difflast.pl

   1 #!/usr/bin/perl -w
   2
   3 ###############################################################################
   4 # Name:     difflast.pl
   5 # Purpose:  Shows the difference between the current local version of the file
   6 #           and the last cvs revision
   7 # Version:  $Id$
   8 # Author:   VZ
   9 # Created:  23.12.99
  10 # Copyright:(c) Vadim Zeitlin 1999
  11 ###############################################################################
  12
  13 use strict;
  14
  15 my $CVS = "cvs -z3";    # the cvs command
  16
  17 # the regexp for cvs revision number
  18 my $RE_CVS_REV = "\\d+(?:\\.\\d+)+";
  19
  20 sub dec_rev($)
  21 {
  22     my $rev = $_[0];
  23
  24     # decrement the revision number to get the previos one
  25     $rev =~ s/(\d+)$/$1 - 1/e;
  26
  27     return $rev;
  28 }
  29
  30 sub get_last_rev($)
  31 {
  32     my $file = $_[0];
  33
  34     my $basename = $file;
  35     $basename =~ s@^.*/@@;
  36
  37     # first get the current version: try the Id RCS tag in the file itself
  38     # first, use "cvs status" if this fails
  39     if ( open(INPUT, $file) ) {
  40         while (<INPUT>) {
  41             # notice that we shouldn't have '$' followed by 'Id' or cvs will
  42             # substitute it!
  43             if ( /\$(Id): $basename,v ($RE_CVS_REV)/ ) {
  44                 return &dec_rev($2);
  45             }
  46         }
  47     }
  48
  49     open(INPUT, "$CVS -q status $file |") or return 0;
  50
  51     while (<INPUT>) {
  52         if ( /Working revision:\s+($RE_CVS_REV)/ ) {
  53             return &dec_rev($1);
  54         }
  55     }
  56
  57     return 0;
  58 }
  59
  60 sub process_file($)
  61 {
  62     my $file = $_[0];
  63     my $revlast = &get_last_rev($file);
  64
  65     if ( !$revlast ) {
  66         warn "Failed to get the last revision for $file, skipping.\n"
  67     }
  68     elsif ( $revlast =~ '\.0' ) {
  69         warn "No previous revision of the file $file.\n"
  70     }
  71     else {
  72         print `$CVS diff -b -kk -r $revlast $file`;
  73     }
  74 }
  75
  76 # entry point
  77
  78 die "Usage: $0 <filenames...>\n" if ( $#ARGV == -1 );
  79
  80 foreach my $file (@ARGV) { process_file($file); }
  81
  82 exit 0;