tools/gn/deps_iterator.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "tools/gn/deps_iterator.h"
   6
   7 #include "tools/gn/target.h"
   8
   9 DepsIterator::DepsIterator() : current_index_(0) {
  10   vect_stack_[0] = nullptr;
  11   vect_stack_[1] = nullptr;
  12   vect_stack_[2] = nullptr;
  13 }
  14
  15 DepsIterator::DepsIterator(const LabelTargetVector* a,
  16                            const LabelTargetVector* b,
  17                            const LabelTargetVector* c)
  18     : current_index_(0) {
  19   vect_stack_[0] = a;
  20   vect_stack_[1] = b;
  21   vect_stack_[2] = c;
  22
  23   if (vect_stack_[0] && vect_stack_[0]->empty())
  24     operator++();
  25 }
  26
  27 // Advance to the next position. This assumes there are more vectors.
  28 //
  29 // For internal use, this function tolerates an initial index equal to the
  30 // length of the current vector. In this case, it will advance to the next
  31 // one.
  32 DepsIterator& DepsIterator::operator++() {
  33   DCHECK(vect_stack_[0]);
  34
  35   current_index_++;
  36   if (current_index_ >= vect_stack_[0]->size()) {
  37     // Advance to next vect. Shift the elements left by one.
  38     vect_stack_[0] = vect_stack_[1];
  39     vect_stack_[1] = vect_stack_[2];
  40     vect_stack_[2] = nullptr;
  41
  42     current_index_ = 0;
  43
  44     if (vect_stack_[0] && vect_stack_[0]->empty())
  45       operator++();
  46   }
  47   return *this;
  48 }
  49
  50 DepsIteratorRange::DepsIteratorRange(const DepsIterator& b)
  51     : begin_(b),
  52       end_() {
  53 }
  54
  55 DepsIteratorRange::~DepsIteratorRange() {
  56 }