/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2001 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 * Copyright (c) 2016 by Delphix. All rights reserved.
 */

/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

/*
 * mailx -- a modified version of a University of California at Berkeley
 *	mail program
 *
 * Handle name lists.
 */

#include "rcv.h"
#include <locale.h>

static struct name	*nalloc(char str[]);
static int		isfileaddr(char *name);
static int		lengthof(struct name *name);
static struct name	*gexpand(struct name *nlist, struct grouphead *gh,
    int metoo, int arg_ntype);
static char		*norm(register char *user, register char *ubuf,
    int nbangs);
static struct name	*put(struct name *list, struct name *node);

/*
 * Allocate a single element of a name list,
 * initialize its name field to the passed
 * name and return it.
 */

static struct name *
nalloc(char str[])
{
	register struct name *np;

	np = (struct name *)salloc(sizeof (*np));
	np->n_flink = NIL;
	np->n_blink = NIL;
	np->n_type = -1;
	np->n_full = savestr(str);
	np->n_name = skin(np->n_full);
	return (np);
}

/*
 * Find the tail of a list and return it.
 */

struct name *
tailof(struct name *name)
{
	register struct name *np;

	np = name;
	if (np == NIL)
		return (NIL);
	while (np->n_flink != NIL)
		np = np->n_flink;
	return (np);
}

/*
 * Extract a list of names from a line,
 * and make a list of names from it.
 * Return the list or NIL if none found.
 */

struct name *
extract(char line[], int arg_ntype)
{
	short ntype = (short)arg_ntype;
	register char *cp;
	register struct name *top, *np, *t;
	char nbuf[BUFSIZ], abuf[BUFSIZ];
	int comma;

	if (line == NOSTR || strlen(line) == 0)
		return (NIL);
	comma = docomma(line);
	top = NIL;
	np = NIL;
	cp = line;
	while ((cp = yankword(cp, nbuf, sizeof (nbuf), comma)) != NOSTR) {
		if (np != NIL && equal(nbuf, "at")) {
			nstrcpy(abuf, sizeof (abuf), nbuf);
			if ((cp = yankword(cp, nbuf, sizeof (nbuf),
			    comma)) == NOSTR) {
				nstrcpy(nbuf, sizeof (nbuf), abuf);
				goto normal;
			}
			snprintf(abuf, sizeof (abuf), "%s@%s", np->n_name,
			    nbuf);
			np->n_name = savestr(abuf);
			continue;
		}
normal:
		t = nalloc(nbuf);
		t->n_type = ntype;
		if (top == NIL)
			top = t;
		else
			np->n_flink = t;
		t->n_blink = np;
		np = t;
	}
	return (top);
}

/*
 * Turn a list of names into a string of the same names.
 */

char *
detract(register struct name *np, int ntype)
{
	register int s;
	register char *cp, *top;
	register struct name *p;

	if (np == NIL)
		return (NOSTR);
	s = 0;
	for (p = np; p != NIL; p = p->n_flink) {
		if ((ntype && (p->n_type & GMASK) != ntype) ||
		    (p->n_type & GDEL))
			continue;
		s += strlen(p->n_full) + 2;
	}
	if (s == 0)
		return (NOSTR);
	top = (char *)salloc((unsigned)(++s));
	cp = top;
	for (p = np; p != NIL; p = p->n_flink) {
		if ((ntype && (p->n_type & GMASK) != ntype) ||
		    (p->n_type & GDEL))
			continue;
		cp = copy(p->n_full, cp);
		*cp++ = ',';
		*cp++ = ' ';
	}
	*cp = 0;
	return (top);
}

struct name *
outpre(struct name *to)
{
	register struct name *np;

	for (np = to; np; np = np->n_flink)
		if (isfileaddr(np->n_name))
			np->n_type |= GDEL;
	return (to);
}

/*
 * For each recipient in the passed name list with a /
 * in the name, append the message to the end of the named file
 * and remove them from the recipient list.
 *
 * Recipients whose name begins with | are piped through the given
 * program and removed.
 */

int
outof(struct name *names, FILE *fo)
{
	register int c;
	register struct name *np;
	time_t now;
	char *date, *fname, *shell;
	FILE *fout, *fin;
	int ispipe;
	int nout = 0;
	int fd = 0;
#ifdef preSVr4
	char line[BUFSIZ];
#endif

	if (value("expandaddr") == NOSTR)
		return (nout);

	for (np = names; np != NIL; np = np->n_flink) {
		if (!isfileaddr(np->n_name) && np->n_name[0] != '|')
			continue;
		nout++;
		ispipe = np->n_name[0] == '|';
		if (ispipe)
			fname = np->n_name+1;
		else
			fname = safeexpand(np->n_name);

		/*
		 * See if we have copied the complete message out yet.
		 * If not, do so.
		 */

		if (image < 0) {
			fd = open(tempEdit, O_CREAT|O_EXCL|O_APPEND|O_WRONLY,
			    0600);
			if ((fd  < 0) && (errno == EEXIST)) {
				if ((fd = open(tempEdit, O_APPEND|O_WRONLY,
				    0600)) < 0) {
					perror(tempEdit);
					senderr++;
					goto cant;
				}
			}
			if ((fout = fdopen(fd, "a")) == NULL) {
				perror(tempEdit);
				senderr++;
				goto cant;
			}
			image = open(tempEdit, O_RDWR);
			unlink(tempEdit);
			if (image < 0) {
				perror(tempEdit);
				senderr++;
				goto cant;
			} else {
				rewind(fo);
				time(&now);
				date = ctime(&now);
				fprintf(fout, "From %s %s", myname, date);
				while ((c = getc(fo)) != EOF)
					putc(c, fout);
				rewind(fo);
				fflush(fout);
				if (fferror(fout))
					perror(tempEdit);
				fclose(fout);
			}
		}

		/*
		 * Now either copy "image" to the desired file
		 * or give it as the standard input to the desired
		 * program as appropriate.
		 */

		if (ispipe) {
			wait((int *)NULL);
			switch (fork()) {
			case 0:
				sigchild();
				sigset(SIGHUP, SIG_IGN);
				sigset(SIGINT, SIG_IGN);
				sigset(SIGQUIT, SIG_IGN);
				close(0);
				dup(image);
				close(image);
				lseek(0, 0L, 0);
				if ((shell = value("SHELL")) == NOSTR ||
				    *shell == '\0')
					shell = SHELL;
				(void) execlp(shell, shell, "-c", fname,
				    (char *)0);
				perror(shell);
				exit(1);
				break;

			case (pid_t)-1:
				perror("fork");
				senderr++;
				goto cant;
			}
		} else {
			if ((fout = fopen(fname, "a")) == NULL) {
				perror(fname);
				senderr++;
				goto cant;
			}
			fin = Fdopen(image, "r");
			if (fin == NULL) {
				fprintf(stderr,
				    gettext("Can't reopen image\n"));
				fclose(fout);
				senderr++;
				goto cant;
			}
			rewind(fin);
#ifdef preSVr4
			putc(getc(fin), fout);
			while (fgets(line, sizeof (line), fin)) {
				if (strncmp(line, "From ", 5) == 0)
					putc('>', fout);
				fputs(line, fout);
			}
#else
			while ((c = getc(fin)) != EOF)
				putc(c, fout);
#endif
			putc('\n', fout);
			fflush(fout);
			if (fferror(fout))
				senderr++, perror(fname);
			fclose(fout);
			fclose(fin);
		}
cant:
		/*
		 * In days of old we removed the entry from the
		 * the list; now for sake of header expansion
		 * we leave it in and mark it as deleted.
		 */

#ifdef CRAZYWOW
		{
		register struct name *t, *x;

		if (np == top) {
			top = np->n_flink;
			if (top != NIL)
				top->n_blink = NIL;
			np = top;
			continue;
		}
		x = np->n_blink;
		t = np->n_flink;
		x->n_flink = t;
		if (t != NIL)
			t->n_blink = x;
		np = t;
		}
#endif

		np->n_type |= GDEL;
	}
	if (image >= 0) {
		close(image);
		image = -1;
	}
	return (nout);
}

/*
 * Determine if the passed address is a local "send to file" address.
 * If any of the network metacharacters precedes any slashes, it can't
 * be a filename.  We cheat with .'s to allow path names like ./...
 * If "fcc" has been unset, then short-circuit those tests, but not
 * the +... test.
 */
static int
isfileaddr(char *name)
{
	register char *cp;
	char *fcc = value("fcc");

	if (any('@', name))
		return (0);
	if (*name == '+')
		return (1);
	if (fcc == NOSTR)
		return (0);
	for (cp = name; *cp; cp++) {
		if (*cp == '.')
			continue;
		if (any(*cp, metanet))
			return (0);
		if (*cp == '/')
			return (1);
	}
	return (0);
}

/*
 * Map all of the aliased users in the invoker's mailrc
 * file and insert them into the list.
 * Changed after all these months of service to recursively
 * expand names (2/14/80).
 */

struct name *
usermap(struct name *names)
{
	register struct name *newnames, *np, *cp;
	struct grouphead *gh;
	register int metoo;

	newnames = NIL;
	np = names;
	metoo = (value("metoo") != NOSTR);
	while (np != NIL) {
		if (np->n_name[0] == '\\') {
			cp = np->n_flink;
			newnames = put(newnames, np);
			np = cp;
			continue;
		}
		gh = findgroup(np->n_name);
		cp = np->n_flink;
		if (gh != NOGRP)
			newnames = gexpand(newnames, gh, metoo, np->n_type);
		else
			newnames = put(newnames, np);
		np = cp;
	}
	return (newnames);
}

/*
 * Recursively expand a group name.  We limit the expansion to some
 * fixed level to keep things from going haywire.
 * Direct recursion is not expanded for convenience.
 */

static struct name *
gexpand(struct name *nlist, struct grouphead *gh, int metoo, int arg_ntype)
{
	short ntype = (short)arg_ntype;
	struct mgroup *gp;
	struct grouphead *ngh;
	struct name *np;
	static int depth;
	register char *cp;

	if (depth > MAXEXP) {
		printf(gettext("Expanding alias to depth larger than %d\n"),
		    MAXEXP);
		return (nlist);
	}
	depth++;
	for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link) {
		cp = gp->ge_name;
		if (*cp == '\\')
			goto quote;
		if (strcmp(cp, gh->g_name) == 0)
			goto quote;
		if ((ngh = findgroup(cp)) != NOGRP) {
			nlist = gexpand(nlist, ngh, metoo, ntype);
			continue;
		}
quote:
		np = nalloc(cp);
		np->n_type = ntype;
		/*
		 * At this point should allow to expand
		 * to self if only person in group
		 */
		if (gp == gh->g_list && gp->ge_link == NOGE)
			goto skip;
		if (!metoo && samebody(myname, gp->ge_name, FALSE))
			np->n_type |= GDEL;
skip:
		nlist = put(nlist, np);
	}
	depth--;
	return (nlist);
}

/*
 * Normalize a network name for comparison purposes.
 */
static char *
norm(register char *user, register char *ubuf, int nbangs)
{
	register char *cp;
	int inubuf = 0;

	while (*user++ == '!')
		;
	user--;
	if (!strchr(user, '!')) {
		snprintf(ubuf, BUFSIZ, "%s!%s", host, user);
		user = ubuf;
		inubuf++;
	}
	if (nbangs) {
		cp = user + strlen(user);
		while (nbangs--)
			while (cp > user && *--cp != '!')
				;
		user = (cp > user) ? ++cp : cp;
		/*
		 * Now strip off all Internet-type
		 * hosts.
		 */
		if ((cp = strchr(user, '%')) == NOSTR)
			cp = strchr(user, '@');
		if (cp != NOSTR) {
			if (!inubuf) {
				strncpy(ubuf, user, cp - user);
				ubuf[cp - user] = '\0';
				user = ubuf;
			} else
				*cp = '\0';
		}
	}
	return (user);
}

/*
 * Implement allnet options.
 */
int
samebody(register char *user, register char *addr, int fuzzy)
{
	char ubuf[BUFSIZ], abuf[BUFSIZ];
	char *allnet = value("allnet");
	int nbangs = allnet ? (strcmp(allnet, "uucp") == 0) ? 2 : 1 : 0;

	if (fuzzy && value("fuzzymatch")) {
		int i;

		(void) strlcpy(ubuf, user, BUFSIZ);
		for (i = 0; ubuf[i]; i++)
			ubuf[i] = tolower(ubuf[i]);
		(void) strlcpy(abuf, addr, BUFSIZ);
		for (i = 0; abuf[i]; i++)
			abuf[i] = tolower(abuf[i]);
		return (strstr(abuf, ubuf) != NOSTR);
	}
	user = norm(user, ubuf, nbangs);
	addr = norm(addr, abuf, nbangs);
	return (strcmp(user, addr) == 0);
}

/*
 * Compute the length of the passed name list and
 * return it.
 */
static int
lengthof(struct name *name)
{
	register struct name *np;
	register int c;

	for (c = 0, np = name; np != NIL; c++, np = np->n_flink)
		;
	return (c);
}

/*
 * Concatenate the two passed name lists, return the result.
 */

struct name *
cat(struct name *n1, struct name *n2)
{
	register struct name *tail;

	if (n1 == NIL)
		return (n2);
	if (n2 == NIL)
		return (n1);
	tail = tailof(n1);
	tail->n_flink = n2;
	n2->n_blink = tail;
	return (n1);
}

/*
 * Unpack the name list onto a vector of strings.
 * Return an error if the name list won't fit.
 */

char **
unpack(struct name *np)
{
	register char **ap, **top;
	register struct name *n;
	char hbuf[10];
	int t, extra, metoo, verbose;

	n = np;
	if ((t = lengthof(n)) == 0)
		panic("No names to unpack");

	/*
	 * Compute the number of extra arguments we will need.  We need at least
	 * 3 extra -- one for "mail", one for a terminating -- to stop sendmail
	 * option processing, and one for the terminating 0 pointer.
	 *
	 * Additional spots may be needed to pass along -r and -f to the host
	 * mailer.
	 */

	extra = 3;

	if (rflag != NOSTR)
		extra += 2;
	extra++;
	metoo = value("metoo") != NOSTR;
	if (metoo)
		extra++;
	verbose = value("verbose") != NOSTR;
	if (verbose)
		extra++;
	if (hflag)
		extra += 2;
	top = (char **)salloc((t + extra) * sizeof (char *));
	ap = top;
	*ap++ = "sendmail";
	if (rflag != NOSTR) {
		*ap++ = "-r";
		*ap++ = rflag;
	}
	*ap++ = "-i";
	if (metoo)
		*ap++ = "-m";
	if (verbose)
		*ap++ = "-v";
	if (hflag) {
		*ap++ = "-h";
		snprintf(hbuf, sizeof (hbuf), "%d", hflag);
		*ap++ = savestr(hbuf);
	}
	*ap++ = "--";
	while (n != NIL) {
		if (n->n_type & GDEL) {
			n = n->n_flink;
			continue;
		}
		*ap++ = n->n_name;
		n = n->n_flink;
	}
	*ap = NOSTR;
	return (top);
}

/*
 * See if the user named themself as a destination
 * for outgoing mail. If so, set the global flag
 * selfsent so that we avoid removing their mailbox.
 */

void
mechk(struct name *names)
{
	register struct name *np;

	for (np = names; np != NIL; np = np->n_flink)
		if ((np->n_type & GDEL) == 0 &&
		    samebody(np->n_name, myname, FALSE)) {
			selfsent++;
			return;
		}
}

/*
 * Remove all of the duplicates from the passed name list by
 * insertion sorting them, then checking for dups.
 * Return the head of the new list.
 */

struct name *
elide(struct name *names)
{
	register struct name *np, *t, *newnames;
	struct name *x;

	if (names == NIL)
		return (NIL);
	newnames = names;
	np = names;
	np = np->n_flink;
	if (np != NIL)
		np->n_blink = NIL;
	newnames->n_flink = NIL;
	while (np != NIL) {
		t = newnames;
		while (strcmp(t->n_name, np->n_name) < 0) {
			if (t->n_flink == NIL)
				break;
			t = t->n_flink;
		}

		/*
		 * If we ran out of t's, put the new entry after
		 * the current value of t.
		 */

		if (strcmp(t->n_name, np->n_name) < 0) {
			t->n_flink = np;
			np->n_blink = t;
			t = np;
			np = np->n_flink;
			t->n_flink = NIL;
			continue;
		}

		/*
		 * Otherwise, put the new entry in front of the
		 * current t.  If at the front of the list,
		 * the new guy becomes the new head of the list.
		 */

		if (t == newnames) {
			t = np;
			np = np->n_flink;
			t->n_flink = newnames;
			newnames->n_blink = t;
			t->n_blink = NIL;
			newnames = t;
			continue;
		}

		/*
		 * The normal case -- we are inserting into the
		 * middle of the list.
		 */

		x = np;
		np = np->n_flink;
		x->n_flink = t;
		x->n_blink = t->n_blink;
		t->n_blink->n_flink = x;
		t->n_blink = x;
	}

	/*
	 * Now the list headed up by new is sorted.
	 * Go through it and remove duplicates.
	 * Remember the best "type" among all the
	 * duplicates of a name.
	 */

	np = newnames;
	while (np != NIL) {
		int type;

		t = np;
		type = np->n_type;
		while (t->n_flink != NIL &&
		    strcmp(np->n_name, t->n_flink->n_name) == 0) {
			t = t->n_flink;
			/* "To" before "Cc" before "Bcc" */
			if (t->n_type < type)
				type = t->n_type;
		}
		if (t == np || t == NIL) {
			np = np->n_flink;
			continue;
		}

		/*
		 * Now t points to the last entry with the same name
		 * as np.  Make np point beyond t.
		 */

		np->n_flink = t->n_flink;
		if (t->n_flink != NIL)
			t->n_flink->n_blink = np;
		np->n_type = type;
		np = np->n_flink;
	}
	return (newnames);
}

/*
 * Put another node onto a list of names and return
 * the list.
 */

static struct name *
put(struct name *list, struct name *node)
{
	node->n_flink = list;
	node->n_blink = NIL;
	if (list != NIL)
		list->n_blink = node;
	return (node);
}


/*
 * Delete the given name from a namelist.
 */
struct name *
delname(register struct name *np, char name[])
{
	register struct name *p;

	for (p = np; p != NIL; p = p->n_flink)
		if (samebody(name, p->n_name, FALSE)) {
			if (p->n_blink == NIL) {
				if (p->n_flink != NIL)
					p->n_flink->n_blink = NIL;
				np = p->n_flink;
				continue;
			}
			if (p->n_flink == NIL) {
				if (p->n_blink != NIL)
					p->n_blink->n_flink = NIL;
				continue;
			}
			p->n_blink->n_flink = p->n_flink;
			p->n_flink->n_blink = p->n_blink;
		}
	return (np);
}

/*
 * Call the given routine on each element of the name
 * list, replacing said value if need be.
 */

void
mapf(register struct name *np, char *from)
{
	register struct name *p;

	if (debug) fprintf(stderr, "mapf %lx, %s\n", (long)np, from);
	for (p = np; p != NIL; p = p->n_flink)
		if ((p->n_type & GDEL) == 0) {
			p->n_name = netmap(p->n_name, from);
			p->n_full = splice(p->n_name, p->n_full);
		}
	if (debug) fprintf(stderr, "mapf %s done\n", from);
}