gallium/aux: Split u_tracepoints.[ch] generation

Allow for separate rules to be used to generate the .c and .h (partially
to make it easier for scons build, and partially because that is just a
better practice).

Signed-off-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7974>

src/gallium/auxiliary/meson.build

@@ -485,19 +485,32 @@ endif
 
 u_trace_py = files('util/u_trace.py')
 
-files_u_tracepoints = custom_target(
-  'u_tracepoints.[ch]',
+files_libgallium += custom_target(
+  'u_tracepoints.c',
   input: 'util/u_tracepoints.py',
-  output: ['u_tracepoints.c', 'u_tracepoints.h'],
+  output: 'u_tracepoints.c',
   command: [
     prog_python, '@INPUT@',
     '-p', join_paths(meson.source_root(), 'src/gallium/auxiliary/util/'),
-    '-C', '@OUTPUT0@',
-    '-H', '@OUTPUT1@',
+    '-C', '@OUTPUT@',
   ],
   depend_files: u_trace_py,
 )
+
+files_u_tracepoints = custom_target(
+  'u_tracepoints.h',
+  input: 'util/u_tracepoints.py',
+  output: 'u_tracepoints.h',
+  command: [
+    prog_python, '@INPUT@',
+    '-p', join_paths(meson.source_root(), 'src/gallium/auxiliary/util/'),
+    '-H', '@OUTPUT@',
+  ],
+  depend_files: u_trace_py,
+)
+
 files_libgallium += files_u_tracepoints
+
 idep_u_tracepoints = declare_dependency(
   sources: files_u_tracepoints,
 )

src/gallium/auxiliary/util/u_trace.py

@@ -205,15 +205,18 @@ void __trace_${trace_name}(struct u_trace *ut
 """
 
 def utrace_generate(cpath, hpath):
-    hdr = os.path.basename(hpath)
-    with open(cpath, 'wb') as f:
-        f.write(Template(src_template, output_encoding='utf-8').render(
-            hdr=hdr,
-            HEADERS=HEADERS,
-            TRACEPOINTS=TRACEPOINTS))
+    if cpath is not None:
+        hdr = os.path.basename(cpath).rsplit('.', 1)[0] + '.h'
+        with open(cpath, 'wb') as f:
+            f.write(Template(src_template, output_encoding='utf-8').render(
+                hdr=hdr,
+                HEADERS=HEADERS,
+                TRACEPOINTS=TRACEPOINTS))
 
-    with open(hpath, 'wb') as f:
-        f.write(Template(hdr_template, output_encoding='utf-8').render(
-            hdrname=hdr.rstrip('.h').upper(),
-            HEADERS=HEADERS,
-            TRACEPOINTS=TRACEPOINTS))
+    if hpath is not None:
+        hdr = os.path.basename(hpath)
+        with open(hpath, 'wb') as f:
+            f.write(Template(hdr_template, output_encoding='utf-8').render(
+                hdrname=hdr.rstrip('.h').upper(),
+                HEADERS=HEADERS,
+                TRACEPOINTS=TRACEPOINTS))

src/gallium/auxiliary/util/u_tracepoints.py

@@ -29,8 +29,8 @@ import sys
 #
 parser = argparse.ArgumentParser()
 parser.add_argument('-p', '--import-path', required=True)
-parser.add_argument('-C', '--src', required=True)
-parser.add_argument('-H', '--hdr', required=True)
+parser.add_argument('-C', '--src')
+parser.add_argument('-H', '--hdr')
 args = parser.parse_args()
 sys.path.insert(0, args.import_path)