From 0489ae469ef96303ae85c34f8827a948a64901f8 Mon Sep 17 00:00:00 2001
From: Alex Yatskov <alex@foosoft.net>
Date: Sat, 15 Dec 2018 13:30:18 -0800
Subject: [PATCH] add simple stormlib wrapper

---
 formats/mpq/mpq.go | 164 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 164 insertions(+)
 create mode 100644 formats/mpq/mpq.go

diff --git a/formats/mpq/mpq.go b/formats/mpq/mpq.go
new file mode 100644
index 0000000..a3eee5d
--- /dev/null
+++ b/formats/mpq/mpq.go
@@ -0,0 +1,164 @@
+package mpq
+
+// #cgo LDFLAGS: -L./stormlib/ -lstorm -lz -lbz2 -lstdc++
+// #include <stdlib.h>
+// #define WINAPI
+// #define DWORD   		unsigned int
+// #define HANDLE  		void *
+// #define LPDWORD 		unsigned int *
+// #define LPOVERLAPPED void *
+// #define TCHAR   		char
+// #define bool    		unsigned char
+// bool  WINAPI SFileOpenArchive(const TCHAR * szMpqName, DWORD dwPriority, DWORD dwFlags, HANDLE * phMpq);
+// bool  WINAPI SFileCloseArchive(HANDLE hMpq);
+// bool  WINAPI SFileOpenFileEx(HANDLE hMpq, const char * szFileName, DWORD dwSearchScope, HANDLE * phFile);
+// DWORD WINAPI SFileGetFileSize(HANDLE hFile, LPDWORD pdwFileSizeHigh);
+// bool  WINAPI SFileReadFile(HANDLE hFile, void * lpBuffer, DWORD dwToRead, LPDWORD pdwRead, LPOVERLAPPED lpOverlapped);
+// bool  WINAPI SFileCloseFile(HANDLE hFile);
+// DWORD GetLastError();
+import "C"
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+	"strings"
+	"unsafe"
+)
+
+type File interface {
+	Read(data []byte) (int, error)
+	GetSize() (int, error)
+}
+
+type Archive interface {
+	OpenFile(path string) (File, error)
+	GetPaths() ([]string, error)
+	Close() error
+}
+
+func New(path string) (Archive, error) {
+	cs := C.CString(path)
+	defer C.free(unsafe.Pointer(cs))
+
+	a := new(archive)
+	if result := C.SFileOpenArchive(cs, 0, 0, &a.handle); result == 0 {
+		return nil, fmt.Errorf("failed to open archive (%d)", getLastError())
+	}
+
+	return a, nil
+}
+
+type file struct {
+	handle unsafe.Pointer
+	offset int
+	size   int
+}
+
+func (f *file) Read(data []byte) (int, error) {
+	size, err := f.GetSize()
+	if err != nil {
+		return 0, err
+	}
+
+	bytesRemaining := size - f.offset
+	if bytesRemaining == 0 {
+		return 0, io.EOF
+	}
+
+	bytesRequested := len(data)
+	if bytesRequested > bytesRemaining {
+		bytesRequested = bytesRemaining
+	}
+
+	var bytesRead int
+	if result := C.SFileReadFile(f.handle, unsafe.Pointer(&data[0]), C.unsigned(bytesRequested), (*C.unsigned)(unsafe.Pointer(&bytesRead)), nil); result == 0 {
+		return 0, fmt.Errorf("failed to read file (%d)", getLastError())
+	}
+
+	f.offset += bytesRead
+	return bytesRead, nil
+}
+
+func (f *file) GetSize() (int, error) {
+	if f.size != math.MaxUint32 {
+		return f.size, nil
+	}
+
+	size := int(C.SFileGetFileSize(f.handle, nil))
+	if size == -1 {
+		return 0, fmt.Errorf("failed to get file size (%d)", getLastError())
+	}
+
+	f.size = size
+	return size, nil
+}
+
+func (f *file) Close() error {
+	if result := C.SFileCloseFile(f.handle); result == 0 {
+		return fmt.Errorf("failed to close file (%d)", getLastError())
+	}
+
+	f.handle = nil
+	f.offset = 0
+	f.size = 0
+
+	return nil
+}
+
+type archive struct {
+	handle unsafe.Pointer
+	paths  []string
+}
+
+func (a *archive) Close() error {
+	if result := C.SFileCloseArchive(a.handle); result == 0 {
+		return fmt.Errorf("failed to close archive (%d)", getLastError())
+	}
+
+	a.handle = nil
+	a.paths = nil
+
+	return nil
+}
+
+func (a *archive) OpenFile(path string) (File, error) {
+	cs := C.CString(path)
+	defer C.free(unsafe.Pointer(cs))
+
+	file := &file{size: math.MaxUint32}
+	if result := C.SFileOpenFileEx(a.handle, cs, 0, &file.handle); result == 0 {
+		return nil, fmt.Errorf("failed to open file (%d)", getLastError())
+	}
+
+	return file, nil
+}
+
+func (a *archive) GetPaths() ([]string, error) {
+	if len(a.paths) > 0 {
+		return a.paths, nil
+	}
+
+	f, err := a.OpenFile("(listfile)")
+	if err != nil {
+		return nil, err
+	}
+
+	var buff bytes.Buffer
+	if _, err := io.Copy(&buff, f); err != nil {
+		return nil, err
+	}
+
+	for _, line := range strings.Split(string(buff.Bytes()), "\r\n") {
+		line = strings.TrimSpace(line)
+		if len(line) > 0 {
+			a.paths = append(a.paths, line)
+		}
+	}
+
+	return a.paths, nil
+}
+
+func getLastError() uint {
+	return uint(C.GetLastError())
+}