libuci.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 /*
  16  * This file contains some common code for the uci library
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <sys/types.h>
  21 #include <stdbool.h>
  22 #include <string.h>
  23 #include <stdlib.h>
  24 #include <stdio.h>
  25 #include "uci.h"
  26
  27 static const char *uci_confdir = UCI_CONFDIR;
  28 static const char *uci_savedir = UCI_SAVEDIR;
  29
  30 static const char *uci_errstr[] = {
  31         [UCI_OK] =            "Success",
  32         [UCI_ERR_MEM] =       "Out of memory",
  33         [UCI_ERR_INVAL] =     "Invalid argument",
  34         [UCI_ERR_NOTFOUND] =  "Entry not found",
  35         [UCI_ERR_IO] =        "I/O error",
  36         [UCI_ERR_PARSE] =     "Parse error",
  37         [UCI_ERR_DUPLICATE] = "Duplicate entry",
  38         [UCI_ERR_UNKNOWN] =   "Unknown error",
  39 };
  40
  41 static void uci_cleanup(struct uci_context *ctx);
  42
  43 #include "uci_internal.h"
  44 #include "util.c"
  45 #include "list.c"
  46 #include "history.c"
  47 #include "file.c"
  48
  49 /* exported functions */
  50 struct uci_context *uci_alloc_context(void)
  51 {
  52         struct uci_context *ctx;
  53
  54         ctx = (struct uci_context *) malloc(sizeof(struct uci_context));
  55         memset(ctx, 0, sizeof(struct uci_context));
  56         uci_list_init(&ctx->root);
  57         uci_list_init(&ctx->history_path);
  58         uci_list_init(&ctx->backends);
  59         ctx->flags = UCI_FLAG_STRICT | UCI_FLAG_SAVED_HISTORY;
  60
  61         ctx->confdir = (char *) uci_confdir;
  62         ctx->savedir = (char *) uci_savedir;
  63
  64         uci_list_add(&ctx->backends, &uci_file_backend.e.list);
  65         ctx->backend = &uci_file_backend;
  66
  67         return ctx;
  68 }
  69
  70 void uci_free_context(struct uci_context *ctx)
  71 {
  72         struct uci_element *e, *tmp;
  73
  74         if (ctx->confdir != uci_confdir)
  75                 free(ctx->confdir);
  76         if (ctx->savedir != uci_savedir)
  77                 free(ctx->savedir);
  78
  79         uci_cleanup(ctx);
  80         UCI_TRAP_SAVE(ctx, ignore);
  81         uci_foreach_element_safe(&ctx->root, tmp, e) {
  82                 struct uci_package *p = uci_to_package(e);
  83                 uci_free_package(&p);
  84         }
  85         uci_foreach_element_safe(&ctx->history_path, tmp, e) {
  86                 uci_free_element(e);
  87         }
  88         UCI_TRAP_RESTORE(ctx);
  89         free(ctx);
  90
  91 ignore:
  92         return;
  93 }
  94
  95 int uci_set_confdir(struct uci_context *ctx, const char *dir)
  96 {
  97         char *cdir;
  98
  99         UCI_HANDLE_ERR(ctx);
 100         UCI_ASSERT(ctx, dir != NULL);
 101
 102         cdir = uci_strdup(ctx, dir);
 103         if (ctx->confdir != uci_confdir)
 104                 free(ctx->confdir);
 105         ctx->confdir = cdir;
 106         return 0;
 107 }
 108
 109 static void uci_cleanup(struct uci_context *ctx)
 110 {
 111         struct uci_parse_context *pctx;
 112
 113         if (ctx->buf) {
 114                 free(ctx->buf);
 115                 ctx->buf = NULL;
 116                 ctx->bufsz = 0;
 117         }
 118
 119         pctx = ctx->pctx;
 120         if (!pctx)
 121                 return;
 122
 123         ctx->pctx = NULL;
 124         if (pctx->package)
 125                 uci_free_package(&pctx->package);
 126
 127         if (pctx->buf)
 128                 free(pctx->buf);
 129
 130         free(pctx);
 131 }
 132
 133 void
 134 uci_perror(struct uci_context *ctx, const char *str)
 135 {
 136         uci_get_errorstr(ctx, NULL, str);
 137 }
 138
 139 void
 140 uci_get_errorstr(struct uci_context *ctx, char **dest, const char *prefix)
 141 {
 142         static char error_info[128];
 143         int err;
 144         const char *format =
 145                 "%s%s" /* prefix */
 146                 "%s%s" /* function */
 147                 "%s" /* error */
 148                 "%s"; /* details */
 149
 150         error_info[0] = 0;
 151
 152         if (!ctx)
 153                 err = UCI_ERR_INVAL;
 154         else
 155                 err = ctx->err;
 156
 157         if ((err < 0) || (err >= UCI_ERR_LAST))
 158                 err = UCI_ERR_UNKNOWN;
 159
 160         switch (err) {
 161         case UCI_ERR_PARSE:
 162                 if (ctx->pctx) {
 163                         snprintf(error_info, sizeof(error_info) - 1, " (%s) at line %d, byte %d", (ctx->pctx->reason ? ctx->pctx->reason : "unknown"), ctx->pctx->line, ctx->pctx->byte);
 164                         break;
 165                 }
 166                 break;
 167         default:
 168                 break;
 169         }
 170         if (dest) {
 171                 err = asprintf(dest, format,
 172                         (prefix ? prefix : ""), (prefix ? ": " : ""),
 173                         (ctx->func ? ctx->func : ""), (ctx->func ? ": " : ""),
 174                         uci_errstr[err],
 175                         error_info);
 176                 if (err < 0)
 177                         *dest = NULL;
 178         } else {
 179                 strcat(error_info, "\n");
 180                 fprintf(stderr, format,
 181                         (prefix ? prefix : ""), (prefix ? ": " : ""),
 182                         (ctx->func ? ctx->func : ""), (ctx->func ? ": " : ""),
 183                         uci_errstr[err],
 184                         error_info);
 185         }
 186 }
 187
 188 int uci_list_configs(struct uci_context *ctx, char ***list)
 189 {
 190         UCI_HANDLE_ERR(ctx);
 191         UCI_ASSERT(ctx, list != NULL);
 192         UCI_ASSERT(ctx, ctx->backend && ctx->backend->list_configs);
 193         *list = ctx->backend->list_configs(ctx);
 194         return 0;
 195 }
 196
 197 int uci_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
 198 {
 199         struct uci_package *p;
 200         UCI_HANDLE_ERR(ctx);
 201         UCI_ASSERT(ctx, package != NULL);
 202         p = *package;
 203         UCI_ASSERT(ctx, p != NULL);
 204         UCI_ASSERT(ctx, p->backend && p->backend->commit);
 205         p->backend->commit(ctx, package, overwrite);
 206         return 0;
 207 }
 208
 209 int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package)
 210 {
 211         struct uci_package *p;
 212         UCI_HANDLE_ERR(ctx);
 213         UCI_ASSERT(ctx, ctx->backend && ctx->backend->load);
 214         p = ctx->backend->load(ctx, name);
 215         if (package)
 216                 *package = p;
 217
 218         return 0;
 219 }
 220
 221 #ifdef UCI_PLUGIN_SUPPORT
 222
 223 __plugin int uci_add_backend(struct uci_context *ctx, struct uci_backend *b)
 224 {
 225         struct uci_element *e;
 226         UCI_HANDLE_ERR(ctx);
 227
 228         e = uci_lookup_list(&ctx->backends, b->e.name);
 229         if (e)
 230                 UCI_THROW(ctx, UCI_ERR_DUPLICATE);
 231
 232         e = uci_malloc(ctx, sizeof(struct uci_backend));
 233         memcpy(e, b, sizeof(struct uci_backend));
 234
 235         uci_list_add(&ctx->backends, &e->list);
 236         return 0;
 237 }
 238
 239 __plugin int uci_del_backend(struct uci_context *ctx, struct uci_backend *b)
 240 {
 241         struct uci_element *e, *tmp;
 242
 243         UCI_HANDLE_ERR(ctx);
 244
 245         e = uci_lookup_list(&ctx->backends, b->e.name);
 246         if (!e || uci_to_backend(e)->ptr != b->ptr)
 247                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 248         b = uci_to_backend(e);
 249
 250         if (ctx->backend && ctx->backend->ptr == b->ptr)
 251                 ctx->backend = &uci_file_backend;
 252
 253         uci_foreach_element_safe(&ctx->root, tmp, e) {
 254                 struct uci_package *p = uci_to_package(e);
 255
 256                 if (!p->backend)
 257                         continue;
 258
 259                 if (p->backend->ptr == b->ptr)
 260                         UCI_INTERNAL(uci_unload, ctx, p);
 261         }
 262
 263         uci_list_del(&b->e.list);
 264         free(b);
 265
 266         return 0;
 267 }
 268
 269 #endif
 270
 271 int uci_set_backend(struct uci_context *ctx, const char *name)
 272 {
 273         struct uci_element *e;
 274
 275         UCI_HANDLE_ERR(ctx);
 276         UCI_ASSERT(ctx, name != NULL);
 277         e = uci_lookup_list(&ctx->backends, name);
 278         if (!e)
 279                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 280         ctx->backend = uci_to_backend(e);
 281         return 0;
 282 }