Adding command to search C99 draft standard

modules/cstd.pl

@@ -0,0 +1,179 @@
+#!/usr/bin/perl
+
+use warnings;
+use strict;
+
+my $search = join ' ', @ARGV;
+
+if(not length $search) {
+  print "Usage: cstd [-list] [-n #] [-section <section>] [search text] -- 'section' must be in the form of X.YpZ where X and Y are section/chapter and, optionally, Z is paragraph. If both 'section' and 'search text' are specified, then the search space will be within the specified section. You may use -n # to skip to the #th match. To list only the section numbers containing 'search text', add -list.\n";
+  exit 0;
+}
+
+my ($section, $paragraph, $section_specified, $paragraph_specified, $match, $list_only);
+
+if($search =~ s/-section ([0-9\.p]+)//i) {
+  $section = $1;
+
+  if($section =~ s/p(\d+)//i) {
+    $paragraph = $1;
+    $paragraph_specified = 1;
+  } else {
+    $paragraph = 1;
+  }
+
+  $section = "$section." if $section =~ m/^\d+$/;
+
+  $section_specified = 1;
+}
+
+if($search =~ s/-n\s*(\d+)//) {
+  $match = $1;
+} else {
+  $match = 1;
+}
+
+if($search =~ s/-list//i) {
+  $list_only = 1;
+}
+
+$search =~ s/^\s+//;
+$search =~ s/\s+$//;
+
+if(not defined $section) {
+  $section = "1.";
+  $paragraph = 1;
+}
+
+if($list_only and not length $search) {
+  print "You must specify some search text to use with -list.\n";
+  exit 0;
+}
+
+open FH, "<n1256.txt" or die "Could not open n1256.txt: $!";
+my @contents = <FH>;
+close FH;
+
+my $text = join '', @contents;
+$text =~ s/\r//g;
+
+my $result;
+my $section_title;
+my $found = 0;
+my $matches = 0;
+my $this_section;
+my $comma = "";
+
+#print "search: [$search]; section: [$section]\n";
+
+if($list_only) {
+  $result = "Sections containing '$search': ";
+}
+
+$search =~ s/\s+/.*/g;
+
+while($text =~ m/^(\d+\.[0-9\.]*)/msg) {
+  $this_section = $1;
+
+  my $section_text;
+
+  if($text =~ m/(.*?)^(?=\d+\.)/msg) {
+    $section_text = $1;
+  } else {
+    last;
+  }
+
+  if($section_text =~ m/(.*?)$/msg) {
+    $section_title = $1 if length $1;
+    $section_title =~ s/^\s+//;
+    $section_title =~ s/\s+$//;
+  }
+
+  if(not defined $section_text) {
+    print "Fatal error: no section text\n";
+    die;
+  }
+
+  if($section_specified) {
+    next if $this_section !~ m/^$section/;
+  }
+
+#  print "----------------------------------\n";
+#  print "$this_section text: [$section_text]\n";
+
+  while($section_text =~ m/^(\d+)\s(.*?)^(?=\d)/msgc or $section_text =~ m/^(\d+)\s(.*)/msg) {
+    my $p = $1;
+    my $t = $2;
+    
+    if($paragraph_specified and not length $search and $p == $paragraph) {
+      $found = 1;
+      $result = $t;
+      last;
+    }
+
+    if(length $search) {
+
+      #     print "$p\n";
+      #     print "[$t]\n";
+
+      if($t =~ m/$search/msi) {
+        $matches++;
+        if($matches >= $match) {
+          if($list_only) {
+            $result .= "$comma$this_section" . "p" . $p;
+            $comma = ", ";
+          } else {
+            $result = $t;
+            $paragraph = $p;
+            $paragraph_specified = 1;
+            $found = 1;
+            last;
+          }
+        }
+      }
+    }
+  }
+
+  last if $found == 1;
+
+  if($paragraph_specified) {
+    print "No such paragraph '$paragraph' in section '$section' of n1256.\n";
+    exit 0;
+  }
+
+  if(defined $section_specified and not length $search) {
+    $found = 1;
+    $result = $section_text;
+    last;
+  }
+
+  $paragraph = 1;
+}
+
+if(not $found and $comma eq "") {
+  $search =~ s/\.\*/ /g;
+  if($section_specified) {
+    print "No such text '$search' found within section '$section' in n1256.\n" if length $search;
+    print "No such section '$section' in n1256.\n" if not length $search;
+    exit 0;
+  }
+
+  print "No such section '$section' in n1256.\n" if not length $search;
+  print "No such text '$search' found in n1256.\n" if length $search;
+  exit 0;
+}
+
+$result =~ s/$section_title// if length $section_title;
+$result =~ s/^\s+//;
+$result =~ s/\s+$//;
+$result =~ s/\s+/ /g;
+$result =~ s/[\n\r]/ /g;
+
+if($comma eq "") {
+  print $this_section;
+  print "p" . $paragraph if $paragraph_specified;
+  print ": ";
+  print "[", $section_title, "] " if length $section_title;
+}
+
+print "$result\n";