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Diffstat (limited to 'libpng/scripts/options.awk')
| -rwxr-xr-x | libpng/scripts/options.awk | 898 |
1 files changed, 898 insertions, 0 deletions
diff --git a/libpng/scripts/options.awk b/libpng/scripts/options.awk new file mode 100755 index 00000000..81b82ff0 --- /dev/null +++ b/libpng/scripts/options.awk @@ -0,0 +1,898 @@ +#!/bin/awk -f +# scripts/options.awk - library build configuration control +# +# last changed in libpng version 1.6.11 - June 5, 2014 +# +# Copyright (c) 1998-2014 Glenn Randers-Pehrson +# +# This code is released under the libpng license. +# For conditions of distribution and use, see the disclaimer +# and license in png.h + +# The output of this script is written to the file given by +# the variable 'out'. The script is run twice, once with +# an intermediate output file, 'options.tmp' then again on +# that file to produce the final output: +# +# awk -f scripts/options.awk out=options.tmp scripts/options.dfa 1>&2 +# awk -f scripts/options.awk out=options.dfn options.tmp 1>&2 +# +# Some options may be specified on the command line: +# +# deb=1 Causes debugging to be output +# logunsupported=1 Causes all options to be recorded in the output +# everything=off Causes all options to be disabled by default +# everything=on Causes all options to be enabled by default +# +# If awk fails on your platform, try nawk instead. +# +# These options may also be specified in the original input file (and +# are copied to the preprocessed file). + +BEGIN{ + out="" # intermediate, preprocessed, file + pre=-1 # preprocess (first line) + version="libpng version unknown" # version information + version_file="" # where to find the version + err=0 # in-line exit sets this + # The following definitions prevent the C preprocessor noticing the lines + # that will be in the final output file. Some C preprocessors tokenise + # the lines, for example by inserting spaces around operators, and all + # C preprocessors notice lines that start with '#', most remove comments. + # The technique adopted here is to make the final output lines into + # C strings (enclosed in double quotes), preceeded by PNG_DFN. As a + # consequence the output cannot contain a 'raw' double quote - instead put + # @' in, this will be replaced by a single " afterward. See the parser + # script dfn.awk for more capabilities (not required here). Note that if + # you need a " in a 'setting' in pnglibconf.dfa it must also be @'! + dq="@'" # For a single double quote + start=" PNG_DFN \"" # Start stuff to output (can't contain a "!) + end="\" " # End stuff to output + subs="@\" " # Substitute start (substitute a C macro) + sube=" \"@" # Substitute end + comment=start "/*" # Comment start + cend="*/" end # Comment end + def=start "#define PNG_" # Arbitrary define + sup="_SUPPORTED" end # end supported option + und=comment "#undef PNG_" # Unsupported option + une="_SUPPORTED" cend # end unsupported option + error=start "ERROR:" # error message, terminate with 'end' + + # Variables + deb=0 # debug - set on command line + everything="" # do not override defaults + logunsupported=0 # write unsupported options too + + # Precreate arrays + # for each option: + option[""] = "" # list of all options: default enabled/disabled + done[""] = 1 # marks option as having been output + requires[""] = "" # requires by option + iffs[""] = "" # if by option + enabledby[""] = "" # options that enable it by option + sets[""] = "" # settings set by each option + setval[""] = "" # value to set (indexed: 'option sets[option]') + # for each setting: + setting[""] = "" # requires by setting + defaults[""] = "" # used for a defaulted value + doneset[""] = 1 # marks setting as having been output + r[""] = "" # Temporary array + + # For decorating the output file + protect = "" +} + +# The output file must be specified before any input: +out == "" { + print "out=output.file must be given on the command line" + err = 1 + exit 1 +} + +# The very first line indicates whether we are reading pre-processed +# input or not, this must come *first* because 'PREPROCESSED' needs +# to be the very first line in the temporary file. +pre == -1{ + if ($0 == "PREPROCESSED") { + pre = 0 + next + } else { + pre = 1 + print "PREPROCESSED" >out + # And fall through to continue processing + } +} + +# While pre-processing if version is set to "search" look for a version string +# in the following file. +pre && version == "search" && version_file == ""{ + version_file = FILENAME +} + +pre && version == "search" && version_file != FILENAME{ + print "version string not found in", version_file + err = 1 + exit 1 +} + +pre && version == "search" && $0 ~ /^ \* libpng version/{ + version = substr($0, 4) + print "version =", version >out + next +} + +pre && FILENAME == version_file{ + next +} + +# variable=value +# Sets the given variable to the given value (the syntax is fairly +# free form, except for deb (you are expected to understand how to +# set the debug variable...) +# +# This happens before the check on 'pre' below skips most of the +# rest of the actions, so the variable settings happen during +# preprocessing but are recorded in the END action too. This +# allows them to be set on the command line too. +$0 ~ /^[ ]*version[ ]*=/{ + sub(/^[ ]*version[ ]*=[ ]*/, "") + version = $0 + next +} +$0 ~ /^[ ]*everything[ =]*off[ ]*$/{ + everything = "off" + next +} +$0 ~ /^[ ]*everything[ =]*on[ ]*$/{ + everything = "on" + next +} +$0 ~ /^[ ]*logunsupported[ =]*0[ ]*$/{ + logunsupported = 0 + next +} +$0 ~ /^[ ]*logunsupported[ =]*1[ ]*$/{ + logunsupported = 1 + next +} +$1 == "deb" && $2 == "=" && NF == 3{ + deb = $3 + next +} + +# Preprocessing - this just copies the input file with lines +# that need preprocessing (just chunk at present) expanded +# The bare "pre" instead of "pre != 0" crashes under Sunos awk +pre && $1 != "chunk"{ + print >out + next +} + +# The first characters of the line determine how it is processed, +# leading spaces are ignored. In general tokens that are not +# keywords are the names of options. An option 'name' is +# controlled by the definition of the corresponding macros: +# +# PNG_name_SUPPORTED The option is turned on +# PNG_NO_name +# PNG_NO_name_SUPPORTED If the first macro is not defined +# either of these will turn the option off +# +# If none of these macros are defined the option is turned on, unless +# the keyword 'off' is given in a line relating to the option. The +# keyword 'on' can also be given, but it will be ignored (since it is +# the default.) +# +# In the syntax below a 'name' is indicated by "NAME", other macro +# values are indicated by "MACRO", as with "NAME" the leading "PNG_" +# is omitted, but in this case the "NO_" prefix and the "_SUPPORTED" +# suffix are never used. +# +# Each line is introduced by a keyword - the first non-space characters +# on the line. A line starting with a '#' is a comment - it is totally +# ignored. Keywords are as follows, a NAME, is simply a macro name +# without the leading PNG_, PNG_NO_ or the trailing _SUPPORTED. + +$1 ~ /^#/ || $0 ~ /^[ ]*$/{ + next +} + +# com <comment> +# The whole line is placed in the output file as a comment with +# the preceding 'com' removed +$1 == "com"{ + if (NF > 1) { + # sub(/^[ ]*com[ ]*/, "") + $1 = "" + print comment $0, cend >out + } else + print start end >out + next +} + +# version +# Inserts a version comment +$1 == "version" && NF == 1{ + if (version == "") { + print "ERROR: no version string set" + err = 1 # prevent END{} running + exit 1 + } + + print comment, version, cend >out + next +} + +# file output input protect +# Informational: the official name of the input file (without +# make generated local directories), the official name of the +# output file and, if required, a name to use in a protection +# macro for the contents. +$1 == "file" && NF >= 2{ + print comment, $2, cend >out + print comment, "Machine generated file: DO NOT EDIT", cend >out + if (NF >= 3) + print comment, "Derived from:", $3, cend >out + protect = $4 + if (protect != "") { + print start "#ifndef", protect end >out + print start "#define", protect end >out + } + next +} + +# option NAME ( (requires|enables|if) NAME* | on | off | disabled | +# sets SETTING VALUE+ )* +# +# Declares an option 'NAME' and describes its default setting (disabled) +# and its relationship to other options. The option is disabled +# unless *all* the options listed after 'requires' are set and at +# least one of the options listed after 'if' is set. If the +# option is set then it turns on all the options listed after 'enables'. +# +# Note that "enables" takes priority over the required/if/disabled/off +# setting of the target option. +# +# The definition file may list an option as 'disabled': off by default, +# otherwise the option is enabled: on by default. A later (and it must +# be later) entry may turn an option on or off explicitly. + +$1 == "option" && NF >= 2{ + opt = $2 + sub(/,$/,"",opt) + onoff = option[opt] # records current (and the default is "", enabled) + key = "" + istart = 3 + do { + if (istart == 1) { # continuation line + val = getline + + if (val != 1) { # error reading it + if (val == 0) + print "option", opt ": ERROR: missing continuation line" + else + print "option", opt ": ERROR: error reading continuation line" + + # This is a hard error + err = 1 # prevent END{} running + exit 1 + } + } + + for (i=istart; i<=NF; ++i) { + val=$(i) + sub(/,$/,"",val) + if (val == "on" || val == "off" || val == "disabled" || val =="enabled") { + key = "" + if (onoff != val) { + # on or off can zap disabled or enabled: + if (onoff == "" || (onoff == "disabled" || onoff == "enabled") && + (val == "on" || val == "off")) { + # It's easy to mis-spell the option when turning it + # on or off, so warn about it here: + if (onoff == "" && (val == "on" || val == "off")) { + print "option", opt ": ERROR: turning unrecognized option", val + # For the moment error out - it is safer + err = 1 # prevent END{} running + exit 1 + } + onoff = val + } else { + # Print a message, otherwise the error + # below is incomprehensible + print "option", opt ": currently", onoff ": attempt to turn", val + break + } + } + } else if (val == "requires" || val == "if" || val == "enables" || val =="sets") { + key = val + } else if (key == "requires") { + requires[opt] = requires[opt] " " val + } else if (key == "if") { + iffs[opt] = iffs[opt] " " val + } else if (key == "enables") { + enabledby[val] = enabledby[val] " " opt + } else if (key == "sets") { + sets[opt] = sets[opt] " " val + key = "setval" + set = val + } else if (key == "setval") { + setval[opt " " set] = setval[opt " " set] " " val + } else + break # bad line format + } + + istart = 1 + } while (i > NF && $0 ~ /,$/) + + if (i > NF) { + # Set the option, defaulting to 'enabled' + if (onoff == "") onoff = "enabled" + option[opt] = onoff + next + } + # Else fall through to the error handler +} + +# chunk NAME [requires OPT] [enables LIST] [on|off|disabled] +# Expands to the 'option' settings appropriate to the reading and +# writing of an ancilliary PNG chunk 'NAME': +# +# option READ_NAME requires READ_ANCILLARY_CHUNKS [READ_OPT] +# option READ_NAME enables NAME LIST +# [option READ_NAME off] +# option WRITE_NAME requires WRITE_ANCILLARY_CHUNKS [WRITE_OPT] +# option WRITE_NAME enables NAME LIST +# [option WRITE_NAME off] + +pre != 0 && $1 == "chunk" && NF >= 2{ + # 'chunk' is handled on the first pass by writing appropriate + # 'option' lines into the intermediate file. + opt = $2 + sub(/,$/,"",opt) + onoff = "" + reqread = "" + reqwrite = "" + enables = "" + req = 0 + istart = 3 + do { + if (istart == 1) { # continuation line + val = getline + + if (val != 1) { # error reading it + if (val == 0) + print "chunk", opt ": ERROR: missing continuation line" + else + print "chunk", opt ": ERROR: error reading continuation line" + + # This is a hard error + err = 1 # prevent END{} running + exit 1 + } + } + + # read the keywords/additional OPTS + for (i=istart; i<=NF; ++i) { + val = $(i) + sub(/,$/,"",val) + if (val == "on" || val == "off" || val == "disabled") { + if (onoff != val) { + if (onoff == "") + onoff = val + else + break # on/off conflict + } + req = 0 + } else if (val == "requires") + req = 1 + else if (val == "enables") + req = 2 + else if (req == 1){ + reqread = reqread " READ_" val + reqwrite = reqwrite " WRITE_" val + } else if (req == 2) + enables = enables " " val + else + break # bad line: handled below + } + + istart = 1 + } while (i > NF && $0 ~ /,$/) + + if (i > NF) { + # Output new 'option' lines to the intermediate file (out) + print "option READ_" opt, "requires READ_ANCILLARY_CHUNKS" reqread, "enables", opt enables , onoff >out + print "option WRITE_" opt, "requires WRITE_ANCILLARY_CHUNKS" reqwrite, "enables", opt enables, onoff >out + next + } + # Else hit the error handler below - bad line format! +} + +# setting MACRO ( requires MACRO* )* [ default VALUE ] +# Behaves in a similar way to 'option' without looking for NO_ or +# _SUPPORTED; the macro is enabled if it is defined so long as all +# the 'requires' macros are also defined. The definitions may be +# empty, an error will be issued if the 'requires' macros are +# *not* defined. If given the 'default' value is used if the +# macro is not defined. The default value will be re-tokenised. +# (BTW: this is somewhat restrictive, it mainly exists for the +# support of non-standard configurations and numeric parameters, +# see the uses in scripts/options.dat + +$1 == "setting" && (NF == 2 || NF >= 3 && ($3 == "requires" || $3 == "default")){ + reqs = "" + deflt = "" + isdef = 0 + key = "" + for (i=3; i<=NF; ++i) + if ($(i) == "requires" || $(i) == "default") { + key = $(i) + if (key == "default") isdef = 1 + } else if (key == "requires") + reqs = reqs " " $(i) + else if (key == "default") + deflt = deflt " " $(i) + else + break # Format error, handled below + + setting[$2] = reqs + # NOTE: this overwrites a previous value silently + if (isdef && deflt == "") + deflt = " " # as a flag to force output + defaults[$2] = deflt + next +} + +# The order of the dependency lines (option, chunk, setting) is irrelevant +# - the 'enables', 'requires' and 'if' settings will be used to determine +# the correct order in the output and the final values in pnglibconf.h are +# not order dependent. 'requires' and 'if' entries take precedence over +# 'enables' from other options; if an option requires another option it +# won't be set regardless of any options that enable it unless the other +# option is also enabled. +# +# Similarly 'enables' trumps a NO_ definition in CFLAGS or pngusr.h +# +# For simplicity cycles in the definitions are regarded as errors, +# even if they are not ambiguous. +# A given NAME can be specified in as many 'option' lines as required, the +# definitions are additive. + +# For backwards compatibility equivalent macros may be listed thus: +# +# = [NO_]NAME MACRO +# Makes -DMACRO equivalent to -DPNG_NO_NAME or -DPNG_NAME_SUPPORTED +# as appropriate. +# +# The definition is injected into the C compiler input when encountered +# in the second pass (so all these definitions appear *after* the @ +# lines!) +# +# 'NAME' is as above, but 'MACRO' is the full text of the equivalent +# old, deprecated, macro. + +$1 == "=" && NF == 3{ + print "#ifdef PNG_" $3 >out + if ($2 ~ /^NO_/) + print "# define PNG_" $2 >out + else + print "# define PNG_" $2 "_SUPPORTED" >out + print "#endif" >out + next +} + +# Lines may be injected into the C compiler input by preceding them +# with an "@" character. The line is copied with just the leading +# @ removed. + +$1 ~ /^@/{ + # sub(/^[ ]*@/, "") + $1 = substr($1, 2) + print >out + next +} + +# Check for unrecognized lines, because of the preprocessing chunk +# format errors will be detected on the first pass independent of +# any other format errors. +{ + print "options.awk: bad line (" NR "):", $0 + err = 1 # prevent END{} running + exit 1 +} + +# For checking purposes names that start with "ok_" or "fail_" are +# not output to pnglibconf.h and must be either enabled or disabled +# respectively for the build to succeed. This allows interdependencies +# between options of the form "at least one of" or "at most one of" +# to be checked. For example: +# +# option FLOATING_POINT enables ok_math +# option FIXED_POINT enables ok_math +# This ensures that at least one of FLOATING_POINT and FIXED_POINT +# must be set for the build to succeed. +# +# option fail_math requires FLOATING_POINT FIXED_POINT +# This means the build will fail if *both* FLOATING_POINT and +# FIXED_POINT are set (this is an example; in fact both are allowed.) +# +# If all these options were given the build would require exactly one +# of the names to be enabled. + +END{ + # END{} gets run on an exit (a traditional awk feature) + if (err) exit 1 + + if (pre) { + # Record the final value of the variables + print "deb =", deb >out + if (everything != "") { + print "everything =", everything >out + } + print "logunsupported =", logunsupported >out + exit 0 + } + + # Do the options first (allowing options to set settings). The dependency + # tree is thus: + # + # name > name + # name requires name + # name if name + # name enabledby name + # + # First build a list 'tree' by option of all the things on which + # it depends. + print "" >out + print "/* OPTIONS */" >out + print comment, "options", cend >out + for (opt in enabledby) tree[opt] = 1 # may not be explicit options + for (opt in option) if (opt != "") { + o = option[opt] + # option should always be one of the following values + if (o != "on" && o != "off" && o != "disabled" && o != "enabled") { + print "internal option error (" o ")" + exit 1 + } + tree[opt] = "" # so unlisted options marked + } + for (opt in tree) if (opt != "") { + if (tree[opt] == 1) { + tree[opt] = "" + if (option[opt] != "") { + print "internal error (1)" + exit 1 + } + # Macros only listed in 'enables' remain off unless + # one of the enabling macros is on. + option[opt] = "disabled" + } + + split("", list) # clear 'list' + # Now add every requires, iffs or enabledby entry to 'list' + # so that we can add a unique list of requirements to tree[i] + split(requires[opt] iffs[opt] enabledby[opt], r) + for (i in r) list[r[i]] = 1 + for (i in list) tree[opt] = tree[opt] " " i + } + + # print the tree for extreme debugging + if (deb > 2) for (i in tree) if (i != "") print i, "depends-on" tree[i] + + # Ok, now check all options marked explicitly 'on' or 'off': + # + # If an option[opt] is 'on' then turn on all requires[opt] + # If an option[opt] is 'off' then turn off all enabledby[opt] + # + # Error out if we have to turn 'on' to an 'off' option or vice versa. + npending = 0 + for (opt in option) if (opt != "") { + if (option[opt] == "on" || option[opt] == "off") { + pending[++npending] = opt + } + } + + err = 0 # set on error + while (npending > 0) { + opt = pending[npending--] + if (option[opt] == "on") { + nreqs = split(requires[opt], r) + for (j=1; j<=nreqs; ++j) { + if (option[r[j]] == "off") { + print "option", opt, "turned on, but requirement", r[j], "is turned off" + err = 1 + } else if (option[r[j]] != "on") { + option[r[j]] = "on" + pending[++npending] = r[j] + } + } + } else { + if (option[opt] != "off") { + print "internal error (2)" + exit 1 + } + nreqs = split(enabledby[opt], r) + for (j=1; j<=nreqs; ++j) { + if (option[r[j]] == "on") { + print "option", opt, "turned off, but enabled by", r[j], "which is turned on" + err = 1 + } else if (option[r[j]] != "off") { + option[r[j]] = "off" + pending[++npending] = r[j] + } + } + } + } + if (err) exit 1 + + # Sort options: + print "PNG_DFN_START_SORT 2" >out + + # option[i] is now the complete list of all the tokens we may + # need to output, go through it as above, depth first. + finished = 0 + while (!finished) { + finished = 1 + movement = 0 # done nothing + for (i in option) if (!done[i]) { + nreqs = split(tree[i], r) + if (nreqs > 0) { + for (j=1; j<=nreqs; ++j) if (!done[r[j]]) { + break + } + if (j<=nreqs) { + finished = 0 + continue # next option + } + } + + # All the requirements have been processed, output + # this option. An option is _SUPPORTED if: + # + # all 'requires' are _SUPPORTED AND + # at least one of the 'if' options are _SUPPORTED AND + # EITHER: + # The name is _SUPPORTED (on the command line) + # OR: + # an 'enabledby' is _SUPPORTED + # OR: + # NO_name is not defined AND + # the option is not disabled; an option is disabled if: + # option == off + # option == disabled && everything != on + # option == "" && everything == off + if (deb) print "option", i + print "" >out + print "/* option:", i, option[i] >out + print " * requires: " requires[i] >out + print " * if: " iffs[i] >out + print " * enabled-by:" enabledby[i] >out + print " * sets: " sets[i], "*/" >out + print "#undef PNG_on" >out + print "#define PNG_on 1" >out + + # requires + nreqs = split(requires[i], r) + for (j=1; j<=nreqs; ++j) { + print "#ifndef PNG_" r[j] "_SUPPORTED" >out + print "# undef PNG_on /*!" r[j] "*/" >out + # This error appears in the final output if something + # was switched 'on' but the processing above to force + # the requires did not work + if (option[i] == "on") { + print error, i, "requires", r[j] end >out + } + print "#endif" >out + } + + # if + have_ifs = 0 + nreqs = split(iffs[i], r) + print "#undef PNG_no_if" >out + if (nreqs > 0) { + have_ifs = 1 + print "/* if" iffs[i], "*/" >out + print "#define PNG_no_if 1" >out + for (j=1; j<=nreqs; ++j) { + print "#ifdef PNG_" r[j] "_SUPPORTED" >out + print "# undef PNG_no_if /*" r[j] "*/" >out + print "#endif" >out + } + print "#ifdef PNG_no_if /*missing if*/" >out + print "# undef PNG_on" >out + # There is no checking above for this, because we + # don't know which 'if' to choose, so whine about + # it here: + if (option[i] == "on") { + print error, i, "needs one of:", iffs[i] end >out + } + print "#endif" >out + } + + print "#ifdef PNG_on /*requires, if*/" >out + # enables + print "# undef PNG_not_enabled" >out + print "# define PNG_not_enabled 1" >out + print " /* enabled by" enabledby[i], "*/" >out + nreqs = split(enabledby[i], r) + for (j=1; j<=nreqs; ++j) { + print "#ifdef PNG_" r[j] "_SUPPORTED" >out + print "# undef PNG_not_enabled /*" r[j] "*/" >out + # Oops, probably not intended (should be factored + # out by the checks above). + if (option[i] == "off") { + print error, i, "enabled by:", r[j] end >out + } + print "#endif" >out + } + + print "# ifndef PNG_" i "_SUPPORTED /*!command line*/" >out + print "# ifdef PNG_not_enabled /*!enabled*/" >out + # 'have_ifs' here means that everything = "off" still allows an 'if' on + # an otherwise enabled option to turn it on; otherwise the 'if' + # handling is effectively disabled by 'everything = off' + if (option[i] == "off" || option[i] == "disabled" && everything != "on" || option[i] == "enabled" && everything == "off" && !have_ifs) { + print "# undef PNG_on /*default off*/" >out + } else { + print "# ifdef PNG_NO_" i >out + print "# undef PNG_on /*turned off*/" >out + print "# endif" >out + print "# ifdef PNG_NO_" i "_SUPPORTED" >out + print "# undef PNG_on /*turned off*/" >out + print "# endif" >out + } + print "# endif /*!enabled*/" >out + print "# ifdef PNG_on" >out + # The _SUPPORTED macro must be defined so that dependent + # options output later work. + print "# define PNG_" i "_SUPPORTED" >out + print "# endif" >out + print "# endif /*!command line*/" >out + # If PNG_on is still set the option should be defined in + # pnglibconf.h + print "# ifdef PNG_on" >out + if (i ~ /^fail_/) { + print error, i, "is on: enabled by:" iffs[i] enabledby[i] ", requires" requires[i] end >out + } else if (i !~ /^ok_/) { + print def i sup >out + # Supported option, set required settings + nreqs = split(sets[i], r) + for (j=1; j<=nreqs; ++j) { + print "# ifdef PNG_set_" r[j] >out + # Some other option has already set a value: + print error, i, "sets", r[j] ": duplicate setting" end >out + print error, " previous value: " end "PNG_set_" r[j] >out + print "# else" >out + # Else set the default: note that this won't accept arbitrary + # values, the setval string must be acceptable to all the C + # compilers we use. That means it must be VERY simple; a number, + # a name or a string. + print "# define PNG_set_" r[j], setval[i " " r[j]] >out + print "# endif" >out + } + } + print "# endif /* definition */" >out + print "#endif /*requires, if*/" >out + if (logunsupported || i ~ /^ok_/) { + print "#ifndef PNG_on" >out + if (logunsupported) { + print und i une >out + } + if (i ~ /^ok_/) { + print error, i, "not enabled: requires:" requires[i] ", enabled by:" iffs[i] enabledby[i] end >out + } + print "#endif" >out + } + + done[i] = 1 + ++movement + } + + if (!finished && !movement) { + print "option: loop or missing option in dependency tree, cannot process:" + for (i in option) if (!done[i]) { + print " option", i, "depends on" tree[i], "needs:" + nreqs = split(tree[i], r) + if (nreqs > 0) for (j=1; j<=nreqs; ++j) if (!done[r[j]]) { + print " " r[j] + } + } + exit 1 + } + } + print "PNG_DFN_END_SORT" >out + print comment, "end of options", cend >out + + # Do the 'setting' values second, the algorithm the standard + # tree walk (O(1)) done in an O(2) while/for loop; interations + # settings x depth, outputing the deepest required macros + # first. + print "" >out + print "/* SETTINGS */" >out + print comment, "settings", cend >out + # Sort (in dfn.awk) on field 2, the setting name + print "PNG_DFN_START_SORT 2" >out + finished = 0 + while (!finished) { + finished = 1 + movement = 0 # done nothing + for (i in setting) if (!doneset[i]) { + nreqs = split(setting[i], r) + if (nreqs > 0) { + # By default assume the requires values are options, but if there + # is no option with that name check for a setting + for (j=1; j<=nreqs; ++j) if (option[r[j]] == "" && !doneset[r[j]]) { + break + } + if (j<=nreqs) { + finished = 0 + continue # try a different setting + } + } + + # All the requirements have been processed, output + # this setting. + if (deb) print "setting", i + deflt = defaults[i] + # Remove any spurious trailing spaces + sub(/ *$/,"",deflt) + # A leading @ means leave it unquoted so the preprocessor + # can substitute the build time value + if (deflt ~ /^ @/) + deflt = " " subs substr(deflt, 3) sube + print "" >out + print "/* setting: ", i >out + print " * requires:" setting[i] >out + print " * default: ", defaults[i] deflt, "*/" >out + for (j=1; j<=nreqs; ++j) { + if (option[r[j]] != "") + print "#ifndef PNG_" r[j] "_SUPPORTED" >out + else + print "#ifndef PNG_" r[j] >out + print error, i, "requires", r[j] end >out + print "# endif" >out + } + # The precedence is: + # + # 1) External definition; trumps: + # 2) Option 'sets' value; trumps: + # 3) Setting 'default' + # + print "#ifdef PNG_" i >out + # PNG_<i> is defined, so substitute the value: + print def i, subs "PNG_" i sube end >out + print "#else /* use default */" >out + print "# ifdef PNG_set_" i >out + # Value from an option 'sets' argument + print def i, subs "PNG_set_" i sube end >out + # This is so that subsequent tests on the setting work: + print "# define PNG_" i, "1" >out + if (defaults[i] != "") { + print "# else /*default*/" >out + print def i deflt end >out + print "# define PNG_" i, "1" >out + } + print "# endif /* defaults */" >out + print "#endif /* setting", i, "*/" >out + + doneset[i] = 1 + ++movement + } + + if (!finished && !movement) { + print "setting: loop or missing setting in 'requires', cannot process:" + for (i in setting) if (!doneset[i]) { + print " setting", i, "requires" setting[i] + } + exit 1 + } + } + print "PNG_DFN_END_SORT" >out + print comment, "end of settings", cend >out + + # Regular end - everything looks ok + if (protect != "") { + print start "#endif", "/*", protect, "*/" end >out + } +} |