qapi: Clean up cgen() and mcgen()

Commit 05dfb26 added eatspace stripping to mcgen().  Move it to
cgen(), just in case somebody gets tempted to use cgen() directly
instead of via mcgen().

cgen() indents blank lines.  No such lines get generated right now,
but fix it anyway.

We use triple-quoted strings for program text, like this:

    '''
    Program text
    any number of lines
    '''

Keeps the program text relatively readable, but puts an extra newline
at either end.  mcgen() "fixes" that by dropping the first and last
line outright.  Drop only the newlines.

This unmasks a bug in qapi-commands.py: four quotes instead of three.
Fix it up.

Output doesn't change

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

diff --git a/scripts/qapi-commands.py b/scripts/qapi-commands.py
index ca22acc1d5ef4fd981f524a2395c726ca50cdde5..ce5140865b29b5467eb89c1a7dce281ccac5785b 100644 (file)
--- a/scripts/qapi-commands.py
+++ b/scripts/qapi-commands.py
@@ -56,7 +56,7 @@ def gen_sync_call(name, args, ret_type, indent=0):
                 name=c_name(name), args=arglist, retval=retval).rstrip()
     if ret_type:
         ret += "\n" + gen_err_check('local_err')
-        ret += "\n" + mcgen(''''
+        ret += "\n" + mcgen('''
 %(marshal_output_call)s
 ''',
                             marshal_output_call=gen_marshal_output_call(name, ret_type)).rstrip()

diff --git a/scripts/qapi.py b/scripts/qapi.py
index 06d7fc2848fac96b176d8e797e90f9b2bea7c7fb..e656beb58b4604c3991576afd0378e6972cd8b29 100644 (file)
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -943,15 +943,20 @@ def pop_indent(indent_amount=4):
     global indent_level
     indent_level -= indent_amount
 
+# Generate @code with @kwds interpolated.
+# Obey indent_level, and strip eatspace.
 def cgen(code, **kwds):
-    indent = genindent(indent_level)
-    lines = code.split('\n')
-    lines = map(lambda x: indent + x, lines)
-    return '\n'.join(lines) % kwds + '\n'
+    raw = code % kwds
+    if indent_level:
+        indent = genindent(indent_level)
+        raw = re.subn("^.", indent + r'\g<0>', raw, 0, re.MULTILINE)
+        raw = raw[0]
+    return re.sub(re.escape(eatspace) + ' *', '', raw)
 
 def mcgen(code, **kwds):
-    raw = cgen('\n'.join(code.split('\n')[1:-1]), **kwds)
-    return re.sub(re.escape(eatspace) + ' *', '', raw)
+    if code[0] == '\n':
+        code = code[1:]
+    return cgen(code, **kwds)
 
 def basename(filename):
     return filename.split("/")[-1]