| // Copyright 2014 The Chromium Authors. All rights reserved. |

| // Use of this source code is governed by a BSD-style license that can be |

| // found in the LICENSE file. |

| |

| #include "tools/gn/deps_iterator.h" |

| |

| #include "tools/gn/target.h" |

| |

| DepsIterator::DepsIterator() : current_index_(0) { |

| vect_stack_[0] = nullptr; |

| vect_stack_[1] = nullptr; |

| vect_stack_[2] = nullptr; |

| } |

| |

| DepsIterator::DepsIterator(const LabelTargetVector* a, |

| const LabelTargetVector* b, |

| const LabelTargetVector* c) |

| : current_index_(0) { |

| vect_stack_[0] = a; |

| vect_stack_[1] = b; |

| vect_stack_[2] = c; |

| |

| if (vect_stack_[0] && vect_stack_[0]->empty()) |

| operator++(); |

| } |

| |

| // Advance to the next position. This assumes there are more vectors. |

| // |

| // For internal use, this function tolerates an initial index equal to the |

| // length of the current vector. In this case, it will advance to the next |

| // one. |

| DepsIterator& DepsIterator::operator++() { |

| DCHECK(vect_stack_[0]); |

| |

| current_index_++; |

| if (current_index_ >= vect_stack_[0]->size()) { |

| // Advance to next vect. Shift the elements left by one. |

| vect_stack_[0] = vect_stack_[1]; |

| vect_stack_[1] = vect_stack_[2]; |

| vect_stack_[2] = nullptr; |

| |

| current_index_ = 0; |

| |

| if (vect_stack_[0] && vect_stack_[0]->empty()) |

| operator++(); |

| } |

| return *this; |

| } |

| |

| DepsIteratorRange::DepsIteratorRange(const DepsIterator& b) |

| : begin_(b), end_() {} |

| |

| DepsIteratorRange::~DepsIteratorRange() = default; |