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-rw-r--r--REORG.TODO/malloc/tst-mallocstate.c505
1 files changed, 505 insertions, 0 deletions
diff --git a/REORG.TODO/malloc/tst-mallocstate.c b/REORG.TODO/malloc/tst-mallocstate.c
new file mode 100644
index 0000000000..5cb39c0f3d
--- /dev/null
+++ b/REORG.TODO/malloc/tst-mallocstate.c
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+/* Emulate Emacs heap dumping to test malloc_set_state.
+   Copyright (C) 2001-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Wolfram Gloger <wg@malloc.de>, 2001.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <libc-symbols.h>
+#include <shlib-compat.h>
+
+#include "malloc.h"
+
+/* Make the compatibility symbols availabile to this test case.  */
+void *malloc_get_state (void);
+compat_symbol_reference (libc, malloc_get_state, malloc_get_state, GLIBC_2_0);
+int malloc_set_state (void *);
+compat_symbol_reference (libc, malloc_set_state, malloc_set_state, GLIBC_2_0);
+
+static int do_test (void);
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
+
+/* Maximum object size in the fake heap.  */
+enum { max_size = 64 };
+
+/* Allocation actions.  These are randomized actions executed on the
+   dumped heap (see allocation_tasks below).  They are interspersed
+   with operations on the new heap (see heap_activity).  */
+enum allocation_action
+  {
+    action_free,                /* Dumped and freed.  */
+    action_realloc,             /* Dumped and realloc'ed.  */
+    action_realloc_same,        /* Dumped and realloc'ed, same size.  */
+    action_realloc_smaller,     /* Dumped and realloc'ed, shrinked.  */
+    action_count
+  };
+
+/* Dumped heap.  Initialize it, so that the object is placed into the
+   .data section, for increased realism.  The size is an upper bound;
+   we use about half of the space.  */
+static size_t dumped_heap[action_count * max_size * max_size
+                          / sizeof (size_t)] = {1};
+
+/* Next free space in the dumped heap.  Also top of the heap at the
+   end of the initialization procedure.  */
+static size_t *next_heap_chunk;
+
+/* Copied from malloc.c and hooks.c.  The version is deliberately
+   lower than the final version of malloc_set_state.  */
+#define NBINS 128
+#define MALLOC_STATE_MAGIC   0x444c4541l
+#define MALLOC_STATE_VERSION (0 * 0x100l + 4l)
+static struct
+{
+  long magic;
+  long version;
+  void *av[NBINS * 2 + 2];
+  char *sbrk_base;
+  int sbrked_mem_bytes;
+  unsigned long trim_threshold;
+  unsigned long top_pad;
+  unsigned int n_mmaps_max;
+  unsigned long mmap_threshold;
+  int check_action;
+  unsigned long max_sbrked_mem;
+  unsigned long max_total_mem;
+  unsigned int n_mmaps;
+  unsigned int max_n_mmaps;
+  unsigned long mmapped_mem;
+  unsigned long max_mmapped_mem;
+  int using_malloc_checking;
+  unsigned long max_fast;
+  unsigned long arena_test;
+  unsigned long arena_max;
+  unsigned long narenas;
+} save_state =
+  {
+    .magic = MALLOC_STATE_MAGIC,
+    .version = MALLOC_STATE_VERSION,
+  };
+
+/* Allocate a blob in the fake heap.  */
+static void *
+dumped_heap_alloc (size_t length)
+{
+  /* malloc needs three state bits in the size field, so the minimum
+     alignment is 8 even on 32-bit architectures.  malloc_set_state
+     should be compatible with such heaps even if it currently
+     provides more alignment to applications.  */
+  enum
+  {
+    heap_alignment = 8,
+    heap_alignment_mask = heap_alignment - 1
+  };
+  _Static_assert (sizeof (size_t) <= heap_alignment,
+                  "size_t compatible with heap alignment");
+
+  /* Need at least this many bytes for metadata and application
+     data. */
+  size_t chunk_size = sizeof (size_t) + length;
+  /* Round up the allocation size to the heap alignment.  */
+  chunk_size += heap_alignment_mask;
+  chunk_size &= ~heap_alignment_mask;
+  if ((chunk_size & 3) != 0)
+    {
+      /* The lower three bits in the chunk size have to be 0.  */
+      write_message ("error: dumped_heap_alloc computed invalid chunk size\n");
+      _exit (1);
+    }
+  if (next_heap_chunk == NULL)
+    /* Initialize the top of the heap.  Add one word of zero padding,
+       to match existing practice.  */
+    {
+      dumped_heap[0] = 0;
+      next_heap_chunk = dumped_heap + 1;
+    }
+  else
+    /* The previous chunk is allocated. */
+    chunk_size |= 1;
+  *next_heap_chunk = chunk_size;
+
+  /* User data starts after the chunk header.  */
+  void *result = next_heap_chunk + 1;
+  next_heap_chunk += chunk_size / sizeof (size_t);
+
+  /* Mark the previous chunk as used.   */
+  *next_heap_chunk = 1;
+  return result;
+}
+
+/* Global seed variable for the random number generator.  */
+static unsigned long long global_seed;
+
+/* Simple random number generator.  The numbers are in the range from
+   0 to UINT_MAX (inclusive).  */
+static unsigned int
+rand_next (unsigned long long *seed)
+{
+  /* Linear congruential generated as used for MMIX.  */
+  *seed = *seed * 6364136223846793005ULL + 1442695040888963407ULL;
+  return *seed >> 32;
+}
+
+/* Fill LENGTH bytes at BUFFER with random contents, as determined by
+   SEED.  */
+static void
+randomize_buffer (unsigned char *buffer, size_t length,
+                  unsigned long long seed)
+{
+  for (size_t i = 0; i < length; ++i)
+    buffer[i] = rand_next (&seed);
+}
+
+/* Dumps the buffer to standard output,  in hexadecimal.  */
+static void
+dump_hex (unsigned char *buffer, size_t length)
+{
+  for (int i = 0; i < length; ++i)
+    printf (" %02X", buffer[i]);
+}
+
+/* Set to true if an error is encountered.  */
+static bool errors = false;
+
+/* Keep track of object allocations.  */
+struct allocation
+{
+  unsigned char *data;
+  unsigned int size;
+  unsigned int seed;
+};
+
+/* Check that the allocation task allocation has the expected
+   contents.  */
+static void
+check_allocation (const struct allocation *alloc, int index)
+{
+  size_t size = alloc->size;
+  if (alloc->data == NULL)
+    {
+      printf ("error: NULL pointer for allocation of size %zu at %d, seed %u\n",
+              size, index, alloc->seed);
+      errors = true;
+      return;
+    }
+
+  unsigned char expected[4096];
+  if (size > sizeof (expected))
+    {
+      printf ("error: invalid allocation size %zu at %d, seed %u\n",
+              size, index, alloc->seed);
+      errors = true;
+      return;
+    }
+  randomize_buffer (expected, size, alloc->seed);
+  if (memcmp (alloc->data, expected, size) != 0)
+    {
+      printf ("error: allocation %d data mismatch, size %zu, seed %u\n",
+              index, size, alloc->seed);
+      printf ("  expected:");
+      dump_hex (expected, size);
+      putc ('\n', stdout);
+      printf ("    actual:");
+      dump_hex (alloc->data, size);
+      putc ('\n', stdout);
+      errors = true;
+    }
+}
+
+/* A heap allocation combined with pending actions on it.  */
+struct allocation_task
+{
+  struct allocation allocation;
+  enum allocation_action action;
+};
+
+/* Allocation tasks.  Initialized by init_allocation_tasks and used by
+   perform_allocations.  */
+enum { allocation_task_count = action_count * max_size };
+static struct allocation_task allocation_tasks[allocation_task_count];
+
+/* Fisher-Yates shuffle of allocation_tasks.  */
+static void
+shuffle_allocation_tasks (void)
+{
+  for (int i = 0; i < allocation_task_count - 1; ++i)
+    {
+      /* Pick pair in the tail of the array.  */
+      int j = i + (rand_next (&global_seed)
+                   % ((unsigned) (allocation_task_count - i)));
+      if (j < 0 || j >= allocation_task_count)
+        {
+          write_message ("error: test bug in shuffle\n");
+          _exit (1);
+        }
+      /* Exchange. */
+      struct allocation_task tmp = allocation_tasks[i];
+      allocation_tasks[i] = allocation_tasks[j];
+      allocation_tasks[j] = tmp;
+    }
+}
+
+/* Set up the allocation tasks and the dumped heap.  */
+static void
+initial_allocations (void)
+{
+  /* Initialize in a position-dependent way.  */
+  for (int i = 0; i < allocation_task_count; ++i)
+    allocation_tasks[i] = (struct allocation_task)
+      {
+        .allocation =
+          {
+            .size = 1 + (i / action_count),
+            .seed = i,
+          },
+        .action = i % action_count
+      };
+
+  /* Execute the tasks in a random order.  */
+  shuffle_allocation_tasks ();
+
+  /* Initialize the contents of the dumped heap.   */
+  for (int i = 0; i < allocation_task_count; ++i)
+    {
+      struct allocation_task *task = allocation_tasks + i;
+      task->allocation.data = dumped_heap_alloc (task->allocation.size);
+      randomize_buffer (task->allocation.data, task->allocation.size,
+                        task->allocation.seed);
+    }
+
+  for (int i = 0; i < allocation_task_count; ++i)
+    check_allocation (&allocation_tasks[i].allocation, i);
+}
+
+/* Indicates whether init_heap has run.  This variable needs to be
+   volatile because malloc is declared __THROW, which implies it is a
+   leaf function, but we expect it to run our hooks.  */
+static volatile bool heap_initialized;
+
+/* Executed by glibc malloc, through __malloc_initialize_hook
+   below.  */
+static void
+init_heap (void)
+{
+  write_message ("info: performing heap initialization\n");
+  heap_initialized = true;
+
+  /* Populate the dumped heap.  */
+  initial_allocations ();
+
+  /* Complete initialization of the saved heap data structure.  */
+  save_state.sbrk_base = (void *) dumped_heap;
+  save_state.sbrked_mem_bytes = sizeof (dumped_heap);
+  /* Top pointer.  Adjust so that it points to the start of struct
+     malloc_chunk.  */
+  save_state.av[2] = (void *) (next_heap_chunk - 1);
+
+  /* Integrate the dumped heap into the process heap.  */
+  if (malloc_set_state (&save_state) != 0)
+    {
+      write_message ("error: malloc_set_state failed\n");
+      _exit (1);
+    }
+}
+
+/* Interpose the initialization callback.  */
+void (*volatile __malloc_initialize_hook) (void) = init_heap;
+
+/* Simulate occasional unrelated heap activity in the non-dumped
+   heap.  */
+enum { heap_activity_allocations_count = 32 };
+static struct allocation heap_activity_allocations
+  [heap_activity_allocations_count] = {};
+static int heap_activity_seed_counter = 1000 * 1000;
+
+static void
+heap_activity (void)
+{
+  /* Only do this from time to time.  */
+  if ((rand_next (&global_seed) % 4) == 0)
+    {
+      int slot = rand_next (&global_seed) % heap_activity_allocations_count;
+      struct allocation *alloc = heap_activity_allocations + slot;
+      if (alloc->data == NULL)
+        {
+          alloc->size = rand_next (&global_seed) % (4096U + 1);
+          alloc->data = xmalloc (alloc->size);
+          alloc->seed = heap_activity_seed_counter++;
+          randomize_buffer (alloc->data, alloc->size, alloc->seed);
+          check_allocation (alloc, 1000 + slot);
+        }
+      else
+        {
+          check_allocation (alloc, 1000 + slot);
+          free (alloc->data);
+          alloc->data = NULL;
+        }
+    }
+}
+
+static void
+heap_activity_deallocate (void)
+{
+  for (int i = 0; i < heap_activity_allocations_count; ++i)
+    free (heap_activity_allocations[i].data);
+}
+
+/* Perform a full heap check across the dumped heap allocation tasks,
+   and the simulated heap activity directly above.  */
+static void
+full_heap_check (void)
+{
+  /* Dumped heap.  */
+  for (int i = 0; i < allocation_task_count; ++i)
+    if (allocation_tasks[i].allocation.data != NULL)
+      check_allocation (&allocation_tasks[i].allocation, i);
+
+  /* Heap activity allocations.  */
+  for (int i = 0; i < heap_activity_allocations_count; ++i)
+    if (heap_activity_allocations[i].data != NULL)
+      check_allocation (heap_activity_allocations + i, i);
+}
+
+/* Used as an optimization barrier to force a heap allocation.  */
+__attribute__ ((noinline, noclone))
+static void
+my_free (void *ptr)
+{
+  free (ptr);
+}
+
+static int
+do_test (void)
+{
+  my_free (malloc (1));
+  if (!heap_initialized)
+    {
+      printf ("error: heap was not initialized by malloc\n");
+      return 1;
+    }
+
+  /* The first pass performs the randomly generated allocation
+     tasks.  */
+  write_message ("info: first pass through allocation tasks\n");
+  full_heap_check ();
+
+  /* Execute the post-undump tasks in a random order.  */
+  shuffle_allocation_tasks ();
+
+  for (int i = 0; i < allocation_task_count; ++i)
+    {
+      heap_activity ();
+      struct allocation_task *task = allocation_tasks + i;
+      switch (task->action)
+        {
+        case action_free:
+          check_allocation (&task->allocation, i);
+          free (task->allocation.data);
+          task->allocation.data = NULL;
+          break;
+
+        case action_realloc:
+          check_allocation (&task->allocation, i);
+          task->allocation.data = xrealloc
+            (task->allocation.data, task->allocation.size + max_size);
+          check_allocation (&task->allocation, i);
+          break;
+
+        case action_realloc_same:
+          check_allocation (&task->allocation, i);
+          task->allocation.data = xrealloc
+            (task->allocation.data, task->allocation.size);
+          check_allocation (&task->allocation, i);
+          break;
+
+        case action_realloc_smaller:
+          check_allocation (&task->allocation, i);
+          size_t new_size = task->allocation.size - 1;
+          task->allocation.data = xrealloc (task->allocation.data, new_size);
+          if (new_size == 0)
+            {
+              if (task->allocation.data != NULL)
+                {
+                  printf ("error: realloc with size zero did not deallocate\n");
+                  errors = true;
+                }
+              /* No further action on this task.  */
+              task->action = action_free;
+            }
+          else
+            {
+              task->allocation.size = new_size;
+              check_allocation (&task->allocation, i);
+            }
+          break;
+
+        case action_count:
+          abort ();
+        }
+      full_heap_check ();
+    }
+
+  /* The second pass frees the objects which were allocated during the
+     first pass.  */
+  write_message ("info: second pass through allocation tasks\n");
+
+  shuffle_allocation_tasks ();
+  for (int i = 0; i < allocation_task_count; ++i)
+    {
+      heap_activity ();
+      struct allocation_task *task = allocation_tasks + i;
+      switch (task->action)
+        {
+        case action_free:
+          /* Already freed, nothing to do.  */
+          break;
+
+        case action_realloc:
+        case action_realloc_same:
+        case action_realloc_smaller:
+          check_allocation (&task->allocation, i);
+          free (task->allocation.data);
+          task->allocation.data = NULL;
+          break;
+
+        case action_count:
+          abort ();
+        }
+      full_heap_check ();
+    }
+
+  heap_activity_deallocate ();
+
+  /* Check that the malloc_get_state stub behaves in the intended
+     way.  */
+  errno = 0;
+  if (malloc_get_state () != NULL)
+    {
+      printf ("error: malloc_get_state succeeded\n");
+      errors = true;
+    }
+  if (errno != ENOSYS)
+    {
+      printf ("error: malloc_get_state: %m\n");
+      errors = true;
+    }
+
+  return errors;
+}