[PATCH v7 1/4] monitor/hmp: add support for flag argument with value

[Stefan Reiter <s.reiter@proxmox.com>]

Adds support for the "-xV" parameter type, where "-x" denotes a flag
name and the "V" suffix indicates that this flag is supposed to take an
arbitrary string parameter.

These parameters are always optional, the entry in the qdict will be
omitted if the flag is not given.

Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
---

v6:
It wasn't possible to pass the 'connected' parameter to set_password, since the
code to handle optional parameters couldn't live with a different param (not
starting with '-') coming up instead - fix that by advancing over the 'value
flag' modifier in case `*p != '-'`.

Also change the modifier to 'V' instead of 'S' so it can be distinguished from
an actual trailing 'S' type param.

Discovered in testing. I dropped Eric's R-b due to the code change.

 monitor/hmp.c              | 19 ++++++++++++++++++-
 monitor/monitor-internal.h |  3 ++-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/monitor/hmp.c b/monitor/hmp.c
index d50c3124e1..899e0c990f 100644
--- a/monitor/hmp.c
+++ b/monitor/hmp.c
@@ -980,6 +980,7 @@ static QDict *monitor_parse_arguments(Monitor *mon,
             {
                 const char *tmp = p;
                 int skip_key = 0;
+                int ret;
                 /* option */
 
                 c = *typestr++;
@@ -1002,11 +1003,27 @@ static QDict *monitor_parse_arguments(Monitor *mon,
                     }
                     if (skip_key) {
                         p = tmp;
+                    } else if (*typestr == 'V') {
+                        /* has option with string value */
+                        typestr++;
+                        tmp = p++;
+                        while (qemu_isspace(*p)) {
+                            p++;
+                        }
+                        ret = get_str(buf, sizeof(buf), &p);
+                        if (ret < 0) {
+                            monitor_printf(mon, "%s: value expected for -%c\n",
+                                           cmd->name, *tmp);
+                            goto fail;
+                        }
+                        qdict_put_str(qdict, key, buf);
                     } else {
-                        /* has option */
+                        /* has boolean option */
                         p++;
                         qdict_put_bool(qdict, key, true);
                     }
+                } else if (*typestr == 'V') {
+                    typestr++;
                 }
             }
             break;
diff --git a/monitor/monitor-internal.h b/monitor/monitor-internal.h
index 9c3a09cb01..9e708b329d 100644
--- a/monitor/monitor-internal.h
+++ b/monitor/monitor-internal.h
@@ -63,7 +63,8 @@
  * '.'          other form of optional type (for 'i' and 'l')
  * 'b'          boolean
  *              user mode accepts "on" or "off"
- * '-'          optional parameter (eg. '-f')
+ * '-'          optional parameter (eg. '-f'); if followed by an 'V', it
+ *              specifies an optional string param (e.g. '-fV' allows '-f foo')
  *
  */
 
-- 
2.30.2