src/lib/ldblib.c

   1 /*
   2 ** $Id: ldblib.c,v 1.29 2000/11/06 17:58:38 roberto Exp $
   3 ** Interface from Lua to its debug API
   4 ** See Copyright Notice in lua.h
   5 */
   6
   7
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11
  12 #include "lua.h"
  13
  14 #include "lauxlib.h"
  15 #include "luadebug.h"
  16 #include "lualib.h"
  17
  18
  19
  20 static void settabss (lua_State *L, const char *i, const char *v) {
  21   lua_pushstring(L, i);
  22   lua_pushstring(L, v);
  23   lua_settable(L, -3);
  24 }
  25
  26
  27 static void settabsi (lua_State *L, const char *i, int v) {
  28   lua_pushstring(L, i);
  29   lua_pushnumber(L, v);
  30   lua_settable(L, -3);
  31 }
  32
  33
  34 static int getinfo (lua_State *L) {
  35   lua_Debug ar;
  36   const char *options = luaL_opt_string(L, 2, "flnSu");
  37   char buff[20];
  38   if (lua_isnumber(L, 1)) {
  39     if (!lua_getstack(L, (int)lua_tonumber(L, 1), &ar)) {
  40       lua_pushnil(L);  /* level out of range */
  41       return 1;
  42     }
  43   }
  44   else if (lua_isfunction(L, 1)) {
  45     lua_pushvalue(L, 1);
  46     sprintf(buff, ">%.10s", options);
  47     options = buff;
  48   }
  49   else
  50     luaL_argerror(L, 1, "function or level expected");
  51   if (!lua_getinfo(L, options, &ar))
  52     luaL_argerror(L, 2, "invalid option");
  53   lua_newtable(L);
  54   for (; *options; options++) {
  55     switch (*options) {
  56       case 'S':
  57         settabss(L, "source", ar.source);
  58         if (ar.source)
  59           settabss(L, "short_src", ar.short_src);
  60         settabsi(L, "linedefined", ar.linedefined);
  61         settabss(L, "what", ar.what);
  62         break;
  63       case 'l':
  64         settabsi(L, "currentline", ar.currentline);
  65         break;
  66       case 'u':
  67         settabsi(L, "nups", ar.nups);
  68         break;
  69       case 'n':
  70         settabss(L, "name", ar.name);
  71         settabss(L, "namewhat", ar.namewhat);
  72         break;
  73       case 'f':
  74         lua_pushstring(L, "func");
  75         lua_pushvalue(L, -3);
  76         lua_settable(L, -3);
  77         break;
  78     }
  79   }
  80   return 1;  /* return table */
  81 }
  82
  83
  84 static int getlocal (lua_State *L) {
  85   lua_Debug ar;
  86   const char *name;
  87   if (!lua_getstack(L, luaL_check_int(L, 1), &ar))  /* level out of range? */
  88     luaL_argerror(L, 1, "level out of range");
  89   name = lua_getlocal(L, &ar, luaL_check_int(L, 2));
  90   if (name) {
  91     lua_pushstring(L, name);
  92     lua_pushvalue(L, -2);
  93     return 2;
  94   }
  95   else {
  96     lua_pushnil(L);
  97     return 1;
  98   }
  99 }
 100
 101
 102 static int setlocal (lua_State *L) {
 103   lua_Debug ar;
 104   if (!lua_getstack(L, luaL_check_int(L, 1), &ar))  /* level out of range? */
 105     luaL_argerror(L, 1, "level out of range");
 106   luaL_checkany(L, 3);
 107   lua_pushstring(L, lua_setlocal(L, &ar, luaL_check_int(L, 2)));
 108   return 1;
 109 }
 110
 111
 112
 113 /* dummy variables (to define unique addresses) */
 114 static char key1, key2;
 115 #define KEY_CALLHOOK    (&key1)
 116 #define KEY_LINEHOOK    (&key2)
 117
 118
 119 static void hookf (lua_State *L, void *key) {
 120   lua_getregistry(L);
 121   lua_pushuserdata(L, key);
 122   lua_gettable(L, -2);
 123   if (lua_isfunction(L, -1)) {
 124     lua_pushvalue(L, 1);
 125     lua_rawcall(L, 1, 0);
 126   }
 127   else
 128     lua_pop(L, 1);  /* pop result from gettable */
 129   lua_pop(L, 1);  /* pop table */
 130 }
 131
 132
 133 static void callf (lua_State *L, lua_Debug *ar) {
 134   lua_pushstring(L, ar->event);
 135   hookf(L, KEY_CALLHOOK);
 136 }
 137
 138
 139 static void linef (lua_State *L, lua_Debug *ar) {
 140   lua_pushnumber(L, ar->currentline);
 141   hookf(L, KEY_LINEHOOK);
 142 }
 143
 144
 145 static void sethook (lua_State *L, void *key, lua_Hook hook,
 146                      lua_Hook (*sethookf)(lua_State * L, lua_Hook h)) {
 147   lua_settop(L, 1);
 148   if (lua_isnil(L, 1))
 149     (*sethookf)(L, NULL);
 150   else if (lua_isfunction(L, 1))
 151     (*sethookf)(L, hook);
 152   else
 153     luaL_argerror(L, 1, "function expected");
 154   lua_getregistry(L);
 155   lua_pushuserdata(L, key);
 156   lua_pushvalue(L, -1);  /* dup key */
 157   lua_gettable(L, -3);   /* get old value */
 158   lua_pushvalue(L, -2);  /* key (again) */
 159   lua_pushvalue(L, 1);
 160   lua_settable(L, -5);  /* set new value */
 161 }
 162
 163
 164 static int setcallhook (lua_State *L) {
 165   sethook(L, KEY_CALLHOOK, callf, lua_setcallhook);
 166   return 1;
 167 }
 168
 169
 170 static int setlinehook (lua_State *L) {
 171   sethook(L, KEY_LINEHOOK, linef, lua_setlinehook);
 172   return 1;
 173 }
 174
 175
 176 static const struct luaL_reg dblib[] = {
 177   {"getlocal", getlocal},
 178   {"getinfo", getinfo},
 179   {"setcallhook", setcallhook},
 180   {"setlinehook", setlinehook},
 181   {"setlocal", setlocal}
 182 };
 183
 184
 185 LUALIB_API void lua_dblibopen (lua_State *L) {
 186   luaL_openl(L, dblib);
 187 }
 188