sftp-int.c

/*
 * Copyright (c) 2001,2002 Damien Miller.  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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/* XXX: recursive operations */

#include "includes.h"
RCSID("$OpenBSD: sftp-int.c,v 1.60 2003/05/15 03:43:59 mouring Exp $");

#include "buffer.h"
#include "xmalloc.h"
#include "log.h"
#include "pathnames.h"

#include "sftp.h"
#include "sftp-common.h"
#include "sftp-glob.h"
#include "sftp-client.h"
#include "sftp-int.h"

/* File to read commands from */
extern FILE *infile;

/* Size of buffer used when copying files */
extern size_t copy_buffer_len;

/* Number of concurrent outstanding requests */
extern int num_requests;

/* This is set to 0 if the progressmeter is not desired. */
int showprogress = 1;

/* Seperators for interactive commands */
#define WHITESPACE " \t\r\n"

/* Define what type of ls view (0 - multi-column) */
#define LONG_VIEW 1		/* Full view ala ls -l */
#define SHORT_VIEW 2		/* Single row view ala ls -1 */

/* Commands for interactive mode */
#define I_CHDIR		1
#define I_CHGRP		2
#define I_CHMOD		3
#define I_CHOWN		4
#define I_GET		5
#define I_HELP		6
#define I_LCHDIR	7
#define I_LLS		8
#define I_LMKDIR	9
#define I_LPWD		10
#define I_LS		11
#define I_LUMASK	12
#define I_MKDIR		13
#define I_PUT		14
#define I_PWD		15
#define I_QUIT		16
#define I_RENAME	17
#define I_RM		18
#define I_RMDIR		19
#define I_SHELL		20
#define I_SYMLINK	21
#define I_VERSION	22
#define I_PROGRESS	23

struct CMD {
	const char *c;
	const int n;
};

static const struct CMD cmds[] = {
	{ "bye",	I_QUIT },
	{ "cd",		I_CHDIR },
	{ "chdir",	I_CHDIR },
	{ "chgrp",	I_CHGRP },
	{ "chmod",	I_CHMOD },
	{ "chown",	I_CHOWN },
	{ "dir",	I_LS },
	{ "exit",	I_QUIT },
	{ "get",	I_GET },
	{ "mget",	I_GET },
	{ "help",	I_HELP },
	{ "lcd",	I_LCHDIR },
	{ "lchdir",	I_LCHDIR },
	{ "lls",	I_LLS },
	{ "lmkdir",	I_LMKDIR },
	{ "ln",		I_SYMLINK },
	{ "lpwd",	I_LPWD },
	{ "ls",		I_LS },
	{ "lumask",	I_LUMASK },
	{ "mkdir",	I_MKDIR },
	{ "progress",	I_PROGRESS },
	{ "put",	I_PUT },
	{ "mput",	I_PUT },
	{ "pwd",	I_PWD },
	{ "quit",	I_QUIT },
	{ "rename",	I_RENAME },
	{ "rm",		I_RM },
	{ "rmdir",	I_RMDIR },
	{ "symlink",	I_SYMLINK },
	{ "version",	I_VERSION },
	{ "!",		I_SHELL },
	{ "?",		I_HELP },
	{ NULL,			-1}
};

static void
help(void)
{
	printf("Available commands:\n");
	printf("cd path                       Change remote directory to 'path'\n");
	printf("lcd path                      Change local directory to 'path'\n");
	printf("chgrp grp path                Change group of file 'path' to 'grp'\n");
	printf("chmod mode path               Change permissions of file 'path' to 'mode'\n");
	printf("chown own path                Change owner of file 'path' to 'own'\n");
	printf("help                          Display this help text\n");
	printf("get remote-path [local-path]  Download file\n");
	printf("lls [ls-options [path]]       Display local directory listing\n");
	printf("ln oldpath newpath            Symlink remote file\n");
	printf("lmkdir path                   Create local directory\n");
	printf("lpwd                          Print local working directory\n");
	printf("ls [path]                     Display remote directory listing\n");
	printf("lumask umask                  Set local umask to 'umask'\n");
	printf("mkdir path                    Create remote directory\n");
	printf("progress                      Toggle display of progress meter\n");
	printf("put local-path [remote-path]  Upload file\n");
	printf("pwd                           Display remote working directory\n");
	printf("exit                          Quit sftp\n");
	printf("quit                          Quit sftp\n");
	printf("rename oldpath newpath        Rename remote file\n");
	printf("rmdir path                    Remove remote directory\n");
	printf("rm path                       Delete remote file\n");
	printf("symlink oldpath newpath       Symlink remote file\n");
	printf("version                       Show SFTP version\n");
	printf("!command                      Execute 'command' in local shell\n");
	printf("!                             Escape to local shell\n");
	printf("?                             Synonym for help\n");
}

static void
local_do_shell(const char *args)
{
	int status;
	char *shell;
	pid_t pid;

	if (!*args)
		args = NULL;

	if ((shell = getenv("SHELL")) == NULL)
		shell = _PATH_BSHELL;

	if ((pid = fork()) == -1)
		fatal("Couldn't fork: %s", strerror(errno));

	if (pid == 0) {
		/* XXX: child has pipe fds to ssh subproc open - issue? */
		if (args) {
			debug3("Executing %s -c \"%s\"", shell, args);
			execl(shell, shell, "-c", args, (char *)NULL);
		} else {
			debug3("Executing %s", shell);
			execl(shell, shell, (char *)NULL);
		}
		fprintf(stderr, "Couldn't execute \"%s\": %s\n", shell,
		    strerror(errno));
		_exit(1);
	}
	while (waitpid(pid, &status, 0) == -1)
		if (errno != EINTR)
			fatal("Couldn't wait for child: %s", strerror(errno));
	if (!WIFEXITED(status))
		error("Shell exited abormally");
	else if (WEXITSTATUS(status))
		error("Shell exited with status %d", WEXITSTATUS(status));
}

static void
local_do_ls(const char *args)
{
	if (!args || !*args)
		local_do_shell(_PATH_LS);
	else {
		int len = strlen(_PATH_LS " ") + strlen(args) + 1;
		char *buf = xmalloc(len);

		/* XXX: quoting - rip quoting code from ftp? */
		snprintf(buf, len, _PATH_LS " %s", args);
		local_do_shell(buf);
		xfree(buf);
	}
}

/* Strip one path (usually the pwd) from the start of another */
static char *
path_strip(char *path, char *strip)
{
	size_t len;

	if (strip == NULL)
		return (xstrdup(path));

	len = strlen(strip);
	if (strip != NULL && strncmp(path, strip, len) == 0) {
		if (strip[len - 1] != '/' && path[len] == '/')
			len++;
		return (xstrdup(path + len));
	}

	return (xstrdup(path));
}

static char *
path_append(char *p1, char *p2)
{
	char *ret;
	int len = strlen(p1) + strlen(p2) + 2;

	ret = xmalloc(len);
	strlcpy(ret, p1, len);
	if (p1[strlen(p1) - 1] != '/')
		strlcat(ret, "/", len);
	strlcat(ret, p2, len);

	return(ret);
}

static char *
make_absolute(char *p, char *pwd)
{
	char *abs;

	/* Derelativise */
	if (p && p[0] != '/') {
		abs = path_append(pwd, p);
		xfree(p);
		return(abs);
	} else
		return(p);
}

static int
infer_path(const char *p, char **ifp)
{
	char *cp;

	cp = strrchr(p, '/');
	if (cp == NULL) {
		*ifp = xstrdup(p);
		return(0);
	}

	if (!cp[1]) {
		error("Invalid path");
		return(-1);
	}

	*ifp = xstrdup(cp + 1);
	return(0);
}

static int
parse_getput_flags(const char **cpp, int *pflag)
{
	const char *cp = *cpp;

	/* Check for flags */
	if (cp[0] == '-' && cp[1] && strchr(WHITESPACE, cp[2])) {
		switch (cp[1]) {
		case 'p':
		case 'P':
			*pflag = 1;
			break;
		default:
			error("Invalid flag -%c", cp[1]);
			return(-1);
		}
		cp += 2;
		*cpp = cp + strspn(cp, WHITESPACE);
	}

	return(0);
}

static int
parse_ls_flags(const char **cpp, int *lflag)
{
	const char *cp = *cpp;

	/* Check for flags */
	if (cp++[0] == '-') {
		for(; strchr(WHITESPACE, *cp) == NULL; cp++) {
			switch (*cp) {
			case 'l':
				*lflag = LONG_VIEW;
				break;
			case '1':
				*lflag = SHORT_VIEW;
				break;
			default:
				error("Invalid flag -%c", *cp);
				return(-1);
			}
		}
		*cpp = cp + strspn(cp, WHITESPACE);
	}

	return(0);
}

static int
get_pathname(const char **cpp, char **path)
{
	const char *cp = *cpp, *end;
	char quot;
	int i;

	cp += strspn(cp, WHITESPACE);
	if (!*cp) {
		*cpp = cp;
		*path = NULL;
		return (0);
	}

	/* Check for quoted filenames */
	if (*cp == '\"' || *cp == '\'') {
		quot = *cp++;

		end = strchr(cp, quot);
		if (end == NULL) {
			error("Unterminated quote");
			goto fail;
		}
		if (cp == end) {
			error("Empty quotes");
			goto fail;
		}
		*cpp = end + 1 + strspn(end + 1, WHITESPACE);
	} else {
		/* Read to end of filename */
		end = strpbrk(cp, WHITESPACE);
		if (end == NULL)
			end = strchr(cp, '\0');
		*cpp = end + strspn(end, WHITESPACE);
	}

	i = end - cp;

	*path = xmalloc(i + 1);
	memcpy(*path, cp, i);
	(*path)[i] = '\0';
	return(0);

 fail:
	*path = NULL;
	return (-1);
}

static int
is_dir(char *path)
{
	struct stat sb;

	/* XXX: report errors? */
	if (stat(path, &sb) == -1)
		return(0);

	return(sb.st_mode & S_IFDIR);
}

static int
is_reg(char *path)
{
	struct stat sb;

	if (stat(path, &sb) == -1)
		fatal("stat %s: %s", path, strerror(errno));

	return(S_ISREG(sb.st_mode));
}

static int
remote_is_dir(struct sftp_conn *conn, char *path)
{
	Attrib *a;

	/* XXX: report errors? */
	if ((a = do_stat(conn, path, 1)) == NULL)
		return(0);
	if (!(a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS))
		return(0);
	return(a->perm & S_IFDIR);
}

static int
process_get(struct sftp_conn *conn, char *src, char *dst, char *pwd, int pflag)
{
	char *abs_src = NULL;
	char *abs_dst = NULL;
	char *tmp;
	glob_t g;
	int err = 0;
	int i;

	abs_src = xstrdup(src);
	abs_src = make_absolute(abs_src, pwd);

	memset(&g, 0, sizeof(g));
	debug3("Looking up %s", abs_src);
	if (remote_glob(conn, abs_src, 0, NULL, &g)) {
		error("File \"%s\" not found.", abs_src);
		err = -1;
		goto out;
	}

	/* If multiple matches, dst must be a directory or unspecified */
	if (g.gl_matchc > 1 && dst && !is_dir(dst)) {
		error("Multiple files match, but \"%s\" is not a directory",
		    dst);
		err = -1;
		goto out;
	}

	for (i = 0; g.gl_pathv[i]; i++) {
		if (infer_path(g.gl_pathv[i], &tmp)) {
			err = -1;
			goto out;
		}

		if (g.gl_matchc == 1 && dst) {
			/* If directory specified, append filename */
			if (is_dir(dst)) {
				if (infer_path(g.gl_pathv[0], &tmp)) {
					err = 1;
					goto out;
				}
				abs_dst = path_append(dst, tmp);
				xfree(tmp);
			} else
				abs_dst = xstrdup(dst);
		} else if (dst) {
			abs_dst = path_append(dst, tmp);
			xfree(tmp);
		} else
			abs_dst = tmp;

		printf("Fetching %s to %s\n", g.gl_pathv[i], abs_dst);
		if (do_download(conn, g.gl_pathv[i], abs_dst, pflag) == -1)
			err = -1;
		xfree(abs_dst);
		abs_dst = NULL;
	}

out:
	xfree(abs_src);
	if (abs_dst)
		xfree(abs_dst);
	globfree(&g);
	return(err);
}

static int
process_put(struct sftp_conn *conn, char *src, char *dst, char *pwd, int pflag)
{
	char *tmp_dst = NULL;
	char *abs_dst = NULL;
	char *tmp;
	glob_t g;
	int err = 0;
	int i;

	if (dst) {
		tmp_dst = xstrdup(dst);
		tmp_dst = make_absolute(tmp_dst, pwd);
	}

	memset(&g, 0, sizeof(g));
	debug3("Looking up %s", src);
	if (glob(src, 0, NULL, &g)) {
		error("File \"%s\" not found.", src);
		err = -1;
		goto out;
	}

	/* If multiple matches, dst may be directory or unspecified */
	if (g.gl_matchc > 1 && tmp_dst && !remote_is_dir(conn, tmp_dst)) {
		error("Multiple files match, but \"%s\" is not a directory",
		    tmp_dst);
		err = -1;
		goto out;
	}

	for (i = 0; g.gl_pathv[i]; i++) {
		if (!is_reg(g.gl_pathv[i])) {
			error("skipping non-regular file %s", 
			    g.gl_pathv[i]);
			continue;
		}
		if (infer_path(g.gl_pathv[i], &tmp)) {
			err = -1;
			goto out;
		}

		if (g.gl_matchc == 1 && tmp_dst) {
			/* If directory specified, append filename */
			if (remote_is_dir(conn, tmp_dst)) {
				if (infer_path(g.gl_pathv[0], &tmp)) {
					err = 1;
					goto out;
				}
				abs_dst = path_append(tmp_dst, tmp);
				xfree(tmp);
			} else
				abs_dst = xstrdup(tmp_dst);

		} else if (tmp_dst) {
			abs_dst = path_append(tmp_dst, tmp);
			xfree(tmp);
		} else
			abs_dst = make_absolute(tmp, pwd);

		printf("Uploading %s to %s\n", g.gl_pathv[i], abs_dst);
		if (do_upload(conn, g.gl_pathv[i], abs_dst, pflag) == -1)
			err = -1;
	}

out:
	if (abs_dst)
		xfree(abs_dst);
	if (tmp_dst)
		xfree(tmp_dst);
	globfree(&g);
	return(err);
}

static int
sdirent_comp(const void *aa, const void *bb)
{
	SFTP_DIRENT *a = *(SFTP_DIRENT **)aa;
	SFTP_DIRENT *b = *(SFTP_DIRENT **)bb;

	return (strcmp(a->filename, b->filename));
}

/* sftp ls.1 replacement for directories */
static int
do_ls_dir(struct sftp_conn *conn, char *path, char *strip_path, int lflag)
{
	int n, c = 1, colspace = 0, columns = 1;
	SFTP_DIRENT **d;

	if ((n = do_readdir(conn, path, &d)) != 0)
		return (n);

	if (!(lflag & SHORT_VIEW)) {
		int m = 0, width = 80;
		struct winsize ws;

		/* Count entries for sort and find longest filename */
		for (n = 0; d[n] != NULL; n++)
			m = MAX(m, strlen(d[n]->filename));

		if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) != -1) 
			width = ws.ws_col;

		columns = width / (m + 2);
		colspace = width / columns;
	}

	qsort(d, n, sizeof(*d), sdirent_comp);

	for (n = 0; d[n] != NULL; n++) {
		char *tmp, *fname;

		tmp = path_append(path, d[n]->filename);
		fname = path_strip(tmp, strip_path);
		xfree(tmp);

		if (lflag & LONG_VIEW) {
			char *lname;
			struct stat sb;

			memset(&sb, 0, sizeof(sb));
			attrib_to_stat(&d[n]->a, &sb);
			lname = ls_file(fname, &sb, 1);
			printf("%s\n", lname);
			xfree(lname);
		} else {
			printf("%-*s", colspace, fname);
			if (c >= columns) {
				printf("\n");
				c = 1;
			} else
				c++;
		}

		xfree(fname);
	}

	if (!(lflag & LONG_VIEW) && (c != 1))
		printf("\n");

	free_sftp_dirents(d);
	return (0);
}

/* sftp ls.1 replacement which handles path globs */
static int
do_globbed_ls(struct sftp_conn *conn, char *path, char *strip_path,
    int lflag)
{
	glob_t g;
	int i, c = 1, colspace = 0, columns = 1;
	Attrib *a;

	memset(&g, 0, sizeof(g));

	if (remote_glob(conn, path, GLOB_MARK|GLOB_NOCHECK|GLOB_BRACE,
	    NULL, &g)) {
		error("Can't ls: \"%s\" not found", path);
		return (-1);
	}

	/*
	 * If the glob returns a single match, which is the same as the
	 * input glob, and it is a directory, then just list its contents
	 */
	if (g.gl_pathc == 1 &&
	    strncmp(path, g.gl_pathv[0], strlen(g.gl_pathv[0]) - 1) == 0) {
		if ((a = do_lstat(conn, path, 1)) == NULL) {
			globfree(&g);
	    		return (-1);
		}
		if ((a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) &&
		    S_ISDIR(a->perm)) {
			globfree(&g);
			return (do_ls_dir(conn, path, strip_path, lflag));
		}
	}

	if (!(lflag & SHORT_VIEW)) {
		int m = 0, width = 80;
		struct winsize ws;	

		/* Count entries for sort and find longest filename */
 		for (i = 0; g.gl_pathv[i]; i++)
			m = MAX(m, strlen(g.gl_pathv[i]));

		if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) != -1)
			width = ws.ws_col;

		columns = width / (m + 2);
		colspace = width / columns;
	}

	for (i = 0; g.gl_pathv[i]; i++) {
		char *fname;

		fname = path_strip(g.gl_pathv[i], strip_path);

		if (lflag & LONG_VIEW) {
			char *lname;
			struct stat sb;

			/*
			 * XXX: this is slow - 1 roundtrip per path
			 * A solution to this is to fork glob() and
			 * build a sftp specific version which keeps the
			 * attribs (which currently get thrown away)
			 * that the server returns as well as the filenames.
			 */
			memset(&sb, 0, sizeof(sb));
			a = do_lstat(conn, g.gl_pathv[i], 1);
			if (a != NULL)
				attrib_to_stat(a, &sb);
			lname = ls_file(fname, &sb, 1);
			printf("%s\n", lname);
			xfree(lname);
		} else {
			printf("%-*s", colspace, fname);
			if (c >= columns) {
				printf("\n");
				c = 1;
			} else
				c++;
		}
		xfree(fname);
	}

	if (!(lflag & LONG_VIEW) && (c != 1))
		printf("\n");

	if (g.gl_pathc)
		globfree(&g);

	return (0);
}

static int
parse_args(const char **cpp, int *pflag, int *lflag, int *iflag,
    unsigned long *n_arg, char **path1, char **path2)
{
	const char *cmd, *cp = *cpp;
	char *cp2;
	int base = 0;
	long l;
	int i, cmdnum;

	/* Skip leading whitespace */
	cp = cp + strspn(cp, WHITESPACE);

	/* Ignore blank lines and lines which begin with comment '#' char */
	if (*cp == '\0' || *cp == '#')
		return (0);

	/* Check for leading '-' (disable error processing) */
	*iflag = 0;
	if (*cp == '-') {
		*iflag = 1;
		cp++;
	}
		
	/* Figure out which command we have */
	for (i = 0; cmds[i].c; i++) {
		int cmdlen = strlen(cmds[i].c);

		/* Check for command followed by whitespace */
		if (!strncasecmp(cp, cmds[i].c, cmdlen) &&
		    strchr(WHITESPACE, cp[cmdlen])) {
			cp += cmdlen;
			cp = cp + strspn(cp, WHITESPACE);
			break;
		}
	}
	cmdnum = cmds[i].n;
	cmd = cmds[i].c;

	/* Special case */
	if (*cp == '!') {
		cp++;
		cmdnum = I_SHELL;
	} else if (cmdnum == -1) {
		error("Invalid command.");
		return (-1);
	}

	/* Get arguments and parse flags */
	*lflag = *pflag = *n_arg = 0;
	*path1 = *path2 = NULL;
	switch (cmdnum) {
	case I_GET:
	case I_PUT:
		if (parse_getput_flags(&cp, pflag))
			return(-1);
		/* Get first pathname (mandatory) */
		if (get_pathname(&cp, path1))
			return(-1);
		if (*path1 == NULL) {
			error("You must specify at least one path after a "
			    "%s command.", cmd);
			return(-1);
		}
		/* Try to get second pathname (optional) */
		if (get_pathname(&cp, path2))
			return(-1);
		break;
	case I_RENAME:
	case I_SYMLINK:
		if (get_pathname(&cp, path1))
			return(-1);
		if (get_pathname(&cp, path2))
			return(-1);
		if (!*path1 || !*path2) {
			error("You must specify two paths after a %s "
			    "command.", cmd);
			return(-1);
		}
		break;
	case I_RM:
	case I_MKDIR:
	case I_RMDIR:
	case I_CHDIR:
	case I_LCHDIR:
	case I_LMKDIR:
		/* Get pathname (mandatory) */
		if (get_pathname(&cp, path1))
			return(-1);
		if (*path1 == NULL) {
			error("You must specify a path after a %s command.",
			    cmd);
			return(-1);
		}
		break;
	case I_LS:
		if (parse_ls_flags(&cp, lflag))
			return(-1);
		/* Path is optional */
		if (get_pathname(&cp, path1))
			return(-1);
		break;
	case I_LLS:
	case I_SHELL:
		/* Uses the rest of the line */
		break;
	case I_LUMASK:
		base = 8;
	case I_CHMOD:
		base = 8;
	case I_CHOWN:
	case I_CHGRP:
		/* Get numeric arg (mandatory) */
		l = strtol(cp, &cp2, base);
		if (cp2 == cp || ((l == LONG_MIN || l == LONG_MAX) &&
		    errno == ERANGE) || l < 0) {
			error("You must supply a numeric argument "
			    "to the %s command.", cmd);
			return(-1);
		}
		cp = cp2;
		*n_arg = l;
		if (cmdnum == I_LUMASK && strchr(WHITESPACE, *cp))
			break;
		if (cmdnum == I_LUMASK || !strchr(WHITESPACE, *cp)) {
			error("You must supply a numeric argument "
			    "to the %s command.", cmd);
			return(-1);
		}
		cp += strspn(cp, WHITESPACE);

		/* Get pathname (mandatory) */
		if (get_pathname(&cp, path1))
			return(-1);
		if (*path1 == NULL) {
			error("You must specify a path after a %s command.",
			    cmd);
			return(-1);
		}
		break;
	case I_QUIT:
	case I_PWD:
	case I_LPWD:
	case I_HELP:
	case I_VERSION:
	case I_PROGRESS:
		break;
	default:
		fatal("Command not implemented");
	}

	*cpp = cp;
	return(cmdnum);
}

static int
parse_dispatch_command(struct sftp_conn *conn, const char *cmd, char **pwd,
    int err_abort)
{
	char *path1, *path2, *tmp;
	int pflag, lflag, iflag, cmdnum, i;
	unsigned long n_arg;
	Attrib a, *aa;
	char path_buf[MAXPATHLEN];
	int err = 0;
	glob_t g;

	path1 = path2 = NULL;
	cmdnum = parse_args(&cmd, &pflag, &lflag, &iflag, &n_arg,
	    &path1, &path2);

	if (iflag != 0)
		err_abort = 0;

	memset(&g, 0, sizeof(g));

	/* Perform command */
	switch (cmdnum) {
	case 0:
		/* Blank line */
		break;
	case -1:
		/* Unrecognized command */
		err = -1;
		break;
	case I_GET:
		err = process_get(conn, path1, path2, *pwd, pflag);
		break;
	case I_PUT:
		err = process_put(conn, path1, path2, *pwd, pflag);
		break;
	case I_RENAME:
		path1 = make_absolute(path1, *pwd);
		path2 = make_absolute(path2, *pwd);
		err = do_rename(conn, path1, path2);
		break;
	case I_SYMLINK:
		path2 = make_absolute(path2, *pwd);
		err = do_symlink(conn, path1, path2);
		break;
	case I_RM:
		path1 = make_absolute(path1, *pwd);
		remote_glob(conn, path1, GLOB_NOCHECK, NULL, &g);
		for (i = 0; g.gl_pathv[i]; i++) {
			printf("Removing %s\n", g.gl_pathv[i]);
			err = do_rm(conn, g.gl_pathv[i]);
			if (err != 0 && err_abort)
				break;
		}
		break;
	case I_MKDIR:
		path1 = make_absolute(path1, *pwd);
		attrib_clear(&a);
		a.flags |= SSH2_FILEXFER_ATTR_PERMISSIONS;
		a.perm = 0777;
		err = do_mkdir(conn, path1, &a);
		break;
	case I_RMDIR:
		path1 = make_absolute(path1, *pwd);
		err = do_rmdir(conn, path1);
		break;
	case I_CHDIR:
		path1 = make_absolute(path1, *pwd);
		if ((tmp = do_realpath(conn, path1)) == NULL) {
			err = 1;
			break;
		}
		if ((aa = do_stat(conn, tmp, 0)) == NULL) {
			xfree(tmp);
			err = 1;
			break;
		}
		if (!(aa->flags & SSH2_FILEXFER_ATTR_PERMISSIONS)) {
			error("Can't change directory: Can't check target");
			xfree(tmp);
			err = 1;
			break;
		}
		if (!S_ISDIR(aa->perm)) {
			error("Can't change directory: \"%s\" is not "
			    "a directory", tmp);
			xfree(tmp);
			err = 1;
			break;
		}
		xfree(*pwd);
		*pwd = tmp;
		break;
	case I_LS:
		if (!path1) {
			do_globbed_ls(conn, *pwd, *pwd, lflag);
			break;
		}

		/* Strip pwd off beginning of non-absolute paths */
		tmp = NULL;
		if (*path1 != '/')
			tmp = *pwd;

		path1 = make_absolute(path1, *pwd);
		err = do_globbed_ls(conn, path1, tmp, lflag);
		break;
	case I_LCHDIR:
		if (chdir(path1) == -1) {
			error("Couldn't change local directory to "
			    "\"%s\": %s", path1, strerror(errno));
			err = 1;
		}
		break;
	case I_LMKDIR:
		if (mkdir(path1, 0777) == -1) {
			error("Couldn't create local directory "
			    "\"%s\": %s", path1, strerror(errno));
			err = 1;
		}
		break;
	case I_LLS:
		local_do_ls(cmd);
		break;
	case I_SHELL:
		local_do_shell(cmd);
		break;
	case I_LUMASK:
		umask(n_arg);
		printf("Local umask: %03lo\n", n_arg);
		break;
	case I_CHMOD:
		path1 = make_absolute(path1, *pwd);
		attrib_clear(&a);
		a.flags |= SSH2_FILEXFER_ATTR_PERMISSIONS;
		a.perm = n_arg;
		remote_glob(conn, path1, GLOB_NOCHECK, NULL, &g);
		for (i = 0; g.gl_pathv[i]; i++) {
			printf("Changing mode on %s\n", g.gl_pathv[i]);
			err = do_setstat(conn, g.gl_pathv[i], &a);
			if (err != 0 && err_abort)
				break;
		}
		break;
	case I_CHOWN:
	case I_CHGRP:
		path1 = make_absolute(path1, *pwd);
		remote_glob(conn, path1, GLOB_NOCHECK, NULL, &g);
		for (i = 0; g.gl_pathv[i]; i++) {
			if (!(aa = do_stat(conn, g.gl_pathv[i], 0))) {
				if (err != 0 && err_abort)
					break;
				else
					continue;
			}
			if (!(aa->flags & SSH2_FILEXFER_ATTR_UIDGID)) {
				error("Can't get current ownership of "
				    "remote file \"%s\"", g.gl_pathv[i]);
				if (err != 0 && err_abort)
					break;
				else
					continue;
			}
			aa->flags &= SSH2_FILEXFER_ATTR_UIDGID;
			if (cmdnum == I_CHOWN) {
				printf("Changing owner on %s\n", g.gl_pathv[i]);
				aa->uid = n_arg;
			} else {
				printf("Changing group on %s\n", g.gl_pathv[i]);
				aa->gid = n_arg;
			}
			err = do_setstat(conn, g.gl_pathv[i], aa);
			if (err != 0 && err_abort)
				break;
		}
		break;
	case I_PWD:
		printf("Remote working directory: %s\n", *pwd);
		break;
	case I_LPWD:
		if (!getcwd(path_buf, sizeof(path_buf))) {
			error("Couldn't get local cwd: %s", strerror(errno));
			err = -1;
			break;
		}
		printf("Local working directory: %s\n", path_buf);
		break;
	case I_QUIT:
		/* Processed below */
		break;
	case I_HELP:
		help();
		break;
	case I_VERSION:
		printf("SFTP protocol version %u\n", sftp_proto_version(conn));
		break;
	case I_PROGRESS:
		showprogress = !showprogress;
		if (showprogress)
			printf("Progress meter enabled\n");
		else
			printf("Progress meter disabled\n");
		break;
	default:
		fatal("%d is not implemented", cmdnum);
	}

	if (g.gl_pathc)
		globfree(&g);
	if (path1)
		xfree(path1);
	if (path2)
		xfree(path2);

	/* If an unignored error occurs in batch mode we should abort. */
	if (err_abort && err != 0)
		return (-1);
	else if (cmdnum == I_QUIT)
		return (1);

	return (0);
}

int
interactive_loop(int fd_in, int fd_out, char *file1, char *file2)
{
	char *pwd;
	char *dir = NULL;
	char cmd[2048];
	struct sftp_conn *conn;
	int err;

	conn = do_init(fd_in, fd_out, copy_buffer_len, num_requests);
	if (conn == NULL)
		fatal("Couldn't initialise connection to server");

	pwd = do_realpath(conn, ".");
	if (pwd == NULL)
		fatal("Need cwd");

	if (file1 != NULL) {
		dir = xstrdup(file1);
		dir = make_absolute(dir, pwd);

		if (remote_is_dir(conn, dir) && file2 == NULL) {
			printf("Changing to: %s\n", dir);
			snprintf(cmd, sizeof cmd, "cd \"%s\"", dir);
			if (parse_dispatch_command(conn, cmd, &pwd, 1) != 0)
				return (-1);
		} else {
			if (file2 == NULL)
				snprintf(cmd, sizeof cmd, "get %s", dir);
			else
				snprintf(cmd, sizeof cmd, "get %s %s", dir,
				    file2);

			err = parse_dispatch_command(conn, cmd, &pwd, 1);
			xfree(dir);
			xfree(pwd);
			return (err);
		}
		xfree(dir);
	}

#if HAVE_SETVBUF
	setvbuf(stdout, NULL, _IOLBF, 0);
	setvbuf(infile, NULL, _IOLBF, 0);
#else
	setlinebuf(stdout);
	setlinebuf(infile);
#endif

	err = 0;
	for (;;) {
		char *cp;

		printf("sftp> ");

		/* XXX: use libedit */
		if (fgets(cmd, sizeof(cmd), infile) == NULL) {
			printf("\n");
			break;
		} else if (infile != stdin) /* Bluff typing */
			printf("%s", cmd);

		cp = strrchr(cmd, '\n');
		if (cp)
			*cp = '\0';

		err = parse_dispatch_command(conn, cmd, &pwd, infile != stdin);
		if (err != 0)
			break;
	}
	xfree(pwd);

	/* err == 1 signifies normal "quit" exit */
	return (err >= 0 ? 0 : -1);
}