From 40e5a5811c6ffce9b0974e93cdd927cbcf60c157 Mon Sep 17 00:00:00 2001
From: Joe Hunkeler <jhunkeler@gmail.com>
Date: Tue, 11 Aug 2015 16:51:37 -0400
Subject: Repatch (from linux) of OSX IRAF

---
 sys/osb/bswap4.f | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 sys/osb/bswap4.f

(limited to 'sys/osb/bswap4.f')

diff --git a/sys/osb/bswap4.f b/sys/osb/bswap4.f
new file mode 100644
index 00000000..1cfa107c
--- /dev/null
+++ b/sys/osb/bswap4.f
@@ -0,0 +1,29 @@
+c BSWAP4 - Move bytes from array "a" to array "b", swapping the four bytes
+c in each successive 4 byte group, i.e., 12345678 becomes 43218765.
+
+	subroutine bswap4 (a, aoff, b, boff, nbytes)
+
+	character*1 a(*), b(*), temp
+	integer	aoff, boff, nbytes, i
+	integer aoff1, boff1, aoff2, boff2, aoff3, boff3
+
+		if (nbytes .le. 4) then
+		    return
+		endif
+
+		aoff1 = aoff + 1
+		boff1 = boff + 1
+		aoff2 = aoff + 2
+		boff2 = boff + 2
+		aoff3 = aoff + 3
+		boff3 = boff + 3
+
+ 		do 10 i = 0, nbytes-3, 4
+		    temp = a(aoff1+i)
+		    b(boff1+i) = a(aoff2+i)
+		    b(boff2+i) = temp
+		    temp = a(aoff3+i)
+		    b(boff3+i) = a(aoff+i)
+		    b(boff+i) = temp
+ 10		continue
+	end
-- 
cgit