commit 14ae3944ec7b3c26fedacdad6a3bea52cd1eb69e
from: Omar Polo <op@omarpolo.com>
date: Wed Nov 23 14:14:28 2022 UTC

kamiftp: automatic cd or fetch on the given path

before the given path was used for Tattach.  Turns out at least u9fs
doesn't seem to use that field for the initial directory (not sure if it
should).  kamiftp now always issues a Tattach with aname="/" and then
does a Twalk on the path: if it names a directory, it becomes the remote
working directory like a `cd' was issued, if it names a file it is
fetched and kamiftp quits.

commit - 2c50e0f6595eb735d3345687359274f63b9d7fbb
commit + 14ae3944ec7b3c26fedacdad6a3bea52cd1eb69e
blob - e4b96ddb060ed95f23c81c4b0d247ba918591243
blob + bbf38dbad9efedadce54a233c29207ce0bbf6ccd
--- kamiftp/ftp.c
+++ kamiftp/ftp.c
@@ -58,10 +58,6 @@
 int		 tls;
 const char	*crtpath;
 const char	*keypath;
-
-char		*user;
-char		*host;
-char		*port;
 
 /* state */
 FILE			*fp;
@@ -462,7 +458,7 @@ do_version(void)
 }
 
 static void
-do_attach()
+do_attach(const char *user)
 {
 	struct qid qid;
 
@@ -911,39 +907,11 @@ dial(const char *host, const char *port)
 }
 
 static void
-do_connect(const char *connspec, const char *path)
+do_connect(const char *host, const char *port, const char *user)
 {
-	char pathbuf[PATH_MAX];
-	char *t;
-	const char *port;
-
-	host = xstrdup(connspec);
-
-	if ((t = strchr(host, '/')) != NULL) {
-		if (t == host)
-			errx(1, "invalid connection string: %s", connspec);
-		if (strlcpy(pathbuf, t, sizeof(pathbuf)) >= sizeof(pathbuf))
-			errx(1, "path too long: %s", t);
-		path = pathbuf;
-		*t = '\0';
-	}
-
-	if ((t = strchr(host, '@')) != NULL) {
-		if (t == host)
-			errx(1, "invalid connection string: %s", connspec);
-		*t = '\0';
-		user = host;
-		host = ++t;
-	} else if ((user = getenv("USER")) == NULL)
-		errx(1, "USER not defined");
-
-	if ((t = strchr(host, ':')) != NULL) {
-		*t = '\0';
-		port = ++t;
-		if (*port == '\0')
-			errx(1, "invalid connection string: %s", connspec);
-	} else
-		port = "1337";
+	struct qid qid;
+	int nfid, miss, fd;
+	char *errstr;
 
 	printf("connecting to %s:%s...", host, port);
 	fflush(stdout);
@@ -993,7 +961,7 @@ do_connect(const char *connspec, const char *path)
 	printf(" done!\n");
 
 	do_version();
-	do_attach();
+	do_attach(user);
 }
 
 static int
@@ -1616,12 +1584,96 @@ excmd(int argc, const char **argv)
 	}
 
 	log_warnx("unknown command %s", *argv);
+}
+
+static void
+cd_or_fetch(const char *path)
+{
+	struct qid	 qid;
+	const char	*l;
+	char		*errstr;
+	int		 fd, nfid, miss;
+
+	while (*path == '/')
+		path++;
+	if (*path == '\0')
+		return;
+
+	nfid = nextfid();
+	errstr = walk_path(pwdfid, nfid, path, &miss, &qid);
+	if (errstr)
+		errx(1, "walk %s: %s", path, errstr);
+	if (miss)
+		errc(1, ENOENT, "walk %s", path);
+
+	if (qid.type & QTDIR) {
+		do_clunk(pwdfid);
+		pwdfid = nfid;
+		return;
+	}
+
+	if ((l = strrchr(path, '/')) == NULL)
+		l = path;
+	else
+		l++;
+	if (*l == '\0')
+		errx(1, "invalid path: missing file name: %s", path);
+
+	if ((fd = open(l, O_WRONLY|O_CREAT, 0644)) == -1)
+		err(1, "can't open for writing %s", l);
+	if (fetch_fid(nfid, fd, l) == -1)
+		err(1, "write %s", l);
+	close(fd);
+	fclose(fp);
+	exit(0);
 }
 
+static const char *
+parse_addr(const char *url, const char **user,
+    const char **port, const char **path)
+{
+	static char	 buf[PATH_MAX];
+	char		*host, *t;
+
+	*user = *port = *path = NULL;
+	host = buf;
+
+	if (strlcpy(buf, url, sizeof(buf)) >= sizeof(buf))
+		errx(1, "connection string too long");
+
+	if ((t = strchr(host, '/')) != NULL) {
+		if (t == host)
+			errx(1, "invalid connection string: %s", url);
+		*t++ = '\0';
+		if (*t != '\0')
+			*path = t;
+	}
+
+	if ((t = strchr(host, '@')) != NULL) {
+		if (t == host)
+			errx(1, "invalid connection string: %s", url);
+		*t++ = '\0';
+		*user = host;
+		host = t;
+	} else if ((*user = getenv("USER")) == NULL)
+		errx(1, "USER not defined");
+
+	if ((t = strchr(host, ':')) != NULL) {
+		*t++ = '\0';
+		if (*t != '\0')
+			*port = t;
+	}
+	if (*port == NULL)
+		*port = "1337";
+
+	return host;
+}
+
 int
 main(int argc, char **argv)
 {
-	int	ch;
+	const char	*user, *host, *port, *path;
+	int		 ch;
 
 	log_init(1, LOG_DAEMON);
 	log_setverbose(0);
@@ -1650,6 +1702,10 @@ main(int argc, char **argv)
 	if (argc == 0 || (tls && crtpath == NULL))
 		usage(1);
 
+	host = parse_addr(argv[0], &user, &port, &path);
+	if (path == NULL && argv[1] != NULL)
+		path = argv[1];
+
 	signal(SIGPIPE, SIG_IGN);
 	if (isatty(1)) {
 		tty_p = 1;
@@ -1666,7 +1722,9 @@ main(int argc, char **argv)
 	if ((dirbuf = evbuffer_new()) == NULL)
 		fatal("evbuferr_new");
 
-	do_connect(argv[0], argv[1]);
+	do_connect(host, port, user);
+	if (path)
+		cd_or_fetch(path);
 
 	for (;;) {
 		int argc = 0;
blob - 6c0dd553a4d6a5635b14d94f7ed23becf8912790
blob + 9c533666fa46400322e16af1b66d1e193415af96
--- kamiftp/kamiftp.1
+++ kamiftp/kamiftp.1
@@ -29,6 +29,12 @@
 is a
 .Xr 9p 7
 client.
+If
+.Ar path
+names a remote file,
+.Nm
+downloads it in the current directory and exit, otherwise changes the
+remote working directory and starts accepting commands.
 .Pp
 The options are as follows:
 .Bl -tag -width Ds