1 files changed, 17 insertions, 0 deletions
diff --git a/src/libstddjb/stralloc_reverse_blocks.c b/src/libstddjb/stralloc_reverse_blocks.c
new file mode 100644
index 0000000..6a2e4b8
--- /dev/null
+++ b/src/libstddjb/stralloc_reverse_blocks.c
@@ -0,0 +1,17 @@
+/* ISC license. */
+
+#include <skalibs/bytestr.h>
+#include <skalibs/stralloc.h>
+
+void stralloc_reverse_blocks (stralloc *sa, unsigned int size)
+{
+  register unsigned int n = sa->len / (size << 1) ;
+  register unsigned int i = 0 ;
+  char tmp[size] ;
+  for (; i < n ; i++)
+  {
+    byte_copy(tmp, size, sa->s + i * size) ;
+    byte_copy(sa->s + i * size, size, sa->s + (2*n - 1 - i) * size) ;
+    byte_copy(sa->s + (2*n - 1 - i) * size, size, tmp) ;
+  }
+}