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Byte Arrays

Byte Arrays — arrays of bytes, which grow automatically as elements are added.

Synopsis


#include <glib.h>


            GByteArray;
GByteArray* g_byte_array_new                (void);
GByteArray* g_byte_array_sized_new          (guint reserved_size);
GByteArray* g_byte_array_append             (GByteArray *array,
                                             const guint8 *data,
                                             guint len);
GByteArray* g_byte_array_prepend            (GByteArray *array,
                                             const guint8 *data,
                                             guint len);
GByteArray* g_byte_array_remove_index       (GByteArray *array,
                                             guint index_);
GByteArray* g_byte_array_remove_index_fast  (GByteArray *array,
                                             guint index_);
GByteArray* g_byte_array_remove_range       (GByteArray *array,
                                             guint index_,
                                             guint length);
void        g_byte_array_sort               (GByteArray *array,
                                             GCompareFunc compare_func);
void        g_byte_array_sort_with_data     (GByteArray *array,
                                             GCompareDataFunc compare_func,
                                             gpointer user_data);
GByteArray* g_byte_array_set_size           (GByteArray *array,
                                             guint length);
guint8*     g_byte_array_free               (GByteArray *array,
                                             gboolean free_segment);

Description

GByteArray is based on GArray, to provide arrays of bytes which grow automatically as elements are added.

To create a new GByteArray use g_byte_array_new().

To add elements to a GByteArray, use g_byte_array_append(), and g_byte_array_prepend().

To set the size of a GByteArray, use g_byte_array_set_size().

To free a GByteArray, use g_byte_array_free().

Example 6. Using a GByteArray

  GByteArray *gbarray;
  gint i;

  gbarray = g_byte_array_new ();
  for (i = 0; i < 10000; i++)
    g_byte_array_append (gbarray, (guint8*) "abcd", 4);

  for (i = 0; i < 10000; i++)
    {
      g_assert (gbarray->data[4*i] == 'a');
      g_assert (gbarray->data[4*i+1] == 'b');
      g_assert (gbarray->data[4*i+2] == 'c');
      g_assert (gbarray->data[4*i+3] == 'd');
    }

  g_byte_array_free (gbarray, TRUE);

Details

GByteArray

typedef struct {
  guint8 *data;
  guint	  len;
} GByteArray;

The GByteArray struct allows access to the public fields of a GByteArray.

guint8 *data; a pointer to the element data. The data may be moved as elements are added to the GByteArray.
guint len; the number of elements in the GByteArray.

g_byte_array_new ()

GByteArray* g_byte_array_new                (void);

Creates a new GByteArray.

Returns : the new GByteArray.

g_byte_array_sized_new ()

GByteArray* g_byte_array_sized_new          (guint reserved_size);

Creates a new GByteArray with reserved_size bytes preallocated. This avoids frequent reallocation, if you are going to add many bytes to the array. Note however that the size of the array is still 0.

reserved_size : number of bytes preallocated.
Returns : the new GByteArray.

g_byte_array_append ()

GByteArray* g_byte_array_append             (GByteArray *array,
                                             const guint8 *data,
                                             guint len);

Adds the given bytes to the end of the GByteArray. The array will grow in size automatically if necessary.

array : a GByteArray.
data : the byte data to be added.
len : the number of bytes to add.
Returns : the GByteArray.

g_byte_array_prepend ()

GByteArray* g_byte_array_prepend            (GByteArray *array,
                                             const guint8 *data,
                                             guint len);

Adds the given data to the start of the GByteArray. The array will grow in size automatically if necessary.

array : a GByteArray.
data : the byte data to be added.
len : the number of bytes to add.
Returns : the GByteArray.

g_byte_array_remove_index ()

GByteArray* g_byte_array_remove_index       (GByteArray *array,
                                             guint index_);

Removes the byte at the given index from a GByteArray. The following bytes are moved down one place.

array : a GByteArray.
index_ : the index of the byte to remove.
Returns : the GByteArray.

g_byte_array_remove_index_fast ()

GByteArray* g_byte_array_remove_index_fast  (GByteArray *array,
                                             guint index_);

Removes the byte at the given index from a GByteArray. The last element in the array is used to fill in the space, so this function does not preserve the order of the GByteArray. But it is faster than g_byte_array_remove_index().

array : a GByteArray.
index_ : the index of the byte to remove.
Returns : the GByteArray.

g_byte_array_remove_range ()

GByteArray* g_byte_array_remove_range       (GByteArray *array,
                                             guint index_,
                                             guint length);

Removes the given number of bytes starting at the given index from a GByteArray. The following elements are moved to close the gap.

array : a GByteArray.
index_ : the index of the first byte to remove.
length : the number of bytes to remove.
Returns : the GByteArray.

Since 2.4

g_byte_array_sort ()

void        g_byte_array_sort               (GByteArray *array,
                                             GCompareFunc compare_func);

Sorts a byte array, using compare_func which should be a qsort()-style comparison function (returns -1 for first arg is less than second arg, 0 for equal, 1 if first arg is greater than second arg).

array : a GByteArray.
compare_func : comparison function.

g_byte_array_sort_with_data ()

void        g_byte_array_sort_with_data     (GByteArray *array,
                                             GCompareDataFunc compare_func,
                                             gpointer user_data);

Like g_byte_array_sort(), but the comparison function takes a user data argument.

array : a GByteArray.
compare_func : comparison function.
user_data : data to pass to compare_func.

g_byte_array_set_size ()

GByteArray* g_byte_array_set_size           (GByteArray *array,
                                             guint length);

Sets the size of the GByteArray, expanding it if necessary.

array : a GByteArray.
length : the new size of the GByteArray.
Returns : the GByteArray.

g_byte_array_free ()

guint8*     g_byte_array_free               (GByteArray *array,
                                             gboolean free_segment);

Frees the memory allocated by the GByteArray. If free_segment is TRUE it frees the actual byte data.

array : a GByteArray.
free_segment : if TRUE the actual byte data is freed as well.
Returns :
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