[padb-devel] [padb commit] r112 - Collect together all the code which sends SIGCONT to a process

[codesite-noreply at google.com]

Author: apittman
Date: Fri Jul 17 10:09:46 2009
New Revision: 112

Modified:
    branches/full-duplex/src/padb

Log:
Collect together all the code which sends SIGCONT to a process
before attaching into a send_cont_signal() function.  Call this
function inside gdb_attach and gdb_detach to ensure it always gets
called.  We should probably read the process state and check if it's
T or not and warn the user if it is rather than just silently fixing
things up.


Modified: branches/full-duplex/src/padb
==============================================================================
--- branches/full-duplex/src/padb	(original)
+++ branches/full-duplex/src/padb	Fri Jul 17 10:09:46 2009
@@ -4196,6 +4196,7 @@
  sub gdb_attach {
      my ( $gdb, $pid ) = @_;

+    send_cont_signal($pid);
      my $result = gdb_send( $gdb, "attach $pid" );

      return unless defined $result;
@@ -4215,7 +4216,7 @@

      $gdb->{attached} = 0;

-    return $gdb->{tracepid};
+    send_cont_signal( $gdb->{tracepid} );
  }

  sub gdb_wait_for_prompt {
@@ -4671,10 +4672,19 @@
      return @mq;
  }

+# Send a CONT signal to a pid, there have been problems where a program
+# is in "T" state which causes the attach to hang forever.  Send the
+# process a signal before attaching to wake it up in case this is the case.
+# gdb crashing (yes it does happen) is a common case for processes to be
+# stopped so always deliver this signal before and after attaching.
+sub send_cont_signal {
+    my $pid = shift;
+    kill( "CONT", $pid );
+}
+
  sub fetch_mpi_queue {
      my ( $carg, $vp, $pid ) = @_;
      my $g = gdb_start();
-    kill( "CONT", $pid );
      my $p = gdb_attach( $g, $pid );
      if ( !$p ) {
          debug( $vp, "Failed to attach to process\n" );
@@ -4735,7 +4745,6 @@

          debug $vp, "Attaching to $pid";
          my $gdb = gdb_start();
-        kill( "CONT", $pid );
          if ( gdb_attach( $gdb, $pid ) ) {
              $proc->{gdb} = $gdb;
              push( @all, $proc );
@@ -4778,7 +4787,6 @@

          debug $vp, "Attaching to $pid";
          my $gdb = gdb_start();
-        kill( "CONT", $pid );
          if ( gdb_attach( $gdb, $pid ) ) {
              $proc->{gdb} = $gdb;
              push( @all, $proc );
@@ -5001,6 +5009,7 @@

  sub gdb_read_value {
      my ( $gdb, $name ) = @_;
+
      # Quote the request in case it contains spaces.
      my %t = gdb_n_send( $gdb, "-data-evaluate-expression \"$name\"" );
      if ( $t{status} eq "done" ) {
@@ -5237,7 +5246,7 @@
      debug $vp, "running (p) $cmd";
      my $lines = 0;

-    kill( "CONT", $pid );
+    send_cont_signal($pid);
      open( CMD, "$cmd 2>/dev/null|" )
        || p_die( $vp, "cant start command $cmd" );
      while (<CMD>) {
@@ -5245,7 +5254,7 @@
          output $vp, $_;
          $lines++;
      }
-    kill( "CONT", $pid );
+    send_cont_signal($pid);
      close CMD;
      return $lines;
  }
@@ -5776,7 +5785,6 @@

          debug $vp, "Attaching to $pid";
          my $gdb = gdb_start();
-        kill( "CONT", $pid );
          if ( gdb_attach( $gdb, $pid ) ) {
              $proc->{gdb} = $gdb;
              push( @all, $proc );
@@ -5801,7 +5809,7 @@

              if ($tries) {
                  debug $vp, "Re-attaching to $pid, $tries";
-                kill( "CONT", $pid );
+                send_cont_signal($pid);
                  sleep(1);
                  my $g = gdb_start();
                  if ( gdb_attach( $g, $pid ) ) {
@@ -5824,7 +5832,6 @@
                  }
                  gdb_detach($gdb);
                  gdb_quit($gdb);
-                kill( "CONT", $pid );
                  if ( defined $threads[0]->{frames} ) {
                      my @frames = @{ $threads[0]->{frames} };

@@ -5914,12 +5921,11 @@
      my ( $vp, $pid ) = @_;

      my $gdb = gdb_start();
-    kill( "CONT", $pid );
+
      if ( gdb_attach( $gdb, $pid ) ) {
          my @threads = gdb_dump_frames_per_thread( $gdb, 1 );
          gdb_detach($gdb);
          gdb_quit($gdb);
-        kill( "CONT", $pid );

          foreach my $thread ( sort { $a->{id} <=> $b->{id} } @threads ) {
              my @frames = @{ $thread->{frames} };
@@ -6061,7 +6067,6 @@
          my $vp  = $proc->{vp};
          my $pid = $proc->{pid};
          my $gdb = gdb_start();
-        kill( "CONT", $pid );
          if ( gdb_attach( $gdb, $pid ) ) {
              $proc->{gdb} = $gdb;
          } else {