From 86f0bdf1ee4661d1b66638c18d8cffad8173460a Mon Sep 17 00:00:00 2001
From: Guillem Jover <guillem@debian.org>
Date: Thu, 22 Jun 2023 02:27:14 +0200
Subject: [PATCH] libdpkg: Add varbuf_add_varbuf() function

---
 lib/dpkg/libdpkg.map  |  1 +
 lib/dpkg/t/t-varbuf.c | 28 +++++++++++++++++++++++++++-
 lib/dpkg/varbuf.c     |  8 ++++++++
 lib/dpkg/varbuf.h     |  1 +
 4 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/lib/dpkg/libdpkg.map b/lib/dpkg/libdpkg.map
index 75918e903..d874a142d 100644
--- a/lib/dpkg/libdpkg.map
+++ b/lib/dpkg/libdpkg.map
@@ -114,6 +114,7 @@ LIBDPKG_PRIVATE {
 	varbuf_reset;
 	varbuf_grow;
 	varbuf_trunc;
+	varbuf_add_varbuf;
 	varbuf_add_char;
 	varbuf_dup_char;
 	varbuf_map_char;
diff --git a/lib/dpkg/t/t-varbuf.c b/lib/dpkg/t/t-varbuf.c
index ee1fdbced..da9dd9a9f 100644
--- a/lib/dpkg/t/t-varbuf.c
+++ b/lib/dpkg/t/t-varbuf.c
@@ -155,6 +155,31 @@ test_varbuf_trunc(void)
 }
 
 static void
+test_varbuf_add_varbuf(void)
+{
+	struct varbuf vb, cb;
+
+	varbuf_init(&vb, 5);
+	varbuf_init(&cb, 0);
+
+	varbuf_add_str(&vb, "1234567890");
+	varbuf_add_varbuf(&cb, &vb);
+	test_pass(cb.used == 10);
+	test_pass(cb.size >= cb.used);
+	test_mem(cb.buf, ==, "1234567890", 10);
+
+	varbuf_reset(&vb);
+	varbuf_add_str(&vb, "abcde");
+	varbuf_add_varbuf(&cb, &vb);
+	test_pass(cb.used == 15);
+	test_pass(cb.size >= cb.used);
+	test_mem(cb.buf, ==, "1234567890abcde", 15);
+
+	varbuf_destroy(&cb);
+	varbuf_destroy(&vb);
+}
+
+static void
 test_varbuf_add_buf(void)
 {
 	struct varbuf vb;
@@ -452,13 +477,14 @@ test_varbuf_detach(void)
 
 TEST_ENTRY(test)
 {
-	test_plan(152);
+	test_plan(158);
 
 	test_varbuf_init();
 	test_varbuf_prealloc();
 	test_varbuf_new();
 	test_varbuf_grow();
 	test_varbuf_trunc();
+	test_varbuf_add_varbuf();
 	test_varbuf_add_buf();
 	test_varbuf_add_char();
 	test_varbuf_dup_char();
diff --git a/lib/dpkg/varbuf.c b/lib/dpkg/varbuf.c
index b605c1c4e..47636d793 100644
--- a/lib/dpkg/varbuf.c
+++ b/lib/dpkg/varbuf.c
@@ -100,6 +100,14 @@ varbuf_get_str(struct varbuf *v)
 }
 
 void
+varbuf_add_varbuf(struct varbuf *v, const struct varbuf *other)
+{
+	varbuf_grow(v, other->used);
+	memcpy(v->buf + v->used, other->buf, other->used);
+	v->used += other->used;
+}
+
+void
 varbuf_add_char(struct varbuf *v, int c)
 {
 	varbuf_grow(v, 1);
diff --git a/lib/dpkg/varbuf.h b/lib/dpkg/varbuf.h
index c5c9458e8..9b10bdc8b 100644
--- a/lib/dpkg/varbuf.h
+++ b/lib/dpkg/varbuf.h
@@ -83,6 +83,7 @@ void varbuf_reset(struct varbuf *v);
 void varbuf_destroy(struct varbuf *v);
 void varbuf_free(struct varbuf *v);
 
+void varbuf_add_varbuf(struct varbuf *v, const struct varbuf *other);
 void varbuf_add_char(struct varbuf *v, int c);
 void varbuf_dup_char(struct varbuf *v, int c, size_t n);
 void varbuf_map_char(struct varbuf *v, int c_src, int c_dst);
-- 
2.11.4.GIT