1 files changed, 345 insertions, 0 deletions
diff --git a/src/ldblib.c b/src/ldblib.c
new file mode 100644
index 00000000..36d647aa
--- /dev/null
+++ b/src/ldblib.c
@@ -0,0 +1,345 @@
+/*
+** $Id: ldblib.c,v 1.89 2004/11/17 12:02:41 roberto Exp $
+** Interface from Lua to its debug API
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ldblib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+
+static void settabss (lua_State *L, const char *i, const char *v) {
+  lua_pushstring(L, v);
+  lua_setfield(L, -2, i);
+}
+
+
+static void settabsi (lua_State *L, const char *i, int v) {
+  lua_pushinteger(L, v);
+  lua_setfield(L, -2, i);
+}
+
+
+static lua_State *getthread (lua_State *L, int *arg) {
+  if (lua_isthread(L, 1)) {
+    *arg = 1;
+    return lua_tothread(L, 1);
+  }
+  else {
+    *arg = 0;
+    return L;
+  }
+}
+
+
+static int getinfo (lua_State *L) {
+  lua_Debug ar;
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  const char *options = luaL_optstring(L, arg+2, "flnSu");
+  if (lua_isnumber(L, arg+1)) {
+    if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), &ar)) {
+      lua_pushnil(L);  /* level out of range */
+      return 1;
+    }
+  }
+  else if (lua_isfunction(L, arg+1)) {
+    lua_pushfstring(L, ">%s", options);
+    options = lua_tostring(L, -1);
+    lua_pushvalue(L, arg+1);
+    lua_xmove(L, L1, 1);
+  }
+  else
+    return luaL_argerror(L, arg+1, "function or level expected");
+  if (!lua_getinfo(L1, options, &ar))
+    return luaL_argerror(L, arg+2, "invalid option");
+  lua_newtable(L);
+  for (; *options; options++) {
+    switch (*options) {
+      case 'S':
+        settabss(L, "source", ar.source);
+        settabss(L, "short_src", ar.short_src);
+        settabsi(L, "linedefined", ar.linedefined);
+        settabss(L, "what", ar.what);
+        break;
+      case 'l':
+        settabsi(L, "currentline", ar.currentline);
+        break;
+      case 'u':
+        settabsi(L, "nups", ar.nups);
+        break;
+      case 'n':
+        settabss(L, "name", ar.name);
+        settabss(L, "namewhat", ar.namewhat);
+        break;
+      case 'f':
+        if (L == L1)
+          lua_pushvalue(L, -2);
+        else
+          lua_xmove(L1, L, 1);
+        lua_setfield(L, -2, "func");
+        break;
+    }
+  }
+  return 1;  /* return table */
+}
+    
+
+static int getlocal (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  const char *name;
+  if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
+    return luaL_argerror(L, arg+1, "level out of range");
+  name = lua_getlocal(L1, &ar, luaL_checkint(L, arg+2));
+  if (name) {
+    lua_xmove(L1, L, 1);
+    lua_pushstring(L, name);
+    lua_pushvalue(L, -2);
+    return 2;
+  }
+  else {
+    lua_pushnil(L);
+    return 1;
+  }
+}
+
+
+static int setlocal (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
+    return luaL_argerror(L, arg+1, "level out of range");
+  luaL_checkany(L, arg+3);
+  lua_settop(L, arg+3);
+  lua_xmove(L, L1, 1);
+  lua_pushstring(L, lua_setlocal(L1, &ar, luaL_checkint(L, arg+2)));
+  return 1;
+}
+
+
+static int auxupvalue (lua_State *L, int get) {
+  const char *name;
+  int n = luaL_checkint(L, 2);
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  if (lua_iscfunction(L, 1)) return 0;  /* cannot touch C upvalues from Lua */
+  name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
+  if (name == NULL) return 0;
+  lua_pushstring(L, name);
+  lua_insert(L, -(get+1));
+  return get + 1;
+}
+
+
+static int getupvalue (lua_State *L) {
+  return auxupvalue(L, 1);
+}
+
+
+static int setupvalue (lua_State *L) {
+  luaL_checkany(L, 3);
+  return auxupvalue(L, 0);
+}
+
+
+
+static const char KEY_HOOK = 'h';
+
+
+static void hookf (lua_State *L, lua_Debug *ar) {
+  static const char *const hooknames[] =
+    {"call", "return", "line", "count", "tail return"};
+  lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+  lua_rawget(L, LUA_REGISTRYINDEX);
+  lua_pushlightuserdata(L, L);
+  lua_rawget(L, -2);
+  if (lua_isfunction(L, -1)) {
+    lua_pushstring(L, hooknames[(int)ar->event]);
+    if (ar->currentline >= 0)
+      lua_pushinteger(L, ar->currentline);
+    else lua_pushnil(L);
+    lua_assert(lua_getinfo(L, "lS", ar));
+    lua_call(L, 2, 0);
+  }
+}
+
+
+static int makemask (const char *smask, int count) {
+  int mask = 0;
+  if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
+  if (strchr(smask, 'r')) mask |= LUA_MASKRET;
+  if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
+  if (count > 0) mask |= LUA_MASKCOUNT;
+  return mask;
+}
+
+
+static char *unmakemask (int mask, char *smask) {
+  int i = 0;
+  if (mask & LUA_MASKCALL) smask[i++] = 'c';
+  if (mask & LUA_MASKRET) smask[i++] = 'r';
+  if (mask & LUA_MASKLINE) smask[i++] = 'l';
+  smask[i] = '\0';
+  return smask;
+}
+
+
+static void gethooktable (lua_State *L) {
+  lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+  lua_rawget(L, LUA_REGISTRYINDEX);
+  if (!lua_istable(L, -1)) {
+    lua_pop(L, 1);
+    lua_newtable(L);
+    lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+    lua_pushvalue(L, -2);
+    lua_rawset(L, LUA_REGISTRYINDEX);
+  }
+}
+
+
+static int sethook (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  if (lua_isnoneornil(L, arg+1)) {
+    lua_settop(L, arg+1);
+    lua_sethook(L1, NULL, 0, 0);  /* turn off hooks */
+  }
+  else {
+    const char *smask = luaL_checkstring(L, arg+2);
+    int count = luaL_optint(L, arg+3, 0);
+    luaL_checktype(L, arg+1, LUA_TFUNCTION);
+    lua_sethook(L1, hookf, makemask(smask, count), count);
+  }
+  gethooktable(L1);
+  lua_pushlightuserdata(L1, L1);
+  lua_pushvalue(L, arg+1);
+  lua_xmove(L, L1, 1);
+  lua_rawset(L1, -3);  /* set new hook */
+  lua_pop(L1, 1);  /* remove hook table */
+  return 0;
+}
+
+
+static int gethook (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  char buff[5];
+  int mask = lua_gethookmask(L1);
+  lua_Hook hook = lua_gethook(L1);
+  if (hook != NULL && hook != hookf)  /* external hook? */
+    lua_pushliteral(L, "external hook");
+  else {
+    gethooktable(L1);
+    lua_pushlightuserdata(L1, L1);
+    lua_rawget(L1, -2);   /* get hook */
+    lua_remove(L1, -2);  /* remove hook table */
+    lua_xmove(L1, L, 1);
+  }
+  lua_pushstring(L, unmakemask(mask, buff));
+  lua_pushinteger(L, lua_gethookcount(L1));
+  return 3;
+}
+
+
+static int debug (lua_State *L) {
+  for (;;) {
+    char buffer[250];
+    fputs("lua_debug> ", stderr);
+    if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
+        strcmp(buffer, "cont\n") == 0)
+      return 0;
+    if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||
+        lua_pcall(L, 0, 0, 0)) {
+      fputs(lua_tostring(L, -1), stderr);
+      fputs("\n", stderr);
+    }
+    lua_settop(L, 0);  /* remove eventual returns */
+  }
+}
+
+
+#define LEVELS1	12	/* size of the first part of the stack */
+#define LEVELS2	10	/* size of the second part of the stack */
+
+static int errorfb (lua_State *L) {
+  int level = 0;
+  int firstpart = 1;  /* still before eventual `...' */
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  if (L == L1) level++;  /* skip level 0 (it's this function) */
+  if (lua_gettop(L) == arg)
+    lua_pushliteral(L, "");
+  else if (!lua_isstring(L, arg+1)) return 1;  /* message is not a string */
+  else lua_pushliteral(L, "\n");
+  lua_pushliteral(L, "stack traceback:");
+  while (lua_getstack(L1, level++, &ar)) {
+    if (level > LEVELS1 && firstpart) {
+      /* no more than `LEVELS2' more levels? */
+      if (!lua_getstack(L1, level+LEVELS2, &ar))
+        level--;  /* keep going */
+      else {
+        lua_pushliteral(L, "\n\t...");  /* too many levels */
+        while (lua_getstack(L1, level+LEVELS2, &ar))  /* find last levels */
+          level++;
+      }
+      firstpart = 0;
+      continue;
+    }
+    lua_pushliteral(L, "\n\t");
+    lua_getinfo(L1, "Snl", &ar);
+    lua_pushfstring(L, "%s:", ar.short_src);
+    if (ar.currentline > 0)
+      lua_pushfstring(L, "%d:", ar.currentline);
+    if (*ar.namewhat != '\0')  /* is there a name? */
+        lua_pushfstring(L, " in function `%s'", ar.name);
+    else {
+      if (*ar.what == 'm')  /* main? */
+        lua_pushfstring(L, " in main chunk");
+      else if (*ar.what == 'C' || *ar.what == 't')
+        lua_pushliteral(L, " ?");  /* C function or tail call */
+      else
+        lua_pushfstring(L, " in function <%s:%d>",
+                           ar.short_src, ar.linedefined);
+    }
+    lua_concat(L, lua_gettop(L) - arg);
+  }
+  lua_concat(L, lua_gettop(L) - arg);
+  return 1;
+}
+
+
+static const luaL_reg dblib[] = {
+  {"getlocal", getlocal},
+  {"getinfo", getinfo},
+  {"gethook", gethook},
+  {"getupvalue", getupvalue},
+  {"sethook", sethook},
+  {"setlocal", setlocal},
+  {"setupvalue", setupvalue},
+  {"debug", debug},
+  {"traceback", errorfb},
+  {NULL, NULL}
+};
+
+
+LUALIB_API int luaopen_debug (lua_State *L) {
+  luaL_openlib(L, LUA_DBLIBNAME, dblib, 0);
+  lua_pushcfunction(L, errorfb);
+  lua_setglobal(L, "_TRACEBACK");
+  return 1;
+}
+