YugabyteDB (2.13.1.0-b60, 21121d69985fbf76aa6958d8f04a9bfa936293b5)

// Copyright 2008 Google Inc.  All rights reserved.

//

// The following only applies to changes made to this file as part of YugaByte development.

//

// Portions Copyright (c) YugaByte, Inc.

//

// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except

// in compliance with the License.  You may obtain a copy of the License at

//

// http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software distributed under the License

// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express

// or implied.  See the License for the specific language governing permissions and limitations

// under the License.

//

#include <string.h>

#include <string>

#include "yb/gutil/strings/numbers.h"

#include "yb/gutil/strings/stringpiece.h"

using std::string;

#ifndef YB_GUTIL_STRINGS_SUBSTITUTE_H

#define YB_GUTIL_STRINGS_SUBSTITUTE_H

namespace strings {

// ----------------------------------------------------------------------

// strings::Substitute()

// strings::SubstituteAndAppend()

//   Kind of like StringPrintf, but different.

//

//   Example:

//     string GetMessage(string first_name, string last_name, int age) {

//       return strings::Substitute("My name is $0 $1 and I am $2 years old.",

//                                  first_name, last_name, age);

//     }

//

//   Differences from StringPrintf:

//   * The format string does not identify the types of arguments.

//     Instead, the magic of C++ deals with this for us.  See below

//     for a list of accepted types.

//   * Substitutions in the format string are identified by a '$'

//     followed by a digit.  So, you can use arguments out-of-order and

//     use the same argument multiple times.

//   * '$$' in the format string means output a literal '$' character.

//   * It's much faster than StringPrintf.

//

//   Supported types:

//   * GStringPiece (const char*, const string&) (NULL is equivalent to "")

//     * Note that this means you do not have to add .c_str() to all of

//       your strings.  In fact, you shouldn't; it will be slower.

//   * int32, int64, uint32, uint64

//   * float, double

//   * bool:  Printed as "true" or "false".

//   * pointer types other than char*: Printed as "0x<lower case hex string>",

//             except that NULL is printed as "NULL".

//

//   If not enough arguments are supplied, a LOG(DFATAL) will be issued and

//   the empty string will be returned. If too many arguments are supplied,

//   just the first ones will be used (no warning).

//

//   SubstituteAndAppend() is like Substitute() but appends the result to

//   *output.  Example:

//

//     string str;

//     strings::SubstituteAndAppend(&str,

//                                  "My name is $0 $1 and I am $2 years old.",

//                                  first_name, last_name, age);

//

//   Substitute() is significantly faster than StringPrintf().  For very

//   large strings, it may be orders of magnitude faster.

// ----------------------------------------------------------------------

namespace internal {  // Implementation details.

// This class has implicit constructors.

// Style guide exception granted:

// http://goto/style-guide-exception-20978288

class SubstituteArg {

 public:

  // We must explicitly overload char* so that the compiler doesn't try to

  // cast it to bool to construct a DynamicSubstituteArg.  Might as well

  // overload const string& as well, since this allows us to avoid a temporary

  // object.

  // Tell PVS Studio it is OK that scratch_ is uninitialized.

  // -V:scratch_:730

  inline SubstituteArg(const char* value)  // NOLINT(runtime/explicit)

    : text_(value), size_(value == NULL ? 0 : strlen(text_)) {}

  inline SubstituteArg(const string& value)  // NOLINT(runtime/explicit)

    : text_(value.data()), size_(value.size()) {}

  inline SubstituteArg(const GStringPiece& value)  // NOLINT(runtime/explicit)

    : text_(value.data()), size_(value.size()) {}

  // Primitives

  // We don't overload for signed and unsigned char because if people are

  // explicitly declaring their chars as signed or unsigned then they are

  // probably actually using them as 8-bit integers and would probably

  // prefer an integer representation.  But, we don't really know.  So, we

  // make the caller decide what to do.

  // -V:scratch_:730

  inline SubstituteArg(char value)  // NOLINT(runtime/explicit)

    : text_(scratch_), size_(1) { scratch_[0] = value; }

  // -V:scratch_:730

  inline SubstituteArg(short value)  // NOLINT

    : text_(scratch_),

      size_(FastInt32ToBufferLeft(value, scratch_) - scratch_) {}

  // -V:scratch_:730

  inline SubstituteArg(unsigned short value)  // NOLINT

    : text_(scratch_),

      size_(FastUInt32ToBufferLeft(value, scratch_) - scratch_) {}

  // -V:scratch_:730

  inline SubstituteArg(int value)  // NOLINT

    : text_(scratch_),

      size_(FastInt32ToBufferLeft(value, scratch_) - scratch_) {}

  // -V:scratch_:730

  inline SubstituteArg(unsigned int value)  // NOLINT

    : text_(scratch_),

      size_(FastUInt32ToBufferLeft(value, scratch_) - scratch_) {}

  // -V:scratch_:730

  inline SubstituteArg(long value)  // NOLINT

    : text_(scratch_),

      size_((sizeof(value) == 4 ? FastInt32ToBufferLeft(static_cast<int32_t>(value), scratch_)

                                : FastInt64ToBufferLeft(value, scratch_))

            - scratch_) {}

  // -V:scratch_:730

  inline SubstituteArg(unsigned long value)  // NOLINT

    : text_(scratch_),

      size_((sizeof(value) == 4 ? FastUInt32ToBufferLeft(value, scratch_)

                                : FastUInt64ToBufferLeft(value, scratch_))

            - scratch_) {}

  // -V:scratch_:730

  inline SubstituteArg(long long value)  // NOLINT

    : text_(scratch_),

      size_(FastInt64ToBufferLeft(value, scratch_) - scratch_) {}

  // -V:scratch_:730

  inline SubstituteArg(unsigned long long value)  // NOLINT

    : text_(scratch_),

      size_(FastUInt64ToBufferLeft(value, scratch_) - scratch_) {}

  // -V:scratch_:730

  inline SubstituteArg(float value)  // NOLINT(runtime/explicit)

    : text_(FloatToBuffer(value, scratch_)), size_(strlen(text_)) {}

  // -V:scratch_:730

  inline SubstituteArg(double value)  // NOLINT(runtime/explicit)

    : text_(DoubleToBuffer(value, scratch_)), size_(strlen(text_)) {}

  // -V:scratch_:730

  inline SubstituteArg(bool value)  // NOLINT(runtime/explicit)

    : text_(value ? "true" : "false"), size_(strlen(text_)) {}

  // void* values, with the exception of char*, are printed as

  // StringPrintf with format "%p" would ("0x<hex value>"), with the

  // exception of NULL, which is printed as "NULL".

  SubstituteArg(const void* value);  // NOLINT(runtime/explicit)

  inline const char* data() const { return text_; }

  inline ptrdiff_t size() const { return size_; }

  // Indicates that no argument was given.

  static const SubstituteArg NoArg;

 private:

  inline SubstituteArg() : text_(NULL), size_(-1) {}

  const char* text_;

  ptrdiff_t size_;

  char scratch_[kFastToBufferSize];

};

// Return the length of the resulting string after performing the given

// substitution.

int SubstitutedSize(GStringPiece format,

                    const SubstituteArg* const* args_array);

// Perform the given substitution into 'target'. 'target' must have

// space for the result -- use SubstitutedSize() to determine how many

// bytes are required.  Returns a pointer to the next byte following

// the result in 'target'.

char* SubstituteToBuffer(GStringPiece format,

                         const SubstituteArg* const* args_array,

                         char* target);

}  // namespace internal

void SubstituteAndAppend(

  string* output, GStringPiece format,

  const internal::SubstituteArg& arg0 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg1 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg2 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg3 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg4 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg5 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg6 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg7 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg8 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg9 = internal::SubstituteArg::NoArg);

inline string Substitute(

  GStringPiece format,

  const internal::SubstituteArg& arg0 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg1 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg2 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg3 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg4 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg5 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg6 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg7 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg8 = internal::SubstituteArg::NoArg,

  const internal::SubstituteArg& arg9 = internal::SubstituteArg::NoArg) {

  string result;

  SubstituteAndAppend(&result, format, arg0, arg1, arg2, arg3, arg4,

                                       arg5, arg6, arg7, arg8, arg9);

  return result;

}

}  // namespace strings

#endif // YB_GUTIL_STRINGS_SUBSTITUTE_H