1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/memory/mozalloc/mozalloc_oom.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,57 @@
1.4 +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
1.5 + * vim: sw=4 ts=4 et :
1.6 + */
1.7 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.8 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.9 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.10 +
1.11 +#if defined(XP_WIN)
1.12 +# define MOZALLOC_EXPORT __declspec(dllexport)
1.13 +#endif
1.14 +
1.15 +#include "mozilla/mozalloc_abort.h"
1.16 +#include "mozilla/mozalloc_oom.h"
1.17 +#include "mozilla/Assertions.h"
1.18 +
1.19 +static mozalloc_oom_abort_handler gAbortHandler;
1.20 +
1.21 +#define OOM_MSG_LEADER "out of memory: 0x"
1.22 +#define OOM_MSG_DIGITS "0000000000000000" // large enough for 2^64
1.23 +#define OOM_MSG_TRAILER " bytes requested"
1.24 +#define OOM_MSG_FIRST_DIGIT_OFFSET sizeof(OOM_MSG_LEADER) - 1
1.25 +#define OOM_MSG_LAST_DIGIT_OFFSET sizeof(OOM_MSG_LEADER) + \
1.26 + sizeof(OOM_MSG_DIGITS) - 3
1.27 +
1.28 +static const char *hex = "0123456789ABCDEF";
1.29 +
1.30 +void
1.31 +mozalloc_handle_oom(size_t size)
1.32 +{
1.33 + char oomMsg[] = OOM_MSG_LEADER OOM_MSG_DIGITS OOM_MSG_TRAILER;
1.34 + size_t i;
1.35 +
1.36 + // NB: this is handle_oom() stage 1, which simply aborts on OOM.
1.37 + // we might proceed to a stage 2 in which an attempt is made to
1.38 + // reclaim memory
1.39 +
1.40 + if (gAbortHandler)
1.41 + gAbortHandler(size);
1.42 +
1.43 + static_assert(OOM_MSG_FIRST_DIGIT_OFFSET > 0,
1.44 + "Loop below will never terminate (i can't go below 0)");
1.45 +
1.46 + // Insert size into the diagnostic message using only primitive operations
1.47 + for (i = OOM_MSG_LAST_DIGIT_OFFSET;
1.48 + size && i >= OOM_MSG_FIRST_DIGIT_OFFSET; i--) {
1.49 + oomMsg[i] = hex[size % 16];
1.50 + size /= 16;
1.51 + }
1.52 +
1.53 + mozalloc_abort(oomMsg);
1.54 +}
1.55 +
1.56 +void
1.57 +mozalloc_set_oom_abort_handler(mozalloc_oom_abort_handler handler)
1.58 +{
1.59 + gAbortHandler = handler;
1.60 +}
