root/src/string-stream.cc

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DEFINITIONS

This source file includes following definitions.
  1. allocate
  2. Put
  3. IsControlChar
  4. Add
  5. PrintObject
  6. Add
  7. Add
  8. Add
  9. Add
  10. Add
  11. Add
  12. ToCString
  13. Log
  14. OutputToFile
  15. ToString
  16. ClearMentionedObjectCache
  17. IsMentionedObjectCacheClear
  18. Put
  19. Put
  20. PrintName
  21. PrintUsingMap
  22. PrintFixedArray
  23. PrintByteArray
  24. PrintMentionedObjectCache
  25. PrintSecurityTokenIfChanged
  26. PrintFunction
  27. PrintPrototype
  28. grow
  29. grow

// Copyright 2012 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"

#include "allocation-inl.h"

namespace v8 {
namespace internal {

static const int kMentionedObjectCacheMaxSize = 256;

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


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


bool StringStream::Put(char c) {
  if (full()) return false;
  ASSERT(length_ < capacity_);
  // Since the trailing '\0' is not accounted for in length_ fullness is
  // indicated by a difference of 1 between length_ and capacity_. Thus when
  // reaching a difference of 2 we need to grow the buffer.
  if (length_ == capacity_ - 2) {
    unsigned new_capacity = capacity_;
    char* new_buffer = allocator_->grow(&new_capacity);
    if (new_capacity > capacity_) {
      capacity_ = new_capacity;
      buffer_ = new_buffer;
    } else {
      // Reached the end of the available buffer.
      ASSERT(capacity_ >= 5);
      length_ = capacity_ - 1;  // Indicate fullness of the stream.
      buffer_[length_ - 4] = '.';
      buffer_[length_ - 3] = '.';
      buffer_[length_ - 2] = '.';
      buffer_[length_ - 1] = '\n';
      buffer_[length_] = '\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(Vector<const char> format, Vector<FmtElm> elms) {
  // If we already ran out of space then return immediately.
  if (full()) return;
  int offset = 0;
  int elm = 0;
  while (offset < format.length()) {
    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++];
    while (offset < format.length() && IsControlChar(format[offset]))
      temp[format_length++] = format[offset++];
    if (offset >= format.length())
      return;
    char type = format[offset];
    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 'w': {
      ASSERT_EQ(FmtElm::LC_STR, current.type_);
      Vector<const uc16> value = *current.data_.u_lc_str_;
      for (int i = 0; i < value.length(); i++)
        Put(static_cast<char>(value[i]));
      break;
    }
    case 'o': {
      ASSERT_EQ(FmtElm::OBJ, current.type_);
      Object* obj = current.data_.u_obj_;
      PrintObject(obj);
      break;
    }
    case 'k': {
      ASSERT_EQ(FmtElm::INT, current.type_);
      int value = current.data_.u_int_;
      if (0x20 <= value && value <= 0x7F) {
        Put(value);
      } else if (value <= 0xff) {
        Add("\\x%02x", value);
      } else {
        Add("\\u%04x", value);
      }
      break;
    }
    case 'i': case 'd': case 'u': case 'x': case 'c': case 'X': {
      int value = current.data_.u_int_;
      EmbeddedVector<char, 24> formatted;
      int length = OS::SNPrintF(formatted, temp.start(), value);
      Add(Vector<const char>(formatted.start(), length));
      break;
    }
    case 'f': case 'g': case 'G': case 'e': case 'E': {
      double value = current.data_.u_double_;
      EmbeddedVector<char, 28> formatted;
      OS::SNPrintF(formatted, temp.start(), value);
      Add(formatted.start());
      break;
    }
    case 'p': {
      void* value = current.data_.u_pointer_;
      EmbeddedVector<char, 20> formatted;
      OS::SNPrintF(formatted, temp.start(), value);
      Add(formatted.start());
      break;
    }
    default:
      UNREACHABLE();
      break;
    }
  }

  // Verify that the buffer is 0-terminated
  ASSERT(buffer_[length_] == '\0');
}


void StringStream::PrintObject(Object* o) {
  o->ShortPrint(this);
  if (o->IsString()) {
    if (String::cast(o)->length() <= String::kMaxShortPrintLength) {
      return;
    }
  } else if (o->IsNumber() || o->IsOddball()) {
    return;
  }
  if (o->IsHeapObject()) {
    DebugObjectCache* debug_object_cache = Isolate::Current()->
        string_stream_debug_object_cache();
    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(CStrVector(format));
}


void StringStream::Add(Vector<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(CStrVector(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(CStrVector(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(CStrVector(format), Vector<FmtElm>(argv, argc));
}


void StringStream::Add(const char* format, FmtElm arg0, FmtElm arg1,
                       FmtElm arg2, FmtElm arg3) {
  const char argc = 4;
  FmtElm argv[argc] = { arg0, arg1, arg2, arg3 };
  Add(CStrVector(format), Vector<FmtElm>(argv, argc));
}


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


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


void StringStream::OutputToFile(FILE* out) {
  // 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(out, "%s", &buffer_[position]);
    buffer_[next] = save;
  }
  internal::PrintF(out, "%s", &buffer_[position]);
}


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


void StringStream::ClearMentionedObjectCache() {
  Isolate* isolate = Isolate::Current();
  isolate->set_string_stream_current_security_token(NULL);
  if (isolate->string_stream_debug_object_cache() == NULL) {
    isolate->set_string_stream_debug_object_cache(
        new List<HeapObject*, PreallocatedStorageAllocationPolicy>(0));
  }
  isolate->string_stream_debug_object_cache()->Clear();
}


#ifdef DEBUG
bool StringStream::IsMentionedObjectCacheClear() {
  return (
      Isolate::Current()->string_stream_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.
    }
  }
  return true;
}


void StringStream::PrintName(Object* name) {
  if (name->IsString()) {
    String* str = String::cast(name);
    if (str->length() > 0) {
      Put(str);
    } else {
      Add("/* anonymous */");
    }
  } else {
    Add("%o", name);
  }
}


void StringStream::PrintUsingMap(JSObject* js_object) {
  Map* map = js_object->map();
  if (!HEAP->Contains(map) ||
      !map->IsHeapObject() ||
      !map->IsMap()) {
    Add("<Invalid map>\n");
    return;
  }
  DescriptorArray* descs = map->instance_descriptors();
  for (int i = 0; i < descs->number_of_descriptors(); i++) {
    if (descs->GetType(i) == FIELD) {
      Object* key = descs->GetKey(i);
      if (key->IsString() || key->IsNumber()) {
        int len = 3;
        if (key->IsString()) {
          len = String::cast(key)->length();
        }
        for (; len < 18; len++)
          Put(' ');
        if (key->IsString()) {
          Put(String::cast(key));
        } else {
          key->ShortPrint();
        }
        Add(": ");
        Object* value = js_object->FastPropertyAt(descs->GetFieldIndex(i));
        Add("%o\n", value);
      }
    }
  }
}


void StringStream::PrintFixedArray(FixedArray* array, unsigned int limit) {
  Heap* heap = HEAP;
  for (unsigned int i = 0; i < 10 && i < limit; i++) {
    Object* element = array->get(i);
    if (element != heap->the_hole_value()) {
      for (int len = 1; len < 18; len++)
        Put(' ');
      Add("%d: %o\n", i, array->get(i));
    }
  }
  if (limit >= 10) {
    Add("                  ...\n");
  }
}


void StringStream::PrintByteArray(ByteArray* byte_array) {
  unsigned int limit = byte_array->length();
  for (unsigned int i = 0; i < 10 && i < limit; i++) {
    byte b = byte_array->get(i);
    Add("             %d: %3d 0x%02x", i, b, b);
    if (b >= ' ' && b <= '~') {
      Add(" '%c'", b);
    } else if (b == '\n') {
      Add(" '\n'");
    } else if (b == '\r') {
      Add(" '\r'");
    } else if (b >= 1 && b <= 26) {
      Add(" ^%c", b + 'A' - 1);
    }
    Add("\n");
  }
  if (limit >= 10) {
    Add("                  ...\n");
  }
}


void StringStream::PrintMentionedObjectCache() {
  DebugObjectCache* debug_object_cache =
      Isolate::Current()->string_stream_debug_object_cache();
  Add("==== Key         ============================================\n\n");
  for (int i = 0; i < debug_object_cache->length(); i++) {
    HeapObject* printee = (*debug_object_cache)[i];
    Add(" #%d# %p: ", i, printee);
    printee->ShortPrint(this);
    Add("\n");
    if (printee->IsJSObject()) {
      if (printee->IsJSValue()) {
        Add("           value(): %o\n", JSValue::cast(printee)->value());
      }
      PrintUsingMap(JSObject::cast(printee));
      if (printee->IsJSArray()) {
        JSArray* array = JSArray::cast(printee);
        if (array->HasFastObjectElements()) {
          unsigned int limit = FixedArray::cast(array->elements())->length();
          unsigned int length =
            static_cast<uint32_t>(JSArray::cast(array)->length()->Number());
          if (length < limit) limit = length;
          PrintFixedArray(FixedArray::cast(array->elements()), limit);
        }
      }
    } else if (printee->IsByteArray()) {
      PrintByteArray(ByteArray::cast(printee));
    } else if (printee->IsFixedArray()) {
      unsigned int limit = FixedArray::cast(printee)->length();
      PrintFixedArray(FixedArray::cast(printee), limit);
    }
  }
}


void StringStream::PrintSecurityTokenIfChanged(Object* f) {
  Isolate* isolate = Isolate::Current();
  Heap* heap = isolate->heap();
  if (!f->IsHeapObject() || !heap->Contains(HeapObject::cast(f))) {
    return;
  }
  Map* map = HeapObject::cast(f)->map();
  if (!map->IsHeapObject() ||
      !heap->Contains(map) ||
      !map->IsMap() ||
      !f->IsJSFunction()) {
    return;
  }

  JSFunction* fun = JSFunction::cast(f);
  Object* perhaps_context = fun->unchecked_context();
  if (perhaps_context->IsHeapObject() &&
      heap->Contains(HeapObject::cast(perhaps_context)) &&
      perhaps_context->IsContext()) {
    Context* context = fun->context();
    if (!heap->Contains(context)) {
      Add("(Function context is outside heap)\n");
      return;
    }
    Object* token = context->global_context()->security_token();
    if (token != isolate->string_stream_current_security_token()) {
      Add("Security context: %o\n", token);
      isolate->set_string_stream_current_security_token(token);
    }
  } else {
    Add("(Function context is corrupt)\n");
  }
}


void StringStream::PrintFunction(Object* f, Object* receiver, Code** code) {
  if (f->IsHeapObject() &&
      HEAP->Contains(HeapObject::cast(f)) &&
      HEAP->Contains(HeapObject::cast(f)->map()) &&
      HeapObject::cast(f)->map()->IsMap()) {
    if (f->IsJSFunction()) {
      JSFunction* fun = JSFunction::cast(f);
      // Common case: on-stack function present and resolved.
      PrintPrototype(fun, receiver);
      *code = fun->code();
    } else if (f->IsSymbol()) {
      // Unresolved and megamorphic calls: Instead of the function
      // we have the function name on the stack.
      PrintName(f);
      Add("/* unresolved */ ");
    } else {
      // Unless this is the frame of a built-in function, we should always have
      // the callee function or name on the stack. If we don't, we have a
      // problem or a change of the stack frame layout.
      Add("%o", f);
      Add("/* warning: no JSFunction object or function name found */ ");
    }
    /* } else if (is_trampoline()) {
       Print("trampoline ");
    */
  } else {
    if (!f->IsHeapObject()) {
      Add("/* warning: 'function' was not a heap object */ ");
      return;
    }
    if (!HEAP->Contains(HeapObject::cast(f))) {
      Add("/* warning: 'function' was not on the heap */ ");
      return;
    }
    if (!HEAP->Contains(HeapObject::cast(f)->map())) {
      Add("/* warning: function's map was not on the heap */ ");
      return;
    }
    if (!HeapObject::cast(f)->map()->IsMap()) {
      Add("/* warning: function's map was not a valid map */ ");
      return;
    }
    Add("/* warning: Invalid JSFunction object found */ ");
  }
}


void StringStream::PrintPrototype(JSFunction* fun, Object* receiver) {
  Object* name = fun->shared()->name();
  bool print_name = false;
  Heap* heap = HEAP;
  for (Object* p = receiver; p != heap->null_value(); p = p->GetPrototype()) {
    if (p->IsJSObject()) {
      Object* key = JSObject::cast(p)->SlowReverseLookup(fun);
      if (key != heap->undefined_value()) {
        if (!name->IsString() ||
            !key->IsString() ||
            !String::cast(name)->Equals(String::cast(key))) {
          print_name = true;
        }
        if (name->IsString() && String::cast(name)->length() == 0) {
          print_name = false;
        }
        name = key;
      }
    } else {
      print_name = true;
    }
  }
  PrintName(name);
  // Also known as - if the name in the function doesn't match the name under
  // which it was looked up.
  if (print_name) {
    Add("(aka ");
    PrintName(fun->shared()->name());
    Put(')');
  }
}


char* HeapStringAllocator::grow(unsigned* bytes) {
  unsigned new_bytes = *bytes * 2;
  // Check for overflow.
  if (new_bytes <= *bytes) {
    return space_;
  }
  char* new_space = NewArray<char>(new_bytes);
  if (new_space == NULL) {
    return space_;
  }
  memcpy(new_space, space_, *bytes);
  *bytes = new_bytes;
  DeleteArray(space_);
  space_ = new_space;
  return new_space;
}


// Only grow once to the maximum allowable size.
char* NoAllocationStringAllocator::grow(unsigned* bytes) {
  ASSERT(size_ >= *bytes);
  *bytes = size_;
  return space_;
}


} }  // namespace v8::internal

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