Revert 214254 "Add initial prototype for the GN meta-buildsystem."

trunk/src/tools/gn/pattern.cc

-// Copyright (c) 2013 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/pattern.h"
-
-#include "tools/gn/value.h"
-
-namespace {
-
-void ParsePattern(const std::string& s, std::vector<Pattern::Subrange>* out) {
-  // Set when the last subrange is a literal so we can just append when we
-  // find another literal.
-  Pattern::Subrange* last_literal = NULL;
-
-  for (size_t i = 0; i < s.size(); i++) {
-    if (s[i] == '*') {
-      // Don't allow two **.
-      if (out->size() == 0 ||
-          (*out)[out->size() - 1].type != Pattern::Subrange::ANYTHING)
-        out->push_back(Pattern::Subrange(Pattern::Subrange::ANYTHING));
-      last_literal = NULL;
-    } else if (s[i] == '\\') {
-      if (i < s.size() - 1 && s[i + 1] == 'b') {
-        // "\b" means path boundary.
-        i++;
-        out->push_back(Pattern::Subrange(Pattern::Subrange::PATH_BOUNDARY));
-        last_literal = NULL;
-      } else {
-        // Backslash + anything else means that literal char.
-        if (!last_literal) {
-          out->push_back(Pattern::Subrange(Pattern::Subrange::LITERAL));
-          last_literal = &(*out)[out->size() - 1];
-        }
-        if (i < s.size() - 1) {
-          i++;
-          last_literal->literal.push_back(s[i]);
-        } else {
-          // Single backslash at end, use literal backslash.
-          last_literal->literal.push_back('\\');
-        }
-      }
-    } else {
-      if (!last_literal) {
-        out->push_back(Pattern::Subrange(Pattern::Subrange::LITERAL));
-        last_literal = &(*out)[out->size() - 1];
-      }
-      last_literal->literal.push_back(s[i]);
-    }
-  }
-}
-
-}  // namespace
-
-Pattern::Pattern(const std::string& s) {
-  ParsePattern(s, &subranges_);
-  is_suffix_ =
-      (subranges_.size() == 2 &&
-       subranges_[0].type == Subrange::ANYTHING &&
-       subranges_[1].type == Subrange::LITERAL);
-}
-
-Pattern::~Pattern() {
-}
-
-bool Pattern::MatchesString(const std::string& s) const {
-  // Empty pattern matches only empty string.
-  if (subranges_.empty())
-    return s.empty();
-
-  if (is_suffix_) {
-    const std::string& suffix = subranges_[1].literal;
-    if (suffix.size() > s.size())
-      return false;  // Too short.
-    return s.compare(s.size() - suffix.size(), suffix.size(), suffix) == 0;
-  }
-
-  return RecursiveMatch(s, 0, 0, true);
-}
-
-// We assume the number of ranges is small so recursive is always reasonable.
-// Could be optimized to only be recursive for *.
-bool Pattern::RecursiveMatch(const std::string& s,
-                             size_t begin_char,
-                             size_t subrange_index,
-                             bool allow_implicit_path_boundary) const {
-  if (subrange_index >= subranges_.size()) {
-    // Hit the end of our subranges, the text should also be at the end for a
-    // match.
-    return begin_char == s.size();
-  }
-
-  const Subrange& sr = subranges_[subrange_index];
-  switch (sr.type) {
-    case Subrange::LITERAL: {
-      if (s.size() - begin_char < sr.literal.size())
-        return false;  // Not enough room.
-      if (s.compare(begin_char, sr.literal.size(), sr.literal) != 0)
-        return false;  // Literal doesn't match.
-
-      // Recursively check the next one.
-      return RecursiveMatch(s, begin_char + sr.literal.size(),
-                            subrange_index + 1, true);
-    }
-
-    case Subrange::PATH_BOUNDARY: {
-      // When we can accept an implicit path boundary, we have to check both
-      // a match of the literal and the implicit one.
-      if (allow_implicit_path_boundary &&
-          (begin_char == 0 || begin_char == s.size())) {
-        // At implicit path boundary, see if the rest of the pattern matches.
-        if (RecursiveMatch(s, begin_char, subrange_index + 1, false))
-          return true;
-      }
-
-      // Check for a literal "/".
-      if (begin_char < s.size() && s[begin_char] == '/') {
-        // At explicit boundary, see if the rest of the pattern matches.
-        if (RecursiveMatch(s, begin_char + 1, subrange_index + 1, true))
-          return true;
-      }
-      return false;
-    }
-
-    case Subrange::ANYTHING: {
-      if (subrange_index == subranges_.size() - 1)
-        return true;  // * at the end, consider it matching.
-
-      size_t min_next_size = sr.MinSize();
-
-      // We don't care about exactly what matched as long as there was a match,
-      // so we can do this front-to-back. If we needed the match, we would
-      // normally want "*" to be greedy so would work backwards.
-      for (size_t i = begin_char; i < s.size() - min_next_size; i++) {
-        // Note: this could probably be faster by detecting the type of the
-        // next match in advance and checking for a match in this loop rather
-        // than doing a full recursive call for each character.
-        if (RecursiveMatch(s, i, subrange_index + 1, true))
-          return true;
-      }
-      return false;
-    }
-
-    default:
-      NOTREACHED();
-  }
-
-  return false;
-}
-
-PatternList::PatternList() {
-}
-
-PatternList::~PatternList() {
-}
-
-void PatternList::SetFromValue(const Value& v, Err* err) {
-  patterns_.clear();
-
-  if (v.type() != Value::LIST) {
-    *err = Err(v.origin(), "This value must be a list.");
-    return;
-  }
-
-  const std::vector<Value>& list = v.list_value();
-  for (size_t i = 0; i < list.size(); i++) {
-    if (!list[i].VerifyTypeIs(Value::STRING, err))
-      return;
-    patterns_.push_back(Pattern(list[i].string_value()));
-  }
-}
-
-bool PatternList::MatchesString(const std::string& s) const {
-  for (size_t i = 0; i < patterns_.size(); i++) {
-    if (patterns_[i].MatchesString(s))
-      return true;
-  }
-  return false;
-}
-
-bool PatternList::MatchesValue(const Value& v) const {
-  if (v.type() == Value::STRING)
-    return MatchesString(v.string_value());
-  return false;
-}