libs/lmo/src/lmo_lualib.c

   1 /*
   2  * lmo - Lua Machine Objects - Lua binding
   3  *
   4  *   Copyright (C) 2009 Jo-Philipp Wich <xm@subsignal.org>
   5  *
   6  *  Licensed under the Apache License, Version 2.0 (the "License");
   7  *  you may not use this file except in compliance with the License.
   8  *  You may obtain a copy of the License at
   9  *
  10  *      http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  *  Unless required by applicable law or agreed to in writing, software
  13  *  distributed under the License is distributed on an "AS IS" BASIS,
  14  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  *  See the License for the specific language governing permissions and
  16  *  limitations under the License.
  17  */
  18
  19 #include "lmo_lualib.h"
  20
  21 extern char _lmo_error[1024];
  22
  23
  24 static int lmo_L_open(lua_State *L) {
  25         const char *filename = luaL_checklstring(L, 1, NULL);
  26         lmo_archive_t *ar, **udata;
  27
  28         if( (ar = lmo_open(filename)) != NULL )
  29         {
  30                 if( (udata = lua_newuserdata(L, sizeof(lmo_archive_t *))) != NULL )
  31                 {
  32                         *udata = ar;
  33                         luaL_getmetatable(L, LMO_ARCHIVE_META);
  34                         lua_setmetatable(L, -2);
  35                         return 1;
  36                 }
  37
  38                 lmo_close(ar);
  39                 lua_pushnil(L);
  40                 lua_pushstring(L, "out of memory");
  41                 return 2;
  42         }
  43
  44         lua_pushnil(L);
  45         lua_pushstring(L, lmo_error());
  46         return 2;
  47 }
  48
  49 static int lmo_L_hash(lua_State *L) {
  50         const char *data = luaL_checkstring(L, 1);
  51         uint32_t hash = sfh_hash(data, strlen(data));
  52         lua_pushinteger(L, (lua_Integer)hash);
  53         return 1;
  54 }
  55
  56 static int _lmo_lookup(lua_State *L, lmo_archive_t *ar, uint32_t hash) {
  57         lmo_entry_t *e = ar->index;
  58
  59         while( e != NULL )
  60         {
  61                 if( e->key_id == hash )
  62                 {
  63                         lua_pushlstring(L, &ar->mmap[e->offset], e->length);
  64                         return 1;
  65                 }
  66
  67                 e = e->next;
  68         }
  69
  70         lua_pushnil(L);
  71         return 1;
  72 }
  73
  74 static int lmo_L_get(lua_State *L) {
  75         lmo_archive_t **ar = luaL_checkudata(L, 1, LMO_ARCHIVE_META);
  76         uint32_t hash = (uint32_t) luaL_checkinteger(L, 2);
  77         return _lmo_lookup(L, *ar, hash);
  78 }
  79
  80 static int lmo_L_lookup(lua_State *L) {
  81         lmo_archive_t **ar = luaL_checkudata(L, 1, LMO_ARCHIVE_META);
  82         const char *key = luaL_checkstring(L, 2);
  83         uint32_t hash = sfh_hash(key, strlen(key));
  84         return _lmo_lookup(L, *ar, hash);
  85 }
  86
  87 static int lmo_L_foreach(lua_State *L) {
  88         lmo_archive_t **ar = luaL_checkudata(L, 1, LMO_ARCHIVE_META);
  89         lmo_entry_t *e = (*ar)->index;
  90
  91         if( lua_isfunction(L, 2) )
  92         {
  93                 while( e != NULL )
  94                 {
  95                         lua_pushvalue(L, 2);
  96                         lua_pushinteger(L, e->key_id);
  97                         lua_pushlstring(L, &(*ar)->mmap[e->offset], e->length);
  98                         lua_pcall(L, 2, 0, 0);
  99                         e = e->next;
 100                 }
 101         }
 102
 103         return 0;
 104 }
 105
 106 static int lmo_L__gc(lua_State *L) {
 107         lmo_archive_t **ar = luaL_checkudata(L, 1, LMO_ARCHIVE_META);
 108
 109         if( (*ar) != NULL )
 110                 lmo_close(*ar);
 111
 112         *ar = NULL;
 113
 114         return 0;
 115 }
 116
 117 static int lmo_L__tostring(lua_State *L) {
 118         lmo_archive_t **ar = luaL_checkudata(L, 1, LMO_ARCHIVE_META);
 119         lua_pushfstring(L, "LMO Archive (%d bytes)", (*ar)->length);
 120         return 1;
 121 }
 122
 123
 124 /* method table */
 125 static const luaL_reg M[] = {
 126         {"close",       lmo_L__gc},
 127         {"get",         lmo_L_get},
 128         {"lookup",      lmo_L_lookup},
 129         {"foreach",     lmo_L_foreach},
 130         {"__tostring",  lmo_L__tostring},
 131         {"__gc",        lmo_L__gc},
 132         {NULL,          NULL}
 133 };
 134
 135 /* module table */
 136 static const luaL_reg R[] = {
 137         {"open",        lmo_L_open},
 138         {"hash",        lmo_L_hash},
 139         {NULL,          NULL}
 140 };
 141
 142 LUALIB_API int luaopen_lmo(lua_State *L) {
 143         luaL_newmetatable(L, LMO_ARCHIVE_META);
 144         luaL_register(L, NULL, M);
 145         lua_pushvalue(L, -1);
 146         lua_setfield(L, -2, "__index");
 147         lua_setglobal(L, LMO_ARCHIVE_META);
 148
 149         luaL_register(L, LMO_LUALIB_META, R);
 150
 151         return 1;
 152 }