diff options
Diffstat (limited to 'vendor/github.com/opencontainers/runc/libcontainer/cgroups/fscommon/utils.go')
-rw-r--r-- | vendor/github.com/opencontainers/runc/libcontainer/cgroups/fscommon/utils.go | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/vendor/github.com/opencontainers/runc/libcontainer/cgroups/fscommon/utils.go b/vendor/github.com/opencontainers/runc/libcontainer/cgroups/fscommon/utils.go new file mode 100644 index 000000000..f4a51c9e5 --- /dev/null +++ b/vendor/github.com/opencontainers/runc/libcontainer/cgroups/fscommon/utils.go @@ -0,0 +1,145 @@ +package fscommon + +import ( + "errors" + "fmt" + "math" + "path" + "strconv" + "strings" + + "github.com/opencontainers/runc/libcontainer/cgroups" +) + +var ( + // Deprecated: use cgroups.OpenFile instead. + OpenFile = cgroups.OpenFile + // Deprecated: use cgroups.ReadFile instead. + ReadFile = cgroups.ReadFile + // Deprecated: use cgroups.WriteFile instead. + WriteFile = cgroups.WriteFile +) + +// ParseError records a parse error details, including the file path. +type ParseError struct { + Path string + File string + Err error +} + +func (e *ParseError) Error() string { + return "unable to parse " + path.Join(e.Path, e.File) + ": " + e.Err.Error() +} + +func (e *ParseError) Unwrap() error { return e.Err } + +// ParseUint converts a string to an uint64 integer. +// Negative values are returned at zero as, due to kernel bugs, +// some of the memory cgroup stats can be negative. +func ParseUint(s string, base, bitSize int) (uint64, error) { + value, err := strconv.ParseUint(s, base, bitSize) + if err != nil { + intValue, intErr := strconv.ParseInt(s, base, bitSize) + // 1. Handle negative values greater than MinInt64 (and) + // 2. Handle negative values lesser than MinInt64 + if intErr == nil && intValue < 0 { + return 0, nil + } else if errors.Is(intErr, strconv.ErrRange) && intValue < 0 { + return 0, nil + } + + return value, err + } + + return value, nil +} + +// ParseKeyValue parses a space-separated "name value" kind of cgroup +// parameter and returns its key as a string, and its value as uint64 +// (ParseUint is used to convert the value). For example, +// "io_service_bytes 1234" will be returned as "io_service_bytes", 1234. +func ParseKeyValue(t string) (string, uint64, error) { + parts := strings.SplitN(t, " ", 3) + if len(parts) != 2 { + return "", 0, fmt.Errorf("line %q is not in key value format", t) + } + + value, err := ParseUint(parts[1], 10, 64) + if err != nil { + return "", 0, err + } + + return parts[0], value, nil +} + +// GetValueByKey reads a key-value pairs from the specified cgroup file, +// and returns a value of the specified key. ParseUint is used for value +// conversion. +func GetValueByKey(path, file, key string) (uint64, error) { + content, err := cgroups.ReadFile(path, file) + if err != nil { + return 0, err + } + + lines := strings.Split(content, "\n") + for _, line := range lines { + arr := strings.Split(line, " ") + if len(arr) == 2 && arr[0] == key { + val, err := ParseUint(arr[1], 10, 64) + if err != nil { + err = &ParseError{Path: path, File: file, Err: err} + } + return val, err + } + } + + return 0, nil +} + +// GetCgroupParamUint reads a single uint64 value from the specified cgroup file. +// If the value read is "max", the math.MaxUint64 is returned. +func GetCgroupParamUint(path, file string) (uint64, error) { + contents, err := GetCgroupParamString(path, file) + if err != nil { + return 0, err + } + contents = strings.TrimSpace(contents) + if contents == "max" { + return math.MaxUint64, nil + } + + res, err := ParseUint(contents, 10, 64) + if err != nil { + return res, &ParseError{Path: path, File: file, Err: err} + } + return res, nil +} + +// GetCgroupParamInt reads a single int64 value from specified cgroup file. +// If the value read is "max", the math.MaxInt64 is returned. +func GetCgroupParamInt(path, file string) (int64, error) { + contents, err := cgroups.ReadFile(path, file) + if err != nil { + return 0, err + } + contents = strings.TrimSpace(contents) + if contents == "max" { + return math.MaxInt64, nil + } + + res, err := strconv.ParseInt(contents, 10, 64) + if err != nil { + return res, &ParseError{Path: path, File: file, Err: err} + } + return res, nil +} + +// GetCgroupParamString reads a string from the specified cgroup file. +func GetCgroupParamString(path, file string) (string, error) { + contents, err := cgroups.ReadFile(path, file) + if err != nil { + return "", err + } + + return strings.TrimSpace(contents), nil +} |