Rewrite the Command API

Important: the simplified API now defaults to forwarding interrupts to
subprocesses. I did audit all the call sites, and I think this is a safe change
to make.

- Properly support timeouts with all implementations
- Simplify the API
  - only provide two flavours of blocking calls, which require no input and
    forward interrupts; this is the most common usage
  - provide a number of async calls, which optionally takes input, and a flag
    whether to forward interrupts
  - only support input streams, no byte arrays or other 'convenience features'
    that are rarely needed and unnecessarily increase the surface area
  - use java.time.Duration to specify timeout; for consistency, interpret a
    timeout of <= 0 as no timeout (i.e., including rather than excluding 0)
  - KillableObserver and subclasses are no longer part of the public API, but
    still used to implement timeouts if the Subprocess.Factory does not support
    them
- Update the documentation for Command
- Update all callers; most callers now use the simplified API

PiperOrigin-RevId: 164716782

1 files changed, 4 insertions, 9 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/runtime/mobileinstall/MobileInstallCommand.java b/src/main/java/com/google/devtools/build/lib/runtime/mobileinstall/MobileInstallCommand.java
index ab909d025f..8a83400c63 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/mobileinstall/MobileInstallCommand.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/mobileinstall/MobileInstallCommand.java
@@ -264,16 +264,11 @@ public class MobileInstallCommand implements BlazeCommand {
       // actual output of the command being run even if --color=no is specified.
       env.getReporter().switchToAnsiAllowingHandler();
 
-      // The command API is a little strange in that the following statement
-      // will return normally only if the program exits with exit code 0.
-      // If it ends with any other code, we have to catch BadExitStatusException.
+      // The command API is a little strange in that the following statement will return normally
+      // only if the program exits with exit code 0. If it ends with any other code, we have to
+      // catch BadExitStatusException.
       command
-          .execute(
-              com.google.devtools.build.lib.shell.Command.NO_INPUT,
-              com.google.devtools.build.lib.shell.Command.NO_OBSERVER,
-              outErr.getOutputStream(),
-              outErr.getErrorStream(),
-              true /* interruptible */)
+          .execute(outErr.getOutputStream(), outErr.getErrorStream())
           .getTerminationStatus()
           .getExitCode();
       return ExitCode.SUCCESS;