From 78a4e462d5538490e8f24cf9d9b083bb043c9cab Mon Sep 17 00:00:00 2001
From: Andrew Johnson <anj@aps.anl.gov>
Date: Mon, 2 Dec 2013 11:12:19 -0600
Subject: [PATCH] libCom: Recognize hex literals in epicsStrtod()

Allows Windows and VxWorks to accept hex integers as a double.
---
 documentation/RELEASE_NOTES.html | 8 ++++++++
 src/libCom/misc/epicsStdlib.c    | 6 ++++++
 2 files changed, 14 insertions(+)

diff --git a/documentation/RELEASE_NOTES.html b/documentation/RELEASE_NOTES.html
index cdbca97cf..0b5b01f4e 100644
--- a/documentation/RELEASE_NOTES.html
+++ b/documentation/RELEASE_NOTES.html
@@ -13,6 +13,14 @@
 
 <!-- Insert new items immediately below here ... -->
 
+<h3>Hex literal support in epicStrtod()</h3>
+
+<p>Some OS implementations of the standard C library routine strtod() do not
+recognize hexadecimal integers, in particular the libraries provided on Windows
+and VxWorks. The internal implementation of epicsStrtod() that these targets use
+now recognizes the 0x prefix and will convert hex numbers correctly. Thanks to
+Dirk Zimoch for suggesting this change.</p>
+
 <h3>Added support for 64-bit Cygwin and MinGW targets</h3>
 
 <p>Both windows-x64-mingw and cygwin-x86_64 build targets are now provided.</p>
diff --git a/src/libCom/misc/epicsStdlib.c b/src/libCom/misc/epicsStdlib.c
index 494fc60be..f1c89aaa3 100644
--- a/src/libCom/misc/epicsStdlib.c
+++ b/src/libCom/misc/epicsStdlib.c
@@ -60,6 +60,12 @@ epicsShareFunc double epicsStrtod(const char *str, char **endp)
         cp++;
     }
 
+    if (epicsStrnCaseCmp("0x", cp, 2) == 0) {
+        if (negative)
+            return strtol(str, endp, 16);
+        else
+            return strtoul(str, endp, 16);
+    }
     if (!isalpha((int)*cp))
         return strtod(str, endp);