From 763581c73b8ac8a61223459f75cbc4876be81ada Mon Sep 17 00:00:00 2001
From: Kayne Ruse <kayneruse@gmail.com>
Date: Wed, 7 Jun 2023 23:55:30 +1000
Subject: [PATCH] Added header-only parsing to the repl, read more

Also:

* Ensured TOY_VERSION_BUILD is consistent throughout the whole build
* Updated README.md
---
 README.md           |  9 +++++---
 repl/repl_main.c    | 10 ++++++--
 repl/repl_tools.c   | 56 +++++++++++++++++++++++++++++++++++++++++++++
 repl/repl_tools.h   |  1 +
 source/toy_common.c | 18 +++++++++++++++
 source/toy_common.h |  7 ++++--
 6 files changed, 94 insertions(+), 7 deletions(-)

diff --git a/README.md b/README.md
index ae13c78..bf41f88 100644
--- a/README.md
+++ b/README.md
@@ -4,9 +4,11 @@
 
 # Toy
 
-This is the Toy programming language interpreter, written in C.
+The Toy programming language is an imperative bytecode-intermediate embedded scripting language. It isn't intended to operate on its own, but rather as part of another program, the "host". This process is intended to allow a decent amount of easy customisation by the host's end user, by exposing logic in script files. Alternatively, binary files in a custom format can be used as well.
 
-Special thanks to http://craftinginterpreters.com/ for their fantastic book that set me on this path.
+The host will provide all of the extensions needed on a case-by-case basis. Script files have the `.toy` file extension, while binary files have the `.tb` file extension.
+
+This is the Toy programming language interpreter, written in C.
 
 # Nifty Features
 
@@ -14,7 +16,7 @@ Special thanks to http://craftinginterpreters.com/ for their fantastic book that
 * Bytecode intermediate compilation
 * Optional, but robust type system (including `opaque` for arbitrary data)
 * Functions and types are first-class citizens
-* Import external libraries
+* Import native libraries from the host
 * Fancy slice notation for strings, arrays and dictionaries
 * Can re-direct output, error and assertion failure messages
 * Open source under the zlib license
@@ -71,3 +73,4 @@ This source code is covered by the zlib license (see [LICENSE.md](LICENSE.md)).
 
 * Seth A. Robinson
 
+Special thanks to http://craftinginterpreters.com/ for their fantastic book that set me on this path.
\ No newline at end of file
diff --git a/repl/repl_main.c b/repl/repl_main.c
index 24f2c90..5d3a8c0 100644
--- a/repl/repl_main.c
+++ b/repl/repl_main.c
@@ -193,8 +193,14 @@ int main(int argc, const char* argv[]) {
 			return -1;
 		}
 
-		//run the binary file
-		Toy_runBinaryFile(Toy_commandLine.binaryfile);
+		if (Toy_commandLine.parseBytecodeHeader) {
+			//only parse the bytecode header
+			Toy_parseBinaryFileHeader(Toy_commandLine.binaryfile);
+		}
+		else {
+			//run the binary file
+			Toy_runBinaryFile(Toy_commandLine.binaryfile);
+		}
 
 		//lib cleanup
 		Toy_freeDriveSystem();
diff --git a/repl/repl_tools.c b/repl/repl_tools.c
index fd44bd7..63090f9 100644
--- a/repl/repl_tools.c
+++ b/repl/repl_tools.c
@@ -149,3 +149,59 @@ void Toy_runSourceFile(const char* fname) {
 	Toy_runSource(source);
 	free((void*)source);
 }
+
+//utils for debugging the header
+static unsigned char readByte(const unsigned char* tb, int* count) {
+	unsigned char ret = *(unsigned char*)(tb + *count);
+	*count += 1;
+	return ret;
+}
+
+static const char* readString(const unsigned char* tb, int* count) {
+	const unsigned char* ret = tb + *count;
+	*count += strlen((char*)ret) + 1; //+1 for null character
+	return (const char*)ret;
+}
+
+void Toy_parseBinaryFileHeader(const char* fname) {
+	size_t size = 0; //not used
+	const unsigned char* tb = Toy_readFile(fname, &size);
+	if (!tb || size < 4) {
+		return;
+	}
+
+	int count = 0;
+
+	//header section
+	const unsigned char major = readByte(tb, &count);
+	const unsigned char minor = readByte(tb, &count);
+	const unsigned char patch = readByte(tb, &count);
+
+	const char* build = readString(tb, &count);
+
+	printf("Toy Programming Language Interpreter Version %d.%d.%d (interpreter built on %s)\n\n", TOY_VERSION_MAJOR, TOY_VERSION_MINOR, TOY_VERSION_PATCH, TOY_VERSION_BUILD);
+
+	printf("Toy Programming Language Bytecode Version ");
+
+	//print the output
+	if (major == TOY_VERSION_MAJOR && minor == TOY_VERSION_MINOR && patch == TOY_VERSION_PATCH) {
+		printf("%d.%d.%d", major, minor, patch);
+	}
+	else {
+		printf(TOY_CC_FONT_YELLOW TOY_CC_BACK_BLACK "%d.%d.%d" TOY_CC_RESET, major, minor, patch);
+	}
+
+	printf(" (interpreter built on ");
+
+	if (strncmp(build, TOY_VERSION_BUILD, strlen(TOY_VERSION_BUILD)) == 0) {
+		printf("%s", build);
+	}
+	else {
+		printf(TOY_CC_FONT_YELLOW TOY_CC_BACK_BLACK "%s" TOY_CC_RESET, build);
+	}
+
+	printf(")\n");
+
+	//cleanup
+	free((void*)tb);
+}
\ No newline at end of file
diff --git a/repl/repl_tools.h b/repl/repl_tools.h
index 235cef8..5fda23e 100644
--- a/repl/repl_tools.h
+++ b/repl/repl_tools.h
@@ -12,3 +12,4 @@ void Toy_runBinaryFile(const char* fname);
 void Toy_runSource(const char* source);
 void Toy_runSourceFile(const char* fname);
 
+void Toy_parseBinaryFileHeader(const char* fname);
\ No newline at end of file
diff --git a/source/toy_common.c b/source/toy_common.c
index 1898dca..5005500 100644
--- a/source/toy_common.c
+++ b/source/toy_common.c
@@ -15,6 +15,12 @@ STATIC_ASSERT(sizeof(unsigned char) == 1);
 STATIC_ASSERT(sizeof(unsigned short) == 2);
 STATIC_ASSERT(sizeof(unsigned int) == 4);
 
+static const char* build = __DATE__ " " __TIME__;
+
+const char* Toy_private_version_build() {
+	return build;
+}
+
 #ifndef TOY_DISABLE_REPL
 
 //declare the singleton with default values
@@ -29,6 +35,7 @@ Toy_CommandLine Toy_commandLine = {
 	.source = NULL,
 	.initialfile = NULL,
 	.enablePrintNewline = true,
+	.parseBytecodeHeader = false,
 	.verbose = false
 };
 
@@ -89,6 +96,16 @@ void Toy_initCommandLine(int argc, const char* argv[]) {
 			continue;
 		}
 
+		if (!strcmp(argv[i], "-p")) {
+			Toy_commandLine.parseBytecodeHeader = true;
+
+			if (Toy_commandLine.binaryfile) {
+				Toy_commandLine.error = false;
+			}
+
+			continue;
+		}
+
 		if (!strcmp(argv[i], "-n")) {
 			Toy_commandLine.enablePrintNewline = false;
 			Toy_commandLine.error = false;
@@ -124,6 +141,7 @@ void Toy_helpCommandLine(int argc, const char* argv[]) {
 	printf("  -c, --compile filename\tParse and compile the specified source file into an output file.\n");
 	printf("  -o, --output outfile\t\tName of the output file built with --compile (default: out.tb).\n");
 	printf("  -t, --initial filename\tStart the repl as normal, after first running the given file.\n");
+	printf("  -p\t\t\t\tParse the given bytecode's header, then exit (requires file.tb).\n");
 	printf("  -n\t\t\t\tDisable the newline character at the end of the print statement.\n");
 }
 
diff --git a/source/toy_common.h b/source/toy_common.h
index 1e3cb1d..7cabfbe 100644
--- a/source/toy_common.h
+++ b/source/toy_common.h
@@ -6,8 +6,10 @@
 
 #define TOY_VERSION_MAJOR 1
 #define TOY_VERSION_MINOR 1
-#define TOY_VERSION_PATCH 4
-#define TOY_VERSION_BUILD __DATE__ " " __TIME__
+#define TOY_VERSION_PATCH 5
+#define TOY_VERSION_BUILD Toy_private_version_build()
+
+const char* Toy_private_version_build();
 
 //platform/compiler-specific instructions
 #if defined(__linux__) || defined(__MINGW32__) || defined(__GNUC__)
@@ -42,6 +44,7 @@ typedef struct {
 	char* source;
 	char* initialfile;
 	bool enablePrintNewline;
+	bool parseBytecodeHeader;
 	bool verbose;
 } Toy_CommandLine;