libxcmd: merge command() and iterate_command()

Simplify the command loop further by merging the command loop
iteration checks with the command execution function. This removes
all visibility of command iteration from the main command execution
loop, and enables us to factor and clean up the command loop
processing neatly.

[ sandeen: align process_input() args ]

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

diff --git a/libxcmd/command.c b/libxcmd/command.c
index 789aeb5c5e5ab9444219f3d0f7072d093f7a18bf..03fb219e936500a198d524848fe7adcfaff9692e 100644 (file)
--- a/libxcmd/command.c
+++ b/libxcmd/command.c
@@ -125,22 +125,30 @@ add_user_command(char *optarg)
 }
 
 /*
- * To detect one-shot commands, they will return a negative index. If we
- * get a negative index on entry, we've already run the one-shot command,
- * so we abort straight away.
+ * Run a command, iterating as necessary. Return 0 for success, non-zero
+ * if an error occurred. Errors terminate loop iteration immediately.
  */
 static int
 iterate_command(
        const cmdinfo_t *ct,
-       int             index)
+       int             argc,
+       char            **argv)
 {
-       if (index < 0)
+       int             error = 0;
+       int             j;
+
+       /* if there's nothing to iterate, we're done! */
+       if (!iter_func)
                return 0;
-       if (ct->flags & CMD_FLAG_ONESHOT)
-               return -1;
-       if (iter_func)
-               return iter_func(index);
-       return 0;
+
+       for (j = iter_func(0); j; j = iter_func(j)) {
+               error = command(ct, argc, argv);
+               if (error)
+                       break;
+
+       }
+
+       return error;
 }
 
 void
@@ -150,14 +158,55 @@ add_command_iterator(
        iter_func = func;
 }
 
-void
-command_loop(void)
+static int
+process_input(
+       char            *input,
+       bool            iterate)
 {
-       int             c, i, j = 0, done = 0;
-       char            *input;
        char            **v;
        const cmdinfo_t *ct;
+       int             c = 0;
+       int             error = 0;
+
+       v = breakline(input, &c);
+       if (!c)
+               goto out;
+
+       ct = find_command(v[0]);
+       if (!ct) {
+               fprintf(stderr, _("command \"%s\" not found\n"), v[0]);
+               goto out;
+       }
+
+       /* oneshot commands don't iterate */
+       if (!iterate || (ct->flags & CMD_FLAG_ONESHOT))
+               error = command(ct, c, v);
+       else
+               error = iterate_command(ct, c, v);
+out:
+       doneline(input, v);
+       return error;
+}
+
+void
+command_loop(void)
+{
+       char    *input;
+       int     done = 0;
+       int     i;
+
+       if (!cmdline) {
+               /* interactive mode */
+               while (!done) {
+                       input = fetchline();
+                       if (!input)
+                               break;
+                       done = process_input(input, false);
+               }
+               return;
+       }
 
+       /* command line mode */
        for (i = 0; !done && i < ncmdline; i++) {
                input = strdup(cmdline[i]);
                if (!input) {
@@ -166,37 +215,10 @@ command_loop(void)
                                cmdline[i], strerror(errno));
                        exit(1);
                }
-               v = breakline(input, &c);
-               if (c) {
-                       ct = find_command(v[0]);
-                       if (ct) {
-                               j = 0;
-                               while (!done && (j = iterate_command(ct, j)))
-                                       done = command(ct, c, v);
-                       } else
-                               fprintf(stderr, _("command \"%s\" not found\n"),
-                                       v[0]);
-               }
-               doneline(input, v);
-       }
-       if (cmdline) {
-               free(cmdline);
-               return;
-       }
-       while (!done) {
-               if ((input = fetchline()) == NULL)
-                       break;
-               v = breakline(input, &c);
-               if (c) {
-                       ct = find_command(v[0]);
-                       if (ct)
-                               done = command(ct, c, v);
-                       else
-                               fprintf(stderr, _("command \"%s\" not found\n"),
-                                       v[0]);
-               }
-               doneline(input, v);
+               done = process_input(input, true);
        }
+       free(cmdline);
+       return;
 }
 
 void