From 0f9fe1288f226b2c78c9ed000be74ccb678ffd3c Mon Sep 17 00:00:00 2001
From: Johannes Maier <johannes2.maier@tum.de>
Date: Fri, 5 Jan 2024 17:51:01 +0100
Subject: [PATCH] Add read of input program.

---
 .clang-format |  2 +-
 .gitignore    |  1 -
 vuln.c        | 67 +++++++++++++++++++++++++++++++++++++++++++++++++--
 3 files changed, 66 insertions(+), 4 deletions(-)

diff --git a/.clang-format b/.clang-format
index 1c31383..a8a9459 100644
--- a/.clang-format
+++ b/.clang-format
@@ -1,3 +1,3 @@
 BasedOnStyle: LLVM
 IndentWidth: 4
-ColumnLimit: 200
\ No newline at end of file
+ColumnLimit: 200
diff --git a/.gitignore b/.gitignore
index 1d18c39..2f58603 100644
--- a/.gitignore
+++ b/.gitignore
@@ -58,4 +58,3 @@ build
 
 /.idea
 /.vscode
-
diff --git a/vuln.c b/vuln.c
index f26b97c..9fcfc78 100644
--- a/vuln.c
+++ b/vuln.c
@@ -1,6 +1,69 @@
+#include <stdbool.h>
+#include <stdint.h>
 #include <stdio.h>
+#include <stdlib.h>
+
+#define MAX_PROGRAM_LEN 0x10000
+
+typedef enum Instruction : uint8_t { TODO } Instruction;
+
+Instruction *get_program(size_t *program_len) {
+    puts("Now to your next program: How long should it bee?");
+
+    size_t len;
+    char len_buf[0x10];
+    char *end_ptr;
+    do {
+        if (fgets(len_buf, sizeof(len_buf), stdin) == NULL) {
+            exit(EXIT_FAILURE);
+        }
+        len = strtoull(len_buf, &end_ptr, 0);
+
+        if (len_buf == end_ptr) {
+            puts("That's not a integer, come back when you passed elementary school!");
+            exit(EXIT_FAILURE);
+        }
+
+        if (len <= MAX_PROGRAM_LEN) {
+            break;
+        }
+
+        puts("Nah, that's to long. Let's try again.");
+
+    } while (true);
+
+    Instruction *program = malloc(len * sizeof(Instruction));
+
+    if (program == NULL) {
+        exit(EXIT_FAILURE);
+    }
+
+    if (fread(program, sizeof(Instruction), len, stdin) != len) {
+        puts("You did not enter as many instructions as you wanted. Learn counting, idiot!");
+        free(program);
+        exit(EXIT_FAILURE);
+    }
+
+    *program_len = len;
+    return program;
+}
+
+int run_jit(Instruction *program, size_t len) { return 0; }
 
 int main() {
-    printf("Hello, World!\n");
-    return 0;
+    // TODO: better pun, add reference to pop-culture
+    puts("Welcome to JIT-aaS (Just In Time - always a Surprise)");
+
+    Instruction *program;
+    size_t program_len;
+    int exit_code;
+
+    while (true) {
+        program = get_program(&program_len);
+
+        exit_code = run_jit(program, program_len);
+
+        printf("Your program exited with %d\n", exit_code);
+        free(program);
+    }
 }