src/lib/array.h

#ifndef ARRAY_H
#define ARRAY_H

/* Array is a buffer accessible using fixed size elements. As long as the
   compiler provides a typeof() operator, the array provides type safety. If
   a wrong type is tried to be added to the array, or if the array's contents
   are tried to be used using a wrong type, the compiler will give a warning.

   Example usage:

   struct foo {
    ARRAY(struct bar) bars;
    ...
   };

   i_array_init(&foo->bars, 10);

   struct bar *bar = array_idx(&foo->bars, 5);
   struct baz *baz = array_idx(&foo->bars, 5); // compiler warning

   If you want to pass an array as a parameter to a function, you'll need to
   create a type for the array using ARRAY_DEFINE_TYPE() and use the type in
   the parameter using ARRAY_TYPE(). Any arrays that you want to be passing
   around, such as structure members as in the above example, must also be
   defined using ARRAY_TYPE() too, rather than ARRAY().

   Example:

   ARRAY_DEFINE_TYPE(foo, struct foo);
   void do_foo(ARRAY_TYPE(foo) *foos) {
    struct foo *foo = array_idx(foos, 0);
   }
   struct foo_manager {
        ARRAY_TYPE(foo) foos; // pedantically, ARRAY(struct foo) is a different type
   };
   // ...
        do_foo(&my_foo_manager->foos); // No compiler warning about mismatched types

*/
#include "array-decl.h"
#include "buffer.h"

#define p_array_init(array, pool, init_count) \
    array_create(array, pool, sizeof(**(array)->v), init_count)
#define i_array_init(array, init_count) \
    p_array_init(array, default_pool, init_count)
#define t_array_init(array, init_count) \
    p_array_init(array, pool_datastack_create(), init_count)

#ifdef HAVE_TYPEOF
#  define ARRAY_TYPE_CAST_CONST(array) \
    (typeof(*(array)->v))
#  define ARRAY_TYPE_CAST_MODIFIABLE(array) \
    (typeof(*(array)->v_modifiable))
#  define ARRAY_TYPE_CHECK(array, data) \
    COMPILE_ERROR_IF_TYPES_NOT_COMPATIBLE( \
        **(array)->v_modifiable, *(data))
#  define ARRAY_TYPES_CHECK(array1, array2) \
    COMPILE_ERROR_IF_TYPES_NOT_COMPATIBLE( \
        **(array1)->v_modifiable, **(array2)->v_modifiable)

#else
#  define ARRAY_TYPE_CAST_CONST(array)
#  define ARRAY_TYPE_CAST_MODIFIABLE(array)
#  define ARRAY_TYPE_CHECK(array, data) 0
#  define ARRAY_TYPES_CHECK(array1, array2) 0
#endif

/* usage: struct foo *foo; array_foreach(foo_arr, foo) { .. } */
#if (defined(__STDC__) && __STDC_VERSION__ >= 199901L)
#  define array_foreach(array, elem) \
    for (const void *elem ## __foreach_end = \
        (const char *)(elem = *(array)->v) + (array)->arr.buffer->used; \
         elem != elem ## __foreach_end; (elem)++)
#  define array_foreach_modifiable(array, elem) \
    for (const void *elem ## _end = \
        (const char *)(elem = ARRAY_TYPE_CAST_MODIFIABLE(array) \
            buffer_get_modifiable_data((array)->arr.buffer, NULL)) + \
            (array)->arr.buffer->used; \
         elem != elem ## _end; (elem)++)
/* Bikeshed: which is better
   array_foreach_elem(array, myvar) { ... use myvar ... }  // not clear myvar is modified
   array_foreach_elem(array, &myvar) { ... use myvar ... } // clearer, as more pass-by-referencey
   Latter is impossible if we want to use the variable name as the base for the other variable names
*/
#  define array_foreach_elem(array, elem) \
    for (unsigned int _foreach_offset = ARRAY_TYPE_CHECK(array, &elem) + \
                COMPILE_ERROR_IF_TRUE(sizeof(elem) > 16)\
             ;                          \
         (_foreach_offset < (array)->arr.buffer->used) &&       \
         (memcpy(&elem, CONST_PTR_OFFSET(*(array)->v, _foreach_offset), sizeof(elem)), TRUE) \
        ;                           \
         _foreach_offset += sizeof(elem)                \
        )

#else
#  define array_foreach(array, elem) \
    for (elem = *(array)->v; \
         elem != CONST_PTR_OFFSET(*(array)->v, (array)->arr.buffer->used); \
         (elem)++)
#  define array_foreach_modifiable(array, elem) \
    for (elem = ARRAY_TYPE_CAST_MODIFIABLE(array) \
            buffer_get_modifiable_data((array)->arr.buffer, NULL); \
         elem != CONST_PTR_OFFSET(*(array)->v, (array)->arr.buffer->used); \
         (elem)++)
#endif

#define array_ptr_to_idx(array, elem) \
    ((elem) - (array)->v[0])
#define array_foreach_idx(array, elem) \
    array_ptr_to_idx(array, elem)

static inline void
array_create_from_buffer_i(struct array *array, buffer_t *buffer,
               size_t element_size)
{
    array->buffer = buffer;
    array->element_size = element_size;
}
#define array_create_from_buffer(array, buffer, element_size) \
    array_create_from_buffer_i(&(array)->arr, buffer, element_size)

static inline void
array_create_i(struct array *array, pool_t pool,
           size_t element_size, unsigned int init_count)
{
    buffer_t *buffer;

        buffer = buffer_create_dynamic(pool, init_count * element_size);
    array_create_from_buffer_i(array, buffer, element_size);
}
#define array_create(array, pool, element_size, init_count) \
    array_create_i(&(array)->arr, pool, element_size, init_count)

static inline void
array_free_i(struct array *array)
{
    buffer_free(&array->buffer);
}
#define array_free(array) \
    array_free_i(&(array)->arr)

static inline bool
array_is_created_i(const struct array *array)
{
    return array->buffer != NULL;
}
#define array_is_created(array) \
    array_is_created_i(&(array)->arr)

static inline pool_t ATTR_PURE
array_get_pool_i(struct array *array)
{
    return buffer_get_pool(array->buffer);
}
#define array_get_pool(array) \
    array_get_pool_i(&(array)->arr)

static inline void
array_clear_i(struct array *array)
{
    buffer_set_used_size(array->buffer, 0);
}
#define array_clear(array) \
    array_clear_i(&(array)->arr)

static inline unsigned int ATTR_PURE
array_count_i(const struct array *array)
{
    return array->buffer->used / array->element_size;
}
#define array_count(array) \
    array_count_i(&(array)->arr)
/* No need for the real count if all we're doing is comparing against 0 */
#define array_is_empty(array) \
    ((array)->arr.buffer->used == 0)
#define array_not_empty(array) \
    ((array)->arr.buffer->used > 0)

static inline void
array_append_i(struct array *array, const void *data, unsigned int count)
{
    buffer_append(array->buffer, data, count * array->element_size);
}

#define array_append(array, data, count) \
    array_append_i(&(array)->arr + ARRAY_TYPE_CHECK(array, data), \
        data, count)

static inline void
array_append_array_i(struct array *dest_array, const struct array *src_array)
{
    i_assert(dest_array->element_size == src_array->element_size);
    buffer_append_buf(dest_array->buffer, src_array->buffer, 0, (size_t)-1);
}
#define array_append_array(dest_array, src_array) \
    array_append_array_i(&(dest_array)->arr + ARRAY_TYPES_CHECK(dest_array, src_array), \
                 &(src_array)->arr)

static inline void
array_insert_i(struct array *array, unsigned int idx,
           const void *data, unsigned int count)
{
    buffer_insert(array->buffer, idx * array->element_size,
              data, count * array->element_size);
}

#define array_insert(array, idx, data, count) \
    array_insert_i(&(array)->arr + ARRAY_TYPE_CHECK(array, data), \
        idx, data, count)

static inline void
array_delete_i(struct array *array, unsigned int idx, unsigned int count)
{
    buffer_delete(array->buffer, idx * array->element_size,
              count * array->element_size);
}
#define array_delete(array, idx, count) \
    array_delete_i(&(array)->arr, idx, count)

static inline const void *
array_get_i(const struct array *array, unsigned int *count_r)
{
    *count_r = array_count_i(array);
    return array->buffer->data;
}
#define array_get(array, count) \
    ARRAY_TYPE_CAST_CONST(array)array_get_i(&(array)->arr, count)

/* Re: i_assert() vs. pure: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=51971#c1 */
static inline const void * ATTR_PURE
array_idx_i(const struct array *array, unsigned int idx)
{
    i_assert(idx * array->element_size < array->buffer->used);
    return CONST_PTR_OFFSET(array->buffer->data, idx * array->element_size);
}
#define array_idx(array, idx) \
    ARRAY_TYPE_CAST_CONST(array)array_idx_i(&(array)->arr, idx)

static inline void *
array_get_modifiable_i(struct array *array, unsigned int *count_r)
{
    *count_r = array_count_i(array);
    return buffer_get_modifiable_data(array->buffer, NULL);
}
#define array_get_modifiable(array, count) \
    ARRAY_TYPE_CAST_MODIFIABLE(array) \
        array_get_modifiable_i(&(array)->arr, count)

void *
array_idx_modifiable_i(const struct array *array, unsigned int idx) ATTR_PURE;
#define array_idx_modifiable(array, idx) \
    ARRAY_TYPE_CAST_MODIFIABLE(array) \
        array_idx_modifiable_i(&(array)->arr, idx)

void *array_idx_get_space_i(struct array *array, unsigned int idx);
#define array_idx_get_space(array, idx) \
    ARRAY_TYPE_CAST_MODIFIABLE(array) \
        array_idx_get_space_i(&(array)->arr, idx)

void array_idx_set_i(struct array *array, unsigned int idx, const void *data);
#define array_idx_set(array, idx, data) \
    array_idx_set_i(&(array)->arr + ARRAY_TYPE_CHECK(array, data), \
        idx, data)

void array_idx_clear_i(struct array *array, unsigned int idx);
#define array_idx_clear(array, idx) \
    array_idx_clear_i(&(array)->arr, idx)

static inline void *
array_append_space_i(struct array *array)
{
    void *data;

    data = buffer_append_space_unsafe(array->buffer, array->element_size);
    memset(data, 0, array->element_size);
    return data;
}
#define array_append_space(array) \
    ARRAY_TYPE_CAST_MODIFIABLE(array)array_append_space_i(&(array)->arr)
#define array_append_zero(array) \
    (void)array_append_space_i(&(array)->arr)

void *array_insert_space_i(struct array *array, unsigned int idx);
#define array_insert_space(array, idx) \
    ARRAY_TYPE_CAST_MODIFIABLE(array) \
        array_insert_space_i(&(array)->arr, idx)

static inline void
array_copy(struct array *dest, unsigned int dest_idx,
       const struct array *src, unsigned int src_idx, unsigned int count)
{
    i_assert(dest->element_size == src->element_size);

    buffer_copy(dest->buffer, dest_idx * dest->element_size,
            src->buffer, src_idx * src->element_size,
            count * dest->element_size);
}

/* Exchange ownership of two arrays, which should have been allocated
   from the same pool/context. Useful for updating an array with a
   replacement. Can also do it with uninitialized arrays (which will
   have .element_size == 0). */
static inline void
array_swap_i(struct array *array1, struct array *array2)
{
    buffer_t *buffer = array1->buffer;
    size_t elsize = array1->element_size;

    array1->buffer = array2->buffer;
    array1->element_size = array2->element_size;
    array2->buffer = buffer;
    array2->element_size = elsize;
}
#define array_swap(array1, array2)                  \
    array_swap_i(&(array1)->arr + ARRAY_TYPES_CHECK(array1, array2), \
             &(array2)->arr)

bool array_cmp_i(const struct array *array1,
         const struct array *array2) ATTR_PURE;
#define array_cmp(array1, array2) \
    array_cmp_i(&(array1)->arr, &(array2)->arr)

/* Test equality via a comparator */
bool array_equal_fn_i(const struct array *array1,
              const struct array *array2,
              int (*cmp)(const void*, const void *)) ATTR_PURE;
#define array_equal_fn(array1, array2, cmp)             \
    array_equal_fn_i(&(array1)->arr +                   \
               ARRAY_TYPES_CHECK(array1, array2),       \
               &(array2)->arr +                 \
               CALLBACK_TYPECHECK(cmp, int (*)(typeof(*(array1)->v), \
                               typeof(*(array2)->v))), \
               (int (*)(const void *, const void *))cmp)
bool array_equal_fn_ctx_i(const struct array *array1,
              const struct array *array2,
              int (*cmp)(const void*, const void *, const void *),
              const void *context) ATTR_PURE;
/* Same, but with a context pointer.
   context can't be void* as ``const typeof(context)'' won't compile,
   so ``const typeof(*context)*'' is required instead, and that requires a
   complete type. */
#define array_equal_fn_ctx(array1, array2, cmp, ctx)            \
    array_equal_fn_ctx_i(&(array1)->arr +               \
                 ARRAY_TYPES_CHECK(array1, array2),     \
                 &(array2)->arr +               \
                 CALLBACK_TYPECHECK(cmp, int (*)(typeof(*(array1)->v), \
                                 typeof(*(array2)->v), \
                                 const typeof(*ctx)*)), \
                 (int (*)(const void *, const void *, const void *))cmp, \
                 ctx)

void array_reverse_i(struct array *array);
#define array_reverse(array) \
    array_reverse_i(&(array)->arr)

void array_sort_i(struct array *array, int (*cmp)(const void *, const void *));
#define array_sort(array, cmp) \
    array_sort_i(&(array)->arr + \
        CALLBACK_TYPECHECK(cmp, int (*)(typeof(*(array)->v), \
                        typeof(*(array)->v))), \
        (int (*)(const void *, const void *))cmp)

void *array_bsearch_i(struct array *array, const void *key,
              int (*cmp)(const void *, const void *));
#define array_bsearch(array, key, cmp) \
    ARRAY_TYPE_CAST_MODIFIABLE(array)array_bsearch_i(&(array)->arr + \
        CALLBACK_TYPECHECK(cmp, int (*)(typeof(const typeof(*key) *), \
                        typeof(*(array)->v))), \
        (const void *)key, (int (*)(const void *, const void *))cmp)

/* Returns pointer to first element for which cmp(key,elem)==0, or NULL */
const void *array_lsearch_i(const struct array *array, const void *key,
                int (*cmp)(const void *, const void *));
static inline void *array_lsearch_modifiable_i(struct array *array, const void *key,
                           int (*cmp)(const void *, const void *))
{
    return (void *)array_lsearch_i(array, key, cmp);
}
#define ARRAY_LSEARCH_CALL(modifiable, array, key, cmp)         \
    array_lsearch##modifiable##i(                   \
        &(array)->arr +                     \
        CALLBACK_TYPECHECK(cmp, int (*)(typeof(const typeof(*key) *), \
                        typeof(*(array)->v))),  \
        (const void *)key,                  \
        (int (*)(const void *, const void *))cmp)
#define array_lsearch(array, key, cmp)                  \
    ARRAY_TYPE_CAST_CONST(array)ARRAY_LSEARCH_CALL(_, array, key, cmp)
#define array_lsearch_modifiable(array, key, cmp)           \
    ARRAY_TYPE_CAST_MODIFIABLE(array)ARRAY_LSEARCH_CALL(_modifiable_, array, key, cmp)

#endif