scripts: get_abi.pl: change script to allow parsing in ReST mode

Right now, several ABI files won't parse as ReST, as they
contain severe violations to the spec, with makes the script
to crash.

So, the code has a sanity logic with escapes bad code and
cleans tags that can cause Sphinx to crash.

Add support for disabling this mode.

Right now, as enabling rst-mode causes crash, it is disabled
by default.

Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/34b691e3002e8987c24d851fe37640f95e506a92.1604042072.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scripts/get_abi.pl

@@ -12,8 +12,14 @@ my $man;
 my $debug;
 my $prefix="Documentation/ABI";
 
+#
+# If true, assumes that the description is formatted with ReST
+#
+my $description_is_rst = 0;
+
 GetOptions(
 	"debug|d+" => \$debug,
+	"rst-source!" => \$description_is_rst,
 	"dir=s" => \$prefix,
 	'help|?' => \$help,
 	man => \$man
@@ -137,14 +143,15 @@ sub parse_abi {
 					next;
 				}
 				if ($tag eq "description") {
-					next if ($content =~ m/^\s*$/);
-					if ($content =~ m/^(\s*)(.*)/) {
-						my $new_content = $2;
-						$space = $new_tag . $sep . $1;
-						while ($space =~ s/\t+/' ' x (length($&) * 8 - length($`) % 8)/e) {}
-						$space =~ s/./ /g;
-						$data{$what}->{$tag} .= "$new_content\n";
+					# Preserve initial spaces for the first line
+					$content = ' ' x length($new_tag) . $sep . $content;
+					$content =~ s,^(\s*):,$1 ,;
+					if ($content =~ m/^(\s*)(.*)$/) {
+						$space = $1;
+						$content = $2;
 					}
+					while ($space =~ s/\t+/' ' x (length($&) * 8 - length($`) % 8)/e) {}
+					$data{$what}->{$tag} .= $content;
 				} else {
 					$data{$what}->{$tag} = $content;
 				}
@@ -160,11 +167,15 @@ sub parse_abi {
 
 		if ($tag eq "description") {
 			if (!$data{$what}->{description}) {
-				next if (m/^\s*\n/);
+				s/^($space)//;
 				if (m/^(\s*)(.*)/) {
-					$space = $1;
-					while ($space =~ s/\t+/' ' x (length($&) * 8 - length($`) % 8)/e) {}
-					$data{$what}->{$tag} .= "$2\n";
+					my $sp = $1;
+					while ($sp =~ s/\t+/' ' x (length($&) * 8 - length($`) % 8)/e) {}
+					my $content = "$sp$2";
+
+					$content =~ s/^($space)//;
+
+					$data{$what}->{$tag} .= "$content";
 				}
 			} else {
 				my $content = $_;
@@ -274,23 +285,27 @@ sub output_rest {
 		print "Defined on file :ref:`$file <$fileref>`\n\n" if ($type ne "File");
 
 		my $desc = $data{$what}->{description};
-		$desc =~ s/^\s+//;
-
-		# Remove title markups from the description, as they won't work
-		$desc =~ s/\n[\-\*\=\^\~]+\n/\n/g;
 
 		if (!($desc =~ /^\s*$/)) {
-			if ($desc =~ m/\:\n/ || $desc =~ m/\n[\t ]+/  || $desc =~ m/[\x00-\x08\x0b-\x1f\x7b-\xff]/) {
-				# put everything inside a code block
-				$desc =~ s/\n/\n /g;
-
-				print "::\n\n";
-				print " $desc\n\n";
-			} else {
-				# Escape any special chars from description
-				$desc =~s/([\x00-\x08\x0b-\x1f\x21-\x2a\x2d\x2f\x3c-\x40\x5c\x5e-\x60\x7b-\xff])/\\$1/g;
-
+			if ($description_is_rst) {
 				print "$desc\n\n";
+			} else {
+				$desc =~ s/^\s+//;
+
+				# Remove title markups from the description, as they won't work
+				$desc =~ s/\n[\-\*\=\^\~]+\n/\n\n/g;
+
+				if ($desc =~ m/\:\n/ || $desc =~ m/\n[\t ]+/  || $desc =~ m/[\x00-\x08\x0b-\x1f\x7b-\xff]/) {
+					# put everything inside a code block
+					$desc =~ s/\n/\n /g;
+
+					print "::\n\n";
+					print " $desc\n\n";
+				} else {
+					# Escape any special chars from description
+					$desc =~s/([\x00-\x08\x0b-\x1f\x21-\x2a\x2d\x2f\x3c-\x40\x5c\x5e-\x60\x7b-\xff])/\\$1/g;
+					print "$desc\n\n";
+				}
 			}
 		} else {
 			print "DESCRIPTION MISSING for $what\n\n" if (!$data{$what}->{is_file});
@@ -382,7 +397,7 @@ abi_book.pl - parse the Linux ABI files and produce a ReST book.
 
 =head1 SYNOPSIS
 
-B<abi_book.pl> [--debug] [--man] [--help] [--dir=<dir>] <COMAND> [<ARGUMENT>]
+B<abi_book.pl> [--debug] [--man] [--help] --[(no-)rst-source] [--dir=<dir>] <COMAND> [<ARGUMENT>]
 
 Where <COMMAND> can be:
 
@@ -405,6 +420,13 @@ B<validate>              - validate the ABI contents
 Changes the location of the ABI search. By default, it uses
 the Documentation/ABI directory.
 
+=item B<--rst-source> and B<--no-rst-source>
+
+The input file may be using ReST syntax or not. Those two options allow
+selecting between a rst-compliant source ABI (--rst-source), or a
+plain text that may be violating ReST spec, so it requres some escaping
+logic (--no-rst-source).
+
 =item B<--debug>
 
 Put the script in verbose mode, useful for debugging. Can be called multiple