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