at_exit

Transcript

1. at_exit {}
   2019-07-20 Nagano.rb #2
   @bgpat
   

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2. @bgpat / Atsushi Tanaka
   Infrastructure Engineer at Wantedly, Inc.
   

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3. ऴྃॲཧɺ࢖ͬͯ·͔͢ʁ
   

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4. ऴྃॲཧɺ࢖ͬͯ·͔͢ʁ
   ऴྃॲཧϓϩάϥϜ͕ऴྃ͢Δͱ͖ʹ࣮ߦ͞ΕΔॲཧ
   

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5. fluent-logger
   

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6. lib/fluent/logger/fluent_logger.rb
   class FluentLogger < LoggerBase
   ộ
   def initialize(tag_prefix = nil, *args)
   super()
   ộ
   at_exit { close }
   end
   ộ
   def close
   @mon.synchronize {
   if @pending
   begin
   send_data(@pending)
   rescue => e
   set_last_error(e)
   @logger.error("FluentLogger: Can't send logs to #{connection_string}: #{$!}")
   call_buffer_overflow_handler(@pending)
   end
   end
   @con.close if connect?
   @con = nil
   @pending = nil
   }
   self
   end
   ộ
   

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7. lib/fluent/logger/fluent_logger.rb
   class FluentLogger < LoggerBase
   ộ
   def initialize(tag_prefix = nil, *args)
   super()
   ộ
   at_exit { close }
   end
   ộ
   def close
   @mon.synchronize {
   if @pending
   begin
   send_data(@pending)
   rescue => e
   set_last_error(e)
   @logger.error("FluentLogger: Can't send logs to #{connection_string}: #{$!}")
   call_buffer_overflow_handler(@pending)
   end
   end
   @con.close if connect?
   @con = nil
   @pending = nil
   }
   self
   end
   ộ
   MPHHFSͷॳظԽ
   

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8. lib/fluent/logger/fluent_logger.rb
   class FluentLogger < LoggerBase
   ộ
   def initialize(tag_prefix = nil, *args)
   super()
   ộ
   at_exit { close }
   end
   ộ
   def close
   @mon.synchronize {
   if @pending
   begin
   send_data(@pending)
   rescue => e
   set_last_error(e)
   @logger.error("FluentLogger: Can't send logs to #{connection_string}: #{$!}")
   call_buffer_overflow_handler(@pending)
   end
   end
   @con.close if connect?
   @con = nil
   @pending = nil
   }
   self
   end
   ộ
   ऴྃॲཧͷొ࿥
   

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9. lib/fluent/logger/fluent_logger.rb
   class FluentLogger < LoggerBase
   ộ
   def initialize(tag_prefix = nil, *args)
   super()
   ộ
   at_exit { close }
   end
   ộ
   def close
   @mon.synchronize {
   if @pending
   begin
   send_data(@pending)
   rescue => e
   set_last_error(e)
   @logger.error("FluentLogger: Can't send logs to #{connection_string}: #{$!}")
   call_buffer_overflow_handler(@pending)
   end
   end
   @con.close if connect?
   @con = nil
   @pending = nil
   }
   self
   end
   ộ
   ऴྃॲཧ
   

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10. lib/fluent/logger/fluent_logger.rb
    class FluentLogger < LoggerBase
    ộ
    def initialize(tag_prefix = nil, *args)
    super()
    ộ
    at_exit { close }
    end
    ộ
    def close
    @mon.synchronize {
    if @pending
    begin
    send_data(@pending)
    rescue => e
    set_last_error(e)
    @logger.error("FluentLogger: Can't send logs to #{connection_string}: #{$!}")
    call_buffer_overflow_handler(@pending)
    end
    end
    @con.close if connect?
    @con = nil
    @pending = nil
    }
    self
    end
    ộ
    ະॲཧͷϩάΛૹ৴͠ऴΘΔ·Ͱ଴ͭ
    

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11. Ruby on Rails
    (Active Record)
    

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12. activerecord/lib/active_record/railties/console_sandbox.rb
    # frozen_string_literal: true
    ActiveRecord::Base.connection.begin_transaction(joinable: false)
    at_exit do
    ActiveRecord::Base.connection.rollback_transaction
    end
    

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13. activerecord/lib/active_record/railties/console_sandbox.rb
    # frozen_string_literal: true
    ActiveRecord::Base.connection.begin_transaction(joinable: false)
    at_exit do
    ActiveRecord::Base.connection.rollback_transaction
    end
    τϥϯβΫγϣϯதʹऴྃͨ͠Β

    ϩʔϧόοΫ͢Δ
    

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14. at_exit{}Λ࢖͏ͱ
    
    ϓϩάϥϜऴྃ࣌ͷॲཧΛ
    ొ࿥Ͱ͖Δ
    

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15. eval_jump.c
    static VALUE
    rb_f_at_exit(void)
    {
    VALUE proc;
    if (!rb_block_given_p()) {
    rb_raise(rb_eArgError, "called without a block");
    }
    proc = rb_block_proc();
    rb_set_end_proc(rb_call_end_proc, proc);
    return proc;
    }
    void
    Init_jump(void)
    {
    rb_define_global_function("at_exit", rb_f_at_exit, 0);
    }
    

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16. eval_jump.c
    static VALUE
    rb_f_at_exit(void)
    {
    VALUE proc;
    if (!rb_block_given_p()) {
    rb_raise(rb_eArgError, "called without a block");
    }
    proc = rb_block_proc();
    rb_set_end_proc(rb_call_end_proc, proc);
    return proc;
    }
    void
    Init_jump(void)
    {
    rb_define_global_function("at_exit", rb_f_at_exit, 0);
    }
    at_exitͷఆٛ
    

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17. eval_jump.c
    static VALUE
    rb_f_at_exit(void)
    {
    VALUE proc;
    if (!rb_block_given_p()) {
    rb_raise(rb_eArgError, "called without a block");
    }
    proc = rb_block_proc();
    rb_set_end_proc(rb_call_end_proc, proc);
    return proc;
    }
    void
    Init_jump(void)
    {
    rb_define_global_function("at_exit", rb_f_at_exit, 0);
    }
    ϒϩοΫͷొ࿥
    

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18. eval_jump.c
    void
    rb_set_end_proc(void (*func)(VALUE), VALUE data)
    {
    struct end_proc_data *link = ALLOC(struct
    end_proc_data);
    struct end_proc_data **list;
    rb_thread_t *th = GET_THREAD();
    if (th->top_wrapper) {
    list = &ephemeral_end_procs;
    }
    else {
    list = &end_procs;
    }
    link->next = *list;
    link->func = func;
    link->data = data;
    *list = link;
    }
    

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19. eval_jump.c
    void
    rb_set_end_proc(void (*func)(VALUE), VALUE data)
    {
    struct end_proc_data *link = ALLOC(struct
    end_proc_data);
    struct end_proc_data **list;
    rb_thread_t *th = GET_THREAD();
    if (th->top_wrapper) {
    list = &ephemeral_end_procs;
    }
    else {
    list = &end_procs;
    }
    link->next = *list;
    link->func = func;
    link->data = data;
    *list = link;
    }
    Ϧετͷઌ಄ʹ௥Ճ
    

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20. ࣮͸ऴྃॲཧͷղઆ͕͋Δ
    

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21. ਖ਼ৗऴྃͷ৔߹Λ௥ͬͯΈΔ
    

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22. main.c
    int
    main(int argc, char **argv)
    {
    #ifdef RUBY_DEBUG_ENV
    ruby_set_debug_option(getenv("RUBY_DEBUG"));
    #endif
    #ifdef HAVE_LOCALE_H
    setlocale(LC_CTYPE, "");
    #endif
    ruby_sysinit(&argc, &argv);
    {
    RUBY_INIT_STACK;
    ruby_init();
    return ruby_run_node(ruby_options(argc, argv));
    }
    }
    

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23. main.c
    int
    main(int argc, char **argv)
    {
    #ifdef RUBY_DEBUG_ENV
    ruby_set_debug_option(getenv("RUBY_DEBUG"));
    #endif
    #ifdef HAVE_LOCALE_H
    setlocale(LC_CTYPE, "");
    #endif
    ruby_sysinit(&argc, &argv);
    {
    RUBY_INIT_STACK;
    ruby_init();
    return ruby_run_node(ruby_options(argc, argv));
    }
    }
    εΫϦϓτΛ࣮ߦ
    

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24. eval.c
    /*! Runs the given compiled source and exits this process.
    * @retval 0 if successfully run the source
    * @retval non-zero if an error occurred.
    */
    int
    ruby_run_node(void *n)
    {
    int status;
    if (!ruby_executable_node(n, &status)) {
    ruby_cleanup(0);
    return status;
    }
    return ruby_cleanup(ruby_exec_node(n));
    }
    

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25. eval.c
    /*! Runs the given compiled source and exits this process.
    * @retval 0 if successfully run the source
    * @retval non-zero if an error occurred.
    */
    int
    ruby_run_node(void *n)
    {
    int status;
    if (!ruby_executable_node(n, &status)) {
    ruby_cleanup(0);
    return status;
    }
    return ruby_cleanup(ruby_exec_node(n));
    }
    ॲཧͷ࣮ମ
    

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26. eval.c
    /*! Runs the given compiled source and exits this process.
    * @retval 0 if successfully run the source
    * @retval non-zero if an error occurred.
    */
    int
    ruby_run_node(void *n)
    {
    int status;
    if (!ruby_executable_node(n, &status)) {
    ruby_cleanup(0);
    return status;
    }
    return ruby_cleanup(ruby_exec_node(n));
    }
    εΫϦϓτͷऴ୺ʹୡͨ͠
    

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27. eval.c
    /** Destructs the VM.
    *
    * Runs the VM finalization processes as well as ruby_finalize(), and
    * resources used by the VM.
    *
    * @param ex Default value to the return value.
    * @return If an error occurred returns a non-zero. If otherwise, retur
    * given ex.
    * @note This function does not raise any exception.
    */
    int
    ruby_cleanup(volatile int ex)
    {
    int state;
    ộ
    SAVE_ROOT_JMPBUF(th, ruby_finalize_0());
    ộ
    ruby_finalize_1();
    ộ
    return sysex;
    }
    

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28. eval.c
    /** Destructs the VM.
    *
    * Runs the VM finalization processes as well as ruby_finalize(), and
    * resources used by the VM.
    *
    * @param ex Default value to the return value.
    * @return If an error occurred returns a non-zero. If otherwise, retur
    * given ex.
    * @note This function does not raise any exception.
    */
    int
    ruby_cleanup(volatile int ex)
    {
    int state;
    ộ
    SAVE_ROOT_JMPBUF(th, ruby_finalize_0());
    ộ
    ruby_finalize_1();
    ộ
    return sysex;
    }
    ऴྃ࣌ͷϑοΫͷ࣮ߦ
    

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29. eval.c
    static void
    ruby_finalize_0(void)
    {
    EC_PUSH_TAG(GET_EC());
    if (EC_EXEC_TAG() == TAG_NONE) {
    rb_trap_exit();
    }
    EC_POP_TAG();
    rb_exec_end_proc();
    rb_clear_trace_func();
    }
    

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30. eval.c
    static void
    ruby_finalize_0(void)
    {
    EC_PUSH_TAG(GET_EC());
    if (EC_EXEC_TAG() == TAG_NONE) {
    rb_trap_exit();
    }
    EC_POP_TAG();
    rb_exec_end_proc();
    rb_clear_trace_func();
    }
    

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31. eval_jump.c
    void
    rb_exec_end_proc(void)
    {
    enum ruby_tag_type state;
    rb_execution_context_t * volatile ec = GET_EC();
    volatile VALUE errinfo = ec->errinfo;
    EC_PUSH_TAG(ec);
    if ((state = EC_EXEC_TAG()) == TAG_NONE) {
    again:
    exec_end_procs_chain(&ephemeral_end_procs, &ec->errinfo);
    exec_end_procs_chain(&end_procs, &ec->errinfo);
    }
    else {
    EC_TMPPOP_TAG();
    error_handle(state);
    if (!NIL_P(ec->errinfo)) errinfo = ec->errinfo;
    EC_REPUSH_TAG();
    goto again;
    

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32. eval_jump.c
    void
    rb_exec_end_proc(void)
    {
    enum ruby_tag_type state;
    rb_execution_context_t * volatile ec = GET_EC();
    volatile VALUE errinfo = ec->errinfo;
    EC_PUSH_TAG(ec);
    if ((state = EC_EXEC_TAG()) == TAG_NONE) {
    again:
    exec_end_procs_chain(&ephemeral_end_procs, &ec->errinfo);
    exec_end_procs_chain(&end_procs, &ec->errinfo);
    }
    else {
    EC_TMPPOP_TAG();
    error_handle(state);
    if (!NIL_P(ec->errinfo)) errinfo = ec->errinfo;
    EC_REPUSH_TAG();
    goto again;
    BU@FYJUͰొ࿥ͨ͠

    ϒϩοΫΛ࣮ߦ
    

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33. eval_jump.c
    static void
    exec_end_procs_chain(struct end_proc_data *volatile
    *procs, VALUE *errp)
    {
    struct end_proc_data volatile endproc;
    struct end_proc_data *link;
    VALUE errinfo = *errp;
    while ((link = *procs) != 0) {
    *procs = link->next;
    endproc = *link;
    xfree(link);
    (*endproc.func) (endproc.data);
    *errp = errinfo;
    }
    }
    

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34. eval_jump.c
    static void
    exec_end_procs_chain(struct end_proc_data *volatile
    *procs, VALUE *errp)
    {
    struct end_proc_data volatile endproc;
    struct end_proc_data *link;
    VALUE errinfo = *errp;
    while ((link = *procs) != 0) {
    *procs = link->next;
    endproc = *link;
    xfree(link);
    (*endproc.func) (endproc.data);
    *errp = errinfo;
    }
    }
    ϦετΛઌ಄͔Βॱ൪ʹ࣮ߦ

    ʢat_exitΛݺͼग़ͨ͠ͷͱٯॱʹ࣮ߦʣ
    

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35. ྫ֎ൃੜͷ৔߹Λ௥ͬͯΈΔ
    

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36. process.c
    VALUE
    rb_f_exit(int argc, const VALUE *argv)
    {
    int istatus;
    if (rb_check_arity(argc, 0, 1) == 1) {
    istatus = exit_status_code(argv[0]);
    }
    else {
    istatus = EXIT_SUCCESS;
    }
    rb_exit(istatus);
    UNREACHABLE_RETURN(Qnil);
    }

    

    rb_define_global_function("exit", rb_f_exit, -1);
    

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37. process.c
    VALUE
    rb_f_exit(int argc, const VALUE *argv)
    {
    int istatus;
    if (rb_check_arity(argc, 0, 1) == 1) {
    istatus = exit_status_code(argv[0]);
    }
    else {
    istatus = EXIT_SUCCESS;
    }
    rb_exit(istatus);
    UNREACHABLE_RETURN(Qnil);
    }

    

    rb_define_global_function("exit", rb_f_exit, -1);
    Kernel.exitͷఆٛ
    

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38. process.c
    VALUE
    rb_f_exit(int argc, const VALUE *argv)
    {
    int istatus;
    if (rb_check_arity(argc, 0, 1) == 1) {
    istatus = exit_status_code(argv[0]);
    }
    else {
    istatus = EXIT_SUCCESS;
    }
    rb_exit(istatus);
    UNREACHABLE_RETURN(Qnil);
    }

    

    rb_define_global_function("exit", rb_f_exit, -1);
    ॲཧͷதஅ
    

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39. process.c
    void
    rb_exit(int status)
    {
    if (GET_EC()->tag) {
    VALUE args[2];
    args[0] = INT2NUM(status);
    args[1] = rb_str_new2("exit");
    rb_exc_raise(rb_class_new_instance(2, args,
    rb_eSystemExit));
    }
    ruby_stop(status);
    }
    

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40. process.c
    void
    rb_exit(int status)
    {
    if (GET_EC()->tag) {
    VALUE args[2];
    args[0] = INT2NUM(status);
    args[1] = rb_str_new2("exit");
    rb_exc_raise(rb_class_new_instance(2, args,
    rb_eSystemExit));
    }
    ruby_stop(status);
    }
    

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41. eval.c
    /*! Calls ruby_cleanup() and exits the process */
    void
    ruby_stop(int ex)
    {
    exit(ruby_cleanup(ex));
    }
    

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42. eval.c
    /*! Calls ruby_cleanup() and exits the process */
    void
    ruby_stop(int ex)
    {
    exit(ruby_cleanup(ex));
    }
    ͖ͬ͞ݟͨ
    

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43. ·ͱΊ
    w Rubyͷऴྃ࣌ʹԿ͔࣮ߦ͢ΔͳΒat_exit Λ࢖͏
    w at_exit ʹ౉ͨ͠ϒϩοΫ͸ยํ޲ϦετʹೖΔ
    ઌ಄͔ΒೖΕͯઌ಄͔Βॱʹ࣮ߦ
    w Rubyͷιʔείʔυ͸ҙ֎ͱಡΊΔ
    ΄ͱΜͲ$ݴޠ͚ͩͲ؆୯
    

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44. ͓·͚
    ͕࣌ؒ͋Ε͹
    

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45. END΋࢖͑Δ
    

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46. https://docs.google.com/document/d/
    1CGHMFHkqww2pAnbVJo8p9TtGv3Ng15EKYGvRIcnwMA
    o/edit?usp=sharing
    

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