more error handling
[project/uci.git] / list.c
1 /*
2 * libuci - Library for the Unified Configuration Interface
3 * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
4 *
5 * this program is free software; you can redistribute it and/or modify
6 * it under the terms of the gnu lesser general public license version 2.1
7 * as published by the free software foundation
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15 /* initialize a list head/item */
16 static inline void uci_list_init(struct uci_list *ptr)
17 {
18 ptr->prev = ptr;
19 ptr->next = ptr;
20 }
21
22 /* inserts a new list entry between two consecutive entries */
23 static inline void __uci_list_add(struct uci_list *prev, struct uci_list *next, struct uci_list *ptr)
24 {
25 prev->next = ptr;
26 next->prev = ptr;
27 ptr->prev = prev;
28 ptr->next = next;
29 }
30
31 /* inserts a new list entry at the tail of the list */
32 static inline void uci_list_add(struct uci_list *head, struct uci_list *ptr)
33 {
34 /* NB: head->prev points at the tail */
35 __uci_list_add(head->prev, head, ptr);
36 }
37
38 static inline void uci_list_del(struct uci_list *ptr)
39 {
40 struct uci_list *next, *prev;
41
42 next = ptr->next;
43 prev = ptr->prev;
44
45 prev->next = next;
46 next->prev = prev;
47 }
48
49 static void uci_drop_section(struct uci_section *section)
50 {
51 if (!section)
52 return;
53 if (section->name)
54 free(section->name);
55 if (section->type)
56 free(section->type);
57 free(section);
58 }
59
60 static struct uci_section *uci_add_section(struct uci_config *cfg, const char *type, const char *name)
61 {
62 struct uci_section *section = NULL;
63 struct uci_context *ctx = cfg->ctx;
64
65 UCI_TRAP_SAVE(ctx, error)
66 section = (struct uci_section *) uci_malloc(ctx, sizeof(struct uci_section));
67 section->config = cfg;
68 uci_list_init(&section->list);
69 uci_list_init(&section->options);
70 uci_list_add(&cfg->sections, &section->list);
71 section->type = uci_strdup(ctx, type);
72 if (name)
73 section->name = uci_strdup(ctx, name);
74 UCI_TRAP_RESTORE(ctx);
75
76 return section;
77
78 error:
79 uci_drop_section(section);
80 UCI_THROW(ctx, ctx->errno);
81 return NULL;
82 }
83
84 static void uci_drop_file(struct uci_config *cfg)
85 {
86 /* TODO: free children */
87 if(!cfg)
88 return;
89 if (cfg->name)
90 free(cfg->name);
91 free(cfg);
92 }
93
94
95 static struct uci_config *uci_alloc_file(struct uci_context *ctx, const char *name)
96 {
97 struct uci_config *cfg = NULL;
98
99 UCI_TRAP_SAVE(ctx, error)
100 cfg = (struct uci_config *) uci_malloc(ctx, sizeof(struct uci_config));
101 uci_list_init(&cfg->list);
102 uci_list_init(&cfg->sections);
103 cfg->name = uci_strdup(ctx, name);
104 cfg->ctx = ctx;
105 UCI_TRAP_RESTORE(ctx);
106 return cfg;
107
108 error:
109 uci_drop_file(cfg);
110 UCI_THROW(ctx, ctx->errno);
111 return NULL;
112 }
113