Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 208 insertions, 0 deletions

diff --git a/xpcom/base/MemoryMapping.cpp b/xpcom/base/MemoryMapping.cpp
new file mode 100644
index 0000000000..1ec1cf1f61
--- /dev/null
+++ b/xpcom/base/MemoryMapping.cpp
@@ -0,0 +1,208 @@
+/* -*- 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/. */
+
+#include "mozilla/MemoryMapping.h"
+
+#include "mozilla/BinarySearch.h"
+#include "mozilla/FileUtils.h"
+
+#include <fstream>
+#include <string>
+#include <sstream>
+
+namespace mozilla {
+
+namespace {
+struct VMFlagString {
+  const char* mName;
+  const char* mPrettyName;
+  VMFlag mFlag;
+};
+
+static const VMFlagString sVMFlagStrings[] = {
+    // clang-format off
+  {"ac", "Accountable",   VMFlag::Accountable},
+  {"ar", "ArchSpecific",  VMFlag::ArchSpecific},
+  {"dc", "NoFork",        VMFlag::NoFork},
+  {"dd", "NoCore",        VMFlag::NoCore},
+  {"de", "NoExpand",      VMFlag::NoExpand},
+  {"dw", "DisabledWrite", VMFlag::DisabledWrite},
+  {"ex", "Executable",    VMFlag::Executable},
+  {"gd", "GrowsDown",     VMFlag::GrowsDown},
+  {"hg", "HugePage",      VMFlag::HugePage},
+  {"ht", "HugeTLB",       VMFlag::HugeTLB},
+  {"io", "IO",            VMFlag::IO},
+  {"lo", "Locked",        VMFlag::Locked},
+  {"me", "MayExecute",    VMFlag::MayExecute},
+  {"mg", "Mergeable",     VMFlag::Mergeable},
+  {"mm", "MixedMap",      VMFlag::MixedMap},
+  {"mr", "MayRead",       VMFlag::MayRead},
+  {"ms", "MayShare",      VMFlag::MayShare},
+  {"mw", "MayWrite",      VMFlag::MayWrite},
+  {"nh", "NoHugePage",    VMFlag::NoHugePage},
+  {"nl", "NonLinear",     VMFlag::NonLinear},
+  {"nr", "NotReserved",   VMFlag::NotReserved},
+  {"pf", "PurePFN",       VMFlag::PurePFN},
+  {"rd", "Readable",      VMFlag::Readable},
+  {"rr", "Random",        VMFlag::Random},
+  {"sd", "SoftDirty",     VMFlag::SoftDirty},
+  {"sh", "Shared",        VMFlag::Shared},
+  {"sr", "Sequential",    VMFlag::Sequential},
+  {"wr", "Writable",      VMFlag::Writable},
+    // clang-format on
+};
+}  // anonymous namespace
+
+constexpr size_t kVMFlags = size_t(-1);
+
+// An array of known field names which may be present in an smaps file, and the
+// offsets of the corresponding fields in a MemoryMapping class.
+const MemoryMapping::Field MemoryMapping::sFields[] = {
+    // clang-format off
+  {"AnonHugePages",   offsetof(MemoryMapping, mAnonHugePages)},
+  {"Anonymous",       offsetof(MemoryMapping, mAnonymous)},
+  {"KernelPageSize",  offsetof(MemoryMapping, mKernelPageSize)},
+  {"LazyFree",        offsetof(MemoryMapping, mLazyFree)},
+  {"Locked",          offsetof(MemoryMapping, mLocked)},
+  {"MMUPageSize",     offsetof(MemoryMapping, mMMUPageSize)},
+  {"Private_Clean",   offsetof(MemoryMapping, mPrivate_Clean)},
+  {"Private_Dirty",   offsetof(MemoryMapping, mPrivate_Dirty)},
+  {"Private_Hugetlb", offsetof(MemoryMapping, mPrivate_Hugetlb)},
+  {"Pss",             offsetof(MemoryMapping, mPss)},
+  {"Referenced",      offsetof(MemoryMapping, mReferenced)},
+  {"Rss",             offsetof(MemoryMapping, mRss)},
+  {"Shared_Clean",    offsetof(MemoryMapping, mShared_Clean)},
+  {"Shared_Dirty",    offsetof(MemoryMapping, mShared_Dirty)},
+  {"Shared_Hugetlb",  offsetof(MemoryMapping, mShared_Hugetlb)},
+  {"ShmemPmdMapped",  offsetof(MemoryMapping, mShmemPmdMapped)},
+  {"Size",            offsetof(MemoryMapping, mSize)},
+  {"Swap",            offsetof(MemoryMapping, mSwap)},
+  {"SwapPss",         offsetof(MemoryMapping, mSwapPss)},
+  // VmFlags is a special case. It contains an array of flag strings, which
+  // describe attributes of the mapping, rather than a mapping size. We include
+  // it in this array to aid in parsing, but give it a separate sentinel value,
+  // and treat it specially.
+  {"VmFlags",         kVMFlags},
+    // clang-format on
+};
+
+template <typename T, int n>
+const T* FindEntry(const char* aName, const T (&aEntries)[n]) {
+  size_t index;
+  if (BinarySearchIf(
+          aEntries, 0, n,
+          [&](const T& aEntry) { return strcmp(aName, aEntry.mName); },
+          &index)) {
+    return &aEntries[index];
+  }
+  return nullptr;
+}
+
+using Perm = MemoryMapping::Perm;
+using PermSet = MemoryMapping::PermSet;
+
+nsresult GetMemoryMappings(nsTArray<MemoryMapping>& aMappings, pid_t aPid) {
+  std::ifstream stream;
+  if (aPid == 0) {
+    stream.open("/proc/self/smaps");
+  } else {
+    std::ostringstream path;
+    path << "/proc/" << aPid << "/smaps" << std::ends;
+    stream.open(path.str());
+  }
+  if (stream.fail()) {
+    return NS_ERROR_FAILURE;
+  }
+
+  MemoryMapping* current = nullptr;
+  std::string buffer;
+  while (std::getline(stream, buffer)) {
+    size_t start, end, offset;
+    char flags[4] = "---";
+    char name[512];
+
+    name[0] = 0;
+
+    // clang-format off
+    // Match the start of an entry. A typical line looks something like:
+    //
+    // 1487118a7000-148711a5a000 r-xp 00000000 103:03 54004561                  /usr/lib/libc-2.27.so
+    // clang-format on
+    if (sscanf(buffer.c_str(), "%zx-%zx %4c %zx %*u:%*u %*u %511s\n", &start,
+               &end, flags, &offset, name) >= 4) {
+      PermSet perms;
+      if (flags[0] == 'r') {
+        perms += Perm::Read;
+      }
+      if (flags[1] == 'w') {
+        perms += Perm::Write;
+      }
+      if (flags[2] == 'x') {
+        perms += Perm::Execute;
+      }
+      if (flags[3] == 'p') {
+        perms += Perm::Private;
+      } else if (flags[3] == 's') {
+        perms += Perm::Shared;
+      }
+
+      current = aMappings.AppendElement(
+          MemoryMapping{start, end, perms, offset, name});
+      continue;
+    }
+    if (!current) {
+      continue;
+    }
+
+    nsAutoCStringN<128> line(buffer.c_str());
+    char* savePtr;
+    char* fieldName = strtok_r(line.BeginWriting(), ":", &savePtr);
+    if (!fieldName) {
+      continue;
+    }
+    auto* field = FindEntry(fieldName, MemoryMapping::sFields);
+    if (!field) {
+      continue;
+    }
+
+    if (field->mOffset == kVMFlags) {
+      while (char* flagName = strtok_r(nullptr, " \n", &savePtr)) {
+        if (auto* flag = FindEntry(flagName, sVMFlagStrings)) {
+          current->mFlags += flag->mFlag;
+        }
+      }
+      continue;
+    }
+
+    const char* rest = strtok_r(nullptr, "\n", &savePtr);
+    size_t value;
+    if (sscanf(rest, "%zd kB", &value) > 0) {
+      current->ValueForField(*field) = value * 1024;
+    }
+  }
+
+  return NS_OK;
+}
+
+void MemoryMapping::Dump(nsACString& aOut) const {
+  aOut.AppendPrintf("%zx-%zx Size: %zu Offset: %zx %s\n", mStart, mEnd,
+                    mEnd - mStart, mOffset, mName.get());
+
+  for (auto& field : MemoryMapping::sFields) {
+    if (field.mOffset < sizeof(*this)) {
+      aOut.AppendPrintf("  %s: %zd\n", field.mName, ValueForField(field));
+    }
+  }
+
+  aOut.AppendPrintf("  Flags: %x\n", mFlags.serialize());
+  for (auto& flag : sVMFlagStrings) {
+    if (mFlags.contains(flag.mFlag)) {
+      aOut.AppendPrintf("       : %s %s\n", flag.mName, flag.mPrettyName);
+    }
+  }
+}
+
+}  // namespace mozilla