1 /* -*- mode: c; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: t -*-
2 * vim: ts=4 sw=4 noet ai cindent syntax=c
4 * Conky, a system monitor, based on torsmo
6 * Any original torsmo code is licensed under the BSD license
8 * All code written since the fork of torsmo is licensed under the GPL
10 * Please see COPYING for details
12 * Copyright (c) 2005-2010 Brenden Matthews, Philip Kovacs, et. al.
14 * All rights reserved.
16 * This program is free software: you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License as published by
18 * the Free Software Foundation, either version 3 of the License, or
19 * (at your option) any later version.
21 * This program is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24 * GNU General Public License for more details.
25 * You should have received a copy of the GNU General Public License
26 * along with this program. If not, see <http://www.gnu.org/licenses/>.
29 #include "text_object.h"
36 * this list is special. it looks like this:
37 * NULL <-- obj1 <--> obj2 <--> ... <--> objN --> NULL
38 * ^-------root_object----------^
39 * directions are reversed here
42 * - root_object points both to the start and end of the list
43 * - while traversing, the end of the list is always a NULL pointer
44 * (this works in BOTH directions)
47 /* append an object to the given root object's list */
48 int append_object(struct text_object *root, struct text_object *obj)
50 struct text_object *end;
58 CRIT_ERR(NULL, NULL, "huston, we have a lift-off");
67 /* ifblock handlers for the object list
69 * - each if points to it's else or endif
70 * - each else points to it's endif
74 /* possible ifblock types
75 * only used internally, so no need to make this public
83 /* linked list of ifblock objects, building a stack
84 * only used internally, so no need to make this public
86 struct ifblock_stack_obj {
87 enum ifblock_type type;
88 struct text_object *obj;
89 struct ifblock_stack_obj *next;
92 /* push an ifblock object onto the stack
93 * in fact, this does a lot more:
94 * - IFBLOCK_IF is just pushed onto the stack
95 * - IFBLOCK_ELSE updates the "next" pointer of the upmost
96 * object in the stack and is then pushed onto the stack
97 * - IFBLOCK_ENDIF updates the "next" pointer of the upmost
98 * object in the stack and then triggers stack popping of
99 * any optional IFBLOCK_ELSE along with it's IFBLOCK_IF
101 static int push_ifblock(struct ifblock_stack_obj **ifblock_stack_top,
102 struct text_object *obj, enum ifblock_type type)
104 struct ifblock_stack_obj *stackobj;
108 if (!(*ifblock_stack_top))
109 CRIT_ERR(NULL, NULL, "got an endif without matching if");
110 (*ifblock_stack_top)->obj->ifblock_next = obj;
111 /* if there's some else in between, remove and free it */
112 if ((*ifblock_stack_top)->type == IFBLOCK_ELSE) {
113 stackobj = *ifblock_stack_top;
114 *ifblock_stack_top = stackobj->next;
117 /* finally remove and free the if object */
118 stackobj = *ifblock_stack_top;
119 *ifblock_stack_top = stackobj->next;
123 if (!(*ifblock_stack_top))
124 CRIT_ERR(NULL, NULL, "got an else without matching if");
125 (*ifblock_stack_top)->obj->ifblock_next = obj;
128 stackobj = malloc(sizeof(struct ifblock_stack_obj));
129 stackobj->type = type;
131 stackobj->next = *ifblock_stack_top;
132 *ifblock_stack_top = stackobj;
135 CRIT_ERR(NULL, NULL, "push_ifblock() missuse detected!");
140 /* public functions for client use */
142 int obj_be_ifblock_if(void **opaque, struct text_object *obj)
144 return push_ifblock((struct ifblock_stack_obj **)opaque, obj, IFBLOCK_IF);
146 int obj_be_ifblock_else(void **opaque, struct text_object *obj)
148 return push_ifblock((struct ifblock_stack_obj **)opaque, obj, IFBLOCK_ELSE);
150 int obj_be_ifblock_endif(void **opaque, struct text_object *obj)
152 return push_ifblock((struct ifblock_stack_obj **)opaque, obj, IFBLOCK_ENDIF);
155 /* check if ifblock stack is empty
156 * if so, return true (!= 0)
158 int ifblock_stack_empty(void **opaque)
160 return *opaque == NULL;