X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit.git;a=blobdiff_plain;f=dgit;h=59fabafb5672de394b66ca3d333ae53214a8466c;hp=b24264676f23de3e67c5a78592c51b7d6c921982;hb=f0e2a4873a21f9b0399686aad295938891dc5417;hpb=0ebf9dfcc7a8c45e3b8b2db4a711b7deeff7f8bc

diff --git a/dgit b/dgit
index b2426467..59fabafb 100755
--- a/dgit
+++ b/dgit
@@ -30,6 +30,7 @@ use Dpkg::Version;
 use POSIX;
 use IPC::Open2;
 use Digest::SHA;
+use Config;
 
 our $our_version = 'UNRELEASED'; ###substituted###
 
@@ -133,6 +134,23 @@ END {
     }
 };
 
+our @signames = split / /, $Config{sig_name};
+
+sub waitstatusmsg () {
+    if (!$?) {
+	return "terminated, reporting successful completion";
+    } elsif (!($? & 255)) {
+	return "failed with error exit status ".WEXITSTATUS($?);
+    } elsif (WIFSIGNALED($?)) {
+	my $signum=WTERMSIG($?);
+	return "died due to fatal signal ".
+	    ($signames[$signum] // "number $signum").
+	    ($? & 128 ? " (core dumped)" : ""); # POSIX(3pm) has no WCOREDUMP
+    } else {
+	return "failed with unknown wait status ".$?;
+    }
+}
+
 sub printdebug { print DEBUG $debugprefix, @_ or die $!; }
 
 sub fail { 
@@ -194,17 +212,39 @@ sub changedir ($) {
 #
 #  > complete
 
+our $i_child_pid;
+
+sub i_child_report () {
+    # Sees if our child has died, and reap it if so.  Returns a string
+    # describing how it died if it failed, or undef otherwise.
+    return undef unless $i_child_pid;
+    my $got = waitpid $i_child_pid, WNOHANG;
+    return undef if $got <= 0;
+    die unless $got == $i_child_pid;
+    $i_child_pid = undef;
+    return undef unless $?;
+    return "build host child ".waitstatusmsg();
+}
+
 sub badproto ($$) {
     my ($fh, $m) = @_;
     fail "connection lost: $!" if $fh->error;
     fail "protocol violation; $m not expected";
 }
 
+sub badproto_badread ($$) {
+    my ($fh, $wh) = @_;
+    fail "connection lost: $!" if $!;
+    my $report = i_child_report();
+    fail $report if defined $report;
+    badproto $fh, "eof (reading $wh)";
+}
+
 sub protocol_expect (&$) {
     my ($match, $fh) = @_;
     local $_;
     $_ = <$fh>;
-    defined && chomp or badproto $fh, "eof";
+    defined && chomp or badproto_badread $fh, "protocol message";
     if (wantarray) {
 	my @r = &$match;
 	return @r if @r;
@@ -236,7 +276,7 @@ sub protocol_read_bytes ($$) {
     $nbytes =~ m/^[1-9]\d{0,5}$/ or badproto \*RO, "bad byte count";
     my $d;
     my $got = read $fh, $d, $nbytes;
-    $got==$nbytes or badproto $fh, "eof during data block";
+    $got==$nbytes or badproto_badread $fh, "data block";
     return $d;
 }
 
@@ -350,10 +390,8 @@ sub failedcmd {
     { local ($!); printcmd \*STDERR, "$us: failed command:", @_ or die $!; };
     if ($!) {
 	fail "failed to fork/exec: $!";
-    } elsif (!($? & 0xff)) {
-	fail "subprocess failed with error exit status ".($?>>8);
     } elsif ($?) {
-	fail "subprocess crashed (wait status $?)";
+	fail "subprocess ".waitstatusmsg();
     } else {
 	fail "subprocess produced invalid output";
     }
@@ -1781,10 +1819,10 @@ sub i_resp_progress ($) {
 sub i_resp_complete {
     my $pid = $i_child_pid;
     $i_child_pid = undef; # prevents killing some other process with same pid
-    printdebug "waiting for remote child $pid...\n";
+    printdebug "waiting for build host child $pid...\n";
     my $got = waitpid $pid, 0;
     die $! unless $got == $pid;
-    die "remote child failed $?" if $?;
+    die "build host child failed $?" if $?;
 
     i_cleanup();
     printdebug "all done\n";