1 files changed, 165 insertions, 0 deletions
diff --git a/intl/uconv/ucvtw/nsBIG5ToUnicode.cpp b/intl/uconv/ucvtw/nsBIG5ToUnicode.cpp
new file mode 100644
index 000000000..8dbf84a14
--- /dev/null
+++ b/intl/uconv/ucvtw/nsBIG5ToUnicode.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/. */
+
+#include "nsBIG5ToUnicode.h"
+#include "mozilla/BinarySearch.h"
+#include "mozilla/ArrayUtils.h"
+#include "nsBIG5Data.h"
+
+nsBIG5ToUnicode::nsBIG5ToUnicode()
+ : mPendingTrail(0)
+ , mBig5Lead(0)
+{
+}
+
+NS_IMETHODIMP
+nsBIG5ToUnicode::Convert(const char* aSrc,
+                         int32_t* aSrcLength,
+                         char16_t* aDest,
+                         int32_t* aDestLength)
+{
+  // We'll be doing comparisons as unsigned.
+  const uint8_t* in = reinterpret_cast<const uint8_t*>(aSrc);
+  const uint8_t* inEnd = in + *aSrcLength;
+  char16_t* out = aDest;
+  char16_t* outEnd = out + *aDestLength;
+
+  if (mPendingTrail) {
+    if (out == outEnd) {
+      *aSrcLength = 0;
+      *aDestLength = 0;
+      return NS_OK_UDEC_MOREOUTPUT;
+    }
+    *out++ = mPendingTrail;
+    mPendingTrail = 0;
+  }
+  for (;;) {
+    if (in == inEnd) {
+      *aSrcLength = in - reinterpret_cast<const uint8_t*>(aSrc);
+      *aDestLength = out - aDest;
+      return mBig5Lead ? NS_OK_UDEC_MOREINPUT : NS_OK;
+    }
+    if (out == outEnd) {
+      *aSrcLength = in - reinterpret_cast<const uint8_t*>(aSrc);
+      *aDestLength = out - aDest;
+      return NS_OK_UDEC_MOREOUTPUT;
+    }
+    uint8_t b = *in++;
+    if (!mBig5Lead) {
+      if (b <= 0x7F) {
+        *out++ = (char16_t)b;
+        continue;
+      }
+      if (b >= 0x81 && b <= 0xFE) {
+        mBig5Lead = b;
+        continue;
+      }
+      if (mErrBehavior == kOnError_Signal) {
+        --in;
+        *aSrcLength = in - reinterpret_cast<const uint8_t*>(aSrc);
+        *aDestLength = out - aDest;
+        return NS_ERROR_ILLEGAL_INPUT;
+      }
+      *out++ = 0xFFFD;
+      continue;
+    }
+    size_t lead = mBig5Lead;
+    mBig5Lead = 0;
+    size_t offset = (b < 0x7F) ? 0x40 : 0x62;
+    if ((b >= 0x40 && b <= 0x7E) || (b >= 0xA1 && b <= 0xFE)) {
+      size_t pointer = (lead - 0x81) * 157L + (b - offset);
+      char16_t outTrail;
+      switch (pointer) {
+        case 1133:
+          *out++ = 0x00CA;
+          outTrail = 0x0304;
+          break;
+        case 1135:
+          *out++ = 0x00CA;
+          outTrail = 0x030C;
+          break;
+        case 1164:
+          *out++ = 0x00EA;
+          outTrail = 0x0304;
+          break;
+        case 1166:
+          *out++ = 0x00EA;
+          outTrail = 0x030C;
+          break;
+        default:
+          char16_t lowBits = nsBIG5Data::LowBits(pointer);
+          if (!lowBits) {
+            if (b <= 0x7F) {
+              // prepend byte to stream
+              // Always legal, since we've always just read a byte
+              // if we come here.
+              --in;
+            }
+            if (mErrBehavior == kOnError_Signal) {
+              --in;
+              *aSrcLength = in - reinterpret_cast<const uint8_t*>(aSrc);
+              *aDestLength = out - aDest;
+              return NS_ERROR_ILLEGAL_INPUT;
+            }
+            *out++ = 0xFFFD;
+            continue;
+          }
+          if (nsBIG5Data::IsAstral(pointer)) {
+            uint32_t codePoint = uint32_t(lowBits) | 0x20000;
+            *out++ = char16_t(0xD7C0 + (codePoint >> 10));
+            outTrail = char16_t(0xDC00 + (codePoint & 0x3FF));
+            break;
+          }
+          *out++ = lowBits;
+          continue;
+      }
+      if (out == outEnd) {
+        mPendingTrail = outTrail;
+        *aSrcLength = in - reinterpret_cast<const uint8_t*>(aSrc);
+        *aDestLength = out - aDest;
+        return NS_OK_UDEC_MOREOUTPUT;
+      }
+      *out++ = outTrail;
+      continue;
+    }
+    // pointer is null
+    if (b <= 0x7F) {
+      // prepend byte to stream
+      // Always legal, since we've always just read a byte
+      // if we come here.
+      --in;
+    }
+    if (mErrBehavior == kOnError_Signal) {
+      // Moving in one past the start of aSrc is actually OK per API contract,
+      // since assigning -1 to aSrcLength means that we want the caller to
+      // record one U+FFFD and repush the same input buffer.
+      --in;
+      *aSrcLength = in - reinterpret_cast<const uint8_t*>(aSrc);
+      *aDestLength = out - aDest;
+      return NS_ERROR_ILLEGAL_INPUT;
+    }
+    *out++ = 0xFFFD;
+    continue;
+  }
+}
+
+NS_IMETHODIMP
+nsBIG5ToUnicode::GetMaxLength(const char* aSrc,
+                              int32_t aSrcLength,
+                              int32_t* aDestLength)
+{
+  // The length of the output in UTF-16 code units never exceeds the length
+  // of the input in bytes.
+  *aDestLength = aSrcLength + (mPendingTrail ? 1 : 0) + (mBig5Lead ? 1 : 0);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsBIG5ToUnicode::Reset()
+{
+  mPendingTrail = 0;
+  mBig5Lead = 0;
+  return NS_OK;
+}