r90: Dodan --change u cp-update

[carnet-tools-cn.git] / cp-update

diff --git a/cp-update b/cp-update
index d5b2ab2..f4d66be 100755 (executable)
--- a/cp-update
+++ b/cp-update
@@ -3,6 +3,7 @@
 ## Copyright (C) 1998 Hrvoje Niksic
 ## Modification by Zeljko Boros (block entries, removing old entries)
 ## More options and use strict by Zoran Dzelajlija on 2004-02-24
+## Quite a few improvements by Damir Dzeko on 2005-03-18 (see bellow)
 ##
 ## This program is free software; you can redistribute it and/or modify
 ## it under the terms of the GNU General Public License as published by
@@ -22,7 +23,7 @@
 ## -> reformated code, introduced coding conventions
 ## -> increased reliability through atomic actualization
 ## -> everything is done in the memory - more mem, less i/o
-## -> removed append mode - in-place editing considered harmfull
+## -> removed append mode - in-place editing considered harmful
 ## -> added in-place mode as option
 
 use strict;
@@ -54,12 +55,16 @@ $UsageLong = "
            -r | --remove            Remove entry PACKAGE from FILE.
                                     Default is to add lines from stdin.
 
+           -x | --change            Modify existing block, or add it if
+                                    it does not exist but the begin mark
+                                    can be found.
+
            -m | --allow-multiple    Allow multiple blocks of the same type.
                                     By default, old blocks are replaced with
                                     the new one.
 
            -h | --help              Print this message (usage reference).
-           
+
                 --version           Print version message.
 
   - Placement control:
@@ -115,6 +120,7 @@ use constant INSERT_ON_TOP => 3;
 # InsertRemove modes
 use constant DO_REMOVE => 0;
 use constant DO_INSERT => 1;
+use constant DO_CHANGE => 2;
 
 # Operation defaults
 $InsertRemove = DO_INSERT;
@@ -139,6 +145,9 @@ while (@ARGV) {
   elsif (/^-r$/ || /^--remove$/) {
     $InsertRemove = DO_REMOVE;
   }
+  elsif (/^-x$/ || /^--change$/) {
+    $InsertRemove = DO_CHANGE;
+  }
   elsif (/^-m$/ || /^--allow-multi(?:ple)?$/) {
     $Multi = 1;
   }
@@ -190,6 +199,10 @@ while (@ARGV) {
     unshift(@ARGV, $_);
     last;
   }
+  
+  if ($Multi and DO_CHANGE == $InsertRemove) {
+    die "$ProgramName: Cannot use both `--change' and `--allow-multiple'\n";
+  }
 }
 
 $Package = shift  or  die $UsageShort;
@@ -239,7 +252,11 @@ do_it() and exit(0);
 
 sub do_it {
   slurp();
-  if (DO_INSERT == $InsertRemove) {
+  if (DO_CHANGE == $InsertRemove) {
+    $StdinContent = &stdin_content;
+    change() or add();
+  }
+  elsif (DO_INSERT == $InsertRemove) {
     $StdinContent = &stdin_content;
     del() unless $Multi;
     add();
@@ -338,6 +355,51 @@ sub del() {
   return scalar(@Lines); # whatever
 }
 
+sub change() {
+  my ($mytrailer, $mybegin, $myend) =
+    ($Trailer, $MarkBegin, $MarkEnd);
+
+  my ($bm_found, $em_found); # begin/end mark found indicator
+
+  # Make the strings regexp-friendly by quoting non-word chars.
+  $mybegin   =~ s/\W/\\$&/g;
+  $myend     =~ s/\W/\\$&/g;
+  $mytrailer =~ s/\W/\\$&/g;
+
+  my (@filtered, $done, $skip);
+  $done = 0; # job done once
+  $skip = 0; # skip original block
+  foreach (@Lines) {
+    if (! $done and $skip > 0) {
+      if (/^$myend(?:$mytrailer)?$/o) {
+        ++ $done; # skipped all that was to skip
+      } else {
+        ++ $skip; # count lines being skipped
+      }
+    }
+    elsif (0 == $skip and $_ =~ /^$mybegin(?:$mytrailer)?$/o) {
+      push (@filtered, $StdinContent);
+      $skip = 1;
+    }
+    else {
+      push (@filtered, $_)
+    }
+    # for safety check:
+    $bm_found = 1 if (/^$mybegin(?:$mytrailer)?$/o);
+    $em_found = 1 if (/^$myend(?:$mytrailer)?$/o);
+  }
+  if ($bm_found and $em_found) {
+    -- $skip; # correct the counter
+    DEBUG and print STDERR "Replaced block of $skip lines\n";
+    @Lines = @filtered;
+  }
+  elsif ($bm_found and ! $em_found) {
+    # safety exit    
+    die "$ProgramName: no end-mark after begin-mark!\n";
+  }
+  return $done;
+}
+
 # written by ddzeko@srce.hr, 2005-03-18
 # to improve reliabilitah :)
 #