[PATCH v3 1/4] scripts: include: Add string_util.h for strsep_unescaped

[Marco Felsch]

On 26-03-16, Jonas Rebmann wrote:
> lib/string.c has strsep_unescaped() that will be useful for the keytoc
> host tool to split ENV specs at spaces not preceded by a backslash in a
> future commit.
> 
> In preparation, create scripts/include/string_util.h with a copy of that
> function as to have it available in host tools.
> 
> Signed-off-by: Jonas Rebmann <jre at pengutronix.de>
> ---
>  scripts/include/string_util.h | 65 +++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 65 insertions(+)
> 
> diff --git a/scripts/include/string_util.h b/scripts/include/string_util.h
> new file mode 100644
> index 0000000000..e71aa60d26
> --- /dev/null
> +++ b/scripts/include/string_util.h
> @@ -0,0 +1,65 @@
> +#ifndef _TOOLS_STRING_UTIL_H_
> +#define _TOOLS_STRING_UTIL_H_
> +
> +#include <linux/types.h>
> +#include <stddef.h>
> +
> +// SPDX-SnippetBegin
> +// SPDX-Snippet-Comment: Origin-URL: https://git.pengutronix.de/cgit/barebox/tree/lib/string.c?id=dfcf686f94a5a5387660f2afab79a714baab828a

Do we really need this if we reference code within our own repo?

> +/**
> + * strsep_unescaped - Split a string into tokens, while ignoring escaped delimiters
> + * @s: The string to be searched
> + * @ct: The delimiter characters to search for
> + * @delim: optional pointer to store found delimiter into
> + *
> + * strsep_unescaped() behaves like strsep unless it meets an escaped delimiter.
> + * In that case, it shifts the string back in memory to overwrite the escape's
> + * backslash then continues the search until an unescaped delimiter is found.
> + *
> + * On end of string, this function returns NULL. As long as a non-NULL
> + * value is returned and @delim is not NULL, the found delimiter will
> + * be stored into *@delim.
> + */
> +static char *strsep_unescaped(char **s, const char *ct, char *delim)

Is there a reason for defining this function within a .h instead of a .c
file?

Regards,
  Marco

> +{
> +	char *sbegin = *s, *hay;
> +	const char *needle;
> +	size_t shift = 0;
> +
> +	if (sbegin == NULL)
> +		return NULL;
> +
> +	for (hay = sbegin; *hay != '\0'; ++hay) {
> +		*hay = hay[shift];
> +
> +		if (*hay == '\\') {
> +			*hay = hay[++shift];
> +			if (*hay != '\\')
> +				continue;
> +		}
> +
> +		for (needle = ct; *needle != '\0'; ++needle) {
> +			if (*hay == *needle)
> +				goto match;
> +		}
> +	}
> +
> +	*s = NULL;
> +	if (delim)
> +		*delim = '\0';
> +	return sbegin;
> +
> +match:
> +	if (delim)
> +		*delim = *hay;
> +	*hay = '\0';
> +	*s = &hay[shift + 1];
> +
> +	return sbegin;
> +}
> +
> +// SPDX-SnippetEnd
> +
> +
> +#endif /* _TOOLS_STRING_UTIL_H_ */
> 
> -- 
> 2.53.0.308.g50d063e335
> 
> 
> 

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