| // 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_APPLE) |
| #include <mach/mach.h> |
| #elif defined(OS_WIN) |
| #include <windows.h> |
| #elif defined(OS_LINUX) || defined(OS_CHROMEOS) || defined(OS_ANDROID) |
| #include <ucontext.h> |
| #elif defined(OS_FUCHSIA) |
| #include <signal.h> |
| #endif // OS_APPLE |
| |
| namespace crashpad { |
| |
| #if defined(OS_APPLE) |
| #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_CHROMEOS) || defined(OS_ANDROID) || \ |
| defined(OS_FUCHSIA) |
| using NativeCPUContext = ucontext_t; |
| #endif // OS_APPLE |
| |
| //! \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 function’s 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_ |