crashpad/util/misc/capture_context.h
Justin Cohen 17a515d33d [ios] Bring up first draft Mach exception server.
Add Mach exception server and fill out exceptions snapshot.

Note that:
 - The 'capture' portion of this CL will be moved out of the snapshot
   interface and into a separate in-process dump to disk location.
 - All of the pointer dereferences need to be wrapped in vm_read.
 - The read-fast-and-dump logic in exception_snapshot will end up in a
   different file completely, but until we pick a
   serialization/deserialization method, keep it as-is.

Bug: crashpad:31
Change-Id: I44203aa44036a341d6b4517fde7ab0cb9d7e94d7
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/2160122
Commit-Queue: Justin Cohen <justincohen@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
2020-04-25 23:38:48 +00:00

87 lines
3.1 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

// Copyright 2014 The Crashpad Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef CRASHPAD_UTIL_MISC_CAPTURE_CONTEXT_H_
#define CRASHPAD_UTIL_MISC_CAPTURE_CONTEXT_H_
#include "build/build_config.h"
#if defined(OS_MACOSX)
#include <mach/mach.h>
#elif defined(OS_WIN)
#include <windows.h>
#elif defined(OS_LINUX) || defined(OS_ANDROID)
#include <ucontext.h>
#elif defined(OS_FUCHSIA)
#include <signal.h>
#endif // OS_MACOSX
namespace crashpad {
#if defined(OS_MACOSX)
#if defined(ARCH_CPU_X86_FAMILY)
using NativeCPUContext = x86_thread_state;
#elif defined(ARCH_CPU_ARM64)
using NativeCPUContext = arm_unified_thread_state;
#endif
#elif defined(OS_WIN)
using NativeCPUContext = CONTEXT;
#elif defined(OS_LINUX) || defined(OS_ANDROID) || defined(OS_FUCHSIA)
using NativeCPUContext = ucontext_t;
#endif // OS_MACOSX
//! \brief Saves the CPU context.
//!
//! The CPU context will be captured as accurately and completely as possible,
//! containing an atomic snapshot at the point of this functions return. This
//! function does not modify any registers.
//!
//! This function is a replacement for `RtlCaptureContext()` and `getcontext()`
//! which contain bugs and/or limitations.
//!
//! On 32-bit x86, `RtlCaptureContext()` requires that `ebp` be used as a frame
//! pointer, and returns `ebp`, `esp`, and `eip` out of sync with the other
//! registers. Both the 32-bit x86 and 64-bit x86_64 versions of
//! `RtlCaptureContext()` capture only the state of the integer registers,
//! ignoring floating-point and vector state.
//!
//! \param[out] cpu_context The structure to store the context in.
//!
//! \note The ABI may require that this function's argument is passed by
//! register, preventing this fuction from saving the original value of that
//! register. This occurs in the following circumstances:
//!
//! OS | Architecture | Register
//! --------------------|--------------|---------
//! Win | x86_64 | `%%rcx`
//! macOS/Linux/Fuchsia | x86_64 | `%%rdi`
//! Linux | ARM/ARM64 | `r0`/`x0`
//! Linux | MIPS/MIPS64 | `$a0`
//!
//! Additionally, the value `LR` on ARM/ARM64 will be the return address of
//! this function.
//!
//! If the value of these register prior to calling this function are needed
//! they must be obtained separately prior to calling this function. For
//! example:
//! \code
//! uint64_t rdi;
//! asm("movq %%rdi, %0" : "=m"(rdi));
//! \endcode
void CaptureContext(NativeCPUContext* cpu_context);
} // namespace crashpad
#endif // CRASHPAD_UTIL_MISC_CAPTURE_CONTEXT_H_