deps: allow a --generator switch to update_deps.py

This allows you to use any CMake generator available
on your system to configure the dependent repositories,
allowing you to match the same generator being used by
the project build.

update_deps.py:
- Take a parameter to specify a CMake generator, and pass it to CMake
  if present
- Allow the user to reduce the count of parallel make jobs that can
  happen at one time
- remove an unnecessary semicolon

1 files changed, 21 insertions, 3 deletions

diff --git a/scripts/update_deps.py b/scripts/update_deps.py
index 5d00eb5b..d88cf891 100755
--- a/scripts/update_deps.py
+++ b/scripts/update_deps.py
@@ -415,6 +415,12 @@ class GoodRepo(object):
                 cmake_cmd.append('-A')
                 cmake_cmd.append('x64')
 
+        # Apply a generator, if one is specified.  This can be used to supply
+        # a specific generator for the dependent repositories to match
+        # that of the main repository.
+        if self._args.generator is not None:
+            cmake_cmd.extend(['-G', self._args.generator])
+
         if VERBOSE:
             print("CMake command: " + " ".join(cmake_cmd))
 
@@ -435,8 +441,15 @@ class GoodRepo(object):
         # Speed up the build.
         if platform.system() == 'Linux' or platform.system() == 'Darwin':
             cmake_cmd.append('--')
-            cmake_cmd.append('-j{ncpu}'
-                             .format(ncpu=multiprocessing.cpu_count()))
+            num_make_jobs = multiprocessing.cpu_count()
+            env_make_jobs = os.environ.get('MAKE_JOBS', None)
+            if env_make_jobs is not None:
+                try:
+                    num_make_jobs = min(num_make_jobs, int(env_make_jobs))
+                except ValueError:
+                    print('warning: environment variable MAKE_JOBS has non-numeric value "{}".  '
+                          'Using {} (CPU count) instead.'.format(env_make_jobs, num_make_jobs))
+            cmake_cmd.append('-j{}'.format(num_make_jobs))
         if platform.system() == 'Windows':
             cmake_cmd.append('--')
             cmake_cmd.append('/maxcpucount')
@@ -594,6 +607,11 @@ def main():
         type=str.lower,
         help="Set build files configuration",
         default='debug')
+    parser.add_argument(
+        '--generator',
+        dest='generator',
+        help="Set the CMake generator",
+        default=None)
 
     args = parser.parse_args()
     save_cwd = os.getcwd()
@@ -628,7 +646,7 @@ def main():
                       'build_platforms',
                       'repo_dir',
                       'on_build_platform')
-        repo_dict[repo.name] = {field: getattr(repo, field) for field in field_list};
+        repo_dict[repo.name] = {field: getattr(repo, field) for field in field_list}
 
         # If the repo has a CI whitelist, skip the repo unless
         # one of the CI's environment variable is set to true.