File:  [ELWIX - Embedded LightWeight unIX -] / embedaddon / lighttpd / src / array.c
Revision 1.1.1.3 (vendor branch): download - view: text, annotated - select for diffs - revision graph
Wed Nov 2 10:35:00 2016 UTC (7 years, 11 months ago) by misho
Branches: lighttpd, MAIN
CVS tags: v1_4_41p8, HEAD
lighttpd 1.4.41

    1: #include "first.h"
    2: 
    3: #include "array.h"
    4: #include "buffer.h"
    5: 
    6: #include <string.h>
    7: #include <stdio.h>
    8: #include <stdlib.h>
    9: #include <limits.h>
   10: 
   11: #include <errno.h>
   12: #include <assert.h>
   13: 
   14: #define ARRAY_NOT_FOUND ((size_t)(-1))
   15: 
   16: array *array_init(void) {
   17: 	array *a;
   18: 
   19: 	a = calloc(1, sizeof(*a));
   20: 	force_assert(a);
   21: 
   22: 	return a;
   23: }
   24: 
   25: array *array_init_array(array *src) {
   26: 	size_t i;
   27: 	array *a = array_init();
   28: 
   29: 	if (0 == src->size) return a;
   30: 
   31: 	a->used = src->used;
   32: 	a->size = src->size;
   33: 	a->unique_ndx = src->unique_ndx;
   34: 
   35: 	a->data = malloc(sizeof(*src->data) * src->size);
   36: 	force_assert(NULL != a->data);
   37: 	for (i = 0; i < src->size; i++) {
   38: 		if (src->data[i]) a->data[i] = src->data[i]->copy(src->data[i]);
   39: 		else a->data[i] = NULL;
   40: 	}
   41: 
   42: 	a->sorted = malloc(sizeof(*src->sorted) * src->size);
   43: 	force_assert(NULL != a->sorted);
   44: 	memcpy(a->sorted, src->sorted, sizeof(*src->sorted) * src->size);
   45: 	return a;
   46: }
   47: 
   48: void array_free(array *a) {
   49: 	size_t i;
   50: 	if (!a) return;
   51: 
   52: 	for (i = 0; i < a->size; i++) {
   53: 		if (a->data[i]) a->data[i]->free(a->data[i]);
   54: 	}
   55: 
   56: 	if (a->data) free(a->data);
   57: 	if (a->sorted) free(a->sorted);
   58: 
   59: 	free(a);
   60: }
   61: 
   62: void array_reset(array *a) {
   63: 	size_t i;
   64: 	if (!a) return;
   65: 
   66: 	for (i = 0; i < a->used; i++) {
   67: 		a->data[i]->reset(a->data[i]);
   68: 	}
   69: 
   70: 	a->used = 0;
   71: 	a->unique_ndx = 0;
   72: }
   73: 
   74: data_unset *array_pop(array *a) {
   75: 	data_unset *du;
   76: 
   77: 	force_assert(a->used != 0);
   78: 
   79: 	a->used --;
   80: 	du = a->data[a->used];
   81: 	force_assert(a->sorted[a->used] == a->used); /* only works on "simple" lists */
   82: 	a->data[a->used] = NULL;
   83: 
   84: 	return du;
   85: }
   86: 
   87: /* returns index of element or ARRAY_NOT_FOUND
   88:  * if rndx != NULL it stores the position in a->sorted[] where the key needs
   89:  * to be inserted
   90:  */
   91: static size_t array_get_index(array *a, const char *key, size_t keylen, size_t *rndx) {
   92: 	/* invariant: [lower-1] < key < [upper]
   93: 	 * "virtual elements": [-1] = -INFTY, [a->used] = +INFTY
   94: 	 * also an invariant: 0 <= lower <= upper <= a->used
   95: 	 */
   96: 	size_t lower = 0, upper = a->used;
   97: 	force_assert(upper <= SSIZE_MAX); /* (lower + upper) can't overflow */
   98: 
   99: 	while (lower != upper) {
  100: 		size_t probe = (lower + upper) / 2;
  101: 		int cmp = buffer_caseless_compare(key, keylen, CONST_BUF_LEN(a->data[a->sorted[probe]]->key));
  102: 		assert(lower < upper); /* from loop invariant (lower <= upper) + (lower != upper) */
  103: 		assert((lower <= probe) && (probe < upper)); /* follows from lower < upper */
  104: 
  105: 		if (cmp == 0) {
  106: 			/* found */
  107: 			if (rndx) *rndx = probe;
  108: 			return a->sorted[probe];
  109: 		} else if (cmp < 0) {
  110: 			/* key < [probe] */
  111: 			upper = probe; /* still: lower <= upper */
  112: 		} else {
  113: 			/* key > [probe] */
  114: 			lower = probe + 1; /* still: lower <= upper */
  115: 		}
  116: 	}
  117: 
  118: 	/* not found: [lower-1] < key < [upper] = [lower] ==> insert at [lower] */
  119: 	if (rndx) *rndx = lower;
  120: 	return ARRAY_NOT_FOUND;
  121: }
  122: 
  123: data_unset *array_get_element(array *a, const char *key) {
  124: 	size_t ndx;
  125: 	force_assert(NULL != key);
  126: 
  127: 	if (ARRAY_NOT_FOUND != (ndx = array_get_index(a, key, strlen(key), NULL))) {
  128: 		/* found, return it */
  129: 		return a->data[ndx];
  130: 	}
  131: 
  132: 	return NULL;
  133: }
  134: 
  135: data_unset *array_extract_element(array *a, const char *key) {
  136: 	size_t ndx, pos;
  137: 	force_assert(NULL != key);
  138: 
  139: 	if (ARRAY_NOT_FOUND != (ndx = array_get_index(a, key, strlen(key), &pos))) {
  140: 		/* found */
  141: 		const size_t last_ndx = a->used - 1;
  142: 		data_unset *entry = a->data[ndx];
  143: 
  144: 		/* now we need to swap it with the last element (if it isn't already the last element) */
  145: 		if (ndx != last_ndx) {
  146: 			/* to swap we also need to modify the index in a->sorted - find pos of last_elem there */
  147: 			size_t last_elem_pos;
  148: 			/* last element must be present at the expected position */
  149: 			force_assert(last_ndx == array_get_index(a, CONST_BUF_LEN(a->data[last_ndx]->key), &last_elem_pos));
  150: 
  151: 			/* move entry from last_ndx to ndx */
  152: 			a->data[ndx] = a->data[last_ndx];
  153: 			a->data[last_ndx] = NULL;
  154: 
  155: 			/* fix index entry for moved entry */
  156: 			a->sorted[last_elem_pos] = ndx;
  157: 		} else {
  158: 			a->data[ndx] = NULL;
  159: 		}
  160: 
  161: 		/* remove entry in a->sorted: move everything after pos one step to the left */
  162: 		if (pos != last_ndx) {
  163: 			memmove(a->sorted + pos, a->sorted + pos + 1, (last_ndx - pos) * sizeof(*a->sorted));
  164: 		}
  165: 		a->sorted[last_ndx] = ARRAY_NOT_FOUND;
  166: 		--a->used;
  167: 
  168: 		return entry;
  169: 	}
  170: 
  171: 	return NULL;
  172: }
  173: 
  174: data_unset *array_get_unused_element(array *a, data_type_t t) {
  175: 	data_unset *ds = NULL;
  176: 	unsigned int i;
  177: 
  178: 	for (i = a->used; i < a->size; i++) {
  179: 		if (a->data[i] && a->data[i]->type == t) {
  180: 			ds = a->data[i];
  181: 
  182: 			/* make empty slot at a->used for next insert */
  183: 			a->data[i] = a->data[a->used];
  184: 			a->data[a->used] = NULL;
  185: 
  186: 			return ds;
  187: 		}
  188: 	}
  189: 
  190: 	return NULL;
  191: }
  192: 
  193: void array_set_key_value(array *hdrs, const char *key, size_t key_len, const char *value, size_t val_len) {
  194: 	data_string *ds_dst;
  195: 
  196: 	if (NULL != (ds_dst = (data_string *)array_get_element(hdrs, key))) {
  197: 		buffer_copy_string_len(ds_dst->value, value, val_len);
  198: 		return;
  199: 	}
  200: 
  201: 	if (NULL == (ds_dst = (data_string *)array_get_unused_element(hdrs, TYPE_STRING))) {
  202: 		ds_dst = data_string_init();
  203: 	}
  204: 
  205: 	buffer_copy_string_len(ds_dst->key, key, key_len);
  206: 	buffer_copy_string_len(ds_dst->value, value, val_len);
  207: 	array_insert_unique(hdrs, (data_unset *)ds_dst);
  208: }
  209: 
  210: /* if entry already exists return pointer to existing entry, otherwise insert entry and return NULL */
  211: static data_unset **array_find_or_insert(array *a, data_unset *entry) {
  212: 	size_t ndx, pos, j;
  213: 
  214: 	/* generate unique index if neccesary */
  215: 	if (buffer_is_empty(entry->key) || entry->is_index_key) {
  216: 		buffer_copy_int(entry->key, a->unique_ndx++);
  217: 		entry->is_index_key = 1;
  218: 		force_assert(0 != a->unique_ndx); /* must not wrap or we'll get problems */
  219: 	}
  220: 
  221: 	/* try to find the entry */
  222: 	if (ARRAY_NOT_FOUND != (ndx = array_get_index(a, CONST_BUF_LEN(entry->key), &pos))) {
  223: 		/* found collision, return it */
  224: 		return &a->data[ndx];
  225: 	}
  226: 
  227: 	/* insert */
  228: 
  229: 	/* there couldn't possibly be enough memory to store so many entries */
  230: 	force_assert(a->used + 1 <= SSIZE_MAX);
  231: 
  232: 	if (a->size == 0) {
  233: 		a->size   = 16;
  234: 		a->data   = malloc(sizeof(*a->data)     * a->size);
  235: 		a->sorted = malloc(sizeof(*a->sorted)   * a->size);
  236: 		force_assert(a->data);
  237: 		force_assert(a->sorted);
  238: 		for (j = a->used; j < a->size; j++) a->data[j] = NULL;
  239: 	} else if (a->size == a->used) {
  240: 		a->size  += 16;
  241: 		a->data   = realloc(a->data,   sizeof(*a->data)   * a->size);
  242: 		a->sorted = realloc(a->sorted, sizeof(*a->sorted) * a->size);
  243: 		force_assert(a->data);
  244: 		force_assert(a->sorted);
  245: 		for (j = a->used; j < a->size; j++) a->data[j] = NULL;
  246: 	}
  247: 
  248: 	ndx = a->used;
  249: 
  250: 	/* make sure there is nothing here */
  251: 	if (a->data[ndx]) a->data[ndx]->free(a->data[ndx]);
  252: 
  253: 	a->data[a->used++] = entry;
  254: 
  255: 	/* move everything one step to the right */
  256: 	if (pos != ndx) {
  257: 		memmove(a->sorted + (pos + 1), a->sorted + (pos), (ndx - pos) * sizeof(*a->sorted));
  258: 	}
  259: 
  260: 	/* insert */
  261: 	a->sorted[pos] = ndx;
  262: 
  263: 	return NULL;
  264: }
  265: 
  266: /* replace or insert data (free existing entry) */
  267: void array_replace(array *a, data_unset *entry) {
  268: 	data_unset **old;
  269: 
  270: 	force_assert(NULL != entry);
  271: 	if (NULL != (old = array_find_or_insert(a, entry))) {
  272: 		force_assert(*old != entry);
  273: 		(*old)->free(*old);
  274: 		*old = entry;
  275: 	}
  276: }
  277: 
  278: void array_insert_unique(array *a, data_unset *entry) {
  279: 	data_unset **old;
  280: 
  281: 	force_assert(NULL != entry);
  282: 	if (NULL != (old = array_find_or_insert(a, entry))) {
  283: 		force_assert((*old)->type == entry->type);
  284: 		entry->insert_dup(*old, entry);
  285: 	}
  286: }
  287: 
  288: void array_print_indent(int depth) {
  289: 	int i;
  290: 	for (i = 0; i < depth; i ++) {
  291: 		fprintf(stdout, "    ");
  292: 	}
  293: }
  294: 
  295: size_t array_get_max_key_length(array *a) {
  296: 	size_t maxlen, i;
  297: 
  298: 	maxlen = 0;
  299: 	for (i = 0; i < a->used; i ++) {
  300: 		data_unset *du = a->data[i];
  301: 		size_t len = strlen(du->key->ptr);
  302: 
  303: 		if (len > maxlen) {
  304: 			maxlen = len;
  305: 		}
  306: 	}
  307: 	return maxlen;
  308: }
  309: 
  310: int array_print(array *a, int depth) {
  311: 	size_t i;
  312: 	size_t maxlen;
  313: 	int oneline = 1;
  314: 
  315: 	if (a->used > 5) {
  316: 		oneline = 0;
  317: 	}
  318: 	for (i = 0; i < a->used && oneline; i++) {
  319: 		data_unset *du = a->data[i];
  320: 		if (!du->is_index_key) {
  321: 			oneline = 0;
  322: 			break;
  323: 		}
  324: 		switch (du->type) {
  325: 			case TYPE_INTEGER:
  326: 			case TYPE_STRING:
  327: 			case TYPE_COUNT:
  328: 				break;
  329: 			default:
  330: 				oneline = 0;
  331: 				break;
  332: 		}
  333: 	}
  334: 	if (oneline) {
  335: 		fprintf(stdout, "(");
  336: 		for (i = 0; i < a->used; i++) {
  337: 			data_unset *du = a->data[i];
  338: 			if (i != 0) {
  339: 				fprintf(stdout, ", ");
  340: 			}
  341: 			du->print(du, depth + 1);
  342: 		}
  343: 		fprintf(stdout, ")");
  344: 		return 0;
  345: 	}
  346: 
  347: 	maxlen = array_get_max_key_length(a);
  348: 	fprintf(stdout, "(\n");
  349: 	for (i = 0; i < a->used; i++) {
  350: 		data_unset *du = a->data[i];
  351: 		array_print_indent(depth + 1);
  352: 		if (!du->is_index_key) {
  353: 			int j;
  354: 
  355: 			if (i && (i % 5) == 0) {
  356: 				fprintf(stdout, "# %zu\n", i);
  357: 				array_print_indent(depth + 1);
  358: 			}
  359: 			fprintf(stdout, "\"%s\"", du->key->ptr);
  360: 			for (j = maxlen - strlen(du->key->ptr); j > 0; j --) {
  361: 				fprintf(stdout, " ");
  362: 			}
  363: 			fprintf(stdout, " => ");
  364: 		}
  365: 		du->print(du, depth + 1);
  366: 		fprintf(stdout, ",\n");
  367: 	}
  368: 	if (!(i && (i - 1 % 5) == 0)) {
  369: 		array_print_indent(depth + 1);
  370: 		fprintf(stdout, "# %zu\n", i);
  371: 	}
  372: 	array_print_indent(depth);
  373: 	fprintf(stdout, ")");
  374: 
  375: 	return 0;
  376: }
  377: 
  378: #ifdef DEBUG_ARRAY
  379: int main (int argc, char **argv) {
  380: 	array *a;
  381: 	data_string *ds;
  382: 	data_count *dc;
  383: 
  384: 	UNUSED(argc);
  385: 	UNUSED(argv);
  386: 
  387: 	a = array_init();
  388: 
  389: 	ds = data_string_init();
  390: 	buffer_copy_string_len(ds->key, CONST_STR_LEN("abc"));
  391: 	buffer_copy_string_len(ds->value, CONST_STR_LEN("alfrag"));
  392: 
  393: 	array_insert_unique(a, (data_unset *)ds);
  394: 
  395: 	ds = data_string_init();
  396: 	buffer_copy_string_len(ds->key, CONST_STR_LEN("abc"));
  397: 	buffer_copy_string_len(ds->value, CONST_STR_LEN("hameplman"));
  398: 
  399: 	array_insert_unique(a, (data_unset *)ds);
  400: 
  401: 	ds = data_string_init();
  402: 	buffer_copy_string_len(ds->key, CONST_STR_LEN("123"));
  403: 	buffer_copy_string_len(ds->value, CONST_STR_LEN("alfrag"));
  404: 
  405: 	array_insert_unique(a, (data_unset *)ds);
  406: 
  407: 	dc = data_count_init();
  408: 	buffer_copy_string_len(dc->key, CONST_STR_LEN("def"));
  409: 
  410: 	array_insert_unique(a, (data_unset *)dc);
  411: 
  412: 	dc = data_count_init();
  413: 	buffer_copy_string_len(dc->key, CONST_STR_LEN("def"));
  414: 
  415: 	array_insert_unique(a, (data_unset *)dc);
  416: 
  417: 	array_print(a, 0);
  418: 
  419: 	array_free(a);
  420: 
  421: 	fprintf(stderr, "%d\n",
  422: 	       buffer_caseless_compare(CONST_STR_LEN("Content-Type"), CONST_STR_LEN("Content-type")));
  423: 
  424: 	return 0;
  425: }
  426: #endif

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