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 Lesser 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 <dlfcn.h>
  26 #include <glob.h>
  27 #include "uci.h"
  28
  29 static const char *uci_errstr[] = {
  30         [UCI_OK] =            "Success",
  31         [UCI_ERR_MEM] =       "Out of memory",
  32         [UCI_ERR_INVAL] =     "Invalid argument",
  33         [UCI_ERR_NOTFOUND] =  "Entry not found",
  34         [UCI_ERR_IO] =        "I/O error",
  35         [UCI_ERR_PARSE] =     "Parse error",
  36         [UCI_ERR_DUPLICATE] = "Duplicate entry",
  37         [UCI_ERR_UNKNOWN] =   "Unknown error",
  38 };
  39
  40 #include "uci_internal.h"
  41 #include "list.c"
  42
  43 __private const char *uci_confdir = UCI_CONFDIR;
  44 __private const char *uci_savedir = UCI_SAVEDIR;
  45
  46 /* exported functions */
  47 struct uci_context *uci_alloc_context(void)
  48 {
  49         struct uci_context *ctx;
  50
  51         ctx = (struct uci_context *) calloc(1, sizeof(struct uci_context));
  52         if (!ctx)
  53                 return NULL;
  54
  55         uci_list_init(&ctx->root);
  56         uci_list_init(&ctx->delta_path);
  57         uci_list_init(&ctx->backends);
  58         ctx->flags = UCI_FLAG_STRICT | UCI_FLAG_SAVED_DELTA;
  59
  60         ctx->confdir = (char *) uci_confdir;
  61         ctx->savedir = (char *) uci_savedir;
  62         uci_add_delta_path(ctx, 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->delta_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 __private 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] = { 0 };
 143         int err;
 144
 145         err = ctx ? ctx->err : UCI_ERR_INVAL;
 146         if ((err < 0) || (err >= UCI_ERR_LAST))
 147                 err = UCI_ERR_UNKNOWN;
 148
 149         if (ctx && ctx->pctx && (err == UCI_ERR_PARSE)) {
 150                 snprintf(error_info, sizeof(error_info) - 1, " (%s) at line %d, byte %zu",
 151                          (ctx->pctx->reason ? ctx->pctx->reason : "unknown"),
 152                          ctx->pctx->line, ctx->pctx->byte);
 153         }
 154
 155         if (!dest) {
 156                 strcat(error_info, "\n");
 157                 fprintf(stderr, "%s%s%s%s%s%s",
 158                         (prefix ? prefix : ""), (prefix ? ": " : ""),
 159                         (ctx && ctx->func ? ctx->func : ""), (ctx && ctx->func ? ": " : ""),
 160                         uci_errstr[err],
 161                         error_info);
 162                 return;
 163         }
 164
 165         err = asprintf(dest, "%s%s%s%s%s%s",
 166                 (prefix ? prefix : ""), (prefix ? ": " : ""),
 167                 (ctx && ctx->func ? ctx->func : ""), (ctx && ctx->func ? ": " : ""),
 168                 uci_errstr[err],
 169                 error_info);
 170
 171         if (err < 0)
 172                 *dest = NULL;
 173 }
 174
 175 int uci_list_configs(struct uci_context *ctx, char ***list)
 176 {
 177         UCI_HANDLE_ERR(ctx);
 178         UCI_ASSERT(ctx, list != NULL);
 179         UCI_ASSERT(ctx, ctx->backend && ctx->backend->list_configs);
 180         *list = ctx->backend->list_configs(ctx);
 181         return 0;
 182 }
 183
 184 int uci_commit(struct uci_context *ctx, struct uci_package **package, bool overwrite)
 185 {
 186         struct uci_package *p;
 187         UCI_HANDLE_ERR(ctx);
 188         UCI_ASSERT(ctx, package != NULL);
 189         p = *package;
 190         UCI_ASSERT(ctx, p != NULL);
 191         UCI_ASSERT(ctx, p->backend && p->backend->commit);
 192         p->backend->commit(ctx, package, overwrite);
 193         return 0;
 194 }
 195
 196 int uci_load(struct uci_context *ctx, const char *name, struct uci_package **package)
 197 {
 198         struct uci_package *p;
 199
 200         UCI_HANDLE_ERR(ctx);
 201         UCI_ASSERT(ctx, ctx->backend && ctx->backend->load);
 202         p = ctx->backend->load(ctx, name);
 203         if (package)
 204                 *package = p;
 205
 206         return 0;
 207 }
 208
 209 int uci_set_backend(struct uci_context *ctx, const char *name)
 210 {
 211         struct uci_element *e;
 212
 213         UCI_HANDLE_ERR(ctx);
 214         UCI_ASSERT(ctx, name != NULL);
 215         e = uci_lookup_list(&ctx->backends, name);
 216         if (!e)
 217                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 218         ctx->backend = uci_to_backend(e);
 219         return 0;
 220 }