summaryrefslogtreecommitdiff
path: root/ds.h
blob: dde3496dfc3cfe10ee91d7faf50b1d71cc708e3e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
/*!
\file
\brief VARIOUS DATA STRUCTURES

- dynamic array
- string builder
- string hash table

You can just #include this file -- it's not huge, the functions are all static, and
any reasonable compiler will ignore the unused code.

functions in this file suffixed with _ are not meant to be used outside here, unless you
know what you're doing

NOTE: even on 64-bit platforms, dynamic arrays can only hold ~2<sup>32</sup> elements.

IMPORTANT NOTE: If you are using this with structures containing `long double`s, do
       #define ARR_LONG_DOUBLE
 before including this file
 (otherwise the long doubles will not be aligned.
  this does mean that arrays waste 8 bytes of memory.
  which isnt important unless you're making a lot of arrays.)
*/

#ifndef DS_H_
#define DS_H_

#include <stdint.h>
#include <stdlib.h>
#include <string.h>

typedef uint32_t u32;
typedef uint8_t u8;

typedef union {
	long num;
	void *ptr;
	void (*fnptr)(void);
#ifdef ARR_LONG_DOUBLE
	long
#endif
	double flt;
} ArrMaxAlign;

typedef struct {
	u32 len;
	u32 cap;
	ArrMaxAlign data[];
} ArrHeader;

typedef struct {
	char *str;
	size_t len;
	uint64_t data[];
} StrHashTableSlot;

typedef StrHashTableSlot *StrHashTableSlotPtr;

typedef struct {
	StrHashTableSlot **slots;
	size_t data_size;
	size_t nentries; /* # of filled slots */
} StrHashTable;

typedef struct {
	// dynamic array, including a null byte.
	char *str;
} StrBuilder;


// watch out! do not call this function if arr is NULL.
static ArrHeader *arr_hdr_(void *arr) {
	return (ArrHeader *)((char *)arr - offsetof(ArrHeader, data));
}

static u32 arr_len(const void *arr) {
	return arr ? arr_hdr_((void*)arr)->len : 0;
}

static u32 arr_cap(void *arr) {
	return arr ? arr_hdr_(arr)->cap : 0;
}

static unsigned arr_lenu(void *arr) {
	return (unsigned)arr_len(arr);
}

// grow array to fit one more member
static void *arr_grow1_(void *arr, size_t member_size) {
	if (arr) {
		ArrHeader *hdr = arr_hdr_(arr);
		if (hdr->len >= hdr->cap) {
			u32 new_capacity = hdr->cap * 2;
			ArrHeader *old_hdr = hdr;
			hdr = (ArrHeader *)realloc(old_hdr, sizeof(ArrHeader) + new_capacity * member_size);
			if (hdr) {
				hdr->cap = new_capacity;
			} else {
				free(old_hdr);
				return NULL;
			}
		}
		return hdr->data;
	} else {
		// create a new array
		u32 initial_capacity = 2; // allocate enough space for two members
		ArrHeader *ret = (ArrHeader *)calloc(1, sizeof(ArrHeader) + initial_capacity * member_size);
		if (ret) {
			ret->cap = initial_capacity;
			return ret->data;
		} else {
			return NULL;
		}
	}
}

static void *arr_add_ptr_(void **arr, size_t member_size) {
	u8 *ret;
	*arr = arr_grow1_(*arr, member_size);
	if (*arr) {
		ret = (u8 *)*arr + member_size * (arr_hdr_(*arr)->len++);
		memset(ret, 0, member_size);
	} else {
		ret = NULL;
	}
	return ret;
}

static void arr_reserve_(void **arr, size_t member_size, size_t n) {
	if (n >= U32_MAX-1) { 
		// too big; free arr.
		if (*arr) free(arr_hdr_(*arr));
		*arr = NULL;
		return;
	}
	
	if (n == 0) return;

	if (!*arr) {
		// create a new array with capacity n+1
		// why n+1? i dont know i wrote this a while ago
		ArrHeader *hdr = calloc(1, sizeof(ArrHeader) + (n+1) * member_size);
		if (hdr) {
			hdr->cap = (u32)n+1;
			*arr = hdr->data;
		}
	} else {
		// increase capacity of array
		ArrHeader *hdr = arr_hdr_(*arr);
		u32 curr_cap = hdr->cap;
		if (n > curr_cap) {
			ArrHeader *old_hdr = hdr;
			while (n > curr_cap) {
				if (curr_cap < U32_MAX/2)
					curr_cap *= 2;
				else
					curr_cap = U32_MAX;
			}
			hdr = realloc(hdr, sizeof(ArrHeader) + curr_cap * member_size);
			if (hdr) {
				hdr->cap = curr_cap;
			} else {
				// growing failed
				free(old_hdr);
				*arr = NULL;
				return;
			}
		}
		*arr = hdr->data;
	}
}

static void arr_set_len_(void **arr, size_t member_size, size_t n) {
	arr_reserve_(arr, member_size, n);
	if (*arr) {
		ArrHeader *hdr = arr_hdr_(*arr);
		if (n > hdr->len) {
			// zero new elements
			memset((char *)hdr->data + hdr->len * member_size, 0, (n - hdr->len) * member_size);
		}
		hdr->len = (u32)n;
	}
}

static void *arr_remove_(void *arr, size_t member_size, size_t index) {
	ArrHeader *hdr = arr_hdr_(arr);
	assert(index < hdr->len);
	memmove((char *)arr + index * member_size, (char *)arr + (index+1) * member_size, (hdr->len - (index+1)) * member_size);
	if (--hdr->len == 0) {
		free(hdr);
		return NULL;
	} else {
		return arr;
	}
}

static void *arr_copy_(const void *arr, size_t member_size) {
	void *new_arr = NULL;
	arr_set_len_(&new_arr, member_size, arr_len(arr));
	memcpy(new_arr, arr, member_size * arr_len(arr));
	return new_arr;
}

#ifdef __cplusplus
#define arr_cast_typeof(a) (decltype(a))
#elif defined __GNUC__
#define arr_cast_typeof(a) (__typeof__(a))
#else
#define arr_cast_typeof(a)
#endif

#define arr__join2(a,b) a##b
/// macro used internally
#define arr__join(a,b) arr__join2(a,b)
/// if the array is not NULL, free it and set it to NULL
#define arr_free(a) do { if (a) { free(arr_hdr_(a)); (a) = NULL; } } while (0)
/// a nice alias
#define arr_clear(a) arr_free(a)
/// add an item to the array - if allocation fails, the array will be freed and set to NULL.
/// (how this works: if we can successfully grow the array, increase the length and add the item.)
#define arr_add(a, x) do { if (((a) = arr_cast_typeof(a) arr_grow1_((a), sizeof *(a)))) ((a)[arr_hdr_(a)->len++] = (x)); } while (0)
/// like arr_add, but instead of passing it the value, it returns a pointer to the value. returns NULL if allocation failed.
/// the added item will be zero-initialized.
#define arr_addp(a) arr_cast_typeof(a) arr_add_ptr_((void **)&(a), sizeof *(a))
#define arr_qsort(a, cmp) qsort((a), arr_len(a), sizeof *(a), (cmp))
#define arr_remove_last(a) do { assert(a); if (--arr_hdr_(a)->len == 0) arr_free(a); } while (0)
#define arr_remove(a, i) (void)((a) = arr_remove_((a), sizeof *(a), (i)))
#define arr_insert(a, i, x) do { u32 _index = (i); (a) = arr_cast_typeof(a) arr_grow1_((a), sizeof *(a)); \
	if (a) { memmove((a) + _index + 1, (a) + _index, (arr_len(a) - _index) * sizeof *(a));\
	(a)[_index] = x; \
	++arr_hdr_(a)->len; } } while (0)
#define arr_pop_last(a) ((a)[--arr_hdr_(a)->len])
#define arr_size_in_bytes(a) (arr_len(a) * sizeof *(a))
#define arr_lastp(a) ((a) ? &(a)[arr_len(a)-1] : NULL)
#define arr_copy(a) arr_cast_typeof(a) arr_copy_((a), sizeof *(a))
#define arr_foreach_ptr_end(a, type, var, end) type *end = (a) + arr_len(a); \
	for (type *var = (a); var != end; ++var)
/// Iterate through each element of the array, setting `var` to a pointer to the element.
///
/// You can't use this like, e.g.:
/// ```
/// if (something)
///     arr_foreach_ptr(a, int, i)
///         thing(*i);
/// ```
/// You'll get an error. You will need to use braces because it expands to multiple statements.
/// (we need to name the end pointer something unique, which is why there's that `arr__join` thing
/// we can't just declare it inside the for loop, because type could be something like `char *`.)
#define arr_foreach_ptr(a, type, var) arr_foreach_ptr_end(a, type, var, arr__join(_foreach_end,__LINE__))
/// Reverse array.
///
/// You need to pass in the type because we don't have `typeof` in C yet (coming in C23 supposedly!)
#define arr_reverse(a, type) do { \
	u64 _i, _len = arr_len(a); \
	for (_i = 0; 2*_i < _len; ++_i) { \
		type *_x = &(a)[_i]; \
		type *_y = &(a)[_len-1-_i]; \
		type _tmp; \
		_tmp = *_x; \
		*_x = *_y; \
		*_y = _tmp; \
	} \
	} while (0)

/// Ensure that enough space is allocated for `n` elements.
#define arr_reserve(a, n) arr_reserve_((void **)&(a), sizeof *(a), (n)) 
/// set the length of `a` to `n`, increasing the capacity if necessary.
/// the newly-added elements are zero-initialized.
#define arr_set_len(a, n) arr_set_len_((void **)&(a), sizeof *(a), (n))

#ifndef NDEBUG
static void arr_test(void) {
	u32 *arr = NULL;
	u32 i;
	assert(arr_len(arr) == 0);
	for (i = 0; i < 10000; ++i) {
		arr_add(arr, i*i);
	}
	assert(arr_len(arr) == 10000);
	arr_remove_last(arr);
	assert(arr_len(arr) == 9999);
	for (i = 0; i < arr_len(arr); ++i)
		assert(arr[i] == i*i);
	while (arr_len(arr))
		arr_remove_last(arr);
	assert(arr_len(arr) == 0);
}
#endif

static void str_builder_create(StrBuilder *builder) {
	memset(builder, 0, sizeof *builder);
	arr_add(builder->str, 0);
}

static StrBuilder str_builder_new(void) {
	StrBuilder ret = {0};
	str_builder_create(&ret);
	return ret;
}

static void str_builder_free(StrBuilder *builder) {
	arr_free(builder->str);
}

static void str_builder_clear(StrBuilder *builder) {
	str_builder_free(builder);
	str_builder_create(builder);
}

static void str_builder_append(StrBuilder *builder, const char *s) {
	assert(builder->str);
	
	size_t s_len = strlen(s);
	size_t prev_size = arr_len(builder->str);
	size_t prev_len = prev_size - 1; // null terminator
	// note: this zeroes the newly created elements, so we have a new null terminator
	arr_set_len(builder->str, prev_size + s_len);
	memcpy(builder->str + prev_len, s, s_len);
}

static void str_builder_appendf(StrBuilder *builder, PRINTF_FORMAT_STRING const char *fmt, ...) ATTRIBUTE_PRINTF(2, 3);
static void str_builder_appendf(StrBuilder *builder, const char *fmt, ...) {
	// idk if you can always just pass NULL to vsnprintf
	va_list args;
	char fakebuf[2] = {0};
	va_start(args, fmt);
	int ret = vsnprintf(fakebuf, 1, fmt, args);
	va_end(args);
	
	if (ret < 0) return; // bad format or something
	u32 n = (u32)ret;
	
	size_t prev_size = arr_len(builder->str);
	size_t prev_len = prev_size - 1; // null terminator
	arr_set_len(builder->str, prev_size + n);
	va_start(args, fmt);
	vsnprintf(builder->str + prev_len, n + 1, fmt, args);
	va_end(args);
}

// append n null bytes.
static void str_builder_append_null(StrBuilder *builder, size_t n) {
	arr_set_len(builder->str, arr_len(builder->str) + n);
}

static u32 str_builder_len(StrBuilder *builder) {
	assert(builder->str);
	return arr_len(builder->str) - 1;
}

static char *str_builder_get_ptr(StrBuilder *builder, size_t index) {
	assert(index <= str_builder_len(builder));
	return &builder->str[index];
}

static void str_builder_shrink(StrBuilder *builder, size_t new_len) {
	if (new_len > str_builder_len(builder)) {
		assert(0);
		return;
	}
	arr_set_len(builder->str, new_len + 1);
}


static uint64_t str_hash(const char *str, size_t len) {
	uint64_t hash = 0;
	const char *p = str, *end = str + len;
	for (; p < end; ++p) {
		hash = ((hash * 1664737020647550361 + 123843) << 8) + 2918635993572506131*(uint64_t)*p;
	}
	return hash;
}

static void str_hash_table_create(StrHashTable *t, size_t data_size) {
	t->slots = NULL;
	t->data_size = data_size;
	t->nentries = 0;
}

static StrHashTableSlot **str_hash_table_slot_get(StrHashTableSlot **slots, const char *s, size_t s_len, size_t i) {
	StrHashTableSlot **slot;
	size_t slots_cap = arr_len(slots);
	while (1) {
		assert(i < slots_cap);
		slot = &slots[i];
		if (!*slot) break;
		if (s && (*slot)->str &&
			s_len == (*slot)->len && memcmp(s, (*slot)->str, s_len) == 0)
			break;
		i = (i+1) % slots_cap;
	}
	return slot;
}

static void str_hash_table_grow(StrHashTable *t) {
	size_t slots_cap = arr_len(t->slots);
	if (slots_cap <= 2 * t->nentries) {
		StrHashTableSlot **new_slots = NULL;
		size_t new_slots_cap = slots_cap * 2 + 10;
		arr_set_len(new_slots, new_slots_cap);
		memset(new_slots, 0, new_slots_cap * sizeof *new_slots);
		arr_foreach_ptr(t->slots, StrHashTableSlotPtr, slotp) {
			StrHashTableSlot *slot = *slotp;
			if (slot) {
				uint64_t new_hash = str_hash(slot->str, slot->len);
				StrHashTableSlot **new_slot = str_hash_table_slot_get(new_slots, slot->str, slot->len, new_hash % new_slots_cap);
				*new_slot = slot;
			}
		}
		arr_clear(t->slots);
		t->slots = new_slots;
	}
}

static size_t str_hash_table_slot_size(StrHashTable *t) {
	return sizeof(StrHashTableSlot) + ((t->data_size + sizeof(uint64_t) - 1) / sizeof(uint64_t)) * sizeof(uint64_t);
}

static StrHashTableSlot *str_hash_table_insert_(StrHashTable *t, const char *str, size_t len) {
	size_t slots_cap;
	uint64_t hash;
	StrHashTableSlot **slot;
	str_hash_table_grow(t);
	slots_cap = arr_len(t->slots);
	hash = str_hash(str, len);
	slot = str_hash_table_slot_get(t->slots, str, len, hash % slots_cap);
	if (!*slot) {
		*slot = calloc(1, str_hash_table_slot_size(t));
		char *s = (*slot)->str = calloc(1, len + 1);
		memcpy(s, str, len);
		(*slot)->len = len;
		++t->nentries;
	}
	return *slot;
}

// does NOT check for a null byte.
static void *str_hash_table_insert_with_len(StrHashTable *t, const char *str, size_t len) {
	return str_hash_table_insert_(t, str, len)->data;
}

static void *str_hash_table_insert(StrHashTable *t, const char *str) {
	return str_hash_table_insert_(t, str, strlen(str))->data;
}

static void str_hash_table_clear(StrHashTable *t) {
	arr_foreach_ptr(t->slots, StrHashTableSlotPtr, slotp) {
		if (*slotp) {
			free((*slotp)->str);
		}
		free(*slotp);
	}
	arr_clear(t->slots);
	t->nentries = 0;
}

static StrHashTableSlot *str_hash_table_get_(StrHashTable *t, const char *str, size_t len) {
	size_t nslots = arr_len(t->slots), slot_index;
	if (!nslots) return NULL;
	slot_index = str_hash(str, len) % arr_len(t->slots);
	return *str_hash_table_slot_get(t->slots, str, len, slot_index);
}

static void *str_hash_table_get_with_len(StrHashTable *t, const char *str, size_t len) {
	StrHashTableSlot *slot = str_hash_table_get_(t, str, len);
	if (!slot) return NULL;
	return slot->data;
}

static void *str_hash_table_get(StrHashTable *t, const char *str) {
	return str_hash_table_get_with_len(t, str, strlen(str));
}

#endif