sacc

sacc.c (18263B)

---

 /* See LICENSE file for copyright and license details. */
 #include <ctype.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <limits.h>
 #include <locale.h>
 #include <netdb.h>
 #include <netinet/in.h>
 #include <signal.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 #include <wchar.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 
 #include "common.h"
 #include "tls.h"
 
 #include "config.h"
 
 static char *mainurl;
 static Item *mainentry;
 static int devnullfd;
 static int parent = 1;
 static int interactive;
 static int dotls = 0;
 static struct tls *tlsctx = NULL;
 
 static void (*diag)(char *fmt, ...);
 
 void
 stddiag(char *fmt, ...)
 {
 	va_list arg;
 
 	va_start(arg, fmt);
 	vfprintf(stderr, fmt, arg);
 	va_end(arg);
 	fputc('\n', stderr);
 }
 
 void
 die(const char *fmt, ...)
 {
 	va_list arg;
 
 	va_start(arg, fmt);
 	vfprintf(stderr, fmt, arg);
 	va_end(arg);
 	fputc('\n', stderr);
 
 	exit(1);
 }
 
 static ssize_t
 read_wrap(int s, void *buf, size_t bs)
 {
 	if (tlsctx) {
 		ssize_t r = TLS_WANT_POLLIN;
 		while (r == TLS_WANT_POLLIN || r == TLS_WANT_POLLOUT)
 			r = tls_read(tlsctx, buf, bs);
 		return r;
 	}
 	return read(s, buf, bs);
 }
 
 static ssize_t
 write_wrap(int fd, const void *buf, size_t nbyte)
 {
 	if (tlsctx) {
 		ssize_t r = TLS_WANT_POLLIN;
 		while (r == TLS_WANT_POLLIN || r == TLS_WANT_POLLOUT)
 			r = tls_write(tlsctx, buf, nbyte);
 		return r;
 	}
 	return write(fd, buf, nbyte);
 }
 
 static int
 close_wrap(int fd)
 {
 	if (tlsctx) {
 		tls_close(tlsctx);
 		tls_reset(tlsctx);
 	}
 	return close(fd);
 }
 
 #ifdef NEED_ASPRINTF
 int
 asprintf(char **s, const char *fmt, ...)
 {
 	va_list ap;
 	int n;
 
 	va_start(ap, fmt);
 	n = vsnprintf(NULL, 0, fmt, ap);
 	va_end(ap);
 
 	if (n == INT_MAX || !(*s = malloc(++n)))
 		return -1;
 
 	va_start(ap, fmt);
 	vsnprintf(*s, n, fmt, ap);
 	va_end(ap);
 
 	return n;
 }
 #endif /* NEED_ASPRINTF */
 
 #ifdef NEED_STRCASESTR
 char *
 strcasestr(const char *h, const char *n)
 {
 	size_t i;
 
 	if (!n[0])
 		return (char *)h;
 
 	for (; *h; ++h) {
 		for (i = 0; n[i] && tolower((unsigned char)n[i]) ==
 		            tolower((unsigned char)h[i]); ++i)
 			;
 		if (n[i] == '\0')
 			return (char *)h;
 	}
 
 	return NULL;
 }
 #endif /* NEED_STRCASESTR */
 
 /* print `len' columns of characters. */
 size_t
 mbsprint(const char *s, size_t len)
 {
 	wchar_t wc;
 	size_t col = 0, i, slen;
 	const char *p;
 	int rl, pl, w;
 
 	if (!len)
 		return col;
 
 	slen = strlen(s);
 	for (i = 0; i < slen; i += rl) {
 		rl = mbtowc(&wc, s + i, slen - i < 4 ? slen - i : 4);
 		if (rl == -1) {
 			/* reset state */
 			mbtowc(NULL, NULL, 0);
 			p = "\xef\xbf\xbd"; /* replacement character */
 			pl = 3;
 			rl = w = 1;
 		} else {
 			if ((w = wcwidth(wc)) == -1)
 				continue;
 			pl = rl;
 			p = s + i;
 		}
 		if (col + w > len || (col + w == len && s[i + rl])) {
 			fputs("\xe2\x80\xa6", stdout); /* ellipsis */
 			col++;
 			break;
 		}
 		fwrite(p, 1, pl, stdout);
 		col += w;
 	}
 	return col;
 }
 
 static void *
 xreallocarray(void *m, size_t n, size_t s)
 {
 	void *nm;
 
 	if (n == 0 || s == 0) {
 		free(m);
 		return NULL;
 	}
 	if (s && n > (size_t)-1/s)
 		die("realloc: overflow");
 	if (!(nm = realloc(m, n * s)))
 		die("realloc: %s", strerror(errno));
 
 	return nm;
 }
 
 static void *
 xmalloc(const size_t n)
 {
 	void *m = malloc(n);
 
 	if (!m)
 		die("malloc: %s", strerror(errno));
 
 	return m;
 }
 
 static void *
 xcalloc(size_t n)
 {
 	char *m = calloc(1, n);
 
 	if (!m)
 		die("calloc: %s", strerror(errno));
 
 	return m;
 }
 
 static char *
 xstrdup(const char *str)
 {
 	char *s;
 
 	if (!(s = strdup(str)))
 		die("strdup: %s", strerror(errno));
 
 	return s;
 }
 
 static void
 usage(void)
 {
 	die("usage: sacc URL");
 }
 
 static void
 clearitem(Item *item)
 {
 	Dir *dir;
 	Item *items;
 	char *tag;
 	size_t i;
 
 	if (!item)
 		return;
 
 	if (dir = item->dat) {
 		items = dir->items;
 		for (i = 0; i < dir->nitems; ++i)
 			clearitem(&items[i]);
 		free(items);
 		clear(&item->dat);
 	}
 
 	if (parent && (tag = item->tag) &&
 	    !strncmp(tag, tmpdir, strlen(tmpdir)))
 		unlink(tag);
 
 	clear(&item->tag);
 	clear(&item->raw);
 }
 
 const char *
 typedisplay(char t)
 {
 	switch (t) {
 	case '0':
 		return "Text+";
 	case '1':
 		return "Dir +";
 	case '2':
 		return "CSO |";
 	case '3':
 		return "Err |";
 	case '4':
 		return "Macf+";
 	case '5':
 		return "DOSf+";
 	case '6':
 		return "UUEf+";
 	case '7':
 		return "Find+";
 	case '8':
 		return "Tlnt+";
 	case '9':
 		return "Binf+";
 	case '+':
 		return "Mirr+";
 	case 'T':
 		return "IBMt|";
 	case 'g':
 		return "GIF +";
 	case 'I':
 		return "Img +";
 	case 'h':
 		return "HTML+";
 	case 'i':
 		return "    |";
 	default:
 		/* "Characters '0' through 'Z' are reserved." (ASCII) */
 		if (t >= '0' && t <= 'Z')
 			return "!   |";
 		else
 			return "UNKN|";
 	}
 }
 
 static void
 printdir(Item *item)
 {
 	Dir *dir;
 	Item *items;
 	size_t i, nitems;
 
 	if (!item || !(dir = item->dat))
 		return;
 
 	items = dir->items;
 	nitems = dir->nitems;
 
 	for (i = 0; i < nitems; ++i) {
 		printf("%s%s\n",
 		       typedisplay(items[i].type), items[i].username);
 	}
 }
 
 static void
 displaytextitem(Item *item)
 {
 	FILE *pagerin;
 	int pid, wpid;
 
 	uicleanup();
 	switch (pid = fork()) {
 	case -1:
 		diag("Couldn't fork.");
 		return;
 	case 0:
 		parent = 0;
 		if (!(pagerin = popen("$PAGER", "w")))
 			_exit(1);
 		fputs(item->raw, pagerin);
 		exit(pclose(pagerin));
 	default:
 		while ((wpid = wait(NULL)) >= 0 && wpid != pid)
 			;
 	}
 	uisetup();
 }
 
 static char *
 pickfield(char **raw, const char *sep)
 {
 	char c, *r, *f = *raw;
 
 	for (r = *raw; (c = *r) && !strchr(sep, c); ++r) {
 		if (c == '\n')
 			goto skipsep;
 	}
 
 	*r++ = '\0';
 skipsep:
 	*raw = r;
 
 	return f;
 }
 
 static char *
 invaliditem(char *raw)
 {
 	char c;
 	int tabs;
 
 	for (tabs = 0; (c = *raw) && c != '\n'; ++raw) {
 		if (c == '\t')
 			++tabs;
 	}
 	if (tabs < 3) {
 		*raw++ = '\0';
 		return raw;
 	}
 
 	return NULL;
 }
 
 static void
 molditem(Item *item, char **raw)
 {
 	char *next;
 
 	if (!*raw)
 		return;
 
 	if ((next = invaliditem(*raw))) {
 		item->username = *raw;
 		*raw = next;
 		return;
 	}
 
 	item->type = *raw[0]++;
 	item->username = pickfield(raw, "\t");
 	item->selector = pickfield(raw, "\t");
 	item->host = pickfield(raw, "\t");
 	item->port = pickfield(raw, "\t\r");
 	while (*raw[0] != '\n')
 		++*raw;
 	*raw[0]++ = '\0';
 }
 
 static Dir *
 molddiritem(char *raw)
 {
 	Item *item, *items = NULL;
 	char *s, *nl, *p;
 	Dir *dir;
 	size_t i, n, nitems;
 
 	for (s = nl = raw, nitems = 0; p = strchr(nl, '\n'); ++nitems) {
 		s = nl;
 		nl = p+1;
 	}
 	if (!nitems) {
 		diag("Couldn't parse dir item");
 		return NULL;
 	}
 
 	dir = xmalloc(sizeof(Dir));
 	items = xreallocarray(items, nitems, sizeof(Item));
 	memset(items, 0, nitems * sizeof(Item));
 
 	for (i = 0; i < nitems; ++i) {
 		item = &items[i];
 		molditem(item, &raw);
 		if (item->type == '+') {
 			for (n = i - 1; n < (size_t)-1; --n) {
 				if (items[n].type != '+') {
 					item->redtype = items[n].type;
 					break;
 				}
 			}
 		}
 	}
 
 	dir->items = items;
 	dir->nitems = nitems;
 	dir->printoff = dir->curline = 0;
 
 	return dir;
 }
 
 static char *
 getrawitem(int sock)
 {
 	char *raw, *buf;
 	size_t bn, bs;
 	ssize_t n;
 
 	raw = buf = NULL;
 	bn = bs = n = 0;
 
 	do {
 		bs -= n;
 		buf += n;
 
 		if (buf - raw >= 5) {
 			if (strncmp(buf-5, "\r\n.\r\n", 5) == 0) {
 				buf[-3] = '\0';
 				break;
 			}
 		} else if (buf - raw == 3 && strncmp(buf-3, ".\r\n", 3)) {
 			buf[-3] = '\0';
 			break;
 		}
 
 		if (bs < 1) {
 			raw = xreallocarray(raw, ++bn, BUFSIZ);
 			buf = raw + (bn-1) * BUFSIZ;
 			bs = BUFSIZ;
 		}
 	} while ((n = read_wrap(sock, buf, bs)) > 0);
 
 	*buf = '\0';
 
 	if (n < 0) {
 		diag("Can't read socket: %s",
 		     tlsctx ? tls_error(tlsctx) : strerror(errno));
 		clear(&raw);
 	}
 
 	return raw;
 }
 
 
 static int
 sendselector(int sock, const char *selector)
 {
 	char *msg, *p;
 	size_t ln;
 	ssize_t n;
 
 	ln = strlen(selector) + 3;
 	msg = p = xmalloc(ln);
 	snprintf(msg, ln--, "%s\r\n", selector);
 
 	while ((n = write_wrap(sock, p, ln)) > 0) {
 		ln -= n;
 		p += n;
 	}
 
 	free(msg);
 	if (n == -1)
 		diag("Can't send message: %s",
 		     tlsctx ? tls_error(tlsctx) : strerror(errno));
 
 	return n;
 }
 
 static int
 connectto(const char *host, const char *port)
 {
 	sigset_t set, oset;
 	static const struct addrinfo hints = {
 	    .ai_family = AF_UNSPEC,
 	    .ai_socktype = SOCK_STREAM,
 	    .ai_protocol = IPPROTO_TCP,
 	};
 	struct addrinfo *addrs, *addr;
 	int r, t = 0, sock = -1;
 
 	sigemptyset(&set);
 	sigaddset(&set, SIGWINCH);
 	sigprocmask(SIG_BLOCK, &set, &oset);
 
 	if (r = getaddrinfo(host, port, &hints, &addrs)) {
 		diag("Can't resolve hostname \"%s\": %s",
 		     host, gai_strerror(r));
 		goto err;
 	}
 
 	for (addr = addrs; addr; addr = addr->ai_next) {
 		if ((sock = socket(addr->ai_family, addr->ai_socktype,
 		                   addr->ai_protocol)) < 0)
 			continue;
 		if ((r = connect(sock, addr->ai_addr, addr->ai_addrlen)) < 0) {
 			close_wrap(sock);
 			continue;
 		}
 		if (dotls) {
 			tlsctx = tls_client();
 			t = tls_connect_socket(tlsctx, sock, host);
 		}
 		break;
 	}
 
 	freeaddrinfo(addrs);
 
 	if (sock < 0) {
 		diag("Can't open socket: %s", strerror(errno));
 		goto err;
 	}
 	if (r < 0) {
 		diag("Can't connect to: %s:%s: %s",
 		     host, port, strerror(errno));
 		goto err;
 	}
 	if (t < 0) {
 		diag("Can't init TLS : %s", tls_error(tlsctx));
 		goto err;
 	}
 
 	sigprocmask(SIG_SETMASK, &oset, NULL);
 	return sock;
 
 err:
 	sigprocmask(SIG_SETMASK, &oset, NULL);
 	return -1;
 }
 
 static int
 download(Item *item, int dest)
 {
 	char buf[BUFSIZ];
 	ssize_t r, w;
 	int src;
 
 	if (!item->tag) {
 		if ((src = connectto(item->host, item->port)) < 0 ||
 		    sendselector(src, item->selector) < 0)
 			return 0;
 	} else if ((src = open(item->tag, O_RDONLY)) < 0) {
 		printf("Can't open source file %s: %s",
 		       item->tag, strerror(errno));
 		errno = 0;
 		return 0;
 	}
 
 	w = 0;
 	while ((r = read_wrap(src, buf, BUFSIZ)) > 0) {
 		while ((w = write(dest, buf, r)) > 0)
 			r -= w;
 	}
 
 	if (r < 0 || w < 0) {
 		printf("Error downloading file %s: %s",
 		       item->selector, strerror(errno));
 		errno = 0;
 	}
 
 	close_wrap(src);
 
 	return (r == 0 && w == 0);
 }
 
 static void
 downloaditem(Item *item)
 {
 	char *file, *path, *tag;
 	mode_t mode = S_IRUSR|S_IWUSR|S_IRGRP;
 	int dest;
 
 	if (file = strrchr(item->selector, '/'))
 		++file;
 	else
 		file = item->selector;
 
 	if (!(path = uiprompt("Download to [%s] (^D cancel): ", file)))
 		return;
 
 	if (!path[0])
 		path = xstrdup(file);
 
 	if (tag = item->tag) {
 		if (access(tag, R_OK) < 0) {
 			clear(&item->tag);
 		} else if (!strcmp(tag, path)) {
 			goto cleanup;
 		}
 	}
 
 	if ((dest = open(path, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0) {
 		diag("Can't open destination file %s: %s",
 		     path, strerror(errno));
 		errno = 0;
 		goto cleanup;
 	}
 
 	if (!download(item, dest))
 		goto cleanup;
 
 	if (item->tag)
 		goto cleanup;
 
 	item->tag = path;
 
 	return;
 cleanup:
 	free(path);
 	return;
 }
 
 static int
 fetchitem(Item *item)
 {
 	char *raw, *r;
 	int sock;
 
 	if ((sock = connectto(item->host, item->port)) < 0 ||
 	    sendselector(sock, item->selector) < 0)
 		return 0;
 	raw = getrawitem(sock);
 	close_wrap(sock);
 
 	if (raw == NULL || !*raw) {
 		diag("Empty response from server");
 		clear(&raw);
 	}
 
 	return ((item->raw = raw) != NULL);
 }
 
 static void
 plumb(char *url)
 {
 	switch (fork()) {
 	case -1:
 		diag("Couldn't fork.");
 		return;
 	case 0:
 		parent = 0;
 		dup2(devnullfd, 1);
 		dup2(devnullfd, 2);
 		if (execlp(plumber, plumber, url, NULL) < 0)
 			_exit(1);
 	}
 
 	diag("Plumbed \"%s\"", url);
 }
 
 static void
 plumbitem(Item *item)
 {
 	char *file, *path, *tag;
 	mode_t mode = S_IRUSR|S_IWUSR|S_IRGRP;
 	int dest, plumbitem;
 
 	if (file = strrchr(item->selector, '/'))
 		++file;
 	else
 		file = item->selector;
 
 	path = uiprompt("Download %s to (^D cancel, <empty> plumb): ",
 	                file);
 	if (!path)
 		return;
 
 	if ((tag = item->tag) && access(tag, R_OK) < 0) {
 		clear(&item->tag);
 		tag = NULL;
 	}
 
 	plumbitem = path[0] ? 0 : 1;
 
 	if (!path[0]) {
 		clear(&path);
 		if (!tag) {
 			if (asprintf(&path, "%s/%s", tmpdir, file) < 0)
 				die("Can't generate tmpdir path: %s/%s: %s",
 				    tmpdir, file, strerror(errno));
 		}
 	}
 
 	if (path && (!tag || strcmp(tag, path))) {
 		if ((dest = open(path, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0) {
 			diag("Can't open destination file %s: %s",
 			     path, strerror(errno));
 			errno = 0;
 			goto cleanup;
 		}
 		if (!download(item, dest) || tag)
 			goto cleanup;
 	}
 
 	if (!tag)
 		item->tag = path;
 
 	if (plumbitem)
 		plumb(item->tag);
 
 	return;
 cleanup:
 	free(path);
 	return;
 }
 
 static int
 dig(Item *entry, Item *item)
 {
 	char *plumburi = NULL;
 	int t;
 
 	if (item->raw) /* already in cache */
 		return item->type;
 	if (!item->entry)
 		item->entry = entry ? entry : item;
 
 	t = item->redtype ? item->redtype : item->type;
 	switch (t) {
 	case 'h': /* fallthrough */
 		if (!strncmp(item->selector, "URL:", 4)) {
 			plumb(item->selector+4);
 			return 0;
 		}
 	case '0':
 		if (!fetchitem(item))
 			return 0;
 		break;
 	case '1':
 	case '7':
 		if (!fetchitem(item) || !(item->dat = molddiritem(item->raw)))
 			return 0;
 		break;
 	case '4':
 	case '5':
 	case '6':
 	case '9':
 		downloaditem(item);
 		return 0;
 	case '8':
 		if (asprintf(&plumburi, "telnet://%s%s%s:%s",
 		             item->selector, item->selector ? "@" : "",
 		             item->host, item->port) < 0)
 			return 0;
 		plumb(plumburi);
 		free(plumburi);
 		return 0;
 	case 'T':
 		if (asprintf(&plumburi, "tn3270://%s%s%s:%s",
 		             item->selector, item->selector ? "@" : "",
 		             item->host, item->port) < 0)
 			return 0;
 		plumb(plumburi);
 		free(plumburi);
 		return 0;
 	default:
 		if (t >= '0' && t <= 'Z') {
 			diag("Type %c (%s) not supported", t, typedisplay(t));
 			return 0;
 		}
 	case 'g':
 	case 'I':
 		plumbitem(item);
 	case 'i':
 		return 0;
 	}
 
 	return item->type;
 }
 
 static char *
 searchselector(Item *item)
 {
 	char *pexp, *exp, *tag, *selector = item->selector;
 	size_t n = strlen(selector);
 
 	if ((tag = item->tag) && !strncmp(tag, selector, n))
 		pexp = tag + n+1;
 	else
 		pexp = "";
 
 	if (!(exp = uiprompt("Enter search string (^D cancel) [%s]: ", pexp)))
 		return NULL;
 
 	if (exp[0] && strcmp(exp, pexp)) {
 		n += strlen(exp) + 2;
 		tag = xmalloc(n);
 		snprintf(tag, n, "%s\t%s", selector, exp);
 	}
 
 	free(exp);
 	return tag;
 }
 
 static int
 searchitem(Item *entry, Item *item)
 {
 	char *sel, *selector;
 
 	if (!(sel = searchselector(item)))
 		return 0;
 
 	if (sel != item->tag)
 		clearitem(item);
 	if (!item->dat) {
 		selector = item->selector;
 		item->selector = item->tag = sel;
 		dig(entry, item);
 		item->selector = selector;
 	}
 	return (item->dat != NULL);
 }
 
 static void
 printout(Item *hole)
 {
 	char t = 0;
 
 	if (!hole)
 		return;
 
 	switch (hole->redtype ? hole->redtype : (t = hole->type)) {
 	case '0':
 		if (dig(hole, hole))
 			fputs(hole->raw, stdout);
 		return;
 	case '1':
 	case '7':
 		if (dig(hole, hole))
 			printdir(hole);
 		return;
 	default:
 		if (t >= '0' && t <= 'Z') {
 			diag("Type %c (%s) not supported", t, typedisplay(t));
 			return;
 		}
 	case '4':
 	case '5':
 	case '6':
 	case '9':
 	case 'g':
 	case 'I':
 		download(hole, 1);
 	case '2':
 	case '3':
 	case '8':
 	case 'T':
 		return;
 	}
 }
 
 static void
 delve(Item *hole)
 {
 	Item *entry = NULL;
 
 	while (hole) {
 		switch (hole->redtype ? hole->redtype : hole->type) {
 		case 'h':
 		case '0':
 			if (dig(entry, hole))
 				displaytextitem(hole);
 			break;
 		case '1':
 		case '+':
 			if (dig(entry, hole) && hole->dat)
 				entry = hole;
 			break;
 		case '7':
 			if (searchitem(entry, hole))
 				entry = hole;
 			break;
 		case 0:
 			diag("Couldn't get %s:%s/%c%s", hole->host,
 			     hole->port, hole->type, hole->selector);
 			break;
 		case '4':
 		case '5':
 		case '6': /* TODO decode? */
 		case '8':
 		case '9':
 		case 'g':
 		case 'I':
 		case 'T':
 		default:
 			dig(entry, hole);
 			break;
 		}
 
 		if (!entry)
 			return;
 
 		do {
 			uidisplay(entry);
 			hole = uiselectitem(entry);
 		} while (hole == entry);
 	}
 }
 
 static Item *
 moldentry(char *url)
 {
 	Item *entry;
 	char *p, *host = url, *port = "70", *gopherpath = "1";
 	int parsed, ipv6;
 
 	if (p = strstr(url, "://")) {
 		if (!strncmp(url, "gopher", p - url))
 			dotls = 0;
 		else if (!strncmp(url, "gophers", p - url))
 			dotls = 1;
 		else
 			die("Protocol not supported: %.*s", p - url, url);
 		host = p + 3;
 	}
 
 	if (*host == '[') {
 		ipv6 = 1;
 		++host;
 	} else {
 		ipv6 = 0;
 	}
 
 	for (parsed = 0, p = host; !parsed && *p; ++p) {
 		switch (*p) {
 		case ']':
 			if (ipv6) {
 				*p = '\0';
 				ipv6 = 0;
 			}
 			continue;
 		case ':':
 			if (!ipv6) {
 				*p = '\0';
 				port = p+1;
 			}
 			continue;
 		case '/':
 			*p = '\0';
 			parsed = 1;
 			continue;
 		}
 	}
 
 	if (*host == '\0' || *port == '\0' || ipv6)
 		die("Can't parse url");
 
 	if (*p != '\0')
 		gopherpath = p;
 
 	entry = xcalloc(sizeof(Item));
 	entry->type = gopherpath[0];
 	entry->username = entry->selector = ++gopherpath;
 	if (entry->type == '7') {
 		if (p = strstr(gopherpath, "%09")) {
 			memmove(p+1, p+3, strlen(p+3)+1);
 			*p = '\t';
 		}
 		if (p || (p = strchr(gopherpath, '\t'))) {
 			asprintf(&entry->tag, "%s", gopherpath);
 			*p = '\0';
 		}
 	}
 	entry->host = host;
 	entry->port = port;
 	entry->entry = entry;
 
 	return entry;
 }
 
 static void
 cleanup(void)
 {
 	clearitem(mainentry);
 	if (parent)
 		rmdir(tmpdir);
 	free(mainentry);
 	free(mainurl);
 	if (interactive)
 		uicleanup();
 }
 
 void
 sighandler(int signo)
 {
 	exit(128 + signo);
 }
 
 static void
 setup(void)
 {
 	struct sigaction sa;
 	int fd;
 
 	setlocale(LC_CTYPE, "");
 	setenv("PAGER", "more", 0);
 	atexit(cleanup);
 	/* reopen stdin in case we're reading from a pipe */
 	if ((fd = open("/dev/tty", O_RDONLY)) < 0)
 		die("open: /dev/tty: %s", strerror(errno));
 	if (dup2(fd, 0) < 0)
 		die("dup2: /dev/tty, stdin: %s", strerror(errno));
 	close(fd);
 	if ((devnullfd = open("/dev/null", O_WRONLY)) < 0)
 		die("open: /dev/null: %s", strerror(errno));
 
 	sigemptyset(&sa.sa_mask);
 	sa.sa_flags = SA_RESTART;
 	sa.sa_handler = sighandler;
 	sigaction(SIGINT, &sa, NULL);
 	sigaction(SIGHUP, &sa, NULL);
 	sigaction(SIGTERM, &sa, NULL);
 
 	if (!mkdtemp(tmpdir))
 		die("mkdir: %s: %s", tmpdir, strerror(errno));
 	if(interactive = isatty(1)) {
 		uisetup();
 		sa.sa_handler = uisigwinch;
 		sigaction(SIGWINCH, &sa, NULL);
 	}
 }
 
 int
 main(int argc, char *argv[])
 {
 	if (argc != 2)
 		usage();
 
 	setup();
 
 	mainurl = xstrdup(argv[1]);
 
 	mainentry = moldentry(mainurl);
 	if (interactive) {
 		diag = uistatus;
 		delve(mainentry);
 	} else {
 		diag = stddiag;
 		printout(mainentry);
 	}
 
 	exit(0);
 }