Re: [Qemu-devel] [PATCH v2 03/11] trace: [tracetool] Simplify event line parsing

[Harsh Bora <harsh@linux.vnet.ibm.com>]

Hi Lluis,
Sorry for a late response as I was out of office for last 2 weeks 
because of some medical emergency at home. While trying to merge your 
changes with mine, I found something (see below):

On 02/04/2012 02:41 AM, Lluís Vilanova wrote:
> Signed-off-by: Lluís Vilanova<vilanova@ac.upc.edu>
> ---
>   scripts/tracetool.py |   46 ++++++++++++++--------------------------------
>   1 files changed, 14 insertions(+), 32 deletions(-)
>
> diff --git a/scripts/tracetool.py b/scripts/tracetool.py
> index 7042728..f675d96 100755
> --- a/scripts/tracetool.py
> +++ b/scripts/tracetool.py
> @@ -38,19 +38,9 @@ Options:
>   '''
>       sys.exit(1)
>
> -def get_name(line, sep='('):
> -    head, sep, tail = line.partition(sep)
> -    return head
> -
> -def get_args(line, sep1='(', sep2=')'):
> -    head, sep1, tail = line.partition(sep1)
> -    args, sep2, fmt_str = tail.partition(sep2)
> -    return args
> -
> -def get_argnames(line, sep=','):
> +def get_argnames(args):
>       nfields = 0
>       str = []
> -    args = get_args(line)
>       for field in args.split():
>         nfields = nfields + 1
>         # Drop pointer star
> @@ -71,21 +61,7 @@ def get_argnames(line, sep=','):
>       else:
>         return ''
>
> -def get_argc(line):
> -    argc = 0
> -    argnames = get_argnames(line)
> -    if argnames:
> -      for name in argnames.split(','):
> -        argc = argc + 1
> -    return argc
> -
> -def get_fmt(line, sep=')'):
> -    event, sep, fmt = line.partition(sep)
> -    return fmt
> -
> -def calc_sizeofargs(line):
> -    args = get_args(line)
> -    argc = get_argc(line)
> +def calc_sizeofargs(args, argc):
>       strtype = ('const char*', 'char*', 'const char *', 'char *')
>       str = []
>       newstr = ""
> @@ -495,16 +471,22 @@ trace_gen = {
>   }
>
>   # A trace event
> +import re
> +cre = re.compile("(?P<name>[^(\s]+)\((?P<args>[^)]*)\)\s*(?P<fmt>\".*)?")
> +
>   class Event(object):
>       def __init__(self, num, line):
>           self.num = num
> -        self.args = get_args(line)
> +        m = cre.match(line)
> +        assert m is not None
> +        groups = m.groupdict('')
> +        self.args = groups["args"]
>           self.arglist = self.args.split(',')
> -        self.name = get_name(line)
> -        self.argc = get_argc(line)
> -        self.argnames = get_argnames(line)
> -        self.sizestr = calc_sizeofargs(line)
> -        self.fmt = get_fmt(line)
> +        self.name = groups["name"]
> +        self.argc = len(self.arglist)

for events with only 'void' as argument, it calculates argc as 1 which
should be 0 only. Previous code does take care of 'void' arguments. Do
you have a better replacement for the previous code taking care of this?

- Harsh


> +        self.argnames = get_argnames(self.args)
> +        self.sizestr = calc_sizeofargs(self.args, self.argc)
> +        self.fmt = groups["fmt"]
>
>   # Generator that yields Event objects given a trace-events file object
>   def read_events(fobj):
>