Annotate

net/resolvers/chain.lua @ 13461:c673ff1075bd

mod_posix: Move everything to util.startup This allows greater control over the order of events. Notably, the internal ordering between daemonization, initialization of libunbound and setup of signal handling is sensitive. libunbound starts a separate thread for processing DNS requests. If this thread is started before signal handling has been set up, it will not inherit the signal handlers and instead behave as it would have before signal handlers were set up, i.e. cause the whole process to immediately exit. libunbound is usually initialized on the first DNS request, usually triggered by an outgoing s2s connection attempt. If daemonization happens before signals have been set up, signals may not be processed at all.
author Kim Alvefur <zash@zash.se>
date Sat, 23 Mar 2024 20:48:19 +0100
parent 12204:7c397a49d163
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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12204
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
Kim Alvefur <zash@zash.se>
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1
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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2 local methods = {};
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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3 local resolver_mt = { __index = methods };
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4
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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5 -- Find the next target to connect to, and
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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6 -- pass it to cb()
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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7 function methods:next(cb)
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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8 if self.resolvers then
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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9 if not self.resolver then
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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10 if #self.resolvers == 0 then
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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11 cb(nil);
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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12 return;
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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13 end
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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14 local next_resolver = table.remove(self.resolvers, 1);
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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15 self.resolver = next_resolver;
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16 end
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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17 self.resolver:next(function (...)
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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18 if self.resolver then
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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19 self.last_error = self.resolver.last_error;
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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20 end
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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21 if ... == nil then
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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22 self.resolver = nil;
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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23 self:next(cb);
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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24 else
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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25 cb(...);
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26 end
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27 end);
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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28 return;
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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29 end
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30 end
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31
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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32 local function new(resolvers)
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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33 return setmetatable({ resolvers = resolvers }, resolver_mt);
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34 end
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35
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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36 return {
7c397a49d163 net.resolvers.chain: A resolver for combining other resolvers
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37 new = new;
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38 };