lua/uci.c

   1 /*
   2  * libuci plugin for Lua
   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 General Public License version 2
   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 #include <sys/types.h>
  16 #include <sys/time.h>
  17 #include <stdlib.h>
  18 #include <string.h>
  19 #include <unistd.h>
  20 #include <stdio.h>
  21 #include <errno.h>
  22
  23 #include <lauxlib.h>
  24 #include <uci.h>
  25
  26 #define MODNAME        "uci"
  27 //#define DEBUG 1
  28
  29 #ifdef DEBUG
  30 #define DPRINTF(...) fprintf(stderr, __VA_ARGS__)
  31 #else
  32 #define DPRINTF(...) do {} while (0)
  33 #endif
  34
  35 static struct uci_context *ctx = NULL;
  36
  37 static struct uci_package *
  38 find_package(const char *name)
  39 {
  40         struct uci_package *p = NULL;
  41         struct uci_element *e;
  42         uci_foreach_element(&ctx->root, e) {
  43                 if (strcmp(e->name, name) != 0)
  44                         continue;
  45
  46                 p = uci_to_package(e);
  47                 break;
  48         }
  49         return p;
  50 }
  51
  52 static void uci_lua_perror(lua_State *L, char *name)
  53 {
  54         lua_getfield(L, LUA_GLOBALSINDEX, "uci");
  55         lua_getfield(L, -1, "warn");
  56         if (!lua_isboolean(L, -1))
  57                 goto done;
  58         if (lua_toboolean(L, -1) != 1)
  59                 goto done;
  60         uci_perror(ctx, name);
  61 done:
  62         lua_pop(L, 2);
  63 }
  64
  65 static int
  66 uci_lua_load(lua_State *L)
  67 {
  68         struct uci_package *p;
  69         const char *s;
  70
  71         luaL_checkany(L, 1);
  72         s = lua_tostring(L, -1);
  73         p = find_package(s);
  74         if (p) {
  75                 uci_unload(ctx, p);
  76                 p = NULL;
  77         }
  78         if (uci_load(ctx, s, &p)) {
  79                 uci_lua_perror(L, "uci.load");
  80                 lua_pushboolean(L, 0);
  81         } else {
  82                 lua_pushboolean(L, 1);
  83         }
  84
  85         return 1;
  86 }
  87
  88 static int
  89 uci_lua_get(lua_State *L)
  90 {
  91         struct uci_lua_context *f;
  92         struct uci_element *e = NULL;
  93         struct uci_package *p = NULL;
  94         char *package = NULL;
  95         char *section = NULL;
  96         char *option = NULL;
  97         char *s;
  98         int err = UCI_ERR_MEM;
  99
 100         luaL_checkany(L, 1);
 101         s = strdup(lua_tostring(L, -1));
 102         if (!s)
 103                 goto error;
 104
 105         if ((err = uci_parse_tuple(ctx, s, &package, &section, &option, NULL)))
 106                 goto error;
 107
 108         if (section == NULL) {
 109                 err = UCI_ERR_INVAL;
 110                 goto error;
 111         }
 112
 113         p = find_package(package);
 114         if (!p) {
 115                 err = UCI_ERR_NOTFOUND;
 116                 goto error;
 117         }
 118
 119         if ((err = uci_lookup(ctx, &e, p, section, option)))
 120                 goto error;
 121
 122         switch(e->type) {
 123                 case UCI_TYPE_SECTION:
 124                         lua_pushstring(L, uci_to_section(e)->type);
 125                         break;
 126                 case UCI_TYPE_OPTION:
 127                         lua_pushstring(L, uci_to_option(e)->value);
 128                         break;
 129                 default:
 130                         err = UCI_ERR_INVAL;
 131                         goto error;
 132         }
 133 error:
 134         if (s)
 135                 free(s);
 136
 137         switch(err) {
 138         default:
 139                 ctx->err = err;
 140                 uci_lua_perror(L, "uci.get");
 141                 /* fall through */
 142         case UCI_ERR_NOTFOUND:
 143                 lua_pushnil(L);
 144                 /* fall through */
 145         case 0:
 146                 return 1;
 147         }
 148 }
 149
 150
 151 static const luaL_Reg uci[] = {
 152         { "load", uci_lua_load },
 153         { "get", uci_lua_get },
 154         { NULL, NULL },
 155 };
 156
 157
 158 int
 159 luaopen_uci(lua_State *L)
 160 {
 161         ctx = uci_alloc_context();
 162         if (!ctx)
 163                 luaL_error(L, "Cannot allocate UCI context\n");
 164         luaL_register(L, MODNAME, uci);
 165         return 0;
 166 }