int encode_field_array(lua_sandbox* lsb, output_data* d, int t,
const char* representation)
{
int result = 0, first = 1;
lua_checkstack(lsb->m_lua, 2);
lua_pushnil(lsb->m_lua);
while (result == 0 && lua_next(lsb->m_lua, -2) != 0) {
// numerics are not packed, the space savings aren't worth the extra
// buffer manipulation
if (lua_type(lsb->m_lua, -1) != t) {
snprintf(lsb->m_error_message, ERROR_SIZE, "array has mixed types");
return 1;
}
result = encode_field_value(lsb, d, first, representation);
first = 0;
lua_pop(lsb->m_lua, 1); // Remove the value leaving the key on top for
// the next interation.
}
return result;
}
/**
* Encodes a field that contains metadata in addition to its value.
*
* @param lsb Pointer to the sandbox.
* @param ob Pointer to the output data buffer.
*
* @return lsb_err_value NULL on success error message on failure
*/
static lsb_err_value
encode_field_object(lsb_lua_sandbox *lsb, lsb_output_buffer *ob)
{
const char *representation = NULL;
lua_getfield(lsb->lua, -1, "representation");
if (lua_isstring(lsb->lua, -1)) {
representation = lua_tostring(lsb->lua, -1);
}
int value_type = -1;
lua_getfield(lsb->lua, -2, "value_type");
if (lua_isnumber(lsb->lua, -1)) {
value_type = (int)lua_tointeger(lsb->lua, -1);
}
lua_getfield(lsb->lua, -3, "value");
lsb_err_value ret = encode_field_value(lsb, ob, 1, representation, value_type);
lua_pop(lsb->lua, 3); // remove representation, value_type and value
return ret;
}
/**
* Encodes a field that has an array of values.
*
* @param lsb Pointer to the sandbox.
* @param ob Pointer to the output data buffer.
* @param t Lua type of the array values.
* @param representation String representation of the field i.e., "ms"
*
* @return lsb_err_value NULL on success error message on failure
*/
static lsb_err_value
encode_field_array(lsb_lua_sandbox *lsb, lsb_output_buffer *ob, int t,
const char *representation, int value_type)
{
lsb_err_value ret = NULL;
int first = (int)lua_objlen(lsb->lua, -1);
int multiple = first > 1 ? first : 0;
size_t len_pos = 0;
lua_checkstack(lsb->lua, 2);
lua_pushnil(lsb->lua);
while (!ret && lua_next(lsb->lua, -2) != 0) {
if (lua_type(lsb->lua, -1) != t) {
snprintf(lsb->error_message, LSB_ERROR_SIZE, "array has mixed types");
return LSB_ERR_HEKA_INPUT;
}
ret = encode_field_value(lsb, ob, first, representation, value_type);
if (first) {
len_pos = ob->pos;
first = 0;
}
lua_pop(lsb->lua, 1); // Remove the value leaving the key on top for
// the next interation.
}
if (!ret && multiple && value_type == LSB_PB_INTEGER) {
// fix up the varint packed length
size_t i = len_pos - 2;
int y = 0;
// find the length byte
while (ob->buf[i] != 0 && y < LSB_MAX_VARINT_BYTES) {
--i;
++y;
}
if (y == LSB_MAX_VARINT_BYTES) {
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"unable set the length of the packed integer array");
return LSB_ERR_LUA;
}
ret = lsb_pb_update_field_length(ob, i);
}
return ret;
}
/**
* 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;
}