[PATCH 5/5] python: qmp_shell: handle comment lines and escaped eol

[Damien Hedde]

In order to support more user-friendly command list file,
this commit adds the support for:
+ comment lines: line staring by '#' are ignored
+ escaped enf-of-line: line with trailing ' \' are continued
  on next one

For eol: we impose a space before the '\' in order not to trigger
the escape if the '\' is for example at the end of a value in a
'key=value' sequence.
Althought it does not have any real interest in interactive mode,
the prompt is adapted when in that case.

Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>
---
 python/qemu/aqmp/qmp_shell.py | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/python/qemu/aqmp/qmp_shell.py b/python/qemu/aqmp/qmp_shell.py
index dd38ef8a13..64cd31dcd6 100644
--- a/python/qemu/aqmp/qmp_shell.py
+++ b/python/qemu/aqmp/qmp_shell.py
@@ -188,6 +188,7 @@ def __init__(self, address: SocketAddrT,
         self._greeting: Optional[QMPMessage] = None
         self._completer = QMPCompleter()
         self._transmode = False
+        self._escaped_eol = False
         self._actions: List[QMPMessage] = []
         self._histfile = os.path.join(os.path.expanduser('~'),
                                       '.qmp-shell_history')
@@ -385,6 +386,8 @@ def prompt(self) -> str:
         """
         if not sys.stdin.isatty():
             return ""
+        if self._escaped_eol:
+            return '> '
         if self._transmode:
             return 'TRANS> '
         return '(QEMU) '
@@ -397,6 +400,11 @@ def read_exec_command(self) -> bool:
         """
         try:
             cmdline = input(self.prompt)
+            self._escaped_eol = True
+            while cmdline[-2:] == ' \\':
+                #only remove the trailing '\', keep the space
+                cmdline = cmdline[:-1] + input(self.prompt)
+            self._escaped_eol = False
         except EOFError:
             print()
             return False
@@ -406,6 +414,10 @@ def read_exec_command(self) -> bool:
                 print(event)
             return True
 
+        if cmdline[0] == '#':
+            #consider these lines as comments
+            return True
+
         if self.raise_error:
             resp = self._execute_cmd(cmdline)
             if resp and 'error' in resp:
-- 
2.35.1