return -1;
}
- if((fd = TEMP_FAILURE_RETRY(open( "/dev/null", O_RDWR, 0))) == -1) {
+ if ((fd = TEMP_FAILURE_RETRY(open( "/dev/null", O_RDWR, 0))) == -1) {
closeSafely(fd);
return -1;
}
void *serverThread (void * arg)
{
int socket = -1; /*Open socket by the Java client*/
- struct timeval ptime; /*Variable used by the select function, timeout control*/
- int nLeft; /*Control parameter used while receiving data from the client*/
+ long timeout, utimeout; /*Timeout for reading data from client: secs and usecs respectively*/
+ int len; /*Control parameter used while receiving data from the client*/
char buffer[1025]; /*This buffer is intended to store the data received from the client*/
char *command = NULL; /*The command sent by the client, to be executed by this process*/
uint32_t *commandLength = NULL; /*Store the command length*/
/* */
/************************************************************************************************************/
+ /*Wait max 2 seconds for data coming from client, otherwise exits with error.*/
+ timeout = 2;
+ utimeout = 0;
+
+
/*COMMAND LENGTH*/
/*First of all we receive the command size as a Java integer (4 bytes primitive type)*/
}
bzero(buffer, sizeof(buffer));
- nLeft = sizeof(uint32_t);
- /*Wait max 2 seconds for data coming from client, otherwise exits with error.*/
- ptime.tv_sec=2;
- ptime.tv_usec=0;
- if (receive_from_socket (socket, buffer, &nLeft, &ptime) < 0)
- goto err;
+ len = sizeof(uint32_t);
- if (nLeft < 0)
- syslog (LOG_INFO, "command length excessive data received, expected: 4, received: %d", (-nLeft + sizeof(uint32_t)) );
+ if (receive_from_socket (socket, buffer, len, timeout, utimeout) < 0)
+ goto err;
/*Retrieve integer (4 bytes) from buffer*/
memcpy (commandLength, buffer, sizeof(uint32_t));
*commandLength = be32toh (*commandLength);
+
/*COMMAND*/
/*Reserving commandLength + 1 because of the string end character*/
}
bzero(command, ((*commandLength) + 1));
- nLeft = *commandLength;
+ len = *commandLength;
/*Wait max 2 seconds for data coming from client, otherwise exits with error.*/
- ptime.tv_sec=2;
- ptime.tv_usec=0;
- if (receive_from_socket (socket, command, &nLeft, &ptime) < 0)
+ if (receive_from_socket (socket, command, len, timeout, utimeout) < 0)
goto err;
- if (nLeft < 0)
- syslog (LOG_INFO, "execessive command length, expected: %d, received: %d", *commandLength, (-nLeft + *commandLength));
+
/*RESULTS*/
pre_fork_system(socket, command);
+
+
/*CLOSE CONNECTION AND FINISH*/
err:
pthread_exit(0);
}
+
+
int required_sock_options (int socket)
{
int optval, flags;
return -1;
}
- if(TEMP_FAILURE_RETRY(fcntl(socket, F_SETFL, O_NONBLOCK|flags)) < 0){
+ if (TEMP_FAILURE_RETRY(fcntl(socket, F_SETFL, O_NONBLOCK|flags)) < 0){
syslog (LOG_ERR, "set socket status flags failed: %m");
return -1;
}
/*Portable programs should not rely on inheritance or noninheritance of file status flags and */
/*always explicitly set all required flags*/
optval = 1;
- if(setsockopt(socket, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval)) < 0) {
+ if (setsockopt(socket, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval)) < 0) {
syslog (LOG_ERR, "setsockopt SO_REUSEADDR failed: %m");
return -1;
}
/*Enable keepalive for this socket*/
optval = 1;
- if(setsockopt(socket, SOL_SOCKET, SO_KEEPALIVE, &optval, sizeof(optval)) < 0) {
+ if (setsockopt(socket, SOL_SOCKET, SO_KEEPALIVE, &optval, sizeof(optval)) < 0) {
syslog (LOG_ERR, "setsockopt SO_KEEPALIVE failed: %m");
return -1;
}
/* apparently it just works while the handshake phase. See: */
/* http://stackoverflow.com/questions/4345415/socket-detect-connection-is-lost */
/* I have to implement an echo/ping messages protocol (application layer) */
- /* In the meanwhile this application should just be used in the localhost interface :( */
return 0;
}
-int timeout (int fd, long timeout)
+
+int readable_timeout (int fd, long timeout, long utimeout)
{
- struct timeval ptime;
- fd_set fd_read;
+ struct timeval ptime; /*Timeout, secs and usecs*/
+ fd_set fd_read; /*Values for select function.*/
ptime.tv_sec = timeout;
- ptime.tv_usec = 0;
- for (;;) {
-
- }
+ ptime.tv_usec = utimeout;
+ FD_ZERO(&fd_read);
+ FD_SET(fd, &fd_read);
+
+ return TEMP_FAILURE_RETRY(select(fd+1, &fd_read, NULL, NULL, &ptime));
}
-int receive_from_socket (int socket, char *store, int *nLeft, struct timeval *ptime)
+
+
+int receive_from_socket (int socket, char *data, int len, long timeout, long utimeout)
{
int nData, iPos; /*Control variables.*/
int ret; /*Store return value from select.*/
- fd_set fd_read; /*Values for select function.*/
nData = iPos = 0;
-
do {
- FD_ZERO(&fd_read);
- FD_SET(socket, &fd_read);
- ret = select(socket+1, &fd_read, NULL, NULL, ptime);
- if(ret == 0) {
- syslog(LOG_INFO, "receiving timeout error");
- return -1;
- }
- if(ret == -1) {
- syslog(LOG_ERR, "receiving select error: %m");
- return -1;
- }
- if((nData = recv(socket, &store[iPos], *nLeft, 0)) <= 0) {
- syslog (LOG_ERR, "read TCP socket failed: %m");
- return -1;
- }
- *nLeft -= nData;
+ ret = readable_timeout(socket, timeout, utimeout);
+
+ if (ret == 0) {
+ syslog(LOG_INFO, "receiving timeout error");
+ return -1;
+ } else if (ret == -1) {
+ syslog(LOG_ERR, "receiving error: %m");
+ return -1;
+ }
+
+ nData = TEMP_FAILURE_RETRY(recv(socket, &data[iPos], len, 0));
+
+ if (nData < 0) {
+ if ((errno != EAGAIN) && (errno != EWOULDBLOCK)) {
+ syslog (LOG_ERR, "read TCP socket failed: %m");
+ return -1;
+ } else {
+ /*see spurious readiness man select(2) BUGS section*/
+ nData = 0;
+ syslog (LOG_INFO, "read TCP socket spurious readiness");
+ }
+ } else if (nData == 0) {
+ /*if nData is 0, client closed connection but we wanted to receive more data, this is an error */
+ syslog (LOG_ERR, "expected more data from client");
+ return -1;
+ }
+
+ len -= nData;
iPos += nData;
- } while (*nLeft > 0);
+ } while (len > 0);
return 0;
}
projects / JavaForFun / commitdiff