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The C and C++ Include Header Files

cat -n /usr/include/wabt/string-format.h

     1	/*
     2	 * Copyright 2021 WebAssembly Community Group participants
     3	 *
     4	 * Licensed under the Apache License, Version 2.0 (the "License");
     5	 * you may not use this file except in compliance with the License.
     6	 * You may obtain a copy of the License at
     7	 *
     8	 *     http://www.apache.org/licenses/LICENSE-2.0
     9	 *
    10	 * Unless required by applicable law or agreed to in writing, software
    11	 * distributed under the License is distributed on an "AS IS" BASIS,
    12	 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13	 * See the License for the specific language governing permissions and
    14	 * limitations under the License.
    15	 */
    16	
    17	#ifndef WABT_STRING_FORMAT_H_
    18	#define WABT_STRING_FORMAT_H_
    19	
    20	#include <cstdarg>
    21	#include <string>
    22	#include <vector>
    23	
    24	#include "wabt/config.h"
    25	
    26	#define PRIstringview "%.*s"
    27	#define WABT_PRINTF_STRING_VIEW_ARG(x) \
    28	  static_cast<int>((x).length()), (x).data()
    29	
    30	#define PRItypecode "%s%#x"
    31	#define WABT_PRINTF_TYPE_CODE(x) \
    32	  (static_cast<int32_t>(x) < 0 ? "-" : ""), std::abs(static_cast<int32_t>(x))
    33	
    34	#define WABT_DEFAULT_SNPRINTF_ALLOCA_BUFSIZE 128
    35	#define WABT_SNPRINTF_ALLOCA(buffer, len, format)                          \
    36	  va_list args;                                                            \
    37	  va_list args_copy;                                                       \
    38	  va_start(args, format);                                                  \
    39	  va_copy(args_copy, args);                                                \
    40	  char fixed_buf[WABT_DEFAULT_SNPRINTF_ALLOCA_BUFSIZE];                    \
    41	  char* buffer = fixed_buf;                                                \
    42	  size_t len = wabt_vsnprintf(fixed_buf, sizeof(fixed_buf), format, args); \
    43	  va_end(args);                                                            \
    44	  if (len + 1 > sizeof(fixed_buf)) {                                       \
    45	    buffer = static_cast<char*>(alloca(len + 1));                          \
    46	    len = wabt_vsnprintf(buffer, len + 1, format, args_copy);              \
    47	  }                                                                        \
    48	  va_end(args_copy)
    49	
    50	namespace wabt {
    51	
    52	inline std::string WABT_PRINTF_FORMAT(1, 2)
    53	    StringPrintf(const char* format, ...) {
    54	  va_list args;
    55	  va_list args_copy;
    56	  va_start(args, format);
    57	  va_copy(args_copy, args);
    58	  size_t len = wabt_vsnprintf(nullptr, 0, format, args) + 1;  // For \0.
    59	  std::vector<char> buffer(len);
    60	  va_end(args);
    61	  wabt_vsnprintf(buffer.data(), len, format, args_copy);
    62	  va_end(args_copy);
    63	  return std::string(buffer.data(), len - 1);
    64	}
    65	
    66	}  // namespace wabt
    67	
    68	#endif  // WABT_STRING_FORMAT_H_