lua/luadb.c

   1 #include "lua.h"
   2 #include "luabot.h"
   3 #include "../pqsql/pqsql.h"
   4
   5 static int lua_dbcreatequery(lua_State *ps) {
   6   char *s = (char *)lua_tostring(ps, 1);
   7
   8   if(!s)
   9     LUA_RETURN(ps, LUA_FAIL);
  10
  11   pqcreatequery(s);
  12   LUA_RETURN(ps, LUA_OK);
  13 }
  14
  15 /* TODO */
  16 /*
  17 static int lua_dbloadtable(lua_State *ps) {
  18   lua_list *l = lua_listfromstate(ps);
  19   if(!l)
  20     LUA_RETURN(ps, LUA_FAIL);
  21
  22 }
  23 */
  24
  25 typedef struct lua_callback {
  26   lua_list *l;
  27   long handler, args;
  28 } lua_callback;
  29
  30 /* hack */
  31 PGresult *pgres;
  32
  33 static int lua_dbnumfields(lua_State *ps) {
  34   lua_pushint(ps, PQnfields(pgres));
  35
  36   return 1;
  37 }
  38
  39 static int lua_dbnumrows(lua_State *ps) {
  40   lua_pushint(ps, PQntuples(pgres));
  41
  42   return 1;
  43 }
  44
  45 static int lua_dbgetvalue(lua_State *ps) {
  46   char *r;
  47   int tuple, field, len;
  48
  49   if(!lua_isint(ps, 1) || !lua_isint(ps, 2))
  50     return 0;
  51
  52   tuple = lua_toint(ps, 1);
  53   field = lua_toint(ps, 2);
  54
  55   r = PQgetvalue(pgres, lua_toint(ps, 1), lua_toint(ps, 2));
  56   len = PQgetlength(pgres, tuple, field);
  57
  58   lua_pushlstring(ps, r, len); /* safe?! */
  59
  60   return 1;
  61 }
  62
  63 void lua_dbcallback(PGconn *dbconn, void *arg) {
  64   pgres = PQgetResult(dbconn);
  65   lua_callback *c = (lua_callback *)arg;
  66
  67   if(!lua_listexists(c->l)) {
  68     luafree(c);
  69     return;
  70   }
  71
  72   if(PQresultStatus(pgres) != PGRES_TUPLES_OK) {
  73     _lua_vpcall(c->l->l, (void *)c->handler, LUA_POINTERMODE, "bR", 0, c->args);
  74
  75     luaL_unref(c->l->l, LUA_REGISTRYINDEX, c->handler);
  76     luaL_unref(c->l->l, LUA_REGISTRYINDEX, c->args);
  77     luafree(c);
  78     return;
  79   }
  80
  81   _lua_vpcall(c->l->l, (void *)c->handler, LUA_POINTERMODE, "bR", 1, c->args);
  82
  83   luaL_unref(c->l->l, LUA_REGISTRYINDEX, c->handler);
  84   luaL_unref(c->l->l, LUA_REGISTRYINDEX, c->args);
  85   luafree(c);
  86   PQclear(pgres);
  87   pgres = NULL;
  88 }
  89
  90 static int lua_dbquery(lua_State *ps) {
  91   lua_list *l = lua_listfromstate(ps);
  92   char *q = (char *)lua_tostring(ps, 1);
  93   lua_callback *cb;
  94
  95   /* what happens if 3 isn't there? */
  96   if(!l || !q)
  97     LUA_RETURN(ps, LUA_FAIL);
  98
  99   if(!lua_isfunction(ps, 2)) {
 100     pqquery(q);
 101     LUA_RETURN(ps, LUA_OK);
 102   }
 103
 104   cb = (lua_callback *)luamalloc(sizeof(lua_callback));
 105   if(!cb)
 106     LUA_RETURN(ps, LUA_FAIL);
 107
 108   cb->l = l;
 109   cb->args = luaL_ref(ps, LUA_REGISTRYINDEX);
 110   cb->handler = luaL_ref(ps, LUA_REGISTRYINDEX);
 111
 112   pqasyncquery(lua_dbcallback, cb, q);
 113
 114   LUA_RETURN(ps, LUA_OK);
 115 }
 116
 117 static int lua_dbescape(lua_State *ps) {
 118   char ebuf[8192 * 2];
 119   char *s = (char *)lua_tostring(ps, 1);
 120   int len;
 121   size_t elen;
 122
 123   if(!s)
 124     return 0;
 125
 126   len = lua_strlen(ps, 1);
 127   if(len > sizeof(ebuf) / 2 - 5)
 128     return 0;
 129
 130   elen = PQescapeString(ebuf, s, len);
 131   lua_pushlstring(ps, ebuf, elen);
 132
 133   return 1;
 134 }
 135
 136 void lua_registerdbcommands(lua_State *l) {
 137   lua_register(l, "db_createquery", lua_dbcreatequery);
 138
 139 /*   lua_register(l, "db_loadtable", lua_dbloadtable); */
 140
 141   lua_register(l, "db_query", lua_dbquery);
 142   lua_register(l, "db_escape", lua_dbescape);
 143   lua_register(l, "db_numfields", lua_dbnumfields);
 144   lua_register(l, "db_numrows", lua_dbnumrows);
 145   lua_register(l, "db_getvalue", lua_dbgetvalue);
 146 }