Import the latest version of the 44BSD C-shell -- tcsh-6.09.

1 files changed, 206 insertions, 0 deletions

diff --git a/contrib/tcsh/tw.help.c b/contrib/tcsh/tw.help.c
new file mode 100644
index 0000000..87c691d
--- /dev/null
+++ b/contrib/tcsh/tw.help.c
@@ -0,0 +1,206 @@
+/* $Header: /src/pub/tcsh/tw.help.c,v 3.16 1999/05/11 13:08:03 christos Exp $ */
+/* tw.help.c: actually look up and print documentation on a file.
+ *	      Look down the path for an appropriate file, then print it.
+ *	      Note that the printing is NOT PAGED.  This is because the
+ *	      function is NOT meant to look at manual pages, it only does so
+ *	      if there is no .help file to look in.
+ */
+/*-
+ * Copyright (c) 1980, 1991 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#include "sh.h"
+
+RCSID("$Id: tw.help.c,v 3.16 1999/05/11 13:08:03 christos Exp $")
+
+#include "tw.h"
+#include "tc.h"
+
+
+static int f = -1;
+static	sigret_t	 cleanf		__P((int));
+static	Char    	*skipslist	__P((Char *));
+static	void		 nextslist 	__P((Char *, Char *));
+
+static char *h_ext[] = {
+    ".help", ".1", ".8", ".6", "", NULL
+};
+
+void
+do_help(command)
+    Char   *command;
+{
+    Char    name[FILSIZ + 1];
+    Char   *cmd_p, *ep;
+    char  **sp;
+
+    signalfun_t orig_intr;
+    Char    curdir[MAXPATHLEN];	/* Current directory being looked at */
+    register Char *hpath;	/* The environment parameter */
+    Char    full[MAXPATHLEN];
+    char    buf[512];		/* full path name and buffer for read */
+    int     len;		/* length of read buffer */
+    Char   *thpath;
+
+
+    /* trim off the whitespace at the beginning */
+    for (cmd_p = command; *cmd_p == ' ' || *cmd_p == '\t'; cmd_p++)
+	continue;
+		
+    /* copy the string to a safe place */
+    copyn(name, cmd_p, FILSIZ + 1);
+
+    /* trim off the whitespace that may be at the end */
+    for (cmd_p = name; 
+	 *cmd_p != ' ' && *cmd_p != '\t' && *cmd_p != '\0'; cmd_p++)
+	continue;
+    *cmd_p = '\0';
+
+    /* if nothing left, return */
+    if (*name == '\0')
+	return;
+
+    if (adrof1(STRhelpcommand, &aliases)) {	/* if we have an alias */
+	jmp_buf_t osetexit;
+
+	getexit(osetexit);	/* make sure to come back here */
+	if (setexit() == 0)
+	    aliasrun(2, STRhelpcommand, name);	/* then use it. */
+	resexit(osetexit);	/* and finish up */
+    }
+    else {			/* else cat something to them */
+	/* got is, now "cat" the file based on the path $HPATH */
+
+	hpath = str2short(getenv(SEARCHLIST));
+	if (hpath == NULL)
+	    hpath = str2short(DEFAULTLIST);
+	thpath = hpath = Strsave(hpath);
+
+	for (;;) {
+	    if (!*hpath) {
+		xprintf(CGETS(29, 1, "No help file for %S\n"), name);
+		break;
+	    }
+	    nextslist(hpath, curdir);
+	    hpath = skipslist(hpath);
+
+	    /*
+	     * now make the full path name - try first /bar/foo.help, then
+	     * /bar/foo.1, /bar/foo.8, then finally /bar/foo.6.  This is so
+	     * that you don't spit a binary at the tty when $HPATH == $PATH.
+	     */
+	    copyn(full, curdir, (int) (sizeof(full) / sizeof(Char)));
+	    catn(full, STRslash, (int) (sizeof(full) / sizeof(Char)));
+	    catn(full, name, (int) (sizeof(full) / sizeof(Char)));
+	    ep = &full[Strlen(full)];
+	    for (sp = h_ext; *sp; sp++) {
+		*ep = '\0';
+		catn(full, str2short(*sp), (int) (sizeof(full) / sizeof(Char)));
+		if ((f = open(short2str(full), O_RDONLY)) != -1)
+		    break;
+	    }
+	    if (f != -1) {
+		/* so cat it to the terminal */
+		orig_intr = (signalfun_t) sigset(SIGINT, cleanf);
+		while (f != -1 && (len = read(f, (char *) buf, 512)) > 0)
+		    (void) write(SHOUT, (char *) buf, (size_t) len);
+#ifdef convex
+		/* print error in case file is migrated */
+		if (len == -1)
+		    stderror(ERR_SYSTEM, progname, strerror(errno));
+#endif /* convex */
+		(void) sigset(SIGINT, orig_intr);
+		if (f != -1)
+		    (void) close(f);
+		break;
+	    }
+	}
+	xfree((ptr_t) thpath);
+    }
+}
+
+static  sigret_t
+/*ARGSUSED*/
+cleanf(snum)
+int snum;
+{
+#ifdef UNRELSIGS
+    if (snum)
+	(void) sigset(SIGINT, cleanf);
+#endif /* UNRELSIGS */
+    if (f != -1)
+	(void) close(f);
+    f = -1;
+#ifndef SIGVOID
+    return (snum);
+#endif
+}
+
+/* these next two are stolen from CMU's man(1) command for looking down
+ * paths.  they are prety straight forward. */
+
+/*
+ * nextslist takes a search list and copies the next path in it
+ * to np.  A null search list entry is expanded to ".".
+ * If there are no entries in the search list, then np will point
+ * to a null string.
+ */
+
+static void
+nextslist(sl, np)
+    register Char *sl;
+    register Char *np;
+{
+    if (!*sl)
+	*np = '\000';
+    else if (*sl == ':') {
+	*np++ = '.';
+	*np = '\000';
+    }
+    else {
+	while (*sl && *sl != ':')
+	    *np++ = *sl++;
+	*np = '\000';
+    }
+}
+
+/*
+ * skipslist returns the pointer to the next entry in the search list.
+ */
+
+static Char *
+skipslist(sl)
+    register Char *sl;
+{
+    while (*sl && *sl++ != ':')
+	continue;
+    return (sl);
+}