Moved drive system to repl, resolved #88

repl/toy_drive_system.c

@@ -0,0 +1,99 @@
+#include "toy_drive_system.h"
+
+#include "toy_memory.h"
+#include "toy_literal_dictionary.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+//file system API
+static Toy_LiteralDictionary driveDictionary;
+
+void Toy_initDriveSystem() {
+	Toy_initLiteralDictionary(&driveDictionary);
+}
+
+void Toy_freeDriveSystem() {
+	Toy_freeLiteralDictionary(&driveDictionary);
+}
+
+TOY_API void Toy_setDrivePath(char* drive, char* path) {
+	Toy_Literal driveLiteral = TOY_TO_STRING_LITERAL(Toy_createRefString(drive));
+	Toy_Literal pathLiteral = TOY_TO_STRING_LITERAL(Toy_createRefString(path));
+
+	Toy_setLiteralDictionary(&driveDictionary, driveLiteral, pathLiteral);
+
+	Toy_freeLiteral(driveLiteral);
+	Toy_freeLiteral(pathLiteral);
+}
+
+Toy_Literal Toy_getDrivePathLiteral(Toy_Interpreter* interpreter, Toy_Literal* drivePathLiteral) {
+	//check argument types
+	if (!TOY_IS_STRING(*drivePathLiteral)) {
+		interpreter->errorOutput("Incorrect argument type passed to Toy_getDrivePathLiteral\n");
+		return TOY_TO_NULL_LITERAL;
+	}
+
+	Toy_RefString* drivePath = Toy_copyRefString(TOY_AS_STRING(*drivePathLiteral));
+
+	//get the drive and path as a string (can't trust that pesky strtok - custom split) TODO: move this to refstring library
+	size_t driveLength = 0;
+	while (Toy_toCString(drivePath)[driveLength] != ':') {
+		if (driveLength >= Toy_lengthRefString(drivePath)) {
+			interpreter->errorOutput("Incorrect drive path format given to Toy_getDrivePathLiteral\n");
+
+			return TOY_TO_NULL_LITERAL;
+		}
+
+		driveLength++;
+	}
+
+	Toy_RefString* drive = Toy_createRefStringLength(Toy_toCString(drivePath), driveLength);
+	Toy_RefString* filePath = Toy_createRefStringLength( &Toy_toCString(drivePath)[driveLength + 1], Toy_lengthRefString(drivePath) - driveLength );
+
+	//get the real drive file path
+	Toy_Literal driveLiteral = TOY_TO_STRING_LITERAL(drive); //NOTE: driveLiteral takes ownership of the refString
+	Toy_Literal pathLiteral = Toy_getLiteralDictionary(&driveDictionary, driveLiteral);
+
+	if (!TOY_IS_STRING(pathLiteral)) {
+		interpreter->errorOutput("Incorrect literal type found for drive: ");
+		Toy_printLiteralCustom(pathLiteral, interpreter->errorOutput);
+		interpreter->errorOutput("\n");
+		Toy_freeLiteral(driveLiteral);
+		Toy_freeLiteral(pathLiteral);
+		Toy_deleteRefString(filePath);
+		Toy_deleteRefString(drivePath);
+
+		return TOY_TO_NULL_LITERAL;
+	}
+
+	//get the final real file path (concat) TODO: move this concat to refstring library
+	Toy_RefString* path = Toy_copyRefString(TOY_AS_STRING(pathLiteral));
+	size_t fileLength = Toy_lengthRefString(path) + Toy_lengthRefString(filePath);
+
+	char* file = TOY_ALLOCATE(char, fileLength + 1); //+1 for null
+	snprintf(file, fileLength, "%s%s", Toy_toCString(path), Toy_toCString(filePath));
+
+	//clean up the drive/path stuff
+    Toy_deleteRefString(drivePath);
+    Toy_deleteRefString(filePath);
+    Toy_deleteRefString(path);
+    Toy_freeLiteral(driveLiteral);
+	Toy_freeLiteral(pathLiteral);
+
+	//check for break-out attempts
+	for (size_t i = 0; i < fileLength - 1; i++) {
+		if (file[i] == '.' && file[i + 1] == '.') {
+			interpreter->errorOutput("Parent directory access not allowed\n");
+			TOY_FREE_ARRAY(char, file, fileLength + 1);
+			return TOY_TO_NULL_LITERAL;
+		}
+	}
+
+	Toy_Literal result = TOY_TO_STRING_LITERAL(Toy_createRefStringLength(file, fileLength));
+
+	TOY_FREE_ARRAY(char, file, fileLength + 1);
+
+	return result;
+}

repl/toy_drive_system.h

@@ -0,0 +1,76 @@
+#pragma once
+
+/*!
+# toy_drive_system.h
+
+When accessing the file system through toy (such as with the runner library), it's best practice to utilize Toy's built-in drive system - this system (tries to) prevent malicious accessing of files outside of the designated folders. It does this by causing an error when a script tries to access a parent directory.
+
+To use the drive system, first you must designate specific folders which can be accessed, like so:
+
+```c
+#include "toy_drive_system.h"
+
+int main(int argc, char* argv[]) {
+	//the drive system uses a LiteralDictionary, which must be initialized with this
+	Toy_initDriveSystem();
+
+	Toy_setDrivePath("scripts", "assets/scripts");
+	Toy_setDrivePath("sprites", "assets/sprites");
+	Toy_setDrivePath("fonts", "assets/fonts");
+
+	//TODO: do you stuff here
+
+	//clean up the drive dictionary when you're done
+	Toy_freeDriveSystem();
+
+	return 0;
+}
+```
+
+This utility is intended mainly for libraries to use - as such, the core of Toy does not utilize it.
+
+### Implementation Details
+
+The drive system uses a Toy's Dictionary structure to store the mappings between keys and values - this dictionary object is a static global which persists for the lifetime of the program.
+!*/
+
+#include "toy_common.h"
+
+#include "toy_literal.h"
+#include "toy_interpreter.h"
+
+/*!
+## Defined Functions
+!*/
+
+/*!
+### void Toy_initDriveSystem()
+
+This function initializes the drive system.
+!*/
+TOY_API void Toy_initDriveSystem();
+
+/*!
+### void Toy_freeDriveSystem()
+
+This function cleans up after the drive system is no longer needed.
+!*/
+TOY_API void Toy_freeDriveSystem();
+
+/*!
+### void Toy_setDrivePath(char* drive, char* path)
+
+This function sets a key-value pair in the drive system. It uses C strings, since its intended to be called directly from `main()`.
+!*/
+TOY_API void Toy_setDrivePath(char* drive, char* path);
+
+/*!
+### Toy_Literal Toy_getDrivePathLiteral(Toy_Interpreter* interpreter, Toy_Literal* drivePathLiteral)
+
+This function, when given a string literal of the correct format, will return a new string literal containing the relative filepath to a specified file.
+
+The correct format is `drive:/path/to/filename`, where `drive` is a drive that was specified with `Toy_setDrivePath()`.
+
+On failure, this function returns a null literal.
+!*/
+TOY_API Toy_Literal Toy_getDrivePathLiteral(Toy_Interpreter* interpreter, Toy_Literal* drivePathLiteral);