Light initialization logic refactor + remove multiple returns

[thnkslprpt]

Checklist

• I reviewed the Contributing Guide.
• I performed a cursory search to see if the bug report is relevant, not redundant, nor in conflict with other tickets.

Describe the bug
TO_LAB_init contains 5 exit points - where possible this should be reduced to 1 (or maximum 2 if needed, for early exit after input-validation failure).

to_lab/fsw/src/to_lab_app.c

Lines 117 to 155 in ec09026

	status = CFE_EVS_Register(NULL, 0, CFE_EVS_EventFilter_BINARY);
	if (status != CFE_SUCCESS)
	{
	CFE_ES_WriteToSysLog("TO_LAB: Error registering for Event Services, RC = 0x%08X\n", (unsigned int)status);
	return status;
	}
	/*
	** Initialize housekeeping packet (clear user data area)...
	*/
	CFE_MSG_Init(CFE_MSG_PTR(TO_LAB_Global.HkTlm.TelemetryHeader), CFE_SB_ValueToMsgId(TO_LAB_HK_TLM_MID),
	sizeof(TO_LAB_Global.HkTlm));
	status =
	CFE_TBL_Register(&TO_LAB_Global.SubsTblHandle, "TO_LAB_Subs", sizeof(TO_LAB_Subs_t), CFE_TBL_OPT_DEFAULT, NULL);
	if (status != CFE_SUCCESS)
	{
	CFE_EVS_SendEvent(TO_LAB_TBL_ERR_EID, CFE_EVS_EventType_ERROR, "L%d TO Can't register table status %i",
	__LINE__, (int)status);
	return status;
	}
	status = CFE_TBL_Load(TO_LAB_Global.SubsTblHandle, CFE_TBL_SRC_FILE, "/cf/to_lab_sub.tbl");
	if (status != CFE_SUCCESS)
	{
	CFE_EVS_SendEvent(TO_LAB_TBL_ERR_EID, CFE_EVS_EventType_ERROR, "L%d TO Can't load table status %i", __LINE__,
	(int)status);
	return status;
	}
	status = CFE_TBL_GetAddress((void **)&TblPtr, TO_LAB_Global.SubsTblHandle);
	if (status != CFE_SUCCESS && status != CFE_TBL_INFO_UPDATED)
	{
	CFE_EVS_SendEvent(TO_LAB_TBL_ERR_EID, CFE_EVS_EventType_ERROR, "L%d TO Can't get table addr status %i",
	__LINE__, (int)status);
	return status;

Also, the current logic doesn't contain early returns or status-guards after the first call to CFE_SB_CreatePipe, so subsequent initialization steps are attempted even if previous steps failed, and successful initialization is reported even if no pipes were created:

to_lab/fsw/src/to_lab_app.c

Lines 161 to 206 in ec09026

	status = CFE_SB_CreatePipe(&TO_LAB_Global.Cmd_pipe, PipeDepth, PipeName);
	if (status == CFE_SUCCESS)
	{
	CFE_SB_Subscribe(CFE_SB_ValueToMsgId(TO_LAB_CMD_MID), TO_LAB_Global.Cmd_pipe);
	CFE_SB_Subscribe(CFE_SB_ValueToMsgId(TO_LAB_SEND_HK_MID), TO_LAB_Global.Cmd_pipe);
	}
	else
	CFE_EVS_SendEvent(TO_LAB_CR_PIPE_ERR_EID, CFE_EVS_EventType_ERROR, "L%d TO Can't create cmd pipe status %i",
	__LINE__, (int)status);
	/* Create TO TLM pipe */
	status = CFE_SB_CreatePipe(&TO_LAB_Global.Tlm_pipe, ToTlmPipeDepth, ToTlmPipeName);
	if (status != CFE_SUCCESS)
	{
	CFE_EVS_SendEvent(TO_LAB_TLMPIPE_ERR_EID, CFE_EVS_EventType_ERROR, "L%d TO Can't create Tlm pipe status %i",
	__LINE__, (int)status);
	}
	/* Subscriptions for TLM pipe*/
	SubEntry = TO_LAB_Global.SubsTblPtr->Subs;
	for (i = 0; i < TO_LAB_MAX_SUBSCRIPTIONS; i++)
	{
	if (!CFE_SB_IsValidMsgId(SubEntry->Stream))
	{
	/* Only process until invalid MsgId is found*/
	break;
	}
	status = CFE_SB_SubscribeEx(SubEntry->Stream, TO_LAB_Global.Tlm_pipe, SubEntry->Flags, SubEntry->BufLimit);
	if (status != CFE_SUCCESS)
	{
	CFE_EVS_SendEvent(TO_LAB_SUBSCRIBE_ERR_EID, CFE_EVS_EventType_ERROR,
	"L%d TO Can't subscribe to stream 0x%x status %i", __LINE__,
	(unsigned int)CFE_SB_MsgIdToValue(SubEntry->Stream), (int)status);
	}
	++SubEntry;
	}
	/*
	** Install the delete handler
	*/
	OS_TaskInstallDeleteHandler(&TO_LAB_delete_callback);
	CFE_EVS_SendEvent(TO_LAB_INIT_INF_EID, CFE_EVS_EventType_INFORMATION,
	"TO Lab Initialized.%s, Awaiting enable command.", TO_LAB_VERSION_STRING);

Expected behavior
Single exit point.

Reporter Info
Avi Weiss   @thnkslprpt