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Diffstat (limited to 'arr.c')
| -rw-r--r-- | arr.c | 214 |
1 files changed, 214 insertions, 0 deletions
@@ -0,0 +1,214 @@ +#ifndef ARR_C_ +#define ARR_C_ +/* +This is free and unencumbered software released into the public domain. +Anyone is free to copy, modify, publish, use, compile, sell, or +distribute this software, either in source code form or as a compiled +binary, for any purpose, commercial or non-commercial, and by any +means. +In jurisdictions that recognize copyright laws, the author or authors +of this software dedicate any and all copyright interest in the +software to the public domain. We make this dedication for the benefit +of the public at large and to the detriment of our heirs and +successors. We intend this dedication to be an overt act of +relinquishment in perpetuity of all present and future rights to this +software under copyright law. +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. +IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR +OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, +ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR +OTHER DEALINGS IN THE SOFTWARE. +For more information, please refer to <http://unlicense.org/> +*/ + +// functions in this file suffixed with _ are not meant to be used outside here, unless you +// know what you're doing + +// IMPORTANT NOTE: If you are using this with structures containing `long double`s, do +// #define ARR_LONG_DOUBLE +// before including this file + +#include <stddef.h> +#if __STDC_VERSION__ >= 201112L +typedef max_align_t ArrMaxAlign; +#else +typedef union { + long num; + void *ptr; + void (*fnptr)(void); +#ifdef ARR_LONG_DOUBLE + long +#endif + double flt; +} ArrMaxAlign; +#endif +#if __STDC_VERSION__ < 199901L && !defined inline +#define inline +#endif + + +typedef struct { + u32 len; + u32 cap; + ArrMaxAlign data[]; +} ArrHeader; + +// watch out! do not call this function if arr is NULL. +static inline ArrHeader *arr_hdr_(void *arr) { + return (ArrHeader *)((char *)arr - offsetof(ArrHeader, data)); +} + +static inline u32 arr_len(void *arr) { + return arr ? arr_hdr_(arr)->len : 0; +} + +static inline 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 inline 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; +} + +#if 0 +// NOT TESTED +static inline void arr_set_len_(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; + } + + if (!*arr) { + // create a new array with capacity n+1 + ArrHeader *hdr = calloc(1, sizeof(ArrHeader) + (n+1) * member_size); + if (hdr) { + hdr->cap = (u32)n+1; + hdr->len = (u32)n; + *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; + } + } + if (n > hdr->len) { + // zero new elements + memset((char *)hdr->data + hdr->len, 0, (n - hdr->len) * member_size); + } + hdr->len = (u32)n; + } +} +#define arr_set_len(a, n) arr_set_len_((void **)&a, sizeof *(a), n) +#endif + +#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 + +// 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) +// 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)) +// set the length of `a` to `n`, increasing the capacity if necessary. +// the newly-added elements are zero-initialized. +#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_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_shrink(a, n) ((void)((a) && (arr_hdr_(a)->len -= (n)))) +#define arr_foreach_backwards(a, var) for (var = arr_lastp(a); var; var = var == (a) ? NULL : var-1) +#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) + +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 // ARR_C_ |