xref: /lighttpd1.4/src/array.c (revision 4f0261e5)
1 #include "first.h"
2 
3 #include "array.h"
4 #include "buffer.h"
5 
6 #include <string.h>
7 #include <stdlib.h>
8 #include <limits.h>
9 
10 #include <errno.h>
11 #include <assert.h>
12 
13 #define ARRAY_NOT_FOUND ((size_t)(-1))
14 
15 array *array_init(void) {
16 	array *a;
17 
18 	a = calloc(1, sizeof(*a));
19 	force_assert(a);
20 
21 	return a;
22 }
23 
24 array *array_init_array(array *src) {
25 	size_t i;
26 	array *a = array_init();
27 
28 	if (0 == src->size) return a;
29 
30 	a->used = src->used;
31 	a->size = src->size;
32 	a->unique_ndx = src->unique_ndx;
33 
34 	a->data = malloc(sizeof(*src->data) * src->size);
35 	force_assert(NULL != a->data);
36 	for (i = 0; i < src->size; i++) {
37 		if (src->data[i]) a->data[i] = src->data[i]->fn->copy(src->data[i]);
38 		else a->data[i] = NULL;
39 	}
40 
41 	a->sorted = malloc(sizeof(*src->sorted) * src->size);
42 	force_assert(NULL != a->sorted);
43 	memcpy(a->sorted, src->sorted, sizeof(*src->sorted) * src->size);
44 	return a;
45 }
46 
47 void array_free(array *a) {
48 	size_t i;
49 	if (!a) return;
50 
51 	for (i = 0; i < a->size; i++) {
52 		if (a->data[i]) a->data[i]->fn->free(a->data[i]);
53 	}
54 
55 	if (a->data) free(a->data);
56 	if (a->sorted) free(a->sorted);
57 
58 	free(a);
59 }
60 
61 void array_reset(array *a) {
62 	size_t i;
63 	if (!a) return;
64 
65 	for (i = 0; i < a->used; i++) {
66 		a->data[i]->fn->reset(a->data[i]);
67 		a->data[i]->is_index_key = 0;
68 	}
69 
70 	a->used = 0;
71 	a->unique_ndx = 0;
72 }
73 
74 void array_reset_data_strings(array *a) {
75 	if (!a) return;
76 
77 	for (size_t i = 0; i < a->used; ++i) {
78 		data_string * const ds = (data_string *)a->data[i];
79 		/*force_assert(ds->type == TYPE_STRING);*/
80 		ds->is_index_key = 0;
81 		buffer_reset(ds->key);
82 		buffer_reset(ds->value);
83 	}
84 
85 	a->used = 0;
86 	a->unique_ndx = 0;
87 }
88 
89 data_unset *array_pop(array *a) {
90 	data_unset *du;
91 
92 	force_assert(a->used != 0);
93 
94 	a->used --;
95 	du = a->data[a->used];
96 	force_assert(a->sorted[a->used] == a->used); /* only works on "simple" lists */
97 	a->data[a->used] = NULL;
98 
99 	return du;
100 }
101 
102 static int array_keycmp(const char *a, size_t alen, const char *b, size_t blen) {
103     return alen < blen ? -1 : alen > blen ? 1 : buffer_caseless_compare(a, alen, b, blen);
104 }
105 
106 /* returns index of element or ARRAY_NOT_FOUND
107  * if rndx != NULL it stores the position in a->sorted[] where the key needs
108  * to be inserted
109  */
110 static size_t array_get_index(const array *a, const char *key, size_t keylen, size_t *rndx) {
111 	/* invariant: [lower-1] < key < [upper]
112 	 * "virtual elements": [-1] = -INFTY, [a->used] = +INFTY
113 	 * also an invariant: 0 <= lower <= upper <= a->used
114 	 */
115 	size_t lower = 0, upper = a->used;
116 	force_assert(upper <= SSIZE_MAX); /* (lower + upper) can't overflow */
117 
118 	while (lower != upper) {
119 		size_t probe = (lower + upper) / 2;
120 		const buffer *b = a->data[a->sorted[probe]]->key;
121 		int cmp = array_keycmp(key, keylen, CONST_BUF_LEN(b));
122 
123 		if (cmp == 0) {
124 			/* found */
125 			if (rndx) *rndx = probe;
126 			return a->sorted[probe];
127 		} else if (cmp < 0) {
128 			/* key < [probe] */
129 			upper = probe; /* still: lower <= upper */
130 		} else {
131 			/* key > [probe] */
132 			lower = probe + 1; /* still: lower <= upper */
133 		}
134 	}
135 
136 	/* not found: [lower-1] < key < [upper] = [lower] ==> insert at [lower] */
137 	if (rndx) *rndx = lower;
138 	return ARRAY_NOT_FOUND;
139 }
140 
141 data_unset *array_get_element_klen(const array *a, const char *key, size_t klen) {
142 	size_t ndx;
143 	force_assert(NULL != key);
144 
145 	if (ARRAY_NOT_FOUND != (ndx = array_get_index(a, key, klen, NULL))) {
146 		/* found, return it */
147 		return a->data[ndx];
148 	}
149 
150 	return NULL;
151 }
152 
153 data_unset *array_extract_element_klen(array *a, const char *key, size_t klen) {
154 	size_t ndx, pos;
155 	force_assert(NULL != key);
156 
157 	if (ARRAY_NOT_FOUND != (ndx = array_get_index(a, key, klen, &pos))) {
158 		/* found */
159 		const size_t last_ndx = a->used - 1;
160 		data_unset *entry = a->data[ndx];
161 
162 		/* now we need to swap it with the last element (if it isn't already the last element) */
163 		if (ndx != last_ndx) {
164 			/* to swap we also need to modify the index in a->sorted - find pos of last_elem there */
165 			size_t last_elem_pos;
166 			/* last element must be present at the expected position */
167 			force_assert(last_ndx == array_get_index(a, CONST_BUF_LEN(a->data[last_ndx]->key), &last_elem_pos));
168 
169 			/* move entry from last_ndx to ndx */
170 			a->data[ndx] = a->data[last_ndx];
171 			a->data[last_ndx] = NULL;
172 
173 			/* fix index entry for moved entry */
174 			a->sorted[last_elem_pos] = ndx;
175 		} else {
176 			a->data[ndx] = NULL;
177 		}
178 
179 		/* remove entry in a->sorted: move everything after pos one step to the left */
180 		if (pos != last_ndx) {
181 			memmove(a->sorted + pos, a->sorted + pos + 1, (last_ndx - pos) * sizeof(*a->sorted));
182 		}
183 		a->sorted[last_ndx] = ARRAY_NOT_FOUND;
184 		--a->used;
185 
186 		return entry;
187 	}
188 
189 	return NULL;
190 }
191 
192 static data_unset *array_get_unused_element(array *a, data_type_t t) {
193 	data_unset *ds = NULL;
194 	unsigned int i;
195 
196 	for (i = a->used; i < a->size; i++) {
197 		if (a->data[i] && a->data[i]->type == t) {
198 			ds = a->data[i];
199 
200 			/* make empty slot at a->used for next insert */
201 			a->data[i] = a->data[a->used];
202 			a->data[a->used] = NULL;
203 
204 			return ds;
205 		}
206 	}
207 
208 	return NULL;
209 }
210 
211 void array_set_key_value(array *hdrs, const char *key, size_t key_len, const char *value, size_t val_len) {
212 	data_string *ds;
213 
214 	if (NULL != (ds = (data_string *)array_get_element_klen(hdrs, key, key_len))) {
215 		buffer_copy_string_len(ds->value, value, val_len);
216 		return;
217 	}
218 
219 	array_insert_key_value(hdrs, key, key_len, value, val_len);
220 }
221 
222 void array_insert_key_value(array *hdrs, const char *key, size_t key_len, const char *value, size_t val_len) {
223 	data_string *ds;
224 
225 	if (NULL == (ds = (data_string *)array_get_unused_element(hdrs, TYPE_STRING))) {
226 		ds = data_string_init();
227 	}
228 
229 	buffer_copy_string_len(ds->key, key, key_len);
230 	buffer_copy_string_len(ds->value, value, val_len);
231 	array_insert_unique(hdrs, (data_unset *)ds);
232 }
233 
234 void array_insert_value(array *hdrs, const char *value, size_t val_len) {
235 	data_string *ds;
236 
237 	if (NULL == (ds = (data_string *)array_get_unused_element(hdrs, TYPE_STRING))) {
238 		ds = data_string_init();
239 	}
240 
241 	buffer_copy_string_len(ds->value, value, val_len);
242 	array_insert_unique(hdrs, (data_unset *)ds);
243 }
244 
245 int * array_get_int_ptr(array *a, const char *k, size_t klen) {
246 	data_integer *di = (data_integer *)array_get_element_klen(a, k, klen);
247 
248 	if (NULL == di) {
249 		di = (data_integer *)array_get_unused_element(a, TYPE_INTEGER);
250 		if (NULL == di) di = data_integer_init();
251 		buffer_copy_string_len(di->key, k, klen);
252 		array_insert_unique(a, (data_unset *)di);
253 	}
254 
255 	return &di->value;
256 }
257 
258 /* if entry already exists return pointer to existing entry, otherwise insert entry and return NULL */
259 static data_unset **array_find_or_insert(array *a, data_unset *entry) {
260 	size_t ndx, pos, j;
261 
262 	/* generate unique index if neccesary */
263 	if (buffer_is_empty(entry->key) || entry->is_index_key) {
264 		buffer_copy_int(entry->key, a->unique_ndx++);
265 		entry->is_index_key = 1;
266 		force_assert(0 != a->unique_ndx); /* must not wrap or we'll get problems */
267 	}
268 
269 	/* try to find the entry */
270 	if (ARRAY_NOT_FOUND != (ndx = array_get_index(a, CONST_BUF_LEN(entry->key), &pos))) {
271 		/* found collision, return it */
272 		return &a->data[ndx];
273 	}
274 
275 	/* insert */
276 
277 	/* there couldn't possibly be enough memory to store so many entries */
278 	force_assert(a->used + 1 <= SSIZE_MAX);
279 
280 	if (a->size == a->used) {
281 		a->size  += 16;
282 		a->data   = realloc(a->data,   sizeof(*a->data)   * a->size);
283 		a->sorted = realloc(a->sorted, sizeof(*a->sorted) * a->size);
284 		force_assert(a->data);
285 		force_assert(a->sorted);
286 		for (j = a->used; j < a->size; j++) a->data[j] = NULL;
287 	}
288 
289 	ndx = a->used;
290 
291 	/* make sure there is nothing here */
292 	if (a->data[ndx]) a->data[ndx]->fn->free(a->data[ndx]);
293 
294 	a->data[a->used++] = entry;
295 
296 	/* move everything one step to the right */
297 	if (pos != ndx) {
298 		memmove(a->sorted + (pos + 1), a->sorted + (pos), (ndx - pos) * sizeof(*a->sorted));
299 	}
300 
301 	/* insert */
302 	a->sorted[pos] = ndx;
303 
304 	return NULL;
305 }
306 
307 /* replace or insert data (free existing entry) */
308 void array_replace(array *a, data_unset *entry) {
309 	data_unset **old;
310 
311 	force_assert(NULL != entry);
312 	if (NULL != (old = array_find_or_insert(a, entry))) {
313 		force_assert(*old != entry);
314 		(*old)->fn->free(*old);
315 		*old = entry;
316 	}
317 }
318 
319 void array_insert_unique(array *a, data_unset *entry) {
320 	data_unset **old;
321 
322 	force_assert(NULL != entry);
323 	if (NULL != (old = array_find_or_insert(a, entry))) {
324 		force_assert((*old)->type == entry->type);
325 		entry->fn->insert_dup(*old, entry);
326 	}
327 }
328 
329 int array_is_vlist(array *a) {
330 	for (size_t i = 0; i < a->used; ++i) {
331 		data_unset *du = a->data[i];
332 		if (!du->is_index_key || du->type != TYPE_STRING) return 0;
333 	}
334 	return 1;
335 }
336 
337 int array_is_kvany(array *a) {
338 	for (size_t i = 0; i < a->used; ++i) {
339 		data_unset *du = a->data[i];
340 		if (du->is_index_key) return 0;
341 	}
342 	return 1;
343 }
344 
345 int array_is_kvarray(array *a) {
346 	for (size_t i = 0; i < a->used; ++i) {
347 		data_unset *du = a->data[i];
348 		if (du->is_index_key || du->type != TYPE_ARRAY) return 0;
349 	}
350 	return 1;
351 }
352 
353 int array_is_kvstring(array *a) {
354 	for (size_t i = 0; i < a->used; ++i) {
355 		data_unset *du = a->data[i];
356 		if (du->is_index_key || du->type != TYPE_STRING) return 0;
357 	}
358 	return 1;
359 }
360 
361 /* array_match_*() routines follow very similar pattern, but operate on slightly
362  * different data: array key/value, prefix/suffix match, case-insensitive or not
363  * While these could be combined into fewer routines with flags to modify the
364  * behavior, the interface distinctions are useful to add clarity to the code,
365  * and the specialized routines run slightly faster */
366 
367 data_unset *
368 array_match_key_prefix_klen (const array * const a, const char * const s, const size_t slen)
369 {
370     for (size_t i = 0; i < a->used; ++i) {
371         const buffer * const key = a->data[i]->key;
372         const size_t klen = buffer_string_length(key);
373         if (klen <= slen && 0 == memcmp(s, key->ptr, klen))
374             return a->data[i];
375     }
376     return NULL;
377 }
378 
379 data_unset *
380 array_match_key_prefix_nc_klen (const array * const a, const char * const s, const size_t slen)
381 {
382     for (size_t i = 0; i < a->used; ++i) {
383         const buffer * const key = a->data[i]->key;
384         const size_t klen = buffer_string_length(key);
385         if (klen <= slen && 0 == strncasecmp(s, key->ptr, klen))
386             return a->data[i];
387     }
388     return NULL;
389 }
390 
391 data_unset *
392 array_match_key_prefix (const array * const a, const buffer * const b)
393 {
394     return array_match_key_prefix_klen(a, CONST_BUF_LEN(b));
395 }
396 
397 data_unset *
398 array_match_key_prefix_nc (const array * const a, const buffer * const b)
399 {
400     return array_match_key_prefix_nc_klen(a, CONST_BUF_LEN(b));
401 }
402 
403 const buffer *
404 array_match_value_prefix (const array * const a, const buffer * const b)
405 {
406     const size_t blen = buffer_string_length(b);
407 
408     for (size_t i = 0; i < a->used; ++i) {
409         const buffer * const value = ((data_string *)a->data[i])->value;
410         const size_t vlen = buffer_string_length(value);
411         if (vlen <= blen && 0 == memcmp(b->ptr, value->ptr, vlen))
412             return value;
413     }
414     return NULL;
415 }
416 
417 const buffer *
418 array_match_value_prefix_nc (const array * const a, const buffer * const b)
419 {
420     const size_t blen = buffer_string_length(b);
421 
422     for (size_t i = 0; i < a->used; ++i) {
423         const buffer * const value = ((data_string *)a->data[i])->value;
424         const size_t vlen = buffer_string_length(value);
425         if (vlen <= blen && 0 == strncasecmp(b->ptr, value->ptr, vlen))
426             return value;
427     }
428     return NULL;
429 }
430 
431 data_unset *
432 array_match_key_suffix (const array * const a, const buffer * const b)
433 {
434     const size_t blen = buffer_string_length(b);
435     const char * const end = b->ptr + blen;
436 
437     for (size_t i = 0; i < a->used; ++i) {
438         const buffer * const key = a->data[i]->key;
439         const size_t klen = buffer_string_length(key);
440         if (klen <= blen && 0 == memcmp(end - klen, key->ptr, klen))
441             return a->data[i];
442     }
443     return NULL;
444 }
445 
446 data_unset *
447 array_match_key_suffix_nc (const array * const a, const buffer * const b)
448 {
449     const size_t blen = buffer_string_length(b);
450     const char * const end = b->ptr + blen;
451 
452     for (size_t i = 0; i < a->used; ++i) {
453         const buffer * const key = a->data[i]->key;
454         const size_t klen = buffer_string_length(key);
455         if (klen <= blen && 0 == strncasecmp(end - klen, key->ptr, klen))
456             return a->data[i];
457     }
458     return NULL;
459 }
460 
461 const buffer *
462 array_match_value_suffix (const array * const a, const buffer * const b)
463 {
464     const size_t blen = buffer_string_length(b);
465     const char * const end = b->ptr + blen;
466 
467     for (size_t i = 0; i < a->used; ++i) {
468         const buffer * const value = ((data_string *)a->data[i])->value;
469         const size_t vlen = buffer_string_length(value);
470         if (vlen <= blen && 0 == memcmp(end - vlen, value->ptr, vlen))
471             return value;
472     }
473     return NULL;
474 }
475 
476 const buffer *
477 array_match_value_suffix_nc (const array * const a, const buffer * const b)
478 {
479     const size_t blen = buffer_string_length(b);
480     const char * const end = b->ptr + blen;
481 
482     for (size_t i = 0; i < a->used; ++i) {
483         const buffer * const value = ((data_string *)a->data[i])->value;
484         const size_t vlen = buffer_string_length(value);
485         if (vlen <= blen && 0 == strncasecmp(end - vlen, value->ptr, vlen))
486             return value;
487     }
488     return NULL;
489 }
490 
491 data_unset *
492 array_match_path_or_ext (const array * const a, const buffer * const b)
493 {
494     const size_t blen = buffer_string_length(b);
495 
496     for (size_t i = 0; i < a->used; ++i) {
497         /* check extension in the form "^/path" or ".ext$" */
498         const buffer * const key = a->data[i]->key;
499         const size_t klen = buffer_string_length(key);
500         if (klen <= blen
501             && 0 == memcmp((*(key->ptr) == '/' ? b->ptr : b->ptr + blen - klen),
502                            key->ptr, klen))
503             return a->data[i];
504     }
505     return NULL;
506 }
507 
508 
509 
510 
511 
512 #include <stdio.h>
513 
514 void array_print_indent(int depth) {
515 	int i;
516 	for (i = 0; i < depth; i ++) {
517 		fprintf(stdout, "    ");
518 	}
519 }
520 
521 size_t array_get_max_key_length(array *a) {
522 	size_t maxlen, i;
523 
524 	maxlen = 0;
525 	for (i = 0; i < a->used; i ++) {
526 		data_unset *du = a->data[i];
527 		size_t len = buffer_string_length(du->key);
528 
529 		if (len > maxlen) {
530 			maxlen = len;
531 		}
532 	}
533 	return maxlen;
534 }
535 
536 int array_print(array *a, int depth) {
537 	size_t i;
538 	size_t maxlen;
539 	int oneline = 1;
540 
541 	if (a->used > 5) {
542 		oneline = 0;
543 	}
544 	for (i = 0; i < a->used && oneline; i++) {
545 		data_unset *du = a->data[i];
546 		if (!du->is_index_key) {
547 			oneline = 0;
548 			break;
549 		}
550 		switch (du->type) {
551 			case TYPE_INTEGER:
552 			case TYPE_STRING:
553 				break;
554 			default:
555 				oneline = 0;
556 				break;
557 		}
558 	}
559 	if (oneline) {
560 		fprintf(stdout, "(");
561 		for (i = 0; i < a->used; i++) {
562 			data_unset *du = a->data[i];
563 			if (i != 0) {
564 				fprintf(stdout, ", ");
565 			}
566 			du->fn->print(du, depth + 1);
567 		}
568 		fprintf(stdout, ")");
569 		return 0;
570 	}
571 
572 	maxlen = array_get_max_key_length(a);
573 	fprintf(stdout, "(\n");
574 	for (i = 0; i < a->used; i++) {
575 		data_unset *du = a->data[i];
576 		array_print_indent(depth + 1);
577 		if (!du->is_index_key) {
578 			int j;
579 
580 			if (i && (i % 5) == 0) {
581 				fprintf(stdout, "# %zu\n", i);
582 				array_print_indent(depth + 1);
583 			}
584 			fprintf(stdout, "\"%s\"", du->key->ptr);
585 			for (j = maxlen - buffer_string_length(du->key); j > 0; j--) {
586 				fprintf(stdout, " ");
587 			}
588 			fprintf(stdout, " => ");
589 		}
590 		du->fn->print(du, depth + 1);
591 		fprintf(stdout, ",\n");
592 	}
593 	if (!(i && (i - 1 % 5) == 0)) {
594 		array_print_indent(depth + 1);
595 		fprintf(stdout, "# %zu\n", i);
596 	}
597 	array_print_indent(depth);
598 	fprintf(stdout, ")");
599 
600 	return 0;
601 }
602