Re: [PATCH 05/13] perf tools: Introduce strtobool() to string.c

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Mon, Nov 16, 2015 at 11:49:36AM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Mon, Nov 16, 2015 at 11:17:18AM -0300, Arnaldo Carvalho de Melo escreveu:
> > Em Mon, Nov 16, 2015 at 12:10:07PM +0000, Wang Nan escreveu:
> > > This patch clones strtobool() from kernel's string.c to perf's string.c,
> > > then add the function entry to tools/perf/util/include/linux/string.h.
> > > 
> > > string.h in perf utils doesn't have #ifdef guard. This patch fixes it.
> > > 
> > > This is preparation for enforcing BPF program configuration, which
> > > would allow config string like 'inlines=yes'.
> > 
> > This is not perf specific at all, we're trying to move stuff out of
> > tools/perf/ so that it becomes generally usable by other tools/ living
> > code, not just perf.
> > 
> > I'll move it to where I think it should be and post as a reply to this
> > message.
> 
> Find it at the bottom, I had to do a prep patch to move memdup() first,
> so that I could move tools/perf/util/include/linux/string.h to
> tools/include/linux/string.h, there is still work to do to fully move
> tools/perf/util/string.c to tools/lib/, will do eventually, for now what
> you need is there.

Also, I'm pushing what I have to the perf/ebpf branch in my tree.

- Arnaldo
 
> - Arnaldo
> 
> commit 939d89c6acc78ee48e8ad83e9565a372b9f3987a
> Author: Wang Nan <wangnan0@huawei.com>
> Date:   Mon Nov 16 11:42:05 2015 -0300
> 
>     tools: Clone the kernel's strtobool function
>     
>     Copying it to tools/lib/string.c, the counterpart to the kernel's
>     lib/string.c.
>     
>     This is preparation for enhancing BPF program configuration, which will
>     allow config string like 'inlines=yes'.
>     
>     Signed-off-by: Wang Nan <wangnan0@huawei.com>
>     Cc: Alexei Starovoitov <ast@kernel.org>
>     Cc: Jonathan Cameron <jic23@cam.ac.uk>
>     Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
>     Cc: Zefan Li <lizefan@huawei.com>
>     Cc: pi3orama@163.com
>     Link: http://lkml.kernel.org/r/1447675815-166222-6-git-send-email-wangnan0@huawei.com
>     [ Copied it to tools/lib/string.c instead, to make it usable by other tools/ ]
>     Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> 
> diff --git a/tools/include/linux/string.h b/tools/include/linux/string.h
> index f3a6db6ad732..2e2f736c039c 100644
> --- a/tools/include/linux/string.h
> +++ b/tools/include/linux/string.h
> @@ -6,4 +6,6 @@
>  
>  void *memdup(const void *src, size_t len);
>  
> +int strtobool(const char *s, bool *res);
> +
>  #endif /* _LINUX_STRING_H_ */
> diff --git a/tools/lib/string.c b/tools/lib/string.c
> index ecfd43a9b24e..065e54f42d8f 100644
> --- a/tools/lib/string.c
> +++ b/tools/lib/string.c
> @@ -1,5 +1,20 @@
> +/*
> + *  linux/tools/lib/string.c
> + *
> + *  Copied from linux/lib/string.c, where it is:
> + *
> + *  Copyright (C) 1991, 1992  Linus Torvalds
> + *
> + *  More specifically, the first copied function was strtobool, which
> + *  was introduced by:
> + *
> + *  d0f1fed29e6e ("Add a strtobool function matching semantics of existing in kernel equivalents")
> + *  Author: Jonathan Cameron <jic23@cam.ac.uk>
> + */
> +
>  #include <stdlib.h>
>  #include <string.h>
> +#include <errno.h>
>  #include <linux/string.h>
>  
>  /**
> @@ -17,3 +32,31 @@ void *memdup(const void *src, size_t len)
>  
>  	return p;
>  }
> +
> +/**
> + * strtobool - convert common user inputs into boolean values
> + * @s: input string
> + * @res: result
> + *
> + * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
> + * Otherwise it will return -EINVAL.  Value pointed to by res is
> + * updated upon finding a match.
> + */
> +int strtobool(const char *s, bool *res)
> +{
> +	switch (s[0]) {
> +	case 'y':
> +	case 'Y':
> +	case '1':
> +		*res = true;
> +		break;
> +	case 'n':
> +	case 'N':
> +	case '0':
> +		*res = false;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +	return 0;
> +}