c_vector.c

#include <stdlib.h>
#include <stdio.h>

#define max(x, y)   ((x) > (y)) ? (x) : (y)

#define C_VECTOR(T) \
typedef struct _c_vector_##T { \
    size_t capacity; \
    size_t size; \
    T *d; \
} c_vector_##T; \
\
c_vector_##T *c_vector_create_##T() { \
    c_vector_##T *v = malloc(sizeof(c_vector_##T)); \
    v->capacity = 0; \
    v->size = 0; \
    v->d = NULL; \
    return v; \
} \
\
void c_vector_destroy_##T(c_vector_##T *v) { \
    if (v->d != NULL) \
        free(v->d); \
    free(v); \
} \
\
void c_vector_append_##T(c_vector_##T *v, T value) { \
    if (v->size >= v->capacity) { \
        v->capacity = max(16, v->capacity * 2); \
        v->d = realloc(v->d, v->capacity * sizeof(T)); \
    } \
    v->d[v->size++] = value; \
}

C_VECTOR(int)
C_VECTOR(double)

int main() {
    c_vector_int *v = c_vector_create_int();
    c_vector_append_int(v, 10);
    c_vector_append_int(v, 20);
    c_vector_append_int(v, 30);
    c_vector_append_int(v, 40);
    c_vector_append_int(v, 50);

    printf("size: %lu capacity: %lu\n", v->size, v->capacity);
    int i;
    for (i = 0; i < v->size; ++i)
        printf("%d\n", v->d[i]);

    c_vector_destroy_int(v);

    c_vector_double *v2 = c_vector_create_double();
    c_vector_append_double(v2, 1.34);
    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);

    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);

    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);

    c_vector_append_double(v2, 5.16);
    c_vector_append_double(v2, 5.16);

    printf("size: %lu capacity: %lu\n", v2->size, v2->capacity);
    for (i = 0; i < v2->size; ++i)
        printf("%f\n", v2->d[i]);

    c_vector_destroy_double(v2);

    return 0;
}