third_party/blink/renderer/core/svg/svg_parsing_error.h

/*
 * Copyright (C) Research In Motion Limited 2011. All rights reserved.
 * Copyright (C) 2011 Apple, Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_SVG_SVG_PARSING_ERROR_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_SVG_SVG_PARSING_ERROR_H_

#include "third_party/blink/renderer/platform/wtf/math_extras.h"
#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"

namespace blink {

class QualifiedName;

enum class SVGParseStatus {
  kNoError,

  // Syntax errors
  kTrailingGarbage,
  kExpectedAngle,
  kExpectedArcFlag,
  kExpectedBoolean,
  kExpectedEndOfArguments,
  kExpectedEnumeration,
  kExpectedInteger,
  kExpectedLength,
  kExpectedMoveToCommand,
  kExpectedNumber,
  kExpectedNumberOrPercentage,
  kExpectedPathCommand,
  kExpectedStartOfArguments,
  kExpectedTransformFunction,

  // Semantic errors
  kNegativeValue,
  kZeroValue,

  // Generic error
  kParsingFailed,
};

class SVGParsingError {
  STACK_ALLOCATED();

 public:
  SVGParsingError(SVGParseStatus status = SVGParseStatus::kNoError,
                  size_t locus = 0)
      : status_(static_cast<unsigned>(status)), locus_(CheckLocus(locus)) {
    DCHECK_EQ(Status(), status);
  }

  SVGParseStatus Status() const { return static_cast<SVGParseStatus>(status_); }

  bool HasLocus() const { return locus_ != kNoLocus; }
  unsigned Locus() const { return locus_; }

  // Move the locus of this error by |offset|, returning in a new error.
  SVGParsingError OffsetWith(size_t offset) const {
    return SVGParsingError(Status(), offset + Locus());
  }

  // Generates a string describing this error for |value| in the context of
  // an <element, attribute>-name pair.
  String Format(const String& tag_name,
                const QualifiedName&,
                const AtomicString& value) const;

 private:
  static const int kLocusBits = 24;
  static const unsigned kNoLocus = (1u << kLocusBits) - 1;

  static unsigned CheckLocus(size_t locus) {
    // Clamp to fit in the number of bits available. If the character index
    // encoded by the locus does not fit in the number of bits allocated
    // for it, the locus will be disabled (set to kNoLocus). This means
    // that very long values will be output in their entirety. That should
    // however be rather uncommon.
    return clampTo<unsigned>(locus, 0, kNoLocus);
  }

  unsigned status_ : 8;
  unsigned locus_ : kLocusBits;  // The locus (character index) of the error
                                 // within the parsed string.
};

inline bool operator==(const SVGParsingError& error, SVGParseStatus status) {
  return error.Status() == status;
}
inline bool operator!=(const SVGParsingError& error, SVGParseStatus status) {
  return !(error == status);
}

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_SVG_SVG_PARSING_ERROR_H_