malloc: Improve aligned_alloc and calloc test coverage.

Add a DSO (malloc/tst-aligned_alloc-lib.so) that can be used during
testing to interpose malloc with a call that randomly uses either
aligned_alloc, __libc_malloc, or __libc_calloc in the place of malloc.
Use LD_PRELOAD with the DSO to mirror malloc/tst-malloc.c testing as an
example in malloc/tst-malloc-random.c.  Add malloc/tst-aligned-alloc-random.c
as another example that does a number of malloc calls with randomly sized,
but limited to 0xffff, requests.

The intention is to be able to utilize existing malloc testing to ensure
that similar allocation APIs are also exposed to the same rigors.

Reviewed-by: DJ Delorie <dj@redhat.com>

malloc/Makefile

@@ -27,6 +27,7 @@ headers := $(dist-headers) obstack.h mcheck.h
 tests := \
   mallocbug \
   tst-aligned-alloc \
+  tst-aligned-alloc-random \
   tst-alloc_buffer \
   tst-calloc \
   tst-free-errno \
@@ -36,6 +37,7 @@ tests := \
   tst-malloc-backtrace \
   tst-malloc-check \
   tst-malloc-fork-deadlock \
+  tst-malloc-random \
   tst-malloc-stats-cancellation \
   tst-malloc-tcache-leak \
   tst-malloc-thread-exit \
@@ -193,6 +195,7 @@ extra-libs-others = $(extra-libs)
 
 # Helper objects for some tests.
 extra-test-objs += \
+  tst-aligned_alloc-lib.so \
   tst-interpose-aux-nothread.o \
   tst-interpose-aux-thread.o \
 # extra-test-objs
@@ -202,6 +205,9 @@ test-extras = \
   tst-interpose-aux-thread \
 # test-extras
 
+modules-names = \
+  tst-aligned_alloc-lib
+
 libmemusage-routines = memusage
 libmemusage-inhibit-o = $(filter-out .os,$(object-suffixes))
 
@@ -408,3 +414,9 @@ tst-mallocstate-malloc-check-ENV = LD_PRELOAD=$(objpfx)libc_malloc_debug.so
 # libc_malloc_debug.so.
 $(objpfx)tst-mallocstate: $(objpfx)libc_malloc_debug.so
 $(objpfx)tst-mallocstate-malloc-check: $(objpfx)libc_malloc_debug.so
+
+$(objpfx)tst-aligned-alloc-random.out: $(objpfx)tst-aligned_alloc-lib.so
+$(objpfx)tst-malloc-random.out: $(objpfx)tst-aligned_alloc-lib.so
+
+tst-aligned-alloc-random-ENV = LD_PRELOAD=$(objpfx)tst-aligned_alloc-lib.so
+tst-malloc-random-ENV = LD_PRELOAD=$(objpfx)tst-aligned_alloc-lib.so

malloc/tst-aligned-alloc-random.c

@@ -0,0 +1,43 @@
+/* Test for randomized malloc that calls aligned_alloc
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <stdlib.h>
+#include <support/check.h>
+#include <time.h>
+
+static int
+do_test (void)
+{
+  void *p1;
+  int i;
+
+  srandom (time (NULL));
+
+  for (i = 0; i < 1024; i++)
+  {
+    size_t size = random () & 0xffff;
+
+    p1 = malloc (size);
+    TEST_VERIFY (p1 != NULL);
+  }
+
+  return 0;
+}
+
+
+#include <support/test-driver.c>

malloc/tst-aligned_alloc-lib.c

@@ -0,0 +1,72 @@
+/* Module used for improved aligned_alloc testing.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   Copyright The GNU Toolchain Authors.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public License as
+   published by the Free Software Foundation; either version 2.1 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If
+   not, see <https://www.gnu.org/licenses/>.  */
+
+#include <array_length.h>
+#include <libc-symbols.h>
+#include <stdlib.h>
+
+extern void *__libc_malloc (size_t size);
+extern void *__libc_calloc (size_t n, size_t size);
+
+int aligned_alloc_count = 0;
+int libc_malloc_count = 0;
+int libc_calloc_count = 0;
+
+/* Get a random alignment value.  Biased towards the smaller values.  Must be
+   a power of 2. */
+static size_t get_random_alignment (void)
+{
+  size_t aligns[] = {
+    1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384
+  };
+
+  return aligns[random () % array_length (aligns)];
+}
+
+static void *get_random_alloc (size_t size)
+{
+  void *retval;
+  size_t align;
+
+  switch (random() % 3)
+  {
+    case 1:
+      align = get_random_alignment ();
+      retval = aligned_alloc (align, size);
+      aligned_alloc_count++;
+      break;
+    case 2:
+      retval = __libc_calloc (1, size);
+      libc_calloc_count++;
+      break;
+    default:
+      retval = __libc_malloc (size);
+      libc_malloc_count++;
+      break;
+  }
+
+  return retval;
+}
+
+
+void * __random_malloc (size_t size)
+{
+  return get_random_alloc (size);
+}
+strong_alias (__random_malloc, malloc)

malloc/tst-malloc-random.c

@@ -0,0 +1,20 @@
+/* Test malloc with random calls to aligned_alloc and calloc.
+
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include "tst-malloc.c"

malloc/tst-malloc.c

@@ -18,7 +18,9 @@
 #include <errno.h>
 #include <malloc.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <libc-diag.h>
+#include <time.h>
 
 static int errors = 0;
 
@@ -35,6 +37,8 @@ do_test (void)
   void *p, *q;
   int save;
 
+  srandom (time (NULL));
+
   errno = 0;
 
   DIAG_PUSH_NEEDS_COMMENT;