Re: [PATCH] glob: implement GLOB_NOMAGIC

[Rich Felker <dalias@libc.org>]

On Sat, Jul 27, 2019 at 01:48:47AM +0200, Ismael Luceno wrote:
> Signed-off-by: Ismael Luceno <ismael@iodev.co.uk>
> ---
>  include/glob.h   |  1 +
>  src/regex/glob.c | 13 +++++++++----
>  2 files changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/include/glob.h b/include/glob.h
> index 4a562a206d52..0ff70bdfeef2 100644
> --- a/include/glob.h
> +++ b/include/glob.h
> @@ -31,6 +31,7 @@ void globfree(glob_t *);
>  #define GLOB_NOESCAPE 0x40
>  #define	GLOB_PERIOD   0x80
>  
> +#define GLOB_NOMAGIC     0x0800
>  #define GLOB_TILDE       0x1000
>  #define GLOB_TILDE_CHECK 0x4000
>  
> diff --git a/src/regex/glob.c b/src/regex/glob.c
> index 58248675c203..0ccd9759c5e7 100644
> --- a/src/regex/glob.c
> +++ b/src/regex/glob.c
> @@ -253,13 +253,18 @@ int glob(const char *restrict pat, int flags, int (*errfunc)(const char *path, i
>  	
>  	for (cnt=0, tail=head.next; tail; tail=tail->next, cnt++);
>  	if (!cnt) {
> +		size_t len;
>  		if (flags & GLOB_NOCHECK) {
> -			tail = &head;
> -			if (append(&tail, pat, strlen(pat), 0))
> -				return GLOB_NOSPACE;
> -			cnt++;
> +			len = strlen(pat);
> +		} else if (flags & GLOB_NOMAGIC) {
> +			len = strcspn(pat, "*?[");
> +			if (pat[len]) return GLOB_NOMATCH;
>  		} else
>  			return GLOB_NOMATCH;
> +		tail = &head;
> +		if (append(&tail, pat, len, 0))
> +			return GLOB_NOSPACE;
> +		cnt++;
>  	}
>  
>  	if (flags & GLOB_APPEND) {

The documentation for this flag is really poor. Do you know how it's
supposed to interact with escaped characters? Is it really supposed to
refuse to expand to the literal pattern when the literal pattern
contains an escaped *, ?, or [ but not a special one?

Otherwise I think this looks ok. Nice use of strcspn.

Rich