string-stream.cc.svn-base

Google浏览器V8内核代码

// Copyright 2006-2008 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
//       disclaimer in the documentation and/or other materials provided
//       with the distribution.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#include "v8.h"

#include "factory.h"
#include "string-stream.h"

namespace v8 { namespace internal {

static const int kMentionedObjectCacheMaxSize = 256;
static List<HeapObject*, PreallocatedStorage>* debug_object_cache = NULL;
static Object* current_security_token = NULL;


char* HeapStringAllocator::allocate(unsigned bytes) {
  space_ = NewArray<char>(bytes);
  return space_;
}


NoAllocationStringAllocator::NoAllocationStringAllocator(unsigned bytes) {
  size_ = bytes;
  space_ = NewArray<char>(bytes);
}


NoAllocationStringAllocator::NoAllocationStringAllocator(char* memory,
                                                         unsigned size) {
  size_ = size;
  space_ = memory;
}


bool StringStream::Put(char c) {
  if (space() == 0) return false;
  if (length_ >= capacity_ - 1) {
    unsigned new_capacity = capacity_;
    char* new_buffer = allocator_->grow(&new_capacity);
    if (new_capacity > capacity_) {
      capacity_ = new_capacity;
      buffer_ = new_buffer;
    } else {
      // Indicate truncation with dots.
      memset(cursor(), '.', space());
      length_ = capacity_;
      buffer_[length_ - 2] = '\n';
      buffer_[length_ - 1] = '\0';
      return false;
    }
  }
  buffer_[length_] = c;
  buffer_[length_ + 1] = '\0';
  length_++;
  return true;
}


// A control character is one that configures a format element.  For
// instance, in %.5s, .5 are control characters.
static bool IsControlChar(char c) {
  switch (c) {
  case '0': case '1': case '2': case '3': case '4': case '5':
  case '6': case '7': case '8': case '9': case '.': case '-':
    return true;
  default:
    return false;
  }
}


void StringStream::Add(const char* format, Vector<FmtElm> elms) {
  // If we already ran out of space then return immediately.
  if (space() == 0)
    return;
  int offset = 0;
  int elm = 0;
  while (format[offset] != '\0') {
    if (format[offset] != '%' || elm == elms.length()) {
      Put(format[offset]);
      offset++;
      continue;
    }
    // Read this formatting directive into a temporary buffer
    EmbeddedVector<char, 24> temp;
    int format_length = 0;
    // Skip over the whole control character sequence until the
    // format element type
    temp[format_length++] = format[offset++];
    // '\0' is not a control character so we don't have to
    // explicitly check for the end of the string
    while (IsControlChar(format[offset]))
      temp[format_length++] = format[offset++];
    char type = format[offset];
    if (type == '\0') return;
    temp[format_length++] = type;
    temp[format_length] = '\0';
    offset++;
    FmtElm current = elms[elm++];
    switch (type) {
    case 's': {
      ASSERT_EQ(FmtElm::C_STR, current.type_);
      const char* value = current.data_.u_c_str_;
      Add(value);
      break;
    }
    case 'o': {
      ASSERT_EQ(FmtElm::OBJ, current.type_);
      Object* obj = current.data_.u_obj_;
      PrintObject(obj);
      break;
    }
    case 'i': case 'd': case 'u': case 'x': case 'c': case 'p': {
      int value = current.data_.u_int_;
      EmbeddedVector<char, 24> formatted;
      OS::SNPrintF(formatted, temp.start(), value);
      Add(formatted.start());
      break;
    }
    default:
      UNREACHABLE();
      break;
    }
  }

  // Verify that the buffer is 0-terminated and doesn't contain any
  // other 0-characters.
  ASSERT(buffer_[length_] == '\0');
  ASSERT(strlen(buffer_) == length_);
}


void StringStream::PrintObject(Object* o) {
  o->ShortPrint(this);
  if (o->IsString()) {
    if (String::cast(o)->length() <= String::kMaxMediumStringSize) {
      return;
    }
  } else if (o->IsNumber() || o->IsOddball()) {
    return;
  }
  if (o->IsHeapObject()) {
    for (int i = 0; i < debug_object_cache->length(); i++) {
      if ((*debug_object_cache)[i] == o) {
        Add("#%d#", i);
        return;
      }
    }
    if (debug_object_cache->length() < kMentionedObjectCacheMaxSize) {
      Add("#%d#", debug_object_cache->length());
      debug_object_cache->Add(HeapObject::cast(o));
    } else {
      Add("@%p", o);
    }
  }
}


void StringStream::Add(const char* format) {
  Add(format, Vector<FmtElm>::empty());
}


void StringStream::Add(const char* format, FmtElm arg0) {
  const char argc = 1;
  FmtElm argv[argc] = { arg0 };
  Add(format, Vector<FmtElm>(argv, argc));
}


void StringStream::Add(const char* format, FmtElm arg0, FmtElm arg1) {
  const char argc = 2;
  FmtElm argv[argc] = { arg0, arg1 };
  Add(format, Vector<FmtElm>(argv, argc));
}


void StringStream::Add(const char* format, FmtElm arg0, FmtElm arg1,
                       FmtElm arg2) {
  const char argc = 3;
  FmtElm argv[argc] = { arg0, arg1, arg2 };
  Add(format, Vector<FmtElm>(argv, argc));
}


SmartPointer<char> StringStream::ToCString() {
  char* str = NewArray<char>(length_ + 1);
  memcpy(str, buffer_, length_);
  str[length_] = '\0';
  return SmartPointer<char>(str);
}


void StringStream::Log() {
  LOG(StringEvent("StackDump", buffer_));
}


void StringStream::OutputToStdOut() {
  // Dump the output to stdout, but make sure to break it up into
  // manageable chunks to avoid losing parts of the output in the OS
  // printing code. This is a problem on Windows in particular; see
  // the VPrint() function implementations in platform-win32.cc.
  unsigned position = 0;
  for (unsigned next; (next = position + 2048) < length_; position = next) {
    char save = buffer_[next];
    buffer_[next] = '\0';
    internal::PrintF("%s", &buffer_[position]);
    buffer_[next] = save;
  }
  internal::PrintF("%s", &buffer_[position]);
}


Handle<String> StringStream::ToString() {
  return Factory::NewStringFromUtf8(Vector<const char>(buffer_, length_));
}


void StringStream::ClearMentionedObjectCache() {
  current_security_token = NULL;
  if (debug_object_cache == NULL) {
    debug_object_cache = new List<HeapObject*, PreallocatedStorage>(0);
  }
  debug_object_cache->Clear();
}


#ifdef DEBUG
bool StringStream::IsMentionedObjectCacheClear() {
  return (debug_object_cache->length() == 0);
}
#endif


bool StringStream::Put(String* str) {
  return Put(str, 0, str->length());
}


bool StringStream::Put(String* str, int start, int end) {
  StringInputBuffer name_buffer(str);
  name_buffer.Seek(start);
  for (int i = start; i < end && name_buffer.has_more(); i++) {
    int c = name_buffer.GetNext();
    if (c >= 127 || c < 32) {
      c = '?';
    }
    if (!Put(c)) {
      return false;  // Output was truncated.
    }
  }