1/* Copyright 2017 The TensorFlow Authors. All Rights Reserved.
2
3Licensed under the Apache License, Version 2.0 (the "License");
4you may not use this file except in compliance with the License.
5You may obtain a copy of the License at
6
7 http://www.apache.org/licenses/LICENSE-2.0
8
9Unless required by applicable law or agreed to in writing, software
10distributed under the License is distributed on an "AS IS" BASIS,
11WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12See the License for the specific language governing permissions and
13limitations under the License.
14==============================================================================*/
15// This file is used to provide equivalents of internal absl::FormatF
16// and absl::StrAppendFormat. Unfortunately, type safety is not as good as a
17// a full C++ example.
18// TODO(aselle): When absl adds support for StrFormat, use that instead.
19#ifndef TENSORFLOW_LITE_TOCO_FORMAT_PORT_H_
20#define TENSORFLOW_LITE_TOCO_FORMAT_PORT_H_
21
22#include <string>
23
24#include "tensorflow/core/lib/strings/stringprintf.h"
25#include "tensorflow/lite/toco/toco_types.h"
26
27namespace toco {
28namespace port {
29
30/// Identity (default case)
31template <class T>
32T IdentityOrConvertStringToRaw(T foo) {
33 return foo;
34}
35
36// Overloaded case where we return std::string.
37inline const char* IdentityOrConvertStringToRaw(const std::string& foo) {
38 return foo.c_str();
39}
40
41// Delegate to TensorFlow Appendf function until absl has an equivalent.
42template <typename... Args>
43inline void AppendFHelper(std::string* destination, const char* fmt,
44 Args&&... args) {
45 tensorflow::strings::Appendf(destination, fmt, args...);
46}
47
48// Specialization for no argument format string (avoid security bug).
49inline void AppendFHelper(std::string* destination, const char* fmt) {
50 tensorflow::strings::Appendf(destination, "%s", fmt);
51}
52
53// Append formatted string (with format fmt and args args) to the string
54// pointed to by destination. fmt follows C printf semantics.
55// One departure is that %s can be driven by a std::string or string.
56template <typename... Args>
57inline void AppendF(std::string* destination, const char* fmt, Args&&... args) {
58 AppendFHelper(destination, fmt, IdentityOrConvertStringToRaw(args)...);
59}
60
61// Return formatted string (with format fmt and args args). fmt follows C printf
62// semantics. One departure is that %s can be driven by a std::string or string.
63template <typename... Args>
64inline std::string StringF(const char* fmt, Args&&... args) {
65 std::string result;
66 AppendFHelper(&result, fmt, IdentityOrConvertStringToRaw(args)...);
67 return result;
68}
69
70} // namespace port
71} // namespace toco
72
73#endif // TENSORFLOW_LITE_TOCO_FORMAT_PORT_H_
74