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-rw-r--r--src/libid3tag/field.c875
1 files changed, 875 insertions, 0 deletions
diff --git a/src/libid3tag/field.c b/src/libid3tag/field.c
new file mode 100644
index 000000000..a7b413edb
--- /dev/null
+++ b/src/libid3tag/field.c
@@ -0,0 +1,875 @@
+/*
+ * libid3tag - ID3 tag manipulation library
+ * Copyright (C) 2000-2003 Underbit Technologies, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * $Id: field.c,v 1.1 2003/08/14 03:57:13 shank Exp $
+ */
+
+# ifdef HAVE_CONFIG_H
+# include "config.h"
+# endif
+
+# include "global.h"
+
+# include <stdlib.h>
+# include <string.h>
+
+# ifdef HAVE_ASSERT_H
+# include <assert.h>
+# endif
+
+# include "id3tag.h"
+# include "field.h"
+# include "frame.h"
+# include "render.h"
+# include "ucs4.h"
+# include "latin1.h"
+# include "parse.h"
+
+/*
+ * NAME: field->init()
+ * DESCRIPTION: initialize a field to a default value for the given type
+ */
+void id3_field_init(union id3_field *field, enum id3_field_type type)
+{
+ assert(field);
+
+ switch (field->type = type) {
+ case ID3_FIELD_TYPE_TEXTENCODING:
+ case ID3_FIELD_TYPE_INT8:
+ case ID3_FIELD_TYPE_INT16:
+ case ID3_FIELD_TYPE_INT24:
+ case ID3_FIELD_TYPE_INT32:
+ field->number.value = 0;
+ break;
+
+ case ID3_FIELD_TYPE_LATIN1:
+ case ID3_FIELD_TYPE_LATIN1FULL:
+ field->latin1.ptr = 0;
+ break;
+
+ case ID3_FIELD_TYPE_LATIN1LIST:
+ field->latin1list.nstrings = 0;
+ field->latin1list.strings = 0;
+
+ case ID3_FIELD_TYPE_STRING:
+ case ID3_FIELD_TYPE_STRINGFULL:
+ field->string.ptr = 0;
+ break;
+
+ case ID3_FIELD_TYPE_STRINGLIST:
+ field->stringlist.nstrings = 0;
+ field->stringlist.strings = 0;
+ break;
+
+ case ID3_FIELD_TYPE_LANGUAGE:
+ strcpy(field->immediate.value, "XXX");
+ break;
+
+ case ID3_FIELD_TYPE_FRAMEID:
+ strcpy(field->immediate.value, "XXXX");
+ break;
+
+ case ID3_FIELD_TYPE_DATE:
+ memset(field->immediate.value, 0, sizeof(field->immediate.value));
+ break;
+
+ case ID3_FIELD_TYPE_INT32PLUS:
+ case ID3_FIELD_TYPE_BINARYDATA:
+ field->binary.data = 0;
+ field->binary.length = 0;
+ break;
+ }
+}
+
+/*
+ * NAME: field->finish()
+ * DESCRIPTION: reset a field, deallocating memory if necessary
+ */
+void id3_field_finish(union id3_field *field)
+{
+ unsigned int i;
+
+ assert(field);
+
+ switch (field->type) {
+ case ID3_FIELD_TYPE_TEXTENCODING:
+ case ID3_FIELD_TYPE_INT8:
+ case ID3_FIELD_TYPE_INT16:
+ case ID3_FIELD_TYPE_INT24:
+ case ID3_FIELD_TYPE_INT32:
+ case ID3_FIELD_TYPE_LANGUAGE:
+ case ID3_FIELD_TYPE_FRAMEID:
+ case ID3_FIELD_TYPE_DATE:
+ break;
+
+ case ID3_FIELD_TYPE_LATIN1:
+ case ID3_FIELD_TYPE_LATIN1FULL:
+ if (field->latin1.ptr)
+ free(field->latin1.ptr);
+ break;
+
+ case ID3_FIELD_TYPE_LATIN1LIST:
+ for (i = 0; i < field->latin1list.nstrings; ++i)
+ free(field->latin1list.strings[i]);
+
+ if (field->latin1list.strings)
+ free(field->latin1list.strings);
+ break;
+
+ case ID3_FIELD_TYPE_STRING:
+ case ID3_FIELD_TYPE_STRINGFULL:
+ if (field->string.ptr)
+ free(field->string.ptr);
+ break;
+
+ case ID3_FIELD_TYPE_STRINGLIST:
+ for (i = 0; i < field->stringlist.nstrings; ++i)
+ free(field->stringlist.strings[i]);
+
+ if (field->stringlist.strings)
+ free(field->stringlist.strings);
+ break;
+
+ case ID3_FIELD_TYPE_INT32PLUS:
+ case ID3_FIELD_TYPE_BINARYDATA:
+ if (field->binary.data)
+ free(field->binary.data);
+ break;
+ }
+
+ id3_field_init(field, field->type);
+}
+
+/*
+ * NAME: field->type()
+ * DESCRIPTION: return the value type of a field
+ */
+enum id3_field_type id3_field_type(union id3_field const *field)
+{
+ assert(field);
+
+ return field->type;
+}
+
+/*
+ * NAME: field->parse()
+ * DESCRIPTION: parse a field value
+ */
+int id3_field_parse(union id3_field *field, id3_byte_t const **ptr,
+ id3_length_t length, enum id3_field_textencoding *encoding)
+{
+ assert(field);
+
+ id3_field_finish(field);
+
+ switch (field->type) {
+ case ID3_FIELD_TYPE_INT32:
+ if (length < 4)
+ goto fail;
+
+ field->number.value = id3_parse_uint(ptr, 4);
+ break;
+
+ case ID3_FIELD_TYPE_INT24:
+ if (length < 3)
+ goto fail;
+
+ field->number.value = id3_parse_uint(ptr, 3);
+ break;
+
+ case ID3_FIELD_TYPE_INT16:
+ if (length < 2)
+ goto fail;
+
+ field->number.value = id3_parse_uint(ptr, 2);
+ break;
+
+ case ID3_FIELD_TYPE_INT8:
+ case ID3_FIELD_TYPE_TEXTENCODING:
+ if (length < 1)
+ goto fail;
+
+ field->number.value = id3_parse_uint(ptr, 1);
+
+ if (field->type == ID3_FIELD_TYPE_TEXTENCODING)
+ *encoding = field->number.value;
+ break;
+
+ case ID3_FIELD_TYPE_LANGUAGE:
+ if (length < 3)
+ goto fail;
+
+ id3_parse_immediate(ptr, 3, field->immediate.value);
+ break;
+
+ case ID3_FIELD_TYPE_FRAMEID:
+ if (length < 4)
+ goto fail;
+
+ id3_parse_immediate(ptr, 4, field->immediate.value);
+ break;
+
+ case ID3_FIELD_TYPE_DATE:
+ if (length < 8)
+ goto fail;
+
+ id3_parse_immediate(ptr, 8, field->immediate.value);
+ break;
+
+ case ID3_FIELD_TYPE_LATIN1:
+ case ID3_FIELD_TYPE_LATIN1FULL:
+ {
+ id3_latin1_t *latin1;
+
+ latin1 = id3_parse_latin1(ptr, length,
+ field->type == ID3_FIELD_TYPE_LATIN1FULL);
+ if (latin1 == 0)
+ goto fail;
+
+ field->latin1.ptr = latin1;
+ }
+ break;
+
+ case ID3_FIELD_TYPE_LATIN1LIST:
+ {
+ id3_byte_t const *end;
+ id3_latin1_t *latin1, **strings;
+
+ end = *ptr + length;
+
+ while (end - *ptr > 0) {
+ latin1 = id3_parse_latin1(ptr, end - *ptr, 0);
+ if (latin1 == 0)
+ goto fail;
+
+ strings = realloc(field->latin1list.strings,
+ (field->latin1list.nstrings + 1) * sizeof(*strings));
+ if (strings == 0) {
+ free(latin1);
+ goto fail;
+ }
+
+ field->latin1list.strings = strings;
+ field->latin1list.strings[field->latin1list.nstrings++] = latin1;
+ }
+ }
+ break;
+
+ case ID3_FIELD_TYPE_STRING:
+ case ID3_FIELD_TYPE_STRINGFULL:
+ {
+ id3_ucs4_t *ucs4;
+
+ ucs4 = id3_parse_string(ptr, length, *encoding,
+ field->type == ID3_FIELD_TYPE_STRINGFULL);
+ if (ucs4 == 0)
+ goto fail;
+
+ field->string.ptr = ucs4;
+ }
+ break;
+
+ case ID3_FIELD_TYPE_STRINGLIST:
+ {
+ id3_byte_t const *end;
+ id3_ucs4_t *ucs4, **strings;
+
+ end = *ptr + length;
+
+ while (end - *ptr > 0) {
+ ucs4 = id3_parse_string(ptr, end - *ptr, *encoding, 0);
+ if (ucs4 == 0)
+ goto fail;
+
+ strings = realloc(field->stringlist.strings,
+ (field->stringlist.nstrings + 1) * sizeof(*strings));
+ if (strings == 0) {
+ free(ucs4);
+ goto fail;
+ }
+
+ field->stringlist.strings = strings;
+ field->stringlist.strings[field->stringlist.nstrings++] = ucs4;
+ }
+ }
+ break;
+
+ case ID3_FIELD_TYPE_INT32PLUS:
+ case ID3_FIELD_TYPE_BINARYDATA:
+ {
+ id3_byte_t *data;
+
+ data = id3_parse_binary(ptr, length);
+ if (data == 0)
+ goto fail;
+
+ field->binary.data = data;
+ field->binary.length = length;
+ }
+ break;
+ }
+
+ return 0;
+
+ fail:
+ return -1;
+}
+
+/*
+ * NAME: field->render()
+ * DESCRIPTION: render a field value
+ */
+id3_length_t id3_field_render(union id3_field const *field, id3_byte_t **ptr,
+ enum id3_field_textencoding *encoding,
+ int terminate)
+{
+ id3_length_t size;
+ unsigned int i;
+
+ assert(field && encoding);
+
+ switch (field->type) {
+ case ID3_FIELD_TYPE_INT32:
+ return id3_render_int(ptr, field->number.value, 4);
+
+ case ID3_FIELD_TYPE_INT24:
+ return id3_render_int(ptr, field->number.value, 3);
+
+ case ID3_FIELD_TYPE_INT16:
+ return id3_render_int(ptr, field->number.value, 2);
+
+ case ID3_FIELD_TYPE_TEXTENCODING:
+ *encoding = field->number.value;
+ case ID3_FIELD_TYPE_INT8:
+ return id3_render_int(ptr, field->number.value, 1);
+
+ case ID3_FIELD_TYPE_LATIN1:
+ case ID3_FIELD_TYPE_LATIN1FULL:
+ return id3_render_latin1(ptr, field->latin1.ptr, terminate);
+
+ case ID3_FIELD_TYPE_LATIN1LIST:
+ size = 0;
+ for (i = 0; i < field->latin1list.nstrings; ++i) {
+ size += id3_render_latin1(ptr, field->latin1list.strings[i],
+ (i < field->latin1list.nstrings - 1) ||
+ terminate);
+ }
+ return size;
+
+ case ID3_FIELD_TYPE_STRING:
+ case ID3_FIELD_TYPE_STRINGFULL:
+ return id3_render_string(ptr, field->string.ptr, *encoding, terminate);
+
+ case ID3_FIELD_TYPE_STRINGLIST:
+ size = 0;
+ for (i = 0; i < field->stringlist.nstrings; ++i) {
+ size += id3_render_string(ptr, field->stringlist.strings[i], *encoding,
+ (i < field->stringlist.nstrings - 1) ||
+ terminate);
+ }
+ return size;
+
+ case ID3_FIELD_TYPE_LANGUAGE:
+ return id3_render_immediate(ptr, field->immediate.value, 3);
+
+ case ID3_FIELD_TYPE_FRAMEID:
+ return id3_render_immediate(ptr, field->immediate.value, 4);
+
+ case ID3_FIELD_TYPE_DATE:
+ return id3_render_immediate(ptr, field->immediate.value, 8);
+
+ case ID3_FIELD_TYPE_INT32PLUS:
+ case ID3_FIELD_TYPE_BINARYDATA:
+ return id3_render_binary(ptr, field->binary.data, field->binary.length);
+ }
+
+ return 0;
+}
+
+/*
+ * NAME: field->setint()
+ * DESCRIPTION: set the value of an int field
+ */
+int id3_field_setint(union id3_field *field, signed long number)
+{
+ assert(field);
+
+ switch (field->type) {
+ case ID3_FIELD_TYPE_INT8:
+ if (number > 0x7f || number < -0x80)
+ return -1;
+ break;
+
+ case ID3_FIELD_TYPE_INT16:
+ if (number > 0x7fff || number < -0x8000)
+ return -1;
+ break;
+
+ case ID3_FIELD_TYPE_INT24:
+ if (number > 0x7fffffL || number < -0x800000L)
+ return -1;
+ break;
+
+ case ID3_FIELD_TYPE_INT32:
+ if (number > 0x7fffffffL || number < -0x80000000L)
+ return -1;
+ break;
+
+ default:
+ return -1;
+ }
+
+ id3_field_finish(field);
+
+ field->number.value = number;
+
+ return 0;
+}
+
+/*
+ * NAME: field->settextencoding()
+ * DESCRIPTION: set the value of a textencoding field
+ */
+int id3_field_settextencoding(union id3_field *field,
+ enum id3_field_textencoding encoding)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_TEXTENCODING)
+ return -1;
+
+ id3_field_finish(field);
+
+ field->number.value = encoding;
+
+ return 0;
+}
+
+static
+int set_latin1(union id3_field *field, id3_latin1_t const *latin1)
+{
+ id3_latin1_t *data;
+
+ if (latin1 == 0 || *latin1 == 0)
+ data = 0;
+ else {
+ data = id3_latin1_duplicate(latin1);
+ if (data == 0)
+ return -1;
+ }
+
+ field->latin1.ptr = data;
+
+ return 0;
+}
+
+/*
+ * NAME: field->setlatin1()
+ * DESCRIPTION: set the value of a latin1 field
+ */
+int id3_field_setlatin1(union id3_field *field, id3_latin1_t const *latin1)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_LATIN1)
+ return -1;
+
+ id3_field_finish(field);
+
+ if (latin1) {
+ id3_latin1_t const *ptr;
+
+ for (ptr = latin1; *ptr; ++ptr) {
+ if (*ptr == '\n')
+ return -1;
+ }
+ }
+
+ return set_latin1(field, latin1);
+}
+
+/*
+ * NAME: field->setfulllatin1()
+ * DESCRIPTION: set the value of a full latin1 field
+ */
+int id3_field_setfulllatin1(union id3_field *field, id3_latin1_t const *latin1)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_LATIN1FULL)
+ return -1;
+
+ id3_field_finish(field);
+
+ return set_latin1(field, latin1);
+}
+
+static
+int set_string(union id3_field *field, id3_ucs4_t const *string)
+{
+ id3_ucs4_t *data;
+
+ if (string == 0 || *string == 0)
+ data = 0;
+ else {
+ data = id3_ucs4_duplicate(string);
+ if (data == 0)
+ return -1;
+ }
+
+ field->string.ptr = data;
+
+ return 0;
+}
+
+/*
+ * NAME: field->setstring()
+ * DESCRIPTION: set the value of a string field
+ */
+int id3_field_setstring(union id3_field *field, id3_ucs4_t const *string)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_STRING)
+ return -1;
+
+ id3_field_finish(field);
+
+ if (string) {
+ id3_ucs4_t const *ptr;
+
+ for (ptr = string; *ptr; ++ptr) {
+ if (*ptr == '\n')
+ return -1;
+ }
+ }
+
+ return set_string(field, string);
+}
+
+/*
+ * NAME: field->setfullstring()
+ * DESCRIPTION: set the value of a full string field
+ */
+int id3_field_setfullstring(union id3_field *field, id3_ucs4_t const *string)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_STRINGFULL)
+ return -1;
+
+ id3_field_finish(field);
+
+ return set_string(field, string);
+}
+
+/*
+ * NAME: field->setstrings()
+ * DESCRIPTION: set the value of a stringlist field
+ */
+int id3_field_setstrings(union id3_field *field,
+ unsigned int length, id3_ucs4_t **ptrs)
+{
+ id3_ucs4_t **strings;
+ unsigned int i;
+
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_STRINGLIST)
+ return -1;
+
+ id3_field_finish(field);
+
+ if (length == 0)
+ return 0;
+
+ strings = malloc(length * sizeof(*strings));
+ if (strings == 0)
+ return -1;
+
+ for (i = 0; i < length; ++i) {
+ strings[i] = id3_ucs4_duplicate(ptrs[i]);
+ if (strings[i] == 0) {
+ while (i--)
+ free(strings[i]);
+
+ free(strings);
+ return -1;
+ }
+ }
+
+ field->stringlist.strings = strings;
+ field->stringlist.nstrings = length;
+
+ return 0;
+}
+
+/*
+ * NAME: field->addstring()
+ * DESCRIPTION: add a string to a stringlist field
+ */
+int id3_field_addstring(union id3_field *field, id3_ucs4_t const *string)
+{
+ id3_ucs4_t *new, **strings;
+
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_STRINGLIST)
+ return -1;
+
+ if (string == 0)
+ string = id3_ucs4_empty;
+
+ new = id3_ucs4_duplicate(string);
+ if (new == 0)
+ return -1;
+
+ strings = realloc(field->stringlist.strings,
+ (field->stringlist.nstrings + 1) * sizeof(*strings));
+ if (strings == 0) {
+ free(new);
+ return -1;
+ }
+
+ field->stringlist.strings = strings;
+ field->stringlist.strings[field->stringlist.nstrings++] = new;
+
+ return 0;
+}
+
+/*
+ * NAME: field->setlanguage()
+ * DESCRIPTION: set the value of a language field
+ */
+int id3_field_setlanguage(union id3_field *field, char const *language)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_LANGUAGE)
+ return -1;
+
+ id3_field_finish(field);
+
+ if (language) {
+ if (strlen(language) != 3)
+ return -1;
+
+ strcpy(field->immediate.value, language);
+ }
+
+ return 0;
+}
+
+/*
+ * NAME: field->setframeid()
+ * DESCRIPTION: set the value of a frameid field
+ */
+int id3_field_setframeid(union id3_field *field, char const *id)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_FRAMEID ||
+ !id3_frame_validid(id))
+ return -1;
+
+ id3_field_finish(field);
+
+ field->immediate.value[0] = id[0];
+ field->immediate.value[1] = id[1];
+ field->immediate.value[2] = id[2];
+ field->immediate.value[3] = id[3];
+ field->immediate.value[4] = 0;
+
+ return 0;
+}
+
+/*
+ * NAME: field->setbinarydata()
+ * DESCRIPTION: set the value of a binarydata field
+ */
+int id3_field_setbinarydata(union id3_field *field,
+ id3_byte_t const *data, id3_length_t length)
+{
+ id3_byte_t *mem;
+
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_BINARYDATA)
+ return -1;
+
+ id3_field_finish(field);
+
+ if (length == 0)
+ mem = 0;
+ else {
+ mem = malloc(length);
+ if (mem == 0)
+ return -1;
+
+ assert(data);
+
+ memcpy(mem, data, length);
+ }
+
+ field->binary.data = mem;
+ field->binary.length = length;
+
+ return 0;
+}
+
+/*
+ * NAME: field->getint()
+ * DESCRIPTION: return the value of an integer field
+ */
+signed long id3_field_getint(union id3_field const *field)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_INT8 &&
+ field->type != ID3_FIELD_TYPE_INT16 &&
+ field->type != ID3_FIELD_TYPE_INT24 &&
+ field->type != ID3_FIELD_TYPE_INT32)
+ return -1;
+
+ return field->number.value;
+}
+
+/*
+ * NAME: field->getlatin1()
+ * DESCRIPTION: return the value of a latin1 field
+ */
+id3_latin1_t const *id3_field_getlatin1(union id3_field const *field)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_LATIN1)
+ return 0;
+
+ return field->latin1.ptr ? field->latin1.ptr : (id3_latin1_t const *) "";
+}
+
+/*
+ * NAME: field->getfulllatin1()
+ * DESCRIPTION: return the value of a full latin1 field
+ */
+id3_latin1_t const *id3_field_getfulllatin1(union id3_field const *field)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_LATIN1FULL)
+ return 0;
+
+ return field->latin1.ptr ? field->latin1.ptr : (id3_latin1_t const *) "";
+}
+
+/*
+ * NAME: field->getstring()
+ * DESCRIPTION: return the value of a string field
+ */
+id3_ucs4_t const *id3_field_getstring(union id3_field const *field)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_STRING)
+ return 0;
+
+ return field->string.ptr ? field->string.ptr : id3_ucs4_empty;
+}
+
+/*
+ * NAME: field->getfullstring()
+ * DESCRIPTION: return the value of a fullstring field
+ */
+id3_ucs4_t const *id3_field_getfullstring(union id3_field const *field)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_STRINGFULL)
+ return 0;
+
+ return field->string.ptr ? field->string.ptr : id3_ucs4_empty;
+}
+
+/*
+ * NAME: field->getnstrings()
+ * DESCRIPTION: return the number of strings in a stringlist field
+ */
+unsigned int id3_field_getnstrings(union id3_field const *field)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_STRINGLIST)
+ return 0;
+
+ return field->stringlist.nstrings;
+}
+
+/*
+ * NAME: field->getstrings()
+ * DESCRIPTION: return one value of a stringlist field
+ */
+id3_ucs4_t const *id3_field_getstrings(union id3_field const *field,
+ unsigned int index)
+{
+ id3_ucs4_t const *string;
+
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_STRINGLIST ||
+ index >= field->stringlist.nstrings)
+ return 0;
+
+ string = field->stringlist.strings[index];
+
+ return string ? string : id3_ucs4_empty;
+}
+
+/*
+ * NAME: field->getframeid()
+ * DESCRIPTION: return the value of a frameid field
+ */
+char const *id3_field_getframeid(union id3_field const *field)
+{
+ assert(field);
+
+ if (field->type != ID3_FIELD_TYPE_FRAMEID)
+ return 0;
+
+ return field->immediate.value;
+}
+
+/*
+ * NAME: field->getbinarydata()
+ * DESCRIPTION: return the value of a binarydata field
+ */
+id3_byte_t const *id3_field_getbinarydata(union id3_field const *field,
+ id3_length_t *length)
+{
+ static id3_byte_t const empty;
+
+ assert(field && length);
+
+ if (field->type != ID3_FIELD_TYPE_BINARYDATA)
+ return 0;
+
+ assert(field->binary.length == 0 || field->binary.data);
+
+ *length = field->binary.length;
+
+ return field->binary.data ? field->binary.data : &empty;
+}