1 files changed, 57 insertions, 0 deletions
diff --git a/sys/mwcs/mwswattrs.x b/sys/mwcs/mwswattrs.x
new file mode 100644
index 00000000..14fc72bd
--- /dev/null
+++ b/sys/mwcs/mwswattrs.x
@@ -0,0 +1,57 @@
+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include	<syserr.h>
+include	"mwcs.h"
+
+# MW_SWATTRS -- Set the string value of the named WCS attribute for axis N.
+# The attribute is created if not already defined.  If axis N=0 is specified,
+# the attribute pertains to the entire WCS, not just one axis.
+
+procedure mw_swattrs (mw, axis, attribute, valstr)
+
+pointer	mw			#I pointer to MWCS descriptor
+int	axis			#I axis to which attribute belongs
+char	attribute[ARB]		#I attribute name
+char	valstr[ARB]		#I attribute value
+
+pointer	wp, ap
+int	atno, i
+bool	streq()
+int	mw_refstr()
+errchk	syserrs, mw_refstr
+
+begin
+	# Get current WCS.
+	wp = MI_WCS(mw)
+	if (wp == NULL)
+	    call syserrs (SYS_MWNOWCS, "mw_swattrs")
+
+	# Lookup the named attribute and replace the pointer to the value
+	# string if found.  Otherwise, add a new attribute.
+
+	atno = 0
+	do i = 1, WCS_NWATTR(wp) {
+	    ap = WCS_WATTR(wp,i)
+	    if (AT_AXIS(ap) == axis)
+		if (streq (S(mw,AT_NAME(ap)), attribute)) {
+		    atno = i
+		    break
+		}
+	}
+
+	# Add a new attribute?
+	if (atno == 0) {
+	    atno = WCS_NWATTR(wp) + 1
+	    if (atno > MAX_WATTR)
+		call syserrs (SYS_MWATOVFL, attribute)
+	    else {
+		WCS_NWATTR(wp) = atno
+		ap = WCS_WATTR(wp,atno)
+		AT_AXIS(ap) = axis
+		AT_NAME(ap) = mw_refstr (mw, attribute)
+	    }
+	}
+
+	# Store the value string.
+	AT_VALUE(ap) = mw_refstr (mw, valstr)
+end