[151] | 1 | #include <stdio.h> |
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| 2 | #include <stdlib.h> |
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| 3 | #include <string.h> |
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| 4 | #include <sys/socket.h> |
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| 5 | #include <arpa/inet.h> |
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| 6 | #include <netdb.h> |
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| 7 | #include <unistd.h> |
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| 8 | #include <signal.h> |
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| 9 | #include <errno.h> |
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| 10 | #include <sys/wait.h> |
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| 11 | #include <sys/stat.h> |
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| 12 | #include <stdarg.h> |
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| 13 | #include <syslog.h> |
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| 14 | |
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| 15 | //#include <iostream> |
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| 16 | #include <sys/types.h> |
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| 17 | #include <sys/stat.h> |
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| 18 | #include <fcntl.h> |
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| 19 | #include <sys/time.h> |
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| 20 | #include <semaphore.h> |
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| 21 | #include <sys/mman.h> |
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| 22 | #include <stdarg.h> |
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| 23 | |
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| 24 | // Buffer size, in bytes, used for copying in the Cat() function. |
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| 25 | const size_t BUF_SIZE = 10240; |
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| 26 | |
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| 27 | // Typedef for a signal handler function. |
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| 28 | typedef void (*signal_handler_t) (int); |
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| 29 | |
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| 30 | // Prototypes for functions in this file. |
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| 31 | void ParseArgs (int, char **, struct in_addr *, unsigned short *, struct in_addr *, unsigned short *); |
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| 32 | void Initialise (void); |
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| 33 | void sig_child (int); |
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| 34 | int CreateServerSocket (struct in_addr, unsigned short); |
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| 35 | void Daemonise (void); |
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| 36 | void MainLoop (int, struct in_addr, unsigned short); |
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| 37 | void Proxy (int, int); |
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| 38 | int AcceptClientConnection (int); |
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| 39 | int ConnectToServer (struct in_addr, unsigned short); |
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| 40 | void Cat (int, int); |
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| 41 | int NameToAddr (const char *, struct in_addr *); |
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| 42 | int NameToPort (const char *, unsigned short *, const char *); |
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| 43 | #ifdef __GNUC__ |
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| 44 | void quit (const char *, ...) __attribute__ ((format (printf, 1, 2))); |
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| 45 | void pbomb (const char *, ...) __attribute__ ((format (printf, 1, 2))); |
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| 46 | void hbomb (const char *, ...) __attribute__ ((format (printf, 1, 2))); |
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| 47 | #else |
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| 48 | void quit (const char *, ...); |
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| 49 | void pbomb (const char *, ...); |
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| 50 | void hbomb (const char *, ...); |
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| 51 | #endif |
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| 52 | void set_signal_handler (int, signal_handler_t); |
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| 53 | |
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| 54 | // Global variables |
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| 55 | char g_program_name[100]; // Initialised from argv[0] in ParseArgs() |
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| 56 | |
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| 57 | struct accept |
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| 58 | { |
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| 59 | int newfd; |
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| 60 | struct sockaddr_in sa; |
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| 61 | struct in_addr jabber_addr; |
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| 62 | unsigned short jabber_port; |
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| 63 | }; |
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| 64 | |
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| 65 | int main (int argc, char *argv[]) |
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| 66 | { |
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| 67 | struct in_addr remote_addr, |
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| 68 | local_addr; |
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| 69 | unsigned short remote_port, |
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| 70 | local_port; |
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| 71 | int listen_fd; |
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| 72 | |
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| 73 | ParseArgs(argc, argv, &remote_addr, &remote_port, &local_addr, &local_port); |
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| 74 | |
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| 75 | Initialise(); |
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| 76 | |
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| 77 | // Create server socket before becoming |
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| 78 | // a daemon so there is still a chance |
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| 79 | // to print an error message. |
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| 80 | |
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| 81 | listen_fd = CreateServerSocket(local_addr, local_port); |
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| 82 | if ( listen_fd < 0 ) |
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| 83 | pbomb("Unable to create server socket"); |
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| 84 | |
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| 85 | Daemonise(); |
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| 86 | |
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| 87 | MainLoop(listen_fd, remote_addr, remote_port); // never returns |
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| 88 | |
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| 89 | exit(EXIT_SUCCESS); |
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| 90 | } |
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| 91 | |
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| 92 | // ParseArgs() |
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| 93 | // Parse the command line arguments to extract the remote |
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| 94 | // and local adresses and port numbers, ra, rp, la & lp. |
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| 95 | // Exit the program gracefully upon error. |
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| 96 | void ParseArgs (int argc, char *argv[], struct in_addr *ra, unsigned short *rp, struct in_addr *la, unsigned short *lp) |
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| 97 | { |
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| 98 | // argv[0] = program name |
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| 99 | // argv[1] = remote_addr |
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| 100 | // argv[2] = remote_port |
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| 101 | // argv[3] = local_addr (optional) |
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| 102 | // argv[4] = local_port (optional) |
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| 103 | |
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| 104 | char * p = strrchr(argv[0], '/'); |
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| 105 | |
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| 106 | strncpy(g_program_name, (p == NULL) ? argv[0] : p + 1, sizeof(g_program_name) - 1); |
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| 107 | |
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| 108 | if ( (argc < 3) || (argc > 5) ) |
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| 109 | { |
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| 110 | fprintf (stderr, "usage: %s remote_addr remote_port [local_addr] [local_port]\n", argv[0]); |
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| 111 | exit (EXIT_FAILURE); |
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| 112 | } |
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| 113 | |
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| 114 | if ( NameToAddr(argv[1], ra) ) |
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| 115 | hbomb("Unable to resolve \"%s\" to an ip address", argv[1]); |
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| 116 | |
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| 117 | if ( NameToPort(argv[2], rp, "tcp") ) |
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| 118 | quit("Unable to resolve \"%s\" to a port number", argv[2]); |
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| 119 | |
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| 120 | if ( argc < 4 ) |
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| 121 | la->s_addr = htonl(INADDR_ANY); |
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| 122 | else |
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| 123 | if ( NameToAddr(argv[3], la) ) |
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| 124 | hbomb ("Unable to resolve \"%s\" to an ip address", argv[3]); |
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| 125 | |
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| 126 | if ( argc < 5 ) |
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| 127 | memcpy(lp, rp, sizeof(*lp)); |
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| 128 | else |
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| 129 | if ( NameToPort(argv[4], lp, "tcp") ) |
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| 130 | quit("Unable to resolve \"%s\" to a port number", argv[4]); |
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| 131 | } |
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| 132 | |
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| 133 | // Initialise() |
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| 134 | // Setup syslog, signal handlers, and other intialisation. |
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| 135 | void Initialise (void) |
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| 136 | { |
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| 137 | openlog(g_program_name, LOG_PID, LOG_USER); |
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| 138 | syslog(LOG_INFO, "%s started", g_program_name); |
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| 139 | |
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| 140 | chdir ("/"); // Change working directory to the root. |
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| 141 | |
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| 142 | umask (0); // Clear our file mode creation mask |
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| 143 | |
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| 144 | set_signal_handler(SIGCHLD, sig_child); |
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| 145 | |
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| 146 | signal(SIGPIPE, SIG_IGN); |
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| 147 | } |
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| 148 | |
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| 149 | // sig_child() |
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| 150 | // Handles SIGCHLD from exiting child processes. |
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| 151 | void sig_child (int signo) |
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| 152 | { |
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| 153 | pid_t pid = 1; |
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| 154 | |
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| 155 | (void) signo; // suppress compiler warning |
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| 156 | |
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| 157 | while ( pid > 0 ) |
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| 158 | { |
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| 159 | pid = waitpid(WAIT_ANY, NULL, WNOHANG); |
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| 160 | |
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| 161 | if ( pid > 0 ) |
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| 162 | syslog(LOG_INFO, "Caught SIGCHLD from pid %d", pid); |
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| 163 | //else |
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| 164 | // break; |
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| 165 | } |
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| 166 | |
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| 167 | if ( (pid < 0) && (errno != ECHILD) ) |
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| 168 | syslog(LOG_ERR, "waitpid(): %m"), exit(EXIT_FAILURE); |
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| 169 | |
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| 170 | return; |
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| 171 | } |
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| 172 | |
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| 173 | // CreateServerSocket() |
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| 174 | // Create a socket, bind it to the specified address |
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| 175 | // and port, and set it to listen for client connections. |
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| 176 | // Returns < 0 on failure to bind, bombs on error otherwise, |
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| 177 | // returns the fd of the new socket on success. |
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| 178 | int CreateServerSocket (struct in_addr addr, unsigned short port) |
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| 179 | { |
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| 180 | int err, |
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| 181 | fd; |
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| 182 | const int on = 1; |
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| 183 | struct sockaddr_in sa; |
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| 184 | |
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| 185 | // Create a socket and get its descriptor. |
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| 186 | fd = socket(AF_INET, SOCK_STREAM, 0); |
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| 187 | if ( fd < 0 ) |
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| 188 | syslog(LOG_ERR, "socket(): %m"), exit(EXIT_FAILURE); |
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| 189 | |
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| 190 | // Set SO_REUSEADDR socket option |
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| 191 | if ( setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0 ) |
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| 192 | syslog(LOG_ERR, "setsockopt(fd%d, SO_REUSEADDR): %m", fd); |
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| 193 | |
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| 194 | // Load a sa structure with the specified address and port |
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| 195 | sa.sin_family = AF_INET; |
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| 196 | sa.sin_port = htons(port); |
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| 197 | sa.sin_addr = addr; |
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| 198 | memset(sa.sin_zero, 0, sizeof(sa.sin_zero)); |
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| 199 | |
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| 200 | // Bind our socket to the address and port specified |
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| 201 | err = bind(fd, (struct sockaddr *) &sa, sizeof(sa)); |
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| 202 | if ( err < 0 ) |
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| 203 | { |
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| 204 | syslog(LOG_ERR, "bind(): %m"); |
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| 205 | return err; |
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| 206 | } |
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| 207 | |
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| 208 | // Tell socket to listen and queue up to 5 incoming connections. |
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| 209 | if ( listen (fd, 5) < 0 ) |
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| 210 | syslog(LOG_ERR, "listen(): %m"), exit(EXIT_FAILURE); |
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| 211 | |
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| 212 | return fd; |
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| 213 | } |
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| 214 | |
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| 215 | // Daemonise() |
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| 216 | // Put the program in the background, set |
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| 217 | // PPID=1, create a new session and process |
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| 218 | // group, without a controlling tty. |
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| 219 | void Daemonise (void) |
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| 220 | { |
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| 221 | pid_t pid; |
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| 222 | |
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| 223 | // Close stdin, stdout & stderr |
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| 224 | // TODO: |
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| 225 | // open /dev/null and dup the fd to stdin, stdout & stderr |
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| 226 | // close(STDIN_FILENO); |
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| 227 | // close(STDOUT_FILENO); |
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| 228 | // close(STDERR_FILENO); |
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| 229 | |
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| 230 | syslog (LOG_INFO, "%s daemonising", g_program_name); |
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| 231 | |
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| 232 | // Fork the process to put it in the background. |
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| 233 | |
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| 234 | pid = fork(); |
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| 235 | if ( pid == -1 ) |
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| 236 | syslog (LOG_ERR, "fork(): %m"), exit(EXIT_FAILURE); |
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| 237 | |
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| 238 | // parent terminates here, so shell thinks the command is done. |
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| 239 | if ( pid ) |
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| 240 | exit(0); |
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| 241 | |
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| 242 | syslog(LOG_INFO, "%s in background", g_program_name); |
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| 243 | |
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| 244 | // 1st child continues to run in the background with PPID=1 |
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| 245 | |
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| 246 | // Become leader of a new session and a new process group, |
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| 247 | // with no controlling tty. |
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| 248 | setsid(); |
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| 249 | |
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| 250 | // Fork again to guarantee the process will not be able |
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| 251 | // to aquire a controlling tty. |
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| 252 | |
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| 253 | // signal (SIGHUP, SIG_IGN); // required according to Stevens' UNP2 p333 |
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| 254 | |
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| 255 | pid = fork(); |
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| 256 | if ( pid == -1 ) |
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| 257 | syslog(LOG_ERR, "fork(): %m"), exit(EXIT_FAILURE); |
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| 258 | |
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| 259 | if ( pid ) // 1st child terminates |
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| 260 | exit(0); |
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| 261 | |
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| 262 | // 2nd child continues, no longer a session or group leader |
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| 263 | |
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| 264 | syslog(LOG_INFO, "%s daemonised", g_program_name); |
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| 265 | } |
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| 266 | |
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| 267 | struct cli |
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| 268 | { |
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| 269 | char user[100]; |
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| 270 | }; |
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| 271 | |
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| 272 | struct client |
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| 273 | { |
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| 274 | char user[100]; |
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| 275 | struct client * next; |
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| 276 | } client; |
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| 277 | |
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| 278 | struct shared { |
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| 279 | sem_t mutex; |
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| 280 | int count; |
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| 281 | //struct cli clients[100]; |
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| 282 | struct client * clients; |
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| 283 | } shared; |
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| 284 | |
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| 285 | void teste(struct client * current) |
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| 286 | { |
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| 287 | while ( current != (struct client *)NULL ) |
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| 288 | { |
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| 289 | printf("%s...\n", current->user); |
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| 290 | current = current->next; |
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| 291 | } |
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| 292 | //puts("\nFIM FUNCAO TEST\n\n"); |
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| 293 | } |
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| 294 | |
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| 295 | void share_memory(void (* func)(struct client *)) |
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| 296 | { |
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| 297 | static struct shared * ptr = (struct shared *)NULL; |
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| 298 | int fd = (int)NULL; |
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| 299 | struct client * new, |
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| 300 | * current; |
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| 301 | |
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| 302 | if ( ptr == (struct shared *)NULL ) |
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| 303 | { |
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| 304 | if ( (fd = open("/tmp/data.txt", O_RDWR | O_CREAT, 0660)) == -1 ) |
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| 305 | fprintf(stderr,"error opening file\n"); |
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| 306 | |
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| 307 | write(fd, &shared, sizeof(struct shared)); |
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| 308 | ptr = (struct shared *) mmap(NULL, sizeof(struct shared), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); |
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| 309 | close(fd); |
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| 310 | |
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| 311 | fd = (int)NULL; |
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| 312 | |
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| 313 | if ( sem_init(&ptr->mutex, 1, 1) != 0 ) |
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| 314 | fprintf(stderr,"sem_init error"), exit(-2); |
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| 315 | |
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| 316 | ptr->count = 0; |
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| 317 | ptr->clients = (struct client *)NULL; |
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| 318 | } |
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| 319 | |
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| 320 | // begin mutex |
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| 321 | sem_wait(&ptr->mutex); |
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| 322 | |
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| 323 | if ( ptr->clients == (struct client *)NULL ) |
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| 324 | { |
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| 325 | if ( (fd = open("/tmp/clients.txt", O_RDWR | O_CREAT, 0660)) == -1 ) |
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| 326 | fprintf(stderr,"error opening file\n"); |
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| 327 | write(fd, &client, sizeof(struct client)); |
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| 328 | ptr->clients= (struct client *) mmap(NULL, 10 * sizeof(struct client), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); |
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| 329 | close(fd); |
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| 330 | |
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| 331 | fd = (int)NULL; |
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| 332 | |
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| 333 | current = ptr->clients; |
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| 334 | current->next = (struct client *)NULL; |
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| 335 | } |
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| 336 | else |
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| 337 | { |
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| 338 | /* |
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| 339 | current = ptr->clients; |
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| 340 | if ( current->next == (struct client *)NULL ) |
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| 341 | { |
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| 342 | if ( (fd = open("clients.txt", O_RDWR | O_APPEND | O_CREAT, 0660)) == -1 ) |
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| 343 | fprintf(stderr,"error opening file\n"); |
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| 344 | |
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| 345 | puts("write"); |
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| 346 | write(fd, &client, sizeof(struct client)); |
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| 347 | puts("mmap"); |
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| 348 | current->next = (struct client *) mmap(NULL, sizeof(struct client), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); |
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| 349 | puts("close"); |
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| 350 | close(fd); |
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| 351 | |
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| 352 | puts("ATRIBUINDO NULL"); |
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| 353 | current->next->next = (struct client *)NULL; |
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| 354 | puts("CURRENT = CURRENT->NEXT"); |
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| 355 | current = current->next; |
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| 356 | puts("__"); |
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| 357 | } |
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| 358 | else |
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| 359 | { |
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| 360 | puts("\nINICIADA\n"); |
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| 361 | }*/ |
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| 362 | |
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| 363 | current = ptr->clients; |
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| 364 | while ( current->next != (struct client *)NULL ) |
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| 365 | current = current->next; |
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| 366 | |
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| 367 | /*if ( (fd = open("clients.txt", O_RDWR | O_APPEND | O_CREAT, 0660)) == -1 ) |
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| 368 | fprintf(stderr,"error opening file\n"); |
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| 369 | write(fd, &client, sizeof(struct client)); |
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| 370 | new = / *(struct client *)* / mmap(NULL, sizeof(struct client), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); |
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| 371 | //current->next = (struct client *) mmap(NULL, sizeof(struct client), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); |
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| 372 | close(fd);*/ |
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| 373 | |
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| 374 | current = current->next = new; |
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| 375 | current->next = (struct client *)NULL; |
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| 376 | } |
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| 377 | |
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| 378 | puts("\nWORKING\n\n"); |
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| 379 | |
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| 380 | setbuf(stdout, NULL); |
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| 381 | |
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| 382 | printf("current value: %d\n", ptr->count); |
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| 383 | bzero(current->user, 100); |
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| 384 | sprintf(current->user, "teste - %d", ptr->count); |
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| 385 | |
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| 386 | func(ptr->first); |
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| 387 | |
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| 388 | ptr->count++; |
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| 389 | |
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| 390 | // end mutex |
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| 391 | sem_post(&ptr->mutex); |
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| 392 | } |
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| 393 | |
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| 394 | // MainLoop() |
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| 395 | // Classic concurrent server model. |
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| 396 | // Wait for a client to connect, fork a child process |
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| 397 | // to do the business with the client, parent process |
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| 398 | // continues to wait for the next connection. |
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| 399 | // This function does not return. |
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| 400 | void MainLoop (int listen_fd, struct in_addr rem_addr, unsigned short rem_port) |
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| 401 | { |
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| 402 | int server_fd, |
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| 403 | client_fd; |
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| 404 | pid_t child_pid; |
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| 405 | |
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| 406 | for ( ; ; ) |
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| 407 | { |
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| 408 | client_fd = AcceptClientConnection (listen_fd); |
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| 409 | share_memory(teste); |
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| 410 | |
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| 411 | child_pid = fork(); |
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| 412 | if ( child_pid == -1 ) |
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| 413 | syslog(LOG_ERR, "fork(): %m"), exit(EXIT_FAILURE); |
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| 414 | |
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| 415 | if ( child_pid ) // parent |
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| 416 | { |
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| 417 | close(client_fd); |
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| 418 | |
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| 419 | syslog(LOG_INFO, "Forked child pid %d to deal with client", child_pid); |
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| 420 | } |
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| 421 | else // child |
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| 422 | { |
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| 423 | close(listen_fd); |
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| 424 | |
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| 425 | server_fd = ConnectToServer(rem_addr, rem_port); |
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| 426 | |
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| 427 | Proxy(server_fd, client_fd); |
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| 428 | |
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| 429 | syslog(LOG_INFO, "exiting"); |
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| 430 | _exit(0); |
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| 431 | } |
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| 432 | } |
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| 433 | } |
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| 434 | |
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| 435 | // Proxy() |
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| 436 | // Copies data between server_fd and client_fd |
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| 437 | // in both directions until one or other peer |
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| 438 | // closes their connection. |
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| 439 | void Proxy (int server_fd, int client_fd) |
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| 440 | { |
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| 441 | pid_t helper_pid; |
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| 442 | |
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| 443 | syslog(LOG_INFO, "Proxy(fd%d, fd%d)", server_fd, client_fd); |
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| 444 | |
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| 445 | signal(SIGCHLD, SIG_IGN); |
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| 446 | |
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| 447 | helper_pid = fork(); |
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| 448 | if ( helper_pid == -1 ) |
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| 449 | syslog(LOG_ERR, "fork(): %m"), exit(EXIT_FAILURE); |
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| 450 | |
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| 451 | if ( helper_pid ) // parent |
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| 452 | { |
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| 453 | syslog(LOG_INFO, "Forked child pid %d to help with proxying", helper_pid); |
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| 454 | |
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| 455 | Cat(server_fd, client_fd); |
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| 456 | |
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| 457 | shutdown(client_fd, 1); |
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| 458 | close(server_fd); |
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| 459 | close(client_fd); |
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| 460 | |
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| 461 | wait(0); // wait for helper to exit |
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| 462 | } |
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| 463 | else // child (helper) |
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| 464 | { |
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| 465 | Cat(client_fd, server_fd); |
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| 466 | |
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| 467 | shutdown(server_fd, 1); |
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| 468 | |
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| 469 | syslog(LOG_INFO, "exiting"); |
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| 470 | exit(0); // helper exits here |
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| 471 | } |
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| 472 | } |
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| 473 | |
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| 474 | // AcceptClientConnection() |
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| 475 | // waits for a tcp connect to the socket listen_fd, which |
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| 476 | // must already be bound and set to listen on a local port. |
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| 477 | // Bombs on error, returns the fd of the new socket on success. |
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| 478 | int AcceptClientConnection (int listen_fd) |
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| 479 | { |
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| 480 | int newfd; |
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| 481 | struct sockaddr_in sa; |
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| 482 | socklen_t socklen; |
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| 483 | |
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| 484 | syslog(LOG_INFO, "AcceptClientConnection(fd%d)", listen_fd); |
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| 485 | |
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| 486 | // Accept the connection and create a new socket for it. |
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| 487 | socklen = sizeof(sa); |
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| 488 | memset(&sa, 0, socklen); |
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| 489 | do |
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| 490 | { |
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| 491 | newfd = accept(listen_fd, (struct sockaddr *) &sa, &socklen); |
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| 492 | } |
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| 493 | while ( (newfd < 0) && (errno == EINTR) ); |
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| 494 | |
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| 495 | syslog(LOG_INFO, "Accepted client connection on new socket fd%d", newfd); |
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| 496 | |
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| 497 | if ( newfd < 0 ) |
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| 498 | syslog(LOG_ERR, "accept(): %m"), exit(EXIT_FAILURE); |
---|
| 499 | |
---|
| 500 | if ( socklen != sizeof(sa) ) |
---|
| 501 | syslog(LOG_ERR, "accept() screwed up!"), exit(EXIT_FAILURE); |
---|
| 502 | |
---|
| 503 | return newfd; |
---|
| 504 | } |
---|
| 505 | |
---|
| 506 | // ConnectToServer() |
---|
| 507 | // attempts a tcp connect to the server specified |
---|
| 508 | // by addr and port. Bombs on failure to connect, |
---|
| 509 | // returns the fd of the new socket on success. |
---|
| 510 | int ConnectToServer (struct in_addr addr, unsigned short port) |
---|
| 511 | { |
---|
| 512 | // TODO: |
---|
| 513 | // have a timeout for connect() |
---|
| 514 | // see Unix socket FAQ 6.2 |
---|
| 515 | |
---|
| 516 | int fd, |
---|
| 517 | err; |
---|
| 518 | struct sockaddr_in sa; |
---|
| 519 | |
---|
| 520 | // Create a socket and get its descriptor. |
---|
| 521 | fd = socket(AF_INET, SOCK_STREAM, 0); |
---|
| 522 | if ( fd < 0 ) |
---|
| 523 | syslog(LOG_ERR, "socket(): %m"), exit(EXIT_FAILURE); |
---|
| 524 | |
---|
| 525 | sa.sin_family = AF_INET; |
---|
| 526 | sa.sin_port = htons(port); |
---|
| 527 | sa.sin_addr = addr; |
---|
| 528 | memset(sa.sin_zero, 0, sizeof(sa.sin_zero)); |
---|
| 529 | |
---|
| 530 | err = connect(fd, (struct sockaddr *) &sa, sizeof(sa)); |
---|
| 531 | if ( err < 0 ) |
---|
| 532 | { |
---|
| 533 | syslog(LOG_ERR, "Unable to connect socket fd%d to server: %m", fd); |
---|
| 534 | exit(EXIT_FAILURE); |
---|
| 535 | } |
---|
| 536 | |
---|
| 537 | syslog(LOG_INFO, "Connected socket fd%d to server", fd); |
---|
| 538 | |
---|
| 539 | return fd; |
---|
| 540 | } |
---|
| 541 | |
---|
| 542 | // Cat() |
---|
| 543 | // read data from in_fd and write it to out_fd until |
---|
| 544 | // the connection is closed by one of the peers. |
---|
| 545 | // Data is copied using a dynamically allocated buffer. |
---|
| 546 | void Cat (int in_fd, int out_fd) |
---|
| 547 | { |
---|
| 548 | unsigned char * const buf = malloc(BUF_SIZE); |
---|
| 549 | int bytes_rcvd, |
---|
| 550 | bytes_sent = 0, |
---|
| 551 | i; |
---|
| 552 | |
---|
| 553 | syslog(LOG_INFO, "Cat(fd%d, fd%d)", in_fd, out_fd); |
---|
| 554 | |
---|
| 555 | if ( buf == NULL ) |
---|
| 556 | syslog(LOG_ERR, "malloc(): %m"), exit(EXIT_FAILURE); |
---|
| 557 | |
---|
| 558 | do |
---|
| 559 | { |
---|
| 560 | bytes_rcvd = recv(in_fd, buf, BUF_SIZE, 0); |
---|
| 561 | |
---|
| 562 | for ( i = 0; i < bytes_rcvd || bytes_sent < 0; i += bytes_sent ) |
---|
| 563 | { |
---|
| 564 | bytes_sent = send(out_fd, buf + i, bytes_rcvd - i, 0); |
---|
| 565 | |
---|
| 566 | //if ( bytes_sent < 0 ) |
---|
| 567 | // break; |
---|
| 568 | } |
---|
| 569 | |
---|
| 570 | } |
---|
| 571 | while ( (bytes_rcvd > 0) && (bytes_sent > 0) ); |
---|
| 572 | |
---|
| 573 | if ( (bytes_rcvd < 0) && (errno != ECONNRESET) ) |
---|
| 574 | syslog(LOG_ERR, "recv(): %m"), exit(EXIT_FAILURE); |
---|
| 575 | |
---|
| 576 | if ( (bytes_sent < 0) && (errno != EPIPE) ) |
---|
| 577 | syslog(LOG_ERR, "send(): %m"), exit(EXIT_FAILURE); |
---|
| 578 | |
---|
| 579 | free(buf); |
---|
| 580 | } |
---|
| 581 | |
---|
| 582 | // NameToAddress() |
---|
| 583 | // Convert name to an ip address. |
---|
| 584 | // Returns 0 on success, -1 on failure. |
---|
| 585 | int NameToAddr (const char * name, struct in_addr * p_inaddr) |
---|
| 586 | { |
---|
| 587 | struct hostent * he; |
---|
| 588 | |
---|
| 589 | // First, attempt to convert from string ip format |
---|
| 590 | // TODO: |
---|
| 591 | // use inet_aton() instead |
---|
| 592 | p_inaddr->s_addr = inet_addr(name); |
---|
| 593 | if ( p_inaddr->s_addr != -1U ) // Success |
---|
| 594 | return 0; |
---|
| 595 | |
---|
| 596 | // Next, attempt to read from /etc/hosts or do a DNS lookup |
---|
| 597 | he = gethostbyname(name); |
---|
| 598 | if ( he != NULL ) // Success |
---|
| 599 | { |
---|
| 600 | memcpy(p_inaddr, he->h_addr, sizeof(struct in_addr)); |
---|
| 601 | return 0; |
---|
| 602 | } |
---|
| 603 | |
---|
| 604 | return -1; // Failed to resolve name to an ip address |
---|
| 605 | } |
---|
| 606 | |
---|
| 607 | // NameToPort() |
---|
| 608 | // Convert name to a port number. Name can either be a port name |
---|
| 609 | // (in which case proto must also be set to either "tcp" or "udp") |
---|
| 610 | // or name can be the ascii representation of the port number. |
---|
| 611 | // Returns 0 on success, -1 on failure. |
---|
| 612 | int NameToPort (const char * name, unsigned short * port, const char * proto) |
---|
| 613 | { |
---|
| 614 | unsigned long lport; |
---|
| 615 | char * errpos; |
---|
| 616 | struct servent * se; |
---|
| 617 | |
---|
| 618 | // First, attempt to convert string to integer |
---|
| 619 | lport = strtoul(name, &errpos, 0); |
---|
| 620 | if ( (*(errpos) == 0) && (lport <= 65535) ) // Success |
---|
| 621 | { |
---|
| 622 | *(port) = lport; |
---|
| 623 | return 0; |
---|
| 624 | } |
---|
| 625 | |
---|
| 626 | // Next, attempt to read the string from /etc/services |
---|
| 627 | se = getservbyname(name, proto); |
---|
| 628 | if ( se != NULL ) // Success |
---|
| 629 | { |
---|
| 630 | *(port) = ntohs(se->s_port); |
---|
| 631 | return 0; |
---|
| 632 | } |
---|
| 633 | |
---|
| 634 | return -1; // Failed to resolve port name to a number |
---|
| 635 | } |
---|
| 636 | |
---|
| 637 | // quit() |
---|
| 638 | // Print an error message to stderr |
---|
| 639 | // and syslog, then exit the program. |
---|
| 640 | void quit (const char *fmt, ...) // quit with msg |
---|
| 641 | { |
---|
| 642 | va_list ap; |
---|
| 643 | |
---|
| 644 | fflush(stdout); |
---|
| 645 | |
---|
| 646 | fprintf(stderr, "%s: ", g_program_name); |
---|
| 647 | |
---|
| 648 | va_start(ap, fmt); |
---|
| 649 | vfprintf(stderr, fmt, ap); |
---|
| 650 | va_end(ap); |
---|
| 651 | |
---|
| 652 | fputc('\n', stderr); |
---|
| 653 | |
---|
| 654 | syslog(LOG_ERR, "I quit!"); |
---|
| 655 | |
---|
| 656 | exit(EXIT_FAILURE); |
---|
| 657 | } |
---|
| 658 | |
---|
| 659 | // pbomb() |
---|
| 660 | // Print an error message to stderr |
---|
| 661 | // and syslog, then exit the program. |
---|
| 662 | // pbomb() additionally include the |
---|
| 663 | // string representation of errno. |
---|
| 664 | void pbomb (const char *fmt, ...) // bomb with perror |
---|
| 665 | { |
---|
| 666 | va_list ap; |
---|
| 667 | int errno_save = errno; |
---|
| 668 | char buf[100]; |
---|
| 669 | |
---|
| 670 | fflush(stdout); |
---|
| 671 | |
---|
| 672 | fprintf(stderr, "%s: ", g_program_name); |
---|
| 673 | |
---|
| 674 | va_start(ap, fmt); |
---|
| 675 | vsnprintf(buf, sizeof(buf), fmt, ap); |
---|
| 676 | va_end(ap); |
---|
| 677 | |
---|
| 678 | errno = errno_save; |
---|
| 679 | perror(buf); |
---|
| 680 | |
---|
| 681 | syslog(LOG_ERR, "Bang!: %s: %m", buf); |
---|
| 682 | |
---|
| 683 | exit(EXIT_FAILURE); |
---|
| 684 | } |
---|
| 685 | |
---|
| 686 | // hbomb() |
---|
| 687 | // Print an error message to stderr |
---|
| 688 | // and syslog, then exit the program. |
---|
| 689 | // hbomb() additionally include the |
---|
| 690 | // string representation of h_errno. |
---|
| 691 | void hbomb (const char *fmt, ...) // bomb with herror |
---|
| 692 | { |
---|
| 693 | va_list ap; |
---|
| 694 | int h_errno_save = h_errno; |
---|
| 695 | char buf[100]; |
---|
| 696 | |
---|
| 697 | fflush (stdout); |
---|
| 698 | |
---|
| 699 | fprintf (stderr, "%s: ", g_program_name); |
---|
| 700 | |
---|
| 701 | va_start(ap, fmt); |
---|
| 702 | vsnprintf(buf, sizeof(buf), fmt, ap); |
---|
| 703 | va_end(ap); |
---|
| 704 | |
---|
| 705 | h_errno = h_errno_save; |
---|
| 706 | herror(buf); |
---|
| 707 | |
---|
| 708 | syslog(LOG_ERR, "Bang!: %s: %s", buf, hstrerror(h_errno)); |
---|
| 709 | |
---|
| 710 | exit(EXIT_FAILURE); |
---|
| 711 | } |
---|
| 712 | |
---|
| 713 | // set_signal_handler() |
---|
| 714 | // Sets a signal handler function. |
---|
| 715 | // Similar to signal() but this method |
---|
| 716 | // is more portable between platforms. |
---|
| 717 | void set_signal_handler (int signum, signal_handler_t sa_handler_func) |
---|
| 718 | { |
---|
| 719 | struct sigaction act; |
---|
| 720 | |
---|
| 721 | act.sa_handler = sa_handler_func; |
---|
| 722 | sigemptyset (&(act.sa_mask)); |
---|
| 723 | act.sa_flags = 0; |
---|
| 724 | |
---|
| 725 | if ( sigaction(signum, &act, NULL) < 0 ) |
---|
| 726 | { |
---|
| 727 | syslog(LOG_ERR, "Error setting handler for signal %d: %m", signum); |
---|
| 728 | exit(EXIT_FAILURE); |
---|
| 729 | } |
---|
| 730 | } |
---|