zmake: Write ninja output to a build.log file

In order to capture the memory usage report in the link stage, write all
output from ninja to a build.log file in the build dir.

For example:
`zmake build herobrine` will create files in
`build/zephyr/herobrine/build-ro/build.log` and
`build/zephyr/herobrine/build-rw/build.log`

I intend to parse this file in firmware_builder.py

BRANCH=None
BUG=b:223846977
TEST=zmake build herobrine; \
tail build/zephyr/herobrine/build-*/build.log

Change-Id: I10e1e29e945f86bbc19adf62946ea7f3aab8fc6f
Signed-off-by: Jeremy Bettis <jbettis@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3523395
Tested-by: Jeremy Bettis <jbettis@chromium.org>
Auto-Submit: Jeremy Bettis <jbettis@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Commit-Queue: Jack Rosenthal <jrosenth@chromium.org>

2 files changed, 31 insertions, 5 deletions

diff --git a/zephyr/zmake/zmake/multiproc.py b/zephyr/zmake/zmake/multiproc.py
index 5e98374c8c..94f5f5b69d 100644
--- a/zephyr/zmake/zmake/multiproc.py
+++ b/zephyr/zmake/zmake/multiproc.py
@@ -53,7 +53,13 @@ class LogWriter:
     """
 
     def __init__(
-        self, logger, log_level, log_level_override_func, job_id, file_descriptor
+        self,
+        logger,
+        log_level,
+        log_level_override_func,
+        job_id,
+        file_descriptor,
+        tee_output=None,
     ):
         self._logger = logger
         self._log_level = log_level
@@ -62,6 +68,7 @@ class LogWriter:
         self._written_at_level = collections.defaultdict(lambda: False)
         self._job_id = job_id
         self._file_descriptor = file_descriptor
+        self._tee_output = tee_output
 
     def log_line(self, line):
         """Log a line of output
@@ -72,6 +79,9 @@ class LogWriter:
         Args:
             line: Text line to log
         """
+        if self._tee_output:
+            self._tee_output.write(line)
+            self._tee_output.write("\n")
         if self._override_func:
             # Get the new log level and update the default. The reason we
             # want to update the default is that if we hit an error, all
@@ -103,6 +113,9 @@ class LogWriter:
         """
         with _logging_cv:
             _logging_cv.wait_for(lambda: self._file_descriptor not in _logging_map)
+        if self._tee_output:
+            self._tee_output.close()
+            self._tee_output = None
 
 
 def _log_fd(fd):
@@ -182,7 +195,12 @@ _logging_thread = None
 
 
 def log_output(
-    logger, log_level, file_descriptor, log_level_override_func=None, job_id=None
+    logger,
+    log_level,
+    file_descriptor,
+    log_level_override_func=None,
+    job_id=None,
+    tee_output=None,
 ):
     """Log the output from the given file descriptor.
 
@@ -205,7 +223,12 @@ def log_output(
             _logging_thread.start()
 
         writer = LogWriter(
-            logger, log_level, log_level_override_func, job_id, file_descriptor
+            logger,
+            log_level,
+            log_level_override_func,
+            job_id,
+            file_descriptor,
+            tee_output=tee_output,
         )
         _logging_map[file_descriptor] = writer
         # Write a dummy byte to the pipe to break the select so we can add the
diff --git a/zephyr/zmake/zmake/zmake.py b/zephyr/zmake/zmake/zmake.py
index e2ce065740..11248b092e 100644
--- a/zephyr/zmake/zmake/zmake.py
+++ b/zephyr/zmake/zmake/zmake.py
@@ -11,7 +11,7 @@ import pathlib
 import re
 import shutil
 import subprocess
-from typing import List
+from typing import Dict, List
 
 import zmake.build_config
 import zmake.generate_readme
@@ -622,7 +622,7 @@ class Zmake:
 
         procs = []
         log_writers = []
-        dirs = {}
+        dirs: Dict[str, pathlib.Path] = {}
 
         build_dir = build_dir.resolve()
 
@@ -667,12 +667,15 @@ class Zmake:
                     errors="replace",
                 )
                 job_id = "{}:{}".format(project.config.project_name, build_name)
+                dirs[build_name].mkdir(parents=True, exist_ok=True)
+                build_log = open(dirs[build_name] / "build.log", "w")
                 out = zmake.multiproc.log_output(
                     logger=self.logger,
                     log_level=logging.INFO,
                     file_descriptor=proc.stdout,
                     log_level_override_func=ninja_stdout_log_level_override,
                     job_id=job_id,
+                    tee_output=build_log,
                 )
                 err = zmake.multiproc.log_output(
                     self.logger,