From c359ac9128b9b1a6fda29a2a49da0991f835ad0e Mon Sep 17 00:00:00 2001
From: "Wladimir J. van der Laan" <laanwj@gmail.com>
Date: Sun, 7 Aug 2011 16:16:49 +0200
Subject: [PATCH] allow empty/missing amounts in URL

---
 src/qt/guiutil.cpp | 13 +++++++++++--
 src/qt/guiutil.h   |  1 +
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/qt/guiutil.cpp b/src/qt/guiutil.cpp
index 3516d4f8..6329d51d 100644
--- a/src/qt/guiutil.cpp
+++ b/src/qt/guiutil.cpp
@@ -53,9 +53,18 @@ bool GUIUtil::parseBitcoinURL(const QUrl *url, SendCoinsRecipient *out)
     SendCoinsRecipient rv;
     rv.address = url->path();
     rv.label = url->queryItemValue("label");
-    if(!BitcoinUnits::parse(BitcoinUnits::BTC, url->queryItemValue("amount"), &rv.amount))
+
+    QString amount = url->queryItemValue("amount");
+    if(amount.isEmpty())
     {
-        return false;
+        rv.amount = 0;
+    }
+    else // Amount is non-empty
+    {
+        if(!BitcoinUnits::parse(BitcoinUnits::BTC, amount, &rv.amount))
+        {
+            return false;
+        }
     }
     if(out)
     {
diff --git a/src/qt/guiutil.h b/src/qt/guiutil.h
index 012e4975..5f63c16e 100644
--- a/src/qt/guiutil.h
+++ b/src/qt/guiutil.h
@@ -27,6 +27,7 @@ public:
     static void setupAmountWidget(QLineEdit *widget, QWidget *parent);
 
     // Parse "bitcoin:" URL into recipient object, return true on succesful parsing
+    // See Bitcoin URL definition discussion here: https://bitcointalk.org/index.php?topic=33490.0
     static bool parseBitcoinURL(const QUrl *url, SendCoinsRecipient *out);
 };