[Spice-devel] [spice-common] utils: Add genum -> string helpers

[Frediano Ziglio]

> 
> This makes it easier to convert enums registered with glib type system
> to string in order to print them at runtime.
> 
> Signed-off-by: Christophe Fergeau <cfergeau at redhat.com>
> ---
>  common/Makefile.am |  2 ++
>  common/meson.build |  2 ++
>  common/utils.c     | 64 ++++++++++++++++++++++++++++++++++++++++++++++
>  common/utils.h     | 33 ++++++++++++++++++++++++
>  4 files changed, 101 insertions(+)
>  create mode 100644 common/utils.c
>  create mode 100644 common/utils.h
> 
> diff --git a/common/Makefile.am b/common/Makefile.am
> index da0d941..197e419 100644
> --- a/common/Makefile.am
> +++ b/common/Makefile.am
> @@ -50,6 +50,8 @@ libspice_common_la_SOURCES =		\
>  	rop3.h				\
>  	snd_codec.c			\
>  	snd_codec.h			\
> +	utils.c				\
> +	utils.h				\
>  	verify.h			\
>  	$(NULL)
>  
> diff --git a/common/meson.build b/common/meson.build
> index 6ac55dc..8f22310 100644
> --- a/common/meson.build
> +++ b/common/meson.build
> @@ -35,6 +35,8 @@ spice_common_sources = [
>    'rop3.h',
>    'snd_codec.c',
>    'snd_codec.h',
> +  'utils.c',
> +  'utils.h',
>    'verify.h'
>  ]
>  
> diff --git a/common/utils.c b/common/utils.c
> new file mode 100644
> index 0000000..768eeac
> --- /dev/null
> +++ b/common/utils.c
> @@ -0,0 +1,64 @@
> +/* -*- Mode: C; c-basic-offset: 4; indent-tabs-mode: nil -*- */

Really OT: somebody uses these?

> +/*
> +   Copyright (C) 2010, 2011, 2018 Red Hat, Inc.
> +
> +   This library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   This library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with this library; if not, see
> <http://www.gnu.org/licenses/>.
> +*/
> +

I don't know if it is just SPICE server, don't we require to include config.h
in all .c files?

> +#include "utils.h"
> +
> +/* These 2 functions come from
> + * libvirt-glib/libvirt-gconfig/libvirt-gconfig-helpers.c
> + * Copyright (C) 2010, 2011 Red Hat, Inc.
> + * LGPLv2.1+ licensed */
> +
> +const char *
> +spice_genum_get_nick(GType enum_type, gint value)
> +{
> +    GEnumClass *enum_class;
> +    GEnumValue *enum_value;
> +
> +    g_return_val_if_fail(G_TYPE_IS_ENUM(enum_type), NULL);
> +
> +    enum_class = g_type_class_ref(enum_type);
> +    enum_value = g_enum_get_value(enum_class, value);
> +    g_type_class_unref(enum_class);
> +
> +    if (enum_value != NULL) {
> +        return enum_value->value_nick;
> +    }
> +
> +    g_return_val_if_reached(NULL);
> +}
> +
> +int
> +spice_genum_get_value(GType enum_type, const char *nick,
> +                      gint default_value)
> +{
> +    GEnumClass *enum_class;
> +    GEnumValue *enum_value;
> +
> +    g_return_val_if_fail(G_TYPE_IS_ENUM(enum_type), default_value);
> +    g_return_val_if_fail(nick != NULL, default_value);
> +
> +    enum_class = g_type_class_ref(enum_type);
> +    enum_value = g_enum_get_value_by_nick(enum_class, nick);
> +    g_type_class_unref(enum_class);
> +
> +    if (enum_value != NULL) {
> +        return enum_value->value;
> +    }
> +
> +    g_return_val_if_reached(default_value);
> +}
> diff --git a/common/utils.h b/common/utils.h
> new file mode 100644
> index 0000000..395f102
> --- /dev/null
> +++ b/common/utils.h
> @@ -0,0 +1,33 @@
> +/* -*- Mode: C; c-basic-offset: 4; indent-tabs-mode: nil -*- */
> +/*
> +   Copyright (C) 2010, 2011, 2018 Red Hat, Inc.
> +
> +   This library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   This library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with this library; if not, see
> <http://www.gnu.org/licenses/>.
> +*/
> +
> +#ifndef __UTILS_H
> +#define __UTILS_H
> +

I don't really like much identifier reserved by C99 to be used.
It seems that most of spice-common uses _H_SPICE_ prefix (which is
actually reserved too). H_SPICE_UTILS_whatever sounds reasonable.

I didn't like much MS "fashion" of embed GUID in the guard names
but at the end was a valid solution...

#ifndef H_SPICE_clAxMndkWXNHnJvCn8nFfx

:-) (well, an embedded base-62 version of a GUID) ??

More seriously SPICE_COMMON_UTILS_H ?

> +#include <glib.h>
> +#include <glib-object.h>
> +
> +G_BEGIN_DECLS
> +
> +const char *spice_genum_get_nick(GType enum_type, gint value);
> +int spice_genum_get_value(GType enum_type, const char *nick,
> +                          gint default_value);
> +
> +G_END_DECLS
> +
> +#endif //__UTILS_H

Otherwise is fine.

Frediano