EVOLUTION-MANAGER

Edit File: parse_flags_from_env.h

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you may not use this file except in compliance with the License.
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==============================================================================*/

#ifndef TENSORFLOW_COMPILER_XLA_PARSE_FLAGS_FROM_ENV_H_
#define TENSORFLOW_COMPILER_XLA_PARSE_FLAGS_FROM_ENV_H_

// This module exports ParseFlagsFromEnvAndDieIfUnknown(), which allows other
// modules to parse flags from an environtment variable, or (if the first
// non-whitespace in the variable value is not '-'), a file named by that
// environment variable.
//
// The accepted syntax is that flags arguments are of the form --flag=value or
// (for boolean flags) --flag, and are whitespace separated.  The <value> may be
// one of:
//
//  - <non-whitespace, non-nul not starting with single-quote or double-quote>
//    in which case the effective value is the string itself
//  - <single-quote><characters string not containing nul or
//    single-quote><single_quote> in which case the effective value is the
//    string with the single-quotes removed
//  - <double-quote><character string not containing nul or unescaped
//    double-quote><double_quote> in which case the effective value if the
//    string with the double-quotes removed, and escaped sequences of
//    <backslash><char> replaced by <char>.
//
// Flags values inconsistent with the type of the flag will be rejected by the
// flag parser.
//
// Examples:
//
//  - TF_XLA_FLAGS="--foo=bar  --wombat='value with a space'"
//  - TF_XLA_FLAGS=/tmp/flagfile
//
// where /tmp/flagfile might contain
//
//  --some_flag="This is a string containing a \" and a '."
//  --another_flag=wombats

#include <vector>

#include "absl/strings/string_view.h"
#include "tensorflow/compiler/xla/types.h"
#include "tensorflow/core/platform/types.h"
#include "tensorflow/core/util/command_line_flags.h"

namespace xla {

// Calls tensorflow::Flags::Parse(argc, argv, flag_list) against any as yet
// unrecognized flags passed in the environment variable `envvar`, and returns
// its return value.
//
// Raises a fatal error if any flags in `envvar` were not recognized.
bool ParseFlagsFromEnvAndDieIfUnknown(
    absl::string_view envvar, const std::vector<tensorflow::Flag>& flag_list);

// Used only for testing.  Not to be used by clients.
void ResetFlagsFromEnvForTesting(absl::string_view envvar, int** pargc,
                                 std::vector<char*>** pargv);

}  // namespace xla

#endif  // TENSORFLOW_COMPILER_XLA_PARSE_FLAGS_FROM_ENV_H_