--- commit-email.pl	2004-11-15 18:08:16.000000000 +0000
+++ commit-email.pl.new	2005-01-12 20:08:30.000000000 +0000
@@ -103,7 +103,8 @@
                        '-l'     => 'log_file',
                        '-m'     => '',
                        '-r'     => 'reply_to',
-                       '-s'     => 'subject_prefix');
+                       '-s'     => 'subject_prefix',
+                       '-n'     => 'num_diff_lines');
 
 while (@ARGV)
   {
@@ -125,6 +126,10 @@
         if ($hash_key)
           {
             $current_project->{$hash_key} = $value;
+            if ($hash_key eq 'num_diff_lines' && $value !~ /^\d+$/)
+              {
+                die "$0: argument to command line option $arg must be numeric.\n";
+              }
           }
         else
           {
@@ -359,7 +364,6 @@
 push(@body, "Log:\n");
 push(@body, @log);
 push(@body, "\n");
-push(@body, map { /[\r\n]+$/ ? $_ : "$_\n" } @difflines);
 
 # Go through each project and see if there are any matches for this
 # project.  If so, send the log out.
@@ -385,6 +389,7 @@
     my $log_file        = $project->{log_file};
     my $reply_to        = $project->{reply_to};
     my $subject_prefix  = $project->{subject_prefix};
+    my $num_diff_lines  = $project->{num_diff_lines};
     my $subject;
 
     if ($commondir ne '')
@@ -453,6 +458,15 @@
         if (open(SENDMAIL, "| $command"))
           {
             print SENDMAIL @head, @body;
+            if ($num_diff_lines > 0 && $#difflines + 1 > $num_diff_lines)
+              {
+                @difflines = @difflines[0 .. $num_diff_lines - 1];
+                push(@difflines, "---------------------------------\n");
+                push(@difflines, "Diffs truncated at $num_diff_lines lines.\n");
+                push(@difflines, "---------------------------------\n");
+              }
+            @difflines = map { /[\r\n]+$/ ? $_ : "$_\n" } @difflines;
+            print SENDMAIL @difflines;
             close SENDMAIL
               or warn "$0: error in closing `$command' for writing: $!\n";
           }
@@ -491,6 +505,7 @@
       "  -m regex              Regular expression to match committed path\n",
       "  -r email_address      Email address for 'Reply-To:'\n",
       "  -s subject_prefix     Subject line prefix\n",
+      "  -n num_diff_lines     Maximum number of diff lines to include\n",
       "\n",
       "This script supports a single repository with multiple projects,\n",
       "where each project receives email only for commits that modify that\n",
@@ -522,7 +537,8 @@
           log_file        => '',
           match_regex     => '.',
           reply_to        => '',
-          subject_prefix  => ''};
+          subject_prefix  => '',
+          num_diff_lines  => ''};
 }
 
 # Start a child process safely without using /bin/sh.