1 files changed, 368 insertions, 0 deletions
diff --git a/exp_pty.c b/exp_pty.c
new file mode 100644
index 0000000..0970211
--- /dev/null
+++ b/exp_pty.c
@@ -0,0 +1,368 @@
+/* exp_pty.c - generic routines to allocate and test ptys
+
+Written by: Don Libes, NIST,  3/9/93
+
+Design and implementation of this program was paid for by U.S. tax
+dollars.  Therefore it is public domain.  However, the author and NIST
+would appreciate credit if this program or parts of it are used.
+
+*/
+
+#include "expect_cf.h"
+#ifdef HAVE_UNISTD_H
+#  include <unistd.h>
+#endif
+#ifdef HAVE_SYS_FCNTL_H
+#  include <sys/fcntl.h>
+#else
+#  include <fcntl.h>
+#endif
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#ifdef TIME_WITH_SYS_TIME
+# include <sys/time.h>
+# include <time.h>
+#else
+# if HAVE_SYS_TIME_H
+#  include <sys/time.h>
+# else
+#  include <time.h>
+# endif
+#endif
+
+#include <signal.h>
+#include <setjmp.h>
+#include <sys/file.h>
+#include "tcl.h"
+#include "exp_int.h"
+#include "expect_comm.h"
+#include "exp_rename.h"
+#include "exp_pty.h"
+
+#include <errno.h>
+
+#if 0
+void expDiagLog();
+void expDiagLogU();
+void expDiagLogPtrSet();
+#endif
+
+#ifndef TRUE
+#define TRUE 1
+#define FALSE 0
+#endif
+
+#ifdef O_NOCTTY
+#define RDWR ((O_RDWR)|(O_NOCTTY))
+#else
+#define RDWR O_RDWR
+#endif
+
+static int locked = FALSE;
+static char lock[] = "/tmp/ptylock.XXXX";	/* XX is replaced by pty id */
+static char locksrc[50] = "/tmp/expect.pid"; /* pid is replaced by real pid */
+	/* locksrc is used as the link source, i.e., something to link from */
+
+static int i_read_errno;/* place to save errno, if i_read() == -1, so it
+			   doesn't get overwritten before we get to read it */
+#ifdef HAVE_SIGLONGJMP
+static sigjmp_buf env;                /* for interruptable read() */
+#else
+static jmp_buf env;		/* for interruptable read() */
+#endif  /* HAVE_SIGLONGJMP */
+
+static int env_valid = FALSE;	/* whether we can longjmp or not */
+
+/* sigalarm_handler and i_read are here just for supporting the sanity */
+/* checking of pty slave devices.  I have only seen this happen on BSD */
+/* systems, but it may need to be done to the other pty implementations */
+/* as well. */
+
+/* Note that this code is virtually replicated from other code in expect */
+/* At some point, I'll dump one, but not until I'm satisfied no other */
+/* changes are needed */
+
+/*ARGSUSED*/
+static RETSIGTYPE
+sigalarm_handler(n)
+int n;		/* unused, for compatibility with STDC */
+{
+#ifdef REARM_SIG
+	signal(SIGALRM,sigalarm_handler);
+#endif
+
+	/* check env_valid first to protect us from the alarm occurring */
+	/* in the window between i_read and alarm(0) */
+#ifdef HAVE_SIGLONGJMP
+	if (env_valid) siglongjmp(env,1);
+#else
+	if (env_valid) longjmp(env,1);
+#endif  /* HAVE_SIGLONGJMP */
+}
+
+/* interruptable read */
+static int
+i_read(fd,buffer,length,timeout)
+int fd;
+char *buffer;
+int length;
+int timeout;
+{
+	int cc = -2;
+
+	/* since setjmp insists on returning 1 upon longjmp(,0), */
+	/* longjmp(,2) instead. */
+
+	/* restart read if setjmp returns 0 (first time) or 2. */
+	/* abort if setjmp returns 1. */
+
+	alarm(timeout);
+
+#ifdef HAVE_SIGLONGJMP
+	if (1 != sigsetjmp(env,1)) {
+#else
+	if (1 != setjmp(env)) {
+#endif  /* HAVE_SIGLONGJMP */
+		env_valid = TRUE;
+		cc = read(fd,buffer,length);
+	}
+	env_valid = FALSE;
+	i_read_errno = errno;	/* errno can be overwritten by the */
+				/* time we return */
+	alarm(0);
+	return(cc);
+}
+
+static RETSIGTYPE (*oldAlarmHandler)();
+static RETSIGTYPE (*oldHupHandler)();
+static time_t current_time;	/* time when testing began */
+
+/* if TRUE, begin testing, else end testing */
+/* returns -1 for failure, 0 for success */
+int
+exp_pty_test_start()
+{
+	int lfd;	/* locksrc file descriptor */
+
+	oldAlarmHandler = signal(SIGALRM,sigalarm_handler);
+#ifndef O_NOCTTY
+	/* Ignore hangup signals generated by pty testing */
+	/* when running in background with no control tty. */
+	/* Very few systems don't define O_NOCTTY.  Only one */
+	/* I know of is Next. */
+	oldAlarmHandler = signal(SIGHUP,SIG_IGN);
+#endif
+
+	time(&current_time);
+
+	/* recreate locksrc to prevent locks from 'looking old', so */
+	/* that they are not deleted (later on in this code) */
+	sprintf(locksrc,"/tmp/expect.%d",getpid());
+	(void) unlink(locksrc);
+	/* stanislav shalunov <shalunov@mccme.ru> notes that creat allows */
+	/* race - someone could link to important file which root could then */
+	/* smash. */
+/*	if (-1 == (lfd = creat(locksrc,0777))) { */
+       if (-1 == (lfd = open(locksrc,O_RDWR|O_CREAT|O_EXCL,0777))) {
+		static char buf[256];
+		exp_pty_error = buf;
+		sprintf(exp_pty_error,"can't create %s, errno = %d\n",locksrc, errno);
+		return(-1);
+	}
+	close(lfd);
+	return 0;
+}
+
+void
+exp_pty_test_end()
+{
+	signal(SIGALRM,oldAlarmHandler);
+#ifndef O_NOCTTY
+	signal(SIGALRM,oldHupHandler);
+#endif
+	(void) unlink(locksrc);
+}
+
+/* returns non-negative if successful */
+int
+exp_pty_test(
+     char *master_name,
+     char *slave_name,
+     char bank,
+     char *num)	/* string representation of number */
+{
+	int master, slave;
+	int cc;
+	char c;
+
+	/* make a lock file to prevent others (for now only */
+	/* expects) from allocating pty while we are playing */
+	/* with it.  This allows us to rigorously test the */
+	/* pty is usable. */
+	if (exp_pty_lock(bank,num) == 0) {
+		expDiagLogPtrStr("pty master (%s) is locked...skipping\r\n",master_name);
+		return(-1);
+	}
+	/* verify no one else is using slave by attempting */
+	/* to read eof from master side */
+	if (0 > (master = open(master_name,RDWR))) return(-1);
+
+#ifdef __QNX__
+
+	/* QNX ptys don't have a lot of the same properties such as
+           read 0 at EOF, etc */
+	/* if 1 should pacify C compiler without using nested ifdefs */
+ 	if (1) return master;
+#endif
+
+#ifdef HAVE_PTYTRAP
+	if (access(slave_name, R_OK|W_OK) != 0) {
+		expDiagLogPtrStr("could not open slave for pty master (%s)...skipping\r\n",
+			master_name);
+		(void) close(master);
+		return -1;
+	}
+	return(master);
+#else
+	if (0 > (slave = open(slave_name,RDWR))) {
+		(void) close(master);
+		return -1;
+	}
+	(void) close(slave);
+	cc = i_read(master,&c,1,10);
+	(void) close(master);
+	if (!(cc == 0 || cc == -1)) {
+		expDiagLogPtrStr("%s slave open, skipping\r\n",slave_name);
+		locked = FALSE;	/* leave lock file around so Expect's avoid */
+				/* retrying this pty for near future */
+		return -1;
+	}
+
+	/* verify no one else is using master by attempting */
+	/* to read eof from slave side */
+	if (0 > (master = open(master_name,RDWR))) return(-1);
+	if (0 > (slave = open(slave_name,RDWR))) {
+		(void) close(master);
+		return -1;
+	}
+	(void) close(master);
+	cc = i_read(slave,&c,1,10);
+	(void) close(slave);
+	if (!(cc == 0 || cc == -1)) {
+		expDiagLogPtrStr("%s master open, skipping\r\n",master_name);
+		return -1;
+	}
+
+	/* seems ok, let's use it */
+	expDiagLogPtrStr("using master pty %s\n",master_name);
+	return(open(master_name,RDWR));
+#endif
+}
+
+void
+exp_pty_unlock(void)
+{
+	if (locked) {
+		(void) unlink(lock);
+		locked = FALSE;
+	}
+}
+
+/* returns 1 if successfully locked, 0 otherwise */
+int
+exp_pty_lock(
+     char bank,
+     char *num)	/* string representation of number */
+{
+	struct stat statbuf;
+
+	if (locked) {
+		unlink(lock);
+		locked = FALSE;
+	}
+
+	sprintf(lock,"/tmp/ptylock.%c%s",bank,num);
+
+	if ((0 == stat(lock,&statbuf)) &&
+	    (statbuf.st_mtime+3600 < current_time)) {
+		(void) unlink(lock);
+	}
+
+	if (-1 == (link(locksrc,lock))) locked = FALSE;
+	else locked = TRUE;
+
+	return locked;
+}
+
+/* 
+ * expDiagLog needs a different definition, depending on whether its
+ * called inside of Expect or the clib.  Allow it to be set using this
+ * function.  It's done here because this file (and pty_XXX.c) are the 
+ * ones that call expDiagLog from the two different environments.
+ */
+
+static void		(*expDiagLogPtrVal) _ANSI_ARGS_((char *));
+
+void
+expDiagLogPtrSet(fn)
+     void (*fn) _ANSI_ARGS_((char *));
+{
+  expDiagLogPtrVal = fn;
+}
+
+void
+expDiagLogPtr(str)
+     char *str;
+{
+  (*expDiagLogPtrVal)(str);
+}
+
+
+
+void
+expDiagLogPtrX(fmt,num)
+     char *fmt;
+     int num;
+{
+  static char buf[1000];
+  sprintf(buf,fmt,num);
+  (*expDiagLogPtrVal)(buf);
+}
+
+
+void
+expDiagLogPtrStr(fmt,str1)
+     char *fmt;
+     char *str1;
+{
+  static char buf[1000];
+  sprintf(buf,fmt,str1);
+  (*expDiagLogPtrVal)(buf);
+}
+
+void
+expDiagLogPtrStrStr(fmt,str1,str2)
+     char *fmt;
+     char *str1, *str2;
+{
+  static char buf[1000];
+  sprintf(buf,fmt,str1,str2);
+  (*expDiagLogPtrVal)(buf);
+}
+
+static char *		(*expErrnoMsgVal) _ANSI_ARGS_((int));
+
+char *
+expErrnoMsg(errorNo)
+int errorNo;
+{
+  return (*expErrnoMsgVal)(errorNo);
+}
+
+void
+expErrnoMsgSet(fn)
+     char * (*fn) _ANSI_ARGS_((int));
+{
+  expErrnoMsgVal = fn;
+}