--- a/hotspot/src/share/vm/utilities/ostream.cpp Wed Jan 27 22:39:03 2016 -0500
+++ b/hotspot/src/share/vm/utilities/ostream.cpp Thu Jan 28 07:11:45 2016 +0100
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -44,6 +44,8 @@
_newlines = 0;
_precount = 0;
_indentation = 0;
+ _scratch = NULL;
+ _scratch_len = 0;
}
outputStream::outputStream(int width, bool has_time_stamps) {
@@ -52,6 +54,8 @@
_newlines = 0;
_precount = 0;
_indentation = 0;
+ _scratch = NULL;
+ _scratch_len = 0;
if (has_time_stamps) _stamp.update();
}
@@ -119,38 +123,47 @@
return result;
}
+void outputStream::do_vsnprintf_and_write_with_automatic_buffer(const char* format, va_list ap, bool add_cr) {
+ char buffer[O_BUFLEN];
+ size_t len;
+ const char* str = do_vsnprintf(buffer, sizeof(buffer), format, ap, add_cr, len);
+ write(str, len);
+}
+
+void outputStream::do_vsnprintf_and_write_with_scratch_buffer(const char* format, va_list ap, bool add_cr) {
+ size_t len;
+ const char* str = do_vsnprintf(_scratch, _scratch_len, format, ap, add_cr, len);
+ write(str, len);
+}
+
+void outputStream::do_vsnprintf_and_write(const char* format, va_list ap, bool add_cr) {
+ if (_scratch) {
+ do_vsnprintf_and_write_with_scratch_buffer(format, ap, add_cr);
+ } else {
+ do_vsnprintf_and_write_with_automatic_buffer(format, ap, add_cr);
+ }
+}
+
void outputStream::print(const char* format, ...) {
- char buffer[O_BUFLEN];
va_list ap;
va_start(ap, format);
- size_t len;
- const char* str = do_vsnprintf(buffer, O_BUFLEN, format, ap, false, len);
- write(str, len);
+ do_vsnprintf_and_write(format, ap, false);
va_end(ap);
}
void outputStream::print_cr(const char* format, ...) {
- char buffer[O_BUFLEN];
va_list ap;
va_start(ap, format);
- size_t len;
- const char* str = do_vsnprintf(buffer, O_BUFLEN, format, ap, true, len);
- write(str, len);
+ do_vsnprintf_and_write(format, ap, true);
va_end(ap);
}
void outputStream::vprint(const char *format, va_list argptr) {
- char buffer[O_BUFLEN];
- size_t len;
- const char* str = do_vsnprintf(buffer, O_BUFLEN, format, argptr, false, len);
- write(str, len);
+ do_vsnprintf_and_write(format, argptr, false);
}
void outputStream::vprint_cr(const char* format, va_list argptr) {
- char buffer[O_BUFLEN];
- size_t len;
- const char* str = do_vsnprintf(buffer, O_BUFLEN, format, argptr, true, len);
- write(str, len);
+ do_vsnprintf_and_write(format, argptr, true);
}
void outputStream::fill_to(int col) {
@@ -958,53 +971,6 @@
}
}
-staticBufferStream::staticBufferStream(char* buffer, size_t buflen,
- outputStream *outer_stream) {
- _buffer = buffer;
- _buflen = buflen;
- _outer_stream = outer_stream;
- // compile task prints time stamp relative to VM start
- _stamp.update_to(1);
-}
-
-void staticBufferStream::write(const char* c, size_t len) {
- _outer_stream->print_raw(c, (int)len);
-}
-
-void staticBufferStream::flush() {
- _outer_stream->flush();
-}
-
-void staticBufferStream::print(const char* format, ...) {
- va_list ap;
- va_start(ap, format);
- size_t len;
- const char* str = do_vsnprintf(_buffer, _buflen, format, ap, false, len);
- write(str, len);
- va_end(ap);
-}
-
-void staticBufferStream::print_cr(const char* format, ...) {
- va_list ap;
- va_start(ap, format);
- size_t len;
- const char* str = do_vsnprintf(_buffer, _buflen, format, ap, true, len);
- write(str, len);
- va_end(ap);
-}
-
-void staticBufferStream::vprint(const char *format, va_list argptr) {
- size_t len;
- const char* str = do_vsnprintf(_buffer, _buflen, format, argptr, false, len);
- write(str, len);
-}
-
-void staticBufferStream::vprint_cr(const char* format, va_list argptr) {
- size_t len;
- const char* str = do_vsnprintf(_buffer, _buflen, format, argptr, true, len);
- write(str, len);
-}
-
bufferedStream::bufferedStream(size_t initial_size, size_t bufmax) : outputStream() {
buffer_length = initial_size;
buffer = NEW_C_HEAP_ARRAY(char, buffer_length, mtInternal);
--- a/hotspot/src/share/vm/utilities/ostream.hpp Wed Jan 27 22:39:03 2016 -0500
+++ b/hotspot/src/share/vm/utilities/ostream.hpp Thu Jan 28 07:11:45 2016 +0100
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -49,6 +49,8 @@
int _newlines; // number of '\n' output so far
julong _precount; // number of chars output, less _position
TimeStamp _stamp; // for time stamps
+ char* _scratch; // internal scratch buffer for printf
+ size_t _scratch_len; // size of internal scratch buffer
void update_position(const char* s, size_t len);
static const char* do_vsnprintf(char* buffer, size_t buflen,
@@ -56,6 +58,13 @@
bool add_cr,
size_t& result_len) ATTRIBUTE_PRINTF(3, 0);
+ // calls do_vsnprintf and writes output to stream; uses an on-stack buffer.
+ void do_vsnprintf_and_write_with_automatic_buffer(const char* format, va_list ap, bool add_cr) ATTRIBUTE_PRINTF(2, 0);
+ // calls do_vsnprintf and writes output to stream; uses the user-provided buffer;
+ void do_vsnprintf_and_write_with_scratch_buffer(const char* format, va_list ap, bool add_cr) ATTRIBUTE_PRINTF(2, 0);
+ // calls do_vsnprintf, then writes output to stream.
+ void do_vsnprintf_and_write(const char* format, va_list ap, bool add_cr) ATTRIBUTE_PRINTF(2, 0);
+
public:
// creation
outputStream(int width = 80);
@@ -119,6 +128,10 @@
virtual void rotate_log(bool force, outputStream* out = NULL) {} // GC log rotation
virtual ~outputStream() {} // close properly on deletion
+ // Caller may specify their own scratch buffer to use for printing; otherwise,
+ // an automatic buffer on the stack (with O_BUFLEN len) is used.
+ void set_scratch_buffer(char* p, size_t len) { _scratch = p; _scratch_len = len; }
+
void dec_cr() { dec(); cr(); }
void inc_cr() { inc(); cr(); }
};
@@ -250,26 +263,6 @@
void ostream_exit();
void ostream_abort();
-// staticBufferStream uses a user-supplied buffer for all formatting.
-// Used for safe formatting during fatal error handling. Not MT safe.
-// Do not share the stream between multiple threads.
-class staticBufferStream : public outputStream {
- private:
- char* _buffer;
- size_t _buflen;
- outputStream* _outer_stream;
- public:
- staticBufferStream(char* buffer, size_t buflen,
- outputStream *outer_stream);
- ~staticBufferStream() {};
- virtual void write(const char* c, size_t len);
- void flush();
- void print(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
- void print_cr(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
- void vprint(const char *format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
- void vprint_cr(const char* format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
-};
-
// In the non-fixed buffer case an underlying buffer will be created and
// managed in C heap. Not MT-safe.
class bufferedStream : public outputStream {
--- a/hotspot/src/share/vm/utilities/vmError.cpp Wed Jan 27 22:39:03 2016 -0500
+++ b/hotspot/src/share/vm/utilities/vmError.cpp Thu Jan 28 07:11:45 2016 +0100
@@ -987,10 +987,12 @@
volatile intptr_t VMError::first_error_tid = -1;
// An error could happen before tty is initialized or after it has been
-// destroyed. Here we use a very simple unbuffered fdStream for printing.
-// Only out.print_raw() and out.print_raw_cr() should be used, as other
-// printing methods need to allocate large buffer on stack. To format a
-// string, use jio_snprintf() with a static buffer or use staticBufferStream.
+// destroyed.
+// Please note: to prevent large stack allocations, the log- and
+// output-stream use a global scratch buffer for format printing.
+// (see VmError::report_and_die(). Access to those streams is synchronized
+// in VmError::report_and_die() - there is only one reporting thread at
+// any given time.
fdStream VMError::out(defaultStream::output_fd());
fdStream VMError::log; // error log used by VMError::report_and_die()
@@ -1100,6 +1102,8 @@
{
// Don't allocate large buffer on stack
static char buffer[O_BUFLEN];
+ out.set_scratch_buffer(buffer, sizeof(buffer));
+ log.set_scratch_buffer(buffer, sizeof(buffer));
// How many errors occurred in error handler when reporting first_error.
static int recursive_error_count;
@@ -1186,8 +1190,7 @@
// print to screen
if (!out_done) {
- staticBufferStream sbs(buffer, sizeof(buffer), &out);
- report(&sbs, false);
+ report(&out, false);
out_done = true;
@@ -1215,8 +1218,7 @@
}
}
- staticBufferStream sbs(buffer, O_BUFLEN, &log);
- report(&sbs, true);
+ report(&log, true);
_current_step = 0;
_current_step_info = "";