From 26a029d407be480d791972afb5975cf62c9360a6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 19 Apr 2024 02:47:55 +0200 Subject: Adding upstream version 124.0.1. Signed-off-by: Daniel Baumann --- xpcom/base/AvailableMemoryWatcherUtils.h | 56 ++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 xpcom/base/AvailableMemoryWatcherUtils.h (limited to 'xpcom/base/AvailableMemoryWatcherUtils.h') diff --git a/xpcom/base/AvailableMemoryWatcherUtils.h b/xpcom/base/AvailableMemoryWatcherUtils.h new file mode 100644 index 0000000000..2d70fe5fd0 --- /dev/null +++ b/xpcom/base/AvailableMemoryWatcherUtils.h @@ -0,0 +1,56 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_AvailableMemoryWatcherUtils_h +#define mozilla_AvailableMemoryWatcherUtils_h + +#include "mozilla/Attributes.h" +#include "nsISupportsUtils.h" // For nsresult + +namespace mozilla { + +struct MemoryInfo { + unsigned long memTotal; + unsigned long memAvailable; +}; +// Check /proc/meminfo for low memory. Largely C method for reading +// /proc/meminfo. +MOZ_MAYBE_UNUSED +static nsresult ReadMemoryFile(const char* meminfoPath, MemoryInfo& aResult) { + FILE* fd; + if ((fd = fopen(meminfoPath, "r")) == nullptr) { + // Meminfo somehow unreachable + return NS_ERROR_FAILURE; + } + + char buff[128]; + + /* The first few lines of meminfo look something like this: + * MemTotal: 65663448 kB + * MemFree: 57368112 kB + * MemAvailable: 61852700 kB + * We mostly care about the available versus the total. We calculate our + * memory thresholds using this, and when memory drops below 5% we consider + * this to be a memory pressure event. In practice these lines aren't + * necessarily in order, but we can simply search for MemTotal + * and MemAvailable. + */ + char namebuffer[20]; + while ((fgets(buff, sizeof(buff), fd)) != nullptr) { + if (strstr(buff, "MemTotal:")) { + sscanf(buff, "%s %lu ", namebuffer, &aResult.memTotal); + } + if (strstr(buff, "MemAvailable:")) { + sscanf(buff, "%s %lu ", namebuffer, &aResult.memAvailable); + } + } + fclose(fd); + return NS_OK; +} + +} // namespace mozilla + +#endif // ifndef mozilla_AvailableMemoryWatcherUtils_h -- cgit v1.2.3