Re: [PATCH] regex: support non-greedy quantifiers

[Julien Ramseier <j.ramseier@gmail.com>]

> Le 13 mars 2016 à 12:06, Julien Ramseier <j.ramseier@gmail.com> a écrit :
> 
> Here's a tiny patch to enable non-greedy regex quantifiers.
> This is not specified by POSIX, but I think it's a useful
> extension, and all the code for supporting it is already present.
> 
> I tested this against the TRE and AT&T test suites (from NetBSD)
> and didn't found any regressions.
> However I don't know all the ins and outs of the implementation
> and I may have missed something obvious.
> 
> - Julien
> 
> diff --git a/src/regex/regcomp.c b/src/regex/regcomp.c
> index 5fad98b..cc7d633 100644
> --- a/src/regex/regcomp.c
> +++ b/src/regex/regcomp.c
> @@ -979,6 +979,7 @@ static reg_errcode_t tre_parse(tre_parse_ctx_t *ctx)
> 	parse_iter:
> 		for (;;) {
> 			int min, max;
> +			int minimal = 0;
> 
> 			if (*s!='\\' && *s!='*') {
> 				if (!ere)
> @@ -1014,11 +1015,16 @@ static reg_errcode_t tre_parse(tre_parse_ctx_t *ctx)
> 				if (*s == '?')
> 					max = 1;
> 				s++;
> +				/* Non-greedy */
> +				if (ere && *s == '?') {
> +					minimal = 1;
> +					s++;
> +				}
> 			}
> 			if (max == 0)
> 				ctx->n = tre_ast_new_literal(ctx->mem, EMPTY, -1, -1);
> 			else
> -				ctx->n = tre_ast_new_iter(ctx->mem, ctx->n, min, max, 0);
> +				ctx->n = tre_ast_new_iter(ctx->mem, ctx->n, min, max, minimal);
> 			if (!ctx->n)
> 				return REG_ESPACE;
> 		}
> -- 
> 2.7.2

Ping?