Brainfuck emulator

C++/brainfuckemulator/.vscode/settings.json

@@ -0,0 +1,37 @@
+{
+    "files.associations": {
+        "fstream": "cpp",
+        "cctype": "cpp",
+        "clocale": "cpp",
+        "cmath": "cpp",
+        "cstddef": "cpp",
+        "cstdio": "cpp",
+        "cstdlib": "cpp",
+        "cwchar": "cpp",
+        "cwctype": "cpp",
+        "array": "cpp",
+        "*.tcc": "cpp",
+        "cstdint": "cpp",
+        "deque": "cpp",
+        "unordered_map": "cpp",
+        "vector": "cpp",
+        "exception": "cpp",
+        "initializer_list": "cpp",
+        "iosfwd": "cpp",
+        "iostream": "cpp",
+        "istream": "cpp",
+        "limits": "cpp",
+        "new": "cpp",
+        "optional": "cpp",
+        "ostream": "cpp",
+        "sstream": "cpp",
+        "stdexcept": "cpp",
+        "streambuf": "cpp",
+        "string_view": "cpp",
+        "system_error": "cpp",
+        "type_traits": "cpp",
+        "tuple": "cpp",
+        "typeinfo": "cpp",
+        "utility": "cpp"
+    }
+}

C++/brainfuckemulator/fml.bf

@@ -0,0 +1,2 @@
+>+++++++++[<++++++++>-]<.>+++++++[<++++>-]<+.+++++++..+++.>>>
+++++++++[<++++>-]<.>>>++++++++++[<+++++++++>-]<---.<<<<.+++.------.--------.>>+.

C++/brainfuckemulator/main.cpp

@@ -0,0 +1,87 @@
+#include <algorithm>
+#include <iostream>
+#include <fstream>
+#include <string>
+
+// > 	Increment the pointer.
+// < 	Decrement the pointer.
+// + 	Increment the byte at the pointer.
+// - 	Decrement the byte at the pointer.
+// . 	Output the byte at the pointer.
+// , 	Input a byte and store it in the byte at the pointer.
+// [ 	Jump forward past the matching ] if the byte at the pointer is zero.
+// ] 	Jump backward to the matching [ unless the byte at the pointer is zero.
+
+class BrainFuck {
+public:
+    char stack[30000];
+    int programCounter = 0;
+    char* ptr;
+    std::string program;
+
+    BrainFuck(std::string program) {
+        this->program = program;
+        this->ptr = (char*)this->program.c_str();
+    }
+
+    bool tick() {
+        if (programCounter >= 30000) return false;
+        int bal;
+        switch((char)program[programCounter]) {
+            case '>': ++ptr; break;
+            case '<': --ptr; break;
+            case '+': ++*ptr; break;
+            case '-': --*ptr; break;
+            case '.': programPrint(*ptr); break;
+            case ',': break; // TODO GETS();
+            case '[':   
+                        bal = 1;
+                        if (*ptr == '\0') {
+                            do {
+                                programCounter++;
+                                if (program[programCounter] == '[') bal++;
+                                else if (program[programCounter] == ']') bal--;
+                            } while (bal != 0);
+                        }
+                        break;
+            case ']':
+                        bal = 0;
+                        do {
+                            if (program[programCounter] == '[') bal++;
+                            else if (program[programCounter] == ']') bal--;
+                            programCounter--;
+                        } while (bal != 0);
+                        break;
+        }
+        programCounter++;
+        return true;
+    }
+
+    void programPrint(char toPrint) {
+        std::cout << "OUTPUT AT POSITION " << programCounter << ": ";
+        putchar(toPrint);
+        putchar('\n');
+    }
+};
+
+int main(int argc, char** argv) {
+    if (argc < 2) {std::cout << "No input file specified" << std::endl; exit(0); }
+    
+    std::ifstream input(*(argv + 1));
+    std::string programStream;
+
+    for (std::string line; std::getline(input, line); )
+        programStream += line;
+
+    programStream.erase(std::remove(programStream.begin(), programStream.end(), '\n'), programStream.end());
+
+    BrainFuck CPU(programStream);
+
+    while (1) {
+        if (!CPU.tick()) {
+            exit(0);
+        }
+    }
+
+    std::cout << programStream << std::endl;
+}