Moved xmltree to lib/ because I want to use it from more than just the

Jabber module.

1 files changed, 589 insertions, 0 deletions

diff --git a/lib/xmltree.c b/lib/xmltree.c
new file mode 100644
index 00000000..62549eb5
--- /dev/null
+++ b/lib/xmltree.c
@@ -0,0 +1,589 @@
+/***************************************************************************\
+*                                                                           *
+*  BitlBee - An IRC to IM gateway                                           *
+*  Simple XML (stream) parse tree handling code (Jabber/XMPP, mainly)       *
+*                                                                           *
+*  Copyright 2006 Wilmer van der Gaast <wilmer@gaast.net>                   *
+*                                                                           *
+*  This library 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, version            *
+*  2.1.                                                                     *
+*                                                                           *
+*  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        *
+*  Lesser General Public License for more details.                          *
+*                                                                           *
+*  You should have received a copy of the GNU Lesser 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           *
+*                                                                           *
+****************************************************************************/
+
+#include <glib.h>
+#include <string.h>
+#include <unistd.h>
+#include <ctype.h>
+#include <stdio.h>
+
+#include "xmltree.h"
+
+static void xt_start_element( GMarkupParseContext *ctx, const gchar *element_name, const gchar **attr_names, const gchar **attr_values, gpointer data, GError **error )
+{
+	struct xt_parser *xt = data;
+	struct xt_node *node = g_new0( struct xt_node, 1 ), *nt;
+	int i;
+	
+	node->parent = xt->cur;
+	node->name = g_strdup( element_name );
+	
+	/* First count the number of attributes */
+	for( i = 0; attr_names[i]; i ++ );
+	
+	/* Then allocate a NULL-terminated array. */
+	node->attr = g_new0( struct xt_attr, i + 1 );
+	
+	/* And fill it, saving one variable by starting at the end. */
+	for( i --; i >= 0; i -- )
+	{
+		node->attr[i].key = g_strdup( attr_names[i] );
+		node->attr[i].value = g_strdup( attr_values[i] );
+	}
+	
+	/* Add it to the linked list of children nodes, if we have a current
+	   node yet. */
+	if( xt->cur )
+	{
+		if( xt->cur->children )
+		{
+			for( nt = xt->cur->children; nt->next; nt = nt->next );
+			nt->next = node;
+		}
+		else
+		{
+			xt->cur->children = node;
+		}
+	}
+	else if( xt->root )
+	{
+		/* ERROR situation: A second root-element??? */
+	}
+	
+	/* Now this node will be the new current node. */
+	xt->cur = node;
+	/* And maybe this is the root? */
+	if( xt->root == NULL )
+		xt->root = node;
+}
+
+static void xt_text( GMarkupParseContext *ctx, const gchar *text, gsize text_len, gpointer data, GError **error )
+{
+	struct xt_parser *xt = data;
+	struct xt_node *node = xt->cur;
+	
+	if( node == NULL )
+		return;
+	
+	/* FIXME: Does g_renew also OFFICIALLY accept NULL arguments? */
+	node->text = g_renew( char, node->text, node->text_len + text_len + 1 );
+	memcpy( node->text + node->text_len, text, text_len );
+	node->text_len += text_len;
+	/* Zero termination is always nice to have. */
+	node->text[node->text_len] = 0;
+}
+
+static void xt_end_element( GMarkupParseContext *ctx, const gchar *element_name, gpointer data, GError **error )
+{
+	struct xt_parser *xt = data;
+	
+	xt->cur->flags |= XT_COMPLETE;
+	xt->cur = xt->cur->parent;
+}
+
+GMarkupParser xt_parser_funcs =
+{
+	xt_start_element,
+	xt_end_element,
+	xt_text,
+	NULL,
+	NULL
+};
+
+struct xt_parser *xt_new( gpointer data )
+{
+	struct xt_parser *xt = g_new0( struct xt_parser, 1 );
+	
+	xt->data = data;
+	xt_reset( xt );
+	
+	return xt;
+}
+
+/* Reset the parser, flush everything we have so far. For example, we need
+   this for XMPP when doing TLS/SASL to restart the stream. */
+void xt_reset( struct xt_parser *xt )
+{
+	if( xt->parser )
+		g_markup_parse_context_free( xt->parser );
+	
+	xt->parser = g_markup_parse_context_new( &xt_parser_funcs, 0, xt, NULL );
+	
+	if( xt->root )
+	{
+		xt_free_node( xt->root );
+		xt->root = NULL;
+		xt->cur = NULL;
+	}
+}
+
+/* Feed the parser, don't execute any handler. Returns -1 on errors, 0 on
+   end-of-stream and 1 otherwise. */
+int xt_feed( struct xt_parser *xt, char *text, int text_len )
+{
+	if( !g_markup_parse_context_parse( xt->parser, text, text_len, &xt->gerr ) )
+	{
+		return -1;
+	}
+	
+	return !( xt->root && xt->root->flags & XT_COMPLETE );
+}
+
+/* Find completed nodes and see if a handler has to be called. Passing
+   a node isn't necessary if you want to start at the root, just pass
+   NULL. This second argument is needed for recursive calls. */
+int xt_handle( struct xt_parser *xt, struct xt_node *node, int depth )
+{
+	struct xt_node *c;
+	xt_status st;
+	int i;
+	
+	/* Just in case someone likes infinite loops... */
+	if( xt->root == NULL )
+		return 0;
+	
+	if( node == NULL )
+		return xt_handle( xt, xt->root, depth );
+	
+	if( depth != 0 )
+		for( c = node->children; c; c = c->next )
+			if( !xt_handle( xt, c, depth > 0 ? depth - 1 : depth ) )
+				return 0;
+	
+	if( node->flags & XT_COMPLETE && !( node->flags & XT_SEEN ) )
+	{
+		for( i = 0; xt->handlers[i].func; i ++ )
+		{
+			/* This one is fun! \o/ */
+			
+						/* If handler.name == NULL it means it should always match. */
+			if( ( xt->handlers[i].name == NULL || 
+						/* If it's not, compare. There should always be a name. */
+			      g_strcasecmp( xt->handlers[i].name, node->name ) == 0 ) &&
+						/* If handler.parent == NULL, it's a match. */
+			    ( xt->handlers[i].parent == NULL ||
+						/* If there's a parent node, see if the name matches. */
+			      ( node->parent ? g_strcasecmp( xt->handlers[i].parent, node->parent->name ) == 0 : 
+						/* If there's no parent, the handler should mention <root> as a parent. */
+			                       g_strcasecmp( xt->handlers[i].parent, "<root>" ) == 0 ) ) )
+			{
+				st = xt->handlers[i].func( node, xt->data );
+				
+				if( st == XT_ABORT )
+					return 0;
+				else if( st != XT_NEXT )
+					break;
+			}
+		}
+		
+		node->flags |= XT_SEEN;
+	}
+	
+	return 1;
+}
+
+/* Garbage collection: Cleans up all nodes that are handled. Useful for
+   streams because there's no reason to keep a complete packet history
+   in memory. */
+void xt_cleanup( struct xt_parser *xt, struct xt_node *node, int depth )
+{
+	struct xt_node *c, *prev;
+	
+	if( !xt || !xt->root )
+		return;
+	
+	if( node == NULL )
+		return xt_cleanup( xt, xt->root, depth );
+	
+	if( node->flags & XT_SEEN && node == xt->root )
+	{
+		xt_free_node( xt->root );
+		xt->root = xt->cur = NULL;
+		/* xt->cur should be NULL already, BTW... */
+		
+		return;
+	}
+	
+	/* c contains the current node, prev the previous node (or NULL).
+	   I admit, this one's pretty horrible. */
+	for( c = node->children, prev = NULL; c; prev = c, c = c ? c->next : node->children )
+	{
+		if( c->flags & XT_SEEN )
+		{
+			/* Remove the node from the linked list. */
+			if( prev )
+				prev->next = c->next;
+			else
+				node->children = c->next;
+			
+			xt_free_node( c );
+			
+			/* Since the for loop wants to get c->next, make sure
+			   c points at something that exists (and that c->next
+			   will actually be the next item we should check). c
+			   can be NULL now, if we just removed the first item.
+			   That explains the ? thing in for(). */
+			c = prev;
+		}
+		else
+		{
+			/* This node can't be cleaned up yet, but maybe a
+			   subnode can. */
+			if( depth != 0 )
+				xt_cleanup( xt, c, depth > 0 ? depth - 1 : depth );
+		}
+	}
+}
+
+static void xt_to_string_real( struct xt_node *node, GString *str )
+{
+	char *buf;
+	struct xt_node *c;
+	int i;
+	
+	g_string_append_printf( str, "<%s", node->name );
+	
+	for( i = 0; node->attr[i].key; i ++ )
+	{
+		buf = g_markup_printf_escaped( " %s=\"%s\"", node->attr[i].key, node->attr[i].value );
+		g_string_append( str, buf );
+		g_free( buf );
+	}
+	
+	if( node->text == NULL && node->children == NULL )
+	{
+		g_string_append( str, "/>" );
+		return;
+	}
+	
+	g_string_append( str, ">" );
+	if( node->text_len > 0 )
+	{
+		buf = g_markup_escape_text( node->text, node->text_len );
+		g_string_append( str, buf );
+		g_free( buf );
+	}
+	
+	for( c = node->children; c; c = c->next )
+		xt_to_string_real( c, str );
+	
+	g_string_append_printf( str, "</%s>", node->name );
+}
+
+char *xt_to_string( struct xt_node *node )
+{
+	GString *ret;
+	char *real;
+	
+	ret = g_string_new( "" );
+	xt_to_string_real( node, ret );
+	
+	real = ret->str;
+	g_string_free( ret, FALSE );
+	
+	return real;
+}
+
+#ifdef DEBUG
+void xt_print( struct xt_node *node )
+{
+	int i;
+	struct xt_node *c;
+	
+	/* Indentation */
+	for( c = node; c->parent; c = c->parent )
+		printf( "\t" );
+	
+	/* Start the tag */
+	printf( "<%s", node->name );
+	
+	/* Print the attributes */
+	for( i = 0; node->attr[i].key; i ++ )
+		printf( " %s=\"%s\"", node->attr[i].key, g_markup_escape_text( node->attr[i].value, -1 ) );
+	
+	/* /> in case there's really *nothing* inside this tag, otherwise
+	   just >. */
+	/* If this tag doesn't have any content at all... */
+	if( node->text == NULL && node->children == NULL )
+	{
+		printf( "/>\n" );
+		return;
+		/* Then we're finished! */
+	}
+	
+	/* Otherwise... */
+	printf( ">" );
+	
+	/* Only print the text if it contains more than whitespace (TEST). */
+	if( node->text_len > 0 )
+	{
+		for( i = 0; node->text[i] && isspace( node->text[i] ); i ++ );
+		if( node->text[i] )
+			printf( "%s", g_markup_escape_text( node->text, -1 ) );
+	}
+	
+	if( node->children )
+		printf( "\n" );
+	
+	for( c = node->children; c; c = c->next )
+		xt_print( c );
+	
+	if( node->children )
+		for( c = node; c->parent; c = c->parent )
+			printf( "\t" );
+	
+	/* Non-empty tag is now finished. */
+	printf( "</%s>\n", node->name );
+}
+#endif
+
+struct xt_node *xt_dup( struct xt_node *node )
+{
+	struct xt_node *dup = g_new0( struct xt_node, 1 );
+	struct xt_node *c, *dc = NULL;
+	int i;
+	
+	/* Let's NOT copy the parent element here BTW! Only do it for children. */
+	
+	dup->name = g_strdup( node->name );
+	dup->flags = node->flags;
+	if( node->text )
+	{
+		dup->text = g_memdup( node->text, node->text_len + 1 );
+		dup->text_len = node->text_len;
+	}
+	
+	/* Count the number of attributes and allocate the new array. */
+	for( i = 0; node->attr[i].key; i ++ );
+	dup->attr = g_new0( struct xt_attr, i + 1 );
+	
+	/* Copy them all! */
+	for( i --; i >= 0; i -- )
+	{
+		dup->attr[i].key = g_strdup( node->attr[i].key );
+		dup->attr[i].value = g_strdup( node->attr[i].value );
+	}
+	
+	/* This nice mysterious loop takes care of the children. */
+	for( c = node->children; c; c = c->next )
+	{
+		if( dc == NULL )
+			dc = dup->children = xt_dup( c );
+		else
+			dc = ( dc->next = xt_dup( c ) );
+		
+		dc->parent = dup;
+	}
+	
+	return dup;
+}
+
+/* Frees a node. This doesn't clean up references to itself from parents! */
+void xt_free_node( struct xt_node *node )
+{
+	int i;
+	
+	if( !node )
+		return;
+	
+	g_free( node->name );
+	g_free( node->text );
+	
+	for( i = 0; node->attr[i].key; i ++ )
+	{
+		g_free( node->attr[i].key );
+		g_free( node->attr[i].value );
+	}
+	g_free( node->attr );
+	
+	while( node->children )
+	{
+		struct xt_node *next = node->children->next;
+		
+		xt_free_node( node->children );
+		node->children = next;
+	}
+	
+	g_free( node );
+}
+
+void xt_free( struct xt_parser *xt )
+{
+	if( !xt )
+		return;
+	
+	if( xt->root )
+		xt_free_node( xt->root );
+	
+	g_markup_parse_context_free( xt->parser );
+	
+	g_free( xt );
+}
+
+/* To find a node's child with a specific name, pass the node's children
+   list, not the node itself! The reason you have to do this by hand: So
+   that you can also use this function as a find-next. */
+struct xt_node *xt_find_node( struct xt_node *node, const char *name )
+{
+	while( node )
+	{
+		if( g_strcasecmp( node->name, name ) == 0 )
+			break;
+		
+		node = node->next;
+	}
+	
+	return node;
+}
+
+char *xt_find_attr( struct xt_node *node, const char *key )
+{
+	int i;
+	
+	if( !node )
+		return NULL;
+	
+	for( i = 0; node->attr[i].key; i ++ )
+		if( g_strcasecmp( node->attr[i].key, key ) == 0 )
+			break;
+	
+	return node->attr[i].value;
+}
+
+struct xt_node *xt_new_node( char *name, char *text, struct xt_node *children )
+{
+	struct xt_node *node, *c;
+	
+	node = g_new0( struct xt_node, 1 );
+	node->name = g_strdup( name );
+	node->children = children;
+	node->attr = g_new0( struct xt_attr, 1 );
+	
+	if( text )
+	{
+		node->text_len = strlen( text );
+		node->text = g_memdup( text, node->text_len + 1 );
+	}
+	
+	for( c = children; c; c = c->next )
+	{
+		if( c->parent != NULL )
+		{
+			/* ERROR CONDITION: They seem to have a parent already??? */
+		}
+		
+		c->parent = node;
+	}
+	
+	return node;
+}
+
+void xt_add_child( struct xt_node *parent, struct xt_node *child )
+{
+	struct xt_node *node;
+	
+	/* This function can actually be used to add more than one child, so
+	   do handle this properly. */
+	for( node = child; node; node = node->next )
+	{
+		if( node->parent != NULL )
+		{
+			/* ERROR CONDITION: They seem to have a parent already??? */
+		}
+		
+		node->parent = parent;
+	}
+	
+	if( parent->children == NULL )
+	{
+		parent->children = child;
+	}
+	else
+	{
+		for( node = parent->children; node->next; node = node->next );
+		node->next = child;
+	}
+}
+
+void xt_add_attr( struct xt_node *node, const char *key, const char *value )
+{
+	int i;
+	
+	/* Now actually it'd be nice if we can also change existing attributes
+	   (which actually means this function doesn't have the right name).
+	   So let's find out if we have this attribute already... */
+	for( i = 0; node->attr[i].key; i ++ )
+		if( strcmp( node->attr[i].key, key ) == 0 )
+			break;
+	
+	if( node->attr[i].key == NULL )
+	{
+		/* If not, allocate space for a new attribute. */
+		node->attr = g_renew( struct xt_attr, node->attr, i + 2 );
+		node->attr[i].key = g_strdup( key );
+		node->attr[i+1].key = NULL;
+	}
+	else
+	{
+		/* Otherwise, free the old value before setting the new one. */
+		g_free( node->attr[i].value );
+	}
+	
+	node->attr[i].value = g_strdup( value );
+}
+
+int xt_remove_attr( struct xt_node *node, const char *key )
+{
+	int i, last;
+	
+	for( i = 0; node->attr[i].key; i ++ )
+		if( strcmp( node->attr[i].key, key ) == 0 )
+			break;
+	
+	/* If we didn't find the attribute... */
+	if( node->attr[i].key == NULL )
+		return 0;
+	
+	g_free( node->attr[i].key );
+	g_free( node->attr[i].value );
+	
+	/* If it's the last, this is easy: */
+	if( node->attr[i+1].key == NULL )
+	{
+		node->attr[i].key = node->attr[i].value = NULL;
+	}
+	else /* It's also pretty easy, actually. */
+	{
+		/* Find the last item. */
+		for( last = i + 1; node->attr[last+1].key; last ++ );
+		
+		node->attr[i] = node->attr[last];
+		node->attr[last].key = NULL;
+		node->attr[last].value = NULL;
+	}
+	
+	/* Let's not bother with reallocating memory here. It takes time and
+	   most packets don't stay in memory for long anyway. */
+	
+	return 1;
+}