DLL_DECLARE void PgDtc_create_connect_string()

in connection.c [3592:3663]

• 42 lines of code
• 9 McCabe index (conditional complexity)

DLL_DECLARE void PgDtc_create_connect_string(void *self, char *connstr, int strsize)
{
	ConnectionClass	*conn = (ConnectionClass *) self;
	ConnInfo *ci = &(conn->connInfo);
	const char *drivername = ci->drivername;
	char	xaOptStr[32];

#if defined(_WIN32) && !defined(_WIN64)
	/*
	 * If this is an x86 driver running on an x64 host then the driver name
	 * passed to MSDTC must be the (x64) driver but the client app will be
	 * using the 32-bit driver name. So MSDTC.exe will fail to find the driver
	 * and we'll fail to recover XA transactions.
	 *
	 * IsWow64Process(...) would be the ideal function for this, but is only
	 * available on Windows 6+ (Vista/2k8). We'd use GetNativeSystemInfo, which
	 * is supported on XP and 2k3, instead, but that won't link with older
	 * SDKs.
	 *
	 * It's impler to just test the PROCESSOR_ARCHITEW6432 environment
	 * variable.
	 *
	 * See http://www.postgresql.org/message-id/53A45B59.70303@2ndquadrant.com
	 * for details on this issue.
	 */
	const char * const procenv = getenv("PROCESSOR_ARCHITEW6432");
	if (procenv != NULL && strcmp(procenv, "AMD64") == 0)
	{
		/*
		 * We're a 32-bit binary running under SysWow64 on a 64-bit host and need
		 * to pass a different driver name.
		 *
		 * To avoid playing memory management games, just return a different
		 * string constant depending on the unicode-ness of the driver.
		 *
		 * It probably doesn't matter whether we use the Unicode or ANSI driver
		 * for the XA transaction manager, but pick the same as the client driver
		 * to keep things as similar as possible.
		 */
		if (strcmp(drivername, DBMS_NAME) == 0)
#ifdef UNICODE_SUPPORT
		drivername = DBMS_NAME_UNICODE"(x64)";
#else
		drivername = DBMS_NAME_ANSI"(x64)";
#endif
	}
#endif // _WIN32 &&  !_WIN64

	if (0 >= ci->xa_opt)	return;
	switch (ci->xa_opt)
	{
		case DTC_CHECK_LINK_ONLY:
		case DTC_CHECK_BEFORE_LINK:
			SPRINTF_FIXED(xaOptStr, KEYWORD_DTC_CHECK "=0;");
			break;
		case DTC_CHECK_RM_CONNECTION:
			SPRINTF_FIXED(xaOptStr, KEYWORD_DTC_CHECK "=1;");
			break;
		default:
			*xaOptStr = '\0';
			break;
	}
	snprintf(connstr, strsize,
			 "DRIVER={%s};%s"
			 "SERVER=%s;PORT=%s;DATABASE=%s;"
			 "UID=%s;PWD=%s;" ABBR_SSLMODE "=%s",
			 drivername, xaOptStr,
			 ci->server, ci->port, ci->database, ci->username,
			 SAFE_NAME(ci->password), ci->sslmode
		);
	return;
}