int serialize_table_as_pb(lua_sandbox* lsb, int index)
{
output_data* d = &lsb->output;
d->pos = 0;
size_t needed = 18;
if (needed > d->size) {
if (realloc_output(d, needed)) return 1;
}
// create a type 4 uuid
d->data[d->pos++] = 2 | (1 << 3);
d->data[d->pos++] = 16;
for (int x = 0; x < 16; ++x) {
d->data[d->pos++] = rand() % 255;
}
d->data[8] = (d->data[8] & 0x0F) | 0x40;
d->data[10] = (d->data[10] & 0x0F) | 0xA0;
// use existing or create a timestamp
lua_getfield(lsb->lua, index, "Timestamp");
long long ts;
if (lua_isnumber(lsb->lua, -1)) {
ts = (long long)lua_tonumber(lsb->lua, -1);
} else {
ts = (long long)(time(NULL) * 1e9);
}
lua_pop(lsb->lua, 1);
if (pb_write_tag(d, 2, 0)) return 1;
if (pb_write_varint(d, ts)) return 1;
if (encode_string(lsb, d, 3, "Type", index)) return 1;
if (encode_string(lsb, d, 4, "Logger", index)) return 1;
if (encode_int(lsb, d, 5, "Severity", index)) return 1;
if (encode_string(lsb, d, 6, "Payload", index)) return 1;
if (encode_string(lsb, d, 7, "EnvVersion", index)) return 1;
if (encode_int(lsb, d, 8, "Pid", index)) return 1;
if (encode_string(lsb, d, 9, "Hostname", index)) return 1;
if (encode_fields(lsb, d, 10, "Fields", index)) return 1;
// if we go above 15 pb_write_tag will need to start varint encoding
needed = 1;
if (needed > d->size - d->pos) {
if (realloc_output(d, needed)) return 1;
}
d->data[d->pos] = 0; // NULL terminate incase someone tries to treat this
// as a string
return 0;
}
int appendc(output_data* output, char ch)
{
size_t needed = 2;
if (output->size - output->pos < needed) {
if (realloc_output(output, needed)) return 1;
}
output->data[output->pos++] = ch;
output->data[output->pos] = 0;
return 0;
}
int appends(output_data* output, const char* str)
{
size_t needed = strlen(str) + 1;
if (output->size - output->pos < needed) {
if (realloc_output(output, needed)) return 1;
}
memcpy(output->data + output->pos, str, needed);
output->pos += needed - 1;
return 0;
}
int pb_write_tag(output_data* d, char id, char wire_type)
{
size_t needed = 1;
if (needed > d->size - d->pos) {
if (realloc_output(d, needed)) return 1;
}
d->data[d->pos++] = wire_type | (id << 3);
return 0;
}
int pb_write_double(output_data* d, double i)
{
size_t needed = sizeof(double);
if (needed > d->size - d->pos) {
if (realloc_output(d, needed)) return 1;
}
memcpy(&d->data[d->pos], &i, needed);
d->pos += needed;
return 0;
}
int pb_write_bool(output_data* d, int i)
{
size_t needed = 1;
if (needed > d->size - d->pos) {
if (realloc_output(d, needed)) return 1;
}
if (i) {
d->data[d->pos++] = 1;
} else {
d->data[d->pos++] = 0;
}
return 0;
}
int pb_write_string(output_data* d, char id, const char* s, size_t len)
{
if (pb_write_tag(d, id, 2)) return 1;
if (pb_write_varint(d, len)) return 1;
size_t needed = len;
if (needed > d->m_size - d->m_pos) {
if (realloc_output(d, needed)) return 1;
}
memcpy(&d->m_data[d->m_pos], s, len);
d->m_pos += len;
return 0;
}
int pb_write_varint(output_data* d, long long i)
{
size_t needed = 10;
if (needed > d->size - d->pos) {
if (realloc_output(d, needed)) return 1;
}
if (i == 0) {
d->data[d->pos++] = 0;
return 0;
}
while (i) {
d->data[d->pos++] = (i & 0x7F) | 0x80;
i >>= 7;
}
d->data[d->pos - 1] &= 0x7F; // end the varint
return 0;
}
int update_field_length(output_data* d, size_t len_pos)
{
size_t len = d->pos - len_pos - 1;
if (len < 128) {
d->data[len_pos] = (char)len;
return 0;
}
size_t l = len, cnt = 0;
while (l) {
l >>= 7;
++cnt; // compute the number of bytes needed for the varint length
}
size_t needed = cnt - 1;
if (needed > d->size - d->pos) {
if (realloc_output(d, needed)) return 1;
}
size_t end_pos = d->pos + needed;
memmove(&d->data[len_pos + cnt], &d->data[len_pos + 1], len);
d->pos = len_pos;
if (pb_write_varint(d, len)) return 1;
d->pos = end_pos;
return 0;
}
int serialize_data_as_json(lua_sandbox* lsb, int index, output_data* output)
{
const char* s;
size_t len = 0;
size_t start_pos = output->pos;
size_t escaped_len = 0;
switch (lua_type(lsb->lua, index)) {
case LUA_TNUMBER:
if (serialize_double(output, lua_tonumber(lsb->lua, index))) {
return 1;
}
break;
case LUA_TSTRING:
s = lua_tolstring(lsb->lua, index, &len);
escaped_len = len + 3; // account for the quotes and terminator
if (output->pos + escaped_len > output->size) {
if (realloc_output(output, escaped_len)) return 1;
}
output->data[output->pos++] = '"';
for (size_t i = 0; i < len; ++i) {
// buffer needs at least enough room for an escaped character, an end
// quote and a null terminator
if (output->pos + 4 > output->size) {
size_t needed = escaped_len - (output->pos - start_pos);
if (realloc_output(output, needed)) return 1;
}
switch (s[i]) {
case '"':
output->data[output->pos++] = '\\';
output->data[output->pos++] = '"';
++escaped_len;
break;
case '\\':
output->data[output->pos++] = '\\';
output->data[output->pos++] = '\\';
++escaped_len;
break;
case '/':
output->data[output->pos++] = '\\';
output->data[output->pos++] = '/';
++escaped_len;
break;
case '\b':
output->data[output->pos++] = '\\';
output->data[output->pos++] = 'b';
++escaped_len;
break;
case '\f':
output->data[output->pos++] = '\\';
output->data[output->pos++] = 'f';
++escaped_len;
break;
case '\n':
output->data[output->pos++] = '\\';
output->data[output->pos++] = 'n';
++escaped_len;
break;
case '\r':
output->data[output->pos++] = '\\';
output->data[output->pos++] = 'r';
++escaped_len;
break;
case '\t':
output->data[output->pos++] = '\\';
output->data[output->pos++] = 't';
++escaped_len;
break;
default:
output->data[output->pos++] = s[i];
}
}
output->data[output->pos++] = '"';
output->data[output->pos] = 0;
break;
case LUA_TBOOLEAN:
if (appendf(output, "%s", lua_toboolean(lsb->lua, index)
? "true" : "false")) {
return 1;
}
case LUA_TNIL:
break;
default:
snprintf(lsb->error_message, LSB_ERROR_SIZE,
"serialize_data_as_json cannot preserve type '%s'",
lua_typename(lsb->lua, lua_type(lsb->lua, index)));
return 1;
}
return 0;
}