g_ptr_array_new ()

GPtrArray *
g_ptr_array_new (void);

Creates a new GPtrArray with a reference count of 1.

g_ptr_array_steal ()

gpointer *
g_ptr_array_steal (GPtrArray *array,
                   gsize *len);

Frees the data in the array and resets the size to zero, while the underlying array is preserved for use elsewhere and returned to the caller.

Note that if the array is NULL terminated this may still return NULL if the length of the array was zero and pdata was not yet allocated.

Even if set, the GDestroyNotify function will never be called on the current contents of the array and the caller is responsible for freeing the array elements.

An example of use:

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g_autoptr(GPtrArray) chunk_buffer = g_ptr_array_new_with_free_func (g_bytes_unref);

// Some part of your application appends a number of chunks to the pointer array.
g_ptr_array_add (chunk_buffer, g_bytes_new_static ("hello", 5));
g_ptr_array_add (chunk_buffer, g_bytes_new_static ("world", 5));

…

// Periodically, the chunks need to be sent as an array-and-length to some
// other part of the program.
GBytes **chunks;
gsize n_chunks;

chunks = g_ptr_array_steal (chunk_buffer, &n_chunks);
for (gsize i = 0; i < n_chunks; i++)
  {
    // Do something with each chunk here, and then free them, since
    // g_ptr_array_steal() transfers ownership of all the elements and the
    // array to the caller.
    …

    g_bytes_unref (chunks[i]);
  }

g_free (chunks);

// After calling g_ptr_array_steal(), the pointer array can be reused for the
// next set of chunks.
g_assert (chunk_buffer->len == 0);

Since: 2.64

g_ptr_array_sized_new ()

GPtrArray *
g_ptr_array_sized_new (guint reserved_size);

Creates a new GPtrArray with reserved_size pointers preallocated and a reference count of 1. This avoids frequent reallocation, if you are going to add many pointers to the array. Note however that the size of the array is still 0.

g_ptr_array_new_with_free_func ()

GPtrArray *
g_ptr_array_new_with_free_func (GDestroyNotify element_free_func);

Creates a new GPtrArray with a reference count of 1 and use element_free_func for freeing each element when the array is destroyed either via g_ptr_array_unref(), when g_ptr_array_free() is called with free_segment set to TRUE or when removing elements.

Since: 2.22

g_ptr_array_copy ()

GPtrArray *
g_ptr_array_copy (GPtrArray *array,
                  GCopyFunc func,
                  gpointer user_data);

Makes a full (deep) copy of a GPtrArray.

func , as a GCopyFunc, takes two arguments, the data to be copied and a user_data pointer. On common processor architectures, it's safe to pass NULL as user_data if the copy function takes only one argument. You may get compiler warnings from this though if compiling with GCC’s -Wcast-function-type warning.

If func is NULL, then only the pointers (and not what they are pointing to) are copied to the new GPtrArray.

The copy of array will have the same GDestroyNotify for its elements as array . The copy will also be NULL terminated if (and only if) the source array is.

Since: 2.62

g_ptr_array_new_full ()

GPtrArray *
g_ptr_array_new_full (guint reserved_size,
                      GDestroyNotify element_free_func);

Creates a new GPtrArray with reserved_size pointers preallocated and a reference count of 1. This avoids frequent reallocation, if you are going to add many pointers to the array. Note however that the size of the array is still 0. It also set element_free_func for freeing each element when the array is destroyed either via g_ptr_array_unref(), when g_ptr_array_free() is called with free_segment set to TRUE or when removing elements.

Since: 2.30

g_ptr_array_new_null_terminated ()

GPtrArray *
g_ptr_array_new_null_terminated (guint reserved_size,
                                 GDestroyNotify element_free_func,
                                 gboolean null_terminated);

Like g_ptr_array_new_full() but also allows to set the array to be NULL terminated. A NULL terminated pointer array has an additional NULL pointer after the last element, beyond the current length.

GPtrArray created by other constructors are not automatically NULL terminated.

Note that if the array 's length is zero and currently no data array is allocated, then pdata will still be NULL. GPtrArray will only NULL terminate pdata, if an actual array is allocated. It does not guarantee that an array is always allocated. In other words, if the length is zero, then pdata may either point to a NULL terminated array of length zero or be NULL.

Since: 2.74

g_ptr_array_set_free_func ()

void
g_ptr_array_set_free_func (GPtrArray *array,
                           GDestroyNotify element_free_func);

Sets a function for freeing each element when array is destroyed either via g_ptr_array_unref(), when g_ptr_array_free() is called with free_segment set to TRUE or when removing elements.

Since: 2.22

g_ptr_array_is_null_terminated ()

gboolean
g_ptr_array_is_null_terminated (GPtrArray *array);

Gets whether the array was constructed as NULL-terminated.

This will only return TRUE for arrays constructed by passing TRUE to the null_terminated argument of g_ptr_array_new_null_terminated(). It will not return TRUE for normal arrays which have had a NULL element appended to them.

Since: 2.74

g_ptr_array_ref ()

GPtrArray *
g_ptr_array_ref (GPtrArray *array);

Atomically increments the reference count of array by one. This function is thread-safe and may be called from any thread.

Since: 2.22

g_ptr_array_unref ()

void
g_ptr_array_unref (GPtrArray *array);

Atomically decrements the reference count of array by one. If the reference count drops to 0, the effect is the same as calling g_ptr_array_free() with free_segment set to TRUE. This function is thread-safe and may be called from any thread.

Since: 2.22

g_ptr_array_add ()

void
g_ptr_array_add (GPtrArray *array,
                 gpointer data);

Adds a pointer to the end of the pointer array. The array will grow in size automatically if necessary.

g_ptr_array_extend ()

void
g_ptr_array_extend (GPtrArray *array_to_extend,
                    GPtrArray *array,
                    GCopyFunc func,
                    gpointer user_data);

Adds all pointers of array to the end of the array array_to_extend . The array will grow in size automatically if needed. array_to_extend is modified in-place.

func , as a GCopyFunc, takes two arguments, the data to be copied and a user_data pointer. On common processor architectures, it's safe to pass NULL as user_data if the copy function takes only one argument. You may get compiler warnings from this though if compiling with GCC’s -Wcast-function-type warning.

If func is NULL, then only the pointers (and not what they are pointing to) are copied to the new GPtrArray.

Whether array_to_extend is NULL terminated stays unchanged by this function.

Since: 2.62

g_ptr_array_extend_and_steal ()

void
g_ptr_array_extend_and_steal (GPtrArray *array_to_extend,
                              GPtrArray *array);

Adds all the pointers in array to the end of array_to_extend , transferring ownership of each element from array to array_to_extend and modifying array_to_extend in-place. array is then freed.

As with g_ptr_array_free(), array will be destroyed if its reference count is 1. If its reference count is higher, it will be decremented and the length of array set to zero.

Since: 2.62

g_ptr_array_insert ()

void
g_ptr_array_insert (GPtrArray *array,
                    gint index_,
                    gpointer data);

Inserts an element into the pointer array at the given index. The array will grow in size automatically if necessary.

Since: 2.40

g_ptr_array_remove ()

gboolean
g_ptr_array_remove (GPtrArray *array,
                    gpointer data);

Removes the first occurrence of the given pointer from the pointer array. The following elements are moved down one place. If array has a non-NULL GDestroyNotify function it is called for the removed element.

It returns TRUE if the pointer was removed, or FALSE if the pointer was not found.

g_ptr_array_remove_index ()

gpointer
g_ptr_array_remove_index (GPtrArray *array,
                          guint index_);

Removes the pointer at the given index from the pointer array. The following elements are moved down one place. If array has a non-NULL GDestroyNotify function it is called for the removed element. If so, the return value from this function will potentially point to freed memory (depending on the GDestroyNotify implementation).

g_ptr_array_remove_fast ()

gboolean
g_ptr_array_remove_fast (GPtrArray *array,
                         gpointer data);

Removes the first occurrence of the given pointer from the pointer array. The last element in the array is used to fill in the space, so this function does not preserve the order of the array. But it is faster than g_ptr_array_remove(). If array has a non-NULL GDestroyNotify function it is called for the removed element.

It returns TRUE if the pointer was removed, or FALSE if the pointer was not found.

g_ptr_array_remove_index_fast ()

gpointer
g_ptr_array_remove_index_fast (GPtrArray *array,
                               guint index_);

Removes the pointer at the given index from the pointer array. The last element in the array is used to fill in the space, so this function does not preserve the order of the array. But it is faster than g_ptr_array_remove_index(). If array has a non-NULL GDestroyNotify function it is called for the removed element. If so, the return value from this function will potentially point to freed memory (depending on the GDestroyNotify implementation).

g_ptr_array_remove_range ()

GPtrArray *
g_ptr_array_remove_range (GPtrArray *array,
                          guint index_,
                          guint length);

Removes the given number of pointers starting at the given index from a GPtrArray. The following elements are moved to close the gap. If array has a non-NULL GDestroyNotify function it is called for the removed elements.

Since: 2.4

g_ptr_array_steal_index ()

gpointer
g_ptr_array_steal_index (GPtrArray *array,
                         guint index_);

Removes the pointer at the given index from the pointer array. The following elements are moved down one place. The GDestroyNotify for array is *not* called on the removed element; ownership is transferred to the caller of this function.

Since: 2.58

g_ptr_array_steal_index_fast ()

gpointer
g_ptr_array_steal_index_fast (GPtrArray *array,
                              guint index_);

Removes the pointer at the given index from the pointer array. The last element in the array is used to fill in the space, so this function does not preserve the order of the array. But it is faster than g_ptr_array_steal_index(). The GDestroyNotify for array is *not* called on the removed element; ownership is transferred to the caller of this function.

Since: 2.58

g_ptr_array_sort ()

void
g_ptr_array_sort (GPtrArray *array,
                  GCompareFunc compare_func);

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

Note that the comparison function for g_ptr_array_sort() doesn't take the pointers from the array as arguments, it takes pointers to the pointers in the array. Here is a full example of usage:

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typedef struct
{
  gchar *name;
  gint size;
} FileListEntry;

static gint
sort_filelist (gconstpointer a, gconstpointer b)
{
  const FileListEntry *entry1 = *((FileListEntry **) a);
  const FileListEntry *entry2 = *((FileListEntry **) b);

  return g_ascii_strcasecmp (entry1->name, entry2->name);
}

…
g_autoptr (GPtrArray) file_list = NULL;

// initialize file_list array and load with many FileListEntry entries
...
// now sort it with
g_ptr_array_sort (file_list, sort_filelist);

This is guaranteed to be a stable sort since version 2.32.

g_ptr_array_sort_with_data ()

void
g_ptr_array_sort_with_data (GPtrArray *array,
                            GCompareDataFunc compare_func,
                            gpointer user_data);

Like g_ptr_array_sort(), but the comparison function has an extra user data argument.

Note that the comparison function for g_ptr_array_sort_with_data() doesn't take the pointers from the array as arguments, it takes pointers to the pointers in the array. Here is a full example of use:

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typedef enum { SORT_NAME, SORT_SIZE } SortMode;

typedef struct
{
  gchar *name;
  gint size;
} FileListEntry;

static gint
sort_filelist (gconstpointer a, gconstpointer b, gpointer user_data)
{
  gint order;
  const SortMode sort_mode = GPOINTER_TO_INT (user_data);
  const FileListEntry *entry1 = *((FileListEntry **) a);
  const FileListEntry *entry2 = *((FileListEntry **) b);

  switch (sort_mode)
    {
    case SORT_NAME:
      order = g_ascii_strcasecmp (entry1->name, entry2->name);
      break;
    case SORT_SIZE:
      order = entry1->size - entry2->size;
      break;
    default:
      order = 0;
      break;
    }
  return order;
}

...
g_autoptr (GPtrArray) file_list = NULL;
SortMode sort_mode;

// initialize file_list array and load with many FileListEntry entries
...
// now sort it with
sort_mode = SORT_NAME;
g_ptr_array_sort_with_data (file_list,
                            sort_filelist,
                            GINT_TO_POINTER (sort_mode));

This is guaranteed to be a stable sort since version 2.32.

g_ptr_array_set_size ()

void
g_ptr_array_set_size (GPtrArray *array,
                      gint length);

Sets the size of the array. When making the array larger, newly-added elements will be set to NULL. When making it smaller, if array has a non-NULL GDestroyNotify function then it will be called for the removed elements.

g_ptr_array_index()

#define             g_ptr_array_index(array,index_)

Returns the pointer at the given index of the pointer array.

This does not perform bounds checking on the given index_ , so you are responsible for checking it against the array length.

g_ptr_array_free ()

gpointer *
g_ptr_array_free (GPtrArray *array,
                  gboolean free_seg);

Frees the memory allocated for the GPtrArray. If free_seg is TRUE it frees the memory block holding the elements as well. Pass FALSE if you want to free the GPtrArray wrapper but preserve the underlying array for use elsewhere. If the reference count of array is greater than one, the GPtrArray wrapper is preserved but the size of array will be set to zero.

If array contents point to dynamically-allocated memory, they should be freed separately if free_seg is TRUE and no GDestroyNotify function has been set for array .

Note that if the array is NULL terminated and free_seg is FALSE then this will always return an allocated NULL terminated buffer. If pdata is previously NULL, a new buffer will be allocated.

This function is not thread-safe. If using a GPtrArray from multiple threads, use only the atomic g_ptr_array_ref() and g_ptr_array_unref() functions.

g_ptr_array_foreach ()

void
g_ptr_array_foreach (GPtrArray *array,
                     GFunc func,
                     gpointer user_data);

Calls a function for each element of a GPtrArray. func must not add elements to or remove elements from the array.

Since: 2.4

g_ptr_array_find ()

gboolean
g_ptr_array_find (GPtrArray *haystack,
                  gconstpointer needle,
                  guint *index_);

Checks whether needle exists in haystack . If the element is found, TRUE is returned and the element’s index is returned in index_ (if non-NULL). Otherwise, FALSE is returned and index_ is undefined. If needle exists multiple times in haystack , the index of the first instance is returned.

This does pointer comparisons only. If you want to use more complex equality checks, such as string comparisons, use g_ptr_array_find_with_equal_func().

[skip]

Since: 2.54

g_ptr_array_find_with_equal_func ()

gboolean
g_ptr_array_find_with_equal_func (GPtrArray *haystack,
                                  gconstpointer needle,
                                  GEqualFunc equal_func,
                                  guint *index_);

Checks whether needle exists in haystack , using the given equal_func . If the element is found, TRUE is returned and the element’s index is returned in index_ (if non-NULL). Otherwise, FALSE is returned and index_ is undefined. If needle exists multiple times in haystack , the index of the first instance is returned.

equal_func is called with the element from the array as its first parameter, and needle as its second parameter. If equal_func is NULL, pointer equality is used.

[skip]

Since: 2.54

struct GPtrArray

struct GPtrArray {
  gpointer *pdata;
  guint	    len;
};

Contains the public fields of a pointer array.