[padb-devel] [padb] r246 committed - Use a function dispatch table to avoid a large if/elsif table when pro...

[codesite-noreply at google.com]

Revision: 246
Author: apittman
Date: Mon Sep 14 05:06:47 2009
Log: Use a function dispatch table to avoid a large if/elsif table when  
processing
requests from minfo.

http://code.google.com/p/padb/source/detail?r=246

Modified:
  /branches/cleanup/src/padb

=======================================
--- /branches/cleanup/src/padb	Sun Sep 13 16:09:04 2009
+++ /branches/cleanup/src/padb	Mon Sep 14 05:06:47 2009
@@ -4155,7 +4155,6 @@

      my $pcmd = {
          pid => -1,
-        in  => "",
          out => *OUT,
          err => *ERR,
      };
@@ -5243,10 +5242,10 @@
  }

  sub gdb_string {
-    my ( $gdb, $strp ) = @_;
+    my ( $gdb, $len, $strp ) = @_;
      my $offset = 0;
      my $str    = $EMPTY_STRING;
-    my @s      = gdb_read_raw( $gdb, $strp, 128 );
+    my @s      = gdb_read_raw( $gdb, $strp, $len );
      return if ( not defined $s[0] );
      foreach my $d (@s) {
          my $v = hex $d;
@@ -5259,38 +5258,35 @@
  sub minfo_handle_query {
      my ( $gdb, $vp, $query, $stats ) = @_;

-    # Shouldn't this be?
      my ( undef, $cmd, @params ) = split $SPACE, $query;
      my $res;
      return 'fail' unless defined $cmd;
-    if ( $cmd eq 'size' ) {
-        $res = gdb_type_size( $gdb, $params[0] );
-        $stats->{size}++;
-    } elsif ( $cmd eq 'offset' ) {
-        $res = gdb_type_offset( $gdb, $params[0], $params[1] );
-        $stats->{offset}++;
-    } elsif ( $cmd eq 'string' ) {
-        my $str = gdb_string( $gdb, $params[1] );
-        if ( defined $str ) {
-            $stats->{string}++;
-            $res = $str;
-        }
-    } elsif ( $cmd eq 'func' ) {
-        $res = gdb_func_addr( $gdb, $params[0] );
-        $stats->{function}++;
-    } elsif ( $cmd eq 'sym' ) {
-        $res = gdb_var_addr( $gdb, $params[0] );
-        $stats->{symbol}++;
+
+    $stats->{$cmd}++;
+
+    my %dispatch_1 = (
+        size => \&gdb_type_size,
+        func => \&gdb_func_addr,
+        sym  => \&gdb_var_addr,
+    );
+
+    my %dispatch_2 = (
+        offset => \&gdb_type_offset,
+        string => \&gdb_string,
+    );
+
+    if ( defined $dispatch_1{$cmd} ) {
+        $res = $dispatch_1{$cmd}( $gdb, $params[0] );
+    } elsif ( defined $dispatch_2{$cmd} ) {
+        $res = $dispatch_2{$cmd}( $gdb, $params[0], $params[1] );
      } elsif ( $cmd eq 'data' ) {
          my @r = gdb_read_raw( $gdb, $params[0], $params[1] );
          if ( defined $r[0] ) {
              $res = "@r";
-            $stats->{datareads}++;
              $stats->{databytes} += $params[1];
          }
      } elsif ( $cmd eq 'rank' ) {
          $res = $vp;
-        $stats->{rank}++;
      } elsif ( $cmd eq 'image' ) {
          my $image = readlink "/proc/$gdb->{tracepid}/exe";
          if ( defined $image ) {
@@ -5314,19 +5310,16 @@
          hpid     => -1,
          tracepid => -1,
          attached => 0,
-        rdr      => "",
-        wtr      => "",
-        err      => "",
      };
      my @mq;

      my $cmd = $inner_conf{minfo};
-    $h->{hpid} = open3( $h->{wtr}, $h->{rdr}, $h->{err}, $cmd )
+    $h->{hpid} = open3( $h->{fd}{wtr}, $h->{fd}{rdr}, $h->{fd}{err}, $cmd )
        or confess "Unable to popen() h: $!\n";

-    my $handle = $h->{rdr};
-
-    my $out = $h->{wtr};
+    my $handle = $h->{fd}{rdr};
+
+    my $out = $h->{fd}{wtr};

      my %stats;

@@ -5335,11 +5328,10 @@
          chomp $r;
          if ( $r =~ m{\Areq:}x ) {
              my $res = minfo_handle_query( $gdb, $vp, $r, \%stats );
-            if ( defined $res ) {
-                print {$out} "$res\n";
-            }
-
-            # Some things *do* fail here, symbol lookups
+
+            print {$out} "$res\n";
+
+            # Some things *do* fail here, symbol lookups for example.
              # and we don't need to report it.
              if ( $res eq 'fail' ) {
                  debug( $vp, "Failed dll request $r\n" );
@@ -5352,9 +5344,9 @@
      my $sc = keys %stats;

      waitpid $h->{hpid}, 0;
-    close $h->{rdr};
-    close $h->{wtr};
-    close $h->{err};
+    foreach my $fd ( values %{ $h->{fd} } ) {
+        close $fd;
+    }

      if ( $sc == 0 ) {