From 3ba0bdf7084f3d8eb37c64f0872d4ed912edede8 Mon Sep 17 00:00:00 2001
From: NotDSF <67711164+NotDSF@users.noreply.github.com>
Date: Tue, 9 Nov 2021 22:54:53 +0000
Subject: [PATCH] Save bytecode to file through CLI (#170)

Using --compile=binary it's now possible to produce binary bytecode so that it can be compiled offline and loaded into the VM.
---
 CLI/Repl.cpp | 46 +++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 39 insertions(+), 7 deletions(-)

diff --git a/CLI/Repl.cpp b/CLI/Repl.cpp
index 323ab144..a5bd5737 100644
--- a/CLI/Repl.cpp
+++ b/CLI/Repl.cpp
@@ -13,6 +13,17 @@
 
 #include <memory>
 
+#ifdef _WIN32
+    #include <io.h>
+    #include <fcntl.h>
+#endif
+
+enum class CompileFormat
+{
+    Default,
+    Binary
+};
+
 static int lua_loadstring(lua_State* L)
 {
     size_t l = 0;
@@ -370,7 +381,7 @@ static void reportError(const char* name, const Luau::CompileError& error)
     report(name, error.getLocation(), "CompileError", error.what());
 }
 
-static bool compileFile(const char* name)
+static bool compileFile(const char* name, CompileFormat format)
 {
     std::optional<std::string> source = readFile(name);
     if (!source)
@@ -387,7 +398,20 @@ static bool compileFile(const char* name)
 
         Luau::compileOrThrow(bcb, *source);
 
-        printf("%s", bcb.dumpEverything().c_str());
+        switch (format)
+        {
+        case CompileFormat::Default:
+            printf("%s", bcb.dumpEverything().c_str());
+            break;
+        case CompileFormat::Binary:
+            #ifdef _WIN32
+                _setmode(_fileno(stdout), _O_BINARY);
+            #endif
+
+            std::string Bytecode = bcb.getBytecode();
+            fwrite(Bytecode.c_str(), 1, Bytecode.size(), stdout);
+            break;
+        }
 
         return true;
     }
@@ -412,7 +436,7 @@ static void displayHelp(const char* argv0)
     printf("\n");
     printf("Available modes:\n");
     printf("  omitted: compile and run input files one by one\n");
-    printf("  --compile: compile input files and output resulting bytecode\n");
+    printf("  --compile[=format]: compile input files and output resulting formatted bytecode (binary or text)\n");
     printf("\n");
     printf("Available options:\n");
     printf("  --profile[=N]: profile the code using N Hz sampling (default 10000) and output results to profile.out\n");
@@ -444,8 +468,16 @@ int main(int argc, char** argv)
         return 0;
     }
 
-    if (argc >= 2 && strcmp(argv[1], "--compile") == 0)
-    {
+
+    if (argc >= 2 && strncmp(argv[1], "--compile", strlen("--compile")) == 0)
+    {   
+        CompileFormat format = CompileFormat::Default;
+
+        if (strcmp(argv[1], "--compile=binary") == 0) 
+        {
+            format = CompileFormat::Binary;
+        }
+
         int failed = 0;
 
         for (int i = 2; i < argc; ++i)
@@ -457,12 +489,12 @@ int main(int argc, char** argv)
             {
                 traverseDirectory(argv[i], [&](const std::string& name) {
                     if (name.length() > 4 && name.rfind(".lua") == name.length() - 4)
-                        failed += !compileFile(name.c_str());
+                        failed += !compileFile(name.c_str(), format);
                 });
             }
             else
             {
-                failed += !compileFile(argv[i]);
+                failed += !compileFile(argv[i], format);
             }
         }