http/pprof: fix POST reading bug
R=bradfitz
CC=golang-dev
https://golang.org/cl/4430075
diff --git a/src/cmd/prof/gopprof b/src/cmd/prof/gopprof
index 8fa00cb..8863fc6 100755
--- a/src/cmd/prof/gopprof
+++ b/src/cmd/prof/gopprof
@@ -2880,17 +2880,18 @@
my @toask = @pcs;
while (@toask > 0) {
my $n = @toask;
- if ($n > 49) { $n = 49; }
+ # NOTE(rsc): Limiting the number of PCs requested per round
+ # used to be necessary, but I think it was a bug in
+ # debug/pprof/symbol's implementation. Leaving here
+ # in case I am wrong.
+ # if ($n > 49) { $n = 49; }
my @thisround = @toask[0..$n];
-my $t = @toask;
-print STDERR "$n $t\n";
@toask = @toask[($n+1)..(@toask-1)];
my $post_data = join("+", sort((map {"0x" . "$_"} @thisround)));
open(POSTFILE, ">$main::tmpfile_sym");
print POSTFILE $post_data;
close(POSTFILE);
-print STDERR "SYMBL!\n";
my $url = SymbolPageURL();
$url = ResolveRedirectionForCurl($url);
my $command_line = "$CURL -sd '\@$main::tmpfile_sym' '$url'";
diff --git a/src/pkg/http/pprof/pprof.go b/src/pkg/http/pprof/pprof.go
index bc79e21..917c7f8 100644
--- a/src/pkg/http/pprof/pprof.go
+++ b/src/pkg/http/pprof/pprof.go
@@ -26,6 +26,7 @@
import (
"bufio"
+ "bytes"
"fmt"
"http"
"os"
@@ -88,10 +89,14 @@
func Symbol(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+ // We have to read the whole POST body before
+ // writing any output. Buffer the output here.
+ var buf bytes.Buffer
+
// We don't know how many symbols we have, but we
// do have symbol information. Pprof only cares whether
// this number is 0 (no symbols available) or > 0.
- fmt.Fprintf(w, "num_symbols: 1\n")
+ fmt.Fprintf(&buf, "num_symbols: 1\n")
var b *bufio.Reader
if r.Method == "POST" {
@@ -109,14 +114,19 @@
if pc != 0 {
f := runtime.FuncForPC(uintptr(pc))
if f != nil {
- fmt.Fprintf(w, "%#x %s\n", pc, f.Name())
+ fmt.Fprintf(&buf, "%#x %s\n", pc, f.Name())
}
}
// Wait until here to check for err; the last
// symbol will have an err because it doesn't end in +.
if err != nil {
+ if err != os.EOF {
+ fmt.Fprintf(&buf, "reading request: %v\n", err)
+ }
break
}
}
+
+ w.Write(buf.Bytes())
}
