New internal archive_string_concat utility function.

2 files changed, 18 insertions, 0 deletions

diff --git a/lib/libarchive/archive_string.c b/lib/libarchive/archive_string.c
index d06b72a..fc6a344 100644
--- a/lib/libarchive/archive_string.c
+++ b/lib/libarchive/archive_string.c
@@ -70,6 +70,18 @@ __archive_string_copy(struct archive_string *dest, struct archive_string *src)
 }
 
 void
+__archive_string_concat(struct archive_string *dest, struct archive_string *src)
+{
+	if (src->length > 0) {
+		if (__archive_string_ensure(dest, dest->length + src->length + 1) == NULL)
+			__archive_errx(1, "Out of memory");
+		memcpy(dest->s + dest->length, src->s, src->length);
+		dest->length += src->length;
+		dest->s[dest->length] = 0;
+	}
+}
+
+void
 __archive_string_free(struct archive_string *as)
 {
 	as->length = 0;
diff --git a/lib/libarchive/archive_string.h b/lib/libarchive/archive_string.h
index 819be75..73e527d 100644
--- a/lib/libarchive/archive_string.h
+++ b/lib/libarchive/archive_string.h
@@ -92,6 +92,12 @@ __archive_string_copy(struct archive_string *dest, struct archive_string *src);
 #define archive_string_copy(dest, src) \
 	__archive_string_copy(dest, src)
 
+/* Concatenate one archive_string to another */
+void
+__archive_string_concat(struct archive_string *dest, struct archive_string *src);
+#define archive_string_concat(dest, src) \
+	__archive_string_concat(dest, src)
+
 /* Ensure that the underlying buffer is at least as large as the request. */
 struct archive_string *
 __archive_string_ensure(struct archive_string *, size_t);