git: f5a4ae253931 - stable/13 - libiscsiutil: Use open_memstream to build the outgoing block of keys.

The branch stable/13 has been updated by jhb:

URL: https://cgit.FreeBSD.org/src/commit/?id=f5a4ae25393125057b0d287e48da1b6423db1c85

commit f5a4ae25393125057b0d287e48da1b6423db1c85
Author:     John Baldwin <jhb@FreeBSD.org>
AuthorDate: 2021-12-22 18:42:19 +0000
Commit:     John Baldwin <jhb@FreeBSD.org>
CommitDate: 2022-04-29 21:14:37 +0000

    libiscsiutil: Use open_memstream to build the outgoing block of keys.
    
    Reviewed by:    mav
    Sponsored by:   Chelsio Communications
    Differential Revision:  https://reviews.freebsd.org/D33546
    
    (cherry picked from commit 2ccb8fde5eec8a0a25449374fd5a71654460947f)
---
 lib/libiscsiutil/keys.c | 38 +++++++++++++++-----------------------
 1 file changed, 15 insertions(+), 23 deletions(-)

diff --git a/lib/libiscsiutil/keys.c b/lib/libiscsiutil/keys.c
index 8011b0a25329..8c156877a689 100644
--- a/lib/libiscsiutil/keys.c
+++ b/lib/libiscsiutil/keys.c
@@ -102,41 +102,33 @@ keys_load(struct keys *keys, const struct pdu *pdu)
 void
 keys_save(struct keys *keys, struct pdu *pdu)
 {
+	FILE *fp;
 	char *data;
 	size_t len;
 	int i;
 
-	/*
-	 * XXX: Not particularly efficient.
-	 */
-	len = 0;
+	fp = open_memstream(&data, &len);
+	if (fp == NULL)
+		log_err(1, "open_memstream");
 	for (i = 0; i < KEYS_MAX; i++) {
 		if (keys->keys_names[i] == NULL)
 			break;
-		/*
-		 * +1 for '=', +1 for '\0'.
-		 */
-		len += strlen(keys->keys_names[i]) +
-		    strlen(keys->keys_values[i]) + 2;
-	}
 
-	if (len == 0)
-		return;
+		fprintf(fp, "%s=%s", keys->keys_names[i], keys->keys_values[i]);
 
-	data = malloc(len);
-	if (data == NULL)
-		log_err(1, "malloc");
+		/* Append a '\0' after each key pair. */
+		fputc('\0', fp);
+	}
+	if (fclose(fp) != 0)
+		log_err(1, "fclose");
+
+	if (len == 0) {
+		free(data);
+		data = NULL;
+	}
 
 	pdu->pdu_data = data;
 	pdu->pdu_data_len = len;
-
-	for (i = 0; i < KEYS_MAX; i++) {
-		if (keys->keys_names[i] == NULL)
-			break;
-		data += sprintf(data, "%s=%s",
-		    keys->keys_names[i], keys->keys_values[i]);
-		data += 1; /* for '\0'. */
-	}
 }
 
 const char *