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Re: [PATCH] parse-options: use COPY_ARRAY in parse_options_concat()

From
MÅMartin Ågren <martin.agren@gmail.com>
Date
Nov 13, 2019, 18:25 UTC
Message-ID
<20191113182548.1707-1-martin.agren@gmail.com>
In-Reply-To
<df941c25-22ea-3523-9607-8e892dea320c@web.de>
On Wed, 13 Nov 2019 at 18:19, René Scharfe <l.s.r@web.de> wrote:
Show 8 quoted lines
>         ALLOC_ARRAY(ret, st_add3(a_len, b_len, 1));
> -       for (i = 0; i < a_len; i++)
> -               ret[i] = a[i];
> -       for (i = 0; i < b_len; i++)
> -               ret[a_len + i] = b[i];
> +       COPY_ARRAY(ret, a, a_len);
> +       COPY_ARRAY(ret + a_len, b, b_len);
>         ret[a_len + b_len] = b[b_len]; /* final OPTION_END */

Maybe include that last one in the COPY_ARRAY with something like this on top?

-       COPY_ARRAY(ret + a_len, b, b_len);
-       ret[a_len + b_len] = b[b_len]; /* final OPTION_END */
+       /* 1 more to include the final OPTION_END */
+       COPY_ARRAY(ret + a_len, b, st_add(b_len, 1));
Or maybe even something like the below (directly on top of your patch)?

(Plus, you could drop `i` entirely, but I'm not sure that's worth golfing on.)

Martin
diff --git a/parse-options-cb.c b/parse-options-cb.c
index 2bde78b726..11196cfb96 100644
--- a/parse-options-cb.c
+++ b/parse-options-cb.c
@@ -185,11 +185,11 @@ struct option *parse_options_concat(struct option *a, struct option *b)
 		a_len++;
 	for (i = 0; b[i].type != OPTION_END; i++)
 		b_len++;
+	b_len++; /* final OPTION_END */
 
-	ALLOC_ARRAY(ret, st_add3(a_len, b_len, 1));
+	ALLOC_ARRAY(ret, st_add(a_len, b_len));
 	COPY_ARRAY(ret, a, a_len);
 	COPY_ARRAY(ret + a_len, b, b_len);
-	ret[a_len + b_len] = b[b_len]; /* final OPTION_END */
 
 	return ret;
 }
-- 
2.24.0
Previous: René ScharfeNext: René Scharfe
Message 4 of 5 in “parse-options: avoid arithmetic on pointer that's potentially NULL”
  1. René ScharfeNov 12, 2019
  2. Junio C HamanoNov 13, 2019
  3. René ScharfeNov 13, 2019
  4. Martin ÅgrenNov 13, 2019
  5. René ScharfeNov 14, 2019

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