Re: [Qemu-devel] [PATCH 1/2] blockdev: Add dynamic generation of module_block.h

[Colin Lord <clord@redhat.com>]

On 06/16/2016 12:59 AM, Fam Zheng wrote:
> On Wed, 06/15 14:40, Colin Lord wrote:
>> From: Marc Mari <address@hidden>
>>
>> To simplify the addition of new block modules, add a script that generates
>> include/qemu/module_block.h automatically from the modules' source code.
>>
>> This script assumes that the QEMU coding style rules are followed.
>>
>> Signed-off-by: Marc Marí <address@hidden>
>> Signed-off-by: Colin Lord <clord@redhat.com>
>> ---
>>  .gitignore                      |   1 +
>>  Makefile                        |   8 +++
>>  scripts/modules/module_block.py | 134 ++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 143 insertions(+)
>>  create mode 100644 scripts/modules/module_block.py
>>
>> diff --git a/.gitignore b/.gitignore
>> index 38ee1c5..06aa064 100644
>> --- a/.gitignore
>> +++ b/.gitignore
>> @@ -110,3 +110,4 @@ tags
>>  TAGS
>>  docker-src.*
>>  *~
>> +/include/qemu/module_block.h
>> diff --git a/Makefile b/Makefile
>> index ed4032a..8f8b6a2 100644
>> --- a/Makefile
>> +++ b/Makefile
>> @@ -76,6 +76,8 @@ GENERATED_HEADERS += trace/generated-ust-provider.h
>>  GENERATED_SOURCES += trace/generated-ust.c
>>  endif
>>  
>> +GENERATED_HEADERS += include/qemu/module_block.h
>> +
>>  # Don't try to regenerate Makefile or configure
>>  # We don't generate any of them
>>  Makefile: ;
>> @@ -352,6 +354,12 @@ ivshmem-client$(EXESUF): $(ivshmem-client-obj-y) libqemuutil.a libqemustub.a
>>  ivshmem-server$(EXESUF): $(ivshmem-server-obj-y) libqemuutil.a libqemustub.a
>>  	$(call LINK, $^)
>>  
>> +include/qemu/module_block.h: $(SRC_PATH)/scripts/modules/module_block.py config-host.mak
>> +	$(call quiet-command,$(PYTHON) \
>> +$(SRC_PATH)/scripts/modules/module_block.py \
>> +	$(SRC_PATH)/"./include/qemu/" $(addprefix $(SRC_PATH)/,$(patsubst %.mo,%.c,$(block-obj-m))), \
>> +	"  GEN   $@")
>> +
>>  clean:
>>  # avoid old build problems by removing potentially incorrect old files
>>  	rm -f config.mak op-i386.h opc-i386.h gen-op-i386.h op-arm.h opc-arm.h gen-op-arm.h
>> diff --git a/scripts/modules/module_block.py b/scripts/modules/module_block.py
>> new file mode 100644
>> index 0000000..005bc49
>> --- /dev/null
>> +++ b/scripts/modules/module_block.py
>> @@ -0,0 +1,134 @@
>> +#!/usr/bin/python
>> +#
>> +# Module information generator
>> +#
>> +# Copyright Red Hat, Inc. 2015
>> +#
>> +# Authors:
>> +#  Marc Mari <address@hidden>
> 
> Address hidden seems like a mistake during copy from web. :)
> 
> One more below..
> 

Yep, I didn't have the original emails (only the web archives) and I
didn't realize it wasn't supposed to look like that until I sent it out.
I'll fix it for the next version.

>> +#
>> +# This work is licensed under the terms of the GNU GPL, version 2.
>> +# See the COPYING file in the top-level directory.
>> +
>> +from __future__ import print_function
>> +import sys
>> +import os
>> +
>> +def get_string_struct(line):
>> +    data = line.split()
>> +
>> +    # data[0] -> struct element name
>> +    # data[1] -> =
>> +    # data[2] -> value
>> +
>> +    return data[2].replace('"', '')[:-1]
>> +
>> +def add_module(fhader, library, format_name, protocol_name,
>> +                probe, probe_device):
>> +    lines = []
>> +    lines.append('.library_name = "' + library + '",')
>> +    if format_name != "":
>> +        lines.append('.format_name = "' + format_name + '",')
>> +    if protocol_name != "":
>> +        lines.append('.protocol_name = "' + protocol_name + '",')
>> +    if probe:
>> +        lines.append('.has_probe = true,')
>> +    if probe_device:
>> +        lines.append('.has_probe_device = true,')
>> +
>> +    text = '\n\t'.join(lines)
>> +    fheader.write('\n\t{\n\t' + text + '\n\t},')
>> +
>> +def process_file(fheader, filename):
>> +    # This parser assumes the coding style rules are being followed
>> +    with open(filename, "r") as cfile:
>> +        found_something = False
>> +        found_start = False
>> +        library, _ = os.path.splitext(os.path.basename(filename))
>> +        for line in cfile:
>> +            if found_start:
>> +                line = line.replace('\n', '')
>> +                if line.find(".format_name") != -1:
>> +                    format_name = get_string_struct(line)
>> +                elif line.find(".protocol_name") != -1:
>> +                    protocol_name = get_string_struct(line)
>> +                elif line.find(".bdrv_probe") != -1:
>> +                    probe = True
>> +                elif line.find(".bdrv_probe_device") != -1:
>> +                    probe_device = True
>> +                elif line == "};":
>> +                    add_module(fheader, library, format_name, protocol_name,
>> +                                probe, probe_device)
>> +                    found_start = False
>> +            elif line.find("static BlockDriver") != -1:
>> +                found_something = True
>> +                found_start = True
>> +                format_name = ""
>> +                protocol_name = ""
>> +                probe = False
>> +                probe_device = False
>> +
>> +        if not found_something:
>> +            print("No BlockDriver struct found in " + filename + ". \
>> +                    Is this really a module?", file=sys.stderr)
>> +            sys.exit(1)
>> +
>> +def print_top(fheader):
>> +    fheader.write('''/* AUTOMATICALLY GENERATED, DO NOT MODIFY */
>> +/*
>> + * QEMU Block Module Infrastructure
>> + *
>> + * Copyright Red Hat, Inc. 2015
>> + *
>> + * Authors:
>> + *  Marc Mari       <address@hidden>
> 
> Here!
> 
>> + *
>> + * This work is licensed under the terms of the GNU GPL, version 2.  See
>> + * the COPYING file in the top-level directory.
>> + *
>> + */
>> +
>> +''')
>> +
>> +    fheader.write('''#ifndef QEMU_MODULE_BLOCK_H
>> +#define QEMU_MODULE_BLOCK_H
>> +
>> +#include "qemu-common.h"
>> +
>> +static const struct {
>> +    const char *format_name;
>> +    const char *protocol_name;
>> +    const char *library_name;
>> +    bool has_probe;
>> +    bool has_probe_device;
>> +} block_driver_modules[] = {''')
>> +
>> +def print_bottom(fheader):
>> +    fheader.write('''
>> +};
>> +
>> +#endif
>> +''')
>> +
>> +# First argument: output folder
>> +# All other arguments: modules source files (.c)
>> +output_dir = sys.argv[1]
>> +if not os.path.isdir(output_dir):
>> +    print("Folder " + output_dir + " does not exist", file=sys.stderr)
>> +    sys.exit(1)
>> +
>> +path = output_dir + 'module_block.h'
>> +
>> +with open(path, 'w') as fheader:
>> +    print_top(fheader)
>> +
>> +    for filename in sys.argv[2:]:
>> +        if os.path.isfile(filename):
>> +            process_file(fheader, filename)
>> +        else:
>> +            print("File " + filename + " does not exist.", file=sys.stderr)
>> +            sys.exit(1)
>> +
>> +    print_bottom(fheader)
>> +
>> +sys.exit(0)
>> -- 
>> 2.5.5
>>
>>
> 
Colin