49 lines
867 B
C
49 lines
867 B
C
/*
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* inet/bindresvport.c
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*/
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#include <errno.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <netinet/in.h>
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#include <string.h>
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#include <unistd.h>
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#define START_PORT 600
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#define END_PORT (IPPORT_RESERVED - 1)
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#define NUM_PORTS (END_PORT - START_PORT)
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int bindresvport(int sd, struct sockaddr_in *sin)
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{
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struct sockaddr_in me;
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static short port;
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int ret = 0;
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int i;
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if (sin == NULL) {
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sin = &me;
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memset(sin, 0, sizeof(me));
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sin->sin_port = AF_INET;
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}
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else if (sin->sin_family != AF_INET) {
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errno = EPFNOSUPPORT;
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ret = -1;
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goto bail;
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}
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if (port == 0) {
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port = START_PORT + (getpid() % NUM_PORTS);
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}
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for (i = 0; i < NUM_PORTS; i++, port++) {
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sin->sin_port = htons(port);
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if ((ret = bind(sd, (struct sockaddr *)&sin, sizeof(*sin))) != -1)
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break;
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if (port == END_PORT)
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port = START_PORT;
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}
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bail:
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return ret;
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}
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