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-rw-r--r--intl/uconv/nsUnicodeToUTF8.cpp165
1 files changed, 165 insertions, 0 deletions
diff --git a/intl/uconv/nsUnicodeToUTF8.cpp b/intl/uconv/nsUnicodeToUTF8.cpp
new file mode 100644
index 000000000..aff52d176
--- /dev/null
+++ b/intl/uconv/nsUnicodeToUTF8.cpp
@@ -0,0 +1,165 @@
+/* -*- 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/. */
+
+//----------------------------------------------------------------------
+// Global functions and data [declaration]
+#include "nsUnicodeToUTF8.h"
+#include "mozilla/CheckedInt.h"
+
+NS_IMPL_ISUPPORTS(nsUnicodeToUTF8, nsIUnicodeEncoder)
+
+//----------------------------------------------------------------------
+// nsUnicodeToUTF8 class [implementation]
+
+NS_IMETHODIMP nsUnicodeToUTF8::GetMaxLength(const char16_t* aSrc,
+ int32_t aSrcLength,
+ int32_t* aDestLength)
+{
+ MOZ_ASSERT(aDestLength);
+
+ // aSrc is interpreted as UTF16, 3 is normally enough.
+ // But when previous buffer only contains part of the surrogate pair, we
+ // need to complete it here. If the first word in following buffer is not
+ // in valid surrogate range, we need to convert the remaining of last buffer
+ // to 3 bytes.
+ mozilla::CheckedInt32 length = aSrcLength;
+ length *= 3;
+ length += 3;
+
+ if (!length.isValid()) {
+ return NS_ERROR_OUT_OF_MEMORY;
+ }
+
+ *aDestLength = length.value();
+ return NS_OK;
+}
+
+NS_IMETHODIMP nsUnicodeToUTF8::Convert(const char16_t* aSrc,
+ int32_t* aSrcLength,
+ char* aDest,
+ int32_t* aDestLength)
+{
+ const char16_t* src = aSrc;
+ const char16_t* srcEnd = aSrc + *aSrcLength;
+ char* dest = aDest;
+ int32_t destLen = *aDestLength;
+ uint32_t n;
+
+ //complete remaining of last conversion
+ if (mHighSurrogate) {
+ if (src < srcEnd) {
+ *aDestLength = 0;
+ return NS_OK_UENC_MOREINPUT;
+ }
+ if (*aDestLength < 4) {
+ *aSrcLength = 0;
+ *aDestLength = 0;
+ return NS_OK_UENC_MOREOUTPUT;
+ }
+ if (*src < (char16_t)0xdc00 || *src > (char16_t)0xdfff) { //not a pair
+ *dest++ = (char)0xef; //replacement character
+ *dest++ = (char)0xbf;
+ *dest++ = (char)0xbd;
+ destLen -= 3;
+ } else {
+ n = ((mHighSurrogate - (char16_t)0xd800) << 10) +
+ (*src - (char16_t)0xdc00) + 0x10000;
+ *dest++ = (char)0xf0 | (n >> 18);
+ *dest++ = (char)0x80 | ((n >> 12) & 0x3f);
+ *dest++ = (char)0x80 | ((n >> 6) & 0x3f);
+ *dest++ = (char)0x80 | (n & 0x3f);
+ ++src;
+ destLen -= 4;
+ }
+ mHighSurrogate = 0;
+ }
+
+ while (src < srcEnd) {
+ if ( *src <= 0x007f) {
+ if (destLen < 1)
+ goto error_more_output;
+ *dest++ = (char)*src;
+ --destLen;
+ } else if (*src <= 0x07ff) {
+ if (destLen < 2)
+ goto error_more_output;
+ *dest++ = (char)0xc0 | (*src >> 6);
+ *dest++ = (char)0x80 | (*src & 0x003f);
+ destLen -= 2;
+ } else if (*src >= (char16_t)0xd800 && *src <= (char16_t)0xdfff) {
+ if (*src >= (char16_t)0xdc00) { //not a pair
+ if (destLen < 3)
+ goto error_more_output;
+ *dest++ = (char)0xef; //replacement character
+ *dest++ = (char)0xbf;
+ *dest++ = (char)0xbd;
+ destLen -= 3;
+ ++src;
+ continue;
+ }
+ if ((src+1) >= srcEnd) {
+ //we need another surrogate to complete this unicode char
+ mHighSurrogate = *src;
+ *aDestLength = dest - aDest;
+ return NS_OK_UENC_MOREINPUT;
+ }
+ //handle surrogate
+ if (destLen < 4)
+ goto error_more_output;
+ if (*(src+1) < (char16_t)0xdc00 || *(src+1) > 0xdfff) { //not a pair
+ *dest++ = (char)0xef; //replacement character
+ *dest++ = (char)0xbf;
+ *dest++ = (char)0xbd;
+ destLen -= 3;
+ } else {
+ n = ((*src - (char16_t)0xd800) << 10) + (*(src+1) - (char16_t)0xdc00) + (uint32_t)0x10000;
+ *dest++ = (char)0xf0 | (n >> 18);
+ *dest++ = (char)0x80 | ((n >> 12) & 0x3f);
+ *dest++ = (char)0x80 | ((n >> 6) & 0x3f);
+ *dest++ = (char)0x80 | (n & 0x3f);
+ destLen -= 4;
+ ++src;
+ }
+ } else {
+ if (destLen < 3)
+ goto error_more_output;
+ //treat rest of the character as BMP
+ *dest++ = (char)0xe0 | (*src >> 12);
+ *dest++ = (char)0x80 | ((*src >> 6) & 0x003f);
+ *dest++ = (char)0x80 | (*src & 0x003f);
+ destLen -= 3;
+ }
+ ++src;
+ }
+
+ *aDestLength = dest - aDest;
+ return NS_OK;
+
+error_more_output:
+ *aSrcLength = src - aSrc;
+ *aDestLength = dest - aDest;
+ return NS_OK_UENC_MOREOUTPUT;
+}
+
+NS_IMETHODIMP nsUnicodeToUTF8::Finish(char * aDest, int32_t * aDestLength)
+{
+ char * dest = aDest;
+
+ if (mHighSurrogate) {
+ if (*aDestLength < 3) {
+ *aDestLength = 0;
+ return NS_OK_UENC_MOREOUTPUT;
+ }
+ *dest++ = (char)0xef; //replacement character
+ *dest++ = (char)0xbf;
+ *dest++ = (char)0xbd;
+ mHighSurrogate = 0;
+ *aDestLength = 3;
+ return NS_OK;
+ }
+
+ *aDestLength = 0;
+ return NS_OK;
+}