Complete the switch to ServiceObject

runtime/platform/json.cc

Index: runtime/platform/json.cc
diff --git a/runtime/platform/json.cc b/runtime/platform/json.cc
index a406e7a5728bf96303387fbaa070c0e2af6f55a0..cc57a4b5bd72b676c8794c7977021ff86ec094cd 100644
--- a/runtime/platform/json.cc
+++ b/runtime/platform/json.cc
@@ -642,6 +642,23 @@ void TextBuffer::AddEscapedString(const char* s) {
 }
 
 
+void TextBuffer::AddEscapedUTF8String(const char* s) {
+  intptr_t len = strlen(s);
+  const uint8_t* s8 = reinterpret_cast<const uint8_t*>(s);
+  intptr_t i = 0;
+  for (; i < len; ) {
+    // Extract next UTF8 character.
+    uint32_t ch = 0;
+    uint32_t ch_len = Utf8Decode(&s8[i], len - i, &ch);
+    ASSERT(ch_len != 0);
+    AddEscapedChar(ch);
+    // Move i forward.
+    i += ch_len;
+  }
+  ASSERT(i == len);
+}
+
+
 void TextBuffer::EnsureCapacity(intptr_t len) {
   intptr_t remaining = buf_size_ - msg_len_;
   if (remaining <= len) {
@@ -658,4 +675,100 @@ void TextBuffer::EnsureCapacity(intptr_t len) {
   }
 }
 
+
+static const uint32_t kMaxCodePoint = 0x10FFFF;

[turnidge, 2014/03/10 21:03:28]

I don't like duplicating the existing unicode decode logic that is in
vm/unicode.{h/cc}.  Can you find a way to move that code up to platform so it
can be shared?  Perhaps the unicode change should become part of a separate cl?

+
+
+static const int8_t kTrailBytes[256] = {
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+  3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+  4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 0, 0
+};
+
+
+static const uint32_t kMagicBits[7] = {
+  0,  // Padding.
+  0x00000000,
+  0x00003080,
+  0x000E2080,
+  0x03C82080,
+  0xFA082080,
+  0x82082080
+};
+
+
+// Minimum values of code points used to check shortest form.
+static const uint32_t kOverlongMinimum[7] = {
+  0,  // Padding.
+  0x0,
+  0x80,
+  0x800,
+  0x10000,
+  0xFFFFFFFF,
+  0xFFFFFFFF
+};
+
+
+static bool IsTrailByte(uint8_t code_unit) {
+  return (code_unit & 0xC0) == 0x80;
+}
+
+static bool IsOutOfRange(uint32_t code_point) {
+  return code_point > kMaxCodePoint;
+}
+
+
+static bool IsNonShortestForm(uint32_t code_point, size_t num_code_units) {
+  return code_point < kOverlongMinimum[num_code_units];
+}
+
+static bool IsSurrogate(int32_t ch) {
+  return (ch & 0xFFFFF800) == 0xD800;
+}
+
+uint32_t TextBuffer::Utf8Decode(
+    const uint8_t* utf8_array, intptr_t array_len, uint32_t* dst) {
+  uint32_t ch = utf8_array[0] & 0xFF;
+  intptr_t i = 1;
+  if (ch >= 0x80) {
+    intptr_t num_trail_bytes = kTrailBytes[ch];
+    bool is_malformed = false;
+    for (; i < num_trail_bytes; ++i) {
+      if (i < array_len) {
+        uint8_t code_unit = utf8_array[i];
+        is_malformed |= !IsTrailByte(code_unit);
+        ch = (ch << 6) + code_unit;
+      } else {
+        *dst = -1;
+        return 0;
+      }
+    }
+    ch -= kMagicBits[num_trail_bytes];
+    if (!((is_malformed == false) &&
+          (i == num_trail_bytes) &&
+          !IsOutOfRange(ch) &&
+          !IsNonShortestForm(ch, i) &&
+          !IsSurrogate(ch))) {
+      *dst = -1;
+      return 0;
+    }
+  }
+  *dst = ch;
+  return i;
+}
+
+
 }  // namespace dart