curses-based rule progress indicator

[caitp]

I'm in a situation where a build depends on some autoconf submodules, and configure / make are essentially their own rules. Naturally, these can take a fairly lengthy amount of time. Unfortunately, ninja doesn't seem to write any output until the rule ends, so it sort of looks like the build is hanging.

As a compromise, I think it would be a good plan to output some sort of "work in progress" indicator during each rule, so that it's clear that a hang is not occurring. Even better, it would be good to write the full output of the child process to the terminal, and just keeping the pretty display in the bottom line, similar to the Mozilla mach/pymake builds.

Thoughts? Feelings? Valid concern?

[nico]

The current thinking is to add a "console" pool that can provide immediate output, see #714.

(There used to be some progress printing code that I removed in 555431a as it was dead due to a pointer dereference bug. Maybe you can try reverting that locally, and make it say int total_time = *end_time - *start_time; to make it work.)