From 8a8fe7b0e84495df1ff8d032efaf56ace88a3601 Mon Sep 17 00:00:00 2001
From: jakcron <jkrcarr@gmail.com>
Date: Sun, 15 Apr 2018 10:36:23 +0800
Subject: [PATCH] [fnd] Added IFile interface and SimpleFile implementation.

---
 lib/libfnd/include/fnd/IFile.h      | 14 +++++
 lib/libfnd/include/fnd/SimpleFile.h | 40 +++++++++++++
 lib/libfnd/source/SimpleFile.cpp    | 93 +++++++++++++++++++++++++++++
 3 files changed, 147 insertions(+)
 create mode 100644 lib/libfnd/include/fnd/IFile.h
 create mode 100644 lib/libfnd/include/fnd/SimpleFile.h
 create mode 100644 lib/libfnd/source/SimpleFile.cpp

diff --git a/lib/libfnd/include/fnd/IFile.h b/lib/libfnd/include/fnd/IFile.h
new file mode 100644
index 0000000..6a7cc56
--- /dev/null
+++ b/lib/libfnd/include/fnd/IFile.h
@@ -0,0 +1,14 @@
+#pragma once
+#include <fnd/types.h>
+
+namespace fnd
+{
+	class IFile
+	{
+	public:
+		virtual size_t size() = 0;
+		virtual void seek(size_t offset) = 0;
+		virtual void read(byte_t* out, size_t offset, size_t len) = 0;
+		virtual void write(const byte_t* out, size_t offset, size_t len) = 0;
+	};
+}
diff --git a/lib/libfnd/include/fnd/SimpleFile.h b/lib/libfnd/include/fnd/SimpleFile.h
new file mode 100644
index 0000000..bb25f7d
--- /dev/null
+++ b/lib/libfnd/include/fnd/SimpleFile.h
@@ -0,0 +1,40 @@
+#pragma once
+#include <fnd/IFile.h>
+#include <string>
+#include <cstdio>
+
+namespace fnd
+{
+	class SimpleFile : public IFile
+	{
+	public:
+		enum OpenMode
+		{
+			Read,
+			Edit,
+			Create
+		};
+
+		SimpleFile();
+		~SimpleFile();
+
+		void open(const std::string& path, OpenMode mode);
+		bool isOpen() const;
+		void close();
+		size_t size();
+		void seek(size_t offset);
+		size_t pos();
+		void read(byte_t* out, size_t offset, size_t len);
+		void write(const byte_t* out, size_t offset, size_t len);
+	
+	private:
+		const std::string kModuleName = "SimpleFile";
+
+		bool mOpen;
+		OpenMode mMode;
+		FILE* mFp;
+
+		const char* getOpenModeStr(OpenMode mMode);
+	};
+}
+
diff --git a/lib/libfnd/source/SimpleFile.cpp b/lib/libfnd/source/SimpleFile.cpp
new file mode 100644
index 0000000..bb907d3
--- /dev/null
+++ b/lib/libfnd/source/SimpleFile.cpp
@@ -0,0 +1,93 @@
+#include <fnd/SimpleFile.h>
+
+using namespace fnd;
+
+SimpleFile::SimpleFile() :
+	mOpen(false),
+	mMode(Read),
+	mFp(nullptr)
+{
+}
+
+SimpleFile::~SimpleFile()
+{
+	close();
+}
+
+void SimpleFile::open(const std::string& path, OpenMode mode)
+{
+	//close();
+	mMode = mode;
+	//printf("fopen(%s,%s);\n", path.c_str(), getOpenModeStr(mMode));
+	mFp = fopen(path.c_str(), getOpenModeStr(mMode));
+	if (mFp == nullptr)
+		throw fnd::Exception(kModuleName, "Failed to open file.");
+	mOpen = true;
+	seek(0);
+}
+
+bool SimpleFile::isOpen() const
+{
+	return mOpen == true && mFp != nullptr;
+}
+
+void SimpleFile::close()
+{
+	if (isOpen())
+	{
+		fclose(mFp);
+	}
+	mFp = nullptr;
+	mOpen = false;
+}
+
+size_t SimpleFile::size()
+{
+	size_t cur_pos = pos();
+	fseek(mFp, 0, SEEK_END);
+	size_t fsize = pos();
+	seek(cur_pos);
+	return fsize;
+}
+
+void SimpleFile::seek(size_t offset)
+{
+	fseek(mFp, offset, SEEK_SET);
+}
+
+size_t SimpleFile::pos()
+{
+	return ftell(mFp);
+}
+
+void SimpleFile::read(byte_t* out, size_t offset, size_t len)
+{
+	seek(offset);
+	fread(out, len, 1, mFp);
+}
+
+void SimpleFile::write(const byte_t* out, size_t offset, size_t len)
+{
+	seek(offset);
+	fwrite(out, len, 1, mFp);
+}
+
+const char* SimpleFile::getOpenModeStr(OpenMode mode)
+{
+	const char* str = "";
+	switch(mode)
+	{
+		case (Read):
+			str = "rb";
+			break;
+		case (Edit):
+			str = "rb+";
+			break;
+		case (Create):
+			str = "wb";
+			break;
+		default:
+			throw fnd::Exception(kModuleName, "Unknown open mode");
+	}
+	return str;
+}
\ No newline at end of file