Fix io.Reader implementations and wrap more errors

7 files changed, 80 insertions, 39 deletions

diff --git a/hotline/client_conn.go b/hotline/client_conn.go
index e21d8b1..c886dfc 100644
--- a/hotline/client_conn.go
+++ b/hotline/client_conn.go
@@ -81,7 +81,7 @@ func (cc *ClientConn) handleTransaction(transaction Transaction) error {
 
 		transactions, err := handler.Handler(cc, &transaction)
 		if err != nil {
-			return err
+			return fmt.Errorf("error handling transaction: %w", err)
 		}
 		for _, t := range transactions {
 			cc.Server.outbox <- t
diff --git a/hotline/file_header.go b/hotline/file_header.go
index 71a1c00..469f321 100644
--- a/hotline/file_header.go
+++ b/hotline/file_header.go
@@ -10,6 +10,8 @@ type FileHeader struct {
 	Size     [2]byte // Total size of FileHeader payload
 	Type     [2]byte // 0 for file, 1 for dir
 	FilePath []byte  // encoded file path
+
+	readOffset int // Internal offset to track read progress
 }
 
 func NewFileHeader(fileName string, isDir bool) FileHeader {
@@ -28,10 +30,18 @@ func NewFileHeader(fileName string, isDir bool) FileHeader {
 }
 
 func (fh *FileHeader) Read(p []byte) (int, error) {
-	return copy(p, slices.Concat(
+	buf := slices.Concat(
 		fh.Size[:],
 		fh.Type[:],
 		fh.FilePath,
-	),
-	), io.EOF
+	)
+
+	if fh.readOffset >= len(buf) {
+		return 0, io.EOF // All bytes have been read
+	}
+
+	n := copy(p, buf[fh.readOffset:])
+	fh.readOffset += n
+
+	return n, nil
 }
diff --git a/hotline/file_wrapper.go b/hotline/file_wrapper.go
index 997325a..342355b 100644
--- a/hotline/file_wrapper.go
+++ b/hotline/file_wrapper.go
@@ -246,7 +246,7 @@ func (f *fileWrapper) flattenedFileObject() (*flattenedFileObject, error) {
 
 		_, err = io.Copy(&f.ffo.FlatFileInformationFork, bytes.NewReader(b))
 		if err != nil {
-			return nil, err
+			return nil, fmt.Errorf("error copying FlatFileInformationFork: %w", err)
 		}
 
 	} else {
diff --git a/hotline/files.go b/hotline/files.go
index 0963fbf..901b98c 100644
--- a/hotline/files.go
+++ b/hotline/files.go
@@ -3,6 +3,7 @@ package hotline
 import (
 	"encoding/binary"
 	"errors"
+	"fmt"
 	"io"
 	"io/fs"
 	"os"
@@ -36,10 +37,11 @@ const maxFileSize = 4294967296
 func getFileNameList(path string, ignoreList []string) (fields []Field, err error) {
 	files, err := os.ReadDir(path)
 	if err != nil {
-		return fields, nil
+		return fields, fmt.Errorf("error reading path: %s: %w", path, err)
 	}
 
-	for _, file := range files {
+	for i, _ := range files {
+		file := files[i]
 		var fnwi FileNameWithInfo
 
 		if ignoreFile(file.Name(), ignoreList) {
@@ -50,14 +52,14 @@ func getFileNameList(path string, ignoreList []string) (fields []Field, err erro
 
 		fileInfo, err := file.Info()
 		if err != nil {
-			return fields, err
+			return fields, fmt.Errorf("error getting file info: %s: %w", file.Name(), err)
 		}
 
 		// Check if path is a symlink.  If so, follow it.
 		if fileInfo.Mode()&os.ModeSymlink != 0 {
 			resolvedPath, err := os.Readlink(filepath.Join(path, file.Name()))
 			if err != nil {
-				return fields, err
+				return fields, fmt.Errorf("error following symlink: %s: %w", resolvedPath, err)
 			}
 
 			rFile, err := os.Stat(resolvedPath)
@@ -92,7 +94,7 @@ func getFileNameList(path string, ignoreList []string) (fields []Field, err erro
 		} else if file.IsDir() {
 			dir, err := os.ReadDir(filepath.Join(path, file.Name()))
 			if err != nil {
-				return fields, err
+				return fields, fmt.Errorf("readDir: %w", err)
 			}
 
 			var c uint32
@@ -113,7 +115,7 @@ func getFileNameList(path string, ignoreList []string) (fields []Field, err erro
 
 			hlFile, err := newFileWrapper(&OSFileStore{}, path+"/"+file.Name(), 0)
 			if err != nil {
-				return nil, err
+				return nil, fmt.Errorf("newFileWrapper: %w", err)
 			}
 
 			copy(fnwi.FileSize[:], hlFile.totalSize())
@@ -135,7 +137,7 @@ func getFileNameList(path string, ignoreList []string) (fields []Field, err erro
 
 		b, err := io.ReadAll(&fnwi)
 		if err != nil {
-			return nil, err
+			return nil, fmt.Errorf("error io.ReadAll: %w", err)
 		}
 		fields = append(fields, NewField(FieldFileNameWithInfo, b))
 	}
diff --git a/hotline/flattened_file_object.go b/hotline/flattened_file_object.go
index 4bf8b4d..6419a1f 100644
--- a/hotline/flattened_file_object.go
+++ b/hotline/flattened_file_object.go
@@ -13,6 +13,8 @@ type flattenedFileObject struct {
 	FlatFileInformationFork       FlatFileInformationFork
 	FlatFileDataForkHeader        FlatFileForkHeader
 	FlatFileResForkHeader         FlatFileForkHeader
+
+	readOffset int // Internal offset to track read progress
 }
 
 // FlatFileHeader is the first section of a "Flattened File Object".  All fields have static values.
@@ -37,6 +39,8 @@ type FlatFileInformationFork struct {
 	Name             []byte // File name
 	CommentSize      []byte // Length of the comment
 	Comment          []byte // File comment
+
+	readOffset int // Internal offset to track read progress
 }
 
 func NewFlatFileInformationFork(fileName string, modifyTime []byte, typeSignature string, creatorSignature string) FlatFileInformationFork {
@@ -133,23 +137,30 @@ type FlatFileForkHeader struct {
 }
 
 func (ffif *FlatFileInformationFork) Read(p []byte) (int, error) {
-	return copy(p,
-		slices.Concat(
-			ffif.Platform,
-			ffif.TypeSignature,
-			ffif.CreatorSignature,
-			ffif.Flags,
-			ffif.PlatformFlags,
-			ffif.RSVD,
-			ffif.CreateDate,
-			ffif.ModifyDate,
-			ffif.NameScript,
-			ffif.ReadNameSize(),
-			ffif.Name,
-			ffif.CommentSize,
-			ffif.Comment,
-		),
-	), io.EOF
+	buf := slices.Concat(
+		ffif.Platform,
+		ffif.TypeSignature,
+		ffif.CreatorSignature,
+		ffif.Flags,
+		ffif.PlatformFlags,
+		ffif.RSVD,
+		ffif.CreateDate,
+		ffif.ModifyDate,
+		ffif.NameScript,
+		ffif.ReadNameSize(),
+		ffif.Name,
+		ffif.CommentSize,
+		ffif.Comment,
+	)
+
+	if ffif.readOffset >= len(buf) {
+		return 0, io.EOF // All bytes have been read
+	}
+
+	n := copy(p, buf[ffif.readOffset:])
+	ffif.readOffset += n
+
+	return n, nil
 }
 
 // Write implements the io.Writer interface for FlatFileInformationFork
@@ -173,7 +184,6 @@ func (ffif *FlatFileInformationFork) Write(p []byte) (int, error) {
 	if len(p) > int(total) {
 		ffif.CommentSize = p[total : total+2]
 		commentLen := binary.BigEndian.Uint16(ffif.CommentSize)
-
 		commentStartPos := int(total) + 2
 		commentEndPos := int(total) + 2 + int(commentLen)
 
@@ -182,7 +192,7 @@ func (ffif *FlatFileInformationFork) Write(p []byte) (int, error) {
 		total = uint16(commentEndPos)
 	}
 
-	return int(total), nil
+	return len(p), nil
 }
 
 func (ffif *FlatFileInformationFork) UnmarshalBinary(b []byte) error {
@@ -217,7 +227,7 @@ func (ffif *FlatFileInformationFork) UnmarshalBinary(b []byte) error {
 
 // Read implements the io.Reader interface for flattenedFileObject
 func (ffo *flattenedFileObject) Read(p []byte) (int, error) {
-	return copy(p, slices.Concat(
+	buf := slices.Concat(
 		ffo.FlatFileHeader.Format[:],
 		ffo.FlatFileHeader.Version[:],
 		ffo.FlatFileHeader.RSVD[:],
@@ -243,8 +253,16 @@ func (ffo *flattenedFileObject) Read(p []byte) (int, error) {
 		ffo.FlatFileDataForkHeader.CompressionType[:],
 		ffo.FlatFileDataForkHeader.RSVD[:],
 		ffo.FlatFileDataForkHeader.DataSize[:],
-	),
-	), io.EOF
+	)
+
+	if ffo.readOffset >= len(buf) {
+		return 0, io.EOF // All bytes have been read
+	}
+
+	n := copy(p, buf[ffo.readOffset:])
+	ffo.readOffset += n
+
+	return n, nil
 }
 
 func (ffo *flattenedFileObject) ReadFrom(r io.Reader) (int64, error) {
diff --git a/hotline/tracker.go b/hotline/tracker.go
index 6ee2a9f..8f8ddd1 100644
--- a/hotline/tracker.go
+++ b/hotline/tracker.go
@@ -18,6 +18,8 @@ type TrackerRegistration struct {
 	PassID      [4]byte // Random number generated by the server
 	Name        string  // Server Name
 	Description string  // Description of the server
+
+	readOffset int // Internal offset to track read progress
 }
 
 // Read implements io.Reader to write tracker registration payload bytes to slice
@@ -25,7 +27,7 @@ func (tr *TrackerRegistration) Read(p []byte) (int, error) {
 	userCount := make([]byte, 2)
 	binary.BigEndian.PutUint16(userCount, uint16(tr.UserCount))
 
-	return copy(p, slices.Concat(
+	buf := slices.Concat(
 		[]byte{0x00, 0x01}, // Magic number, always 1
 		tr.Port[:],
 		userCount,
@@ -35,7 +37,16 @@ func (tr *TrackerRegistration) Read(p []byte) (int, error) {
 		[]byte(tr.Name),
 		[]byte{uint8(len(tr.Description))},
 		[]byte(tr.Description),
-	)[:]), io.EOF
+	)
+
+	if tr.readOffset >= len(buf) {
+		return 0, io.EOF // All bytes have been read
+	}
+
+	n := copy(p, buf[tr.readOffset:])
+	tr.readOffset += n
+
+	return n, nil
 }
 
 func register(tracker string, tr *TrackerRegistration) error {
diff --git a/hotline/transaction_handlers.go b/hotline/transaction_handlers.go
index 2d4eabd..20b87e2 100644
--- a/hotline/transaction_handlers.go
+++ b/hotline/transaction_handlers.go
@@ -1763,13 +1763,13 @@ func HandleGetFileNameList(cc *ClientConn, t *Transaction) (res []Transaction, e
 		nil,
 	)
 	if err != nil {
-		return res, err
+		return res, fmt.Errorf("error reading file path: %w", err)
 	}
 
 	var fp FilePath
 	if t.GetField(FieldFilePath).Data != nil {
 		if _, err = fp.Write(t.GetField(FieldFilePath).Data); err != nil {
-			return res, err
+			return res, fmt.Errorf("error writing file path: %w", err)
 		}
 	}
 
@@ -1781,7 +1781,7 @@ func HandleGetFileNameList(cc *ClientConn, t *Transaction) (res []Transaction, e
 
 	fileNames, err := getFileNameList(fullPath, cc.Server.Config.IgnoreFiles)
 	if err != nil {
-		return res, err
+		return res, fmt.Errorf("getFileNameList: %w", err)
 	}
 
 	res = append(res, cc.NewReply(t, fileNames...))