From 0e3968af0b537eb7c98fad2ab83120028ff69015 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tam=C3=A1s=20B=C3=A1lint=20Misius?= <lbphacker@gmail.com>
Date: Tue, 9 May 2023 22:31:12 +0200
Subject: [PATCH] Add fs.isLink

---
 src/common/platform/Platform.h  |  1 +
 src/common/platform/Posix.cpp   | 20 ++++++++++++++++++++
 src/common/platform/Windows.cpp | 32 ++++++++++++++++++++++++++------
 src/lua/LuaScriptInterface.cpp  |  9 +++++++++
 4 files changed, 56 insertions(+), 6 deletions(-)

diff --git a/src/common/platform/Platform.h b/src/common/platform/Platform.h
index 591fe7a35..9016cd3c2 100644
--- a/src/common/platform/Platform.h
+++ b/src/common/platform/Platform.h
@@ -17,6 +17,7 @@ namespace Platform
 	bool Stat(ByteString filename);
 	bool FileExists(ByteString filename);
 	bool DirectoryExists(ByteString directory);
+	bool IsLink(ByteString path);
 	/**
 	 * @return true on success
 	 */
diff --git a/src/common/platform/Posix.cpp b/src/common/platform/Posix.cpp
index af18bbf09..b514ce991 100644
--- a/src/common/platform/Posix.cpp
+++ b/src/common/platform/Posix.cpp
@@ -82,6 +82,26 @@ bool DirectoryExists(ByteString directory)
 	}
 }
 
+bool IsLink(ByteString path)
+{
+	struct stat s;
+	if (stat(path.c_str(), &s) == 0)
+	{
+		if (s.st_mode & S_IFLNK)
+		{
+			return true; // Is path
+		}
+		else
+		{
+			return false; // Is file or something else
+		}
+	}
+	else
+	{
+		return false; // Doesn't exist
+	}
+}
+
 bool RemoveFile(ByteString filename)
 {
 	return remove(filename.c_str()) == 0;
diff --git a/src/common/platform/Windows.cpp b/src/common/platform/Windows.cpp
index 42864acb5..585af3a1d 100644
--- a/src/common/platform/Windows.cpp
+++ b/src/common/platform/Windows.cpp
@@ -11,18 +11,18 @@
 #include <shlwapi.h>
 #include <windows.h>
 #include <crtdbg.h>
+#include <memory>
 
 namespace Platform
 {
 ByteString GetCwd()
 {
 	ByteString cwd;
-	wchar_t *cwdPtr = _wgetcwd(NULL, 0);
+	auto cwdPtr = std::unique_ptr<wchar_t, decltype(&free)>(_wgetcwd(NULL, 0), free);
 	if (cwdPtr)
 	{
-		cwd = WinNarrow(cwdPtr);
+		cwd = WinNarrow(cwdPtr.get());
 	}
-	free(cwdPtr);
 	return cwd;
 }
 
@@ -47,7 +47,7 @@ long unsigned int GetTime()
 bool Stat(ByteString filename)
 {
 	struct _stat s;
-	if (_stat(filename.c_str(), &s) == 0)
+	if (_wstat(WinWiden(filename).c_str(), &s) == 0)
 	{
 		return true; // Something exists, be it a file, directory, link, etc.
 	}
@@ -60,7 +60,7 @@ bool Stat(ByteString filename)
 bool FileExists(ByteString filename)
 {
 	struct _stat s;
-	if (_stat(filename.c_str(), &s) == 0)
+	if (_wstat(WinWiden(filename).c_str(), &s) == 0)
 	{
 		if(s.st_mode & S_IFREG)
 		{
@@ -80,7 +80,7 @@ bool FileExists(ByteString filename)
 bool DirectoryExists(ByteString directory)
 {
 	struct _stat s;
-	if (_stat(directory.c_str(), &s) == 0)
+	if (_wstat(WinWiden(directory).c_str(), &s) == 0)
 	{
 		if(s.st_mode & S_IFDIR)
 		{
@@ -97,6 +97,26 @@ bool DirectoryExists(ByteString directory)
 	}
 }
 
+bool IsLink(ByteString path)
+{
+	struct _stat s;
+	if (_wstat(WinWiden(path).c_str(), &s) == 0)
+	{
+		if (GetFileAttributesW(WinWiden(path).c_str()) & FILE_ATTRIBUTE_REPARSE_POINT)
+		{
+			return true; // Is directory
+		}
+		else
+		{
+			return false; // Is file or something else
+		}
+	}
+	else
+	{
+		return false; // Doesn't exist
+	}
+}
+
 bool RemoveFile(ByteString filename)
 {
 	return _wremove(WinWiden(filename).c_str()) == 0;
diff --git a/src/lua/LuaScriptInterface.cpp b/src/lua/LuaScriptInterface.cpp
index 58fdb0dd3..23299cdc6 100644
--- a/src/lua/LuaScriptInterface.cpp
+++ b/src/lua/LuaScriptInterface.cpp
@@ -4002,6 +4002,14 @@ int LuaScriptInterface::graphics_setClipRect(lua_State * l)
 	return 4;
 }
 
+static int fsIsLink(lua_State * l)
+{
+	auto dirname = tpt_lua_checkByteString(l, 1);
+	bool ret = Platform::IsLink(dirname);
+	lua_pushboolean(l, ret);
+	return 1;
+}
+
 void LuaScriptInterface::initFileSystemAPI()
 {
 	//Methods
@@ -4010,6 +4018,7 @@ void LuaScriptInterface::initFileSystemAPI()
 		{"exists", fileSystem_exists},
 		{"isFile", fileSystem_isFile},
 		{"isDirectory", fileSystem_isDirectory},
+		{"isLink", fsIsLink},
 		{"makeDirectory", fileSystem_makeDirectory},
 		{"removeDirectory", fileSystem_removeDirectory},
 		{"removeFile", fileSystem_removeFile},