:D

.clang-format

+IndentWidth: 2
+AccessModifierOffset: -2
+UseTab: Never
+ColumnLimit: 0
+MaxEmptyLinesToKeep: 2
+NamespaceIndentation: All

.gitignore

+build
+crash-*

.vscode/settings.json

+{
+    "files.associations": {
+        "cstdlib": "cpp",
+        "*.tcc": "cpp",
+        "memory": "cpp",
+        "new": "cpp"
+    }
+}
\ No newline at end of file

CMakeLists.txt

+cmake_minimum_required(VERSION 2.8)
+
+project(fuzzing-example)
+
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c11 -Wall -Wextra")
+
+add_library(utility INTERFACE)
+target_include_directories(utility INTERFACE ${CMAKE_CURRENT_SOURCE_DIR})
+
+add_executable(main main.c)
+target_link_libraries(main utility)
+
+enable_testing()
+add_subdirectory(tests)

LICENSE

+MIT License
+
+Copyright (c) 2019-2020 ntnu-tdat3020
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

+# Fuzzing example
+
+## Prerequisites
+* Linux (preferably Arch Linux or an Arch Linux based distribution such as Manjaro) or MacOS
+* [juCi++](https://gitlab.com/cppit/jucipp)
+
+## Instructions using juCi++
+1. Clone this repository
+2. Run juCi++ with the following arguments from a terminal:
+    * Linux: `CC=clang juci fuzzing-example`
+    * MacOS: `CC=/usr/local/opt/llvm/bin/clang juci fuzzing-example`
+3. Open `tests/utility_fuzzer_test.c` and run using either:
+    * Compile and Run in the Project menu
+    * Start/Continue in the Debug menu
+
+## Instructions using a terminal on Linux
+```sh
+git clone https://gitlab.com/ntnu-tdat3020/fuzzing-example
+mkdir fuzzing-example/build
+cd fuzzing-example/build
+CC=clang cmake ..
+make
+./tests/utility_fuzzer_test -max_total_time=60  # Cancel fuzzing after 60 seconds
+```

main.c

+#include "utility.h"
+#include <stdio.h>
+#include <string.h>
+const char *replaceString(const char *line, size_t len);
+
+int main() {
+  const char *test = "hei&der<borte>!";
+  size_t size = strlen(test);
+  const char *res = replaceString(test, size);
+  printf("%s\n", res);
+  free(res);
+  return 0;
+}

tests/CMakeLists.txt

+add_executable(utility_test utility_test.c)
+target_link_libraries(utility_test utility)
+target_compile_options(utility_test PRIVATE -fsanitize=address)
+target_link_options(utility_test PRIVATE -fsanitize=address)
+add_test(NAME utility_test COMMAND utility_test)
+
+add_executable(utility_fuzzer_test utility_fuzzer_test.c)
+target_link_libraries(utility_fuzzer_test utility)
+target_compile_options(utility_fuzzer_test PRIVATE -fsanitize=address,fuzzer)
+target_link_options(utility_fuzzer_test PRIVATE -fsanitize=address,fuzzer)
+add_test(NAME utility_fuzzer_test COMMAND utility_fuzzer_test)

tests/utility_fuzzer_test.c

+#include "../utility.h"
+#include <stddef.h>
+#include <stdint.h>
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+  const char *test = replaceString((const char *)data, size);
+  free(test);
+  return 0;
+}

tests/utility_test.c

+#include "../utility.h"
+#include <assert.h>
+#include <string.h>
+
+int main() {
+  char *stringInput = "1 < 2 && 2 > 1";
+  char *stringResult = "1 &lt; 2 &amp;&amp; 2 &gt; 1";
+  char *actualResult = replaceString(stringInput, strlen(stringInput));
+  assert(actualResult == stringResult);
+  free(actualResult);
+}

utility.h

+#pragma once
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+const char *replaceString(const char *str, size_t len) {
+  char amp[5] = "&amp;";
+  char lt[4] = "&lt;";
+  char gt[4] = "&gt;";
+
+  char *res;
+  res = malloc(len * 5 + 1);
+  // printf("%s\n", strlen(res));
+  int k = 0;
+  for (size_t i = 0; i < len;) {
+    if (str[i] == '&') {
+      for (int j = 0; j < 5; j++, k++) {
+        res[k] = amp[j];
+      }
+      i++;
+    } else if (str[i] == '<') {
+      for (int j = 0; j < 4; j++, k++) {
+        res[k] = lt[j];
+      }
+      i++;
+    } else if (str[i] == '>') {
+      for (int j = 0; j < 4; j++, k++) {
+        res[k] = gt[j];
+      }
+      i++;
+    } else {
+      res[k] = str[i];
+      k++;
+      i++;
+    }
+  }
+  res = realloc(res, k);
+  return res;
+}
\ No newline at end of file