WIP: VMSplice/STDOUT consumer

[tempusfrangit]

No description provided.

[tempusfrangit]

@technillogue see if this works for you, we should generally order the requests for slices.

io.copy also handles backpressure from full pipes elegantly (AFAICT). We also do have a greedy reader to capture wire data even if the consumer is blocking.

[tempusfrangit]

Suggested change

	{{ .ProjectName }}_{{ tolower .Os }}_
	{{ .ProjectName }}_{{ title .Os }}_

[tempusfrangit]

this was not an intended change.

[technillogue]

this could definitely work! would it work with multifile and writing multiple files to stdout in order?

[tempusfrangit]

We can make that happen! Wouldn't be too hard. This was a first pass to see if it looked good.

[tempusfrangit]

It turns out the only reason we don't order downloads which causes you the problem is a historical reason for using a map instead of a list.

Additionally there is the maximum concurrent files option already that could limit concurrency -- additionally we can set it to automatically use a max file concurrency of one for stdout/vmsplice modes.

[technillogue]

how would I invoke this? (edit: -o stdout)

[tempusfrangit]

@technillogue Rebased. Download order is now guaranteed. You will want to make sure to use --max-concurrent-files=1 and -o stdout or -o vmsplice

Please let me know if this works. if so we can easily spin up this output consumer.

[technillogue]

this doesn't build

Error: pkg/consumer/linux_vmsplice.go:15:18: cannot use &VMSpliceConsumer{} (value of type *VMSpliceConsumer) as Consumer value in variable declaration: *VMSpliceConsumer does not implement Consumer (wrong type for method Consume)
		have Consume(io.Reader, string, int64) error
		want Consume(io.Reader, string) error
Error: pkg/consumer/stdout.go:9:18: cannot use &StdoutConsumer{} (value of type *StdoutConsumer) as Consumer value in variable declaration: *StdoutConsumer does not implement Consumer (wrong type for method Consume)
		have Consume(io.Reader, string, int64) error
		want Consume(io.Reader, string) error