util: Add script to check gmmproc version

This adds a new utility script for Meson builds to check on what gmmproc
version was used (or is to be used) to generate the sources, so that we
can know whether we are ready to use compiler directives to export
symbols by defining macros during the build of the various -mm C++
modules.

9 files changed, 101 insertions, 2 deletions

diff --git a/Makefile.am b/Makefile.am
index cbb7451..68019a7 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -30,6 +30,7 @@ dist_build_support_DATA =		\
 	am_include/dist-changelog.am		\
 	am_include/doc-reference.am		\
 	am_include/generate-binding.am \
+  util/build_scripts/check-dllexport-usage.py \
   util/build_scripts/dist-build-scripts.py \
   util/build_scripts/dist-changelog.py \
   util/build_scripts/doc-reference.py \
diff --git a/README b/README
index d4bea2a..0cf0f24 100644
--- a/README
+++ b/README
@@ -221,6 +221,11 @@ util/build_scripts/dist-build-scripts.py:
   not checked into the git repository. All .gitignore files and an empty build/
   directory are removed
 
+util/build_scripts/check-dllexport-usage.py:
+  Command that checks on the gmmproc version that is to be used or been used
+  to generate the sources, to check whether to use compiler directives to
+  export symbols.  Only used for Visual Studio or clang-cl builds.
+
 Documentation utilities (Meson and Autotools)
 ---------------------------------------------
 
diff --git a/meson.build b/meson.build
index fbc7e5e..92c639a 100644
--- a/meson.build
+++ b/meson.build
@@ -73,6 +73,7 @@ endforeach
 # These are installed so that mm-common-get can copy them
 # into projects at Meson setup or configure time.
 meson_build_support_basefiles = [
+  'check-dllexport-usage.py',
   'dist-build-scripts.py',
   'dist-changelog.py',
   'doc-reference.py',
diff --git a/skeletonmm/meson.build b/skeletonmm/meson.build
index 2274d32..0c885c6 100644
--- a/skeletonmm/meson.build
+++ b/skeletonmm/meson.build
@@ -102,6 +102,7 @@ generate_binding = script_dir / 'generate-binding.py'
 doc_reference = script_dir / 'doc-reference.py'
 dist_changelog = script_dir / 'dist-changelog.py'
 dist_build_scripts = script_dir / 'dist-build-scripts.py'
+check_dllexport_usage = script_dir / 'check-dllexport-usage.py'
 dist_cmd = project_source_root / 'tools' / 'dist-cmd.py' # Must be committed to git.
 
 if maintainer_mode and mm_common_get.found()
diff --git a/skeletonmm/untracked/README b/skeletonmm/untracked/README
index 8082503..b51c2cb 100644
--- a/skeletonmm/untracked/README
+++ b/skeletonmm/untracked/README
@@ -19,7 +19,8 @@ untracked/doc/doc-install.pl
               doc-postprocess.pl
               doxygen-extra.css
               tagfile-to-devhelp2.xsl
-untracked/build_scripts/dist-build-scripts.py
+untracked/build_scripts/check-dllexport-usage.py
+                        dist-build-scripts.py
                         dist-changelog.py
                         doc-reference.py
                         generate-binding.py
diff --git a/util/build_scripts/check-dllexport-usage.py b/util/build_scripts/check-dllexport-usage.py
new file mode 100644
index 0000000..09875ad
--- /dev/null
+++ b/util/build_scripts/check-dllexport-usage.py
@@ -0,0 +1,87 @@
+#!/usr/bin/env python3
+#
+# Check for the first line in a file generated with gmmproc,
+# to see which gmmproc version was used, to see whether
+# to enable __declspec(dllexport to export symbols).  This
+# is *not* intended for source files that are not generated
+# with gmmproc.
+#
+# Author: Chun-wei Fan April 2, 2020
+
+import argparse
+import os
+import sys
+
+min_required_gmmproc_ver = '2.64.3'
+
+parser = argparse.ArgumentParser(description='Check gmmproc version used.')
+parser.add_argument('--file',
+                    dest='file',
+                    help='Generated .cc/.h file to check gmmproc version')
+parser.add_argument('--gmmprocdir',
+                    dest='gmmprocdir',
+                    help='Directory where gmmproc is located')
+args = parser.parse_args()
+
+if args.file is None and args.gmmprocdir is None:
+    raise ValueError('Either --file or --gmmprocdir must be specified')
+
+if args.gmmprocdir is not None:
+    # gmmprocdir is specified: Check version string in gmmproc
+    gmmproc_path = os.path.join(args.gmmprocdir, 'gmmproc')
+    if not os.path.exists(gmmproc_path):
+        raise ValueError('A valid directory to locate gmmproc must be ' \
+                         'specified with --gmmprocdir=<directory>')
+
+    gmmproc_ver_str = None
+    with open(gmmproc_path, 'r') as f:
+        for line in f:
+            if line.startswith('  $main::glibmm_version = '):
+                gmmproc_ver_str = line[line.find('\"') + 1:line.rfind('\"')]
+
+    if gmmproc_ver_str is None:
+        raise ValueError('The gmmproc at %s is invalid' % gmmproc_path)
+
+    gmmproc_ver = gmmproc_ver_str.split('.')
+else:
+    # A pre-generated file is specified via --file
+    if not os.path.exists(args.file):
+        raise FileNotFoundError('File specified with --file does not exist')
+
+    # We only allow .h/.cc files to run this check
+    if not args.file.endswith('.cc') and \
+       not args.file.endswith('.h'):
+        raise ValueError('Only .cc/.h files are accepted here')
+
+    # Now grab the first line of the file we are checking for
+    f = open(args.file)
+    firstline = f.readline()
+    f.close()
+
+    # Check for gmmproc signature...
+    if not firstline.startswith('// Generated by gmmproc '):
+       raise ValueError('Specified file is not generated by gmmproc')
+
+    tokens = firstline.split()
+    gmmproc_ver = tokens[tokens.index('gmmproc') + 1].split('.')
+
+# Now compare the gmmproc version against the one we want
+# (2.64.3 or later)
+gmmproc_major = int(gmmproc_ver[0])
+gmmproc_minor = int(gmmproc_ver[1])
+gmmproc_micro = int(gmmproc_ver[2])
+
+min_required_ver = min_required_gmmproc_ver.split('.')
+min_major_ver = int(min_required_ver[0])
+min_minor_ver = int(min_required_ver[1])
+min_micro_ver = int(min_required_ver[2])
+
+if gmmproc_major > min_major_ver or \
+   (gmmproc_major == min_major_ver and \
+    gmmproc_minor > min_minor_ver) or \
+   (gmmproc_major == min_major_ver and \
+    gmmproc_minor == min_minor_ver and \
+    gmmproc_micro >= min_micro_ver):
+    sys.exit(0)
+else:
+    sys.exit(1)
diff --git a/util/build_scripts/dist-build-scripts.py b/util/build_scripts/dist-build-scripts.py
index 7318bc7..bdcda10 100755
--- a/util/build_scripts/dist-build-scripts.py
+++ b/util/build_scripts/dist-build-scripts.py
@@ -19,6 +19,7 @@ os.makedirs(dist_script_dir, exist_ok=True)
 
 # Distribute files that mm-common-get has copied to src_script_dir.
 files = [
+  'check-dllexport-usage.py',
   'dist-build-scripts.py',
   'dist-changelog.py',
   'doc-reference.py',
diff --git a/util/mm-common-get.1.in b/util/mm-common-get.1.in
index ff8996c..951f7ea 100644
--- a/util/mm-common-get.1.in
+++ b/util/mm-common-get.1.in
@@ -30,6 +30,8 @@ are listed below.
 .BI "Meson build scripts copied to " BUILDSCRIPT-DIR :
 .PD 0
 .IP
+.I check-dllexport-usage.py
+.IP
 .I dist-build-scripts.py
 .IP
 .I dist-changelog.py
diff --git a/util/mm-common-get.in b/util/mm-common-get.in
index e0b28f0..8a21f02 100644
--- a/util/mm-common-get.in
+++ b/util/mm-common-get.in
@@ -41,7 +41,7 @@ doctooldir = args.doctool_dir
 print(progname + ': putting Meson build scripts in ' + buildscriptdir)
 # Create the destination directory, if it does not exist.
 os.makedirs(buildscriptdir, exist_ok=True)
-for file in ['dist-build-scripts.py', 'dist-changelog.py', 'doc-reference.py', 'generate-binding.py']:
+for file in ['check-dllexport-usage.py', 'dist-build-scripts.py', 'dist-changelog.py', 'doc-reference.py', 'generate-binding.py']:
   src_file = os.path.join(pkgdatadir, 'build', file)
   dest_file = os.path.join(buildscriptdir, file)
   # Don't update the timestamp of dest_file, if it's equal to src_file.