kernel-doc

#!/usr/bin/env perl

use warnings;
use strict;

## Copyright (c) 1998 Michael Zucchi, All Rights Reserved        ##
## Copyright (C) 2000, 1  Tim Waugh <twaugh@redhat.com>          ##
## Copyright (C) 2001  Simon Huggins                             ##
## Copyright (C) 2005-2012  Randy Dunlap                         ##
## Copyright (C) 2012  Dan Luedtke                               ##
## 								 ##
## #define enhancements by Armin Kuster <akuster@mvista.com>	 ##
## Copyright (c) 2000 MontaVista Software, Inc.			 ##
## 								 ##
## This software falls under the GNU General Public License.     ##
## Please read the COPYING file for more information             ##

# 18/01/2001 - 	Cleanups
# 		Functions prototyped as foo(void) same as foo()
# 		Stop eval'ing where we don't need to.
# -- huggie@earth.li

# 27/06/2001 -  Allowed whitespace after initial "/**" and
#               allowed comments before function declarations.
# -- Christian Kreibich <ck@whoop.org>

# Still to do:
# 	- add perldoc documentation
# 	- Look more closely at some of the scarier bits :)

# 26/05/2001 - 	Support for separate source and object trees.
#		Return error code.
# 		Keith Owens <kaos@ocs.com.au>

# 23/09/2001 - Added support for typedefs, structs, enums and unions
#              Support for Context section; can be terminated using empty line
#              Small fixes (like spaces vs. \s in regex)
# -- Tim Jansen <tim@tjansen.de>

# 25/07/2012 - Added support for HTML5
# -- Dan Luedtke <mail@danrl.de>

sub usage {
    my $message = <<"EOF";
Usage: $0 [OPTION ...] FILE ...

Read C language source or header FILEs, extract embedded documentation comments,
and print formatted documentation to standard output.

The documentation comments are identified by "/**" opening comment mark. See
Documentation/doc-guide/kernel-doc.rst for the documentation comment syntax.

Output format selection (mutually exclusive):
  -man			Output troff manual page format. This is the default.
  -rst			Output reStructuredText format.
  -none			Do not output documentation, only warnings.

Output selection (mutually exclusive):
  -export		Only output documentation for symbols that have been
			exported using EXPORT_SYMBOL() or EXPORT_SYMBOL_GPL()
                        in any input FILE or -export-file FILE.
  -internal		Only output documentation for symbols that have NOT been
			exported using EXPORT_SYMBOL() or EXPORT_SYMBOL_GPL()
                        in any input FILE or -export-file FILE.
  -function NAME	Only output documentation for the given function(s)
			or DOC: section title(s). All other functions and DOC:
			sections are ignored. May be specified multiple times.
  -nofunction NAME	Do NOT output documentation for the given function(s);
			only output documentation for the other functions and
			DOC: sections. May be specified multiple times.

Output selection modifiers:
  -no-doc-sections	Do not output DOC: sections.
  -enable-lineno        Enable output of #define LINENO lines. Only works with
                        reStructuredText format.
  -export-file FILE     Specify an additional FILE in which to look for
                        EXPORT_SYMBOL() and EXPORT_SYMBOL_GPL(). To be used with
                        -export or -internal. May be specified multiple times.

Other parameters:
  -v			Verbose output, more warnings and other information.
  -h			Print this help.

EOF
    print $message;
    exit 1;
}

#
# format of comments.
# In the following table, (...)? signifies optional structure.
#                         (...)* signifies 0 or more structure elements
# /**
#  * function_name(:)? (- short description)?
# (* @parameterx: (description of parameter x)?)*
# (* a blank line)?
#  * (Description:)? (Description of function)?
#  * (section header: (section description)? )*
#  (*)?*/
#
# So .. the trivial example would be:
#
# /**
#  * my_function
#  */
#
# If the Description: header tag is omitted, then there must be a blank line
# after the last parameter specification.
# e.g.
# /**
#  * my_function - does my stuff
#  * @my_arg: its mine damnit
#  *
#  * Does my stuff explained.
#  */
#
#  or, could also use:
# /**
#  * my_function - does my stuff
#  * @my_arg: its mine damnit
#  * Description: Does my stuff explained.
#  */
# etc.
#
# Besides functions you can also write documentation for structs, unions,
# enums and typedefs. Instead of the function name you must write the name
# of the declaration;  the struct/union/enum/typedef must always precede
# the name. Nesting of declarations is not supported.
# Use the argument mechanism to document members or constants.
# e.g.
# /**
#  * struct my_struct - short description
#  * @a: first member
#  * @b: second member
#  *
#  * Longer description
#  */
# struct my_struct {
#     int a;
#     int b;
# /* private: */
#     int c;
# };
#
# All descriptions can be multiline, except the short function description.
#
# For really longs structs, you can also describe arguments inside the
# body of the struct.
# eg.
# /**
#  * struct my_struct - short description
#  * @a: first member
#  * @b: second member
#  *
#  * Longer description
#  */
# struct my_struct {
#     int a;
#     int b;
#     /**
#      * @c: This is longer description of C
#      *
#      * You can use paragraphs to describe arguments
#      * using this method.
#      */
#     int c;
# };
#
# This should be use only for struct/enum members.
#
# You can also add additional sections. When documenting kernel functions you
# should document the "Context:" of the function, e.g. whether the functions
# can be called form interrupts. Unlike other sections you can end it with an
# empty line.
# A non-void function should have a "Return:" section describing the return
# value(s).
# Example-sections should contain the string EXAMPLE so that they are marked
# appropriately in DocBook.
#
# Example:
# /**
#  * user_function - function that can only be called in user context
#  * @a: some argument
#  * Context: !in_interrupt()
#  *
#  * Some description
#  * Example:
#  *    user_function(22);
#  */
# ...
#
#
# All descriptive text is further processed, scanning for the following special
# patterns, which are highlighted appropriately.
#
# 'funcname()' - function
# '$ENVVAR' - environmental variable
# '&struct_name' - name of a structure (up to two words including 'struct')
# '&struct_name.member' - name of a structure member
# '@parameter' - name of a parameter
# '%CONST' - name of a constant.
# '``LITERAL``' - literal string without any spaces on it.

## init lots of data

my $errors = 0;
my $warnings = 0;
my $anon_struct_union = 0;

# match expressions used to find embedded type information
my $type_constant = '\b``([^\`]+)``\b';
my $type_constant2 = '\%([-_\w]+)';
my $type_func = '(\w+)\(\)';
my $type_param = '\@(\w*(\.\w+)*(\.\.\.)?)';
my $type_fp_param = '\@(\w+)\(\)';  # Special RST handling for func ptr params
my $type_env = '(\$\w+)';
my $type_enum = '\&(enum\s*([_\w]+))';
my $type_struct = '\&(struct\s*([_\w]+))';
my $type_typedef = '\&(typedef\s*([_\w]+))';
my $type_union = '\&(union\s*([_\w]+))';
my $type_member = '\&([_\w]+)(\.|->)([_\w]+)';
my $type_fallback = '\&([_\w]+)';
my $type_member_func = $type_member . '\(\)';

# Output conversion substitutions.
#  One for each output format

# these are pretty rough
my @highlights_man = (
                      [$type_constant, "\$1"],
                      [$type_constant2, "\$1"],
                      [$type_func, "\\\\fB\$1\\\\fP"],
                      [$type_enum, "\\\\fI\$1\\\\fP"],
                      [$type_struct, "\\\\fI\$1\\\\fP"],
                      [$type_typedef, "\\\\fI\$1\\\\fP"],
                      [$type_union, "\\\\fI\$1\\\\fP"],
                      [$type_param, "\\\\fI\$1\\\\fP"],
                      [$type_member, "\\\\fI\$1\$2\$3\\\\fP"],
                      [$type_fallback, "\\\\fI\$1\\\\fP"]
		     );
my $blankline_man = "";

# rst-mode
my @highlights_rst = (
                       [$type_constant, "``\$1``"],
                       [$type_constant2, "``\$1``"],
                       # Note: need to escape () to avoid func matching later
                       [$type_member_func, "\\:c\\:type\\:`\$1\$2\$3\\\\(\\\\) <\$1>`"],
                       [$type_member, "\\:c\\:type\\:`\$1\$2\$3 <\$1>`"],
		       [$type_fp_param, "**\$1\\\\(\\\\)**"],
                       [$type_func, "\\:c\\:func\\:`\$1()`"],
                       [$type_enum, "\\:c\\:type\\:`\$1 <\$2>`"],
                       [$type_struct, "\\:c\\:type\\:`\$1 <\$2>`"],
                       [$type_typedef, "\\:c\\:type\\:`\$1 <\$2>`"],
                       [$type_union, "\\:c\\:type\\:`\$1 <\$2>`"],
                       # in rst this can refer to any type
                       [$type_fallback, "\\:c\\:type\\:`\$1`"],
                       [$type_param, "**\$1**"]
		      );
my $blankline_rst = "\n";

# read arguments
if ($#ARGV == -1) {
    usage();
}

my $kernelversion;
my $dohighlight = "";

my $verbose = 0;
my $output_mode = "rst";
my $output_preformatted = 0;
my $no_doc_sections = 0;
my $enable_lineno = 0;
my @highlights = @highlights_rst;
my $blankline = $blankline_rst;
my $modulename = "Kernel API";

use constant {
    OUTPUT_ALL          => 0, # output all symbols and doc sections
    OUTPUT_INCLUDE      => 1, # output only specified symbols
    OUTPUT_EXCLUDE      => 2, # output everything except specified symbols
    OUTPUT_EXPORTED     => 3, # output exported symbols
    OUTPUT_INTERNAL     => 4, # output non-exported symbols
};
my $output_selection = OUTPUT_ALL;
my $show_not_found = 0;

my @export_file_list;

my @build_time;
if (defined($ENV{'KBUILD_BUILD_TIMESTAMP'}) &&
    (my $seconds = `date -d"${ENV{'KBUILD_BUILD_TIMESTAMP'}}" +%s`) ne '') {
    @build_time = gmtime($seconds);
} else {
    @build_time = localtime;
}

my $man_date = ('January', 'February', 'March', 'April', 'May', 'June',
		'July', 'August', 'September', 'October',
		'November', 'December')[$build_time[4]] .
  " " . ($build_time[5]+1900);

# Essentially these are globals.
# They probably want to be tidied up, made more localised or something.
# CAVEAT EMPTOR!  Some of the others I localised may not want to be, which
# could cause "use of undefined value" or other bugs.
my ($function, %function_table, %parametertypes, $declaration_purpose);
my $declaration_start_line;
my ($type, $declaration_name, $return_type);
my ($newsection, $newcontents, $prototype, $brcount, %source_map);

if (defined($ENV{'KBUILD_VERBOSE'})) {
	$verbose = "$ENV{'KBUILD_VERBOSE'}";
}

# Generated docbook code is inserted in a template at a point where
# docbook v3.1 requires a non-zero sequence of RefEntry's; see:
# http://www.oasis-open.org/docbook/documentation/reference/html/refentry.html
# We keep track of number of generated entries and generate a dummy
# if needs be to ensure the expanded template can be postprocessed
# into html.
my $section_counter = 0;

my $lineprefix="";

# Parser states
use constant {
    STATE_NORMAL        => 0, # normal code
    STATE_NAME          => 1, # looking for function name
    STATE_BODY_MAYBE    => 2, # body - or maybe more description
    STATE_BODY          => 3, # the body of the comment
    STATE_PROTO         => 4, # scanning prototype
    STATE_DOCBLOCK      => 5, # documentation block
    STATE_INLINE        => 6, # gathering documentation outside main block
};
my $state;
my $in_doc_sect;
my $leading_space;

# Inline documentation state
use constant {
    STATE_INLINE_NA     => 0, # not applicable ($state != STATE_INLINE)
    STATE_INLINE_NAME   => 1, # looking for member name (@foo:)
    STATE_INLINE_TEXT   => 2, # looking for member documentation
    STATE_INLINE_END    => 3, # done
    STATE_INLINE_ERROR  => 4, # error - Comment without header was found.
                              # Spit a warning as it's not
                              # proper kernel-doc and ignore the rest.
};
my $inline_doc_state;

#declaration types: can be
# 'function', 'struct', 'union', 'enum', 'typedef'
my $decl_type;

my $doc_start = '^/\*\*\s*$'; # Allow whitespace at end of comment start.
my $doc_end = '\*/';
my $doc_com = '\s*\*\s*';
my $doc_com_body = '\s*\* ?';
my $doc_decl = $doc_com . '(\w+)';
# @params and a strictly limited set of supported section names
my $doc_sect = $doc_com . 
    '\s*(\@[.\w]+|\@\.\.\.|description|context|returns?|notes?|examples?)\s*:(.*)';
my $doc_content = $doc_com_body . '(.*)';
my $doc_block = $doc_com . 'DOC:\s*(.*)?';
my $doc_inline_start = '^\s*/\*\*\s*$';
my $doc_inline_sect = '\s*\*\s*(@[\w\s]+):(.*)';
my $doc_inline_end = '^\s*\*/\s*$';
my $doc_inline_oneline = '^\s*/\*\*\s*(@[\w\s]+):\s*(.*)\s*\*/\s*$';
my $export_symbol = '^\s*EXPORT_SYMBOL(_GPL)?\s*\(\s*(\w+)\s*\)\s*;';

my %parameterdescs;
my %parameterdesc_start_lines;
my @parameterlist;
my %sections;
my @sectionlist;
my %section_start_lines;
my $sectcheck;
my $struct_actual;

my $contents = "";
my $new_start_line = 0;

# the canonical section names. see also $doc_sect above.
my $section_default = "Description";	# default section
my $section_intro = "Introduction";
my $section = $section_default;
my $section_context = "Context";
my $section_return = "Return";

my $undescribed = "-- undescribed --";

reset_state();

while ($ARGV[0] =~ m/^--?(.*)/) {
    my $cmd = $1;
    shift @ARGV;
    if ($cmd eq "man") {
	$output_mode = "man";
	@highlights = @highlights_man;
	$blankline = $blankline_man;
    } elsif ($cmd eq "rst") {
	$output_mode = "rst";
	@highlights = @highlights_rst;
	$blankline = $blankline_rst;
    } elsif ($cmd eq "none") {
	$output_mode = "none";
    } elsif ($cmd eq "module") { # not needed for XML, inherits from calling document
	$modulename = shift @ARGV;
    } elsif ($cmd eq "function") { # to only output specific functions
	$output_selection = OUTPUT_INCLUDE;
	$function = shift @ARGV;
	$function_table{$function} = 1;
    } elsif ($cmd eq "nofunction") { # output all except specific functions
	$output_selection = OUTPUT_EXCLUDE;
	$function = shift @ARGV;
	$function_table{$function} = 1;
    } elsif ($cmd eq "export") { # only exported symbols
	$output_selection = OUTPUT_EXPORTED;
	%function_table = ();
    } elsif ($cmd eq "internal") { # only non-exported symbols
	$output_selection = OUTPUT_INTERNAL;
	%function_table = ();
    } elsif ($cmd eq "export-file") {
	my $file = shift @ARGV;
	push(@export_file_list, $file);
    } elsif ($cmd eq "v") {
	$verbose = 1;
    } elsif (($cmd eq "h") || ($cmd eq "help")) {
	usage();
    } elsif ($cmd eq 'no-doc-sections') {
	    $no_doc_sections = 1;
    } elsif ($cmd eq 'enable-lineno') {
	    $enable_lineno = 1;
    } elsif ($cmd eq 'show-not-found') {
	$show_not_found = 1;
    } else {
	# Unknown argument
        usage();
    }
}

# continue execution near EOF;

# get kernel version from env
sub get_kernel_version() {
    my $version = 'unknown kernel version';

    if (defined($ENV{'KERNELVERSION'})) {
	$version = $ENV{'KERNELVERSION'};
    }
    return $version;
}

#
sub print_lineno {
    my $lineno = shift;
    if ($enable_lineno && defined($lineno)) {
        print "#define LINENO " . $lineno . "\n";
    }
}
##
# dumps section contents to arrays/hashes intended for that purpose.
#
sub dump_section {
    my $file = shift;
    my $name = shift;
    my $contents = join "\n", @_;

    if ($name =~ m/$type_param/) {
	$name = $1;
	$parameterdescs{$name} = $contents;
	$sectcheck = $sectcheck . $name . " ";
        $parameterdesc_start_lines{$name} = $new_start_line;
        $new_start_line = 0;
    } elsif ($name eq "@\.\.\.") {
	$name = "...";
	$parameterdescs{$name} = $contents;
	$sectcheck = $sectcheck . $name . " ";
        $parameterdesc_start_lines{$name} = $new_start_line;
        $new_start_line = 0;
    } else {
	if (defined($sections{$name}) && ($sections{$name} ne "")) {
	    # Only warn on user specified duplicate section names.
	    if ($name ne $section_default) {
		print STDERR "${file}:$.: warning: duplicate section name '$name'\n";
		++$warnings;
	    }
	    $sections{$name} .= $contents;
	} else {
	    $sections{$name} = $contents;
	    push @sectionlist, $name;
            $section_start_lines{$name} = $new_start_line;
            $new_start_line = 0;
	}
    }
}

##
# dump DOC: section after checking that it should go out
#
sub dump_doc_section {
    my $file = shift;
    my $name = shift;
    my $contents = join "\n", @_;

    if ($no_doc_sections) {
        return;
    }

    if (($output_selection == OUTPUT_ALL) ||
	($output_selection == OUTPUT_INCLUDE &&
	 defined($function_table{$name})) ||
	($output_selection == OUTPUT_EXCLUDE &&
	 !defined($function_table{$name})))
    {
	dump_section($file, $name, $contents);
	output_blockhead({'sectionlist' => \@sectionlist,
			  'sections' => \%sections,
			  'module' => $modulename,
			  'content-only' => ($output_selection != OUTPUT_ALL), });
    }
}

##
# output function
#
# parameterdescs, a hash.
#  function => "function name"
#  parameterlist => @list of parameters
#  parameterdescs => %parameter descriptions
#  sectionlist => @list of sections
#  sections => %section descriptions
#

sub output_highlight {
    my $contents = join "\n",@_;
    my $line;

#   DEBUG
#   if (!defined $contents) {
#	use Carp;
#	confess "output_highlight got called with no args?\n";
#   }

#   print STDERR "contents b4:$contents\n";
    eval $dohighlight;
    die $@ if $@;
#   print STDERR "contents af:$contents\n";

    foreach $line (split "\n", $contents) {
	if (! $output_preformatted) {
	    $line =~ s/^\s*//;
	}
	if ($line eq ""){
	    if (! $output_preformatted) {
		print $lineprefix, $blankline;
	    }
	} else {
	    if ($output_mode eq "man" && substr($line, 0, 1) eq ".") {
		print "\\&$line";
	    } else {
		print $lineprefix, $line;
	    }
	}
	print "\n";
    }
}

##
# output function in man
sub output_function_man(%) {
    my %args = %{$_[0]};
    my ($parameter, $section);
    my $count;

    print ".TH \"$args{'function'}\" 9 \"$args{'function'}\" \"$man_date\" \"Kernel Hacker's Manual\" LINUX\n";

    print ".SH NAME\n";
    print $args{'function'} . " \\- " . $args{'purpose'} . "\n";

    print ".SH SYNOPSIS\n";
    if ($args{'functiontype'} ne "") {
	print ".B \"" . $args{'functiontype'} . "\" " . $args{'function'} . "\n";
    } else {
	print ".B \"" . $args{'function'} . "\n";
    }
    $count = 0;
    my $parenth = "(";
    my $post = ",";
    foreach my $parameter (@{$args{'parameterlist'}}) {
	if ($count == $#{$args{'parameterlist'}}) {
	    $post = ");";
	}
	$type = $args{'parametertypes'}{$parameter};
	if ($type =~ m/([^\(]*\(\*)\s*\)\s*\(([^\)]*)\)/) {
	    # pointer-to-function
	    print ".BI \"" . $parenth . $1 . "\" " . $parameter . " \") (" . $2 . ")" . $post . "\"\n";
	} else {
	    $type =~ s/([^\*])$/$1 /;
	    print ".BI \"" . $parenth . $type . "\" " . $parameter . " \"" . $post . "\"\n";
	}
	$count++;
	$parenth = "";
    }

    print ".SH ARGUMENTS\n";
    foreach $parameter (@{$args{'parameterlist'}}) {
	my $parameter_name = $parameter;
	$parameter_name =~ s/\[.*//;

	print ".IP \"" . $parameter . "\" 12\n";
	output_highlight($args{'parameterdescs'}{$parameter_name});
    }
    foreach $section (@{$args{'sectionlist'}}) {
	print ".SH \"", uc $section, "\"\n";
	output_highlight($args{'sections'}{$section});
    }
}

##
# output enum in man
sub output_enum_man(%) {
    my %args = %{$_[0]};
    my ($parameter, $section);
    my $count;

    print ".TH \"$args{'module'}\" 9 \"enum $args{'enum'}\" \"$man_date\" \"API Manual\" LINUX\n";

    print ".SH NAME\n";
    print "enum " . $args{'enum'} . " \\- " . $args{'purpose'} . "\n";

    print ".SH SYNOPSIS\n";
    print "enum " . $args{'enum'} . " {\n";
    $count = 0;
    foreach my $parameter (@{$args{'parameterlist'}}) {
	print ".br\n.BI \"    $parameter\"\n";
	if ($count == $#{$args{'parameterlist'}}) {
	    print "\n};\n";
	    last;
	}
	else {
	    print ", \n.br\n";
	}
	$count++;
    }

    print ".SH Constants\n";
    foreach $parameter (@{$args{'parameterlist'}}) {
	my $parameter_name = $parameter;
	$parameter_name =~ s/\[.*//;

	print ".IP \"" . $parameter . "\" 12\n";
	output_highlight($args{'parameterdescs'}{$parameter_name});
    }
    foreach $section (@{$args{'sectionlist'}}) {
	print ".SH \"$section\"\n";
	output_highlight($args{'sections'}{$section});
    }
}

##
# output struct in man
sub output_struct_man(%) {
    my %args = %{$_[0]};
    my ($parameter, $section);

    print ".TH \"$args{'module'}\" 9 \"" . $args{'type'} . " " . $args{'struct'} . "\" \"$man_date\" \"API Manual\" LINUX\n";

    print ".SH NAME\n";
    print $args{'type'} . " " . $args{'struct'} . " \\- " . $args{'purpose'} . "\n";

    my $declaration = $args{'definition'};
    $declaration =~ s/\t/  /g;
    $declaration =~ s/\n/"\n.br\n.BI \"/g;
    print ".SH SYNOPSIS\n";
    print $args{'type'} . " " . $args{'struct'} . " {\n.br\n";
    print ".BI \"$declaration\n};\n.br\n\n";

    print ".SH Members\n";
    foreach $parameter (@{$args{'parameterlist'}}) {
	($parameter =~ /^#/) && next;

	my $parameter_name = $parameter;
	$parameter_name =~ s/\[.*//;

	($args{'parameterdescs'}{$parameter_name} ne $undescribed) || next;
	print ".IP \"" . $parameter . "\" 12\n";
	output_highlight($args{'parameterdescs'}{$parameter_name});
    }
    foreach $section (@{$args{'sectionlist'}}) {
	print ".SH \"$section\"\n";
	output_highlight($args{'sections'}{$section});
    }
}

##
# output typedef in man
sub output_typedef_man(%) {
    my %args = %{$_[0]};
    my ($parameter, $section);

    print ".TH \"$args{'module'}\" 9 \"$args{'typedef'}\" \"$man_date\" \"API Manual\" LINUX\n";

    print ".SH NAME\n";
    print "typedef " . $args{'typedef'} . " \\- " . $args{'purpose'} . "\n";

    foreach $section (@{$args{'sectionlist'}}) {
	print ".SH \"$section\"\n";
	output_highlight($args{'sections'}{$section});
    }
}

sub output_blockhead_man(%) {
    my %args = %{$_[0]};
    my ($parameter, $section);
    my $count;

    print ".TH \"$args{'module'}\" 9 \"$args{'module'}\" \"$man_date\" \"API Manual\" LINUX\n";

    foreach $section (@{$args{'sectionlist'}}) {
	print ".SH \"$section\"\n";
	output_highlight($args{'sections'}{$section});
    }
}

##
# output in restructured text
#

#
# This could use some work; it's used to output the DOC: sections, and
# starts by putting out the name of the doc section itself, but that tends
# to duplicate a header already in the template file.
#
sub output_blockhead_rst(%) {
    my %args = %{$_[0]};
    my ($parameter, $section);

    foreach $section (@{$args{'sectionlist'}}) {
	if ($output_selection != OUTPUT_INCLUDE) {
	    print "**$section**\n\n";
	}
        print_lineno($section_start_lines{$section});
	output_highlight_rst($args{'sections'}{$section});
	print "\n";
    }
}

sub output_highlight_rst {
    my $contents = join "\n",@_;
    my $line;

    eval $dohighlight;
    die $@ if $@;

    foreach $line (split "\n", $contents) {
	print $lineprefix . $line . "\n";
    }
}

sub output_function_rst(%) {
    my %args = %{$_[0]};
    my ($parameter, $section);
    my $oldprefix = $lineprefix;
    my $start = "";

    if ($args{'typedef'}) {
	print ".. c:type:: ". $args{'function'} . "\n\n";
	print_lineno($declaration_start_line);
	print "   **Typedef**: ";
	$lineprefix = "";
	output_highlight_rst($args{'purpose'});
	$start = "\n\n**Syntax**\n\n  ``";
    } else {
	print ".. c:function:: ";
    }
    if ($args{'functiontype'} ne "") {
	$start .= $args{'functiontype'} . " " . $args{'function'} . " (";
    } else {
	$start .= $args{'function'} . " (";
    }
    print $start;

    my $count = 0;
    foreach my $parameter (@{$args{'parameterlist'}}) {
	if ($count ne 0) {
	    print ", ";
	}
	$count++;
	$type = $args{'parametertypes'}{$parameter};

	if ($type =~ m/([^\(]*\(\*)\s*\)\s*\(([^\)]*)\)/) {
	    # pointer-to-function
	    print $1 . $parameter . ") (" . $2;
	} else {
	    print $type . " " . $parameter;
	}
    }
    if ($args{'typedef'}) {
	print ");``\n\n";
    } else {
	print ")\n\n";
	print_lineno($declaration_start_line);
	$lineprefix = "   ";
	output_highlight_rst($args{'purpose'});
	print "\n";
    }

    print "**Parameters**\n\n";
    $lineprefix = "  ";
    foreach $parameter (@{$args{'parameterlist'}}) {
	my $parameter_name = $parameter;
	$parameter_name =~ s/\[.*//;
	$type = $args{'parametertypes'}{$parameter};

	if ($type ne "") {
	    print "``$type $parameter``\n";
	} else {
	    print "``$parameter``\n";
	}

        print_lineno($parameterdesc_start_lines{$parameter_name});

	if (defined($args{'parameterdescs'}{$parameter_name}) &&
	    $args{'parameterdescs'}{$parameter_name} ne $undescribed) {
	    output_highlight_rst($args{'parameterdescs'}{$parameter_name});
	} else {
	    print "  *undescribed*\n";
	}
	print "\n";
    }

    $lineprefix = $oldprefix;
    output_section_rst(@_);
}

sub output_section_rst(%) {
    my %args = %{$_[0]};
    my $section;
    my $oldprefix = $lineprefix;
    $lineprefix = "";

    foreach $section (@{$args{'sectionlist'}}) {
	print "**$section**\n\n";
        print_lineno($section_start_lines{$section});
	output_highlight_rst($args{'sections'}{$section});
	print "\n";
    }
    print "\n";
    $lineprefix = $oldprefix;
}

sub output_enum_rst(%) {
    my %args = %{$_[0]};
    my ($parameter);
    my $oldprefix = $lineprefix;
    my $count;
    my $name = "enum " . $args{'enum'};

    print "\n\n.. c:type:: " . $name . "\n\n";
    print_lineno($declaration_start_line);
    $lineprefix = "   ";
    output_highlight_rst($args{'purpose'});
    print "\n";

    print "**Constants**\n\n";
    $lineprefix = "  ";
    foreach $parameter (@{$args{'parameterlist'}}) {
	print "``$parameter``\n";
	if ($args{'parameterdescs'}{$parameter} ne $undescribed) {
	    output_highlight_rst($args{'parameterdescs'}{$parameter});
	} else {
	    print "  *undescribed*\n";
	}
	print "\n";
    }

    $lineprefix = $oldprefix;
    output_section_rst(@_);
}

sub output_typedef_rst(%) {
    my %args = %{$_[0]};
    my ($parameter);
    my $oldprefix = $lineprefix;
    my $name = "typedef " . $args{'typedef'};

    print "\n\n.. c:type:: " . $name . "\n\n";
    print_lineno($declaration_start_line);
    $lineprefix = "   ";
    output_highlight_rst($args{'purpose'});
    print "\n";

    $lineprefix = $oldprefix;
    output_section_rst(@_);
}

sub output_struct_rst(%) {
    my %args = %{$_[0]};
    my ($parameter);
    my $oldprefix = $lineprefix;
    my $name = $args{'type'} . " " . $args{'struct'};

    print "\n\n.. c:type:: " . $name . "\n\n";
    print_lineno($declaration_start_line);
    $lineprefix = "   ";
    output_highlight_rst($args{'purpose'});
    print "\n";

    print "**Definition**\n\n";
    print "::\n\n";
    my $declaration = $args{'definition'};
    $declaration =~ s/\t/  /g;
    print "  " . $args{'type'} . " " . $args{'struct'} . " {\n$declaration  };\n\n";

    print "**Members**\n\n";
    $lineprefix = "  ";
    foreach $parameter (@{$args{'parameterlist'}}) {
	($parameter =~ /^#/) && next;

	my $parameter_name = $parameter;
	$parameter_name =~ s/\[.*//;

	($args{'parameterdescs'}{$parameter_name} ne $undescribed) || next;
	$type = $args{'parametertypes'}{$parameter};
        print_lineno($parameterdesc_start_lines{$parameter_name});
	print "``" . $parameter . "``\n";
	output_highlight_rst($args{'parameterdescs'}{$parameter_name});
	print "\n";
    }
    print "\n";

    $lineprefix = $oldprefix;
    output_section_rst(@_);
}

## none mode output functions

sub output_function_none(%) {
}

sub output_enum_none(%) {
}

sub output_typedef_none(%) {
}

sub output_struct_none(%) {
}

sub output_blockhead_none(%) {
}

##
# generic output function for all types (function, struct/union, typedef, enum);
# calls the generated, variable output_ function name based on
# functype and output_mode
sub output_declaration {
    no strict 'refs';
    my $name = shift;
    my $functype = shift;
    my $func = "output_${functype}_$output_mode";
    if (($output_selection == OUTPUT_ALL) ||
	(($output_selection == OUTPUT_INCLUDE ||
	  $output_selection == OUTPUT_EXPORTED) &&
	 defined($function_table{$name})) ||
	(($output_selection == OUTPUT_EXCLUDE ||
	  $output_selection == OUTPUT_INTERNAL) &&
	 !($functype eq "function" && defined($function_table{$name}))))
    {
	&$func(@_);
	$section_counter++;
    }
}

##
# generic output function - calls the right one based on current output mode.
sub output_blockhead {
    no strict 'refs';
    my $func = "output_blockhead_" . $output_mode;
    &$func(@_);
    $section_counter++;
}

##
# takes a declaration (struct, union, enum, typedef) and
# invokes the right handler. NOT called for functions.
sub dump_declaration($$) {
    no strict 'refs';
    my ($prototype, $file) = @_;
    my $func = "dump_" . $decl_type;
    &$func(@_);
}

sub dump_union($$) {
    dump_struct(@_);
}