From 29d3439900bbf2c4878573166806b8c8ccfd2e14 Mon Sep 17 00:00:00 2001
From: Patrick Pelissier <patrick.pelissier@gmail.com>
Date: Tue, 14 Mar 2017 21:31:47 +0100
Subject: [PATCH] Add SWAP for string

---
 m-string.h           | 13 +++++++++++++
 tests/test-mstring.c |  6 ++++++
 2 files changed, 19 insertions(+)

diff --git a/m-string.h b/m-string.h
index cecfa187..a86bbc3c 100644
--- a/m-string.h
+++ b/m-string.h
@@ -215,6 +215,18 @@ string_init_move(string_t v1, string_t v2)
   STRING_CONTRACT (v1);
 }
 
+static inline void
+string_swap(string_t v1, string_t v2)
+{
+  STRING_CONTRACT (v1);
+  STRING_CONTRACT (v2);
+  M_SWAP (size_t, v1->size, v2->size);
+  M_SWAP (size_t, v1->alloc, v2->alloc);
+  M_SWAP (char *, v1->ptr, v2->ptr);
+  STRING_CONTRACT (v1);
+  STRING_CONTRACT (v2);
+}
+
 static inline void
 string_move(string_t v1, string_t v2)
 {
@@ -677,6 +689,7 @@ string_in_str(string_t v, FILE *f)
 #define STRING_OPLIST                                                   \
   (INIT(string_init),INIT_SET(string_init_set), SET(string_set),        \
    INIT_MOVE(string_init_move), MOVE(string_move),                      \
+   SWAP(string_swap),                                                   \
    CLEAR(string_clear), HASH(string_hash), EQUAL(string_equal_p),       \
    CMP(string_cmp), TYPE(string_t), GET_STR(string_get_str),            \
    OUT_STR(string_out_str), IN_STR(string_in_str),                      \
diff --git a/tests/test-mstring.c b/tests/test-mstring.c
index 1989ad1f..2cf713a7 100644
--- a/tests/test-mstring.c
+++ b/tests/test-mstring.c
@@ -191,6 +191,12 @@ int main(void)
   fclose(f);
   assert (string_equal_p(s1, s2));
 
+  string_set_str(s1, "AZERTY");
+  string_set_str(s2, "QWERTY");
+  string_swap (s1, s2);
+  assert(string_equal_str_p (s1, "QWERTY"));
+  assert(string_equal_str_p (s2, "AZERTY"));
+
   string_clear (s1);
   exit(0);
 }