add directory study

study/linux-travel/MINIX-1.5/1.5/Source/amoeba/util/rsh.c

@@ -0,0 +1,245 @@
+/*	rsh [-ei] machine command
+ *
+ *	-b:	run remote process in background
+ *	-e:	separate error output
+ *	-i:	send input
+ */
+
+#include <stdio.h>
+#include <signal.h>
+#include "amoeba.h"
+#include "sherver.h"
+
+char *prog, *mach, buf[BUFFERSIZE];
+
+usage(){
+	fprintf(stderr, "Usage: %s [-bei] machine command ...\n", prog);
+	exit(1);
+}
+
+panic(s)
+char *s;
+{
+	fprintf(stderr, "%s: %s\n", prog, s);
+	exit(1);
+}
+
+char *collect(buf, vec, sep)
+char *buf, **vec, sep;
+{
+	register char *p;
+
+	while ((p = *vec++) != 0) {
+		while (*p != 0) {
+			*buf++ = *p++;
+			if (buf == &buf[BUFFERSIZE])
+				panic("environment too large\n");
+		}
+		*buf++ = *vec == 0 ? 0 : sep;
+	}
+	return(buf);
+}
+
+char *setupbuf(argv, flags)
+char **argv;
+int *flags;
+{
+	register char *p;
+	extern char **environ, *getenv();
+
+	if (*argv == 0) {
+		if ((p = getenv("SHELL")) == 0)
+			p = "/bin/sh";
+		if (strlen(p) > BUFFERSIZE - 10) /* 10 > strlen("exec  -i") */
+			panic("pathname of shell too large");
+		sprintf(buf, "exec %s -i", p);
+		p = &buf[strlen(buf) + 1];
+		*flags |= IFLG;
+	}
+	else
+		p = collect(buf, argv, ' ');
+	return collect(p, environ, 0);
+}
+
+execute(hdr, p, flags)
+header *hdr;
+char *p;
+{
+	register unshort cnt;
+
+	timeout(50);
+	strncpy(&hdr->h_port, mach, PORTSIZE);
+	hdr->h_command = EXEC_COMMAND;
+	hdr->h_size = p - buf;
+	hdr->h_extra = flags;
+	cnt = trans(hdr, buf, p - buf, hdr, buf, BUFFERSIZE);
+	if ((short) cnt < 0) {
+		fprintf(stderr, "%s: %s not available\n", prog, mach);
+		return(0);
+	}
+	if (hdr->h_status != COMM_DONE) {
+		if (cnt == 0)
+			fprintf(stderr, "can't execute command\n");
+		else
+			fprintf(stderr, "%.*s\n", cnt, buf);
+		return(0);
+	}
+	return(1);
+}
+
+alrm(){
+	fprintf(stderr, "rsh: getreq timed out\n");
+	exit(1);
+}
+
+commandloop(hdr)
+header *hdr;
+{
+	register unshort cnt;
+
+	for (;;) {
+		alarm(12*60*60);
+		cnt = getreq(hdr, buf, BUFFERSIZE);
+		alarm(0);
+		if ((short) cnt < 0) {
+			fprintf(stderr, "getreq failed\n");
+			return(-1);
+		}
+		switch (hdr->h_command) {
+		case READ_FD:
+			if (hdr->h_extra < NFD)
+				cnt = read(hdr->h_extra, buf, hdr->h_size);
+			else
+				fprintf(stderr, "read: bad fd\n");
+			hdr->h_size = (unshort) cnt;
+			putrep(hdr, buf, cnt < 0 ? 0 : cnt);
+			if (cnt == 0)
+				return(0);
+			break;
+		case WRITE_FD:
+			if (hdr->h_extra < NFD)
+				if (cnt == 0)
+					close(hdr->h_extra);
+				else
+					write(hdr->h_extra, buf, cnt);
+			else
+				fprintf(stderr, "write: bad fd\n");
+			putrep(hdr, NILBUF, 0);
+			break;
+		case EXIT_STATUS:
+			if (cnt != 0) {
+				write(2, "Remote message: ", 16);
+				write(2, buf, cnt);
+				write(2, "\n", 1);
+			}
+			putrep(hdr, NILBUF, 0);
+			return(hdr->h_extra >> 8);
+			break;
+		default:
+			fprintf(stderr, "unknown command\n");
+			putrep(hdr, NILBUF, 0);
+		}
+	}
+}
+
+setupin(hdr)
+header *hdr;
+{
+	register pid;
+
+	uniqport(&hdr->h_priv.prv_random);
+	if ((pid = fork()) < 0) {
+		perror(prog);
+		exit(-1);
+	}
+	if (pid == 0) {
+		hdr->h_port = hdr->h_priv.prv_random;
+		_exit(commandloop(hdr));   /* get read commands from sherver */
+	}
+	return(pid);
+}
+
+main(argc, argv)
+char **argv;
+{
+	char *p;
+	header hdr;
+	register pid, status;
+	int flags;
+
+#ifdef sun
+	put_user_name_in_env();
+#endif
+	prog = *argv++;
+	if (argc == 1)
+		usage();
+	signal(SIGALRM, alrm);
+	while (*argv != 0 && **argv == '-') {
+		while (*++*argv)
+			switch (**argv) {
+			case 'b':	flags |= BFLG;		break;
+			case 'e':	flags |= EFLG;		break;
+			case 'i':	flags |= IFLG;		break;
+			default:	usage();
+			}
+		argv++;
+	}
+	if ((mach = *argv++) == 0)
+		usage();
+	chkperm(mach);
+	p = setupbuf(argv, &flags);	/* get command and environment */
+	if (flags & IFLG)		/* set up input process */
+		pid = setupin(&hdr);
+	if (!execute(&hdr, p, flags)) {	/* send command to sherver */
+		if (flags & IFLG)
+			kill(pid, SIGKILL);
+		exit(1);
+	}
+	if (!(flags & BFLG))		/* get commands from sherver */
+		status = commandloop(&hdr);
+	if (flags & IFLG) {		/* wait for input process */
+		close(0); close(1); close(2);
+		while (wait((int *) 0) != pid)
+			;
+	}
+	exit(status);
+}
+
+chkperm(svport)
+char *svport;
+{
+	static char chkfil[] = "/etc/XXXXXXXXXXXXXX";
+	extern char *strchr();
+
+	sprintf(strchr(chkfil, 'X'), "rsh:%.14s", svport);
+	if (chkprot(chkfil, "/etc/rsh:default", geteuid(), getegid()) == 0)
+		panic("permission denied");
+}
+
+char *strchr(s, c)
+register char *s;
+{
+	while (*s) {
+		if (*s == c)
+			return s;
+		s++;
+	}
+	return 0;
+}
+
+#ifdef sun
+#include <pwd.h>
+
+put_user_name_in_env()
+{
+	extern struct passwd *getpwuid();
+	register struct passwd *pw;
+	static char buf[512];
+	char host[10];
+
+	gethostname(host, sizeof host);
+	pw = getpwuid(getuid());
+	sprintf(buf, "UserName=%s@%s", pw ? pw->pw_name : "???", host);
+	putenv(buf);
+}
+#endif sun