/* GStreamer

 * Copyright (C) 2013 Collabora Ltd.

 *   Author: Sebastian Dröge <sebastian.droege@collabora.co.uk>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

/**

 * SECTION:gstcapsfeatures

 * @title: GstCapsFeatures

 * @short_description: A set of features in caps

 * @see_also: #GstCaps

 *

 * #GstCapsFeatures can optionally be set on a #GstCaps to add requirements

 * for additional features for a specific #GstStructure. Caps structures with

 * the same name but with a non-equal set of caps features are not compatible.

 * If a pad supports multiple sets of features it has to add multiple equal

 * structures with different feature sets to the caps.

 *

 * Empty #GstCapsFeatures are equivalent with the #GstCapsFeatures that only

 * contain #GST_CAPS_FEATURE_MEMORY_SYSTEM_MEMORY. ANY #GstCapsFeatures as

 * created by gst_caps_features_new_any() are equal to any other #GstCapsFeatures

 * and can be used to specify that any #GstCapsFeatures would be supported, e.g.

 * for elements that don't touch buffer memory. #GstCaps with ANY #GstCapsFeatures

 * are considered non-fixed and during negotiation some #GstCapsFeatures have

 * to be selected.

 *

 * Examples for caps features would be the requirement of a specific #GstMemory

 * types or the requirement of having a specific #GstMeta on the buffer. Features

 * are given as a string of the format "memory:GstMemoryTypeName" or

 * "meta:GstMetaAPIName".

 *

 * Since: 1.2

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <string.h>

#include "gst_private.h"

#include "gstcapsfeatures.h"

#include <gst/gst.h>

GST_DEBUG_CATEGORY_STATIC (gst_caps_features_debug);

#define GST_CAT_DEFAULT gst_caps_features_debug

struct _GstCapsFeatures

{

  GType type;

  gint *parent_refcount;

  GArray *array;

  gboolean is_any;

};

GType _gst_caps_features_type = 0;

static gint static_caps_features_parent_refcount = G_MAXINT;

GstCapsFeatures *_gst_caps_features_any = NULL;

GstCapsFeatures *_gst_caps_features_memory_system_memory = NULL;

static GQuark _gst_caps_feature_memory_system_memory = 0;

G_DEFINE_BOXED_TYPE (GstCapsFeatures, gst_caps_features,

    gst_caps_features_copy, gst_caps_features_free);

#define IS_MUTABLE(features) \

    (!features->parent_refcount || \

     g_atomic_int_get (features->parent_refcount) == 1)

static void

gst_caps_features_transform_to_string (const GValue * src_value,

    GValue * dest_value);

void

_priv_gst_caps_features_initialize (void)

{

  GST_DEBUG_CATEGORY_INIT (gst_caps_features_debug, "caps-features", 0,

      "GstCapsFeatures debug");

  _gst_caps_features_type = gst_caps_features_get_type ();

  _gst_caps_feature_memory_system_memory =

      g_quark_from_static_string (GST_CAPS_FEATURE_MEMORY_SYSTEM_MEMORY);

  g_value_register_transform_func (_gst_caps_features_type, G_TYPE_STRING,

      gst_caps_features_transform_to_string);

  _gst_caps_features_any = gst_caps_features_new_any ();

  gst_caps_features_set_parent_refcount (_gst_caps_features_any,

      &static_caps_features_parent_refcount);

  _gst_caps_features_memory_system_memory =

      gst_caps_features_new_id (_gst_caps_feature_memory_system_memory, 0);

  gst_caps_features_set_parent_refcount

      (_gst_caps_features_memory_system_memory,

      &static_caps_features_parent_refcount);

}

void

_priv_gst_caps_features_cleanup (void)

{

  gst_caps_features_set_parent_refcount (_gst_caps_features_any, NULL);

  gst_caps_features_free (_gst_caps_features_any);

  _gst_caps_features_any = NULL;

  gst_caps_features_set_parent_refcount

      (_gst_caps_features_memory_system_memory, NULL);

  gst_caps_features_free (_gst_caps_features_memory_system_memory);

  _gst_caps_features_memory_system_memory = NULL;

}

gboolean

gst_is_caps_features (gconstpointer obj)

{

  const GstCapsFeatures *features = obj;

  return (obj != NULL && features->type == _gst_caps_features_type);

}

static gboolean

gst_caps_feature_name_is_valid (const gchar * feature)

{

#ifndef G_DISABLE_CHECKS

  while (TRUE) {

    if (g_ascii_isalpha (*feature))

      feature++;

    else if (*feature == ':')

      break;

    else

      return FALSE;

  }

  if (*feature != ':')

    return FALSE;

  feature++;

  if (*feature == '\0' || !g_ascii_isalpha (*feature))

    return FALSE;

  while (TRUE) {

    if (g_ascii_isalnum (*feature))

      feature++;

    else if (*feature == '\0')

      break;

    else

      return FALSE;

  }

#endif

  return TRUE;

}

/**

 * gst_caps_features_new_empty:

 *

 * Creates a new, empty #GstCapsFeatures.

 *

 * Free-function: gst_caps_features_free

 *

 * Returns: (transfer full): a new, empty #GstCapsFeatures

 *

 * Since: 1.2

 */

GstCapsFeatures *

gst_caps_features_new_empty (void)

{

  GstCapsFeatures *features;

  features = g_slice_new (GstCapsFeatures);

  features->type = _gst_caps_features_type;

  features->parent_refcount = NULL;

  features->array = g_array_new (FALSE, FALSE, sizeof (GQuark));

  features->is_any = FALSE;

  GST_TRACE ("created caps features %p", features);

  return features;

}

/**

 * gst_caps_features_new_any:

 *

 * Creates a new, ANY #GstCapsFeatures. This will be equal

 * to any other #GstCapsFeatures but caps with these are

 * unfixed.

 *

 * Free-function: gst_caps_features_free

 *

 * Returns: (transfer full): a new, ANY #GstCapsFeatures

 *

 * Since: 1.2

 */

GstCapsFeatures *

gst_caps_features_new_any (void)

{

  GstCapsFeatures *features;

  features = gst_caps_features_new_empty ();

  features->is_any = TRUE;

  return features;

}

/**

 * gst_caps_features_new:

 * @feature1: name of first feature to set

 * @...: additional features

 *

 * Creates a new #GstCapsFeatures with the given features.

 * The last argument must be %NULL.

 *

 * Free-function: gst_caps_features_free

 *

 * Returns: (transfer full): a new, empty #GstCapsFeatures

 *

 * Since: 1.2

 */

GstCapsFeatures *

gst_caps_features_new (const gchar * feature1, ...)

{

  GstCapsFeatures *features;

  va_list varargs;

  g_return_val_if_fail (feature1 != NULL, NULL);

  va_start (varargs, feature1);

  features = gst_caps_features_new_valist (feature1, varargs);

  va_end (varargs);

  return features;

}

/**

 * gst_caps_features_new_valist:

 * @feature1: name of first feature to set

 * @varargs: variable argument list

 *

 * Creates a new #GstCapsFeatures with the given features.

 *

 * Free-function: gst_caps_features_free

 *

 * Returns: (transfer full): a new, empty #GstCapsFeatures

 *

 * Since: 1.2

 */

GstCapsFeatures *

gst_caps_features_new_valist (const gchar * feature1, va_list varargs)

{

  GstCapsFeatures *features;

  g_return_val_if_fail (feature1 != NULL, NULL);

  features = gst_caps_features_new_empty ();

  while (feature1) {

    gst_caps_features_add (features, feature1);

    feature1 = va_arg (varargs, const gchar *);

  }

  return features;

}

/**

 * gst_caps_features_new_id:

 * @feature1: name of first feature to set

 * @...: additional features

 *

 * Creates a new #GstCapsFeatures with the given features.

 * The last argument must be 0.

 *

 * Free-function: gst_caps_features_free

 *

 * Returns: (transfer full): a new, empty #GstCapsFeatures

 *

 * Since: 1.2

 */

GstCapsFeatures *

gst_caps_features_new_id (GQuark feature1, ...)

{

  GstCapsFeatures *features;

  va_list varargs;

  g_return_val_if_fail (feature1 != 0, NULL);

  va_start (varargs, feature1);

  features = gst_caps_features_new_id_valist (feature1, varargs);

  va_end (varargs);

  return features;

}

/**

 * gst_caps_features_new_id_valist:

 * @feature1: name of first feature to set

 * @varargs: variable argument list

 *

 * Creates a new #GstCapsFeatures with the given features.

 *

 * Free-function: gst_caps_features_free

 *

 * Returns: (transfer full): a new, empty #GstCapsFeatures

 *

 * Since: 1.2

 */

GstCapsFeatures *

gst_caps_features_new_id_valist (GQuark feature1, va_list varargs)

{

  GstCapsFeatures *features;

  g_return_val_if_fail (feature1 != 0, NULL);

  features = gst_caps_features_new_empty ();

  while (feature1) {

    gst_caps_features_add_id (features, feature1);

    feature1 = va_arg (varargs, GQuark);

  }

  return features;

}

/**

 * gst_caps_features_set_parent_refcount:

 * @features: a #GstCapsFeatures

 * @refcount: (in): a pointer to the parent's refcount

 *

 * Sets the parent_refcount field of #GstCapsFeatures. This field is used to

 * determine whether a caps features is mutable or not. This function should only be

 * called by code implementing parent objects of #GstCapsFeatures, as described in

 * the MT Refcounting section of the design documents.

 *

 * Returns: %TRUE if the parent refcount could be set.

 *

 * Since: 1.2

 */

gboolean

gst_caps_features_set_parent_refcount (GstCapsFeatures * features,

    gint * refcount)

{

  g_return_val_if_fail (features != NULL, FALSE);

  /* if we have a parent_refcount already, we can only clear

   * if with a NULL refcount */

  if (features->parent_refcount) {

    if (refcount != NULL) {

      g_return_val_if_fail (refcount == NULL, FALSE);

      return FALSE;

    }

  } else {

    if (refcount == NULL) {

      g_return_val_if_fail (refcount != NULL, FALSE);

      return FALSE;

    }

  }

  features->parent_refcount = refcount;

  return TRUE;

}

/**

 * gst_caps_features_copy:

 * @features: a #GstCapsFeatures to duplicate

 *

 * Duplicates a #GstCapsFeatures and all its values.

 *

 * Free-function: gst_caps_features_free

 *

 * Returns: (transfer full): a new #GstCapsFeatures.

 *

 * Since: 1.2

 */

GstCapsFeatures *

gst_caps_features_copy (const GstCapsFeatures * features)

{

  GstCapsFeatures *copy;

  guint i, n;

  g_return_val_if_fail (features != NULL, NULL);

  copy = gst_caps_features_new_empty ();

  n = gst_caps_features_get_size (features);

  for (i = 0; i < n; i++)

    gst_caps_features_add_id (copy, gst_caps_features_get_nth_id (features, i));

  copy->is_any = features->is_any;

  return copy;

}

/**

 * gst_caps_features_free:

 * @features: (in) (transfer full): the #GstCapsFeatures to free

 *

 * Frees a #GstCapsFeatures and all its values. The caps features must not

 * have a parent when this function is called.

 *

 * Since: 1.2

 */

void

gst_caps_features_free (GstCapsFeatures * features)

{

  g_return_if_fail (features != NULL);

  g_return_if_fail (features->parent_refcount == NULL);

  g_array_free (features->array, TRUE);

#ifdef USE_POISONING

  memset (features, 0xff, sizeof (GstCapsFeatures));

#endif

  GST_TRACE ("free caps features %p", features);

  g_slice_free (GstCapsFeatures, features);

}

/**

 * gst_caps_features_to_string:

 * @features: a #GstCapsFeatures

 *

 * Converts @features to a human-readable string representation.

 *

 * For debugging purposes its easier to do something like this:

 * |[

 * GST_LOG ("features is %" GST_PTR_FORMAT, features);

 * ]|

 * This prints the features in human readable form.

 *

 * Free-function: g_free

 *

 * Returns: (transfer full): a pointer to string allocated by g_malloc().

 *     g_free() after usage.

 *

 * Since: 1.2

 */

gchar *

gst_caps_features_to_string (const GstCapsFeatures * features)

{

  GString *s;

  g_return_val_if_fail (features != NULL, NULL);

  s = g_string_sized_new (FEATURES_ESTIMATED_STRING_LEN (features));

  priv_gst_caps_features_append_to_gstring (features, s);

  return g_string_free (s, FALSE);

}

void

priv_gst_caps_features_append_to_gstring (const GstCapsFeatures * features,

    GString * s)

{

  guint i, n;

  g_return_if_fail (features != NULL);

  if (features->array->len == 0 && features->is_any) {

    g_string_append (s, "ANY");

    return;

  }

  n = features->array->len;

  for (i = 0; i < n; i++) {

    GQuark *quark = &g_array_index (features->array, GQuark, i);

    g_string_append (s, g_quark_to_string (*quark));

    if (i + 1 < n)

      g_string_append (s, ", ");

  }

}

/**

 * gst_caps_features_from_string:

 * @features: a string representation of a #GstCapsFeatures.

 *

 * Creates a #GstCapsFeatures from a string representation.

 *

 * Free-function: gst_caps_features_free

 *

 * Returns: (transfer full) (nullable): a new #GstCapsFeatures or

 *     %NULL when the string could not be parsed. Free with

 *     gst_caps_features_free() after use.

 *

 * Since: 1.2

 */

GstCapsFeatures *

gst_caps_features_from_string (const gchar * features)

{

  GstCapsFeatures *ret;

  gboolean escape = FALSE;

  const gchar *features_orig = features;

  const gchar *feature;

  ret = gst_caps_features_new_empty ();

  if (!features || *features == '\0')

    return ret;

  if (strcmp (features, "ANY") == 0) {

    ret->is_any = TRUE;

    return ret;

  }

  /* Skip trailing spaces */

  while (*features == ' ')

    features++;

  feature = features;

  while (TRUE) {

    gchar c = *features;

    if (c == '\\') {

      escape = TRUE;

      features++;

      continue;

    } else if ((!escape && c == ',') || c == '\0') {

      guint len = features - feature + 1;

      gchar *tmp;

      gchar *p;

      if (len == 1) {

        g_warning ("Failed deserialize caps features '%s'", features_orig);

        gst_caps_features_free (ret);

        return NULL;

      }

      tmp = g_malloc (len);

      memcpy (tmp, feature, len - 1);

      tmp[len - 1] = '\0';

      p = tmp + len - 1;

      while (*p == ' ') {

        *p = '\0';

        p--;

      }

      if (strstr (tmp, " ") != NULL || *tmp == '\0') {

        g_free (tmp);

        g_warning ("Failed deserialize caps features '%s'", features_orig);

        gst_caps_features_free (ret);

        return NULL;

      }

      gst_caps_features_add (ret, tmp);

      g_free (tmp);

      if (c == '\0')

        break;

      /* Skip to the next value */

      features++;

      while (*features == ' ')

        features++;

      feature = features;

    } else {

      escape = FALSE;

      features++;

    }

  }

  return ret;

}

/**

 * gst_caps_features_get_size:

 * @features: a #GstCapsFeatures.

 *

 * Returns the number of features in @features.

 *

 * Returns: The number of features in @features.

 *

 * Since: 1.2

 */

guint

gst_caps_features_get_size (const GstCapsFeatures * features)

{

  g_return_val_if_fail (features != NULL, 0);

  return features->array->len;

}

/**

 * gst_caps_features_get_nth:

 * @features: a #GstCapsFeatures.

 * @i: index of the feature

 *

 * Returns the @i-th feature of @features.

 *

 * Returns: (nullable): The @i-th feature of @features.

 *

 * Since: 1.2

 */

const gchar *

gst_caps_features_get_nth (const GstCapsFeatures * features, guint i)

{

  const gchar *feature;

  GQuark quark;

  g_return_val_if_fail (features != NULL, NULL);

  quark = gst_caps_features_get_nth_id (features, i);

  if (!quark)

    return NULL;

  feature = g_quark_to_string (quark);

  return feature;

}

/**

 * gst_caps_features_get_nth_id:

 * @features: a #GstCapsFeatures.

 * @i: index of the feature

 *

 * Returns the @i-th feature of @features.

 *

 * Returns: The @i-th feature of @features.

 *

 * Since: 1.2

 */

GQuark

gst_caps_features_get_nth_id (const GstCapsFeatures * features, guint i)

{

  GQuark *quark;

  g_return_val_if_fail (features != NULL, 0);

  g_return_val_if_fail (i < features->array->len, 0);

  quark = &g_array_index (features->array, GQuark, i);

  return *quark;

}

/**

 * gst_caps_features_contains:

 * @features: a #GstCapsFeatures.

 * @feature: a feature

 *

 * Check if @features contains @feature.

 *

 * Returns: %TRUE if @features contains @feature.

 *

 * Since: 1.2

 */

gboolean

gst_caps_features_contains (const GstCapsFeatures * features,

    const gchar * feature)

{

  g_return_val_if_fail (features != NULL, FALSE);

  g_return_val_if_fail (feature != NULL, FALSE);

  return gst_caps_features_contains_id (features,

      g_quark_from_string (feature));

}

/**

 * gst_caps_features_contains_id:

 * @features: a #GstCapsFeatures.

 * @feature: a feature

 *

 * Check if @features contains @feature.

 *

 * Returns: %TRUE if @features contains @feature.

 *

 * Since: 1.2

 */

gboolean

gst_caps_features_contains_id (const GstCapsFeatures * features, GQuark feature)

{

  guint i, n;

  g_return_val_if_fail (features != NULL, FALSE);

  g_return_val_if_fail (feature != 0, FALSE);

  if (features->is_any)

    return TRUE;

  n = features->array->len;

  if (n == 0)

    return feature == _gst_caps_feature_memory_system_memory;

  for (i = 0; i < n; i++) {

    if (gst_caps_features_get_nth_id (features, i) == feature)

      return TRUE;

  }

  return FALSE;

}

/**

 * gst_caps_features_is_equal:

 * @features1: a #GstCapsFeatures.

 * @features2: a #GstCapsFeatures.

 *

 * Check if @features1 and @features2 are equal.

 *

 * Returns: %TRUE if @features1 and @features2 are equal.

 *

 * Since: 1.2

 */

gboolean

gst_caps_features_is_equal (const GstCapsFeatures * features1,

    const GstCapsFeatures * features2)

{

  guint i, n;

  g_return_val_if_fail (features1 != NULL, FALSE);

  g_return_val_if_fail (features2 != NULL, FALSE);

  if (features1->is_any || features2->is_any)

    return TRUE;

  /* Check for the sysmem==empty case */

  if (features1->array->len == 0 && features2->array->len == 0)

    return TRUE;

  if (features1->array->len == 0 && features2->array->len == 1

      && gst_caps_features_contains_id (features2,

          _gst_caps_feature_memory_system_memory))

    return TRUE;

  if (features2->array->len == 0 && features1->array->len == 1

      && gst_caps_features_contains_id (features1,

          _gst_caps_feature_memory_system_memory))

    return TRUE;

  if (features1->array->len != features2->array->len)

    return FALSE;

  n = features1->array->len;

  for (i = 0; i < n; i++)

    if (!gst_caps_features_contains_id (features2,

            gst_caps_features_get_nth_id (features1, i)))

      return FALSE;

  return TRUE;

}

/**

 * gst_caps_features_is_any:

 * @features: a #GstCapsFeatures.

 *

 * Check if @features is %GST_CAPS_FEATURES_ANY.

 *

 * Returns: %TRUE if @features is %GST_CAPS_FEATURES_ANY.

 *

 * Since: 1.2

 */

gboolean

gst_caps_features_is_any (const GstCapsFeatures * features)

{

  g_return_val_if_fail (features != NULL, FALSE);

  return features->is_any;

}

/**

 * gst_caps_features_add:

 * @features: a #GstCapsFeatures.

 * @feature: a feature.

 *

 * Adds @feature to @features.

 *

 * Since: 1.2

 */

void

gst_caps_features_add (GstCapsFeatures * features, const gchar * feature)

{

  g_return_if_fail (features != NULL);

  g_return_if_fail (IS_MUTABLE (features));

  g_return_if_fail (feature != NULL);

  g_return_if_fail (!features->is_any);

  gst_caps_features_add_id (features, g_quark_from_string (feature));

}

/**

 * gst_caps_features_add_id:

 * @features: a #GstCapsFeatures.

 * @feature: a feature.

 *

 * Adds @feature to @features.

 *

 * Since: 1.2

 */

void

gst_caps_features_add_id (GstCapsFeatures * features, GQuark feature)

{

  g_return_if_fail (features != NULL);

  g_return_if_fail (IS_MUTABLE (features));

  g_return_if_fail (feature != 0);

  g_return_if_fail (!features->is_any);

  if (!gst_caps_feature_name_is_valid (g_quark_to_string (feature))) {

    g_warning ("Invalid caps feature name: %s", g_quark_to_string (feature));

    return;

  }

  /* If features is empty it will contain sysmem, however

   * we want to add it explicitely if it is tried to be

   * added as first features

   */

  if (features->array->len > 0

      && gst_caps_features_contains_id (features, feature))

    return;

  g_array_append_val (features->array, feature);

}

/**

 * gst_caps_features_remove:

 * @features: a #GstCapsFeatures.

 * @feature: a feature.

 *

 * Removes @feature from @features.

 *

 * Since: 1.2

 */

void

gst_caps_features_remove (GstCapsFeatures * features, const gchar * feature)

{

  g_return_if_fail (features != NULL);

  g_return_if_fail (IS_MUTABLE (features));

  g_return_if_fail (feature != NULL);

  gst_caps_features_remove_id (features, g_quark_from_string (feature));

}

/**

 * gst_caps_features_remove_id:

 * @features: a #GstCapsFeatures.

 * @feature: a feature.

 *

 * Removes @feature from @features.

 *

 * Since: 1.2

 */

void

gst_caps_features_remove_id (GstCapsFeatures * features, GQuark feature)

{

  guint i, n;

  g_return_if_fail (features != NULL);

  g_return_if_fail (IS_MUTABLE (features));

  g_return_if_fail (feature != 0);

  n = features->array->len;

  for (i = 0; i < n; i++) {

    GQuark quark = gst_caps_features_get_nth_id (features, i);

    if (quark == feature) {

      g_array_remove_index_fast (features->array, i);

      return;

    }

  }

}

static void

gst_caps_features_transform_to_string (const GValue * src_value,

    GValue * dest_value)

{

  g_return_if_fail (src_value != NULL);

  g_return_if_fail (dest_value != NULL);

  dest_value->data[0].v_pointer =

      gst_caps_features_to_string (src_value->data[0].v_pointer);

}