diff options
author | dec05eba <dec05eba@protonmail.com> | 2024-05-13 21:22:29 +0200 |
---|---|---|
committer | dec05eba <dec05eba@protonmail.com> | 2024-05-13 21:22:29 +0200 |
commit | c01eb535136a0f4b2545a8a8df0d9b3c527cd02f (patch) | |
tree | 8da3ac4152efbbae5b56045cd600a5ab8e22d609 /kms/client/kms_client.c | |
parent | 133c3a22b9cf3a55ebda19ce2af6db2e236462f1 (diff) |
fix possible freeze on exit if exiting quickly after start
Diffstat (limited to 'kms/client/kms_client.c')
-rw-r--r-- | kms/client/kms_client.c | 29 |
1 files changed, 22 insertions, 7 deletions
diff --git a/kms/client/kms_client.c b/kms/client/kms_client.c index 1c8f634..869bf81 100644 --- a/kms/client/kms_client.c +++ b/kms/client/kms_client.c @@ -79,7 +79,7 @@ static int send_msg_to_server(int server_fd, gsr_kms_request *request) { return sendmsg(server_fd, &response_message, 0); } -static int recv_msg_from_server(int server_fd, gsr_kms_response *response) { +static int recv_msg_from_server(int server_pid, int server_fd, gsr_kms_response *response) { struct iovec iov; iov.iov_base = response; iov.iov_len = sizeof(*response); @@ -93,11 +93,26 @@ static int recv_msg_from_server(int server_fd, gsr_kms_response *response) { response_message.msg_control = cmsgbuf; response_message.msg_controllen = sizeof(cmsgbuf); - int res = recvmsg(server_fd, &response_message, MSG_WAITALL); - if(res <= 0) - return res; + int res = 0; + for(;;) { + res = recvmsg(server_fd, &response_message, MSG_DONTWAIT); + if(res <= 0 && (errno == EAGAIN || errno == EWOULDBLOCK)) { + // If we are replacing the connection and closing the application at the same time + // then recvmsg can get stuck (because the server died), so we prevent that by doing + // non-blocking recvmsg and checking if the server died + int status = 0; + int wait_result = waitpid(server_pid, &status, WNOHANG); + if(wait_result != 0) { + res = -1; + break; + } + usleep(1000); + } else { + break; + } + } - if(response->num_fds > 0) { + if(res > 0 && response->num_fds > 0) { struct cmsghdr *cmsg = CMSG_FIRSTHDR(&response_message); if(cmsg) { int *fds = (int*)CMSG_DATA(cmsg); @@ -371,7 +386,7 @@ int gsr_kms_client_replace_connection(gsr_kms_client *self) { return -1; } - const int recv_res = recv_msg_from_server(self->socket_pair[GSR_SOCKET_PAIR_LOCAL], &response); + const int recv_res = recv_msg_from_server(self->kms_server_pid, self->socket_pair[GSR_SOCKET_PAIR_LOCAL], &response); if(recv_res == 0) { fprintf(stderr, "gsr warning: gsr_kms_client_replace_connection: kms server shut down\n"); return -1; @@ -404,7 +419,7 @@ int gsr_kms_client_get_kms(gsr_kms_client *self, gsr_kms_response *response) { return -1; } - const int recv_res = recv_msg_from_server(self->socket_pair[GSR_SOCKET_PAIR_LOCAL], response); + const int recv_res = recv_msg_from_server(self->kms_server_pid, self->socket_pair[GSR_SOCKET_PAIR_LOCAL], response); if(recv_res == 0) { fprintf(stderr, "gsr warning: gsr_kms_client_get_kms: kms server shut down\n"); strcpy(response->err_msg, "failed to receive"); |