sftp: Be a bit more clever about completions

There are commands (e.g. "get" or "put") that accept two
arguments, a local path and a remote path. However, the way
current completion is written doesn't take this distinction into
account and always completes remote or local paths.

By expanding CMD struct and "cmds" array this distinction can be
reflected and with small adjustment to completer code the correct
path can be completed.

By Michal Privoznik, ok dtucker@

diff --git a/usr.bin/ssh/sftp.c b/usr.bin/ssh/sftp.c
index d49f168..c4e63af 100644 (file)
--- a/usr.bin/ssh/sftp.c
+++ b/usr.bin/ssh/sftp.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sftp.c,v 1.219 2022/09/16 03:13:34 djm Exp $ */
+/* $OpenBSD: sftp.c,v 1.220 2022/09/16 03:33:14 djm Exp $ */
 /*
  * Copyright (c) 2001-2004 Damien Miller <djm@openbsd.org>
  *
@@ -145,7 +145,8 @@ enum sftp_command {
 struct CMD {
        const char *c;
        const int n;
-       const int t;
+       const int t;    /* Completion type for the first argument */
+       const int t2;   /* completion type for the optional second argument */
 };
 
 /* Type of completion */
@@ -154,44 +155,44 @@ struct CMD {
 #define LOCAL  2
 
 static const struct CMD cmds[] = {
-       { "bye",        I_QUIT,         NOARGS  },
-       { "cd",         I_CHDIR,        REMOTE  },
-       { "chdir",      I_CHDIR,        REMOTE  },
-       { "chgrp",      I_CHGRP,        REMOTE  },
-       { "chmod",      I_CHMOD,        REMOTE  },
-       { "chown",      I_CHOWN,        REMOTE  },
-       { "copy",       I_COPY,         REMOTE  },
-       { "cp",         I_COPY,         REMOTE  },
-       { "df",         I_DF,           REMOTE  },
-       { "dir",        I_LS,           REMOTE  },
-       { "exit",       I_QUIT,         NOARGS  },
-       { "get",        I_GET,          REMOTE  },
-       { "help",       I_HELP,         NOARGS  },
-       { "lcd",        I_LCHDIR,       LOCAL   },
-       { "lchdir",     I_LCHDIR,       LOCAL   },
-       { "lls",        I_LLS,          LOCAL   },
-       { "lmkdir",     I_LMKDIR,       LOCAL   },
-       { "ln",         I_LINK,         REMOTE  },
-       { "lpwd",       I_LPWD,         LOCAL   },
-       { "ls",         I_LS,           REMOTE  },
-       { "lumask",     I_LUMASK,       NOARGS  },
-       { "mkdir",      I_MKDIR,        REMOTE  },
-       { "mget",       I_GET,          REMOTE  },
-       { "mput",       I_PUT,          LOCAL   },
-       { "progress",   I_PROGRESS,     NOARGS  },
-       { "put",        I_PUT,          LOCAL   },
-       { "pwd",        I_PWD,          REMOTE  },
-       { "quit",       I_QUIT,         NOARGS  },
-       { "reget",      I_REGET,        REMOTE  },
-       { "rename",     I_RENAME,       REMOTE  },
-       { "reput",      I_REPUT,        LOCAL   },
-       { "rm",         I_RM,           REMOTE  },
-       { "rmdir",      I_RMDIR,        REMOTE  },
-       { "symlink",    I_SYMLINK,      REMOTE  },
-       { "version",    I_VERSION,      NOARGS  },
-       { "!",          I_SHELL,        NOARGS  },
-       { "?",          I_HELP,         NOARGS  },
-       { NULL,         -1,             -1      }
+       { "bye",        I_QUIT,         NOARGS,         NOARGS  },
+       { "cd",         I_CHDIR,        REMOTE,         NOARGS  },
+       { "chdir",      I_CHDIR,        REMOTE,         NOARGS  },
+       { "chgrp",      I_CHGRP,        REMOTE,         NOARGS  },
+       { "chmod",      I_CHMOD,        REMOTE,         NOARGS  },
+       { "chown",      I_CHOWN,        REMOTE,         NOARGS  },
+       { "copy",       I_COPY,         REMOTE,         LOCAL   },
+       { "cp",         I_COPY,         REMOTE,         LOCAL   },
+       { "df",         I_DF,           REMOTE,         NOARGS  },
+       { "dir",        I_LS,           REMOTE,         NOARGS  },
+       { "exit",       I_QUIT,         NOARGS,         NOARGS  },
+       { "get",        I_GET,          REMOTE,         LOCAL   },
+       { "help",       I_HELP,         NOARGS,         NOARGS  },
+       { "lcd",        I_LCHDIR,       LOCAL,          NOARGS  },
+       { "lchdir",     I_LCHDIR,       LOCAL,          NOARGS  },
+       { "lls",        I_LLS,          LOCAL,          NOARGS  },
+       { "lmkdir",     I_LMKDIR,       LOCAL,          NOARGS  },
+       { "ln",         I_LINK,         REMOTE,         REMOTE  },
+       { "lpwd",       I_LPWD,         LOCAL,          NOARGS  },
+       { "ls",         I_LS,           REMOTE,         NOARGS  },
+       { "lumask",     I_LUMASK,       NOARGS,         NOARGS  },
+       { "mkdir",      I_MKDIR,        REMOTE,         NOARGS  },
+       { "mget",       I_GET,          REMOTE,         LOCAL   },
+       { "mput",       I_PUT,          LOCAL,          REMOTE  },
+       { "progress",   I_PROGRESS,     NOARGS,         NOARGS  },
+       { "put",        I_PUT,          LOCAL,          REMOTE  },
+       { "pwd",        I_PWD,          REMOTE,         NOARGS  },
+       { "quit",       I_QUIT,         NOARGS,         NOARGS  },
+       { "reget",      I_REGET,        REMOTE,         LOCAL   },
+       { "rename",     I_RENAME,       REMOTE,         REMOTE  },
+       { "reput",      I_REPUT,        LOCAL,          REMOTE  },
+       { "rm",         I_RM,           REMOTE,         NOARGS  },
+       { "rmdir",      I_RMDIR,        REMOTE,         NOARGS  },
+       { "symlink",    I_SYMLINK,      REMOTE,         REMOTE  },
+       { "version",    I_VERSION,      NOARGS,         NOARGS  },
+       { "!",          I_SHELL,        NOARGS,         NOARGS  },
+       { "?",          I_HELP,         NOARGS,         NOARGS  },
+       { NULL,         -1,             -1,             -1      }
 };
 
 /* ARGSUSED */
@@ -1917,19 +1918,25 @@ complete_cmd_parse(EditLine *el, char *cmd, int lastarg, char quote,
 }
 
 /*
- * Determine whether a particular sftp command's arguments (if any)
- * represent local or remote files.
+ * Determine whether a particular sftp command's arguments (if any) represent
+ * local or remote files. The "cmdarg" argument specifies the actual argument
+ * and accepts values 1 or 2.
  */
 static int
-complete_is_remote(char *cmd) {
+complete_is_remote(char *cmd, int cmdarg) {
        int i;
 
        if (cmd == NULL)
                return -1;
 
        for (i = 0; cmds[i].c; i++) {
-               if (!strncasecmp(cmd, cmds[i].c, strlen(cmds[i].c)))
-                       return cmds[i].t;
+               if (!strncasecmp(cmd, cmds[i].c, strlen(cmds[i].c))) {
+                       if (cmdarg == 1)
+                               return cmds[i].t;
+                       else if (cmdarg == 2)
+                               return cmds[i].t2;
+                       break;
+               }
        }
 
        return -1;
@@ -2109,12 +2116,28 @@ complete(EditLine *el, int ch)
                        ret = CC_REDISPLAY;
        } else if (carg >= 1) {
                /* Handle file parsing */
-               int remote = complete_is_remote(argv[0]);
+               int remote = 0;
+               int i = 0, cmdarg = 0;
                char *filematch = NULL;
 
                if (carg > 1 && line[cursor-1] != ' ')
                        filematch = argv[carg - 1];
 
+               for (i = 1; i < carg; i++) {
+                       /* Skip flags */
+                       if (argv[i][0] != '-')
+                               cmdarg++;
+               }
+
+               /*
+                * If previous argument is complete, then offer completion
+                * on the next one.
+                */
+               if (line[cursor - 1] == ' ')
+                       cmdarg++;
+
+               remote = complete_is_remote(argv[0], cmdarg);
+
                if ((remote == REMOTE || remote == LOCAL) &&
                    complete_match(el, complete_ctx->conn,
                    *complete_ctx->remote_pathp, filematch,