| /****************************************************************************** |
| * File: pit_server.c |
| * |
| * Description: Contains source code for an IPv6-capable 'PIT' server. |
| * This is a derivative of the tod6 (time-of-day) server that was written |
| * by John Wenker. |
| * ....... |
| * Author of tod6: John Wenker, Sr. Software Engineer, |
| * Performance Technologies, San Diego, USA |
| * ....... |
| * The program tod6 was a time of day server. It has beeen modified |
| * to provide a microsecond timestamp on request. Modified and adapted |
| * for PIT purposes by Don Capps. [ capps@iozone.org ] |
| * |
| * This server sends the current value of gettimeofday() in |
| * microseconds back to the client, as a numerical string. |
| * |
| * /etc/services should contain "PIT" with a specified port value. |
| * |
| ******************************************************************************/ |
| /* |
| ** System header files. |
| */ |
| #include <errno.h> /* errno declaration & error codes. */ |
| #include <netdb.h> /* getaddrinfo(3) et al. */ |
| #include <netinet/in.h> /* sockaddr_in & sockaddr_in6 definition. */ |
| #include <stdio.h> /* printf(3) et al. */ |
| #include <stdlib.h> /* exit(2). */ |
| #include <string.h> /* String manipulation & memory functions. */ |
| #if defined(_SUA_) |
| #include <poll.h> /* poll(2) and related definitions. */ |
| #else |
| #include <sys/poll.h> /* poll(2) and related definitions. */ |
| #endif |
| #include <sys/socket.h> /* Socket functions (socket(2), bind(2), etc). */ |
| #include <time.h> /* time(2) & ctime(3). */ |
| #include <sys/time.h> /* gettimeofday */ |
| #include <unistd.h> /* getopt(3), read(2), etc. */ |
| /* Include for Cygnus development environment for Windows */ |
| #if defined (Windows) |
| #include <Windows.h> |
| int errno; |
| #endif |
| |
| #if defined(_SUA_) |
| extern char *optarg, *opterr; |
| #endif |
| |
| /* |
| ** Constants. |
| ** |
| ** Please remember to add PIT service to the /etc/services file. |
| */ |
| #define DFLT_SERVICE "PIT" /* Programmable Interdimensional Timer */ |
| |
| #define INVALID_DESC -1 /* Invalid file descriptor. */ |
| #define MAXCONNQLEN 3 /* Max nbr of connection requests to queue. */ |
| #define MAXTCPSCKTS 2 /* One TCP socket for IPv4 & one for IPv6. */ |
| #define MAXUDPSCKTS 2 /* One UDP socket for IPv4 & one for IPv6. */ |
| #define VALIDOPTS "vh:p:" /* Valid command options. */ |
| /* |
| ** Simple boolean type definition. |
| */ |
| int false = 0; |
| int true = 1; |
| /* |
| ** Prototypes for internal helper functions. |
| */ |
| static int openSckt( const char *service, |
| const char *protocol, |
| int desc[ ], |
| size_t *descSize ); |
| static void pit( int tSckt[ ], |
| size_t tScktSize, |
| int uSckt[ ], |
| size_t uScktSize ); |
| /* |
| ** Global data objects. |
| */ |
| static char hostBfr[ NI_MAXHOST ]; /* For use w/getnameinfo(3). */ |
| static const char *pgmName; /* Program name w/o dir prefix. */ |
| static char servBfr[ NI_MAXSERV ]; /* For use w/getnameinfo(3). */ |
| static int verbose = 0; /* Verbose mode indication. */ |
| struct timeval tm; /* Timeval structure, used with gettimeofday() */ |
| char timeStr[40]; /* String for time in microseconds */ |
| char service_name[20]; |
| int need; |
| /* |
| ** Usage macro for command syntax violations. |
| */ |
| #define USAGE \ |
| { \ |
| fprintf( stderr, \ |
| "Usage: %s [-v] -p service \n", \ |
| pgmName ); \ |
| exit( 127 ); \ |
| } /* End USAGE macro. */ |
| /* |
| ** Macro to terminate the program if a system call error occurs. The system |
| ** call must be one of the usual type that returns -1 on error. |
| */ |
| #define CHK(expr) \ |
| do \ |
| { \ |
| if ( (expr) == -1 ) \ |
| { \ |
| fprintf( stderr, \ |
| "%s (line %d): System call ERROR - %s.\n", \ |
| pgmName, \ |
| __LINE__, \ |
| strerror( errno ) ); \ |
| exit( 1 ); \ |
| } /* End IF system call failed. */ \ |
| } while ( false ) |
| /****************************************************************************** |
| * Function: main |
| * |
| * Description: |
| * Set up a PIT server and handle network requests. This server |
| * handles both TCP and UDP requests. |
| * |
| * Parameters: |
| * The usual argc and argv parameters to a main() function. |
| * |
| * Return Value: |
| * This is a daemon program and never returns. However, in the degenerate |
| * case where no sockets are created, the function returns zero. |
| ******************************************************************************/ |
| int main( int argc, |
| char *argv[ ] ) |
| { |
| int opt; |
| int tSckt[ MAXTCPSCKTS ]; /* Array of TCP socket descriptors. */ |
| size_t tScktSize = MAXTCPSCKTS; /* Size of uSckt (# of elements). */ |
| int uSckt[ MAXUDPSCKTS ]; /* Array of UDP socket descriptors. */ |
| size_t uScktSize = MAXUDPSCKTS; /* Size of uSckt (# of elements). */ |
| |
| strcpy(service_name,DFLT_SERVICE); |
| /* |
| ** Set the program name (w/o directory prefix). |
| */ |
| pgmName = strrchr( argv[ 0 ], '/' ); |
| pgmName = pgmName == NULL ? argv[ 0 ] : pgmName + 1; |
| /* |
| ** Process command options. |
| */ |
| opterr = 0; /* Turns off "invalid option" error messages. */ |
| while ( ( opt = getopt( argc, argv, VALIDOPTS ) ) >= 0 ) |
| { |
| switch ( opt ) |
| { |
| case 'v': /* Verbose mode. */ |
| { |
| verbose = true; |
| break; |
| } |
| case 'p': /* Get the port number */ |
| { |
| strcpy(service_name,optarg); |
| need++; |
| break; |
| } |
| default: |
| { |
| USAGE; |
| } |
| } /* End SWITCH on command option. */ |
| } /* End WHILE processing options. */ |
| |
| if(need < 1) |
| { |
| USAGE; |
| exit; |
| } |
| /* |
| ** Open both a TCP and UDP socket, for both IPv4 & IPv6, on which to receive |
| ** service requests. |
| */ |
| if ( ( openSckt( service_name, "tcp", tSckt, &tScktSize ) < 0 ) || |
| ( openSckt( service_name, "udp", uSckt, &uScktSize ) < 0 ) ) |
| { |
| exit( 1 ); |
| } |
| /* |
| ** Run the Programmable Interdimensional Timer server. |
| */ |
| if ( ( tScktSize > 0 ) || ( uScktSize > 0 ) ) |
| { |
| pit( tSckt, /* pit() never returns. */ |
| tScktSize, |
| uSckt, |
| uScktSize ); |
| } |
| /* |
| ** Since pit() never returns, execution only gets here if no sockets were |
| ** created. |
| */ |
| if ( verbose ) |
| { |
| fprintf( stderr, |
| "%s: No sockets opened... terminating.\n", |
| pgmName ); |
| } |
| return 0; |
| } /* End main() */ |
| /****************************************************************************** |
| * Function: openSckt |
| * |
| * Description: |
| * Open passive (server) sockets for the indicated inet service & protocol. |
| * Notice in the last sentence that "sockets" is plural. During the interim |
| * transition period while everyone is switching over to IPv6, the server |
| * application has to open two sockets on which to listen for connections... |
| * one for IPv4 traffic and one for IPv6 traffic. |
| * |
| * Parameters: |
| * service - Pointer to a character string representing the well-known port |
| * on which to listen (can be a service name or a decimal number). |
| * protocol - Pointer to a character string representing the transport layer |
| * protocol (only "tcp" or "udp" are valid). |
| * desc - Pointer to an array into which the socket descriptors are |
| * placed when opened. |
| * descSize - This is a value-result parameter. On input, it contains the |
| * max number of descriptors that can be put into 'desc' (i.e. the |
| * number of elements in the array). Upon return, it will contain |
| * the number of descriptors actually opened. Any unused slots in |
| * 'desc' are set to INVALID_DESC. |
| * |
| * Return Value: |
| * 0 on success, -1 on error. |
| ******************************************************************************/ |
| static int openSckt( const char *service, |
| const char *protocol, |
| int desc[ ], |
| size_t *descSize ) |
| { |
| struct addrinfo *ai; |
| int aiErr; |
| struct addrinfo *aiHead; |
| struct addrinfo hints = { .ai_flags = AI_PASSIVE, /* Server mode. */ |
| .ai_family = PF_UNSPEC }; /* IPv4 or IPv6. */ |
| size_t maxDescs = *descSize; |
| /* |
| ** Initialize output parameters. When the loop completes, *descSize is 0. |
| */ |
| while ( *descSize > 0 ) |
| { |
| desc[ --( *descSize ) ] = INVALID_DESC; |
| } |
| /* |
| ** Check which protocol is selected (only TCP and UDP are valid). |
| */ |
| if ( strcmp( protocol, "tcp" ) == 0 ) /* TCP protocol. */ |
| { |
| hints.ai_socktype = SOCK_STREAM; |
| hints.ai_protocol = IPPROTO_TCP; |
| } |
| else if ( strcmp( protocol, "udp" ) == 0 ) /* UDP protocol. */ |
| { |
| hints.ai_socktype = SOCK_DGRAM; |
| hints.ai_protocol = IPPROTO_UDP; |
| } |
| else /* Invalid protocol. */ |
| { |
| fprintf( stderr, |
| "%s (line %d): ERROR - Unknown transport " |
| "layer protocol \"%s\".\n", |
| pgmName, |
| __LINE__, |
| protocol ); |
| return -1; |
| } |
| /* |
| ** Look up the service's "well-known" port number. Notice that NULL is being |
| ** passed for the 'node' parameter, and that the AI_PASSIVE flag is set in |
| ** 'hints'. Thus, the program is requesting passive address information. |
| ** The network address is initialized to :: (all zeros) for IPv6 records, or |
| ** 0.0.0.0 for IPv4 records. |
| */ |
| if ( ( aiErr = getaddrinfo( NULL, |
| service, |
| &hints, |
| &aiHead ) ) != 0 ) |
| { |
| fprintf( stderr, |
| "%s (line %d): ERROR - %s.\n", |
| pgmName, |
| __LINE__, |
| gai_strerror( aiErr ) ); |
| return -1; |
| } |
| /* |
| ** For each of the address records returned, attempt to set up a passive |
| ** socket. |
| */ |
| for ( ai = aiHead; |
| ( ai != NULL ) && ( *descSize < maxDescs ); |
| ai = ai->ai_next ) |
| { |
| if ( verbose ) |
| { |
| /* |
| ** Display the current address info. Start with the protocol- |
| ** independent fields first. |
| */ |
| fprintf( stderr, |
| "Setting up a passive socket based on the " |
| "following address info:\n" |
| " ai_flags = 0x%02X\n" |
| " ai_family = %d (PF_INET = %d, PF_INET6 = %d)\n" |
| " ai_socktype = %d (SOCK_STREAM = %d, SOCK_DGRAM = %d)\n" |
| " ai_protocol = %d (IPPROTO_TCP = %d, IPPROTO_UDP = %d)\n" |
| " ai_addrlen = %d (sockaddr_in = %lu, " |
| "sockaddr_in6 = %lu)\n", |
| ai->ai_flags, |
| ai->ai_family, |
| PF_INET, |
| PF_INET6, |
| ai->ai_socktype, |
| SOCK_STREAM, |
| SOCK_DGRAM, |
| ai->ai_protocol, |
| IPPROTO_TCP, |
| IPPROTO_UDP, |
| ai->ai_addrlen, |
| sizeof( struct sockaddr_in ), |
| sizeof( struct sockaddr_in6 ) ); |
| /* |
| ** Now display the protocol-specific formatted socket address. Note |
| ** that the program is requesting that getnameinfo(3) convert the |
| ** host & service into numeric strings. |
| */ |
| getnameinfo( ai->ai_addr, |
| ai->ai_addrlen, |
| hostBfr, |
| sizeof( hostBfr ), |
| servBfr, |
| sizeof( servBfr ), |
| NI_NUMERICHOST | NI_NUMERICSERV ); |
| switch ( ai->ai_family ) |
| { |
| case PF_INET: /* IPv4 address record. */ |
| { |
| struct sockaddr_in *p = (struct sockaddr_in*) ai->ai_addr; |
| fprintf( stderr, |
| " ai_addr = sin_family: %d (AF_INET = %d, " |
| "AF_INET6 = %d)\n" |
| " sin_addr: %s\n" |
| " sin_port: %s\n", |
| p->sin_family, |
| AF_INET, |
| AF_INET6, |
| hostBfr, |
| servBfr ); |
| break; |
| } /* End CASE of IPv4. */ |
| case PF_INET6: /* IPv6 address record. */ |
| { |
| struct sockaddr_in6 *p = (struct sockaddr_in6*) ai->ai_addr; |
| fprintf( stderr, |
| " ai_addr = sin6_family: %d (AF_INET = %d, " |
| "AF_INET6 = %d)\n" |
| " sin6_addr: %s\n" |
| " sin6_port: %s\n" |
| " sin6_flowinfo: %d\n" |
| " sin6_scope_id: %d\n", |
| p->sin6_family, |
| AF_INET, |
| AF_INET6, |
| hostBfr, |
| servBfr, |
| p->sin6_flowinfo, |
| p->sin6_scope_id ); |
| break; |
| } /* End CASE of IPv6. */ |
| default: /* Can never get here, but just for completeness. */ |
| { |
| fprintf( stderr, |
| "%s (line %d): ERROR - Unknown protocol family (%d).\n", |
| pgmName, |
| __LINE__, |
| ai->ai_family ); |
| freeaddrinfo( aiHead ); |
| return -1; |
| } /* End DEFAULT case (unknown protocol family). */ |
| } /* End SWITCH on protocol family. */ |
| } /* End IF verbose mode. */ |
| /* |
| ** Create a socket using the info in the addrinfo structure. |
| */ |
| CHK( desc[ *descSize ] = socket( ai->ai_family, |
| ai->ai_socktype, |
| ai->ai_protocol ) ); |
| /* |
| ** Here is the code that prevents "IPv4 mapped addresses", as discussed |
| ** in Section 22.1.3.1. If an IPv6 socket was just created, then set the |
| ** IPV6_V6ONLY socket option. |
| */ |
| if ( ai->ai_family == PF_INET6 ) |
| { |
| #if defined( IPV6_V6ONLY ) |
| /* |
| ** Disable IPv4 mapped addresses. |
| */ |
| int v6Only = 1; |
| CHK( setsockopt( desc[ *descSize ], |
| IPPROTO_IPV6, |
| IPV6_V6ONLY, |
| &v6Only, |
| sizeof( v6Only ) ) ); |
| #else |
| /* |
| ** IPV6_V6ONLY is not defined, so the socket option can't be set and |
| ** thus IPv4 mapped addresses can't be disabled. Print a warning |
| ** message and close the socket. Design note: If the |
| ** #if...#else...#endif construct were removed, then this program |
| ** would not compile (because IPV6_V6ONLY isn't defined). That's an |
| ** acceptable approach; IPv4 mapped addresses are certainly disabled |
| ** if the program can't build! However, since this program is also |
| ** designed to work for IPv4 sockets as well as IPv6, I decided to |
| ** allow the program to compile when IPV6_V6ONLY is not defined, and |
| ** turn it into a run-time warning rather than a compile-time error. |
| ** IPv4 mapped addresses are still disabled because _all_ IPv6 traffic |
| ** is disabled (all IPv6 sockets are closed here), but at least this |
| ** way the server can still service IPv4 network traffic. |
| */ |
| fprintf( stderr, |
| "%s (line %d): WARNING - Cannot set IPV6_V6ONLY socket " |
| "option. Closing IPv6 %s socket.\n", |
| pgmName, |
| __LINE__, |
| ai->ai_protocol == IPPROTO_TCP ? "TCP" : "UDP" ); |
| CHK( close( desc[ *descSize ] ) ); |
| continue; /* Go to top of FOR loop w/o updating *descSize! */ |
| #endif /* IPV6_V6ONLY */ |
| } /* End IF this is an IPv6 socket. */ |
| /* |
| ** Bind the socket. Again, the info from the addrinfo structure is used. |
| */ |
| CHK( bind( desc[ *descSize ], |
| ai->ai_addr, |
| ai->ai_addrlen ) ); |
| /* |
| ** If this is a TCP socket, put the socket into passive listening mode |
| ** (listen is only valid on connection-oriented sockets). |
| */ |
| if ( ai->ai_socktype == SOCK_STREAM ) |
| { |
| CHK( listen( desc[ *descSize ], |
| MAXCONNQLEN ) ); |
| } |
| /* |
| ** Socket set up okay. Bump index to next descriptor array element. |
| */ |
| *descSize += 1; |
| } /* End FOR each address info structure returned. */ |
| /* |
| ** Dummy check for unused address records. |
| */ |
| if ( verbose && ( ai != NULL ) ) |
| { |
| fprintf( stderr, |
| "%s (line %d): WARNING - Some address records were " |
| "not processed due to insufficient array space.\n", |
| pgmName, |
| __LINE__ ); |
| } /* End IF verbose and some address records remain unprocessed. */ |
| /* |
| ** Clean up. |
| */ |
| freeaddrinfo( aiHead ); |
| return 0; |
| } /* End openSckt() */ |
| /****************************************************************************** |
| * Function: pit |
| * |
| * Description: |
| * Listen on a set of sockets and send the current microsecond counter |
| * that was produced by gettimeofday(), to any clients. This function |
| * never returns. |
| * |
| * Parameters: |
| * tSckt - Array of TCP socket descriptors on which to listen. |
| * tScktSize - Size of the tSckt array (nbr of elements). |
| * uSckt - Array of UDP socket descriptors on which to listen. |
| * uScktSize - Size of the uSckt array (nbr of elements). |
| * |
| * Return Value: None. |
| ******************************************************************************/ |
| static void pit( int tSckt[ ], |
| size_t tScktSize, |
| int uSckt[ ], |
| size_t uScktSize ) |
| { |
| char bfr[ 256 ]; |
| ssize_t count; |
| struct pollfd *desc; |
| size_t descSize = tScktSize + uScktSize; |
| int idx; |
| int newSckt; |
| struct sockaddr *sadr; |
| socklen_t sadrLen; |
| struct sockaddr_storage sockStor; |
| int status; |
| size_t timeLen; |
| time_t timeVal; |
| ssize_t wBytes; |
| unsigned long long secs; |
| int ret; |
| /* |
| ** Allocate memory for the poll(2) array. |
| */ |
| desc = malloc( descSize * sizeof( struct pollfd ) ); |
| if ( desc == NULL ) |
| { |
| fprintf( stderr, |
| "%s (line %d): ERROR - %s.\n", |
| pgmName, |
| __LINE__, |
| strerror( ENOMEM ) ); |
| exit( 1 ); |
| } |
| /* |
| ** Initialize the poll(2) array. |
| */ |
| for ( idx = 0; idx < descSize; idx++ ) |
| { |
| desc[ idx ].fd = idx < tScktSize ? tSckt[ idx ] |
| : uSckt[ idx - tScktSize ]; |
| desc[ idx ].events = POLLIN; |
| desc[ idx ].revents = 0; |
| } |
| /* |
| ** Main PIT server loop. Handles both TCP & UDP requests. This is |
| ** an interative server, and all requests are handled directly within the |
| ** main loop. |
| */ |
| while ( true ) /* Do forever. */ |
| { |
| /* |
| ** Wait for activity on one of the sockets. The DO..WHILE construct is |
| ** used to restart the system call in the event the process is |
| ** interrupted by a signal. |
| */ |
| do |
| { |
| status = poll( desc, |
| descSize, |
| -1 /* Wait indefinitely for input. */ ); |
| } while ( ( status < 0 ) && ( errno == EINTR ) ); |
| CHK( status ); /* Check for a bona fide system call error. */ |
| /* |
| ** Get the current time. |
| */ |
| #if defined(Windows) |
| LARGE_INTEGER freq,counter; |
| double wintime,bigcounter; |
| /* For Windows the time_of_day() is useless. It increments in 55 milli |
| * second increments. By using the Win32api one can get access to the |
| * high performance measurement interfaces. With this one can get back |
| * into the 8 to 9 microsecond resolution. |
| */ |
| QueryPerformanceFrequency(&freq); |
| QueryPerformanceCounter(&counter); |
| bigcounter=(double)counter.HighPart *(double)0xffffffff + |
| (double)counter.LowPart; |
| wintime = (double)(bigcounter/(double)freq.LowPart); |
| secs = (long long)(wintime * 1000000); |
| #else |
| ret = gettimeofday( &tm,0 ); |
| secs = ((unsigned long long)tm.tv_sec * 1000000) |
| + (unsigned long long)tm.tv_usec; |
| #endif |
| |
| ret = sprintf(timeStr,"%llu",secs); |
| timeLen = strlen( timeStr ); |
| /* |
| ** Process sockets with input available. |
| */ |
| for ( idx = 0; idx < descSize; idx++ ) |
| { |
| switch ( desc[ idx ].revents ) |
| { |
| case 0: /* No activity on this socket; try the next. */ |
| continue; |
| case POLLIN: /* Network activity. Go process it. */ |
| break; |
| default: /* Invalid poll events. */ |
| { |
| fprintf( stderr, |
| "%s (line %d): ERROR - Invalid poll event (0x%02X).\n", |
| pgmName, |
| __LINE__, |
| desc[ idx ].revents ); |
| exit( 1 ); |
| } |
| } /* End SWITCH on returned poll events. */ |
| /* |
| ** Determine if this is a TCP request or UDP request. |
| */ |
| if ( idx < tScktSize ) |
| { |
| /* |
| ** TCP connection requested. Accept it. Notice the use of |
| ** the sockaddr_storage data type. |
| */ |
| sadrLen = sizeof( sockStor ); |
| sadr = (struct sockaddr*) &sockStor; |
| CHK( newSckt = accept( desc[ idx ].fd, |
| sadr, |
| &sadrLen ) ); |
| CHK( shutdown( newSckt, /* Server never recv's anything. */ |
| SHUT_RD ) ); |
| if ( verbose ) |
| { |
| /* |
| ** Display the socket address of the remote client. Begin with |
| ** the address-independent fields. |
| */ |
| fprintf( stderr, |
| "Sockaddr info for new TCP client:\n" |
| " sa_family = %d (AF_INET = %d, AF_INET6 = %d)\n" |
| " addr len = %d (sockaddr_in = %lu, " |
| "sockaddr_in6 = %lu)\n", |
| sadr->sa_family, |
| AF_INET, |
| AF_INET6, |
| sadrLen, |
| sizeof( struct sockaddr_in ), |
| sizeof( struct sockaddr_in6 ) ); |
| /* |
| ** Display the address-specific fields. |
| */ |
| getnameinfo( sadr, |
| sadrLen, |
| hostBfr, |
| sizeof( hostBfr ), |
| servBfr, |
| sizeof( servBfr ), |
| NI_NUMERICHOST | NI_NUMERICSERV ); |
| /* |
| ** Notice that we're switching on an address family now, not a |
| ** protocol family. |
| */ |
| switch ( sadr->sa_family ) |
| { |
| case AF_INET: /* IPv4 address. */ |
| { |
| struct sockaddr_in *p = (struct sockaddr_in*) sadr; |
| fprintf( stderr, |
| " sin_addr = sin_family: %d\n" |
| " sin_addr: %s\n" |
| " sin_port: %s\n", |
| p->sin_family, |
| hostBfr, |
| servBfr ); |
| break; |
| } /* End CASE of IPv4. */ |
| case AF_INET6: /* IPv6 address. */ |
| { |
| struct sockaddr_in6 *p = (struct sockaddr_in6*) sadr; |
| fprintf( stderr, |
| " sin6_addr = sin6_family: %d\n" |
| " sin6_addr: %s\n" |
| " sin6_port: %s\n" |
| " sin6_flowinfo: %d\n" |
| " sin6_scope_id: %d\n", |
| p->sin6_family, |
| hostBfr, |
| servBfr, |
| p->sin6_flowinfo, |
| p->sin6_scope_id ); |
| break; |
| } /* End CASE of IPv6. */ |
| default: /* Can never get here, but for completeness. */ |
| { |
| fprintf( stderr, |
| "%s (line %d): ERROR - Unknown address " |
| "family (%d).\n", |
| pgmName, |
| __LINE__, |
| sadr->sa_family ); |
| break; |
| } /* End DEFAULT case (unknown address family). */ |
| } /* End SWITCH on address family. */ |
| } /* End IF verbose mode. */ |
| /* |
| ** Send the PIT to the client. |
| */ |
| wBytes = timeLen; |
| while ( wBytes > 0 ) |
| { |
| do |
| { |
| count = write( newSckt, |
| timeStr, |
| wBytes ); |
| } while ( ( count < 0 ) && ( errno == EINTR ) ); |
| CHK( count ); /* Check for an error. */ |
| wBytes -= count; |
| } /* End WHILE there is data to send. */ |
| CHK( close( newSckt ) ); |
| } /* End IF this was a TCP connection request. */ |
| else |
| { |
| /* |
| ** This is a UDP socket, and a datagram is available. The funny |
| ** thing about UDP requests is that this server doesn't require any |
| ** client input; but it can't send the PIT unless it knows a client |
| ** wants the data, and the only way that can occur with UDP is if |
| ** the server receives a datagram from the client. Thus, the |
| ** server must receive _something_, but the content of the datagram |
| ** is irrelevant. Read in the datagram. Again note the use of |
| ** sockaddr_storage to receive the address. |
| */ |
| sadrLen = sizeof( sockStor ); |
| sadr = (struct sockaddr*) &sockStor; |
| CHK( count = recvfrom( desc[ idx ].fd, |
| bfr, |
| sizeof( bfr ), |
| 0, |
| sadr, |
| &sadrLen ) ); |
| /* |
| ** Display whatever was received on stdout. |
| */ |
| if ( verbose ) |
| { |
| ssize_t rBytes = count; |
| fprintf( stderr, |
| "%s: UDP datagram received (%ld bytes).\n", |
| pgmName, |
| count ); |
| while ( count > 0 ) |
| { |
| fputc( bfr[ rBytes - count-- ], |
| stdout ); |
| } |
| if ( bfr[ rBytes-1 ] != '\n' ) |
| fputc( '\n', stdout ); /* Newline also flushes stdout. */ |
| /* |
| ** Display the socket address of the remote client. Address- |
| ** independent fields first. |
| */ |
| fprintf( stderr, |
| "Remote client's sockaddr info:\n" |
| " sa_family = %d (AF_INET = %d, AF_INET6 = %d)\n" |
| " addr len = %d (sockaddr_in = %lu, " |
| "sockaddr_in6 = %lu)\n", |
| sadr->sa_family, |
| AF_INET, |
| AF_INET6, |
| sadrLen, |
| sizeof( struct sockaddr_in ), |
| sizeof( struct sockaddr_in6 ) ); |
| /* |
| ** Display the address-specific information. |
| */ |
| getnameinfo( sadr, |
| sadrLen, |
| hostBfr, |
| sizeof( hostBfr ), |
| servBfr, |
| sizeof( servBfr ), |
| NI_NUMERICHOST | NI_NUMERICSERV ); |
| switch ( sadr->sa_family ) |
| { |
| case AF_INET: /* IPv4 address. */ |
| { |
| struct sockaddr_in *p = (struct sockaddr_in*) sadr; |
| fprintf( stderr, |
| " sin_addr = sin_family: %d\n" |
| " sin_addr: %s\n" |
| " sin_port: %s\n", |
| p->sin_family, |
| hostBfr, |
| servBfr ); |
| break; |
| } /* End CASE of IPv4 address. */ |
| case AF_INET6: /* IPv6 address. */ |
| { |
| struct sockaddr_in6 *p = (struct sockaddr_in6*) sadr; |
| fprintf( stderr, |
| " sin6_addr = sin6_family: %d\n" |
| " sin6_addr: %s\n" |
| " sin6_port: %s\n" |
| " sin6_flowinfo: %d\n" |
| " sin6_scope_id: %d\n", |
| p->sin6_family, |
| hostBfr, |
| servBfr, |
| p->sin6_flowinfo, |
| p->sin6_scope_id ); |
| break; |
| } /* End CASE of IPv6 address. */ |
| default: /* Can never get here, but for completeness. */ |
| { |
| fprintf( stderr, |
| "%s (line %d): ERROR - Unknown address " |
| "family (%d).\n", |
| pgmName, |
| __LINE__, |
| sadr->sa_family ); |
| break; |
| } /* End DEFAULT case (unknown address family). */ |
| } /* End SWITCH on address family. */ |
| } /* End IF verbose mode. */ |
| /* |
| ** Send the PIT to the client. |
| */ |
| wBytes = timeLen; |
| while ( wBytes > 0 ) |
| { |
| do |
| { |
| count = sendto( desc[ idx ].fd, |
| timeStr, |
| wBytes, |
| 0, |
| sadr, /* Address & address length */ |
| sadrLen ); /* received in recvfrom(). */ |
| } while ( ( count < 0 ) && ( errno == EINTR ) ); |
| CHK( count ); /* Check for a bona fide error. */ |
| wBytes -= count; |
| } /* End WHILE there is data to send. */ |
| } /* End ELSE a UDP datagram is available. */ |
| desc[ idx ].revents = 0; /* Clear the returned poll events. */ |
| } /* End FOR each socket descriptor. */ |
| } /* End WHILE forever. */ |
| } /* End pit() */ |
| |
