Test failed Ring allocation

4 files changed, 179 insertions, 19 deletions

diff --git a/meson.build b/meson.build
index 2da63a0..d967a42 100644
--- a/meson.build
+++ b/meson.build
@@ -244,7 +244,7 @@ if get_option('tests')
 
   foreach test : tests
     c_args = []
-    sources = ['test/@0@.c'.format(test)]
+    sources = files('test/@0@.c'.format(test), 'test/failing_allocator.c')
 
     if get_option('test_malloc') and host_machine.system() != 'windows'
       sources += ['test/test_malloc.c']
diff --git a/test/failing_allocator.c b/test/failing_allocator.c
new file mode 100644
index 0000000..bb569de
--- /dev/null
+++ b/test/failing_allocator.c
@@ -0,0 +1,94 @@
+/*
+  Copyright 2021 David Robillard <d@drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "failing_allocator.h"
+
+#include "zix/allocator.h"
+#include "zix/attributes.h"
+
+#include <stdbool.h>
+#include <stddef.h>
+
+static bool
+attempt(ZixFailingAllocatorState* const state)
+{
+  ++state->n_allocations;
+
+  if (!state->n_remaining) {
+    return false;
+  }
+
+  --state->n_remaining;
+  return true;
+}
+
+ZIX_MALLOC_FUNC
+static void*
+zix_failing_malloc(ZixAllocatorHandle* const handle, const size_t size)
+{
+  ZixFailingAllocatorState* const state = (ZixFailingAllocatorState*)handle;
+  const ZixAllocator* const       base  = zix_default_allocator();
+
+  return attempt(state) ? base->malloc(base->handle, size) : NULL;
+}
+
+ZIX_MALLOC_FUNC
+static void*
+zix_failing_calloc(ZixAllocatorHandle* const handle,
+                   const size_t              nmemb,
+                   const size_t              size)
+{
+  ZixFailingAllocatorState* const state = (ZixFailingAllocatorState*)handle;
+  const ZixAllocator* const       base  = zix_default_allocator();
+
+  return attempt(state) ? base->calloc(base->handle, nmemb, size) : NULL;
+}
+
+static void*
+zix_failing_realloc(ZixAllocatorHandle* const handle,
+                    void* const               ptr,
+                    const size_t              size)
+{
+  ZixFailingAllocatorState* const state = (ZixFailingAllocatorState*)handle;
+  const ZixAllocator* const       base  = zix_default_allocator();
+
+  return attempt(state) ? base->realloc(base->handle, ptr, size) : NULL;
+}
+
+static void
+zix_failing_free(ZixAllocatorHandle* const handle, void* const ptr)
+{
+  (void)handle;
+
+  const ZixAllocator* const base = zix_default_allocator();
+
+  base->free(base->handle, ptr);
+}
+
+ZIX_CONST_FUNC
+ZixAllocator
+zix_failing_allocator(ZixFailingAllocatorState* const state)
+{
+  const ZixAllocator failing_allocator = {
+    state,
+    zix_failing_malloc,
+    zix_failing_calloc,
+    zix_failing_realloc,
+    zix_failing_free,
+  };
+
+  return failing_allocator;
+}
diff --git a/test/failing_allocator.h b/test/failing_allocator.h
new file mode 100644
index 0000000..b9daf75
--- /dev/null
+++ b/test/failing_allocator.h
@@ -0,0 +1,33 @@
+/*
+  Copyright 2021 David Robillard <d@drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#ifndef ZIX_FAILING_ALLOCATOR_H
+#define ZIX_FAILING_ALLOCATOR_H
+
+#include "zix/allocator.h"
+
+#include <stddef.h>
+
+/// An allocator that fails after some number of successes for testing
+typedef struct {
+  size_t n_allocations; ///< The number of allocations that have been attempted
+  size_t n_remaining;   ///< The number of remaining successful allocations
+} ZixFailingAllocatorState;
+
+ZixAllocator
+zix_failing_allocator(ZixFailingAllocatorState* state);
+
+#endif // ZIX_FAILING_ALLOCATOR_H
diff --git a/test/ring_test.c b/test/ring_test.c
index 23c5adc..2b20822 100644
--- a/test/ring_test.c
+++ b/test/ring_test.c
@@ -1,5 +1,5 @@
 /*
-  Copyright 2011-2020 David Robillard <d@drobilla.net>
+  Copyright 2011-2021 David Robillard <d@drobilla.net>
 
   Permission to use, copy, modify, and/or distribute this software for any
   purpose with or without fee is hereby granted, provided that the above
@@ -14,6 +14,11 @@
   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
 
+#undef NDEBUG
+
+#include "failing_allocator.h"
+
+#include "zix/allocator.h"
 #include "zix/attributes.h"
 #include "zix/ring.h"
 #include "zix/thread.h"
@@ -112,24 +117,9 @@ writer(void* ZIX_UNUSED(arg))
   return NULL;
 }
 
-int
-main(int argc, char** argv)
+static int
+test_ring(const unsigned size)
 {
-  if (argc > 1 && argv[1][0] == '-') {
-    printf("Usage: %s SIZE N_WRITES\n", argv[0]);
-    return 1;
-  }
-
-  unsigned size = 1024;
-  if (argc > 1) {
-    size = (unsigned)strtoul(argv[1], NULL, 10);
-  }
-
-  n_writes = size * 1024;
-  if (argc > 2) {
-    n_writes = (unsigned)strtoul(argv[2], NULL, 10);
-  }
-
   zix_ring_free(NULL);
 
   printf("Testing %u writes of %u ints to a %u int ring...\n",
@@ -239,3 +229,46 @@ main(int argc, char** argv)
   zix_ring_free(ring);
   return 0;
 }
+
+static void
+test_failed_alloc(void)
+{
+  ZixFailingAllocatorState state     = {0u, SIZE_MAX};
+  ZixAllocator             allocator = zix_failing_allocator(&state);
+
+  // Successfully allocate a ring to count the number of allocations
+  ring = zix_ring_new(&allocator, 512);
+  assert(ring);
+
+  // Test that each allocation failing is handled gracefully
+  const size_t n_new_allocs = state.n_allocations;
+  for (size_t i = 0u; i < n_new_allocs; ++i) {
+    state.n_remaining = i;
+    assert(!zix_ring_new(&allocator, 512));
+  }
+
+  zix_ring_free(ring);
+}
+
+int
+main(int argc, char** argv)
+{
+  if (argc > 1 && argv[1][0] == '-') {
+    printf("Usage: %s SIZE N_WRITES\n", argv[0]);
+    return 1;
+  }
+
+  unsigned size = 1024;
+  if (argc > 1) {
+    size = (unsigned)strtoul(argv[1], NULL, 10);
+  }
+
+  n_writes = size * 1024;
+  if (argc > 2) {
+    n_writes = (unsigned)strtoul(argv[2], NULL, 10);
+  }
+
+  test_failed_alloc();
+  test_ring(size);
+  return 0;
+}