func()

in pkg/mgmapi/config_reader.go [199:275]

• 30 lines of code
• 7 McCabe index (conditional complexity)

func (cr *configReader) readConfig(sectionTypeFilter cfgSectionType, fromNodeId, configKey uint32) configValue {

	// Start reading the header.
	//
	// Magic Word (2 words) - ignored
	// Header section (7 words) :
	// 1. Total length in words of configuration binary
	// 2. Configuration binary version (this is version 2)
	// 3. Number of default sections in configuration binary
	//    - Data node defaults
	//    - API node defaults
	//    - MGM server node defaults
	//    - TCP communication defaults
	//    - SHM communication defaults
	//    So, the value is always 5 in this version
	// 4. Number of data nodes
	// 5. Number of API nodes
	// 6. Number of MGM server nodes
	// 7. Number of communication sections

	// read the header - starts after the magic word
	cr.offset = 8
	defer func() {
		// reset offset after reading
		cr.offset = 0
	}()

	cr.totalLengthInWords = cr.readUint32()
	cr.version = cr.readUint32()
	// configReader can handle only version 2
	if cr.version != 2 {
		debug.Panic("unexpected version in get config reply")
		return nil
	}

	cr.numOfDefaultSections = cr.readUint32()
	for i := 0; i < 3; i++ {
		cr.numOfNodes += cr.readUint32()
	}
	cr.numOfCommSections = cr.readUint32()

	// Start reading the sections
	//
	// 1. The default sections
	//    - Data node defaults
	//    - API node defaults
	//    - MGM server node defaults
	//    - TCP communication defaults
	//    - SHM communication defaults
	// 2. System section
	// 3. Node sections
	//    (Ordered based on node ids of nodes of all types)
	// 4. Communication sections - ignored

	// start reading the sections
	// default sections
	for ds := 0; ds < int(cr.numOfDefaultSections); ds++ {
		// no need to handle the return value as the reading has to continue anyways
		cr.readEntryFromSection(false, sectionTypeFilter, 0, configKey)
	}

	// system section
	if cr.readEntryFromSection(false, sectionTypeFilter, 0, configKey) {
		return cr.value
	}

	// node sections
	for n := 0; n < int(cr.numOfNodes); n++ {
		if cr.readEntryFromSection(true, sectionTypeFilter, fromNodeId, configKey) {
			return cr.value
		}
	}

	// control should never reach here if the method is used right
	debug.Panic("failed to find the desired config key")
	return nil
}