When trying to print a very long email on iOS, the print preview is blank

https://bugs.webkit.org/show_bug.cgi?id=187077
<rdar://problem/41107013>

Reviewed by Timothy Hatcher.

* UIProcess/ios/WebPageProxyIOS.mm:
(WebKit::WebPageProxy::computePagesForPrintingAndDrawToPDF):
ChildProcessProxy::sendSync has a (surprising) default timeout of 1 second,
(as opposed to Connection::sendSync's default timeout of ∞ seconds).
The printing path already waits ∞ seconds for the final PDF, but currently
uses the default 1 second timeout for page count computation. If page
count computation takes more than 1 second, the preview will be blank.
Since the print preview is generated asynchronously, we really want
to wait until it's done, and not give up after 1 second.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@233250 268f45cc-cd09-0410-ab3c-d52691b4dbfc

diff --git a/Source/WebKit/ChangeLog b/Source/WebKit/ChangeLog
index ee3b414..dfd8848 100644 (file)
--- a/Source/WebKit/ChangeLog
+++ b/Source/WebKit/ChangeLog
@@ -1,3 +1,21 @@
+2018-06-27  Tim Horton  <timothy_horton@apple.com>
+
+        When trying to print a very long email on iOS, the print preview is blank
+        https://bugs.webkit.org/show_bug.cgi?id=187077
+        <rdar://problem/41107013>
+
+        Reviewed by Timothy Hatcher.
+
+        * UIProcess/ios/WebPageProxyIOS.mm:
+        (WebKit::WebPageProxy::computePagesForPrintingAndDrawToPDF):
+        ChildProcessProxy::sendSync has a (surprising) default timeout of 1 second,
+        (as opposed to Connection::sendSync's default timeout of ∞ seconds).
+        The printing path already waits ∞ seconds for the final PDF, but currently
+        uses the default 1 second timeout for page count computation. If page
+        count computation takes more than 1 second, the preview will be blank.
+        Since the print preview is generated asynchronously, we really want
+        to wait until it's done, and not give up after 1 second.
+
 2018-06-26  Wenson Hsieh  <wenson_hsieh@apple.com>
 
         [iPad apps on macOS] Unable to interact with video elements that have started playing

diff --git a/Source/WebKit/UIProcess/ios/WebPageProxyIOS.mm b/Source/WebKit/UIProcess/ios/WebPageProxyIOS.mm
index f31515c..7a704c1 100644 (file)
--- a/Source/WebKit/UIProcess/ios/WebPageProxyIOS.mm
+++ b/Source/WebKit/UIProcess/ios/WebPageProxyIOS.mm
@@ -1028,7 +1028,7 @@ uint32_t WebPageProxy::computePagesForPrintingAndDrawToPDF(uint64_t frameID, con
     uint32_t pageCount = 0;
     auto callbackID = m_callbacks.put(WTFMove(callback), m_process->throttler().backgroundActivityToken());
     using Message = Messages::WebPage::ComputePagesForPrintingAndDrawToPDF;
-    process().sendSync(Message(frameID, printInfo, callbackID), Message::Reply(pageCount), m_pageID);
+    process().sendSync(Message(frameID, printInfo, callbackID), Message::Reply(pageCount), m_pageID, Seconds::infinity());
     return pageCount;
 }