1 files changed, 339 insertions, 0 deletions
diff --git a/lib/xmalloc.c b/lib/xmalloc.c
new file mode 100644
index 0000000..993c1ee
--- /dev/null
+++ b/lib/xmalloc.c
@@ -0,0 +1,339 @@
+/* xmalloc.c -- malloc with out of memory checking
+
+   Copyright (C) 1990-2000, 2002-2006, 2008-2022 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+#define XALLOC_INLINE _GL_EXTERN_INLINE
+
+#include "xalloc.h"
+
+#include "ialloc.h"
+#include "intprops.h"
+#include "minmax.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+static void * _GL_ATTRIBUTE_PURE
+nonnull (void *p)
+{
+  if (!p)
+    xalloc_die ();
+  return p;
+}
+
+/* Allocate S bytes of memory dynamically, with error checking.  */
+
+void *
+xmalloc (size_t s)
+{
+  return nonnull (malloc (s));
+}
+
+void *
+ximalloc (idx_t s)
+{
+  return nonnull (imalloc (s));
+}
+
+char *
+xcharalloc (size_t n)
+{
+  return XNMALLOC (n, char);
+}
+
+/* Change the size of an allocated block of memory P to S bytes,
+   with error checking.  */
+
+void *
+xrealloc (void *p, size_t s)
+{
+  void *r = realloc (p, s);
+  if (!r && (!p || s))
+    xalloc_die ();
+  return r;
+}
+
+void *
+xirealloc (void *p, idx_t s)
+{
+  return nonnull (irealloc (p, s));
+}
+
+/* Change the size of an allocated block of memory P to an array of N
+   objects each of S bytes, with error checking.  */
+
+void *
+xreallocarray (void *p, size_t n, size_t s)
+{
+  void *r = reallocarray (p, n, s);
+  if (!r && (!p || (n && s)))
+    xalloc_die ();
+  return r;
+}
+
+void *
+xireallocarray (void *p, idx_t n, idx_t s)
+{
+  return nonnull (ireallocarray (p, n, s));
+}
+
+/* Allocate an array of N objects, each with S bytes of memory,
+   dynamically, with error checking.  S must be nonzero.  */
+
+void *
+xnmalloc (size_t n, size_t s)
+{
+  return xreallocarray (NULL, n, s);
+}
+
+void *
+xinmalloc (idx_t n, idx_t s)
+{
+  return xireallocarray (NULL, n, s);
+}
+
+/* If P is null, allocate a block of at least *PS bytes; otherwise,
+   reallocate P so that it contains more than *PS bytes.  *PS must be
+   nonzero unless P is null.  Set *PS to the new block's size, and
+   return the pointer to the new block.  *PS is never set to zero, and
+   the returned pointer is never null.  */
+
+void *
+x2realloc (void *p, size_t *ps)
+{
+  return x2nrealloc (p, ps, 1);
+}
+
+/* If P is null, allocate a block of at least *PN such objects;
+   otherwise, reallocate P so that it contains more than *PN objects
+   each of S bytes.  S must be nonzero.  Set *PN to the new number of
+   objects, and return the pointer to the new block.  *PN is never set
+   to zero, and the returned pointer is never null.
+
+   Repeated reallocations are guaranteed to make progress, either by
+   allocating an initial block with a nonzero size, or by allocating a
+   larger block.
+
+   In the following implementation, nonzero sizes are increased by a
+   factor of approximately 1.5 so that repeated reallocations have
+   O(N) overall cost rather than O(N**2) cost, but the
+   specification for this function does not guarantee that rate.
+
+   Here is an example of use:
+
+     int *p = NULL;
+     size_t used = 0;
+     size_t allocated = 0;
+
+     void
+     append_int (int value)
+       {
+         if (used == allocated)
+           p = x2nrealloc (p, &allocated, sizeof *p);
+         p[used++] = value;
+       }
+
+   This causes x2nrealloc to allocate a block of some nonzero size the
+   first time it is called.
+
+   To have finer-grained control over the initial size, set *PN to a
+   nonzero value before calling this function with P == NULL.  For
+   example:
+
+     int *p = NULL;
+     size_t used = 0;
+     size_t allocated = 0;
+     size_t allocated1 = 1000;
+
+     void
+     append_int (int value)
+       {
+         if (used == allocated)
+           {
+             p = x2nrealloc (p, &allocated1, sizeof *p);
+             allocated = allocated1;
+           }
+         p[used++] = value;
+       }
+
+   */
+
+void *
+x2nrealloc (void *p, size_t *pn, size_t s)
+{
+  size_t n = *pn;
+
+  if (! p)
+    {
+      if (! n)
+        {
+          /* The approximate size to use for initial small allocation
+             requests, when the invoking code specifies an old size of
+             zero.  This is the largest "small" request for the GNU C
+             library malloc.  */
+          enum { DEFAULT_MXFAST = 64 * sizeof (size_t) / 4 };
+
+          n = DEFAULT_MXFAST / s;
+          n += !n;
+        }
+    }
+  else
+    {
+      /* Set N = floor (1.5 * N) + 1 to make progress even if N == 0.  */
+      if (INT_ADD_WRAPV (n, (n >> 1) + 1, &n))
+        xalloc_die ();
+    }
+
+  p = xreallocarray (p, n, s);
+  *pn = n;
+  return p;
+}
+
+/* Grow PA, which points to an array of *PN items, and return the
+   location of the reallocated array, updating *PN to reflect its
+   new size.  The new array will contain at least N_INCR_MIN more
+   items, but will not contain more than N_MAX items total.
+   S is the size of each item, in bytes.
+
+   S and N_INCR_MIN must be positive.  *PN must be
+   nonnegative.  If N_MAX is -1, it is treated as if it were
+   infinity.
+
+   If PA is null, then allocate a new array instead of reallocating
+   the old one.
+
+   Thus, to grow an array A without saving its old contents, do
+   { free (A); A = xpalloc (NULL, &AITEMS, ...); }.  */
+
+void *
+xpalloc (void *pa, idx_t *pn, idx_t n_incr_min, ptrdiff_t n_max, idx_t s)
+{
+  idx_t n0 = *pn;
+
+  /* The approximate size to use for initial small allocation
+     requests.  This is the largest "small" request for the GNU C
+     library malloc.  */
+  enum { DEFAULT_MXFAST = 64 * sizeof (size_t) / 4 };
+
+  /* If the array is tiny, grow it to about (but no greater than)
+     DEFAULT_MXFAST bytes.  Otherwise, grow it by about 50%.
+     Adjust the growth according to three constraints: N_INCR_MIN,
+     N_MAX, and what the C language can represent safely.  */
+
+  idx_t n;
+  if (INT_ADD_WRAPV (n0, n0 >> 1, &n))
+    n = IDX_MAX;
+  if (0 <= n_max && n_max < n)
+    n = n_max;
+
+  /* NBYTES is of a type suitable for holding the count of bytes in an object.
+     This is typically idx_t, but it should be size_t on (theoretical?)
+     platforms where SIZE_MAX < IDX_MAX so xpalloc does not pass
+     values greater than SIZE_MAX to xrealloc.  */
+#if IDX_MAX <= SIZE_MAX
+  idx_t nbytes;
+#else
+  size_t nbytes;
+#endif
+  idx_t adjusted_nbytes
+    = (INT_MULTIPLY_WRAPV (n, s, &nbytes)
+       ? MIN (IDX_MAX, SIZE_MAX)
+       : nbytes < DEFAULT_MXFAST ? DEFAULT_MXFAST : 0);
+  if (adjusted_nbytes)
+    {
+      n = adjusted_nbytes / s;
+      nbytes = adjusted_nbytes - adjusted_nbytes % s;
+    }
+
+  if (! pa)
+    *pn = 0;
+  if (n - n0 < n_incr_min
+      && (INT_ADD_WRAPV (n0, n_incr_min, &n)
+          || (0 <= n_max && n_max < n)
+          || INT_MULTIPLY_WRAPV (n, s, &nbytes)))
+    xalloc_die ();
+  pa = xrealloc (pa, nbytes);
+  *pn = n;
+  return pa;
+}
+
+/* Allocate S bytes of zeroed memory dynamically, with error checking.
+   There's no need for xnzalloc (N, S), since it would be equivalent
+   to xcalloc (N, S).  */
+
+void *
+xzalloc (size_t s)
+{
+  return xcalloc (s, 1);
+}
+
+void *
+xizalloc (idx_t s)
+{
+  return xicalloc (s, 1);
+}
+
+/* Allocate zeroed memory for N elements of S bytes, with error
+   checking.  S must be nonzero.  */
+
+void *
+xcalloc (size_t n, size_t s)
+{
+  return nonnull (calloc (n, s));
+}
+
+void *
+xicalloc (idx_t n, idx_t s)
+{
+  return nonnull (icalloc (n, s));
+}
+
+/* Clone an object P of size S, with error checking.  There's no need
+   for xnmemdup (P, N, S), since xmemdup (P, N * S) works without any
+   need for an arithmetic overflow check.  */
+
+void *
+xmemdup (void const *p, size_t s)
+{
+  return memcpy (xmalloc (s), p, s);
+}
+
+void *
+ximemdup (void const *p, idx_t s)
+{
+  return memcpy (ximalloc (s), p, s);
+}
+
+/* Clone an object P of size S, with error checking.  Append
+   a terminating NUL byte.  */
+
+char *
+ximemdup0 (void const *p, idx_t s)
+{
+  char *result = ximalloc (s + 1);
+  result[s] = 0;
+  return memcpy (result, p, s);
+}
+
+/* Clone STRING.  */
+
+char *
+xstrdup (char const *string)
+{
+  return xmemdup (string, strlen (string) + 1);
+}