darray.h File Reference

#include <h2o/memory.h>
#include <htils/assert.h>
#include <htils/basictypes.h>

Go to the source code of this file.

Data Structures
struct	h2o_da_header
	The header of a dynamic array. More...

Macros
#define	H2O_DA_HEADER_SIZE
#define	h2o_da_len(darray)   ((darray) ? h2o_da__hdr(darray)->len : 0)
#define	h2o_da_cap(darray)   ((darray) ? h2o_da__hdr(darray)->cap : 0)
#define	h2o_da_new(pool, darray, intitial_capacity)
	Initialize a dynamic array.
#define	h2o_da_append(pool, darray, item)
	Append an item to a dynamic array.
#define	h2o_da_pop(darray)
	Pop an item from a dynamic array.
#define	h2o_da_last(darray)
	Substitute with the last item in a dynamic array.
#define	h2o_da_clear(darray)
	Clears a dynamic array.

Typedefs
typedef struct h2o_da_header	h2o_da_header_t
	The header of a dynamic array.

Functions
static h2o_da_header_t *	h2o_da__hdr (void *h2o_da)
	Get the dynamic array header.

Macro Definition Documentation

h2o_da_append

#define h2o_da_append	(		pool,
			darray,
			item
	)

Value:

  do {                                                                         \
    htils_assert(pool && "Pool cannot be null.");                              \
    htils_assert(darray && "Darray cannot be null.");                          \
    htils_assert(item && "Item cannot be null.");                              \
                                                                               \
    if (!(darray) || h2o_da_len(darray) >= h2o_da_cap(darray)) {               \
      u64 old_capacity = h2o_da_cap(darray);                                   \
      u64 new_capacity =                                                       \
          old_capacity ? old_capacity + old_capacity / 2 + (old_capacity % 2)  \
                       : 8;                                                    \
      u64 old_len = h2o_da_len(darray);                                        \
      u64 alloc_size = H2O_DA_HEADER_SIZE + new_capacity;                      \
                                                                               \
      h2o_da_header_t *header =                                                \
          h2o_mem_alloc_pool((pool), darray, alloc_size);                      \
                                                                               \
      header->cap = new_capacity;                                              \
      header->len = old_len;                                                   \
                                                                               \
      if (darray)                                                              \
        memcpy(header + 1, (darray), old_len * sizeof(*(darray)));             \
                                                                               \
      (darray) = (void *)(header + 1);                                         \
    }                                                                          \
                                                                               \
    (darray)[h2o_da__hdr(darray)->len++] = (item);                             \
  } while (0)

Append an item to a dynamic array.

By incrementing the len, has automatic capacity growing functionality.

Parameters

pool	The memory pool to allocate the dynamic array from.
darray	The dynamic array to append to.
item	The item to append to the dynamic array.

Precondition

pool, darray, and item must be valid and cannot be null.

h2o_da_cap

#define h2o_da_cap

(

darray

)

((darray) ? h2o_da__hdr(darray)->cap : 0)

Gets the capacity of the current dynamic array

h2o_da_clear

#define h2o_da_clear

(

darray

)

Value:

  do {                                                                         \
    if (darray)                                                                \
      h2o_da__hdr(darray)->len = 0;                                            \
  } while (0)

Clears a dynamic array.

By setting its length to 0, if the dynamic array is null, nothing happens.

Parameters

darray

The dynamic array to clear.

H2O_DA_HEADER_SIZE

#define H2O_DA_HEADER_SIZE

Value:

  ((sizeof(h2o_da_header_t) + _Alignof(max_align_t) - 1) &                     \
   ~(_Alignof(max_align_t) - 1))

The size of the header of a dynamic array.

h2o_da_last

#define h2o_da_last

(

darray

)

Value:

  (htils_assert(h2o_da__hdr(darray)->len > 0),                                 \
   (darray)[h2o_da__hdr(darray)->len - 1])

Substitute with the last item in a dynamic array.

Asserts that the length of the dynamic array is larger than 0, then simply gets the last entry.

Parameters

darray

The dynamic array to get the last item from.

h2o_da_len

#define h2o_da_len

(

darray

)

((darray) ? h2o_da__hdr(darray)->len : 0)

Gets the length of the current dynamic array

h2o_da_new

#define h2o_da_new	(		pool,
			darray,
			intitial_capacity
	)

Value:

  do {                                                                         \
    htils_assert(pool && "pool cannot be null.");                              \
    htils_assert(intitial_capacity > 0 &&                                      \
                 "Initial capacity must be greater than 0");                   \
                                                                               \
    u64 capacity = (intitial_capacity);                                        \
    u64 alloc_size = H2O_DA_HEADER_SIZE + capacity;                            \
                                                                               \
    h2o_da_header_t *header = h2o_mem_alloc_pool((pool), darray, alloc_size);  \
    header->cap = capacity;                                                    \
    header->len = 0;                                                           \
    (darray) = (void *)(header + 1);                                           \
  } while (0)

Initialize a dynamic array.

Caluclates the size for the header with H2O_DA_HEADER_SIZE, and the capacity; Allocates the header with initial_capacity, then sets the dynamic array to be the header + 1 offsetting the header.

Parameters

pool	The memory pool to allocate the dynamic array from.
darray	The dynamic array to initialize.
intitial_capacity	The initial capacity of the dynamic array.

Precondition

• pool, and darray must be valid and cannot be null.
• intitial_capacity must be greater than 0.

h2o_da_pop

#define h2o_da_pop

(

darray

)

Value:

  do {                                                                         \
    if (darray && h2o_da__hdr(darray)->len > 0)                                \
      h2o_da__hdr(darray)->len--;                                              \
  } while (0)

Pop an item from a dynamic array.

By simply decrementing its length, if the dynamic array is empty, nothing happens.

Parameters

darray

The dynamic array to pop from.

Typedef Documentation

h2o_da_header_t

typedef struct h2o_da_header h2o_da_header_t

The header of a dynamic array.

Parameters

cap	The capacity of the dynamic array.
len	The length of the dynamic array.

Function Documentation

h2o_da__hdr()

static h2o_da_header_t * h2o_da__hdr ( void *  h2o_da )

inlinestatic

Get the dynamic array header.

Casts the da to cstr * from a dynamic array, by then offsetting by the size of it.

Parameters

da	The dynamic array to get the header from.

Precondition

da must be valid and cannot be null.

Returns

The header of the dynamic array.