106 lines
1.8 KiB
C
106 lines
1.8 KiB
C
#if !defined(lint) && defined(SCCSIDS)
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static char sccsid[] = "@(#)openchild.c 1.1 92/07/30 Copyr 1986 Sun Micro";
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#endif
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/*
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* openchild.c, Copyright (C) 1986 Sun Microsystems, Inc.
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*
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* Open two pipes to a child process, one for reading, one for writing.
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* The pipes are accessed by FILE pointers. This is NOT a public
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* interface, but for internal use only!
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*/
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#include <stdio.h>
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#include <vfork.h>
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extern char *malloc();
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extern char *strrchr();
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#ifndef S5EMUL
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extern char *sprintf();
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#endif
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static char *basename();
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static char *SHELL = "/bin/sh";
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/*
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* returns pid, or -1 for failure
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*/
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_openchild(command, fto, ffrom)
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char *command;
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FILE **fto;
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FILE **ffrom;
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{
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int i;
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int pid;
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int pdto[2];
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int pdfrom[2];
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char *com;
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if (pipe(pdto) < 0) {
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goto error1;
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}
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if (pipe(pdfrom) < 0) {
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goto error2;
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}
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switch (pid = vfork()) {
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case -1:
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goto error3;
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case 0:
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/*
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* child: read from pdto[0], write into pdfrom[1]
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*/
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(void) close(0);
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(void) dup(pdto[0]);
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(void) close(1);
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(void) dup(pdfrom[1]);
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for (i = _rpc_dtablesize() - 1; i >= 3; i--) {
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(void) close(i);
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}
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com = malloc((unsigned) strlen(command) + 6);
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if (com == NULL) {
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_exit(~0);
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}
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(void) sprintf(com, "exec %s", command);
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execl(SHELL, basename(SHELL), "-c", com, NULL);
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_exit(~0);
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default:
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/*
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* parent: write into pdto[1], read from pdfrom[0]
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*/
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*fto = fdopen(pdto[1], "w");
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(void) close(pdto[0]);
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*ffrom = fdopen(pdfrom[0], "r");
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(void) close(pdfrom[1]);
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break;
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}
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return (pid);
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/*
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* error cleanup and return
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*/
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error3:
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(void) close(pdfrom[0]);
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(void) close(pdfrom[1]);
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error2:
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(void) close(pdto[0]);
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(void) close(pdto[1]);
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error1:
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return (-1);
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}
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static char *
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basename(path)
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char *path;
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{
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char *p;
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p = strrchr(path, '/');
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if (p == NULL) {
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return (path);
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} else {
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return (p + 1);
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}
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}
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