freebsd-dev/contrib/kyua/bootstrap/plain_helpers.cpp

// Copyright 2010 The Kyua Authors.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
//   notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
//   notice, this list of conditions and the following disclaimer in the
//   documentation and/or other materials provided with the distribution.
// * Neither the name of Google Inc. nor the names of its contributors
//   may be used to endorse or promote products derived from this software
//   without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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#include <cstdlib>
#include <cstring>
#include <iostream>

#include "utils/defs.hpp"
#include "utils/test_utils.ipp"


namespace {


/// Prints a fake but valid test case list and then aborts.
///
/// \param argv The original arguments of the program.
///
/// \return Nothing because this dies before returning.
static int
helper_abort_test_cases_list(int /* argc */, char** argv)
{
    for (const char* const* arg = argv; *arg != NULL; arg++) {
        if (std::strcmp(*arg, "-l") == 0) {
            std::cout << "Content-Type: application/X-atf-tp; "
                "version=\"1\"\n\n";
            std::cout << "ident: foo\n";
        }
    }
    utils::abort_without_coredump();
}


/// Just returns without printing anything as the test case list.
///
/// \return Always 0, as required for test programs.
static int
helper_empty_test_cases_list(int /* argc */, char** /* argv */)
{
    return EXIT_SUCCESS;
}


/// Prints a correctly-formatted test case list but empty.
///
/// \param argv The original arguments of the program.
///
/// \return Always 0, as required for test programs.
static int
helper_zero_test_cases(int /* argc */, char** argv)
{
    for (const char* const* arg = argv; *arg != NULL; arg++) {
        if (std::strcmp(*arg, "-l") == 0)
            std::cout << "Content-Type: application/X-atf-tp; "
                "version=\"1\"\n\n";
    }
    return EXIT_SUCCESS;
}


/// Mapping of the name of a helper to its implementation.
struct helper {
    /// The name of the helper, as will be provided by the user on the CLI.
    const char* name;

    /// A pointer to the function implementing the helper.
    int (*hook)(int, char**);
};


/// NULL-terminated table mapping helper names to their implementations.
static const helper helpers[] = {
    { "abort_test_cases_list", helper_abort_test_cases_list, },
    { "empty_test_cases_list", helper_empty_test_cases_list, },
    { "zero_test_cases", helper_zero_test_cases, },
    { NULL, NULL, },
};


}  // anonymous namespace


/// Entry point to the ATF-less helpers.
///
/// The caller must select a helper to execute by defining the HELPER
/// environment variable to the name of the desired helper.  Think of this main
/// method as a subprogram dispatcher, to avoid having many individual helper
/// binaries.
///
/// \todo Maybe we should really have individual helper binaries.  It would
/// avoid a significant amount of complexity here and in the tests, at the
/// expense of some extra files and extra build logic.
///
/// \param argc The user argument count; delegated to the helper.
/// \param argv The user arguments; delegated to the helper.
///
/// \return The exit code of the helper, which depends on the requested helper.
int
main(int argc, char** argv)
{
    const char* command = std::getenv("HELPER");
    if (command == NULL) {
        std::cerr << "Usage error: HELPER must be set to a helper name\n";
        std::exit(EXIT_FAILURE);
    }

    const struct helper* iter = helpers;
    for (; iter->name != NULL && std::strcmp(iter->name, command) != 0; iter++)
        ;
    if (iter->name == NULL) {
        std::cerr << "Usage error: unknown command " << command << "\n";
        std::exit(EXIT_FAILURE);
    }

    return iter->hook(argc, argv);
}