/* Set data type implemented by an array. Copyright (C) 2006-2023 Free Software Foundation, Inc. Written by Bruno Haible , 2018. 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 . */ #include /* Specification. */ #include "gl_array_set.h" #include #include /* Checked size_t computations. */ #include "xsize.h" /* --------------------------- gl_set_t Data Type --------------------------- */ /* Concrete gl_set_impl type, valid for this file only. */ struct gl_set_impl { struct gl_set_impl_base base; /* An array of ALLOCATED elements, of which the first COUNT are used. 0 <= COUNT <= ALLOCATED. */ const void **elements; size_t count; size_t allocated; }; static gl_set_t gl_array_nx_create_empty (gl_set_implementation_t implementation, gl_setelement_equals_fn equals_fn, gl_setelement_hashcode_fn hashcode_fn, gl_setelement_dispose_fn dispose_fn) { struct gl_set_impl *set = (struct gl_set_impl *) malloc (sizeof (struct gl_set_impl)); if (set == NULL) return NULL; set->base.vtable = implementation; set->base.equals_fn = equals_fn; set->base.dispose_fn = dispose_fn; set->elements = NULL; set->count = 0; set->allocated = 0; return set; } static size_t gl_array_size (gl_set_t set) { return set->count; } static bool gl_array_search (gl_set_t set, const void *elt) { size_t count = set->count; if (count > 0) { gl_setelement_equals_fn equals = set->base.equals_fn; const void **elements = set->elements; if (equals != NULL) { size_t i; for (i = 0; i < count; i++) if (equals (elements[i], elt)) return true; } else { size_t i; for (i = 0; i < count; i++) if (elements[i] == elt) return true; } } return false; } /* Ensure that set->allocated > set->count. Return 0 upon success, -1 upon out-of-memory. */ static int grow (gl_set_t set) { size_t new_allocated; size_t memory_size; const void **memory; new_allocated = xtimes (set->allocated, 2); new_allocated = xsum (new_allocated, 1); memory_size = xtimes (new_allocated, sizeof (const void *)); if (size_overflow_p (memory_size)) /* Overflow, would lead to out of memory. */ return -1; memory = (const void **) realloc (set->elements, memory_size); if (memory == NULL) /* Out of memory. */ return -1; set->elements = memory; set->allocated = new_allocated; return 0; } static int gl_array_nx_add (gl_set_t set, const void *elt) { if (gl_array_search (set, elt)) return 0; else { size_t count = set->count; if (count == set->allocated) if (grow (set) < 0) return -1; set->elements[count] = elt; set->count = count + 1; return 1; } } /* Remove the element at the given position, 0 <= position < gl_set_size (set). */ static void gl_array_remove_at (gl_set_t set, size_t position) { size_t count = set->count; const void **elements = set->elements; size_t i; if (set->base.dispose_fn != NULL) set->base.dispose_fn (elements[position]); for (i = position + 1; i < count; i++) elements[i - 1] = elements[i]; set->count = count - 1; } static bool gl_array_remove (gl_set_t set, const void *elt) { size_t count = set->count; if (count > 0) { gl_setelement_equals_fn equals = set->base.equals_fn; const void **elements = set->elements; if (equals != NULL) { size_t i; for (i = 0; i < count; i++) if (equals (elements[i], elt)) { gl_array_remove_at (set, i); return true; } } else { size_t i; for (i = 0; i < count; i++) if (elements[i] == elt) { gl_array_remove_at (set, i); return true; } } } return false; } static void gl_array_free (gl_set_t set) { if (set->elements != NULL) { if (set->base.dispose_fn != NULL) { size_t count = set->count; if (count > 0) { gl_setelement_dispose_fn dispose = set->base.dispose_fn; const void **elements = set->elements; do dispose (*elements++); while (--count > 0); } } free (set->elements); } free (set); } /* ---------------------- gl_set_iterator_t Data Type ---------------------- */ static gl_set_iterator_t gl_array_iterator (gl_set_t set) { gl_set_iterator_t result; result.vtable = set->base.vtable; result.set = set; result.count = set->count; result.p = set->elements + 0; result.q = set->elements + set->count; #if defined GCC_LINT || defined lint result.i = 0; result.j = 0; #endif return result; } static bool gl_array_iterator_next (gl_set_iterator_t *iterator, const void **eltp) { gl_set_t set = iterator->set; if (iterator->count != set->count) { if (iterator->count != set->count + 1) /* Concurrent modifications were done on the set. */ abort (); /* The last returned element was removed. */ iterator->count--; iterator->p = (const void **) iterator->p - 1; iterator->q = (const void **) iterator->q - 1; } if (iterator->p < iterator->q) { const void **p = (const void **) iterator->p; *eltp = *p; iterator->p = p + 1; return true; } else return false; } static void gl_array_iterator_free (gl_set_iterator_t *iterator) { } const struct gl_set_implementation gl_array_set_implementation = { gl_array_nx_create_empty, gl_array_size, gl_array_search, gl_array_nx_add, gl_array_remove, gl_array_free, gl_array_iterator, gl_array_iterator_next, gl_array_iterator_free };