[lxc-devel] [PATCH 2/6] Delete string from array Add function to delete a string from a non-null terminated buffer

[Serge Hallyn]

Quoting Christian Brauner (christianvanbrauner at gmail.com):

I'm probably wrong, but

1. if the buffer is non-null-terminated, then can't the memmove of
	strlen(del) - needlelen + 1 end up in a segv?
2. the comment should probably mention newlines.  If needle doesn't
	include newline, and the string is a policy, we'll end up
	with extra newlines.  Which may not matter, unless we do
	thousands of operations on a container...

> Signed-off-by: Christian Brauner <christianvanbrauner at gmail.com>
> 
>  100.0% src/lxc/
> diff --git a/src/lxc/utils.c b/src/lxc/utils.c
> index 7ced314..5940542 100644
> --- a/src/lxc/utils.c
> +++ b/src/lxc/utils.c
> @@ -1466,3 +1466,17 @@ err:
>  	close(fd);
>  	return ret;
>  }
> +
> +bool lxc_delete_string_in_array(char *haystack, size_t haystacklen,
> +				const char *needle, size_t needlelen)
> +{
> +	char *del = NULL;
> +	bool bret = false;
> +
> +	if ((del = memmem(haystack, haystacklen, needle, needlelen))) {
> +		memmove(del, del + needlelen, strlen(del) - needlelen + 1);
> +		bret = true;
> +	}
> +	return bret;
> +}
> +
> diff --git a/src/lxc/utils.h b/src/lxc/utils.h
> index ee12dde..715d125 100644
> --- a/src/lxc/utils.h
> +++ b/src/lxc/utils.h
> @@ -243,6 +243,9 @@ extern char *lxc_append_paths(const char *first, const char *second);
>  extern bool lxc_string_in_list(const char *needle, const char *haystack, char sep);
>  extern char **lxc_string_split(const char *string, char sep);
>  extern char **lxc_string_split_and_trim(const char *string, char sep);
> +/* Delete a string from a non-null terminated buffer. */
> +bool lxc_delete_string_in_array(char *haystack, size_t haystacklen,
> +				const char *needle, size_t needlelen);
>  
>  /* some simple array manipulation utilities */
>  typedef void (*lxc_free_fn)(void *);
> -- 
> 2.5.1
>