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 \*-------------------------------------------------------------------------*/
auxiliar_open(lua_State * L)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 \*-------------------------------------------------------------------------*/
auxiliar_newclass(lua_State * L,const char * classname,luaL_Reg * func)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 \*-------------------------------------------------------------------------*/
auxiliar_tostring(lua_State * L)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 \*-------------------------------------------------------------------------*/
auxiliar_add2group(lua_State * L,const char * classname,const char * groupname)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 \*-------------------------------------------------------------------------*/
auxiliar_checkboolean(lua_State * L,int objidx)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 \*-------------------------------------------------------------------------*/
auxiliar_checkclass(lua_State * L,const char * classname,int objidx)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 \*-------------------------------------------------------------------------*/
auxiliar_checkgroup(lua_State * L,const char * groupname,int objidx)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 \*-------------------------------------------------------------------------*/
auxiliar_setclass(lua_State * L,const char * classname,int objidx)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 \*-------------------------------------------------------------------------*/
auxiliar_getgroupudata(lua_State * L,const char * groupname,int objidx)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 \*-------------------------------------------------------------------------*/
auxiliar_getclassudata(lua_State * L,const char * classname,int objidx)145 void *auxiliar_getclassudata(lua_State *L, const char *classname, int objidx) {
146 return luaL_testudata(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 \*-------------------------------------------------------------------------*/
auxiliar_typeerror(lua_State * L,int narg,const char * tname)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