gstreamer/gst/gststructure.c
David Schleef 91b0389731 hacking. Add value_compare, value_union, and value_intersect functions
Original commit message from CVS:
hacking.  Add value_compare, value_union, and value_intersect functions
2003-11-04 19:00:54 +00:00

882 lines
22 KiB
C

/* GStreamer
* Copyright (C) 2003 David A. Schleef <ds@schleef.org>
*
* gststructure.c: lists of { GQuark, GValue } tuples
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include <gst/gst.h>
#include <gobject/gvaluecollector.h>
//#define G_TYPE_FOURCC G_TYPE_FLOAT
static GType _gst_structure_type;
static void _gst_structure_transform_to_string(const GValue *src_value,
GValue *dest_value);
static void _gst_structure_value_init (GValue *value);
static void _gst_structure_value_free (GValue *value);
static void _gst_structure_value_copy (const GValue *src, GValue *dest);
static gpointer _gst_structure_value_peek_pointer (const GValue *value);
GType gst_structure_get_type(void)
{
return _gst_structure_type;
}
void _gst_structure_initialize(void)
{
static GTypeValueTable type_value_table = {
_gst_structure_value_init,
_gst_structure_value_free,
_gst_structure_value_copy,
_gst_structure_value_peek_pointer,
NULL,
NULL,
NULL,
NULL,
};
static GTypeInfo structure_info = {
0,
NULL,
NULL,
NULL,
NULL,
NULL,
0, /* sizeof(GstStructure), */
0,
NULL, /* _gst_structure_init, */
&type_value_table,
};
_gst_structure_type = g_type_register_static(G_TYPE_BOXED, "GstStructure",
&structure_info, 0);
#if 0
_gst_structure_type = g_boxed_type_register_static("GstStructure",
(GBoxedCopyFunc) gst_structure_copy,
(GBoxedFreeFunc) gst_structure_free);
#endif
g_value_register_transform_func(_gst_structure_type, G_TYPE_STRING,
_gst_structure_transform_to_string);
}
/**
* gst_structure_empty_new:
* @name: name of new structure
*
* Creates a new, empty #GstStructure with the given name.
*
* Returns: a new, empty #GstStructure
*/
GstStructure *gst_structure_empty_new(const gchar *name)
{
GstStructure *structure;
g_return_val_if_fail(name != NULL, NULL);
structure = g_new0(GstStructure, 1);
structure->name = g_quark_from_string(name);
structure->fields = g_array_new(FALSE,TRUE,sizeof(GstStructureField));
return structure;
}
/**
* gst_structure_new:
* @name: name of new structure
* @firstfield: name of first field to set
* @...: additional arguments
*
* Creates a new #GstStructure with the given name. Parses the
* list of variable arguments and sets fields to the values listed.
* Variable arguments should be passed as field name, field type,
* and value. Last variable argument should be NULL.
*
* Returns: a new #GstStructure
*/
GstStructure *gst_structure_new(const gchar *name,
const gchar *firstfield, ...)
{
GstStructure *structure;
va_list varargs;
g_return_val_if_fail(name != NULL, NULL);
va_start(varargs, firstfield);
structure = gst_structure_new_valist(name,firstfield,varargs);
va_end(varargs);
return structure;
}
/**
* gst_structure_new_valist:
* @name: name of new structure
* @firstfield: name of first field to set
* @varags: variable argument list
*
* Creates a new #GstStructure with the given name. Structure fields
* are set according to the varargs in a manner similar to
* @gst_structure_new.
*
* Returns: a new #GstStructure
*/
GstStructure *gst_structure_new_valist(const gchar *name,
const gchar *firstfield, va_list varargs)
{
GstStructure *structure;
g_return_val_if_fail(name != NULL, NULL);
structure = gst_structure_empty_new(name);
gst_structure_set_valist(structure, firstfield, varargs);
return structure;
}
/**
* gst_structure_copy:
* @structure: a #GstStructure to duplicate
*
* Duplicates a #GstStructure and all its fields and values.
*
* Returns: a new #GstStructure.
*/
GstStructure *gst_structure_copy(GstStructure *structure)
{
GstStructure *new_structure;
GstStructureField *field;
int i;
g_return_val_if_fail(structure != NULL, NULL);
new_structure = gst_structure_empty_new(g_quark_to_string(structure->name));
new_structure->fields = g_array_set_size(new_structure->fields,
structure->fields->len);
new_structure->name = structure->name;
for(i=0;i<structure->fields->len;i++){
GstStructureField new_field = { 0 };
field = GST_STRUCTURE_FIELD(structure, i);
new_field.name = field->name;
g_value_init(&new_field.value, G_VALUE_TYPE(&field->value));
g_value_copy(&field->value, &new_field.value);
g_array_append_val(new_structure->fields, new_field);
}
return structure;
}
/**
* gst_structure_free:
* @structure: the #GstStructure to free
*
* Frees a #GstStructure and all its fields and values.
*/
void gst_structure_free(GstStructure *structure)
{
GstStructureField *field;
int i;
return;
g_return_if_fail(structure != NULL);
for(i=0;i<structure->fields->len;i++){
field = GST_STRUCTURE_FIELD(structure, i);
if(G_IS_VALUE(&field->value)){
g_value_unset(&field->value);
}
}
g_free(structure);
}
/**
* gst_structure_get_name:
* @structure: a #GstStructure
*
* Accessor fuction.
*
* Returns: the name of the structure.
*/
const gchar *gst_structure_get_name(GstStructure *structure)
{
g_return_val_if_fail(structure != NULL, NULL);
return g_quark_to_string(structure->name);
}
/**
* gst_structure_set_name:
* @structure: a #GstStructure
* @name: the new name of the structure
*
* Sets the name of the structure to the given name. The string
* provided is copied before being used.
*/
void gst_structure_set_name(GstStructure *structure, const gchar *name)
{
g_return_if_fail(structure != NULL);
g_return_if_fail(name != NULL);
structure->name = g_quark_from_string(name);
}
/**
* gst_structure_id_set_value:
* @structure: a #GstStructure
* @field_id: a #GQuark representing a field
* @value: the new value of the field
*
* Sets the field with the given ID to the provided value. If the field
* does not exist, it is created. If the field exists, the previous
* value is freed.
*/
void gst_structure_id_set_value(GstStructure *structure, GQuark fieldname,
GValue *value)
{
GstStructureField field = { 0 };
g_return_if_fail(structure != NULL);
g_return_if_fail(G_IS_VALUE(value));
field.name = fieldname;
g_value_init(&field.value, G_TYPE_INT);
g_value_copy(value, &field.value);
gst_structure_set_field(structure, &field);
}
/**
* gst_structure_set_value:
* @structure: a #GstStructure
* @field: the name of the field to set
* @value: the new value of the field
*
* Sets the field with the given name to the provided value. If the field
* does not exist, it is created. If the field exists, the previous
* value is freed.
*/
void gst_structure_set_value(GstStructure *structure, const gchar *field,
GValue *value)
{
g_return_if_fail(structure != NULL);
g_return_if_fail(field != NULL);
g_return_if_fail(G_IS_VALUE(value));
gst_structure_id_set_value(structure, g_quark_from_string(field), value);
}
/**
* gst_structure_set:
* @structure: a #GstStructure
* @field: the name of the field to set
* @...: variable arguments
*
* Parses the variable arguments and sets fields accordingly.
* Variable arguments should be in the form field name, field type
* (as a GType), value. The last variable argument should be NULL.
*/
void gst_structure_set(GstStructure *structure, const gchar *field, ...)
{
va_list varargs;
g_return_if_fail(structure != NULL);
va_start(varargs, field);
gst_structure_set_valist(structure,field,varargs);
va_end(varargs);
}
/**
* gst_structure_set:
* @structure: a #GstStructure
* @field: the name of the field to set
* @varargs: variable arguments
*
* va_list form of #gst_structure_set.
*/
void gst_structure_set_valist(GstStructure *structure, const gchar *fieldname,
va_list varargs)
{
GType type;
int i;
double d;
char *s;
g_return_if_fail(structure != NULL);
while(fieldname){
GstStructureField field = { 0 };
field.name = g_quark_from_string(fieldname);
type = va_arg (varargs, GType);
switch(type){
case G_TYPE_INT:
i = va_arg(varargs, int);
g_value_init(&field.value, G_TYPE_INT);
g_value_set_int(&field.value, i);
break;
case G_TYPE_DOUBLE:
d = va_arg(varargs, double);
g_value_init(&field.value, G_TYPE_DOUBLE);
g_value_set_double(&field.value, d);
break;
#if 0
case GST_TYPE_FOURCC:
i = va_arg(varargs, int);
g_value_init(&field.value, G_TYPE_FOURCC);
gst_value_set_fourcc(&field.value, i);
break;
#endif
case G_TYPE_BOOLEAN:
i = va_arg(varargs, int);
g_value_init(&field.value, G_TYPE_BOOLEAN);
g_value_set_boolean(&field.value, i);
break;
case G_TYPE_STRING:
s = va_arg(varargs, char *);
g_value_init(&field.value, G_TYPE_STRING);
g_value_set_string(&field.value, s);
break;
default:
g_assert_not_reached();
break;
}
gst_structure_set_field(structure, &field);
fieldname = va_arg (varargs, gchar *);
}
}
/**
* gst_structure_set_field:
* @structure: a #GstStructure
* @field: the #GstStructureField to set
*
* Sets a field in the structure. If the structure currently contains
* a field with the same name, it is replaced with the provided field.
* Otherwise, the field is added to the structure. The field's value
* is not deeply copied.
*
* This function is intended mainly for internal use. The function
* #gst_structure_set() is recommended instead of this one.
*/
void gst_structure_set_field(GstStructure *structure, GstStructureField *field)
{
GstStructureField *f;
int i;
for(i=0;i<structure->fields->len;i++){
f = GST_STRUCTURE_FIELD(structure, i);
if(f->name == field->name){
g_value_unset(&f->value);
memcpy(f,field,sizeof(GstStructureField));
return;
}
}
g_array_append_val(structure->fields, *field);
}
/**
* gst_structure_id_get_field:
* @structure: a #GstStructure
* @field_id: the GQuark of the field to get
*
* Gets the specified field from the structure. If there is no
* field with the given ID, NULL is returned.
*
* Returns: the #GstStructureField with the given ID
*/
GstStructureField *gst_structure_id_get_field(GstStructure *structure,
GQuark field_id)
{
GstStructureField *field;
int i;
g_return_val_if_fail(structure != NULL, NULL);
for(i=0;i<structure->fields->len;i++){
field = GST_STRUCTURE_FIELD(structure, i);
if(field->name == field_id) return field;
}
return NULL;
}
/**
* gst_structure_get_field:
* @structure: a #GstStructure
* @fieldname: the name of the field to get
*
* Gets the specified field from the structure. If there is no
* field with the given ID, NULL is returned.
*
* Returns: the #GstStructureField with the given name
*/
GstStructureField *
gst_structure_get_field(GstStructure *structure, const gchar *fieldname)
{
g_return_val_if_fail(structure != NULL, NULL);
g_return_val_if_fail(fieldname != NULL, NULL);
return gst_structure_id_get_field(structure,
g_quark_from_string(fieldname));
}
/**
* gst_structure_get_value:
* @structure: a #GstStructure
* @fieldname: the name of the field to get
*
* Accessor function.
*
* Returns: the #GValue corresponding to the field with the given name.
*/
const GValue *
gst_structure_get_value(GstStructure *structure, const gchar *fieldname)
{
GstStructureField *field;
g_return_val_if_fail(structure != NULL, NULL);
g_return_val_if_fail(fieldname != NULL, NULL);
field = gst_structure_get_field(structure, fieldname);
if(field == NULL) return NULL;
return &field->value;
}
#if 0
void gst_structure_get(GstStructure *structure, const gchar *fieldname, ...)
{
}
#endif
/**
* gst_structure_remove_field:
* @structure: a #GstStructure
* @fieldname: the name of the field to remove
*
* Removes the field with the given name. If the field with the given
* name does not exist, the structure is unchanged.
*/
void
gst_structure_remove_field(GstStructure *structure, const gchar *fieldname)
{
GstStructureField *field;
GQuark id;
int i;
g_return_if_fail(structure != NULL);
g_return_if_fail(fieldname != NULL);
id = g_quark_from_string(fieldname);
for(i=0;i<structure->fields->len;i++){
field = GST_STRUCTURE_FIELD(structure, i);
if(field->name == id){
if(G_IS_VALUE(&field->value)){
g_value_unset(&field->value);
}
structure->fields = g_array_remove_index(structure->fields, i);
return;
}
}
}
/**
* gst_structure_get_field_type:
* @structure: a #GstStructure
* @fieldname: the name of the field
*
* Finds the field with the given name, and returns the type of the
* value it contains. If the field is not found, G_TYPE_NONE is
* returned.
*
* Returns: the #GValue of the field
*/
GType
gst_structure_get_field_type(GstStructure *structure, const gchar *fieldname)
{
GstStructureField *field;
g_return_val_if_fail(structure != NULL, G_TYPE_NONE);
g_return_val_if_fail(fieldname != NULL, G_TYPE_NONE);
field = gst_structure_get_field(structure, fieldname);
if(field == NULL) return G_TYPE_NONE;
return G_VALUE_TYPE(&field->value);
}
/**
* gst_structure_n_fields:
* @structure: a #GstStructure
*
* Accessor function.
*
* Returns: the number of fields in the structure
*/
gint
gst_structure_n_fields(GstStructure *structure)
{
g_return_val_if_fail(structure != NULL, 0);
return structure->fields->len;
}
/**
* gst_structure_field_foreach:
* @structure: a #GstStructure
* @func: a function to call for each field
* @user_data: private data
*
* Calls the provided function once for each field in the #GstStructure.
*/
void
gst_structure_field_foreach (GstStructure *structure,
GstStructureForeachFunc func, gpointer user_data)
{
int i;
GstStructureField *field;
for(i=0;i<structure->fields->len;i++){
field = GST_STRUCTURE_FIELD(structure, i);
func (structure, field->name, &field->value, user_data);
}
}
/**
* gst_structure_has_field:
* @structure: a #GstStructure
* @fieldname: the name of a field
*
* Accessor function.
*
* Returns: TRUE if the structure contains a field with the given name
*/
gboolean
gst_structure_has_field(GstStructure *structure, const gchar *fieldname)
{
GstStructureField *field;
g_return_val_if_fail(structure != NULL, 0);
g_return_val_if_fail(fieldname != NULL, 0);
field = gst_structure_get_field(structure, fieldname);
return (field != NULL);
}
/**
* gst_structure_has_field:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @type: the type of a value
*
* Accessor function.
*
* Returns: TRUE if the structure contains a field with the given name and type
*/
gboolean
gst_structure_has_field_typed(GstStructure *structure, const gchar *fieldname,
GType type)
{
GstStructureField *field;
g_return_val_if_fail(structure != NULL, 0);
g_return_val_if_fail(fieldname != NULL, 0);
field = gst_structure_get_field(structure, fieldname);
if(field == NULL) return FALSE;
return (G_VALUE_TYPE(&field->value) == type);
}
/* utility functions */
/**
* gst_structure_get_boolean:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @ptr: a pointer to a #gboolean to set
*
* Sets the boolean pointed to by @ptr corresponding to the value of the
* given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* Returns: TRUE if the value could be set correctly
*/
gboolean
gst_structure_get_boolean(GstStructure *structure, const gchar *fieldname,
gboolean *value)
{
GstStructureField *field;
g_return_val_if_fail(structure != NULL, FALSE);
g_return_val_if_fail(fieldname != NULL, FALSE);
field = gst_structure_get_field(structure, fieldname);
if(field == NULL) return FALSE;
if(!G_VALUE_HOLDS_BOOLEAN(&field->value))return FALSE;
*value = g_value_get_boolean(&field->value);
return TRUE;
}
/**
* gst_structure_get_int:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @ptr: a pointer to an int to set
*
* Sets the int pointed to by @ptr corresponding to the value of the
* given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* Returns: TRUE if the value could be set correctly
*/
gboolean
gst_structure_get_int(GstStructure *structure, const gchar *fieldname,
gint *value)
{
GstStructureField *field;
g_return_val_if_fail(structure != NULL, FALSE);
g_return_val_if_fail(fieldname != NULL, FALSE);
g_return_val_if_fail(value != NULL, FALSE);
field = gst_structure_get_field(structure, fieldname);
if(field == NULL) return FALSE;
if(!G_VALUE_HOLDS_INT(&field->value))return FALSE;
*value = g_value_get_int(&field->value);
return TRUE;
}
/**
* gst_structure_get_fourcc:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @ptr: a pointer to a #GstFourcc to set
*
* Sets the #GstFourcc pointed to by @ptr corresponding to the value of the
* given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* Returns: TRUE if the value could be set correctly
*/
gboolean
gst_structure_get_fourcc(GstStructure *structure, const gchar *fieldname,
guint32 *value)
{
GstStructureField *field;
g_return_val_if_fail(structure != NULL, FALSE);
g_return_val_if_fail(fieldname != NULL, FALSE);
g_return_val_if_fail(value != NULL, FALSE);
field = gst_structure_get_field(structure, fieldname);
if(field == NULL) return FALSE;
if(!G_VALUE_HOLDS_UINT(&field->value))return FALSE;
*value = g_value_get_uint(&field->value);
return TRUE;
}
/**
* gst_structure_get_double:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @ptr: a pointer to a #GstFourcc to set
*
* Sets the double pointed to by @ptr corresponding to the value of the
* given field. Caller is responsible for making sure the field exists
* and has the correct type.
*
* Returns: TRUE if the value could be set correctly
*/
gboolean gst_structure_get_double(GstStructure *structure,
const gchar *fieldname, gdouble *value)
{
GstStructureField *field;
g_return_val_if_fail(structure != NULL, FALSE);
g_return_val_if_fail(fieldname != NULL, FALSE);
g_return_val_if_fail(value != NULL, FALSE);
field = gst_structure_get_field(structure, fieldname);
if(field == NULL) return FALSE;
if(!G_VALUE_HOLDS_DOUBLE(&field->value))return FALSE;
*value = g_value_get_double(&field->value);
return TRUE;
}
/**
* gst_structure_get_string:
* @structure: a #GstStructure
* @fieldname: the name of a field
* @ptr: a pointer to a #GstFourcc to set
*
* Finds the field corresponding to @fieldname, and returns the string
* contained in the field's value. Caller is responsible for making
* sure the field exists and has the correct type.
*
* The string should not be modified, and remains valid until the next
* call to a gst_structure_*() function with the given structure.
*
* Returns: a pointer to the string
*/
const gchar *
gst_structure_get_string(GstStructure *structure, const gchar *fieldname)
{
GstStructureField *field;
g_return_val_if_fail(structure != NULL, NULL);
g_return_val_if_fail(fieldname != NULL, NULL);
field = gst_structure_get_field(structure, fieldname);
if(field == NULL) return FALSE;
if(!G_VALUE_HOLDS_STRING(&field->value))return FALSE;
return g_value_get_string(&field->value);
}
/**
* gst_structure_to_string:
* @structure: a #GstStructure
*
* Converts @structure to a human-readable representation.
*
* Returns: a pointer to string allocated by g_malloc()
*/
gchar *
gst_structure_to_string(GstStructure *structure)
{
GstStructureField *field;
GString *s;
int i;
g_return_val_if_fail(structure != NULL, NULL);
s = g_string_new("");
g_string_append_printf(s, "\"%s\"", g_quark_to_string(structure->name));
for(i=0;i<structure->fields->len;i++){
GValue s_val = { 0 };
field = GST_STRUCTURE_FIELD(structure, i);
g_value_init(&s_val, G_TYPE_STRING);
g_value_transform(&field->value, &s_val);
g_string_append_printf(s, ", %s:%s", g_quark_to_string(field->name),
g_value_get_string(&s_val));
g_value_unset(&s_val);
}
return g_string_free(s, FALSE);
}
/**
* gst_structure_from_string:
* @structure: a #GstStructure
*
* Creates a #GstStructure from a string representation.
*
* Returns: a new #GstStructure
*/
GstStructure *
gst_structure_from_string (const gchar *string)
{
/* FIXME */
g_return_val_if_fail(string != NULL, NULL);
g_assert_not_reached();
return NULL;
}
static void
_gst_structure_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_structure_to_string (src_value->data[0].v_pointer);
}
static void _gst_structure_value_init (GValue *value)
{
value->data[0].v_pointer = gst_structure_empty_new("");
}
static void _gst_structure_value_free (GValue *value)
{
gst_structure_free(value->data[0].v_pointer);
}
static void _gst_structure_value_copy (const GValue *src, GValue *dest)
{
dest->data[0].v_pointer = gst_structure_copy(src->data[0].v_pointer);
}
static gpointer _gst_structure_value_peek_pointer (const GValue *value)
{
return value->data[0].v_pointer;
}