87 lines
2.0 KiB
C
87 lines
2.0 KiB
C
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/* userver.c - simple server for Unix domain sockets */
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/* Waits for a connection on the ./sample-socket Unix domain
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socket. Once a connection has been established, copy data
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from the socket to stdout until the other end closes the
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connection, and then wait for another connection to the socket. */
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#include <stdio.h>
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#include <sys/socket.h>
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#include <sys/un.h>
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#include <unistd.h>
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#define _PATH_LOG "/dev/log"
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/* issue an error message via perror() and terminate the program */
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void die(char * message) {
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perror(message);
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exit(1);
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}
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/* Copies data from file descriptor 'from' to file descriptor 'to'
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until nothing is left to be copied. Exits if an error occurs. */
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void copyData(int from, int to) {
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char buf[1024];
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int amount;
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while ((amount = read(from, buf, sizeof(buf))) > 0) {
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if (write(to, buf, amount) != amount) {
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die("write");
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return;
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}
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}
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if (amount < 0)
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die("read");
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}
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int main(void) {
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struct sockaddr_un address;
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int fd, conn;
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size_t addrLength;
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/* Remove any preexisting socket (or other file) */
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unlink(_PATH_LOG);
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memset(&address, 0, sizeof(address));
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address.sun_family = AF_UNIX; /* Unix domain socket */
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strncpy(address.sun_path, _PATH_LOG, sizeof(address.sun_path));
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if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
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die("socket");
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/* The total length of the address includes the sun_family
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element */
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addrLength = sizeof(address.sun_family) +
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strlen(address.sun_path);
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if (bind(fd, (struct sockaddr *) &address, addrLength))
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die("bind");
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if (chmod(_PATH_LOG, 0666) < 0)
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die("chmod");
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if (listen(fd, 5))
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die("listen");
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while ((conn = accept(fd, (struct sockaddr *) &address,
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&addrLength)) >= 0) {
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printf("---- getting data\n");
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copyData(conn, fileno(stdout));
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printf("---- done\n");
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close(conn);
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}
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if (conn < 0)
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die("accept");
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close(fd);
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return 0;
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}
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