From aa6c0f2ad11fd4909fdeef375078b8bce3dc0aad Mon Sep 17 00:00:00 2001
From: Marc Herbert <marc.herbert@intel.com>
Date: Fri, 27 Mar 2020 21:19:20 -0700
Subject: [PATCH] topology: cmake: silence super chatty alsatplg unless
 VERBOSE=1

Successfully tested with both Make and Ninja on Linux.

Non-portable but approved by @jajanusz in former PR #2626

With this commit:

$                  make -C tools/build_tools/ | wc -l
    770

$ VERBOSE=anything make -C tools/build_tools/ | wc -l
  10387

Signed-off-by: Marc Herbert <marc.herbert@intel.com>
---
 tools/topology/CMakeLists.txt | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/tools/topology/CMakeLists.txt b/tools/topology/CMakeLists.txt
index d47577f18..82e3715a5 100644
--- a/tools/topology/CMakeLists.txt
+++ b/tools/topology/CMakeLists.txt
@@ -159,11 +159,25 @@ foreach(tplg ${TPLGS})
 		USES_TERMINAL
 	)
 
+# This use of VERBOSE relies on original CMake behavior.
+# From the add_custom_command() manual:
+#
+#    Use of VERBATIM is recommended as it enables correct behavior.
+#    When VERBATIM is not given the behavior is platform specific because
+#    there is no protection of tool-specific special characters.
+#
+# This is fine because:
+# - We don't expect alsatplg to work on Windows any time soon.
+# - CMake is too afraid to remove the original, no-VERBATIM behavior:
+#      https://gitlab.kitware.com/cmake/cmake/issues/18849
+#
+# Also note that in alsa-utils commit v1.2.2~15-gcbabe7a3f0cc, alsatplg
+# (accidentally?) started ignoring the verbosity level, now it's just
+# verbose or not.
 	add_custom_command(
 		OUTPUT ${output}.tplg
-		COMMAND alsatplg -v 1 -c ${output}.conf -o ${output}.tplg
+		COMMAND alsatplg \$\${VERBOSE:+-v 1} -c ${output}.conf -o ${output}.tplg
 		DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/${output}.conf
-		VERBATIM
 		USES_TERMINAL
 	)