go-mtree/check.go

214 lines
5.3 KiB
Go
Raw Normal View History

package mtree
import (
"fmt"
"os"
"sort"
"strings"
)
// Result of a Check
type Result struct {
// list of any failures in the Check
Failures []Failure `json:"failures"`
Missing []Entry `json:"missing,omitempty"`
Extra []Entry `json:"extra,omitempty"`
}
// Failure of a particular keyword for a path
type Failure struct {
Path string `json:"path"`
Keyword string `json:"keyword"`
Expected string `json:"expected"`
Got string `json:"got"`
}
// String returns a "pretty" formatting for a Failure
func (f Failure) String() string {
return fmt.Sprintf("%q: keyword %q: expected %s; got %s", f.Path, f.Keyword, f.Expected, f.Got)
}
// Check a root directory path against the DirectoryHierarchy, regarding only
// the available keywords from the list and each entry in the hierarchy.
// If keywords is nil, the check all present in the DirectoryHierarchy
func Check(root string, dh *DirectoryHierarchy, keywords []string) (*Result, error) {
creator := dhCreator{DH: dh}
curDir, err := os.Getwd()
if err == nil {
defer os.Chdir(curDir)
}
if err := os.Chdir(root); err != nil {
return nil, err
}
sort.Sort(byPos(creator.DH.Entries))
var result Result
for i, e := range creator.DH.Entries {
switch e.Type {
case SpecialType:
if e.Name == "/set" {
creator.curSet = &creator.DH.Entries[i]
} else if e.Name == "/unset" {
creator.curSet = nil
}
case RelativeType, FullType:
pathname, err := e.Path()
if err != nil {
return nil, err
}
info, err := os.Lstat(pathname)
if err != nil {
return nil, err
}
var kvs KeyVals
if creator.curSet != nil {
kvs = MergeSet(creator.curSet.Keywords, e.Keywords)
} else {
kvs = NewKeyVals(e.Keywords)
}
for _, kv := range kvs {
kw := kv.Keyword()
// 'tar_time' keyword evaluation wins against 'time' keyword evaluation
if kv.Keyword() == "time" && inSlice("tar_time", keywords) {
kw = "tar_time"
tartime := fmt.Sprintf("%s.%s", (strings.Split(kv.Value(), ".")[0]), "000000000")
kv = KeyVal(KeyVal(kw).ChangeValue(tartime))
}
keywordFunc, ok := KeywordFuncs[kw]
if !ok {
return nil, fmt.Errorf("Unknown keyword %q for file %q", kv.Keyword(), pathname)
}
if keywords != nil && !inSlice(kv.Keyword(), keywords) {
continue
}
fh, err := os.Open(pathname)
if err != nil {
return nil, err
}
curKeyVal, err := keywordFunc(pathname, info, fh)
if err != nil {
fh.Close()
return nil, err
}
fh.Close()
if string(kv) != curKeyVal {
failure := Failure{Path: pathname, Keyword: kv.Keyword(), Expected: kv.Value(), Got: KeyVal(curKeyVal).Value()}
result.Failures = append(result.Failures, failure)
}
}
}
}
return &result, nil
}
// TarCheck is the tar equivalent of checking a file hierarchy spec against a tar stream to
// determine if files have been changed.
func TarCheck(tarDH, dh *DirectoryHierarchy, keywords []string) (*Result, error) {
var result Result
var err error
var tarRoot *Entry
for _, e := range tarDH.Entries {
if e.Name == "." {
tarRoot = &e
break
}
}
if tarRoot == nil {
return nil, fmt.Errorf("root of archive could not be found")
}
tarRoot.Next = &Entry{
Name: "seen",
Type: CommentType,
}
curDir := tarRoot
creator := dhCreator{DH: dh}
sort.Sort(byPos(creator.DH.Entries))
var outOfTree bool
for i, e := range creator.DH.Entries {
switch e.Type {
case SpecialType:
if e.Name == "/set" {
creator.curSet = &creator.DH.Entries[i]
} else if e.Name == "/unset" {
creator.curSet = nil
}
case RelativeType, FullType:
pathname, err := e.Path()
if err != nil {
return nil, err
}
if outOfTree {
return &result, fmt.Errorf("No parent node from %s", pathname)
}
// TODO: handle the case where "." is not the first Entry to be found
tarEntry := curDir.Descend(e.Name)
if tarEntry == nil {
result.Missing = append(result.Missing, e)
continue
}
tarEntry.Next = &Entry{
Type: CommentType,
Name: "seen",
}
// expected values from file hierarchy spec
var kvs KeyVals
if creator.curSet != nil {
kvs = MergeSet(creator.curSet.Keywords, e.Keywords)
} else {
kvs = NewKeyVals(e.Keywords)
}
// actual
var tarkvs KeyVals
if tarEntry.Set != nil {
tarkvs = MergeSet(tarEntry.Set.Keywords, tarEntry.Keywords)
} else {
tarkvs = NewKeyVals(tarEntry.Keywords)
}
for _, kv := range kvs {
if _, ok := KeywordFuncs[kv.Keyword()]; !ok {
return nil, fmt.Errorf("Unknown keyword %q for file %q", kv.Keyword(), pathname)
}
if keywords != nil && !inSlice(kv.Keyword(), keywords) {
continue
}
tarpath, err := tarEntry.Path()
if err != nil {
return nil, err
}
if tarkv := tarkvs.Has(kv.Keyword()); tarkv != emptyKV {
if string(tarkv) != string(kv) {
failure := Failure{Path: tarpath, Keyword: kv.Keyword(), Expected: kv.Value(), Got: tarkv.Value()}
result.Failures = append(result.Failures, failure)
}
}
}
// Step into a directory
if tarEntry.Prev != nil {
curDir = tarEntry
}
case DotDotType:
if outOfTree {
return &result, fmt.Errorf("No parent node.")
}
curDir = curDir.Ascend()
if curDir == nil {
outOfTree = true
}
}
}
result.Extra = filter(tarRoot, func(e *Entry) bool {
return e.Next == nil
})
return &result, err
}