Method loadProgramSections

elf_reader.go:370–434

loadProgramSections iterates ec's sections and emits a ProgramSpec for each function it finds. The resulting map is indexed by function name.

()

//
// The resulting map is indexed by function name.
func (ec *elfCode) loadProgramSections() (map[string]*ProgramSpec, error) {

	progs := make(map[string]*ProgramSpec)

	// Generate a ProgramSpec for each function found in each program section.
	var export []string
	for _, sec := range ec.sections {
		if sec.kind != programSection {
			continue
		}

		if len(sec.symbols) == 0 {
			return nil, fmt.Errorf("section %v: missing symbols", sec.Name)
		}

		if sec.ReaderAt == nil {
			return nil, fmt.Errorf("compressed program section is not supported")
		}

		funcs, err := ec.loadFunctions(sec)
		if err != nil {
			return nil, fmt.Errorf("section %v: %w", sec.Name, err)
		}

		progType, attachType, progFlags, attachTo := getProgType(sec.Name)

		for name, insns := range funcs {
			spec := &ProgramSpec{
				Name:          name,
				Type:          progType,
				Flags:         progFlags,
				AttachType:    attachType,
				AttachTo:      attachTo,
				SectionName:   sec.Name,
				License:       ec.license,
				KernelVersion: ec.version,
				Instructions:  insns,
				ByteOrder:     ec.ByteOrder,
			}

			// Function names must be unique within a single ELF blob.
			if progs[name] != nil {
				return nil, fmt.Errorf("duplicate program name %s", name)
			}
			progs[name] = spec

			if spec.SectionName != ".text" {
				export = append(export, name)
			}
		}
	}

	flattenPrograms(progs, export)

	// Hide programs (e.g. library functions) that were not explicitly emitted
	// to an ELF section. These could be exposed in a separate CollectionSpec
	// field later to allow them to be modified.
	for n, p := range progs {