Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

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

1 files changed, 234 insertions, 0 deletions

diff --git a/js/public/Stack.h b/js/public/Stack.h
new file mode 100644
index 0000000000..6f01b2b728
--- /dev/null
+++ b/js/public/Stack.h
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+/* -*- 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 js_Stack_h
+#define js_Stack_h
+
+#include "mozilla/Assertions.h"  // MOZ_ASSERT
+#include "mozilla/Maybe.h"       // mozilla::Maybe
+#include "mozilla/Variant.h"     // mozilla::Variant
+
+#include <stddef.h>  // size_t
+#include <stdint.h>  // uint32_t, uintptr_t, UINTPTR_MAX
+#include <utility>   // std::move
+
+#include "jstypes.h"  // JS_PUBLIC_API
+
+#include "js/Principals.h"  // JSPrincipals, JS_HoldPrincipals, JS_DropPrincipals
+#include "js/TypeDecls.h"   // JSContext, Handle*, MutableHandle*
+
+namespace JS {
+
+using NativeStackSize = size_t;
+
+using NativeStackBase = uintptr_t;
+
+using NativeStackLimit = uintptr_t;
+
+#if JS_STACK_GROWTH_DIRECTION > 0
+constexpr NativeStackLimit NativeStackLimitMin = 0;
+constexpr NativeStackLimit NativeStackLimitMax = UINTPTR_MAX;
+#else
+constexpr NativeStackLimit NativeStackLimitMin = UINTPTR_MAX;
+constexpr NativeStackLimit NativeStackLimitMax = 0;
+#endif
+
+#ifdef __wasi__
+// We build with the "stack-first" wasm-ld option, so the stack grows downward
+// toward zero. Let's set a limit just a bit above this so that we catch an
+// overflow before a Wasm trap occurs.
+constexpr NativeStackLimit WASINativeStackLimit = 1024;
+#endif  // __wasi__
+
+inline NativeStackLimit GetNativeStackLimit(NativeStackBase base,
+                                            NativeStackSize size) {
+#if JS_STACK_GROWTH_DIRECTION > 0
+  MOZ_ASSERT(base <= size_t(-1) - size);
+  return base + size - 1;
+#else   // stack grows up
+  MOZ_ASSERT(base >= size);
+  return base - (size - 1);
+#endif  // stack grows down
+}
+
+}  // namespace JS
+
+/**
+ * Set the size of the native stack that should not be exceed. To disable
+ * stack size checking pass 0.
+ *
+ * SpiderMonkey allows for a distinction between system code (such as GCs, which
+ * may incidentally be triggered by script but are not strictly performed on
+ * behalf of such script), trusted script (as determined by
+ * JS_SetTrustedPrincipals), and untrusted script. Each kind of code may have a
+ * different stack quota, allowing embedders to keep higher-priority machinery
+ * running in the face of scripted stack exhaustion by something else.
+ *
+ * The stack quotas for each kind of code should be monotonically descending,
+ * and may be specified with this function. If 0 is passed for a given kind
+ * of code, it defaults to the value of the next-highest-priority kind.
+ *
+ * This function may only be called immediately after the runtime is initialized
+ * and before any code is executed and/or interrupts requested.
+ */
+extern JS_PUBLIC_API void JS_SetNativeStackQuota(
+    JSContext* cx, JS::NativeStackSize systemCodeStackSize,
+    JS::NativeStackSize trustedScriptStackSize = 0,
+    JS::NativeStackSize untrustedScriptStackSize = 0);
+
+namespace js {
+
+enum class StackFormat { SpiderMonkey, V8, Default };
+
+/*
+ * Sets the format used for stringifying Error stacks.
+ *
+ * The default format is StackFormat::SpiderMonkey.  Use StackFormat::V8
+ * in order to emulate V8's stack formatting.  StackFormat::Default can't be
+ * used here.
+ */
+extern JS_PUBLIC_API void SetStackFormat(JSContext* cx, StackFormat format);
+
+extern JS_PUBLIC_API StackFormat GetStackFormat(JSContext* cx);
+
+}  // namespace js
+
+namespace JS {
+
+/**
+ * Capture all frames.
+ */
+struct AllFrames {};
+
+/**
+ * Capture at most this many frames.
+ */
+struct MaxFrames {
+  uint32_t maxFrames;
+
+  explicit MaxFrames(uint32_t max) : maxFrames(max) { MOZ_ASSERT(max > 0); }
+};
+
+/**
+ * Capture the first frame with the given principals. By default, do not
+ * consider self-hosted frames with the given principals as satisfying the stack
+ * capture.
+ */
+struct JS_PUBLIC_API FirstSubsumedFrame {
+  JSContext* cx;
+  JSPrincipals* principals;
+  bool ignoreSelfHosted;
+
+  /**
+   * Use the cx's current compartment's principals.
+   */
+  explicit FirstSubsumedFrame(JSContext* cx,
+                              bool ignoreSelfHostedFrames = true);
+
+  explicit FirstSubsumedFrame(JSContext* ctx, JSPrincipals* p,
+                              bool ignoreSelfHostedFrames = true)
+      : cx(ctx), principals(p), ignoreSelfHosted(ignoreSelfHostedFrames) {
+    if (principals) {
+      JS_HoldPrincipals(principals);
+    }
+  }
+
+  // No copying because we want to avoid holding and dropping principals
+  // unnecessarily.
+  FirstSubsumedFrame(const FirstSubsumedFrame&) = delete;
+  FirstSubsumedFrame& operator=(const FirstSubsumedFrame&) = delete;
+
+  FirstSubsumedFrame(FirstSubsumedFrame&& rhs)
+      : principals(rhs.principals), ignoreSelfHosted(rhs.ignoreSelfHosted) {
+    MOZ_ASSERT(this != &rhs, "self move disallowed");
+    rhs.principals = nullptr;
+  }
+
+  FirstSubsumedFrame& operator=(FirstSubsumedFrame&& rhs) {
+    new (this) FirstSubsumedFrame(std::move(rhs));
+    return *this;
+  }
+
+  ~FirstSubsumedFrame() {
+    if (principals) {
+      JS_DropPrincipals(cx, principals);
+    }
+  }
+};
+
+using StackCapture = mozilla::Variant<AllFrames, MaxFrames, FirstSubsumedFrame>;
+
+/**
+ * Capture the current call stack as a chain of SavedFrame JSObjects, and set
+ * |stackp| to the SavedFrame for the youngest stack frame, or nullptr if there
+ * are no JS frames on the stack.
+ *
+ * The |capture| parameter describes the portion of the JS stack to capture:
+ *
+ *   * |JS::AllFrames|: Capture all frames on the stack.
+ *
+ *   * |JS::MaxFrames|: Capture no more than |JS::MaxFrames::maxFrames| from the
+ *      stack.
+ *
+ *   * |JS::FirstSubsumedFrame|: Capture the first frame whose principals are
+ *     subsumed by |JS::FirstSubsumedFrame::principals|. By default, do not
+ *     consider self-hosted frames; this can be controlled via the
+ *     |JS::FirstSubsumedFrame::ignoreSelfHosted| flag. Do not capture any async
+ *     stack.
+ */
+extern JS_PUBLIC_API bool CaptureCurrentStack(
+    JSContext* cx, MutableHandleObject stackp,
+    StackCapture&& capture = StackCapture(AllFrames()));
+
+/**
+ * Returns true if capturing stack trace data to associate with an asynchronous
+ * operation is currently enabled for the current context realm.
+ *
+ * Users should check this state before capturing a stack that will be passed
+ * back to AutoSetAsyncStackForNewCalls later, in order to avoid capturing a
+ * stack for async use when we don't actually want to capture it.
+ */
+extern JS_PUBLIC_API bool IsAsyncStackCaptureEnabledForRealm(JSContext* cx);
+
+/*
+ * This is a utility function for preparing an async stack to be used
+ * by some other object.  This may be used when you need to treat a
+ * given stack trace as an async parent.  If you just need to capture
+ * the current stack, async parents and all, use CaptureCurrentStack
+ * instead.
+ *
+ * Here |asyncStack| is the async stack to prepare.  It is copied into
+ * |cx|'s current compartment, and the newest frame is given
+ * |asyncCause| as its asynchronous cause.  If |maxFrameCount| is
+ * |Some(n)|, capture at most the youngest |n| frames.  The
+ * new stack object is written to |stackp|.  Returns true on success,
+ * or sets an exception and returns |false| on error.
+ */
+extern JS_PUBLIC_API bool CopyAsyncStack(
+    JSContext* cx, HandleObject asyncStack, HandleString asyncCause,
+    MutableHandleObject stackp, const mozilla::Maybe<size_t>& maxFrameCount);
+
+/**
+ * Given a SavedFrame JSObject stack, stringify it in the same format as
+ * Error.prototype.stack. The stringified stack out parameter is placed in the
+ * cx's compartment. Defaults to the empty string.
+ *
+ * The same notes above about SavedFrame accessors applies here as well: cx
+ * doesn't need to be in stack's compartment, and stack can be null, a
+ * SavedFrame object, or a wrapper (CCW or Xray) around a SavedFrame object.
+ * SavedFrames not subsumed by |principals| are skipped.
+ *
+ * Optional indent parameter specifies the number of white spaces to indent
+ * each line.
+ */
+extern JS_PUBLIC_API bool BuildStackString(
+    JSContext* cx, JSPrincipals* principals, HandleObject stack,
+    MutableHandleString stringp, size_t indent = 0,
+    js::StackFormat stackFormat = js::StackFormat::Default);
+
+}  // namespace JS
+
+#endif  // js_Stack_h