guard against throwing in random_access_file's write_datastream dtor
#439
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greg7mdp
reviewed
Jul 30, 2024
| @@ -419,12 +433,14 @@ class random_access_file { | |||
| void pack_to(const T& v, const ssize_t offset) { | |||
| write_datastream ds(ctx, offset); | |||
| fc::raw::pack(ds, v); | |||
| ds.flush(); | |||
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Could the ctx->write_to() on each pack_to() call hurt performance?
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Not in this case: the buffer is/was flushed upon destruction of write_datastream so the buffer was already being flushed at the end of pack_to().
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Note:start |
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An alternative might be to actually allow |
heifner
approved these changes
Aug 8, 2024
greg7mdp
approved these changes
Aug 8, 2024
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I encountered an unfortunate design deficiency in
random_access_file'swrite_datastream. Upon destructionwrite_datastreamwill flush its buffer viado_write()but that call can throw. When this occurs obviously it's Game Over.This tweaks the interface to
write_datastream: exceptions during dtor are swallowed (with a log warning); if a user of the class wants errors to be reported they must call a newflush()which still throws if writing the buffer fails.I don't really like that and I'm open to other potential tweaks, but this pattern does have some precedent in
ofstream(withbasic_filebuf).