firebird-mirror/src/common/fb_exception.cpp

#include "firebird.h"

//#include "fb_exception.h"

#include <string.h>
#include <errno.h>
#include <stdarg.h>
#include "gen/iberror.h"
#include "../common/classes/alloc.h"
#include "../common/classes/init.h"

namespace {

// This logic taken from JRD is bad, bad, bad!
// Replace it with attachment-level buffers whenever possible
const size_t ENGINE_FAILURE_SPACE = 4096;

typedef Firebird::CircularStringsBuffer<ENGINE_FAILURE_SPACE> CircularBuffer;

class InterlockedStringsBuffer : public CircularBuffer
{
public:
	explicit InterlockedStringsBuffer(Firebird::MemoryPool&)
		: CircularBuffer()
	{ }
	virtual const char* alloc(const char* string, size_t& length)
	{
		Firebird::MutexLockGuard guard(buffer_lock);
		return CircularBuffer::alloc(string, length);
	}
private:
	Firebird::Mutex buffer_lock;
};

char* dupStringTemp2(const char* s)
{
	const size_t len = strlen(s);
	char *string = FB_NEW(*getDefaultMemoryPool()) char[len + 1];
	memcpy(string, s, len + 1);
	return string;
}

ISC_STATUS dupStringTemp(const char* s)
{
	return (ISC_STATUS)(IPTR) dupStringTemp2(s);
}

void fill_status(ISC_STATUS* ptr, const ISC_STATUS* orig_status)
{
	// Move in status and clone transient strings
	while (true)
	{
		const ISC_STATUS type = *ptr++ = *orig_status++;

		switch (type)
		{
		case isc_arg_end:
			return;
		case isc_arg_cstring:
			{
				const size_t len = *ptr++ = *orig_status++;
				char *string = FB_NEW(*getDefaultMemoryPool()) char[len];
				const char *temp = reinterpret_cast<char*>(*orig_status++);
				memcpy(string, temp, len);
				*ptr++ = (ISC_STATUS)(IPTR)(string);
				break;
			}
		case isc_arg_string:
		case isc_arg_interpreted:
		case isc_arg_sql_state:
			*ptr++ = dupStringTemp(reinterpret_cast<char*>(*orig_status++));
			break;
		default:
			*ptr++ = *orig_status++;
			break;
		}
	}
}

Firebird::GlobalPtr<InterlockedStringsBuffer> engine_failures;

} // namespace

namespace Firebird {

/********************************* StringsBuffer *******************************/

void StringsBuffer::makePermanentVector(ISC_STATUS* perm, const ISC_STATUS* trans)
{
	while (true)
	{
		const ISC_STATUS type = *perm++ = *trans++;

		switch (type)
		{
		case isc_arg_end:
			return;
		case isc_arg_cstring:
			{
				size_t len = *perm++ = *trans++;
				const char* temp = reinterpret_cast<char*>(*trans++);
				*perm++ = (ISC_STATUS)(IPTR) (alloc(temp, len));
				perm[-2] = len;
			}
			break;
		case isc_arg_string:
		case isc_arg_interpreted:
		case isc_arg_sql_state:
			{
				const char* temp = reinterpret_cast<char*>(*trans++);
				size_t len = strlen(temp);
				*perm++ = (ISC_STATUS)(IPTR) (alloc(temp, len));
			}
			break;
		default:
			*perm++ = *trans++;
			break;
		}
	}
}

void StringsBuffer::makeEnginePermanentVector(ISC_STATUS* v)
{
	engine_failures->makePermanentVector(v, v);
}

/********************************* status_exception *******************************/

status_exception::status_exception() throw() :
	m_strings_permanent(true)
{
	memset(m_status_vector, 0, sizeof(m_status_vector));
}

status_exception::status_exception(const ISC_STATUS *status_vector, bool permanent) throw() :
	m_strings_permanent(true)
{
	m_status_vector[0] = isc_arg_end;

	if (status_vector)
	{
		set_status(status_vector, permanent);
	}
}

void status_exception::set_status(const ISC_STATUS *new_vector, bool permanent) throw()
{
	fb_assert(new_vector != 0);

	release_vector();

	m_strings_permanent = permanent;

	ISC_STATUS *ptr = m_status_vector;
	while (true)
	{
		const ISC_STATUS type = *ptr++ = *new_vector++;
		if (type == isc_arg_end)
			break;
		if (type == isc_arg_cstring)
			*ptr++ = *new_vector++;
		*ptr++ = *new_vector++;
	}
}

void status_exception::release_vector() throw()
{
	if (m_strings_permanent)
		return;

	// Free owned strings
	ISC_STATUS *ptr = m_status_vector;
	while (true)
	{
		const ISC_STATUS type = *ptr++;

		switch (type)
		{
		case isc_arg_end:
			return;
		case isc_arg_cstring:
			ptr++;
			delete[] reinterpret_cast<char*>(*ptr++);
			break;
		case isc_arg_string:
		case isc_arg_interpreted:
		case isc_arg_sql_state:
			delete[] reinterpret_cast<char*>(*ptr++);
			break;
		default:
			ptr++;
			break;
		}
	}
}

status_exception::~status_exception() throw()
{
	release_vector();
}

/********************************* fatal_exception *******************************/

void fatal_exception::raiseFmt(const char* format, ...)
{
	va_list args;
	va_start(args, format);
	char buffer[1024];
	VSNPRINTF(buffer, sizeof(buffer), format, args);
	buffer[sizeof(buffer) - 1] = 0;
	va_end(args);
	throw fatal_exception(buffer);
}

void status_exception::raise(const ISC_STATUS *status_vector)
{
	throw status_exception(status_vector, true);
}

void status_exception::raise(const Arg::StatusVector& statusVector)
{
	ISC_STATUS_ARRAY temp;
	fill_status(temp, statusVector.value());
	throw status_exception(temp, false);
}

ISC_STATUS status_exception::stuff_exception(ISC_STATUS* const status_vector, StringsBuffer* sb) const throw()
{
	const ISC_STATUS *ptr = value();
	ISC_STATUS *sv = status_vector;
	if (!sb)
	{
		sb = &engine_failures;
	}

	if (strings_permanent())
	{
		// Copy status vector
		while (true)
		{
			const ISC_STATUS type = *sv++ = *ptr++;
			if (type == isc_arg_end)
				break;
			if (type == isc_arg_cstring)
				*sv++ = *ptr++;
			*sv++ = *ptr++;
		}
	}
	else {
		// Move in status and clone transient strings
		sb->makePermanentVector(sv, ptr);
	}

	return status_vector[1];
}

/********************************* BadAlloc ****************************/

void BadAlloc::raise()
{
	throw BadAlloc();
}

ISC_STATUS BadAlloc::stuff_exception(ISC_STATUS* const status_vector, StringsBuffer* sb) const throw()
{
	ISC_STATUS *sv = status_vector;

	*sv++ = isc_arg_gds;
	*sv++ = isc_virmemexh;
	*sv++ = isc_arg_end;

	return status_vector[1];
}

/********************************* LongJump ****************************/

void LongJump::raise()
{
	throw LongJump();
}

ISC_STATUS LongJump::stuff_exception(ISC_STATUS* const status_vector, StringsBuffer* sb) const throw()
{
   /*
	* Do nothing for a while - not all utilities are ready,
	* status_vector is passed in them by other means.
	* Ideally status_exception should be always used for it,
	* and we should activate the following code:

	ISC_STATUS *sv = status_vector;
	if (!sb)
	{
		sb = &engine_failures;
	}

	const char *temp = "Unexpected Firebird::LongJump";

	*sv++ = isc_arg_gds;
	*sv++ = isc_random;
	*sv++ = isc_arg_string;
	*sv++ = (ISC_STATUS)(IPTR) (sb->alloc(temp, strlen(temp)));
	*sv++ = isc_arg_end;
	*/

	return status_vector[1];
}


/********************************* system_error ****************************/

system_error::system_error(const char* syscall, int error_code) :
	status_exception(0, false), errorCode(error_code)
{
	Arg::Gds temp(isc_sys_request);
	temp << Arg::Str(dupStringTemp2(syscall));
	temp << SYS_ERR(errorCode);
	set_status(temp.value(), false);
}

void system_error::raise(const char* syscall, int error_code)
{
	throw system_error(syscall, error_code);
}

void system_error::raise(const char* syscall)
{
	throw system_error(syscall, getSystemError());
}

int system_error::getSystemError()
{
#ifdef WIN_NT
	return GetLastError();
#else
	return errno;
#endif
}

/********************************* system_call_failed ****************************/

system_call_failed::system_call_failed(const char* syscall, int error_code) :
	system_error(syscall, error_code)
{
#ifdef DEV_BUILD
	// raised failed system call exception in DEV_BUILD in 99.99% means
	// problems with the code - let's create memory dump now
	abort();
#endif
}

void system_call_failed::raise(const char* syscall, int error_code)
{
	throw system_call_failed(syscall, error_code);
}

void system_call_failed::raise(const char* syscall)
{
	throw system_call_failed(syscall, getSystemError());
}

/********************************* fatal_exception ********************************/

fatal_exception::fatal_exception(const char* message) :
	status_exception(0, false)
{
	const ISC_STATUS temp[] =
	{
		isc_arg_gds,
		isc_random,
		isc_arg_string, dupStringTemp(message),
		isc_arg_end
	};
	set_status(temp, false);
}

// Moved to the header due to gpre. Gpre non-static can't receive it, but we
// want to avoid problems with picky compilers that can't find what().
// We can't link this file into normal gpre.
// Keep in sync with the constructor above, please; "message" becomes 4th element
// after initialization of status vector.
//const char* fatal_exception::what() const throw()
//{
//	return reinterpret_cast<const char*>(value()[3]);
//}

void fatal_exception::raise(const char* message)
{
	throw fatal_exception(message);
}

/************************** exception handling routines ***************************/

// Serialize exception into status_vector, put transient strings from exception into given StringsBuffer
ISC_STATUS stuff_exception(ISC_STATUS *status_vector, const Firebird::Exception& ex, StringsBuffer* sb) throw()
{
	return ex.stuff_exception(status_vector, sb);
}

}	// namespace Firebird