breakpad/src/common/android/include/sys/ucontext.h
digit@chromium.org 7e3c538af1 Add custom getcontext() implementation for Android.
This adds a minimalistic implementation of getcontext()
for Android/ARM and Android/x86. The provided code is
in assembly and only implements the bare minimum required
by Breakpad to get the current processor state.

Note that:

- The FPU state is not saved to the ucontext_t on ARM.
  (that's actually the main difference with a normal
   getcontext() implementation).

  This is normal. On Linux/ARM, such state must be
  obtained with PTRACE_GETVFPREGS instead. This will
  be implemented in a future patch.

- On x86, only the 'regular' FPU state is saved, to
  mimic the GLibc/i386 implementation. The state of
  SSE/SSE2/etc registers is not part of the upstream
  getcontext() implementation.
Review URL: https://breakpad.appspot.com/444002

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1024 4c0a9323-5329-0410-9bdc-e9ce6186880e
2012-08-31 18:38:29 +00:00

176 lines
4.5 KiB
C

// Copyright (c) 2012, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef GOOGLE_BREAKPAD_COMMON_ANDROID_INCLUDE_SYS_UCONTEXT_H
#define GOOGLE_BREAKPAD_COMMON_ANDROID_INCLUDE_SYS_UCONTEXT_H
#include <sys/cdefs.h>
#include <signal.h>
#ifdef __cplusplus
extern "C" {
#endif // __cplusplus
#ifndef __BIONIC_HAVE_UCONTEXT_T
// Ensure that 'stack_t' is defined.
#include <asm/signal.h>
// This version of the Android C library headers do not provide ucontext_t.
// Provide custom definitions for Google Breakpad.
#if defined(__arm__)
// Ensure that 'struct sigcontext' is defined.
#include <asm/sigcontext.h>
typedef struct sigcontext mcontext_t;
// The ARM kernel uses a 64-bit signal mask.
typedef uint32_t kernel_sigmask_t[2];
typedef struct ucontext {
uint32_t uc_flags;
struct ucontext* uc_link;
stack_t uc_stack;
mcontext_t uc_mcontext;
kernel_sigmask_t uc_sigmask;
// Other fields are not used by Google Breakpad. Don't define them.
} ucontext_t;
#elif defined(__i386__)
/* 80-bit floating-point register */
struct _libc_fpreg {
unsigned short significand[4];
unsigned short exponent;
};
/* Simple floating-point state, see FNSTENV instruction */
struct _libc_fpstate {
unsigned long cw;
unsigned long sw;
unsigned long tag;
unsigned long ipoff;
unsigned long cssel;
unsigned long dataoff;
unsigned long datasel;
struct _libc_fpreg _st[8];
unsigned long status;
};
typedef uint32_t greg_t;
typedef struct {
uint32_t gregs[19];
struct _libc_fpstate* fpregs;
uint32_t oldmask;
uint32_t cr2;
} mcontext_t;
enum {
REG_GS = 0,
REG_FS,
REG_ES,
REG_DS,
REG_EDI,
REG_ESI,
REG_EBP,
REG_ESP,
REG_EBX,
REG_EDX,
REG_ECX,
REG_EAX,
REG_TRAPNO,
REG_ERR,
REG_EIP,
REG_CS,
REG_EFL,
REG_UESP,
REG_SS,
};
// The i386 kernel uses a 64-bit signal mask.
typedef uint32_t kernel_sigmask_t[2];
typedef struct ucontext {
uint32_t uc_flags;
struct ucontext* uc_link;
stack_t uc_stack;
mcontext_t uc_mcontext;
kernel_sigmask_t uc_sigmask;
struct _libc_fpstate __fpregs_mem;
} ucontext_t;
#elif defined(__mips__)
// Not supported by Google Breakpad at this point, but just in case.
typedef struct {
uint32_t regmask;
uint32_t status;
uint64_t pc;
uint64_t gregs[32];
uint64_t fpregs[32];
uint32_t acx;
uint32_t fpc_csr;
uint32_t fpc_eir;
uint32_t used_math;
uint32_t dsp;
uint64_t mdhi;
uint64_t mdlo;
uint32_t hi1;
uint32_t lo1;
uint32_t hi2;
uint32_t lo2;
uint32_t hi3;
uint32_t lo3;
} mcontext_t;
// The MIPS kernel uses a 128-bit signal mask.
typedef uint32_t kernel_sigmask_t[4];
typedef struct ucontext {
uint32_t uc_flags;
struct ucontext* uc_link;
stack_t uc_stack;
mcontext_t uc_mcontext;
kernel_sigmask_t uc_sigmask;
// Other fields are not used by Google Breakpad. Don't define them.
} ucontext_t;
#else
# error "Unsupported Android CPU ABI!"
#endif
#endif // __BIONIC_HAVE_UCONTEXT_T
#ifdef __cplusplus
} // extern "C"
#endif // __cplusplus
#endif // GOOGLE_BREAKPAD_COMMON_ANDROID_INCLUDE_SYS_UCONTEXT_H