// The contents of this file are subject to the BOINC Public License
// Version 1.0 (the "License"); you may not use this file except in
// compliance with the License. You may obtain a copy of the License at
// http://boinc.berkeley.edu/license_1.0.txt
//
// Software distributed under the License is distributed on an "AS IS"
// basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
// License for the specific language governing rights and limitations
// under the License.
//
// The Original Code is the Berkeley Open Infrastructure for Network Computing.
//
// The Initial Developer of the Original Code is the SETI@home project.
// Portions created by the SETI@home project are Copyright (C) 2002
// University of California at Berkeley. All Rights Reserved.
//
// Contributor(s):
//

#ifdef _WIN32
#include <windows.h>
#include "win/Stackwalker.h"
#else
#include "config.h"
#endif

#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#ifdef HAVE_SIGNAL_H
#include <signal.h>
#endif

#include "boinc_diagnostics.h"
#include "app_ipc.h"
#include "util.h"


// ****************************************************************************
// ****************************************************************************
//
// Externally defined functions used by the diagnostics library
//
// ****************************************************************************
// ****************************************************************************

extern bool boinc_is_standalone();
extern bool boinc_is_verbose();


// ****************************************************************************
// ****************************************************************************
//
// Diagnostics Support for Windows 95/98/ME/2000/XP/2003
//
// ****************************************************************************
// ****************************************************************************

#ifdef _WIN32

// Forward declare implementation specific functions - Windows Platform Only.
LONG CALLBACK boinc_catch_signal(EXCEPTION_POINTERS *ExceptionInfo);
int __cdecl boinc_message_reporting( int reportType, char *szMsg, int *retVal );


//
// Function: boinc_init_diag
//
// Purpose:  Used to initialize the diagnostics environment.
//
// Date:     02/05/04
//
int boinc_init_diag() {

	LPVOID lpErrorTrap = NULL;

	lpErrorTrap = (LPVOID) freopen(STDERR_FILE, "a", stderr);
	if ( NULL == lpErrorTrap )
		throw boinc_file_operation_exception(__FILE__, __LINE__, "Failed to reopen stderr for diagnostics redirection");

#ifdef _DEBUG
	_CrtSetReportHook( boinc_message_reporting );
#endif

	return BOINC_SUCCESS;
}


//
// Function: boinc_finish_diag
//
// Purpose:  Used to cleanup the diagnostics environment.
//
// Date:     02/05/04
//
int boinc_finish_diag() {
	return BOINC_SUCCESS;
}


//
// Function: boinc_install_signal_handlers
//
// Purpose:  Used to setup an unhandled exception filter on Windows
//
// Date:     02/05/04
//
int boinc_install_signal_handlers() {

	SetUnhandledExceptionFilter( boinc_catch_signal );

	return BOINC_SUCCESS;
}

//
// Function: boinc_catch_signal
//
// Purpose:  Used to unwind the stack and spew the callstack to stderr. Terminate the
//               process afterwards and return the exception code as the exit code.
//
// Date:     02/05/04
//
LONG CALLBACK boinc_catch_signal(EXCEPTION_POINTERS *pExPtrs) {

	// Snagged from the latest stackwalker code base.  This allows us to grab
	//   callstacks even in a stack overflow scenario
	if ( pExPtrs->ExceptionRecord->ExceptionCode == EXCEPTION_STACK_OVERFLOW )
	{
		static char MyStack[1024*128];  // be sure that we have enought space...
		// it assumes that DS and SS are the same!!! (this is the case for Win32)
		// change the stack only if the selectors are the same (this is the case for Win32)
		//__asm push offset MyStack[1024*128];
		//__asm pop esp;
		__asm mov eax,offset MyStack[1024*128];
		__asm mov esp,eax;
	}

	PVOID exceptionAddr = pExPtrs->ExceptionRecord->ExceptionAddress;
    DWORD exceptionCode = pExPtrs->ExceptionRecord->ExceptionCode;

	LONG  lReturnValue = NULL;
	char  status[256];
	char  substatus[256];
    
	static long   lDetectNestedException = 0;

    // If we've been in this procedure before, something went wrong so we immediately exit
	if ( InterlockedIncrement(&lDetectNestedException) > 1 ) {
		TerminateProcess( GetCurrentProcess(), BOINC_NESTED_UNHANDLED_EXCEPTION_DETECTED );
	}

    switch ( exceptionCode ) {
        case EXCEPTION_ACCESS_VIOLATION:
			safe_strncpy( status, "Access Violation", sizeof(status) );
			if ( pExPtrs->ExceptionRecord->NumberParameters == 2 ) {
				switch( pExPtrs->ExceptionRecord->ExceptionInformation[0] ) {
				case 0: // read attempt
					sprintf( substatus, "read attempt to address 0x%8.8X", pExPtrs->ExceptionRecord->ExceptionInformation[1] );
					break;
				case 1: // write attempt
					sprintf( substatus, "write attempt to address 0x%8.8X", pExPtrs->ExceptionRecord->ExceptionInformation[1] );
					break;
				}
			}
			break;
        case EXCEPTION_DATATYPE_MISALIGNMENT: 
			safe_strncpy( status, "Data Type Misalignment", sizeof(status) );
			break;
        case EXCEPTION_BREAKPOINT: 
			safe_strncpy( status, "Breakpoint Encountered", sizeof(status) );
			break;
        case EXCEPTION_SINGLE_STEP: 
			safe_strncpy( status, "Single Instruction Executed", sizeof(status) );
			break;
        case EXCEPTION_ARRAY_BOUNDS_EXCEEDED: 
			safe_strncpy( status, "Array Bounds Exceeded", sizeof(status) );
			break;
        case EXCEPTION_FLT_DENORMAL_OPERAND: 
			safe_strncpy( status, "Float Denormal Operand", sizeof(status) );
			break;
        case EXCEPTION_FLT_DIVIDE_BY_ZERO: 
			safe_strncpy( status, "Divide by Zero", sizeof(status) ); 
			break;
        case EXCEPTION_FLT_INEXACT_RESULT: 
			safe_strncpy( status, "Float Inexact Result", sizeof(status) ); 
			break;
        case EXCEPTION_FLT_INVALID_OPERATION: 
			safe_strncpy( status, "Float Invalid Operation", sizeof(status) );
			break;
        case EXCEPTION_FLT_OVERFLOW: 
			safe_strncpy( status, "Float Overflow", sizeof(status) );
			break;
        case EXCEPTION_FLT_STACK_CHECK: 
			safe_strncpy( status, "Float Stack Check", sizeof(status) );
			break;
        case EXCEPTION_FLT_UNDERFLOW: 
			safe_strncpy( status, "Float Underflow", sizeof(status) );
			break;
        case EXCEPTION_INT_DIVIDE_BY_ZERO: 
			safe_strncpy( status, "Integer Divide by Zero", sizeof(status) );
			break;
        case EXCEPTION_INT_OVERFLOW: 
			safe_strncpy( status, "Integer Overflow", sizeof(status) );
			break;
        case EXCEPTION_PRIV_INSTRUCTION: 
			safe_strncpy( status, "Privileged Instruction", sizeof(status) );
			break;
        case EXCEPTION_IN_PAGE_ERROR: 
			safe_strncpy( status, "In Page Error", sizeof(status) );
			break;
        case EXCEPTION_ILLEGAL_INSTRUCTION: 
			safe_strncpy( status, "Illegal Instruction", sizeof(status) );
			break;
        case EXCEPTION_NONCONTINUABLE_EXCEPTION: 
			safe_strncpy( status, "Noncontinuable Exception", sizeof(status) );
			break;
        case EXCEPTION_STACK_OVERFLOW: 
			safe_strncpy( status, "Stack Overflow", sizeof(status) );
			break;
        case EXCEPTION_INVALID_DISPOSITION: 
			safe_strncpy( status, "Invalid Disposition", sizeof(status) );
			break;
        case EXCEPTION_GUARD_PAGE: 
			safe_strncpy( status, "Guard Page Violation", sizeof(status) );
			break;
        case EXCEPTION_INVALID_HANDLE: 
			safe_strncpy( status, "Invalid Handle", sizeof(status) );
			break;
        case CONTROL_C_EXIT: 
			safe_strncpy( status, "Ctrl+C Exit", sizeof(status) );
			break;
        default: 
			safe_strncpy( status, "Unknown exception", sizeof(status) );
			break;
    }

	fprintf( stderr, "\n***UNHANDLED EXCEPTION****\n" );
	if ( EXCEPTION_ACCESS_VIOLATION == exceptionCode ) {
		fprintf( stderr, "Reason: %s (0x%x) at address 0x%p %s\n\n", status, exceptionCode, exceptionAddr, substatus );
	} else {
		fprintf( stderr, "Reason: %s (0x%x) at address 0x%p\n\n", status, exceptionCode, exceptionAddr );
	}
    fflush( stderr );

	// Unwind the stack and spew it to stderr
	StackwalkFilter( pExPtrs, EXCEPTION_EXECUTE_HANDLER, NULL );

	fprintf( stderr, "Exiting...\n" );
    fflush( stderr );

	// Force terminate the app letting BOINC know an unknown exception has occurred.
	TerminateProcess( GetCurrentProcess(), pExPtrs->ExceptionRecord->ExceptionCode );

	// We won't make it to this point, but make the compiler happy anyway.
	return 1;
}


#ifdef _DEBUG

//
// Function: boinc_message_reporting
//
// Purpose:  Trap ASSERTs and TRACEs from the CRT and spew them to stderr.
//
// Date:     02/05/04
//
int __cdecl boinc_message_reporting( int reportType, char *szMsg, int *retVal ){ 
	(*retVal) = 0; 

	switch(reportType){

		case _CRT_WARN:
		case _CRT_ERROR:
			OutputDebugString(szMsg);			// Reports string to the debugger output window
			fprintf( stderr, "%s", szMsg );
			fflush( stderr );
			break;
		case _CRT_ASSERT:
			fprintf( stderr, "ASSERT: %s\n", szMsg );
			fflush( stderr );
			(*retVal) = 1;
			break;

	}

	return(TRUE);
} 


//
// Function: boinc_trace
//
// Purpose:  Converts the BOINCTRACE macro into a single string and report it
//             to the CRT so it can be reported via the normal means.
//
// Date:     02/05/04
//
void boinc_trace(const char *pszFormat, ...)
{
	static char szBuffer[1024];

	// Trace messages should only be reported if running as a standalone 
	//   application or told too.
	if ( boinc_is_standalone() || boinc_is_verbose() ) {

		memset(szBuffer, 0, sizeof(szBuffer));

		va_list ptr;
		va_start(ptr, pszFormat);

		BOINCASSERT( -1 != _vsnprintf(szBuffer, sizeof(szBuffer), pszFormat, ptr) );

		va_end(ptr);

		_CrtDbgReport(_CRT_WARN, NULL, NULL, NULL, "TRACE: %s", szBuffer);
	}
}


//
// Function: boinc_info_debug
//
// Purpose:  Converts the BOINCINFO macro into a single string and report it
//             to stderr so it can be reported via the normal means.
//
// Date:     02/05/04
//
void boinc_info_debug(const char *pszFormat, ...)
{
	static char szBuffer[1024];

	memset(szBuffer, 0, sizeof(szBuffer));

	va_list ptr;
	va_start(ptr, pszFormat);

	BOINCASSERT( -1 != _vsnprintf(szBuffer, sizeof(szBuffer), pszFormat, ptr) );

	va_end(ptr);

	_CrtDbgReport(_CRT_WARN, NULL, NULL, NULL, "%s", szBuffer);
}


#else // _DEBUG

//
// Function: boinc_info_release
//
// Purpose:  Converts the BOINCINFO macro into a single string and report it
//             to stderr so it can be reported via the normal means.
//
// Date:     02/05/04
//
void boinc_info_release(const char *pszFormat, ...)
{
	static char szBuffer[1024];

	memset(szBuffer, 0, sizeof(szBuffer));

	va_list ptr;
	va_start(ptr, pszFormat);

	_vsnprintf(szBuffer, sizeof(szBuffer), pszFormat, ptr);

	va_end(ptr);

	fprintf( stderr, "%s", szBuffer );
	fflush( stderr );
}

#endif // _DEBUG

#endif // _WIN32


// ****************************************************************************
// ****************************************************************************
//
// Diagnostics for POSIX Compatible systems.
//
// ****************************************************************************
// ****************************************************************************

#ifdef HAVE_SIGNAL_H

// Forward declare implementation functions - POSIX Platform Only.
extern void boinc_catch_signal(int signal);
extern void boinc_quit(int sig);

// Set a signal handler but only if it is not currently ignored
void boinc_set_signal_handler(int sig)
{
#ifdef HAVE_SIGACTION
    struct sigaction temp;
    sigaction(sig, NULL, &temp);
    if (temp.sa_handler != SIG_IGN) {
	 temp.sa_handler = boinc_catch_signal;
	 sigemptyset(&temp.sa_mask);
	 sigaction(sig, &temp, NULL);
    }
#else
    void (*temp)(int);
    temp = signal(sig, boinc_catch_signal);
    if (temp == SIG_IGN) {
	signal(sig, SIG_IGN);
    }
#endif
}

int boinc_install_signal_handlers() {
    boinc_set_signal_handler(SIGHUP);
    boinc_set_signal_handler(SIGINT);
    boinc_set_signal_handler(SIGQUIT);
    boinc_set_signal_handler(SIGILL);
    boinc_set_signal_handler(SIGABRT);
    boinc_set_signal_handler(SIGBUS);
    boinc_set_signal_handler(SIGSEGV);
    boinc_set_signal_handler(SIGSYS);
    boinc_set_signal_handler(SIGPIPE);
    return 0;
}

void boinc_catch_signal(int signal) {
    switch(signal) {
        case SIGHUP: fprintf(stderr, "SIGHUP: terminal line hangup"); break;
        case SIGINT: fprintf(stderr, "SIGINT: interrupt program"); break;
        case SIGILL: fprintf(stderr, "SIGILL: illegal instruction"); break;
        case SIGABRT: fprintf(stderr, "SIGABRT: abort called"); break;
        case SIGBUS: fprintf(stderr, "SIGBUS: bus error"); break;
        case SIGSEGV: fprintf(stderr, "SIGSEGV: segmentation violation"); break;
        case SIGSYS: fprintf(stderr, "SIGSYS: system call given invalid argument"); break;
        case SIGPIPE: fprintf(stderr, "SIGPIPE: write on a pipe with no reader"); break;
        default: fprintf(stderr, "unknown signal %d", signal); break;
    }
    fprintf(stderr, "\nExiting...\n");
    exit(ERR_SIGNAL_CATCH);
}

void boinc_quit(int sig) {
    signal(SIGQUIT, boinc_quit);    // reset signal
    time_to_quit = true;
}

#endif