/**
* Iterates over the specified Lua table encoding the contents as user defined
* message fields.
*
* @param lsb Pointer to the sandbox.
* @param ob Pointer to the output data buffer.
* @param tag Field identifier.
* @param name Key used for the Lua table entry lookup.
* @param index Lua stack index of the table.
*
* @return lsb_err_value NULL on success error message on failure
*/
static lsb_err_value
encode_fields(lsb_lua_sandbox *lsb, lsb_output_buffer *ob, char tag,
const char *name, int index)
{
lsb_err_value ret = NULL;
lua_getfield(lsb->lua, index, name);
if (!lua_istable(lsb->lua, -1)) {
return ret;
}
lua_rawgeti(lsb->lua, -1, 1); // test for the array notation
size_t len_pos, len;
if (lua_istable(lsb->lua, -1)) {
int i = 1;
do {
ret = lsb_pb_write_key(ob, tag, LSB_PB_WT_LENGTH);
if (ret) return ret;
len_pos = ob->pos;
ret = lsb_pb_write_varint(ob, 0); // length tbd later
if (ret) return ret;
lua_getfield(lsb->lua, -1, "name");
if (lua_isstring(lsb->lua, -1)) {
const char *s = lua_tolstring(lsb->lua, -1, &len);
ret = lsb_pb_write_string(ob, LSB_PB_NAME, s, len);
} else {
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"field name must be a string");
ret = LSB_ERR_HEKA_INPUT;
}
lua_pop(lsb->lua, 1); // remove the name
if (ret) return ret;
ret = encode_field_object(lsb, ob);
if (!ret) ret = lsb_pb_update_field_length(ob, len_pos);
if (ret) return ret;
lua_pop(lsb->lua, 1); // remove the current field object
lua_rawgeti(lsb->lua, -1, ++i); // grab the next field object
} while (!ret && !lua_isnil(lsb->lua, -1));
} else {
lua_pop(lsb->lua, 1); // remove the array test value
lua_checkstack(lsb->lua, 2);
lua_pushnil(lsb->lua);
while (lua_next(lsb->lua, -2) != 0) {
ret = lsb_pb_write_key(ob, tag, LSB_PB_WT_LENGTH);
if (ret) return ret;
len_pos = ob->pos;
ret = lsb_pb_write_varint(ob, 0); // length tbd later
if (ret) return ret;
if (lua_isstring(lsb->lua, -2)) {
const char *s = lua_tolstring(lsb->lua, -2, &len);
ret = lsb_pb_write_string(ob, LSB_PB_NAME, s, len);
} else {
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"field name must be a string");
ret = LSB_ERR_HEKA_INPUT;
}
if (ret) return ret;
ret = encode_field_value(lsb, ob, 1, NULL, -1);
if (!ret) ret = lsb_pb_update_field_length(ob, len_pos);
if (ret) return ret;
lua_pop(lsb->lua, 1); // Remove the value leaving the key on top for
// the next interation.
}
}
lua_pop(lsb->lua, 1); // remove the fields table
return ret;
}
int encode_field_value(lua_sandbox* lsb, output_data* d, int first,
const char* representation)
{
int result = 1;
size_t len;
const char* s;
int t = lua_type(lsb->lua, -1);
switch (t) {
case LUA_TSTRING:
if (first && representation) { // this uglyness keeps the protobuf
// fields in order without additional
// lookups
if (pb_write_string(d, 3, representation, strlen(representation))) {
return 1;
}
}
s = lua_tolstring(lsb->lua, -1, &len);
result = pb_write_string(d, 4, s, len);
break;
case LUA_TNUMBER:
if (first) {
if (pb_write_tag(d, 2, 0)) return 1;
if (pb_write_varint(d, 3)) return 1;
if (representation) {
if (pb_write_string(d, 3, representation,
strlen(representation))) {
return 1;
}
}
}
result = encode_double(lsb, d, 7);
break;
case LUA_TBOOLEAN:
if (first) {
if (pb_write_tag(d, 2, 0)) return 1;
if (pb_write_varint(d, 4)) return 1;
if (representation) {
if (pb_write_string(d, 3, representation,
strlen(representation))) {
return 1;
}
}
}
if (pb_write_tag(d, 8, 0)) return 1;
result = pb_write_bool(d, lua_toboolean(lsb->lua, -1));
break;
case LUA_TTABLE:
{
lua_rawgeti(lsb->lua, -1, 1);
int t = lua_type(lsb->lua, -1);
lua_pop(lsb->lua, 1); // remove the array test value
if (LUA_TNIL == t) {
result = encode_field_object(lsb, d);
} else {
result = encode_field_array(lsb, d, t, representation);
}
}
break;
default:
snprintf(lsb->error_message, LSB_ERROR_SIZE, "unsupported type %d", t);
result = 1;
}
return result;
}
static lsb_err_value
encode_field_value(lsb_lua_sandbox *lsb, lsb_output_buffer *ob, int first,
const char *representation, int value_type)
{
lsb_err_value ret = NULL;
size_t len;
const char *s;
int t = lua_type(lsb->lua, -1);
switch (t) {
case LUA_TSTRING:
switch (value_type) {
case -1: // not specified defaults to string
value_type = 0;
case 0:
case 1:
break;
default:
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"invalid string value_type: %d", value_type);
return LSB_ERR_HEKA_INPUT;
}
if (first) { // this uglyness keeps the protobuf fields in order without
// additional lookups
if (value_type == LSB_PB_BYTES) {
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_TYPE, LSB_PB_WT_VARINT);
if (!ret) ret = lsb_pb_write_varint(ob, value_type);
if (ret) return ret;
}
if (representation) {
ret = lsb_pb_write_string(ob, LSB_PB_REPRESENTATION, representation,
strlen(representation));
if (ret) return ret;
}
}
s = lua_tolstring(lsb->lua, -1, &len);
if (value_type == LSB_PB_BYTES) {
ret = lsb_pb_write_string(ob, LSB_PB_VALUE_BYTES, s, len);
if (ret) return ret;
} else {
ret = lsb_pb_write_string(ob, LSB_PB_VALUE_STRING, s, len);
if (ret) return ret;
}
break;
case LUA_TNUMBER:
switch (value_type) {
case -1: // not specified defaults to double
value_type = 3;
case 2:
case 3:
break;
default:
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"invalid numeric value_type: %d", value_type);
return LSB_ERR_HEKA_INPUT;
}
if (first) {
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_TYPE, LSB_PB_WT_VARINT);
if (!ret) ret = lsb_pb_write_varint(ob, value_type);
if (ret) return ret;
if (representation) {
ret = lsb_pb_write_string(ob, LSB_PB_REPRESENTATION, representation,
strlen(representation));
if (ret) return ret;
}
if (1 == first) {
if (value_type == LSB_PB_INTEGER) {
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_INTEGER, LSB_PB_WT_VARINT);
} else {
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_DOUBLE, LSB_PB_WT_FIXED64);
}
if (ret) return ret;
} else { // pack array
if (value_type == LSB_PB_INTEGER) {
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_INTEGER, LSB_PB_WT_LENGTH);
if (!ret) ret = lsb_pb_write_varint(ob, 0); // length tbd later
} else {
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_DOUBLE, LSB_PB_WT_LENGTH);
if (!ret) ret = lsb_pb_write_varint(ob, first * sizeof(double));
}
if (ret) return ret;
}
}
if (value_type == LSB_PB_INTEGER) {
ret = lsb_pb_write_varint(ob, lua_tointeger(lsb->lua, -1));
} else {
ret = lsb_pb_write_double(ob, lua_tonumber(lsb->lua, -1));
}
if (ret) return ret;
break;
case LUA_TBOOLEAN:
if (value_type != -1 && value_type != LSB_PB_BOOL) {
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"invalid boolean value_type: %d", value_type);
return LSB_ERR_HEKA_INPUT;
}
if (first) {
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_TYPE, LSB_PB_WT_VARINT);
if (!ret) ret = lsb_pb_write_varint(ob, LSB_PB_BOOL);
if (ret) return ret;
if (representation) {
ret = lsb_pb_write_string(ob, LSB_PB_REPRESENTATION, representation,
strlen(representation));
if (ret) return ret;
}
if (1 == first) {
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_BOOL, LSB_PB_WT_VARINT);
} else {
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_BOOL, LSB_PB_WT_LENGTH);
if (!ret) ret = lsb_pb_write_varint(ob, first);
}
if (ret) return ret;
}
ret = lsb_pb_write_bool(ob, lua_toboolean(lsb->lua, -1));
break;
case LUA_TTABLE:
{
lua_rawgeti(lsb->lua, -1, 1);
int t = lua_type(lsb->lua, -1);
lua_pop(lsb->lua, 1); // remove the array test value
switch (t) {
case LUA_TNIL:
ret = encode_field_object(lsb, ob);
break;
case LUA_TNUMBER:
case LUA_TSTRING:
case LUA_TBOOLEAN:
ret = encode_field_array(lsb, ob, t, representation, value_type);
break;
default:
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"unsupported array type: %s", lua_typename(lsb->lua, t));
return LSB_ERR_LUA;
}
}
break;
case LUA_TLIGHTUSERDATA:
lua_getfield(lsb->lua, -4, "userdata");
if (lua_type(lsb->lua, -1) != LUA_TUSERDATA) {
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"a lightuserdata output must also specify a userdata value");
return LSB_ERR_LUA;
}
// fall thru
case LUA_TUSERDATA:
{
lua_CFunction fp = lsb_get_output_function(lsb->lua, -1);
size_t len_pos = 0;
if (!fp) {
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"userdata object does not implement lsb_output");
return LSB_ERR_LUA;
}
if (first) {
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_TYPE, LSB_PB_WT_VARINT);
if (ret) return ret;
// encode userdata as a byte array
ret = lsb_pb_write_varint(ob, LSB_PB_BYTES);
if (ret) return ret;
if (representation) {
ret = lsb_pb_write_string(ob, LSB_PB_REPRESENTATION, representation,
strlen(representation));
if (ret) return ret;
}
}
ret = lsb_pb_write_key(ob, LSB_PB_VALUE_BYTES, LSB_PB_WT_LENGTH);
if (ret) return ret;
len_pos = ob->pos;
ret = lsb_pb_write_varint(ob, 0); // length tbd later
if (ret) return ret;
lua_pushlightuserdata(lsb->lua, ob);
int result = fp(lsb->lua);
lua_pop(lsb->lua, 1); // remove output function
if (result) {
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"userdata output callback failed: %d", result);
return LSB_ERR_LUA;
}
ret = lsb_pb_update_field_length(ob, len_pos);
}
if (t == LUA_TLIGHTUSERDATA) lua_pop(lsb->lua, 1); // remove the userdata
break;
default:
snprintf(lsb->error_message, LSB_ERROR_SIZE, "unsupported type: %s",
lua_typename(lsb->lua, t));
return LSB_ERR_LUA;
}
return ret;
}