1 files changed, 69 insertions, 0 deletions
diff --git a/read_catblob.go b/read_catblob.go
new file mode 100644
index 0000000..ed5cb14
--- /dev/null
+++ b/read_catblob.go
@@ -0,0 +1,69 @@
+package libfastimport
+
+import (
+	"fmt"
+	"bytes"
+	"strconv"
+)
+
+func CatBlobParseGetMark(dat []byte) (string, error) {
+	if len(dat) != 41 {
+		return "", fmt.Errorf("get-mark: short <sha1>\\n: %q", string(dat))
+	}
+	if dat[40] != '\n' {
+		return "", fmt.Errorf("get-mark: malformed <sha1>\\n: %q", string(dat))
+	}
+	for _, b := range dat[:40] {
+		if !(('0' <= b && b <= '9') || ('a' <= b && b <= 'f')) {
+			return "", fmt.Errorf("get-mark: malformed <sha1>: %q", string(dat[:40]))
+		}
+	}
+	return string(dat[:40]), nil
+}
+
+func CatBlobParseCatBlob(full []byte) (sha1 string, data []byte, err error) {
+	// The format is:
+	//
+	//    <sha1> SP 'blob' SP <size> LF
+	//    <data> LF
+
+	lf := bytes.IndexByte(full, '\n')
+	if lf < 0 || lf == len(full)-1 {
+		return "", nil, fmt.Errorf("cat-blob: malformed header: %q", string(full))
+	}
+	head := full[:lf]
+	data = full[lf+1:len(full)-1]
+
+	if len(head) < 40+6+1 {
+		return "", nil, fmt.Errorf("cat-blob: malformed header: %q", string(head))
+	}
+
+	sha1 = string(head[:40])
+	for _, b := range sha1 {
+		if !(('0' <= b && b <= '9') || ('a' <= b && b <= 'f')) {
+			return "", nil, fmt.Errorf("cat-blob: malformed <sha1>: %q", sha1)
+		}
+	}
+
+	if string(head[40:46]) != " blob " {
+		return "", nil, fmt.Errorf("cat-blob: malformed header: %q", head)
+	}
+
+	size, err := strconv.Atoi(string(head[46:]))
+	if err != nil {
+		return "", nil, fmt.Errorf("cat-blob: malformed blob size: %v", err)
+	}
+
+	if size != len(data) {
+		return "", nil, fmt.Errorf("cat-blob: size header (%d) didn't match delivered size (%d)", size, len(data))
+	}
+
+	return sha1, data, err
+}
+
+func CatBlobParseLs(dataref string, path string) error {
+	//     <mode> SP ('blob' | 'tree' | 'commit') SP <dataref> HT <path> LF
+	// or
+	//     'missing' SP <path> LF
+	return nil // TODO
+}