Cleanup server version updating

This commit is contained in:
Esa Korhonen
2018-11-19 16:10:10 +02:00
parent 0916b58c7e
commit 01628dd0de
8 changed files with 23 additions and 36 deletions

View File

@ -1092,13 +1092,11 @@ uint64_t server_map_status(const char* str)
*/
void server_set_version_string(SERVER* server, const char* version_string)
{
// There is a race here. The string may be accessed, while we are
// updating it. Thus we take some precautions to ensure that the
// string cannot be completely garbled at any point.
// Possible data race. The string may be accessed while we are updating it.
// Take some precautions to ensure that the string cannot be completely garbled at any point.
// Strictly speaking, this is not fool-proof as writes may not appear in order to the reader.
size_t old_len = strlen(server->version_string);
size_t new_len = strlen(version_string);
if (new_len >= MAX_SERVER_VERSION_LEN)
{
new_len = MAX_SERVER_VERSION_LEN - 1;
@ -1111,10 +1109,9 @@ void server_set_version_string(SERVER* server, const char* version_string)
memset(server->version_string + new_len, 0, old_len - new_len);
}
// No null-byte needs to be set. The array starts out as all zeros and the above memset adds
// the necessary null, should the new string be shorter than the old.
strncpy(server->version_string, version_string, new_len);
// No null-byte needs to be set. The array starts out as all zeros
// and the above memset adds the necessary null, should the new string
// be shorter than the old.
}
/**
@ -1128,8 +1125,9 @@ void server_set_version_string(SERVER* server, const char* version_string)
void server_set_version(SERVER* server, const char* version_string, uint64_t version)
{
server_set_version_string(server, version_string);
atomic_store_uint64(&server->version, version);
bool is_mariadb = (strcasestr(version_string, "mariadb") != NULL);
server->server_type = is_mariadb ? SERVER_TYPE_MARIADB : SERVER_TYPE_MYSQL;
}
uint64_t server_get_version(const SERVER* server)