clutter/clutter/clutter-text-buffer.c

767 lines
22 KiB
C

/* clutter-text-buffer.c
* Copyright (C) 2011 Collabora Ltd.
*
* 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.
*
* Author: Stef Walter <stefw@collabora.co.uk>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "clutter-text-buffer.h"
#include "clutter-marshal.h"
#include "clutter-private.h"
#include <string.h>
/**
* SECTION:clutter-text-buffer
* @title: ClutterTextBuffer
* @short_description: Text buffer for ClutterText
*
* The #ClutterTextBuffer class contains the actual text displayed in a
* #ClutterText widget.
*
* A single #ClutterTextBuffer object can be shared by multiple #ClutterText
* widgets which will then share the same text content, but not the cursor
* position, visibility attributes, icon etc.
*
* #ClutterTextBuffer may be derived from. Such a derived class might allow
* text to be stored in an alternate location, such as non-pageable memory,
* useful in the case of important passwords. Or a derived class could
* integrate with an application's concept of undo/redo.
*
* Since: 1.10
*/
/* Initial size of buffer, in bytes */
#define MIN_SIZE 16
enum {
PROP_0,
PROP_TEXT,
PROP_LENGTH,
PROP_MAX_LENGTH,
PROP_LAST
};
static GParamSpec *obj_props[PROP_LAST] = { NULL, };
enum {
INSERTED_TEXT,
DELETED_TEXT,
LAST_SIGNAL
};
static guint signals[LAST_SIGNAL] = { 0 };
struct _ClutterTextBufferPrivate
{
gint max_length;
/* Only valid if this class is not derived */
gchar *normal_text;
gsize normal_text_size;
gsize normal_text_bytes;
guint normal_text_chars;
};
G_DEFINE_TYPE_WITH_PRIVATE (ClutterTextBuffer, clutter_text_buffer, G_TYPE_OBJECT)
/* --------------------------------------------------------------------------------
* DEFAULT IMPLEMENTATIONS OF TEXT BUFFER
*
* These may be overridden by a derived class, behavior may be changed etc...
* The normal_text and normal_text_xxxx fields may not be valid when
* this class is derived from.
*/
/* Overwrite a memory that might contain sensitive information. */
static void
trash_area (gchar *area,
gsize len)
{
volatile gchar *varea = (volatile gchar *)area;
while (len-- > 0)
*varea++ = 0;
}
static const gchar*
clutter_text_buffer_normal_get_text (ClutterTextBuffer *buffer,
gsize *n_bytes)
{
if (n_bytes)
*n_bytes = buffer->priv->normal_text_bytes;
if (!buffer->priv->normal_text)
return "";
return buffer->priv->normal_text;
}
static guint
clutter_text_buffer_normal_get_length (ClutterTextBuffer *buffer)
{
return buffer->priv->normal_text_chars;
}
static guint
clutter_text_buffer_normal_insert_text (ClutterTextBuffer *buffer,
guint position,
const gchar *chars,
guint n_chars)
{
ClutterTextBufferPrivate *pv = buffer->priv;
gsize prev_size;
gsize n_bytes;
gsize at;
n_bytes = g_utf8_offset_to_pointer (chars, n_chars) - chars;
/* Need more memory */
if (n_bytes + pv->normal_text_bytes + 1 > pv->normal_text_size)
{
gchar *et_new;
prev_size = pv->normal_text_size;
/* Calculate our new buffer size */
while (n_bytes + pv->normal_text_bytes + 1 > pv->normal_text_size)
{
if (pv->normal_text_size == 0)
pv->normal_text_size = MIN_SIZE;
else
{
if (2 * pv->normal_text_size < CLUTTER_TEXT_BUFFER_MAX_SIZE)
pv->normal_text_size *= 2;
else
{
pv->normal_text_size = CLUTTER_TEXT_BUFFER_MAX_SIZE;
if (n_bytes > pv->normal_text_size - pv->normal_text_bytes - 1)
{
n_bytes = pv->normal_text_size - pv->normal_text_bytes - 1;
n_bytes = g_utf8_find_prev_char (chars, chars + n_bytes + 1) - chars;
n_chars = g_utf8_strlen (chars, n_bytes);
}
break;
}
}
}
/* Could be a password, so can't leave stuff in memory. */
et_new = g_malloc (pv->normal_text_size);
memcpy (et_new, pv->normal_text, MIN (prev_size, pv->normal_text_size));
trash_area (pv->normal_text, prev_size);
g_free (pv->normal_text);
pv->normal_text = et_new;
}
/* Actual text insertion */
at = g_utf8_offset_to_pointer (pv->normal_text, position) - pv->normal_text;
g_memmove (pv->normal_text + at + n_bytes, pv->normal_text + at, pv->normal_text_bytes - at);
memcpy (pv->normal_text + at, chars, n_bytes);
/* Book keeping */
pv->normal_text_bytes += n_bytes;
pv->normal_text_chars += n_chars;
pv->normal_text[pv->normal_text_bytes] = '\0';
clutter_text_buffer_emit_inserted_text (buffer, position, chars, n_chars);
return n_chars;
}
static guint
clutter_text_buffer_normal_delete_text (ClutterTextBuffer *buffer,
guint position,
guint n_chars)
{
ClutterTextBufferPrivate *pv = buffer->priv;
gsize start, end;
if (position > pv->normal_text_chars)
position = pv->normal_text_chars;
if (position + n_chars > pv->normal_text_chars)
n_chars = pv->normal_text_chars - position;
if (n_chars > 0)
{
start = g_utf8_offset_to_pointer (pv->normal_text, position) - pv->normal_text;
end = g_utf8_offset_to_pointer (pv->normal_text, position + n_chars) - pv->normal_text;
g_memmove (pv->normal_text + start, pv->normal_text + end, pv->normal_text_bytes + 1 - end);
pv->normal_text_chars -= n_chars;
pv->normal_text_bytes -= (end - start);
/*
* Could be a password, make sure we don't leave anything sensitive after
* the terminating zero. Note, that the terminating zero already trashed
* one byte.
*/
trash_area (pv->normal_text + pv->normal_text_bytes + 1, end - start - 1);
clutter_text_buffer_emit_deleted_text (buffer, position, n_chars);
}
return n_chars;
}
/* --------------------------------------------------------------------------------
*
*/
static void
clutter_text_buffer_real_inserted_text (ClutterTextBuffer *buffer,
guint position,
const gchar *chars,
guint n_chars)
{
g_object_notify (G_OBJECT (buffer), "text");
g_object_notify (G_OBJECT (buffer), "length");
}
static void
clutter_text_buffer_real_deleted_text (ClutterTextBuffer *buffer,
guint position,
guint n_chars)
{
g_object_notify (G_OBJECT (buffer), "text");
g_object_notify (G_OBJECT (buffer), "length");
}
/* --------------------------------------------------------------------------------
*
*/
static void
clutter_text_buffer_init (ClutterTextBuffer *self)
{
self->priv = clutter_text_buffer_get_instance_private (self);
self->priv->normal_text = NULL;
self->priv->normal_text_chars = 0;
self->priv->normal_text_bytes = 0;
self->priv->normal_text_size = 0;
}
static void
clutter_text_buffer_finalize (GObject *obj)
{
ClutterTextBuffer *buffer = CLUTTER_TEXT_BUFFER (obj);
ClutterTextBufferPrivate *pv = buffer->priv;
if (pv->normal_text)
{
trash_area (pv->normal_text, pv->normal_text_size);
g_free (pv->normal_text);
pv->normal_text = NULL;
pv->normal_text_bytes = pv->normal_text_size = 0;
pv->normal_text_chars = 0;
}
G_OBJECT_CLASS (clutter_text_buffer_parent_class)->finalize (obj);
}
static void
clutter_text_buffer_set_property (GObject *obj,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
ClutterTextBuffer *buffer = CLUTTER_TEXT_BUFFER (obj);
switch (prop_id)
{
case PROP_MAX_LENGTH:
clutter_text_buffer_set_max_length (buffer, g_value_get_int (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (obj, prop_id, pspec);
break;
}
}
static void
clutter_text_buffer_get_property (GObject *obj,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
ClutterTextBuffer *buffer = CLUTTER_TEXT_BUFFER (obj);
switch (prop_id)
{
case PROP_TEXT:
g_value_set_string (value, clutter_text_buffer_get_text (buffer));
break;
case PROP_LENGTH:
g_value_set_uint (value, clutter_text_buffer_get_length (buffer));
break;
case PROP_MAX_LENGTH:
g_value_set_int (value, clutter_text_buffer_get_max_length (buffer));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (obj, prop_id, pspec);
break;
}
}
static void
clutter_text_buffer_class_init (ClutterTextBufferClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
gobject_class->finalize = clutter_text_buffer_finalize;
gobject_class->set_property = clutter_text_buffer_set_property;
gobject_class->get_property = clutter_text_buffer_get_property;
klass->get_text = clutter_text_buffer_normal_get_text;
klass->get_length = clutter_text_buffer_normal_get_length;
klass->insert_text = clutter_text_buffer_normal_insert_text;
klass->delete_text = clutter_text_buffer_normal_delete_text;
klass->inserted_text = clutter_text_buffer_real_inserted_text;
klass->deleted_text = clutter_text_buffer_real_deleted_text;
/**
* ClutterTextBuffer:text:
*
* The contents of the buffer.
*
* Since: 1.10
*/
obj_props[PROP_TEXT] =
g_param_spec_string ("text",
P_("Text"),
P_("The contents of the buffer"),
"",
G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
/**
* ClutterTextBuffer:length:
*
* The length (in characters) of the text in buffer.
*
* Since: 1.10
*/
obj_props[PROP_LENGTH] =
g_param_spec_uint ("length",
P_("Text length"),
P_("Length of the text currently in the buffer"),
0, CLUTTER_TEXT_BUFFER_MAX_SIZE, 0,
G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
/**
* ClutterTextBuffer:max-length:
*
* The maximum length (in characters) of the text in the buffer.
*
* Since: 1.10
*/
obj_props[PROP_MAX_LENGTH] =
g_param_spec_int ("max-length",
P_("Maximum length"),
P_("Maximum number of characters for this entry. Zero if no maximum"),
0, CLUTTER_TEXT_BUFFER_MAX_SIZE, 0,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
g_object_class_install_properties (gobject_class, PROP_LAST, obj_props);
/**
* ClutterTextBuffer::inserted-text:
* @buffer: a #ClutterTextBuffer
* @position: the position the text was inserted at.
* @chars: The text that was inserted.
* @n_chars: The number of characters that were inserted.
*
* This signal is emitted after text is inserted into the buffer.
*
* Since: 1.10
*/
signals[INSERTED_TEXT] =
g_signal_new (I_("inserted-text"),
CLUTTER_TYPE_TEXT_BUFFER,
G_SIGNAL_RUN_FIRST,
G_STRUCT_OFFSET (ClutterTextBufferClass, inserted_text),
NULL, NULL,
_clutter_marshal_VOID__UINT_STRING_UINT,
G_TYPE_NONE, 3,
G_TYPE_UINT,
G_TYPE_STRING,
G_TYPE_UINT);
/**
* ClutterTextBuffer::deleted-text:
* @buffer: a #ClutterTextBuffer
* @position: the position the text was deleted at.
* @n_chars: The number of characters that were deleted.
*
* This signal is emitted after text is deleted from the buffer.
*
* Since: 1.10
*/
signals[DELETED_TEXT] =
g_signal_new (I_("deleted-text"),
CLUTTER_TYPE_TEXT_BUFFER,
G_SIGNAL_RUN_FIRST,
G_STRUCT_OFFSET (ClutterTextBufferClass, deleted_text),
NULL, NULL,
_clutter_marshal_VOID__UINT_UINT,
G_TYPE_NONE, 2,
G_TYPE_UINT,
G_TYPE_UINT);
}
/* --------------------------------------------------------------------------------
*
*/
/**
* clutter_text_buffer_new:
*
* Create a new ClutterTextBuffer object.
*
* Return value: A new ClutterTextBuffer object.
*
* Since: 1.10
**/
ClutterTextBuffer*
clutter_text_buffer_new (void)
{
return g_object_new (CLUTTER_TYPE_TEXT_BUFFER, NULL);
}
/**
* clutter_text_buffer_new_with_text:
* @text: (allow-none): initial buffer text
* @text_len: initial buffer text length, or -1 for null-terminated.
*
* Create a new ClutterTextBuffer object with some text.
*
* Return value: A new ClutterTextBuffer object.
*
* Since: 1.10
**/
ClutterTextBuffer*
clutter_text_buffer_new_with_text (const gchar *text,
gssize text_len)
{
ClutterTextBuffer *buffer;
buffer = clutter_text_buffer_new ();
clutter_text_buffer_set_text (buffer, text, text_len);
return buffer;
}
/**
* clutter_text_buffer_get_length:
* @buffer: a #ClutterTextBuffer
*
* Retrieves the length in characters of the buffer.
*
* Return value: The number of characters in the buffer.
*
* Since: 1.10
**/
guint
clutter_text_buffer_get_length (ClutterTextBuffer *buffer)
{
ClutterTextBufferClass *klass;
g_return_val_if_fail (CLUTTER_IS_TEXT_BUFFER (buffer), 0);
klass = CLUTTER_TEXT_BUFFER_GET_CLASS (buffer);
g_return_val_if_fail (klass->get_length != NULL, 0);
return (*klass->get_length) (buffer);
}
/**
* clutter_text_buffer_get_bytes:
* @buffer: a #ClutterTextBuffer
*
* Retrieves the length in bytes of the buffer.
* See clutter_text_buffer_get_length().
*
* Return value: The byte length of the buffer.
*
* Since: 1.10
**/
gsize
clutter_text_buffer_get_bytes (ClutterTextBuffer *buffer)
{
ClutterTextBufferClass *klass;
gsize bytes = 0;
g_return_val_if_fail (CLUTTER_IS_TEXT_BUFFER (buffer), 0);
klass = CLUTTER_TEXT_BUFFER_GET_CLASS (buffer);
g_return_val_if_fail (klass->get_text != NULL, 0);
(*klass->get_text) (buffer, &bytes);
return bytes;
}
/**
* clutter_text_buffer_get_text:
* @buffer: a #ClutterTextBuffer
*
* Retrieves the contents of the buffer.
*
* The memory pointer returned by this call will not change
* unless this object emits a signal, or is finalized.
*
* Return value: a pointer to the contents of the widget as a
* string. This string points to internally allocated
* storage in the buffer and must not be freed, modified or
* stored.
*
* Since: 1.10
**/
const gchar*
clutter_text_buffer_get_text (ClutterTextBuffer *buffer)
{
ClutterTextBufferClass *klass;
g_return_val_if_fail (CLUTTER_IS_TEXT_BUFFER (buffer), NULL);
klass = CLUTTER_TEXT_BUFFER_GET_CLASS (buffer);
g_return_val_if_fail (klass->get_text != NULL, NULL);
return (*klass->get_text) (buffer, NULL);
}
/**
* clutter_text_buffer_set_text:
* @buffer: a #ClutterTextBuffer
* @chars: the new text
* @n_chars: the number of characters in @text, or -1
*
* Sets the text in the buffer.
*
* This is roughly equivalent to calling clutter_text_buffer_delete_text()
* and clutter_text_buffer_insert_text().
*
* Note that @n_chars is in characters, not in bytes.
*
* Since: 1.10
**/
void
clutter_text_buffer_set_text (ClutterTextBuffer *buffer,
const gchar *chars,
gint n_chars)
{
g_return_if_fail (CLUTTER_IS_TEXT_BUFFER (buffer));
g_return_if_fail (chars != NULL);
g_object_freeze_notify (G_OBJECT (buffer));
clutter_text_buffer_delete_text (buffer, 0, -1);
clutter_text_buffer_insert_text (buffer, 0, chars, n_chars);
g_object_thaw_notify (G_OBJECT (buffer));
}
/**
* clutter_text_buffer_set_max_length:
* @buffer: a #ClutterTextBuffer
* @max_length: the maximum length of the entry buffer, or 0 for no maximum.
* (other than the maximum length of entries.) The value passed in will
* be clamped to the range [ 0, %CLUTTER_TEXT_BUFFER_MAX_SIZE ].
*
* Sets the maximum allowed length of the contents of the buffer. If
* the current contents are longer than the given length, then they
* will be truncated to fit.
*
* Since: 1.10
**/
void
clutter_text_buffer_set_max_length (ClutterTextBuffer *buffer,
gint max_length)
{
g_return_if_fail (CLUTTER_IS_TEXT_BUFFER (buffer));
max_length = CLAMP (max_length, 0, CLUTTER_TEXT_BUFFER_MAX_SIZE);
if (max_length > 0 && clutter_text_buffer_get_length (buffer) > max_length)
clutter_text_buffer_delete_text (buffer, max_length, -1);
buffer->priv->max_length = max_length;
g_object_notify (G_OBJECT (buffer), "max-length");
}
/**
* clutter_text_buffer_get_max_length:
* @buffer: a #ClutterTextBuffer
*
* Retrieves the maximum allowed length of the text in
* @buffer. See clutter_text_buffer_set_max_length().
*
* Return value: the maximum allowed number of characters
* in #ClutterTextBuffer, or 0 if there is no maximum.
*
* Since: 1.10
*/
gint
clutter_text_buffer_get_max_length (ClutterTextBuffer *buffer)
{
g_return_val_if_fail (CLUTTER_IS_TEXT_BUFFER (buffer), 0);
return buffer->priv->max_length;
}
/**
* clutter_text_buffer_insert_text:
* @buffer: a #ClutterTextBuffer
* @position: the position at which to insert text.
* @chars: the text to insert into the buffer.
* @n_chars: the length of the text in characters, or -1
*
* Inserts @n_chars characters of @chars into the contents of the
* buffer, at position @position.
*
* If @n_chars is negative, then characters from chars will be inserted
* until a null-terminator is found. If @position or @n_chars are out of
* bounds, or the maximum buffer text length is exceeded, then they are
* coerced to sane values.
*
* Note that the position and length are in characters, not in bytes.
*
* Returns: The number of characters actually inserted.
*
* Since: 1.10
*/
guint
clutter_text_buffer_insert_text (ClutterTextBuffer *buffer,
guint position,
const gchar *chars,
gint n_chars)
{
ClutterTextBufferClass *klass;
ClutterTextBufferPrivate *pv;
guint length;
g_return_val_if_fail (CLUTTER_IS_TEXT_BUFFER (buffer), 0);
length = clutter_text_buffer_get_length (buffer);
pv = buffer->priv;
if (n_chars < 0)
n_chars = g_utf8_strlen (chars, -1);
/* Bring position into bounds */
if (position > length)
position = length;
/* Make sure not entering too much data */
if (pv->max_length > 0)
{
if (length >= pv->max_length)
n_chars = 0;
else if (length + n_chars > pv->max_length)
n_chars -= (length + n_chars) - pv->max_length;
}
klass = CLUTTER_TEXT_BUFFER_GET_CLASS (buffer);
g_return_val_if_fail (klass->insert_text != NULL, 0);
return (klass->insert_text) (buffer, position, chars, n_chars);
}
/**
* clutter_text_buffer_delete_text:
* @buffer: a #ClutterTextBuffer
* @position: position at which to delete text
* @n_chars: number of characters to delete
*
* Deletes a sequence of characters from the buffer. @n_chars characters are
* deleted starting at @position. If @n_chars is negative, then all characters
* until the end of the text are deleted.
*
* If @position or @n_chars are out of bounds, then they are coerced to sane
* values.
*
* Note that the positions are specified in characters, not bytes.
*
* Returns: The number of characters deleted.
*
* Since: 1.10
*/
guint
clutter_text_buffer_delete_text (ClutterTextBuffer *buffer,
guint position,
gint n_chars)
{
ClutterTextBufferClass *klass;
guint length;
g_return_val_if_fail (CLUTTER_IS_TEXT_BUFFER (buffer), 0);
length = clutter_text_buffer_get_length (buffer);
if (n_chars < 0)
n_chars = length;
if (position > length)
position = length;
if (position + n_chars > length)
n_chars = length - position;
klass = CLUTTER_TEXT_BUFFER_GET_CLASS (buffer);
g_return_val_if_fail (klass->delete_text != NULL, 0);
return (klass->delete_text) (buffer, position, n_chars);
}
/**
* clutter_text_buffer_emit_inserted_text:
* @buffer: a #ClutterTextBuffer
* @position: position at which text was inserted
* @chars: text that was inserted
* @n_chars: number of characters inserted
*
* Emits the #ClutterTextBuffer::inserted-text signal on @buffer.
*
* Used when subclassing #ClutterTextBuffer
*
* Since: 1.10
*/
void
clutter_text_buffer_emit_inserted_text (ClutterTextBuffer *buffer,
guint position,
const gchar *chars,
guint n_chars)
{
g_return_if_fail (CLUTTER_IS_TEXT_BUFFER (buffer));
g_signal_emit (buffer, signals[INSERTED_TEXT], 0, position, chars, n_chars);
}
/**
* clutter_text_buffer_emit_deleted_text:
* @buffer: a #ClutterTextBuffer
* @position: position at which text was deleted
* @n_chars: number of characters deleted
*
* Emits the #ClutterTextBuffer::deleted-text signal on @buffer.
*
* Used when subclassing #ClutterTextBuffer
*
* Since: 1.10
*/
void
clutter_text_buffer_emit_deleted_text (ClutterTextBuffer *buffer,
guint position,
guint n_chars)
{
g_return_if_fail (CLUTTER_IS_TEXT_BUFFER (buffer));
g_signal_emit (buffer, signals[DELETED_TEXT], 0, position, n_chars);
}