diff -r 000000000000 -r 6474c204b198 xpcom/io/Base64.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xpcom/io/Base64.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,350 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "Base64.h"
+
+#include "nsIInputStream.h"
+#include "nsString.h"
+
+#include "plbase64.h"
+
+namespace {
+
+// BEGIN base64 encode code copied and modified from NSPR
+const unsigned char *base = (unsigned char *)"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+template <typename T>
+static void
+Encode3to4(const unsigned char *src, T *dest)
+{
+    uint32_t b32 = (uint32_t)0;
+    int i, j = 18;
+
+    for( i = 0; i < 3; i++ )
+    {
+        b32 <<= 8;
+        b32 |= (uint32_t)src[i];
+    }
+
+    for( i = 0; i < 4; i++ )
+    {
+        dest[i] = base[ (uint32_t)((b32>>j) & 0x3F) ];
+        j -= 6;
+    }
+}
+
+template <typename T>
+static void
+Encode2to4(const unsigned char *src, T *dest)
+{
+    dest[0] = base[ (uint32_t)((src[0]>>2) & 0x3F) ];
+    dest[1] = base[ (uint32_t)(((src[0] & 0x03) << 4) | ((src[1] >> 4) & 0x0F)) ];
+    dest[2] = base[ (uint32_t)((src[1] & 0x0F) << 2) ];
+    dest[3] = (unsigned char)'=';
+}
+
+template <typename T>
+static void
+Encode1to4(const unsigned char *src, T *dest)
+{
+    dest[0] = base[ (uint32_t)((src[0]>>2) & 0x3F) ];
+    dest[1] = base[ (uint32_t)((src[0] & 0x03) << 4) ];
+    dest[2] = (unsigned char)'=';
+    dest[3] = (unsigned char)'=';
+}
+
+template <typename T>
+static void
+Encode(const unsigned char *src, uint32_t srclen, T *dest)
+{
+    while( srclen >= 3 )
+    {
+        Encode3to4(src, dest);
+        src += 3;
+        dest += 4;
+        srclen -= 3;
+    }
+
+    switch( srclen )
+    {
+        case 2:
+            Encode2to4(src, dest);
+            break;
+        case 1:
+            Encode1to4(src, dest);
+            break;
+        case 0:
+            break;
+        default:
+            NS_NOTREACHED("coding error");
+    }
+}
+
+// END base64 encode code copied and modified from NSPR.
+
+template <typename T>
+struct EncodeInputStream_State {
+  unsigned char c[3];
+  uint8_t charsOnStack;
+  typename T::char_type* buffer;
+};
+
+template <typename T>
+NS_METHOD
+EncodeInputStream_Encoder(nsIInputStream *aStream,
+                          void *aClosure,
+                          const char *aFromSegment,
+                          uint32_t aToOffset,
+                          uint32_t aCount,
+                          uint32_t *aWriteCount)
+{
+  NS_ASSERTION(aCount > 0, "Er, what?");
+
+  EncodeInputStream_State<T>* state =
+    static_cast<EncodeInputStream_State<T>*>(aClosure);
+
+  // If we have any data left from last time, encode it now.
+  uint32_t countRemaining = aCount;
+  const unsigned char *src = (const unsigned char*)aFromSegment;
+  if (state->charsOnStack) {
+    unsigned char firstSet[4];
+    if (state->charsOnStack == 1) {
+      firstSet[0] = state->c[0];
+      firstSet[1] = src[0];
+      firstSet[2] = (countRemaining > 1) ? src[1] : '\0';
+      firstSet[3] = '\0';
+    } else /* state->charsOnStack == 2 */ {
+      firstSet[0] = state->c[0];
+      firstSet[1] = state->c[1];
+      firstSet[2] = src[0];
+      firstSet[3] = '\0';
+    }
+    Encode(firstSet, 3, state->buffer);
+    state->buffer += 4;
+    countRemaining -= (3 - state->charsOnStack);
+    src += (3 - state->charsOnStack);
+    state->charsOnStack = 0;
+  }
+
+  // Encode the bulk of the 
+  uint32_t encodeLength = countRemaining - countRemaining % 3;
+  NS_ABORT_IF_FALSE(encodeLength % 3 == 0,
+                    "Should have an exact number of triplets!");
+  Encode(src, encodeLength, state->buffer);
+  state->buffer += (encodeLength / 3) * 4;
+  src += encodeLength;
+  countRemaining -= encodeLength;
+
+  // We must consume all data, so if there's some data left stash it
+  *aWriteCount = aCount;
+
+  if (countRemaining) {
+    // We should never have a full triplet left at this point.
+    NS_ABORT_IF_FALSE(countRemaining < 3, "We should have encoded more!");
+    state->c[0] = src[0];
+    state->c[1] = (countRemaining == 2) ? src[1] : '\0';
+    state->charsOnStack = countRemaining;
+  }
+
+  return NS_OK;
+}
+
+template <typename T>
+nsresult
+EncodeInputStream(nsIInputStream *aInputStream, 
+                  T &aDest,
+                  uint32_t aCount,
+                  uint32_t aOffset)
+{
+  nsresult rv;
+  uint64_t count64 = aCount;
+
+  if (!aCount) {
+    rv = aInputStream->Available(&count64);
+    if (NS_WARN_IF(NS_FAILED(rv)))
+      return rv;
+    // if count64 is over 4GB, it will be failed at the below condition,
+    // then will return NS_ERROR_OUT_OF_MEMORY
+    aCount = (uint32_t)count64;
+  }
+
+  uint64_t countlong =
+    (count64 + 2) / 3 * 4; // +2 due to integer math.
+  if (countlong + aOffset > UINT32_MAX)
+    return NS_ERROR_OUT_OF_MEMORY;
+
+  uint32_t count = uint32_t(countlong);
+
+  aDest.SetLength(count + aOffset);
+  if (aDest.Length() != count + aOffset)
+    return NS_ERROR_OUT_OF_MEMORY;
+
+  EncodeInputStream_State<T> state;
+  state.charsOnStack = 0;
+  state.c[2] = '\0';
+  state.buffer = aOffset + aDest.BeginWriting();
+
+  while (1) {
+    uint32_t read = 0;
+
+    rv = aInputStream->ReadSegments(&EncodeInputStream_Encoder<T>,
+                                    (void*)&state,
+                                    aCount,
+                                    &read);
+    if (NS_FAILED(rv)) {
+      if (rv == NS_BASE_STREAM_WOULD_BLOCK)
+        NS_RUNTIMEABORT("Not implemented for async streams!");
+      if (rv == NS_ERROR_NOT_IMPLEMENTED)
+        NS_RUNTIMEABORT("Requires a stream that implements ReadSegments!");
+      return rv;
+    }
+
+    if (!read)
+      break;
+  }
+
+  // Finish encoding if anything is left
+  if (state.charsOnStack)
+    Encode(state.c, state.charsOnStack, state.buffer);
+
+  if (aDest.Length())
+    // May belong to an nsCString with an unallocated buffer, so only null
+    // terminate if there is a need to.
+    *aDest.EndWriting() = '\0';
+
+  return NS_OK;
+}
+
+} // namespace (anonymous)
+
+namespace mozilla {
+
+nsresult
+Base64EncodeInputStream(nsIInputStream *aInputStream, 
+                        nsACString &aDest,
+                        uint32_t aCount,
+                        uint32_t aOffset)
+{
+  return EncodeInputStream<nsACString>(aInputStream, aDest, aCount, aOffset);
+}
+
+nsresult
+Base64EncodeInputStream(nsIInputStream *aInputStream, 
+                        nsAString &aDest,
+                        uint32_t aCount,
+                        uint32_t aOffset)
+{
+  return EncodeInputStream<nsAString>(aInputStream, aDest, aCount, aOffset);
+}
+
+nsresult
+Base64Encode(const nsACString &aBinaryData, nsACString &aString)
+{
+  // Check for overflow.
+  if (aBinaryData.Length() > (UINT32_MAX / 4) * 3) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // Don't ask PR_Base64Encode to encode empty strings
+  if (aBinaryData.IsEmpty()) {
+    aString.Truncate();
+    return NS_OK;
+  }
+
+  uint32_t stringLen = ((aBinaryData.Length() + 2) / 3) * 4;
+
+  char *buffer;
+
+  // Add one byte for null termination.
+  if (aString.SetCapacity(stringLen + 1, fallible_t()) &&
+    (buffer = aString.BeginWriting()) &&
+    PL_Base64Encode(aBinaryData.BeginReading(), aBinaryData.Length(), buffer)) {
+    // PL_Base64Encode doesn't null terminate the buffer for us when we pass
+    // the buffer in. Do that manually.
+    buffer[stringLen] = '\0';
+
+    aString.SetLength(stringLen);
+    return NS_OK;
+  }
+
+  aString.Truncate();
+  return NS_ERROR_INVALID_ARG;
+}
+
+nsresult
+Base64Encode(const nsAString &aString, nsAString &aBinaryData)
+{
+  NS_LossyConvertUTF16toASCII string(aString);
+  nsAutoCString binaryData;
+
+  nsresult rv = Base64Encode(string, binaryData);
+  if (NS_SUCCEEDED(rv)) {
+    CopyASCIItoUTF16(binaryData, aBinaryData);
+  } else {
+    aBinaryData.Truncate();
+  }
+
+  return rv;
+}
+
+nsresult
+Base64Decode(const nsACString &aString, nsACString &aBinaryData)
+{
+  // Check for overflow.
+  if (aString.Length() > UINT32_MAX / 3) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // Don't ask PR_Base64Decode to decode the empty string
+  if (aString.IsEmpty()) {
+    aBinaryData.Truncate();
+    return NS_OK;
+  }
+
+  uint32_t binaryDataLen = ((aString.Length() * 3) / 4);
+
+  char *buffer;
+
+  // Add one byte for null termination.
+  if (aBinaryData.SetCapacity(binaryDataLen + 1, fallible_t()) &&
+    (buffer = aBinaryData.BeginWriting()) &&
+    PL_Base64Decode(aString.BeginReading(), aString.Length(), buffer)) {
+    // PL_Base64Decode doesn't null terminate the buffer for us when we pass
+    // the buffer in. Do that manually, taking into account the number of '='
+    // characters we were passed.
+    if (!aString.IsEmpty() && aString[aString.Length() - 1] == '=') {
+      if (aString.Length() > 1 && aString[aString.Length() - 2] == '=') {
+        binaryDataLen -= 2;
+      } else {
+        binaryDataLen -= 1;
+      }
+    }
+    buffer[binaryDataLen] = '\0';
+
+    aBinaryData.SetLength(binaryDataLen);
+    return NS_OK;
+  }
+
+  aBinaryData.Truncate();
+  return NS_ERROR_INVALID_ARG;
+}
+
+nsresult
+Base64Decode(const nsAString &aBinaryData, nsAString &aString)
+{
+  NS_LossyConvertUTF16toASCII binaryData(aBinaryData);
+  nsAutoCString string;
+
+  nsresult rv = Base64Decode(binaryData, string);
+  if (NS_SUCCEEDED(rv)) {
+    CopyASCIItoUTF16(string, aString);
+  } else {
+    aString.Truncate();
+  }
+
+  return rv;
+}
+
+} // namespace mozilla