From 50123e0062a9e32a7b66f5355edb280966b7a61f Mon Sep 17 00:00:00 2001
From: Sebastian Hengst <archaeopteryx@coole-files.de>
Date: Tue, 17 Oct 2017 22:23:30 +0200
Subject: [PATCH] Backed out changeset ef64f4c98cc6 (bug 1409394) for failing
 browser-chrome's browser_save_link-perwindowpb.js and browser_libraryDrop.js
 on OS X and leaks detected by chrome test on Linux x64 asan. r=backout on a
 CLOSED TREE

---
 dom/file/FileReader.cpp | 84 +++++++++++++----------------------------
 1 file changed, 26 insertions(+), 58 deletions(-)

diff --git a/dom/file/FileReader.cpp b/dom/file/FileReader.cpp
index ce963ad4d165..94a06f9cda76 100644
--- a/dom/file/FileReader.cpp
+++ b/dom/file/FileReader.cpp
@@ -264,37 +264,6 @@ FileReader::DoAsyncWait()
   return NS_OK;
 }
 
-namespace {
-
-void
-PopulateBufferForBinaryString(char16_t* aDest, const char* aSource,
-                              uint32_t aCount)
-{
-  const unsigned char* source = (const unsigned char*)aSource;
-  char16_t* end = aDest + aCount;
-  while (aDest != end) {
-    *aDest = *source;
-    ++aDest;
-    ++source;
-  }
-}
-
-nsresult
-ReadFuncBinaryString(nsIInputStream* aInputStream,
-                     void* aClosure,
-                     const char* aFromRawSegment,
-                     uint32_t aToOffset,
-                     uint32_t aCount,
-                     uint32_t* aWriteCount)
-{
-  char16_t* dest = static_cast<char16_t*>(aClosure) + aToOffset;
-  PopulateBufferForBinaryString(dest, aFromRawSegment, aCount);
-  *aWriteCount = aCount;
-  return NS_OK;
-}
-
-} // anonymous
-
 nsresult
 FileReader::DoReadData(uint64_t aCount)
 {
@@ -322,35 +291,34 @@ FileReader::DoReadData(uint64_t aCount)
 
     dest += oldLen;
 
-    if (NS_InputStreamIsBuffered(mAsyncStream)) {
-      nsresult rv = mAsyncStream->ReadSegments(ReadFuncBinaryString, dest,
-                                               aCount, &bytesRead);
-      NS_ENSURE_SUCCESS(rv, rv);
-    } else {
-      while (aCount > 0) {
-        char tmpBuffer[4096];
-        uint32_t minCount =
-          XPCOM_MIN(aCount, static_cast<uint64_t>(sizeof(tmpBuffer)));
-        uint32_t read;
+    while (aCount > 0) {
+      char tmpBuffer[4096];
+      uint32_t minCount =
+        XPCOM_MIN(aCount, static_cast<uint64_t>(sizeof(tmpBuffer)));
+      uint32_t read;
 
-        nsresult rv = mAsyncStream->Read(tmpBuffer, minCount, &read);
-        if (rv == NS_BASE_STREAM_CLOSED) {
-          rv = NS_OK;
-        }
-
-        NS_ENSURE_SUCCESS(rv, rv);
-
-        if (read == 0) {
-          // The stream finished too early.
-          return NS_ERROR_OUT_OF_MEMORY;
-        }
-
-        PopulateBufferForBinaryString(dest, tmpBuffer, read);
-
-        dest += read;
-        aCount -= read;
-        bytesRead += read;
+      nsresult rv = mAsyncStream->Read(tmpBuffer, minCount, &read);
+      if (rv == NS_BASE_STREAM_CLOSED) {
+        rv = NS_OK;
       }
+
+      NS_ENSURE_SUCCESS(rv, rv);
+
+      if (read == 0) {
+        // The stream finished too early.
+        return NS_ERROR_OUT_OF_MEMORY;
+      }
+
+      char16_t* end = dest + read;
+      const unsigned char* source = (const unsigned char*)tmpBuffer;
+      while (dest != end) {
+        *dest = *source;
+        ++dest;
+        ++source;
+      }
+
+      aCount -= read;
+      bytesRead += read;
     }
 
     MOZ_ASSERT(size.value() == oldLen + bytesRead);