_UNKNOWN_CHUNKS requires UNKNOWN_CHUNKS
+option HANDLE_AS_UNKNOWN requires SET_UNKNOWN_CHUNKS
+
+# The following options are derived from the above and should not be turned on
+# explicitly.
+option READ_UNKNOWN_CHUNKS requires UNKNOWN_CHUNKS disabled
+option STORE_UNKNOWN_CHUNKS requires UNKNOWN_CHUNKS disabled

 
 option CONVERT_tIME requires WRITE_ANCILLARY_CHUNKS
 # The "tm" structure is not supported on WindowsCE
 
 option CONVERT_tIME requires WRITE_ANCILLARY_CHUNKS
 # The "tm" structure is not supported on WindowsCE


@@ -545,13 +783,10 @@ option CONVERT_tIME requires WRITE_ANCILLARY_CHUNKS
 
 option WRITE_FILTER requires WRITE
 
 
 option WRITE_FILTER requires WRITE
 

-option WRITE_UNKNOWN_CHUNKS requires WRITE
-
-option HANDLE_AS_UNKNOWN
-
-option SAVE_INT_32 requires WRITE
-
-# png_save_int_32 is required by the ancillary chunks oFFs and pCAL
+option SAVE_INT_32 disabled
+# png_save_int_32 is required internally for writing the ancillary chunks oFFs
+# and pCAL and for both reading and writing iCCP (for the generation/checking of
+# the corresponding cHRM/gAMA chunks) if full ICC is supported.

 
 # added at libpng-1.5.4
 
 
 # added at libpng-1.5.4
 


@@ -576,3 +811,46 @@ option WRITE_COMPRESSED_TEXT enables WRITE_TEXT
 # leave the row_pointers member out of the info structure.
 
 option INFO_IMAGE
 # leave the row_pointers member out of the info structure.
 
 option INFO_IMAGE

+
+# added at libpng-1.5.10
+# Turn this off to disable warning about invalid palette index and
+# leave the num_palette_max member out of the png structure.
+
+option CHECK_FOR_INVALID_INDEX enables READ_CHECK_FOR_INVALID_INDEX
+option CHECK_FOR_INVALID_INDEX enables WRITE_CHECK_FOR_INVALID_INDEX
+option READ_CHECK_FOR_INVALID_INDEX requires READ, CHECK_FOR_INVALID_INDEX
+option WRITE_CHECK_FOR_INVALID_INDEX requires WRITE, CHECK_FOR_INVALID_INDEX
+
+# added at libpng-1.5.15
+option GET_PALETTE_MAX enables READ_GET_PALETTE_MAX WRITE_GET_PALETTE_MAX
+option READ_GET_PALETTE_MAX requires READ_CHECK_FOR_INVALID_INDEX disabled
+option WRITE_GET_PALETTE_MAX requires WRITE_CHECK_FOR_INVALID_INDEX disabled
+
+# Simplified API options (added at libpng-1.6.0)
+# Read:
+option SIMPLIFIED_READ,
+   requires SEQUENTIAL_READ READ_TRANSFORMS, SETJMP, BENIGN_ERRORS READ_GAMMA,
+   enables READ_EXPAND, READ_16BIT READ_EXPAND_16, READ_SCALE_16_TO_8,
+      READ_RGB_TO_GRAY, READ_ALPHA_MODE READ_BACKGROUND READ_STRIP_ALPHA,
+      READ_FILLER, READ_SWAP
+
+option SIMPLIFIED_READ_AFIRST requires SIMPLIFIED_READ disabled
+option READ_SWAP_ALPHA enables SIMPLIFIED_READ_AFIRST
+
+option SIMPLIFIED_READ_BGR requires SIMPLIFIED_READ disabled
+option READ_BGR enables SIMPLIFIED_READ_BGR
+
+# Write:
+option SIMPLIFIED_WRITE,
+   requires WRITE STDIO, SETJMP,
+   enables WRITE_SWAP WRITE_gAMA, WRITE_sRGB WRITE_cHRM
+
+option SIMPLIFIED_WRITE_AFIRST requires SIMPLIFIED_WRITE disabled
+option WRITE_SWAP_ALPHA enables SIMPLIFIED_WRITE_AFIRST
+
+option SIMPLIFIED_WRITE_BGR requires SIMPLIFIED_WRITE disabled
+option WRITE_BGR enables SIMPLIFIED_WRITE_BGR
+
+# Formats:
+option FORMAT_AFIRST if SIMPLIFIED_READ_AFIRST, SIMPLIFIED_WRITE_AFIRST
+option FORMAT_BGR if SIMPLIFIED_READ_BGR, SIMPLIFIED_WRITE_BGR