diff options
Diffstat (limited to 'vendor/github.com/cilium/ebpf/internal/btf/strings.go')
-rw-r--r-- | vendor/github.com/cilium/ebpf/internal/btf/strings.go | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/vendor/github.com/cilium/ebpf/internal/btf/strings.go b/vendor/github.com/cilium/ebpf/internal/btf/strings.go new file mode 100644 index 000000000..8782643a0 --- /dev/null +++ b/vendor/github.com/cilium/ebpf/internal/btf/strings.go @@ -0,0 +1,60 @@ +package btf + +import ( + "bytes" + "errors" + "fmt" + "io" + "io/ioutil" +) + +type stringTable []byte + +func readStringTable(r io.Reader) (stringTable, error) { + contents, err := ioutil.ReadAll(r) + if err != nil { + return nil, fmt.Errorf("can't read string table: %v", err) + } + + if len(contents) < 1 { + return nil, errors.New("string table is empty") + } + + if contents[0] != '\x00' { + return nil, errors.New("first item in string table is non-empty") + } + + if contents[len(contents)-1] != '\x00' { + return nil, errors.New("string table isn't null terminated") + } + + return stringTable(contents), nil +} + +func (st stringTable) Lookup(offset uint32) (string, error) { + if int64(offset) > int64(^uint(0)>>1) { + return "", fmt.Errorf("offset %d overflows int", offset) + } + + pos := int(offset) + if pos >= len(st) { + return "", fmt.Errorf("offset %d is out of bounds", offset) + } + + if pos > 0 && st[pos-1] != '\x00' { + return "", fmt.Errorf("offset %d isn't start of a string", offset) + } + + str := st[pos:] + end := bytes.IndexByte(str, '\x00') + if end == -1 { + return "", fmt.Errorf("offset %d isn't null terminated", offset) + } + + return string(str[:end]), nil +} + +func (st stringTable) LookupName(offset uint32) (Name, error) { + str, err := st.Lookup(offset) + return Name(str), err +} |