1 /* a generic DYNamic ARray implementation. */
3 /* Copyright (c) 2004-2021. The SimGrid Team.
4 * All rights reserved. */
6 /* This program is free software; you can redistribute it and/or modify it
7 * under the terms of the license (GNU LGPL) which comes with this package. */
10 #include "simgrid/Exception.hpp"
14 #include "xbt/string.hpp"
15 #include "xbt/sysdep.h"
16 #include <sys/types.h>
18 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_dyn, xbt, "Dynamic arrays");
20 static inline void _sanity_check_dynar(const_xbt_dynar_t dynar)
22 xbt_assert(dynar, "dynar is nullptr");
25 static inline void _sanity_check_idx(int idx)
27 xbt_assert(idx >= 0, "dynar idx(=%d) < 0", idx);
30 static inline void _check_inbound_idx(const_xbt_dynar_t dynar, int idx)
32 xbt_assert(idx >= 0 && idx < static_cast<int>(dynar->used),
33 "dynar is not that long. You asked %d, but it's only %lu long", idx, dynar->used);
36 static inline void _check_populated_dynar(const_xbt_dynar_t dynar)
38 xbt_assert(dynar->used > 0, "dynar %p is empty", dynar);
41 static inline void _xbt_dynar_resize(xbt_dynar_t dynar, unsigned long new_size)
43 if (new_size != dynar->size) {
44 dynar->size = new_size;
45 dynar->data = xbt_realloc(dynar->data, new_size * dynar->elmsize);
49 static inline void _xbt_dynar_expand(xbt_dynar_t dynar, unsigned long nb)
51 const unsigned long old_size = dynar->size;
54 const unsigned long expand = 2 * (old_size + 1);
55 _xbt_dynar_resize(dynar, (nb > expand ? nb : expand));
56 XBT_DEBUG("expand %p from %lu to %lu elements", dynar, old_size, dynar->size);
60 static inline void* _xbt_dynar_elm(const_xbt_dynar_t dynar, unsigned long idx)
62 auto* const data = static_cast<char*>(dynar->data);
63 const unsigned long elmsize = dynar->elmsize;
65 return data + idx * elmsize;
68 static inline void _xbt_dynar_get_elm(void* dst, const_xbt_dynar_t dynar, unsigned long idx)
70 const void* const elm = _xbt_dynar_elm(dynar, idx);
71 memcpy(dst, elm, dynar->elmsize);
74 /** @brief Constructor
76 * @param elmsize size of each element in the dynar
77 * @param free_f function to call each time we want to get rid of an element (or nullptr if nothing to do).
79 * Creates a new dynar. If a free_func is provided, the elements have to be pointer of pointer. That is to say that
80 * dynars can contain either base types (int, char, double, etc) or pointer of pointers (struct **).
82 xbt_dynar_t xbt_dynar_new(const unsigned long elmsize, void_f_pvoid_t free_f)
84 xbt_dynar_t dynar = xbt_new0(s_xbt_dynar_t, 1);
88 dynar->elmsize = elmsize;
89 dynar->data = nullptr;
90 dynar->free_f = free_f;
95 /** @brief Destructor of the structure not touching to the content
97 * @param dynar poor victim
99 * kilkil a dynar BUT NOT its content. Ie, the array is freed, but the content is not touched (the @a free_f function
102 void xbt_dynar_free_container(xbt_dynar_t* dynar)
104 if (dynar && *dynar) {
105 xbt_dynar_t d = *dynar;
112 /** @brief Frees the content and set the size to 0
114 * @param dynar who to squeeze
116 void xbt_dynar_reset(xbt_dynar_t dynar)
118 _sanity_check_dynar(dynar);
120 XBT_CDEBUG(xbt_dyn, "Reset the dynar %p", (void *) dynar);
122 xbt_dynar_map(dynar, dynar->free_f);
128 * @brief Shrink the dynar by removing empty slots at the end of the internal array
129 * @param dynar a dynar
130 * @param empty_slots_wanted number of empty slots you want to keep at the end of the internal array for further
133 * Reduces the internal array size of the dynar to the number of elements plus @a empty_slots_wanted.
134 * After removing elements from the dynar, you can call this function to make the dynar use less memory.
135 * Set @a empty_slots_wanted to zero to reduce the dynar internal array as much as possible.
136 * Note that if @a empty_slots_wanted is greater than the array size, the internal array is expanded instead of shrunk.
138 void xbt_dynar_shrink(xbt_dynar_t dynar, int empty_slots_wanted)
140 _xbt_dynar_resize(dynar, dynar->used + empty_slots_wanted);
143 /** @brief Destructor
145 * @param dynar poor victim
147 * kilkil a dynar and its content
149 void xbt_dynar_free(xbt_dynar_t* dynar)
151 if (dynar && *dynar) {
152 xbt_dynar_reset(*dynar);
153 xbt_dynar_free_container(dynar);
157 /** @brief Count of dynar's elements
159 * @param dynar the dynar we want to measure
161 unsigned long xbt_dynar_length(const_xbt_dynar_t dynar)
163 return (dynar ? dynar->used : 0UL);
166 /**@brief check if a dynar is empty
168 *@param dynar the dynat we want to check
170 int xbt_dynar_is_empty(const_xbt_dynar_t dynar)
172 return (xbt_dynar_length(dynar) == 0);
175 /** @brief Retrieve a copy of the Nth element of a dynar.
177 * @param dynar information dealer
178 * @param idx index of the slot we want to retrieve
179 * @param[out] dst where to put the result to.
181 void xbt_dynar_get_cpy(const_xbt_dynar_t dynar, unsigned long idx, void* dst)
183 _sanity_check_dynar(dynar);
184 _check_inbound_idx(dynar, idx);
186 _xbt_dynar_get_elm(dst, dynar, idx);
189 /** @brief Retrieve a pointer to the Nth element of a dynar.
191 * @param dynar information dealer
192 * @param idx index of the slot we want to retrieve
193 * @return the @a idx-th element of @a dynar.
195 * @warning The returned value is the actual content of the dynar.
196 * Make a copy before fooling with it.
198 void* xbt_dynar_get_ptr(const_xbt_dynar_t dynar, unsigned long idx)
201 _sanity_check_dynar(dynar);
202 _check_inbound_idx(dynar, idx);
204 res = _xbt_dynar_elm(dynar, idx);
208 void* xbt_dynar_set_at_ptr(const xbt_dynar_t dynar, unsigned long idx)
210 _sanity_check_dynar(dynar);
212 if (idx >= dynar->used) {
213 _xbt_dynar_expand(dynar, idx + 1);
214 if (idx > dynar->used) {
215 memset(_xbt_dynar_elm(dynar, dynar->used), 0, (idx - dynar->used) * dynar->elmsize);
217 dynar->used = idx + 1;
219 return _xbt_dynar_elm(dynar, idx);
222 /** @brief Make room for a new element, and return a pointer to it
224 * You can then use regular affectation to set its value instead of relying on the slow memcpy. This is what
225 * xbt_dynar_insert_at_as() does.
227 void* xbt_dynar_insert_at_ptr(xbt_dynar_t dynar, int idx)
230 unsigned long old_used;
231 unsigned long new_used;
234 _sanity_check_dynar(dynar);
235 _sanity_check_idx(idx);
237 old_used = dynar->used;
238 new_used = old_used + 1;
240 _xbt_dynar_expand(dynar, new_used);
242 nb_shift = old_used - idx;
245 memmove(_xbt_dynar_elm(dynar, idx + 1), _xbt_dynar_elm(dynar, idx), nb_shift * dynar->elmsize);
248 dynar->used = new_used;
249 res = _xbt_dynar_elm(dynar, idx);
253 /** @brief Set the Nth dynar's element, expanding the dynar and sliding the previous values to the right
255 * Set the Nth element of a dynar, expanding the dynar if needed, and moving the previously existing value and all
256 * subsequent ones to one position right in the dynar.
258 void xbt_dynar_insert_at(xbt_dynar_t dynar, int idx, const void* src)
260 /* checks done in xbt_dynar_insert_at_ptr */
261 memcpy(xbt_dynar_insert_at_ptr(dynar, idx), src, dynar->elmsize);
264 /** @brief Remove the Nth dynar's element, sliding the previous values to the left
266 * Get the Nth element of a dynar, removing it from the dynar and moving all subsequent values to one position left in
269 * If the object argument of this function is a non-null pointer, the removed element is copied to this address. If not,
270 * the element is freed using the free_f function passed at dynar creation.
272 void xbt_dynar_remove_at(xbt_dynar_t dynar, int idx, void* object)
274 _sanity_check_dynar(dynar);
275 _check_inbound_idx(dynar, idx);
278 _xbt_dynar_get_elm(object, dynar, idx);
279 } else if (dynar->free_f) {
280 dynar->free_f(_xbt_dynar_elm(dynar, idx));
283 unsigned long nb_shift = dynar->used - 1 - idx;
286 unsigned long offset = nb_shift * dynar->elmsize;
287 memmove(_xbt_dynar_elm(dynar, idx), _xbt_dynar_elm(dynar, idx + 1), offset);
293 /** @brief Returns a boolean indicating whether the element is part of the dynar
295 * Beware that if your dynar contains pointed values (such as strings) instead of scalar, this function is probably not
298 int xbt_dynar_member(const_xbt_dynar_t dynar, const void* elem)
300 for (unsigned long it = 0; it < dynar->used; it++)
301 if (not memcmp(_xbt_dynar_elm(dynar, it), elem, dynar->elmsize)) {
308 /** @brief Make room at the end of the dynar for a new element, and return a pointer to it.
310 * You can then use regular affectation to set its value instead of relying on the slow memcpy. This is what
311 * xbt_dynar_push_as() does.
313 void* xbt_dynar_push_ptr(xbt_dynar_t dynar)
315 return xbt_dynar_insert_at_ptr(dynar, dynar->used);
318 /** @brief Add an element at the end of the dynar */
319 void xbt_dynar_push(xbt_dynar_t dynar, const void* src)
321 /* checks done in xbt_dynar_insert_at_ptr */
322 memcpy(xbt_dynar_insert_at_ptr(dynar, dynar->used), src, dynar->elmsize);
325 /** @brief Mark the last dynar's element as unused and return a pointer to it.
327 * You can then use regular affectation to set its value instead of relying on the slow memcpy. This is what
328 * xbt_dynar_pop_as() does.
330 void* xbt_dynar_pop_ptr(xbt_dynar_t dynar)
332 _check_populated_dynar(dynar);
333 XBT_CDEBUG(xbt_dyn, "Pop %p", (void *) dynar);
335 return _xbt_dynar_elm(dynar, dynar->used);
338 /** @brief Get and remove the last element of the dynar */
339 void xbt_dynar_pop(xbt_dynar_t dynar, void* dst)
341 /* sanity checks done by remove_at */
342 XBT_CDEBUG(xbt_dyn, "Pop %p", (void *) dynar);
343 xbt_dynar_remove_at(dynar, dynar->used - 1, dst);
346 /** @brief Add an element at the beginning of the dynar.
348 * This is less efficient than xbt_dynar_push()
350 void xbt_dynar_unshift(xbt_dynar_t dynar, const void* src)
352 /* sanity checks done by insert_at */
353 xbt_dynar_insert_at(dynar, 0, src);
356 /** @brief Get and remove the first element of the dynar.
358 * This is less efficient than xbt_dynar_pop()
360 void xbt_dynar_shift(xbt_dynar_t dynar, void* dst)
362 /* sanity checks done by remove_at */
363 xbt_dynar_remove_at(dynar, 0, dst);
366 /** @brief Apply a function to each member of a dynar
368 * The mapped function may change the value of the element itself, but should not mess with the structure of the dynar.
370 void xbt_dynar_map(const_xbt_dynar_t dynar, void_f_pvoid_t op)
372 auto* const data = static_cast<char*>(dynar->data);
373 const unsigned long elmsize = dynar->elmsize;
374 const unsigned long used = dynar->used;
376 _sanity_check_dynar(dynar);
378 for (unsigned long i = 0; i < used; i++) {
379 char* elm = data + i * elmsize;
384 /** @brief Sorts a dynar according to the function <tt>compar_fn</tt>
386 * This function simply apply the classical qsort(3) function to the data stored in the dynar.
387 * You should thus refer to the libc documentation, or to some online tutorial on how to write
388 * a comparison function. Here is a quick example if you have integers in your dynar:
391 * int cmpfunc (const void * a, const void * b) {
392 * int intA = *(int*)a;
393 * int intB = *(int*)b;
394 * return intA - intB;
398 * and now to sort a dynar of MSG hosts depending on their speed:
400 * int cmpfunc(const MSG_host_t a, const MSG_host_t b) {
401 * MSG_host_t hostA = *(MSG_host_t*)a;
402 * MSG_host_t hostB = *(MSG_host_t*)b;
403 * return MSG_host_get_speed(hostA) - MSG_host_get_speed(hostB);
407 * @param dynar the dynar to sort
408 * @param compar_fn comparison function of type (int (compar_fn*) (const void*) (const void*)).
410 void xbt_dynar_sort(const_xbt_dynar_t dynar, int_f_cpvoid_cpvoid_t compar_fn)
412 if (dynar->data != nullptr)
413 qsort(dynar->data, dynar->used, dynar->elmsize, compar_fn);
416 /** @brief Transform a dynar into a nullptr terminated array.
418 * @param dynar the dynar to transform
419 * @return pointer to the first element of the array
421 * Note: The dynar won't be usable afterwards.
423 void* xbt_dynar_to_array(xbt_dynar_t dynar)
426 xbt_dynar_shrink(dynar, 1);
427 memset(xbt_dynar_push_ptr(dynar), 0, dynar->elmsize);