[1484] | 1 | /* This file is part of the Project Athena Global Message System. |
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| 2 | * Created by: Mark W. Eichin <eichin@athena.mit.edu> |
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| 3 | * $Source: /afs/dev.mit.edu/source/repository/athena/bin/gms/get_message_from_server.c,v $ |
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| 4 | * $Author: eichin $ |
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| 5 | * |
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| 6 | * Copyright (c) 1988 by the Massachusetts Institute of Technology. |
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| 7 | * For copying and distribution information, see the file |
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| 8 | * "mit-copyright.h". |
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| 9 | */ |
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| 10 | #include <mit-copyright.h> |
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| 11 | #ifndef lint |
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| 12 | static char rcsid_get_message_from_server_c[] = "$Header: /afs/dev.mit.edu/source/repository/athena/bin/gms/get_message_from_server.c,v 1.1 1988-09-26 15:40:43 eichin Exp $"; |
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| 13 | #endif lint |
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| 14 | |
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| 15 | #include "globalmessage.h" |
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| 16 | #include <sys/types.h> |
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| 17 | #include <sys/socket.h> |
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| 18 | #include <netinet/in.h> |
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| 19 | #include <netdb.h> |
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| 20 | #include <hesiod.h> |
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| 21 | #include <sys/time.h> |
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| 22 | |
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| 23 | Code_t get_message_from_server(ret_message, ret_message_size, server) |
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| 24 | char **ret_message; |
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| 25 | int *ret_message_size; |
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| 26 | char *server; |
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| 27 | { |
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| 28 | struct sockaddr_in server_insocket; |
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| 29 | int sck, stat; |
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| 30 | char *message_data; |
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| 31 | int message_size; |
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| 32 | |
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| 33 | /* guard against NULL arguments */ |
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| 34 | if ((!ret_message)||(!server)) { |
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| 35 | return(GMS_NULL_ARG_ERR); |
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| 36 | } |
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| 37 | |
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| 38 | /* contact the server, send the request name, get the message back */ |
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| 39 | /* create the socket */ |
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| 40 | sck = socket(AF_INET, SOCK_DGRAM, 0); /* 0 is VERY special... */ |
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| 41 | if(sck == -1) { |
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| 42 | /* handle socket error */ |
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| 43 | return(errno); |
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| 44 | } |
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| 45 | |
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| 46 | /* Set the socket family */ |
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| 47 | server_insocket.sin_family = AF_INET; |
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| 48 | |
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| 49 | /* Set the socket port */ |
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| 50 | { |
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| 51 | struct servent *gms_service, *hes_getservbyname(); |
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| 52 | gms_service = getservbyname(GMS_SERV_NAME, GMS_SERV_PROTO); |
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| 53 | if(!gms_service) { |
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| 54 | /* getservbyname failed, fall back... */ |
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| 55 | /* Note that hes_getservbyname is broken currently, and does not |
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| 56 | * convert the service name to host byte order. This should be |
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| 57 | * fixed in the library; it will not be fixed here, since that |
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| 58 | * will make it break later. |
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| 59 | */ |
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| 60 | gms_service = hes_getservbyname(GMS_SERV_NAME, GMS_SERV_PROTO); |
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| 61 | if(!gms_service) { |
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| 62 | /* so did getservbyname, fall back to hard coded? */ |
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| 63 | return(GMS_NO_SERVICE_NAME); |
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| 64 | } |
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| 65 | } |
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| 66 | server_insocket.sin_port = gms_service->s_port; |
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| 67 | } |
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| 68 | |
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| 69 | /* Set the socket address */ |
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| 70 | { |
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| 71 | struct hostent *gms_host; |
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| 72 | gms_host = gethostbyname(server); |
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| 73 | if(!gms_host) { |
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| 74 | /* gethostbyname failed */ |
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| 75 | return(gethost_error()); |
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| 76 | } |
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| 77 | /* Copy in the first (preferred?) address of the server */ |
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| 78 | bcopy(gms_host->h_addr_list[0], &server_insocket.sin_addr, |
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| 79 | gms_host->h_length); |
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| 80 | } |
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| 81 | |
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| 82 | /* Actually make the connection */ |
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| 83 | { |
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| 84 | stat = connect(sck, &server_insocket, sizeof(server_insocket)); |
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| 85 | if(stat == -1) { |
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| 86 | /* handle connect error */ |
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| 87 | return(errno); |
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| 88 | } |
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| 89 | } |
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| 90 | |
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| 91 | /* send the version string as a datagram */ |
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| 92 | stat = send(sck, GMS_VERSION_STRING, GMS_VERSION_STRING_LEN, 0); |
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| 93 | if (stat == -1) { |
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| 94 | /* handle send failed error */ |
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| 95 | return(errno); |
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| 96 | } |
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| 97 | |
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| 98 | /* set up a timeout and select on the socket, to catch the return |
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| 99 | * packet */ |
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| 100 | { |
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| 101 | fd_set reader; |
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| 102 | struct timeval timer; |
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| 103 | |
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| 104 | FD_ZERO(&reader); |
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| 105 | FD_SET(sck, &reader); |
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| 106 | |
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| 107 | timer.tv_sec = GMS_TIMEOUT_SEC; |
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| 108 | timer.tv_usec = GMS_TIMEOUT_USEC; |
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| 109 | |
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| 110 | stat = select(sck+1, &reader, 0, 0, &timer); |
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| 111 | if (stat == -1) { |
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| 112 | return(errno); |
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| 113 | } |
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| 114 | if (stat == 0) { |
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| 115 | return(GMS_TIMED_OUT); |
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| 116 | } |
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| 117 | /* since we only wait on reader, it must have arrived */ |
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| 118 | } |
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| 119 | |
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| 120 | message_data = malloc(GMS_MAX_MESSAGE_LEN); |
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| 121 | stat = recv(sck, message_data, GMS_MAX_MESSAGE_LEN, 0); |
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| 122 | |
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| 123 | close(sck); /* regardless of any errors... */ |
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| 124 | |
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| 125 | if(stat == -1) { |
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| 126 | free(*message_data); |
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| 127 | return(errno); |
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| 128 | } |
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| 129 | |
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| 130 | *ret_message_size = stat; |
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| 131 | *ret_message = message_data; |
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| 132 | return(0); |
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| 133 | } |
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