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Use pipe to properly block clients when server hasn't entered event loop. #1541
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server hasn't entered event loop.
congwang
reviewed
Nov 8, 2016
| ::usleep(1000); | ||
| // choose an arbitrary number for ``sent'' as token | ||
| int recv, sent = 19583; | ||
| if (pipe(fds) < 0) { |
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resolved via 0238865
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| // block clients from reading from server using pipe | ||
| read(fds[0], &recv, sizeof(int)); | ||
| if (recv != sent) { |
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No need to check the value, we only have one reader and one writer.
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resolved via 593f35a
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Good one! Thanks for fixing this. |
congwang
reviewed
Nov 8, 2016
| @@ -35,7 +36,7 @@ static const sp_uint32 SERVER_PORT = 60000; | |||
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| extern void start_http_client(sp_uint32 _port, sp_uint64 _requests, sp_uint32 _nkeys); | |||
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| extern void start_http_server(sp_uint32 _port, sp_uint32 _nkeys); | |||
| extern void start_http_server(sp_uint32 _port, sp_uint32 _nkeys, int fd, int sent); | |||
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'sent' is no longer needed either.
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resolved via dc18567
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Looks good to me. |
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Should fix #1544. |
nicknezis
pushed a commit
that referenced
this pull request
Sep 14, 2020
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The previous way of using
usleepcannot guarantee the clients are blocked when server hasn't entered event loop, which makesheron/common/tests/cpp/network:http_unittestflaky.This PR switches to using pipe. Server will send a byte to pipe prior to entering event loop. Clients will wait(block) until the byte is read on the other side of the pipe. This makes sure that clients are properly blocked.
Test done via script
Thanks @congwang for suggestions.