| 1 | /*=========================================================================*\ |
| 2 | * Auxiliar routines for class hierarchy manipulation |
| 3 | * LuaSocket toolkit |
| 4 | \*=========================================================================*/ |
| 5 | #include <string.h> |
| 6 | #include <stdio.h> |
| 7 | |
| 8 | #include "auxiliar.h" |
| 9 | |
| 10 | /*=========================================================================*\ |
| 11 | * Exported functions |
| 12 | \*=========================================================================*/ |
| 13 | /*-------------------------------------------------------------------------*\ |
| 14 | * Initializes the module |
| 15 | \*-------------------------------------------------------------------------*/ |
| 16 | int auxiliar_open(lua_State *L) { |
| 17 | (void) L; |
| 18 | return 0; |
| 19 | } |
| 20 | |
| 21 | /*-------------------------------------------------------------------------*\ |
| 22 | * Creates a new class with given methods |
| 23 | * Methods whose names start with __ are passed directly to the metatable. |
| 24 | \*-------------------------------------------------------------------------*/ |
| 25 | void auxiliar_newclass(lua_State *L, const char *classname, luaL_Reg *func) { |
| 26 | luaL_newmetatable(L, classname); /* mt */ |
| 27 | /* create __index table to place methods */ |
| 28 | lua_pushstring(L, "__index" ); /* mt,"__index" */ |
| 29 | lua_newtable(L); /* mt,"__index",it */ |
| 30 | /* put class name into class metatable */ |
| 31 | lua_pushstring(L, "class" ); /* mt,"__index",it,"class" */ |
| 32 | lua_pushstring(L, classname); /* mt,"__index",it,"class",classname */ |
| 33 | lua_rawset(L, -3); /* mt,"__index",it */ |
| 34 | /* pass all methods that start with _ to the metatable, and all others |
| 35 | * to the index table */ |
| 36 | for (; func->name; func++) { /* mt,"__index",it */ |
| 37 | lua_pushstring(L, func->name); |
| 38 | lua_pushcfunction(L, func->func); |
| 39 | lua_rawset(L, func->name[0] == '_' ? -5: -3); |
| 40 | } |
| 41 | lua_rawset(L, -3); /* mt */ |
| 42 | lua_pop(L, 1); |
| 43 | } |
| 44 | |
| 45 | /*-------------------------------------------------------------------------*\ |
| 46 | * Prints the value of a class in a nice way |
| 47 | \*-------------------------------------------------------------------------*/ |
| 48 | int auxiliar_tostring(lua_State *L) { |
| 49 | char buf[32]; |
| 50 | if (!lua_getmetatable(L, 1)) goto error; |
| 51 | lua_pushstring(L, "__index" ); |
| 52 | lua_gettable(L, -2); |
| 53 | if (!lua_istable(L, -1)) goto error; |
| 54 | lua_pushstring(L, "class" ); |
| 55 | lua_gettable(L, -2); |
| 56 | if (!lua_isstring(L, -1)) goto error; |
| 57 | sprintf(buf, "%p" , lua_touserdata(L, 1)); |
| 58 | lua_pushfstring(L, "%s: %s" , lua_tostring(L, -1), buf); |
| 59 | return 1; |
| 60 | error: |
| 61 | lua_pushstring(L, "invalid object passed to 'auxiliar.c:__tostring'" ); |
| 62 | lua_error(L); |
| 63 | return 1; |
| 64 | } |
| 65 | |
| 66 | /*-------------------------------------------------------------------------*\ |
| 67 | * Insert class into group |
| 68 | \*-------------------------------------------------------------------------*/ |
| 69 | void auxiliar_add2group(lua_State *L, const char *classname, const char *groupname) { |
| 70 | luaL_getmetatable(L, classname); |
| 71 | lua_pushstring(L, groupname); |
| 72 | lua_pushboolean(L, 1); |
| 73 | lua_rawset(L, -3); |
| 74 | lua_pop(L, 1); |
| 75 | } |
| 76 | |
| 77 | /*-------------------------------------------------------------------------*\ |
| 78 | * Make sure argument is a boolean |
| 79 | \*-------------------------------------------------------------------------*/ |
| 80 | int auxiliar_checkboolean(lua_State *L, int objidx) { |
| 81 | if (!lua_isboolean(L, objidx)) |
| 82 | auxiliar_typeerror(L, objidx, lua_typename(L, LUA_TBOOLEAN)); |
| 83 | return lua_toboolean(L, objidx); |
| 84 | } |
| 85 | |
| 86 | /*-------------------------------------------------------------------------*\ |
| 87 | * Return userdata pointer if object belongs to a given class, abort with |
| 88 | * error otherwise |
| 89 | \*-------------------------------------------------------------------------*/ |
| 90 | void *auxiliar_checkclass(lua_State *L, const char *classname, int objidx) { |
| 91 | void *data = auxiliar_getclassudata(L, classname, objidx); |
| 92 | if (!data) { |
| 93 | char msg[45]; |
| 94 | sprintf(msg, "%.35s expected" , classname); |
| 95 | luaL_argerror(L, objidx, msg); |
| 96 | } |
| 97 | return data; |
| 98 | } |
| 99 | |
| 100 | /*-------------------------------------------------------------------------*\ |
| 101 | * Return userdata pointer if object belongs to a given group, abort with |
| 102 | * error otherwise |
| 103 | \*-------------------------------------------------------------------------*/ |
| 104 | void *auxiliar_checkgroup(lua_State *L, const char *groupname, int objidx) { |
| 105 | void *data = auxiliar_getgroupudata(L, groupname, objidx); |
| 106 | if (!data) { |
| 107 | char msg[45]; |
| 108 | sprintf(msg, "%.35s expected" , groupname); |
| 109 | luaL_argerror(L, objidx, msg); |
| 110 | } |
| 111 | return data; |
| 112 | } |
| 113 | |
| 114 | /*-------------------------------------------------------------------------*\ |
| 115 | * Set object class |
| 116 | \*-------------------------------------------------------------------------*/ |
| 117 | void auxiliar_setclass(lua_State *L, const char *classname, int objidx) { |
| 118 | luaL_getmetatable(L, classname); |
| 119 | if (objidx < 0) objidx--; |
| 120 | lua_setmetatable(L, objidx); |
| 121 | } |
| 122 | |
| 123 | /*-------------------------------------------------------------------------*\ |
| 124 | * Get a userdata pointer if object belongs to a given group. Return NULL |
| 125 | * otherwise |
| 126 | \*-------------------------------------------------------------------------*/ |
| 127 | void *auxiliar_getgroupudata(lua_State *L, const char *groupname, int objidx) { |
| 128 | if (!lua_getmetatable(L, objidx)) |
| 129 | return NULL; |
| 130 | lua_pushstring(L, groupname); |
| 131 | lua_rawget(L, -2); |
| 132 | if (lua_isnil(L, -1)) { |
| 133 | lua_pop(L, 2); |
| 134 | return NULL; |
| 135 | } else { |
| 136 | lua_pop(L, 2); |
| 137 | return lua_touserdata(L, objidx); |
| 138 | } |
| 139 | } |
| 140 | |
| 141 | /*-------------------------------------------------------------------------*\ |
| 142 | * Get a userdata pointer if object belongs to a given class. Return NULL |
| 143 | * otherwise |
| 144 | \*-------------------------------------------------------------------------*/ |
| 145 | void *auxiliar_getclassudata(lua_State *L, const char *classname, int objidx) { |
| 146 | return luaL_checkudata(L, objidx, classname); |
| 147 | } |
| 148 | |
| 149 | /*-------------------------------------------------------------------------*\ |
| 150 | * Throws error when argument does not have correct type. |
| 151 | * Used to be part of lauxlib in Lua 5.1, was dropped from 5.2. |
| 152 | \*-------------------------------------------------------------------------*/ |
| 153 | int auxiliar_typeerror (lua_State *L, int narg, const char *tname) { |
| 154 | const char *msg = lua_pushfstring(L, "%s expected, got %s" , tname, |
| 155 | luaL_typename(L, narg)); |
| 156 | return luaL_argerror(L, narg, msg); |
| 157 | } |
| 158 | |
| 159 | |