path: root/libempathy-gtk/empathy-plist.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 * Copyright (C) 2008 Christophe Fergeau <teuf@gnome.org>
 * Based on itdb_plist parser from the gtkpod project.
 *
 * The code contained in this file is free software; you can redistribute
 * it and/or modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either version
 * 2.1 of the License, or (at your option) any later version.
 *
 * This file 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this code; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02111-1307  USA
 */

#include "config.h"

#include <string.h>
#include <libxml/parser.h>
#include <libxml/tree.h>
#include <glib.h>
#include <glib-object.h>

#include "empathy-plist.h"

static GValue *empathy_plist_parse_node (xmlNode *a_node);

static void
empathy_plist_value_free (GValue *val)
{
    g_value_unset (val);
    g_free (val);
}

static GValue *
empathy_plist_parse_integer (xmlNode *a_node)
{
    char *str_val;
    char *end_ptr;
    gint int_val;
    GValue *value;

    str_val = (char *) xmlNodeGetContent (a_node);
    int_val = strtol (str_val, &end_ptr, 0);
    if (*end_ptr != '\0') {
        xmlFree (str_val);
        return NULL;
    }
    xmlFree (str_val);

    value = g_new0(GValue, 1);
    g_value_init(value, G_TYPE_INT);
    g_value_set_int (value, int_val);

    return value;
}

static GValue *
empathy_plist_parse_string (xmlNode *a_node)
{
    char *str_val;
    GValue *value;

    str_val = (char *) xmlNodeGetContent (a_node);

    value = g_new0 (GValue, 1);
    g_value_init (value, G_TYPE_STRING);
    g_value_set_string (value, str_val);

    xmlFree (str_val);

    return value;
}

static GValue *
empathy_plist_parse_real (xmlNode *a_node)
{
    char *str_val;
    char *end_ptr;
    gfloat double_val;
    GValue *value;

    str_val = (char *) xmlNodeGetContent (a_node);
    double_val = g_ascii_strtod (str_val, &end_ptr);
    if (*end_ptr != '\0') {
        xmlFree (str_val);
        return NULL;
    }
    xmlFree (str_val);

    value = g_new0 (GValue, 1);
    g_value_init (value, G_TYPE_DOUBLE);
    g_value_set_double (value, double_val);

    return value;
}

static GValue *
empathy_plist_parse_boolean (xmlNode *a_node)
{
    gboolean bool_val;
    GValue *value;

    if (strcmp ((char *) a_node->name, "true") == 0) {
        bool_val = TRUE;
    } else if (strcmp ((char *) a_node->name, "false") == 0) {
        bool_val = FALSE;
    } else {
        return NULL;
    }

    value = g_new0 (GValue, 1);
    g_value_init (value, G_TYPE_BOOLEAN);
    g_value_set_boolean (value, bool_val);

    return value;
}

static GValue *
empathy_plist_parse_data (xmlNode *a_node)
{
    char *str_val;
    guchar *raw_data;
    gsize len;
    GString *data_val;
    GValue *value;

    str_val = (char *) xmlNodeGetContent (a_node);
    raw_data = g_base64_decode (str_val, &len);
    xmlFree (str_val);
    data_val = g_string_new_len ((char *) raw_data, len);
    g_free (raw_data);

    value = g_new0 (GValue, 1);
    g_value_init(value, G_TYPE_GSTRING);
    g_value_take_boxed (value, data_val);

    return value;
}

static xmlNode *
empathy_plist_parse_one_dict_entry (xmlNode *a_node, GHashTable *dict)
{
    xmlNode *cur_node = a_node;
    xmlChar *key_name;
    GValue *value;

    while (cur_node &&
           (xmlStrcmp(cur_node->name, (xmlChar *) "key") != 0)) {
        cur_node = cur_node->next;
    }
    if (!cur_node) {
        return NULL;
    }
    key_name = xmlNodeGetContent (cur_node);
    cur_node = cur_node->next;
    while (cur_node && xmlIsBlankNode (cur_node)) {
        cur_node = cur_node->next;
    }
    if (!cur_node) {
        xmlFree (key_name);
        return NULL;
    }

    value = empathy_plist_parse_node (cur_node);
    if (value) {
        g_hash_table_insert (dict, g_strdup ((char *) key_name), value);
    }
    xmlFree (key_name);

    return cur_node->next;
}

static GValue *
empathy_plist_parse_dict (xmlNode *a_node)
{
    xmlNode *cur_node = a_node->children;
    GValue *value;
    GHashTable *dict;

    dict = g_hash_table_new_full (g_str_hash, g_str_equal,
                                  g_free, (GDestroyNotify) empathy_plist_value_free);

    while (cur_node) {
        if (xmlIsBlankNode (cur_node)) {
            cur_node = cur_node->next;
        } else {
            cur_node = empathy_plist_parse_one_dict_entry (cur_node, dict);
        }
    }
    value = g_new0 (GValue, 1);
    value = g_value_init (value, G_TYPE_HASH_TABLE);
    g_value_take_boxed (value, dict);

    return value;
}

typedef GValue *(*ParseCallback) (xmlNode *);

static ParseCallback empathy_plist_get_parser_for_type (const xmlChar *type);

static GValue *
empathy_plist_parse_array (xmlNode *a_node)
{
    xmlNode *cur_node = a_node->children;
    GValue *value;
    GValueArray *array;

    array = g_value_array_new (4);

    while (cur_node) {
        if (empathy_plist_get_parser_for_type (cur_node->name)) {
            GValue *cur_value;
            cur_value = empathy_plist_parse_node (cur_node);
            if (cur_value) {
                array = g_value_array_append (array, cur_value);
                g_value_unset (cur_value);
                g_free (cur_value);
            }
        }
        /* When an array contains an element enclosed in "unknown" tags (ie
         * non-type ones), we silently skip them since early
         * SysInfoExtended files used to have <key> values enclosed within
         * <array> tags.
         */
        cur_node = cur_node->next;
    }

    value = g_new0 (GValue, 1);
    value = g_value_init (value, G_TYPE_VALUE_ARRAY);
    g_value_take_boxed (value, array);

    return value;
}

struct Parser {
    const char * const type_name;
    ParseCallback parser;
};

static const struct Parser parsers[] = { {"integer", empathy_plist_parse_integer},
                     {"real",    empathy_plist_parse_real},
                     {"string",  empathy_plist_parse_string},
                     {"true",    empathy_plist_parse_boolean},
                     {"false",   empathy_plist_parse_boolean},
                     {"data",    empathy_plist_parse_data},
                     {"dict",    empathy_plist_parse_dict},
                     {"array",   empathy_plist_parse_array},
                     {NULL,   NULL} };

static ParseCallback
empathy_plist_get_parser_for_type (const xmlChar *type)
{
    guint i = 0;

    while (parsers[i].type_name) {
        if (xmlStrcmp (type, (xmlChar *) parsers[i].type_name) == 0) {
            if (parsers[i].parser) {
                return parsers[i].parser;
            }
        }
        i++;
    }
    return NULL;
}

static GValue *
empathy_plist_parse_node (xmlNode *a_node)
{
    ParseCallback parser;

    g_return_val_if_fail (a_node != NULL, NULL);
    parser = empathy_plist_get_parser_for_type (a_node->name);
    if (parser) {
        return parser (a_node);
    } else {
        return NULL;
    }
}

static GValue *
empathy_plist_parse (xmlNode * a_node)
{
    xmlNode *cur_node;
    if (!a_node) {
        return NULL;
    }
    if (xmlStrcmp (a_node->name, (xmlChar *) "plist") != 0) {
        return NULL;
    }
    cur_node = a_node->xmlChildrenNode;
    while (cur_node && (xmlIsBlankNode (cur_node))) {
        cur_node = cur_node->next;
    }
    if (cur_node) {
        return empathy_plist_parse_node (cur_node);
    }
    return NULL;
}

GValue *
empathy_plist_parse_from_file (const char *filename)
{
    xmlDoc *doc = NULL;
    xmlNode *root_element = NULL;
    GValue *parsed_doc;

    doc = xmlReadFile (filename, NULL, 0);

    if (!doc) {
        return NULL;
    }

    root_element = xmlDocGetRootElement (doc);

    parsed_doc = empathy_plist_parse (root_element);

    xmlFreeDoc(doc);
    xmlCleanupParser();

    return parsed_doc;
}

/**
 * empathy_plist_parse_from_memory:
 * @data:   memory location containing XML plist data to parse
 * @len:    length in bytes of the string to parse
 *
 * Parses the XML plist file stored in @data which length is @len
 * bytes. If an error occurs during the parsing,
 * empathy_plist_parse_from_memory() will return NULL.
 *
 * Returns: NULL on error, a newly allocated
 * #GValue containing a #GHashTable otherwise.
 */
GValue *
empathy_plist_parse_from_memory (const char *data, gsize len)
{
    xmlDoc *doc = NULL;
    xmlNode *root_element = NULL;
    GValue *parsed_doc;

    doc = xmlReadMemory (data, len, "noname.xml", NULL, 0);

    if (doc == NULL) {
        return NULL;
    }

    root_element = xmlDocGetRootElement (doc);

    parsed_doc = empathy_plist_parse (root_element);

    xmlFreeDoc(doc);
    xmlCleanupParser();

    return parsed_doc;
}

gboolean
empathy_plist_get_int (GValue *data, const gchar *key, gint *value)
{
    GHashTable *hash;
    GValue     *entry;

    if (!data || !G_VALUE_HOLDS (data, G_TYPE_HASH_TABLE)) {
        return FALSE;
    }

    hash = g_value_get_boxed (data);
    entry = g_hash_table_lookup (hash, key);

    if (!entry || !G_VALUE_HOLDS (entry, G_TYPE_INT)) {
        return FALSE;
    }

    *value = g_value_get_int (entry);
    return TRUE;
}

gboolean
empathy_plist_get_string (GValue *data, const gchar *key, gchar **value)
{
    GHashTable *hash;
    GValue     *entry;

    if (!data || !G_VALUE_HOLDS (data, G_TYPE_HASH_TABLE)) {
        return FALSE;
    }

    hash = g_value_get_boxed (data);
    entry = g_hash_table_lookup (hash, key);

    if (!entry || !G_VALUE_HOLDS (entry, G_TYPE_STRING)) {
        return FALSE;
    }

    *value = g_value_dup_string (entry);
    return TRUE;
}