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-rw-r--r--gl/lib/malloc/dynarray-skeleton.c528
-rw-r--r--gl/lib/malloc/dynarray.h177
-rw-r--r--gl/lib/malloc/dynarray_at_failure.c40
-rw-r--r--gl/lib/malloc/dynarray_emplace_enlarge.c77
-rw-r--r--gl/lib/malloc/dynarray_finalize.c66
-rw-r--r--gl/lib/malloc/dynarray_resize.c68
-rw-r--r--gl/lib/malloc/dynarray_resize_clear.c39
-rw-r--r--gl/lib/malloc/scratch_buffer.h135
-rw-r--r--gl/lib/malloc/scratch_buffer_grow.c56
-rw-r--r--gl/lib/malloc/scratch_buffer_grow_preserve.c67
-rw-r--r--gl/lib/malloc/scratch_buffer_set_array_size.c64
11 files changed, 1317 insertions, 0 deletions
diff --git a/gl/lib/malloc/dynarray-skeleton.c b/gl/lib/malloc/dynarray-skeleton.c
new file mode 100644
index 0000000..580c278
--- /dev/null
+++ b/gl/lib/malloc/dynarray-skeleton.c
@@ -0,0 +1,528 @@
+/* Type-safe arrays which grow dynamically.
+ Copyright (C) 2017-2023 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/>. */
+
+/* Pre-processor macros which act as parameters:
+
+ DYNARRAY_STRUCT
+ The struct tag of dynamic array to be defined.
+ DYNARRAY_ELEMENT
+ The type name of the element type. Elements are copied
+ as if by memcpy, and can change address as the dynamic
+ array grows.
+ DYNARRAY_PREFIX
+ The prefix of the functions which are defined.
+
+ The following parameters are optional:
+
+ DYNARRAY_ELEMENT_FREE
+ DYNARRAY_ELEMENT_FREE (E) is evaluated to deallocate the
+ contents of elements. E is of type DYNARRAY_ELEMENT *.
+ DYNARRAY_ELEMENT_INIT
+ DYNARRAY_ELEMENT_INIT (E) is evaluated to initialize a new
+ element. E is of type DYNARRAY_ELEMENT *.
+ If DYNARRAY_ELEMENT_FREE but not DYNARRAY_ELEMENT_INIT is
+ defined, new elements are automatically zero-initialized.
+ Otherwise, new elements have undefined contents.
+ DYNARRAY_INITIAL_SIZE
+ The size of the statically allocated array (default:
+ at least 2, more elements if they fit into 128 bytes).
+ Must be a preprocessor constant. If DYNARRAY_INITIAL_SIZE is 0,
+ there is no statically allocated array at, and all non-empty
+ arrays are heap-allocated.
+ DYNARRAY_FINAL_TYPE
+ The name of the type which holds the final array. If not
+ defined, is PREFIX##finalize not provided. DYNARRAY_FINAL_TYPE
+ must be a struct type, with members of type DYNARRAY_ELEMENT and
+ size_t at the start (in this order).
+
+ These macros are undefined after this header file has been
+ included.
+
+ The following types are provided (their members are private to the
+ dynarray implementation):
+
+ struct DYNARRAY_STRUCT
+
+ The following functions are provided:
+
+ void DYNARRAY_PREFIX##init (struct DYNARRAY_STRUCT *);
+ void DYNARRAY_PREFIX##free (struct DYNARRAY_STRUCT *);
+ bool DYNARRAY_PREFIX##has_failed (const struct DYNARRAY_STRUCT *);
+ void DYNARRAY_PREFIX##mark_failed (struct DYNARRAY_STRUCT *);
+ size_t DYNARRAY_PREFIX##size (const struct DYNARRAY_STRUCT *);
+ DYNARRAY_ELEMENT *DYNARRAY_PREFIX##begin (const struct DYNARRAY_STRUCT *);
+ DYNARRAY_ELEMENT *DYNARRAY_PREFIX##end (const struct DYNARRAY_STRUCT *);
+ DYNARRAY_ELEMENT *DYNARRAY_PREFIX##at (struct DYNARRAY_STRUCT *, size_t);
+ void DYNARRAY_PREFIX##add (struct DYNARRAY_STRUCT *, DYNARRAY_ELEMENT);
+ DYNARRAY_ELEMENT *DYNARRAY_PREFIX##emplace (struct DYNARRAY_STRUCT *);
+ bool DYNARRAY_PREFIX##resize (struct DYNARRAY_STRUCT *, size_t);
+ void DYNARRAY_PREFIX##remove_last (struct DYNARRAY_STRUCT *);
+ void DYNARRAY_PREFIX##clear (struct DYNARRAY_STRUCT *);
+
+ The following functions are provided are provided if the
+ prerequisites are met:
+
+ bool DYNARRAY_PREFIX##finalize (struct DYNARRAY_STRUCT *,
+ DYNARRAY_FINAL_TYPE *);
+ (if DYNARRAY_FINAL_TYPE is defined)
+ DYNARRAY_ELEMENT *DYNARRAY_PREFIX##finalize (struct DYNARRAY_STRUCT *,
+ size_t *);
+ (if DYNARRAY_FINAL_TYPE is not defined)
+*/
+
+#include <malloc/dynarray.h>
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifndef DYNARRAY_STRUCT
+# error "DYNARRAY_STRUCT must be defined"
+#endif
+
+#ifndef DYNARRAY_ELEMENT
+# error "DYNARRAY_ELEMENT must be defined"
+#endif
+
+#ifndef DYNARRAY_PREFIX
+# error "DYNARRAY_PREFIX must be defined"
+#endif
+
+#ifdef DYNARRAY_INITIAL_SIZE
+# if DYNARRAY_INITIAL_SIZE < 0
+# error "DYNARRAY_INITIAL_SIZE must be non-negative"
+# endif
+# if DYNARRAY_INITIAL_SIZE > 0
+# define DYNARRAY_HAVE_SCRATCH 1
+# else
+# define DYNARRAY_HAVE_SCRATCH 0
+# endif
+#else
+/* Provide a reasonable default which limits the size of
+ DYNARRAY_STRUCT. */
+# define DYNARRAY_INITIAL_SIZE \
+ (sizeof (DYNARRAY_ELEMENT) > 64 ? 2 : 128 / sizeof (DYNARRAY_ELEMENT))
+# define DYNARRAY_HAVE_SCRATCH 1
+#endif
+
+/* Public type definitions. */
+
+/* All fields of this struct are private to the implementation. */
+struct DYNARRAY_STRUCT
+{
+ union
+ {
+ struct dynarray_header dynarray_abstract;
+ struct
+ {
+ /* These fields must match struct dynarray_header. */
+ size_t used;
+ size_t allocated;
+ DYNARRAY_ELEMENT *array;
+ } dynarray_header;
+ } u;
+
+#if DYNARRAY_HAVE_SCRATCH
+ /* Initial inline allocation. */
+ DYNARRAY_ELEMENT scratch[DYNARRAY_INITIAL_SIZE];
+#endif
+};
+
+/* Internal use only: Helper macros. */
+
+/* Ensure macro-expansion of DYNARRAY_PREFIX. */
+#define DYNARRAY_CONCAT0(prefix, name) prefix##name
+#define DYNARRAY_CONCAT1(prefix, name) DYNARRAY_CONCAT0(prefix, name)
+#define DYNARRAY_NAME(name) DYNARRAY_CONCAT1(DYNARRAY_PREFIX, name)
+
+/* Use DYNARRAY_FREE instead of DYNARRAY_NAME (free),
+ so that Gnulib does not change 'free' to 'rpl_free'. */
+#define DYNARRAY_FREE DYNARRAY_CONCAT1 (DYNARRAY_NAME (f), ree)
+
+/* Address of the scratch buffer if any. */
+#if DYNARRAY_HAVE_SCRATCH
+# define DYNARRAY_SCRATCH(list) (list)->scratch
+#else
+# define DYNARRAY_SCRATCH(list) NULL
+#endif
+
+/* Internal use only: Helper functions. */
+
+/* Internal function. Call DYNARRAY_ELEMENT_FREE with the array
+ elements. Name mangling needed due to the DYNARRAY_ELEMENT_FREE
+ macro expansion. */
+static inline void
+DYNARRAY_NAME (free__elements__) (DYNARRAY_ELEMENT *__dynarray_array,
+ size_t __dynarray_used)
+{
+#ifdef DYNARRAY_ELEMENT_FREE
+ for (size_t __dynarray_i = 0; __dynarray_i < __dynarray_used; ++__dynarray_i)
+ DYNARRAY_ELEMENT_FREE (&__dynarray_array[__dynarray_i]);
+#endif /* DYNARRAY_ELEMENT_FREE */
+}
+
+/* Internal function. Free the non-scratch array allocation. */
+static inline void
+DYNARRAY_NAME (free__array__) (struct DYNARRAY_STRUCT *list)
+{
+#if DYNARRAY_HAVE_SCRATCH
+ if (list->u.dynarray_header.array != list->scratch)
+ free (list->u.dynarray_header.array);
+#else
+ free (list->u.dynarray_header.array);
+#endif
+}
+
+/* Public functions. */
+
+/* Initialize a dynamic array object. This must be called before any
+ use of the object. */
+__attribute_nonnull__ ((1))
+static void
+DYNARRAY_NAME (init) (struct DYNARRAY_STRUCT *list)
+{
+ list->u.dynarray_header.used = 0;
+ list->u.dynarray_header.allocated = DYNARRAY_INITIAL_SIZE;
+ list->u.dynarray_header.array = DYNARRAY_SCRATCH (list);
+}
+
+/* Deallocate the dynamic array and its elements. */
+__attribute_maybe_unused__ __attribute_nonnull__ ((1))
+static void
+DYNARRAY_FREE (struct DYNARRAY_STRUCT *list)
+{
+ DYNARRAY_NAME (free__elements__)
+ (list->u.dynarray_header.array, list->u.dynarray_header.used);
+ DYNARRAY_NAME (free__array__) (list);
+ DYNARRAY_NAME (init) (list);
+}
+
+/* Return true if the dynamic array is in an error state. */
+__attribute_nonnull__ ((1))
+static inline bool
+DYNARRAY_NAME (has_failed) (const struct DYNARRAY_STRUCT *list)
+{
+ return list->u.dynarray_header.allocated == __dynarray_error_marker ();
+}
+
+/* Mark the dynamic array as failed. All elements are deallocated as
+ a side effect. */
+__attribute_nonnull__ ((1))
+static void
+DYNARRAY_NAME (mark_failed) (struct DYNARRAY_STRUCT *list)
+{
+ DYNARRAY_NAME (free__elements__)
+ (list->u.dynarray_header.array, list->u.dynarray_header.used);
+ DYNARRAY_NAME (free__array__) (list);
+ list->u.dynarray_header.array = DYNARRAY_SCRATCH (list);
+ list->u.dynarray_header.used = 0;
+ list->u.dynarray_header.allocated = __dynarray_error_marker ();
+}
+
+/* Return the number of elements which have been added to the dynamic
+ array. */
+__attribute_nonnull__ ((1))
+static inline size_t
+DYNARRAY_NAME (size) (const struct DYNARRAY_STRUCT *list)
+{
+ return list->u.dynarray_header.used;
+}
+
+/* Return a pointer to the array element at INDEX. Terminate the
+ process if INDEX is out of bounds. */
+__attribute_nonnull__ ((1))
+static inline DYNARRAY_ELEMENT *
+DYNARRAY_NAME (at) (struct DYNARRAY_STRUCT *list, size_t index)
+{
+ if (__glibc_unlikely (index >= DYNARRAY_NAME (size) (list)))
+ __libc_dynarray_at_failure (DYNARRAY_NAME (size) (list), index);
+ return list->u.dynarray_header.array + index;
+}
+
+/* Return a pointer to the first array element, if any. For a
+ zero-length array, the pointer can be NULL even though the dynamic
+ array has not entered the failure state. */
+__attribute_nonnull__ ((1))
+static inline DYNARRAY_ELEMENT *
+DYNARRAY_NAME (begin) (struct DYNARRAY_STRUCT *list)
+{
+ return list->u.dynarray_header.array;
+}
+
+/* Return a pointer one element past the last array element. For a
+ zero-length array, the pointer can be NULL even though the dynamic
+ array has not entered the failure state. */
+__attribute_nonnull__ ((1))
+static inline DYNARRAY_ELEMENT *
+DYNARRAY_NAME (end) (struct DYNARRAY_STRUCT *list)
+{
+ return list->u.dynarray_header.array + list->u.dynarray_header.used;
+}
+
+/* Internal function. Slow path for the add function below. */
+static void
+DYNARRAY_NAME (add__) (struct DYNARRAY_STRUCT *list, DYNARRAY_ELEMENT item)
+{
+ if (__glibc_unlikely
+ (!__libc_dynarray_emplace_enlarge (&list->u.dynarray_abstract,
+ DYNARRAY_SCRATCH (list),
+ sizeof (DYNARRAY_ELEMENT))))
+ {
+ DYNARRAY_NAME (mark_failed) (list);
+ return;
+ }
+
+ /* Copy the new element and increase the array length. */
+ list->u.dynarray_header.array[list->u.dynarray_header.used++] = item;
+}
+
+/* Add ITEM at the end of the array, enlarging it by one element.
+ Mark *LIST as failed if the dynamic array allocation size cannot be
+ increased. */
+__attribute_nonnull__ ((1))
+static inline void
+DYNARRAY_NAME (add) (struct DYNARRAY_STRUCT *list, DYNARRAY_ELEMENT item)
+{
+ /* Do nothing in case of previous error. */
+ if (DYNARRAY_NAME (has_failed) (list))
+ return;
+
+ /* Enlarge the array if necessary. */
+ if (__glibc_unlikely (list->u.dynarray_header.used
+ == list->u.dynarray_header.allocated))
+ {
+ DYNARRAY_NAME (add__) (list, item);
+ return;
+ }
+
+ /* Copy the new element and increase the array length. */
+ list->u.dynarray_header.array[list->u.dynarray_header.used++] = item;
+}
+
+/* Internal function. Building block for the emplace functions below.
+ Assumes space for one more element in *LIST. */
+static inline DYNARRAY_ELEMENT *
+DYNARRAY_NAME (emplace__tail__) (struct DYNARRAY_STRUCT *list)
+{
+ DYNARRAY_ELEMENT *result
+ = &list->u.dynarray_header.array[list->u.dynarray_header.used];
+ ++list->u.dynarray_header.used;
+#if defined (DYNARRAY_ELEMENT_INIT)
+ DYNARRAY_ELEMENT_INIT (result);
+#elif defined (DYNARRAY_ELEMENT_FREE)
+ memset (result, 0, sizeof (*result));
+#endif
+ return result;
+}
+
+/* Internal function. Slow path for the emplace function below. */
+static DYNARRAY_ELEMENT *
+DYNARRAY_NAME (emplace__) (struct DYNARRAY_STRUCT *list)
+{
+ if (__glibc_unlikely
+ (!__libc_dynarray_emplace_enlarge (&list->u.dynarray_abstract,
+ DYNARRAY_SCRATCH (list),
+ sizeof (DYNARRAY_ELEMENT))))
+ {
+ DYNARRAY_NAME (mark_failed) (list);
+ return NULL;
+ }
+ return DYNARRAY_NAME (emplace__tail__) (list);
+}
+
+/* Allocate a place for a new element in *LIST and return a pointer to
+ it. The pointer can be NULL if the dynamic array cannot be
+ enlarged due to a memory allocation failure. */
+__attribute_maybe_unused__ __attribute_warn_unused_result__
+__attribute_nonnull__ ((1))
+static
+/* Avoid inlining with the larger initialization code. */
+#if !(defined (DYNARRAY_ELEMENT_INIT) || defined (DYNARRAY_ELEMENT_FREE))
+inline
+#endif
+DYNARRAY_ELEMENT *
+DYNARRAY_NAME (emplace) (struct DYNARRAY_STRUCT *list)
+{
+ /* Do nothing in case of previous error. */
+ if (DYNARRAY_NAME (has_failed) (list))
+ return NULL;
+
+ /* Enlarge the array if necessary. */
+ if (__glibc_unlikely (list->u.dynarray_header.used
+ == list->u.dynarray_header.allocated))
+ return (DYNARRAY_NAME (emplace__) (list));
+ return DYNARRAY_NAME (emplace__tail__) (list);
+}
+
+/* Change the size of *LIST to SIZE. If SIZE is larger than the
+ existing size, new elements are added (which can be initialized).
+ Otherwise, the list is truncated, and elements are freed. Return
+ false on memory allocation failure (and mark *LIST as failed). */
+__attribute_maybe_unused__ __attribute_nonnull__ ((1))
+static bool
+DYNARRAY_NAME (resize) (struct DYNARRAY_STRUCT *list, size_t size)
+{
+ if (size > list->u.dynarray_header.used)
+ {
+ bool ok;
+#if defined (DYNARRAY_ELEMENT_INIT)
+ /* The new elements have to be initialized. */
+ size_t old_size = list->u.dynarray_header.used;
+ ok = __libc_dynarray_resize (&list->u.dynarray_abstract,
+ size, DYNARRAY_SCRATCH (list),
+ sizeof (DYNARRAY_ELEMENT));
+ if (ok)
+ for (size_t i = old_size; i < size; ++i)
+ {
+ DYNARRAY_ELEMENT_INIT (&list->u.dynarray_header.array[i]);
+ }
+#elif defined (DYNARRAY_ELEMENT_FREE)
+ /* Zero initialization is needed so that the elements can be
+ safely freed. */
+ ok = __libc_dynarray_resize_clear
+ (&list->u.dynarray_abstract, size,
+ DYNARRAY_SCRATCH (list), sizeof (DYNARRAY_ELEMENT));
+#else
+ ok = __libc_dynarray_resize (&list->u.dynarray_abstract,
+ size, DYNARRAY_SCRATCH (list),
+ sizeof (DYNARRAY_ELEMENT));
+#endif
+ if (__glibc_unlikely (!ok))
+ DYNARRAY_NAME (mark_failed) (list);
+ return ok;
+ }
+ else
+ {
+ /* The list has shrunk in size. Free the removed elements. */
+ DYNARRAY_NAME (free__elements__)
+ (list->u.dynarray_header.array + size,
+ list->u.dynarray_header.used - size);
+ list->u.dynarray_header.used = size;
+ return true;
+ }
+}
+
+/* Remove the last element of LIST if it is present. */
+__attribute_maybe_unused__ __attribute_nonnull__ ((1))
+static void
+DYNARRAY_NAME (remove_last) (struct DYNARRAY_STRUCT *list)
+{
+ /* used > 0 implies that the array is the non-failed state. */
+ if (list->u.dynarray_header.used > 0)
+ {
+ size_t new_length = list->u.dynarray_header.used - 1;
+#ifdef DYNARRAY_ELEMENT_FREE
+ DYNARRAY_ELEMENT_FREE (&list->u.dynarray_header.array[new_length]);
+#endif
+ list->u.dynarray_header.used = new_length;
+ }
+}
+
+/* Remove all elements from the list. The elements are freed, but the
+ list itself is not. */
+__attribute_maybe_unused__ __attribute_nonnull__ ((1))
+static void
+DYNARRAY_NAME (clear) (struct DYNARRAY_STRUCT *list)
+{
+ /* free__elements__ does nothing if the list is in the failed
+ state. */
+ DYNARRAY_NAME (free__elements__)
+ (list->u.dynarray_header.array, list->u.dynarray_header.used);
+ list->u.dynarray_header.used = 0;
+}
+
+#ifdef DYNARRAY_FINAL_TYPE
+/* Transfer the dynamic array to a permanent location at *RESULT.
+ Returns true on success on false on allocation failure. In either
+ case, *LIST is re-initialized and can be reused. A NULL pointer is
+ stored in *RESULT if LIST refers to an empty list. On success, the
+ pointer in *RESULT is heap-allocated and must be deallocated using
+ free. */
+__attribute_maybe_unused__ __attribute_warn_unused_result__
+__attribute_nonnull__ ((1, 2))
+static bool
+DYNARRAY_NAME (finalize) (struct DYNARRAY_STRUCT *list,
+ DYNARRAY_FINAL_TYPE *result)
+{
+ struct dynarray_finalize_result res;
+ if (__libc_dynarray_finalize (&list->u.dynarray_abstract,
+ DYNARRAY_SCRATCH (list),
+ sizeof (DYNARRAY_ELEMENT), &res))
+ {
+ /* On success, the result owns all the data. */
+ DYNARRAY_NAME (init) (list);
+ *result = (DYNARRAY_FINAL_TYPE) { res.array, res.length };
+ return true;
+ }
+ else
+ {
+ /* On error, we need to free all data. */
+ DYNARRAY_FREE (list);
+ errno = ENOMEM;
+ return false;
+ }
+}
+#else /* !DYNARRAY_FINAL_TYPE */
+/* Transfer the dynamic array to a heap-allocated array and return a
+ pointer to it. The pointer is NULL if memory allocation fails, or
+ if the array is empty, so this function should be used only for
+ arrays which are known not be empty (usually because they always
+ have a sentinel at the end). If LENGTHP is not NULL, the array
+ length is written to *LENGTHP. *LIST is re-initialized and can be
+ reused. */
+__attribute_maybe_unused__ __attribute_warn_unused_result__
+__attribute_nonnull__ ((1))
+static DYNARRAY_ELEMENT *
+DYNARRAY_NAME (finalize) (struct DYNARRAY_STRUCT *list, size_t *lengthp)
+{
+ struct dynarray_finalize_result res;
+ if (__libc_dynarray_finalize (&list->u.dynarray_abstract,
+ DYNARRAY_SCRATCH (list),
+ sizeof (DYNARRAY_ELEMENT), &res))
+ {
+ /* On success, the result owns all the data. */
+ DYNARRAY_NAME (init) (list);
+ if (lengthp != NULL)
+ *lengthp = res.length;
+ return res.array;
+ }
+ else
+ {
+ /* On error, we need to free all data. */
+ DYNARRAY_FREE (list);
+ errno = ENOMEM;
+ return NULL;
+ }
+}
+#endif /* !DYNARRAY_FINAL_TYPE */
+
+/* Undo macro definitions. */
+
+#undef DYNARRAY_CONCAT0
+#undef DYNARRAY_CONCAT1
+#undef DYNARRAY_NAME
+#undef DYNARRAY_SCRATCH
+#undef DYNARRAY_HAVE_SCRATCH
+
+#undef DYNARRAY_STRUCT
+#undef DYNARRAY_ELEMENT
+#undef DYNARRAY_PREFIX
+#undef DYNARRAY_ELEMENT_FREE
+#undef DYNARRAY_ELEMENT_INIT
+#undef DYNARRAY_INITIAL_SIZE
+#undef DYNARRAY_FINAL_TYPE
diff --git a/gl/lib/malloc/dynarray.h b/gl/lib/malloc/dynarray.h
new file mode 100644
index 0000000..a9a3b08
--- /dev/null
+++ b/gl/lib/malloc/dynarray.h
@@ -0,0 +1,177 @@
+/* Type-safe arrays which grow dynamically. Shared definitions.
+ Copyright (C) 2017-2023 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/>. */
+
+/* To use the dynarray facility, you need to include
+ <malloc/dynarray-skeleton.c> and define the parameter macros
+ documented in that file.
+
+ A minimal example which provides a growing list of integers can be
+ defined like this:
+
+ struct int_array
+ {
+ // Pointer to result array followed by its length,
+ // as required by DYNARRAY_FINAL_TYPE.
+ int *array;
+ size_t length;
+ };
+
+ #define DYNARRAY_STRUCT dynarray_int
+ #define DYNARRAY_ELEMENT int
+ #define DYNARRAY_PREFIX dynarray_int_
+ #define DYNARRAY_FINAL_TYPE struct int_array
+ #include <malloc/dynarray-skeleton.c>
+
+ To create a three-element array with elements 1, 2, 3, use this
+ code:
+
+ struct dynarray_int dyn;
+ dynarray_int_init (&dyn);
+ for (int i = 1; i <= 3; ++i)
+ {
+ int *place = dynarray_int_emplace (&dyn);
+ assert (place != NULL);
+ *place = i;
+ }
+ struct int_array result;
+ bool ok = dynarray_int_finalize (&dyn, &result);
+ assert (ok);
+ assert (result.length == 3);
+ assert (result.array[0] == 1);
+ assert (result.array[1] == 2);
+ assert (result.array[2] == 3);
+ free (result.array);
+
+ If the elements contain resources which must be freed, define
+ DYNARRAY_ELEMENT_FREE appropriately, like this:
+
+ struct str_array
+ {
+ char **array;
+ size_t length;
+ };
+
+ #define DYNARRAY_STRUCT dynarray_str
+ #define DYNARRAY_ELEMENT char *
+ #define DYNARRAY_ELEMENT_FREE(ptr) free (*ptr)
+ #define DYNARRAY_PREFIX dynarray_str_
+ #define DYNARRAY_FINAL_TYPE struct str_array
+ #include <malloc/dynarray-skeleton.c>
+
+ Compared to scratch buffers, dynamic arrays have the following
+ features:
+
+ - They have an element type, and are not just an untyped buffer of
+ bytes.
+
+ - When growing, previously stored elements are preserved. (It is
+ expected that scratch_buffer_grow_preserve and
+ scratch_buffer_set_array_size eventually go away because all
+ current users are moved to dynamic arrays.)
+
+ - Scratch buffers have a more aggressive growth policy because
+ growing them typically means a retry of an operation (across an
+ NSS service module boundary), which is expensive.
+
+ - For the same reason, scratch buffers have a much larger initial
+ stack allocation. */
+
+#ifndef _DYNARRAY_H
+#define _DYNARRAY_H
+
+#include <stddef.h>
+#include <string.h>
+
+struct dynarray_header
+{
+ size_t used;
+ size_t allocated;
+ void *array;
+};
+
+/* Marker used in the allocated member to indicate that an error was
+ encountered. */
+static inline size_t
+__dynarray_error_marker (void)
+{
+ return -1;
+}
+
+/* Internal function. See the has_failed function in
+ dynarray-skeleton.c. */
+static inline bool
+__dynarray_error (struct dynarray_header *list)
+{
+ return list->allocated == __dynarray_error_marker ();
+}
+
+/* Internal function. Enlarge the dynamically allocated area of the
+ array to make room for one more element. SCRATCH is a pointer to
+ the scratch area (which is not heap-allocated and must not be
+ freed). ELEMENT_SIZE is the size, in bytes, of one element.
+ Return false on failure, true on success. */
+bool __libc_dynarray_emplace_enlarge (struct dynarray_header *,
+ void *scratch, size_t element_size);
+
+/* Internal function. Enlarge the dynamically allocated area of the
+ array to make room for at least SIZE elements (which must be larger
+ than the existing used part of the dynamic array). SCRATCH is a
+ pointer to the scratch area (which is not heap-allocated and must
+ not be freed). ELEMENT_SIZE is the size, in bytes, of one element.
+ Return false on failure, true on success. */
+bool __libc_dynarray_resize (struct dynarray_header *, size_t size,
+ void *scratch, size_t element_size);
+
+/* Internal function. Like __libc_dynarray_resize, but clear the new
+ part of the dynamic array. */
+bool __libc_dynarray_resize_clear (struct dynarray_header *, size_t size,
+ void *scratch, size_t element_size);
+
+/* Internal type. */
+struct dynarray_finalize_result
+{
+ void *array;
+ size_t length;
+};
+
+/* Internal function. Copy the dynamically-allocated area to an
+ explicitly-sized heap allocation. SCRATCH is a pointer to the
+ embedded scratch space. ELEMENT_SIZE is the size, in bytes, of the
+ element type. On success, true is returned, and pointer and length
+ are written to *RESULT. On failure, false is returned. The caller
+ has to take care of some of the memory management; this function is
+ expected to be called from dynarray-skeleton.c. */
+bool __libc_dynarray_finalize (struct dynarray_header *list, void *scratch,
+ size_t element_size,
+ struct dynarray_finalize_result *result);
+
+
+/* Internal function. Terminate the process after an index error.
+ SIZE is the number of elements of the dynamic array. INDEX is the
+ lookup index which triggered the failure. */
+_Noreturn void __libc_dynarray_at_failure (size_t size, size_t index);
+
+#ifndef _ISOMAC
+libc_hidden_proto (__libc_dynarray_emplace_enlarge)
+libc_hidden_proto (__libc_dynarray_resize)
+libc_hidden_proto (__libc_dynarray_resize_clear)
+libc_hidden_proto (__libc_dynarray_finalize)
+libc_hidden_proto (__libc_dynarray_at_failure)
+#endif
+
+#endif /* _DYNARRAY_H */
diff --git a/gl/lib/malloc/dynarray_at_failure.c b/gl/lib/malloc/dynarray_at_failure.c
new file mode 100644
index 0000000..ebc9310
--- /dev/null
+++ b/gl/lib/malloc/dynarray_at_failure.c
@@ -0,0 +1,40 @@
+/* Report an dynamic array index out of bounds condition.
+ Copyright (C) 2017-2023 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/>. */
+
+#ifndef _LIBC
+# include <libc-config.h>
+# include <stdlib.h>
+#endif
+
+#include <dynarray.h>
+#include <stdio.h>
+
+void
+__libc_dynarray_at_failure (size_t size, size_t index)
+{
+#ifdef _LIBC
+ char buf[200];
+ __snprintf (buf, sizeof (buf), "Fatal glibc error: "
+ "array index %zu not less than array length %zu\n",
+ index, size);
+ __libc_fatal (buf);
+#else
+ abort ();
+#endif
+}
+libc_hidden_def (__libc_dynarray_at_failure)
diff --git a/gl/lib/malloc/dynarray_emplace_enlarge.c b/gl/lib/malloc/dynarray_emplace_enlarge.c
new file mode 100644
index 0000000..65aabb1
--- /dev/null
+++ b/gl/lib/malloc/dynarray_emplace_enlarge.c
@@ -0,0 +1,77 @@
+/* Increase the size of a dynamic array in preparation of an emplace operation.
+ Copyright (C) 2017-2023 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/>. */
+
+#ifndef _LIBC
+# include <libc-config.h>
+#endif
+
+#include <dynarray.h>
+#include <errno.h>
+#include <stdckdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+bool
+__libc_dynarray_emplace_enlarge (struct dynarray_header *list,
+ void *scratch, size_t element_size)
+{
+ size_t new_allocated;
+ if (list->allocated == 0)
+ {
+ /* No scratch buffer provided. Choose a reasonable default
+ size. */
+ if (element_size < 4)
+ new_allocated = 16;
+ else if (element_size < 8)
+ new_allocated = 8;
+ else
+ new_allocated = 4;
+ }
+ else
+ /* Increase the allocated size, using an exponential growth
+ policy. */
+ {
+ new_allocated = list->allocated + list->allocated / 2 + 1;
+ if (new_allocated <= list->allocated)
+ {
+ /* Overflow. */
+ __set_errno (ENOMEM);
+ return false;
+ }
+ }
+
+ size_t new_size;
+ if (ckd_mul (&new_size, new_allocated, element_size))
+ return false;
+ void *new_array;
+ if (list->array == scratch)
+ {
+ /* The previous array was not heap-allocated. */
+ new_array = malloc (new_size);
+ if (new_array != NULL && list->array != NULL)
+ memcpy (new_array, list->array, list->used * element_size);
+ }
+ else
+ new_array = realloc (list->array, new_size);
+ if (new_array == NULL)
+ return false;
+ list->array = new_array;
+ list->allocated = new_allocated;
+ return true;
+}
+libc_hidden_def (__libc_dynarray_emplace_enlarge)
diff --git a/gl/lib/malloc/dynarray_finalize.c b/gl/lib/malloc/dynarray_finalize.c
new file mode 100644
index 0000000..673595a
--- /dev/null
+++ b/gl/lib/malloc/dynarray_finalize.c
@@ -0,0 +1,66 @@
+/* Copy the dynamically-allocated area to an explicitly-sized heap allocation.
+ Copyright (C) 2017-2023 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/>. */
+
+#ifndef _LIBC
+# include <libc-config.h>
+#endif
+
+#include <dynarray.h>
+#include <stdlib.h>
+#include <string.h>
+
+bool
+__libc_dynarray_finalize (struct dynarray_header *list,
+ void *scratch, size_t element_size,
+ struct dynarray_finalize_result *result)
+{
+ if (__dynarray_error (list))
+ /* The caller will reported the deferred error. */
+ return false;
+
+ size_t used = list->used;
+
+ /* Empty list. */
+ if (used == 0)
+ {
+ /* An empty list could still be backed by a heap-allocated
+ array. Free it if necessary. */
+ if (list->array != scratch)
+ free (list->array);
+ *result = (struct dynarray_finalize_result) { NULL, 0 };
+ return true;
+ }
+
+ size_t allocation_size = used * element_size;
+ void *heap_array = malloc (allocation_size);
+ if (heap_array != NULL)
+ {
+ /* The new array takes ownership of the strings. */
+ if (list->array != NULL)
+ memcpy (heap_array, list->array, allocation_size);
+ if (list->array != scratch)
+ free (list->array);
+ *result = (struct dynarray_finalize_result)
+ { .array = heap_array, .length = used };
+ return true;
+ }
+ else
+ /* The caller will perform the freeing operation. */
+ return false;
+}
+libc_hidden_def (__libc_dynarray_finalize)
diff --git a/gl/lib/malloc/dynarray_resize.c b/gl/lib/malloc/dynarray_resize.c
new file mode 100644
index 0000000..014f98c
--- /dev/null
+++ b/gl/lib/malloc/dynarray_resize.c
@@ -0,0 +1,68 @@
+/* Increase the size of a dynamic array.
+ Copyright (C) 2017-2023 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/>. */
+
+#ifndef _LIBC
+# include <libc-config.h>
+#endif
+
+#include <dynarray.h>
+#include <errno.h>
+#include <stdckdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+bool
+__libc_dynarray_resize (struct dynarray_header *list, size_t size,
+ void *scratch, size_t element_size)
+{
+ /* The existing allocation provides sufficient room. */
+ if (size <= list->allocated)
+ {
+ list->used = size;
+ return true;
+ }
+
+ /* Otherwise, use size as the new allocation size. The caller is
+ expected to provide the final size of the array, so there is no
+ over-allocation here. */
+
+ size_t new_size_bytes;
+ if (ckd_mul (&new_size_bytes, size, element_size))
+ {
+ /* Overflow. */
+ __set_errno (ENOMEM);
+ return false;
+ }
+ void *new_array;
+ if (list->array == scratch)
+ {
+ /* The previous array was not heap-allocated. */
+ new_array = malloc (new_size_bytes);
+ if (new_array != NULL && list->array != NULL)
+ memcpy (new_array, list->array, list->used * element_size);
+ }
+ else
+ new_array = realloc (list->array, new_size_bytes);
+ if (new_array == NULL)
+ return false;
+ list->array = new_array;
+ list->allocated = size;
+ list->used = size;
+ return true;
+}
+libc_hidden_def (__libc_dynarray_resize)
diff --git a/gl/lib/malloc/dynarray_resize_clear.c b/gl/lib/malloc/dynarray_resize_clear.c
new file mode 100644
index 0000000..bb23c52
--- /dev/null
+++ b/gl/lib/malloc/dynarray_resize_clear.c
@@ -0,0 +1,39 @@
+/* Increase the size of a dynamic array and clear the new part.
+ Copyright (C) 2017-2023 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/>. */
+
+#ifndef _LIBC
+# include <libc-config.h>
+#endif
+
+#include <dynarray.h>
+#include <string.h>
+
+bool
+__libc_dynarray_resize_clear (struct dynarray_header *list, size_t size,
+ void *scratch, size_t element_size)
+{
+ size_t old_size = list->used;
+ if (!__libc_dynarray_resize (list, size, scratch, element_size))
+ return false;
+ /* __libc_dynarray_resize already checked for overflow. */
+ char *array = list->array;
+ memset (array + (old_size * element_size), 0,
+ (size - old_size) * element_size);
+ return true;
+}
+libc_hidden_def (__libc_dynarray_resize_clear)
diff --git a/gl/lib/malloc/scratch_buffer.h b/gl/lib/malloc/scratch_buffer.h
new file mode 100644
index 0000000..33fd2b2
--- /dev/null
+++ b/gl/lib/malloc/scratch_buffer.h
@@ -0,0 +1,135 @@
+/* Variable-sized buffer with on-stack default allocation.
+ Copyright (C) 2015-2023 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/>. */
+
+#ifndef _SCRATCH_BUFFER_H
+#define _SCRATCH_BUFFER_H
+
+/* Scratch buffers with a default stack allocation and fallback to
+ heap allocation. It is expected that this function is used in this
+ way:
+
+ struct scratch_buffer tmpbuf;
+ scratch_buffer_init (&tmpbuf);
+
+ while (!function_that_uses_buffer (tmpbuf.data, tmpbuf.length))
+ if (!scratch_buffer_grow (&tmpbuf))
+ return -1;
+
+ scratch_buffer_free (&tmpbuf);
+ return 0;
+
+ The allocation functions (scratch_buffer_grow,
+ scratch_buffer_grow_preserve, scratch_buffer_set_array_size) make
+ sure that the heap allocation, if any, is freed, so that the code
+ above does not have a memory leak. The buffer still remains in a
+ state that can be deallocated using scratch_buffer_free, so a loop
+ like this is valid as well:
+
+ struct scratch_buffer tmpbuf;
+ scratch_buffer_init (&tmpbuf);
+
+ while (!function_that_uses_buffer (tmpbuf.data, tmpbuf.length))
+ if (!scratch_buffer_grow (&tmpbuf))
+ break;
+
+ scratch_buffer_free (&tmpbuf);
+
+ scratch_buffer_grow and scratch_buffer_grow_preserve are guaranteed
+ to grow the buffer by at least 512 bytes. This means that when
+ using the scratch buffer as a backing store for a non-character
+ array whose element size, in bytes, is 512 or smaller, the scratch
+ buffer only has to grow once to make room for at least one more
+ element.
+*/
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdlib.h>
+
+/* Scratch buffer. Must be initialized with scratch_buffer_init
+ before its use. */
+struct scratch_buffer {
+ void *data; /* Pointer to the beginning of the scratch area. */
+ size_t length; /* Allocated space at the data pointer, in bytes. */
+ union { max_align_t __align; char __c[1024]; } __space;
+};
+
+/* Initializes *BUFFER so that BUFFER->data points to BUFFER->__space
+ and BUFFER->length reflects the available space. */
+static inline void
+scratch_buffer_init (struct scratch_buffer *buffer)
+{
+ buffer->data = buffer->__space.__c;
+ buffer->length = sizeof (buffer->__space);
+}
+
+/* Deallocates *BUFFER (if it was heap-allocated). */
+static inline void
+scratch_buffer_free (struct scratch_buffer *buffer)
+{
+ if (buffer->data != buffer->__space.__c)
+ free (buffer->data);
+}
+
+/* Grow *BUFFER by some arbitrary amount. The buffer contents is NOT
+ preserved. Return true on success, false on allocation failure (in
+ which case the old buffer is freed). On success, the new buffer is
+ larger than the previous size. On failure, *BUFFER is deallocated,
+ but remains in a free-able state, and errno is set. */
+bool __libc_scratch_buffer_grow (struct scratch_buffer *buffer);
+libc_hidden_proto (__libc_scratch_buffer_grow)
+
+/* Alias for __libc_scratch_buffer_grow. */
+static __always_inline bool
+scratch_buffer_grow (struct scratch_buffer *buffer)
+{
+ return __glibc_likely (__libc_scratch_buffer_grow (buffer));
+}
+
+/* Like __libc_scratch_buffer_grow, but preserve the old buffer
+ contents on success, as a prefix of the new buffer. */
+bool __libc_scratch_buffer_grow_preserve (struct scratch_buffer *buffer);
+libc_hidden_proto (__libc_scratch_buffer_grow_preserve)
+
+/* Alias for __libc_scratch_buffer_grow_preserve. */
+static __always_inline bool
+scratch_buffer_grow_preserve (struct scratch_buffer *buffer)
+{
+ return __glibc_likely (__libc_scratch_buffer_grow_preserve (buffer));
+}
+
+/* Grow *BUFFER so that it can store at least NELEM elements of SIZE
+ bytes. The buffer contents are NOT preserved. Both NELEM and SIZE
+ can be zero. Return true on success, false on allocation failure
+ (in which case the old buffer is freed, but *BUFFER remains in a
+ free-able state, and errno is set). It is unspecified whether this
+ function can reduce the array size. */
+bool __libc_scratch_buffer_set_array_size (struct scratch_buffer *buffer,
+ size_t nelem, size_t size);
+libc_hidden_proto (__libc_scratch_buffer_set_array_size)
+
+/* Alias for __libc_scratch_set_array_size. */
+static __always_inline bool
+scratch_buffer_set_array_size (struct scratch_buffer *buffer,
+ size_t nelem, size_t size)
+{
+ return __glibc_likely (__libc_scratch_buffer_set_array_size
+ (buffer, nelem, size));
+}
+
+#endif /* _SCRATCH_BUFFER_H */
diff --git a/gl/lib/malloc/scratch_buffer_grow.c b/gl/lib/malloc/scratch_buffer_grow.c
new file mode 100644
index 0000000..a5e8f2f
--- /dev/null
+++ b/gl/lib/malloc/scratch_buffer_grow.c
@@ -0,0 +1,56 @@
+/* Variable-sized buffer with on-stack default allocation.
+ Copyright (C) 2015-2023 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/>. */
+
+#ifndef _LIBC
+# include <libc-config.h>
+#endif
+
+#include <scratch_buffer.h>
+#include <errno.h>
+
+bool
+__libc_scratch_buffer_grow (struct scratch_buffer *buffer)
+{
+ void *new_ptr;
+ size_t new_length = buffer->length * 2;
+
+ /* Discard old buffer. */
+ scratch_buffer_free (buffer);
+
+ /* Check for overflow. */
+ if (__glibc_likely (new_length >= buffer->length))
+ new_ptr = malloc (new_length);
+ else
+ {
+ __set_errno (ENOMEM);
+ new_ptr = NULL;
+ }
+
+ if (__glibc_unlikely (new_ptr == NULL))
+ {
+ /* Buffer must remain valid to free. */
+ scratch_buffer_init (buffer);
+ return false;
+ }
+
+ /* Install new heap-based buffer. */
+ buffer->data = new_ptr;
+ buffer->length = new_length;
+ return true;
+}
+libc_hidden_def (__libc_scratch_buffer_grow)
diff --git a/gl/lib/malloc/scratch_buffer_grow_preserve.c b/gl/lib/malloc/scratch_buffer_grow_preserve.c
new file mode 100644
index 0000000..c0b5d87
--- /dev/null
+++ b/gl/lib/malloc/scratch_buffer_grow_preserve.c
@@ -0,0 +1,67 @@
+/* Variable-sized buffer with on-stack default allocation.
+ Copyright (C) 2015-2023 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/>. */
+
+#ifndef _LIBC
+# include <libc-config.h>
+#endif
+
+#include <scratch_buffer.h>
+#include <errno.h>
+#include <string.h>
+
+bool
+__libc_scratch_buffer_grow_preserve (struct scratch_buffer *buffer)
+{
+ size_t new_length = 2 * buffer->length;
+ void *new_ptr;
+
+ if (buffer->data == buffer->__space.__c)
+ {
+ /* Move buffer to the heap. No overflow is possible because
+ buffer->length describes a small buffer on the stack. */
+ new_ptr = malloc (new_length);
+ if (new_ptr == NULL)
+ return false;
+ memcpy (new_ptr, buffer->__space.__c, buffer->length);
+ }
+ else
+ {
+ /* Buffer was already on the heap. Check for overflow. */
+ if (__glibc_likely (new_length >= buffer->length))
+ new_ptr = realloc (buffer->data, new_length);
+ else
+ {
+ __set_errno (ENOMEM);
+ new_ptr = NULL;
+ }
+
+ if (__glibc_unlikely (new_ptr == NULL))
+ {
+ /* Deallocate, but buffer must remain valid to free. */
+ free (buffer->data);
+ scratch_buffer_init (buffer);
+ return false;
+ }
+ }
+
+ /* Install new heap-based buffer. */
+ buffer->data = new_ptr;
+ buffer->length = new_length;
+ return true;
+}
+libc_hidden_def (__libc_scratch_buffer_grow_preserve)
diff --git a/gl/lib/malloc/scratch_buffer_set_array_size.c b/gl/lib/malloc/scratch_buffer_set_array_size.c
new file mode 100644
index 0000000..24c3935
--- /dev/null
+++ b/gl/lib/malloc/scratch_buffer_set_array_size.c
@@ -0,0 +1,64 @@
+/* Variable-sized buffer with on-stack default allocation.
+ Copyright (C) 2015-2023 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/>. */
+
+#ifndef _LIBC
+# include <libc-config.h>
+#endif
+
+#include <scratch_buffer.h>
+#include <errno.h>
+#include <limits.h>
+
+bool
+__libc_scratch_buffer_set_array_size (struct scratch_buffer *buffer,
+ size_t nelem, size_t size)
+{
+ size_t new_length = nelem * size;
+
+ /* Avoid overflow check if both values are small. */
+ if ((nelem | size) >> (sizeof (size_t) * CHAR_BIT / 2) != 0
+ && nelem != 0 && size != new_length / nelem)
+ {
+ /* Overflow. Discard the old buffer, but it must remain valid
+ to free. */
+ scratch_buffer_free (buffer);
+ scratch_buffer_init (buffer);
+ __set_errno (ENOMEM);
+ return false;
+ }
+
+ if (new_length <= buffer->length)
+ return true;
+
+ /* Discard old buffer. */
+ scratch_buffer_free (buffer);
+
+ char *new_ptr = malloc (new_length);
+ if (new_ptr == NULL)
+ {
+ /* Buffer must remain valid to free. */
+ scratch_buffer_init (buffer);
+ return false;
+ }
+
+ /* Install new heap-based buffer. */
+ buffer->data = new_ptr;
+ buffer->length = new_length;
+ return true;
+}
+libc_hidden_def (__libc_scratch_buffer_set_array_size)