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-rw-r--r--array.c130
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+/*
+ chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar 2014
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * 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, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ **********************************************************************
+
+ =======================================================================
+
+ Functions implementing an array with automatic memory allocation.
+
+ */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include "array.h"
+#include "memory.h"
+
+struct ARR_Instance_Record {
+ void *data;
+ unsigned int elem_size;
+ unsigned int used;
+ unsigned int allocated;
+};
+
+ARR_Instance
+ARR_CreateInstance(unsigned int elem_size)
+{
+ ARR_Instance array;
+
+ assert(elem_size > 0);
+
+ array = MallocNew(struct ARR_Instance_Record);
+
+ array->data = NULL;
+ array->elem_size = elem_size;
+ array->used = 0;
+ array->allocated = 0;
+
+ return array;
+}
+
+void
+ARR_DestroyInstance(ARR_Instance array)
+{
+ Free(array->data);
+ Free(array);
+}
+
+static void
+realloc_array(ARR_Instance array, unsigned int min_size)
+{
+ assert(min_size <= 2 * min_size);
+ if (array->allocated >= min_size && array->allocated <= 2 * min_size)
+ return;
+
+ if (array->allocated < min_size) {
+ while (array->allocated < min_size)
+ array->allocated = array->allocated ? 2 * array->allocated : 1;
+ } else {
+ array->allocated = min_size;
+ }
+
+ array->data = Realloc2(array->data, array->allocated, array->elem_size);
+}
+
+void *
+ARR_GetNewElement(ARR_Instance array)
+{
+ array->used++;
+ realloc_array(array, array->used);
+ return ARR_GetElement(array, array->used - 1);
+}
+
+void *
+ARR_GetElement(ARR_Instance array, unsigned int index)
+{
+ assert(index < array->used);
+ return (void *)((char *)array->data + (size_t)index * array->elem_size);
+}
+
+void *
+ARR_GetElements(ARR_Instance array)
+{
+ /* Return a non-NULL pointer when the array has zero size */
+ if (!array->data) {
+ assert(!array->used);
+ return array;
+ }
+
+ return array->data;
+}
+
+void
+ARR_AppendElement(ARR_Instance array, void *element)
+{
+ void *e;
+
+ e = ARR_GetNewElement(array);
+ memcpy(e, element, array->elem_size);
+}
+
+void
+ARR_SetSize(ARR_Instance array, unsigned int size)
+{
+ realloc_array(array, size);
+ array->used = size;
+}
+
+unsigned int
+ARR_GetSize(ARR_Instance array)
+{
+ return array->used;
+}