oceanbase/tools/ob_admin/clog_tool/cmd_args_parser.h

/**
 * Copyright (c) 2021 OceanBase
 * OceanBase CE is licensed under Mulan PubL v2.
 * You can use this software according to the terms and conditions of the Mulan PubL v2.
 * You may obtain a copy of Mulan PubL v2 at:
 *          http://license.coscl.org.cn/MulanPubL-2.0
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
 * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
 * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PubL v2 for more details.
 */

#ifndef __OB_TOOLS_CMD_ARGS_PARSER_H__
#define __OB_TOOLS_CMD_ARGS_PARSER_H__
class CmdArgsParser {
  const static int64_t MAX_N_ARGS = 1 << 10;
  struct arg_t {
    arg_t() : name_(NULL), value_(null_), default_value_(NULL)
    {}
    ~arg_t()
    {}
    const char* name_;
    const char* value_;
    const char* default_value_;
  };

public:
  CmdArgsParser() : parse_seq_(0), n_args_(0)
  {
    default_arg_.name_ = "*default*";
    default_arg_.value_ = null_;
    default_arg_.default_value_ = null_;
  }
  ~CmdArgsParser()
  {}
  bool reset()
  {
    memset(args_, 0, sizeof(args_));
    n_args_ = 0;
    parse_seq_ |= 1;
    return true;
  }
  bool check(int argc, char** argv, ...)
  {
    bool args_is_valid = true;
    char* p = NULL;
    parse_seq_ = (parse_seq_ & ~1) + 2;

    for (int64_t i = 0; i < n_args_ / 2; i++) {
      arg_t arg = args_[i];
      args_[i] = args_[n_args_ - 1 - i];
      args_[n_args_ - 1 - i] = arg;
    }
    for (int64_t i = 0; i < argc; i++) {
      if (argv[i][0] == ':' || NULL == (p = strchr(argv[i], '=')))
        continue;
      *p++ = 0;
      arg_t* arg = get_arg(argv[i]);
      if (arg && &default_arg_ != arg)
        arg->value_ = p;
      *--p = '=';
    }
    for (int64_t i = 0; i < argc; i++) {
      if (argv[i][0] != ':' && (p = strchr(argv[i], '=')))
        continue;
      p = argv[i][0] == ':' ? argv[i] + 1 : argv[i];
      arg_t* arg = get_next_unset_arg();
      if (arg && arg->name_)
        arg->value_ = p;
    }
    for (int64_t i = 0; i < n_args_; i++) {
      if (null_ == args_[i].value_ && args_[i].default_value_)
        args_[i].value_ = args_[i].default_value_;
      if (null_ == args_[i].value_)
        args_is_valid = false;
    }
    if (0 == strcmp("true", getenv("dump_args") ?: "false")) {
      dump(argc, argv);
    }
    return args_is_valid;
  }

  void dump(int argc, char** argv)
  {
    printf("cmd_args_parser.dump:\n");
    for (int64_t i = 0; i < argc; i++) {
      printf("argv[%ld]=%s\n", i, argv[i]);
    }
    for (int64_t i = 0; i < n_args_; i++) {
      printf(
          "args[%ld]={name=%s, value=%s, default=%s}\n", i, args_[i].name_, args_[i].value_, args_[i].default_value_);
    }
  }

  arg_t* get_next_unset_arg()
  {
    for (int64_t i = 0; i < n_args_; i++) {
      if (null_ == args_[i].value_)
        return args_ + i;
    }
    return NULL;
  }

  arg_t* get_arg(const char* name, const char* default_value = NULL)
  {
    assert(n_args_ < MAX_N_ARGS && name);
    if (parse_seq_ & 1) {
      args_[n_args_].name_ = name;
      args_[n_args_].default_value_ = default_value;
      args_[n_args_].value_ = null_;
      return args_ + (n_args_++);
    }
    for (int64_t i = 0; i < n_args_; i++) {
      if (0 == strcmp(args_[i].name_, name))
        return args_ + i;
    }
    return &default_arg_;
  }

private:
  static const char* null_;
  int64_t parse_seq_;
  int64_t n_args_;
  arg_t default_arg_;
  arg_t args_[MAX_N_ARGS];
};
inline bool argv1_match_func(const char* argv1, const char* func)
{
  const char* last_part = strrchr(func, '.');
  if (NULL != last_part) {
    last_part++;
  } else {
    last_part = func;
  }
  return 0 == strcmp(last_part, argv1);
}

const char* CmdArgsParser::null_ __attribute__((weak)) = "*null*";
CmdArgsParser __cmd_args_parser __attribute__((weak));
#define _Arg(name, ...) __cmd_args_parser.get_arg(#name, ##__VA_ARGS__)
#define BoolArg(name, ...) (0 == atoll(__cmd_args_parser.get_arg(#name, ##__VA_ARGS__)->value_)) ? true : false
#define IntArg(name, ...) atoll(__cmd_args_parser.get_arg(#name, ##__VA_ARGS__)->value_)
#define StrArg(name, ...) __cmd_args_parser.get_arg(#name, ##__VA_ARGS__)->value_
#define CmdCall(argc, argv, func, ...)                                           \
  (argc >= 2 && argv1_match_func(argv[1], #func) && __cmd_args_parser.reset() && \
      __cmd_args_parser.check(argc - 2, argv + 2, ##__VA_ARGS__))                \
      ? func(__VA_ARGS__)

#define CmdCallSimple(argc, argv, func) (argc >= 3 && argv1_match_func(argv[1], #func)) ? func(argc - 2, argv + 2)
#endif /* __OB_TOOLS_CMD_ARGS_PARSER_H__ */