From 65aa53fc52ff15efe54df4147564828d535837f8 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 11 Oct 2024 12:27:00 +0200 Subject: Adding upstream version 8.0.3. Signed-off-by: Daniel Baumann --- modules/git/object_id.go | 114 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 modules/git/object_id.go (limited to 'modules/git/object_id.go') diff --git a/modules/git/object_id.go b/modules/git/object_id.go new file mode 100644 index 00000000..ecbc1587 --- /dev/null +++ b/modules/git/object_id.go @@ -0,0 +1,114 @@ +// Copyright 2023 The Gitea Authors. All rights reserved. +// SPDX-License-Identifier: MIT + +package git + +import ( + "bytes" + "encoding/hex" + "fmt" +) + +type ObjectID interface { + String() string + IsZero() bool + RawValue() []byte + Type() ObjectFormat +} + +/* SHA1 */ +type Sha1Hash [20]byte + +func (h *Sha1Hash) String() string { + return hex.EncodeToString(h[:]) +} + +func (h *Sha1Hash) IsZero() bool { + empty := Sha1Hash{} + return bytes.Equal(empty[:], h[:]) +} +func (h *Sha1Hash) RawValue() []byte { return h[:] } +func (*Sha1Hash) Type() ObjectFormat { return Sha1ObjectFormat } + +var _ ObjectID = &Sha1Hash{} + +func MustIDFromString(hexHash string) ObjectID { + id, err := NewIDFromString(hexHash) + if err != nil { + panic(err) + } + return id +} + +/* SHA256 */ +type Sha256Hash [32]byte + +func (h *Sha256Hash) String() string { + return hex.EncodeToString(h[:]) +} + +func (h *Sha256Hash) IsZero() bool { + empty := Sha256Hash{} + return bytes.Equal(empty[:], h[:]) +} +func (h *Sha256Hash) RawValue() []byte { return h[:] } +func (*Sha256Hash) Type() ObjectFormat { return Sha256ObjectFormat } + +/* utility */ +func NewIDFromString(hexHash string) (ObjectID, error) { + var theObjectFormat ObjectFormat + for _, objectFormat := range SupportedObjectFormats { + if len(hexHash) == objectFormat.FullLength() { + theObjectFormat = objectFormat + break + } + } + + if theObjectFormat == nil { + return nil, fmt.Errorf("length %d has no matched object format: %s", len(hexHash), hexHash) + } + + b, err := hex.DecodeString(hexHash) + if err != nil { + return nil, err + } + + if len(b) != theObjectFormat.FullLength()/2 { + return theObjectFormat.EmptyObjectID(), fmt.Errorf("length must be %d: %v", theObjectFormat.FullLength(), b) + } + return theObjectFormat.MustID(b), nil +} + +// IsEmptyCommitID checks if an hexadecimal string represents an empty commit according to git (only '0'). +// If objectFormat is not nil, the length will be checked as well (otherwise the length must match the sha1 or sha256 length). +func IsEmptyCommitID(commitID string, objectFormat ObjectFormat) bool { + if commitID == "" { + return true + } + if objectFormat == nil { + if Sha1ObjectFormat.FullLength() != len(commitID) && Sha256ObjectFormat.FullLength() != len(commitID) { + return false + } + } else if objectFormat.FullLength() != len(commitID) { + return false + } + for _, c := range commitID { + if c != '0' { + return false + } + } + return true +} + +// ComputeBlobHash compute the hash for a given blob content +func ComputeBlobHash(hashType ObjectFormat, content []byte) ObjectID { + return hashType.ComputeHash(ObjectBlob, content) +} + +type ErrInvalidSHA struct { + SHA string +} + +func (err ErrInvalidSHA) Error() string { + return fmt.Sprintf("invalid sha: %s", err.SHA) +} -- cgit v1.2.3