llvm-project/compiler-rt/test/scudo/realloc.cpp

// RUN: %clang_scudo %s -o %t
// RUN:     %run %t pointers 2>&1
// RUN:     %run %t contents 2>&1
// RUN: not %run %t memalign 2>&1 | FileCheck %s

// Tests that our reallocation function returns the same pointer when the
// requested size can fit into the previously allocated chunk. Also tests that
// a new chunk is returned if the size is greater, and that the contents of the
// chunk are left unchanged.
// As a final test, make sure that a chunk allocated by memalign cannot be
// reallocated.

#include <assert.h>
#include <malloc.h>
#include <string.h>

int main(int argc, char **argv)
{
  void *p, *old_p;
  size_t size = 32;

  assert(argc == 2);
  if (!strcmp(argv[1], "pointers")) {
    old_p = p = realloc(nullptr, size);
    if (!p)
      return 1;
    size = malloc_usable_size(p);
    // Our realloc implementation will return the same pointer if the size
    // requested is lower or equal to the usable size of the associated chunk.
    p = realloc(p, size - 1);
    if (p != old_p)
      return 1;
    p = realloc(p, size);
    if (p != old_p)
      return 1;
    // And a new one if the size is greater.
    p = realloc(p, size + 1);
    if (p == old_p)
      return 1;
    // A size of 0 will free the chunk and return nullptr.
    p = realloc(p, 0);
    if (p)
      return 1;
    old_p = nullptr;
  }
  if (!strcmp(argv[1], "contents")) {
    p = realloc(nullptr, size);
    if (!p)
      return 1;
    for (int i = 0; i < size; i++)
      reinterpret_cast<char *>(p)[i] = 'A';
    p = realloc(p, size + 1);
    // The contents of the reallocated chunk must match the original one.
    for (int i = 0; i < size; i++)
      if (reinterpret_cast<char *>(p)[i] != 'A')
        return 1;
  }
  if (!strcmp(argv[1], "memalign")) {
    // A chunk coming from memalign cannot be reallocated.
    p = memalign(16, size);
    if (!p)
      return 1;
    p = realloc(p, size);
    free(p);
  }
  return 0;
}

// CHECK: ERROR: invalid chunk type when reallocating address