Very simple C array / vector single file implementation, works for any type.
array_grow(array, capacity) /* only reserve memory */
array_resize(array, length) /* only grow and set length */
array_copy(array) /* copies array */
array_push(array, item) /* push one item */
array_pop(array, item) /* pop one item */
array_at(array, index) /* alternative to array[index] */
array_it(array, index) /* alternative to &array[index] */
array_len(array) /* query length */
array_cap(array) /* query capacity */
array_clear(array) /* set length to zero, keep memory */
array_free(array) /* free memory */There is no error handling, BUT a sophisticated amount of errors can happen:
- Different kinds of memory allocation / reallocation
- Out of bounds access
If any error occurs, it is one that should never even happen in the first
place, hence I just exit(1). For that, see Debuggability.
All but the query- and freeing functions handle the NDEBUG preprocessor
definition.
If it is not defined, and an error occurs (out of bounds, allocation) a message
will be printed describing the error and from where it originated, in the form
of file:line-nb:function() array error: message.
If it is defined, the error from where it originated is left out in any case.
Additionally, the out of bounds checking (present in e.g. array_at and
array_it) will be disabled.
As seen in main.c:
#define ARRAY_IMPLEMENTATION
#include "../array.h"
#include <stdio.h>
#include <stdlib.h>
int main(void) {
int *origin = 0; /* initialize to 0! */
printf("push numbers\n");
for(size_t i = 0; i < 10; ++i) {
array_push(origin, rand());
}
int *numbers = array_copy(origin);
printf("length %zu / pointer %p\n", array_len(numbers), numbers);
array_resize(numbers, 5);
printf("/* resize back to %zu elements, capacity is still %zu */\n", array_len(numbers), array_cap(numbers));
printf("/* access by [] */\n");
for(size_t i = 0; i < array_len(numbers); ++i) {
printf("%zu: %u\n", i, numbers[i]);
}
printf("/* access by _at */\n");
for(size_t i = 0; i < array_len(numbers); ++i) {
printf("%zu: %u\n", i, array_at(numbers, i));
}
printf("/* access by _it */\n");
for(size_t i = 0; i < array_len(numbers); ++i) {
printf("%zu: %p->%u\n", i, array_it(numbers, i), *array_it(numbers, i));
}
printf("/* access by pop */\n");
for(size_t i = 0; array_len(numbers); ++i) {
printf("%zu: %u\n", i, array_pop(numbers, i));
}
printf("length %zu\n", array_len(numbers));
array_free(numbers); /* free once done */
array_free(origin);
printf("freed array, verify null: %p\n", numbers);
}Compile with gcc main.c to get the full debug-experience, as described above.
Compile with gcc main.c -DNDEBUG to generate more performant code.
I've kept the actual source and header code in the subdirectory src.
To create the single-header file, use the python script.
I took inspiration from the following: