/*
* Copyright (c) 2013 The Chromium Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef ERROR_HANDLING_ERROR_HANDLING_H_
#define ERROR_HANDLING_ERROR_HANDLING_H_
#include "error_handling/string_stream.h"
#include "sdk_util/macros.h"
EXTERN_C_BEGIN
struct NaClExceptionContext;
typedef void (*EHRawHandler)(struct NaClExceptionContext* context);
typedef void (*EHJsonHandler)(const char* str);
typedef struct {
uint32_t prog_ctr;
uint32_t frame_ptr;
uint32_t next_ptr;
} EHFrame;
/** Initialize error handling.
*
* Initializes the error handling to catch untrusted exceptions. The init
* functions will install an untrusted exception handler.
*
* The raw form will install the provided handler directly to the exception
* system.
*
* The json form will install a default handler which will walk the stack
* creating a valid JSON string which is passed to the provided handler.
*
* NOTE: Exception handling is enabled process wide.
* NOTE: Exception handling is not guaranteed to be available so it should
* not be considered an error if the request fails.
*/
void EHRequestExceptionsRaw(EHRawHandler callback);
void EHRequestExceptionsJson(EHJsonHandler callback);
/** Request an alternate signal handling stack for this thread.
*
* Specifies an alternate stack which will be used when this thread enters
* the exception handler. This is useful in cases when the threads original
* stack may have overflowed or may be too small to handler the exception.
*
* Returns the allocated stack or MAP_FAILED.
*
* NOTE: Unlike the handler, this is a per thread call.
* NOTE: If the allocation fails, the exception will still take place on the
* thread's original stack.
*/
void *EHRequestExceptionStackOnThread(size_t stack_size);
/** Determine if NaCl will forward exceptions.
*
* Returns non-zero if a hander has been installed and exceptions will
* be forwarded.
*
* NOTE: Exception handling is not guarenteed to be available so it should
* not be considered an error if the request fails.
*/
int EHHanderInstalled();
/** Fill an exception frame from an exception context. */
int EHGetTopFrame(sstream_t* ss, struct NaClExceptionContext* context,
EHFrame* frame);
/** Unwind the stack by one frame.
*
* Returns zero once it failes to unwind.
*/
int EHUnwindFrame(EHFrame* frame);
EXTERN_C_END
#endif // ERROR_HANDLING_ERROR_HANDLING_H_