In a future commit, we'll want the ability to efficiently swap the
contents of two strvec instances without needing to copy any data.
Since a strvec is simply a pointer and two sizes, swapping them is as
simply as copying the two pointers and sizes, so let's do that.
We use a temporary here simply because C doesn't provide a standard
swapping function, unlike C++ and Rust, but a good optimizing compiler
will recognize this syntax and handle it appropriately using an
optimization pass.
Signed-off-by: brian m. carlson <sandals@xxxxxxxxxxxxxxxxxxxx>
---
strvec.c | 7 +++++++
strvec.h | 5 +++++
2 files changed, 12 insertions(+)
diff --git a/strvec.c b/strvec.c
index 178f4f3748..93006f1e63 100644
--- a/strvec.c
+++ b/strvec.c
@@ -106,3 +106,10 @@ const char **strvec_detach(struct strvec *array)
return ret;
}
}
+
+void strvec_swap(struct strvec *a, struct strvec *b)
+{
+ struct strvec t = *a;
+ *a = *b;
+ *b = t;
+}
diff --git a/strvec.h b/strvec.h
index 4715d3e51f..5b762532bb 100644
--- a/strvec.h
+++ b/strvec.h
@@ -88,4 +88,9 @@ void strvec_clear(struct strvec *);
*/
const char **strvec_detach(struct strvec *);
+/**
+ * Swap the contents of two `strvec` structs without allocating.
+ */
+void strvec_swap(struct strvec *, struct strvec *);
+
#endif /* STRVEC_H */
