1 files changed, 194 insertions, 0 deletions
diff --git a/extras/genpybind.py b/extras/genpybind.py
new file mode 100644
index 0000000..ac206ee
--- /dev/null
+++ b/extras/genpybind.py
@@ -0,0 +1,194 @@
+import os
+import pipes
+import subprocess
+import sys
+
+from waflib import Logs, Task, Context
+from waflib.Tools.c_preproc import scan as scan_impl
+# ^-- Note: waflib.extras.gccdeps.scan does not work for us,
+# due to its current implementation:
+# The -MD flag is injected into the {C,CXX}FLAGS environment variable and
+# dependencies are read out in a separate step after compiling by reading
+# the .d file saved alongside the object file.
+# As the genpybind task refers to a header file that is never compiled itself,
+# gccdeps will not be able to extract the list of dependencies.
+
+from waflib.TaskGen import feature, before_method
+
+
+def join_args(args):
+    return " ".join(pipes.quote(arg) for arg in args)
+
+
+def configure(cfg):
+    cfg.load("compiler_cxx")
+    cfg.load("python")
+    cfg.check_python_version(minver=(2, 7))
+    if not cfg.env.LLVM_CONFIG:
+        cfg.find_program("llvm-config", var="LLVM_CONFIG")
+    if not cfg.env.GENPYBIND:
+        cfg.find_program("genpybind", var="GENPYBIND")
+
+    # find clang reasource dir for builtin headers
+    cfg.env.GENPYBIND_RESOURCE_DIR = os.path.join(
+            cfg.cmd_and_log(cfg.env.LLVM_CONFIG + ["--libdir"]).strip(),
+            "clang",
+            cfg.cmd_and_log(cfg.env.LLVM_CONFIG + ["--version"]).strip())
+    if os.path.exists(cfg.env.GENPYBIND_RESOURCE_DIR):
+        cfg.msg("Checking clang resource dir", cfg.env.GENPYBIND_RESOURCE_DIR)
+    else:
+        cfg.fatal("Clang resource dir not found")
+
+
+@feature("genpybind")
+@before_method("process_source")
+def generate_genpybind_source(self):
+    """
+    Run genpybind on the headers provided in `source` and compile/link the
+    generated code instead.  This works by generating the code on the fly and
+    swapping the source node before `process_source` is run.
+    """
+    # name of module defaults to name of target
+    module = getattr(self, "module", self.target)
+
+    # create temporary source file in build directory to hold generated code
+    out = "genpybind-%s.%d.cpp" % (module, self.idx)
+    out = self.path.get_bld().find_or_declare(out)
+
+    task = self.create_task("genpybind", self.to_nodes(self.source), out)
+    # used to detect whether CFLAGS or CXXFLAGS should be passed to genpybind
+    task.features = self.features
+    task.module = module
+    # can be used to select definitions to include in the current module
+    # (when header files are shared by more than one module)
+    task.genpybind_tags = self.to_list(getattr(self, "genpybind_tags", []))
+    # additional include directories
+    task.includes = self.to_list(getattr(self, "includes", []))
+    task.genpybind = self.env.GENPYBIND
+
+    # Tell waf to compile/link the generated code instead of the headers
+    # originally passed-in via the `source` parameter. (see `process_source`)
+    self.source = [out]
+
+
+class genpybind(Task.Task): # pylint: disable=invalid-name
+    """
+    Runs genpybind on headers provided as input to this task.
+    Generated code will be written to the first (and only) output node.
+    """
+    quiet = True
+    color = "PINK"
+    scan = scan_impl
+
+    @staticmethod
+    def keyword():
+        return "Analyzing"
+
+    def run(self):
+        if not self.inputs:
+            return
+
+        args = self.find_genpybind() + self._arguments(
+                resource_dir=self.env.GENPYBIND_RESOURCE_DIR)
+
+        output = self.run_genpybind(args)
+
+        # For debugging / log output
+        pasteable_command = join_args(args)
+
+        # write generated code to file in build directory
+        # (will be compiled during process_source stage)
+        (output_node,) = self.outputs
+        output_node.write("// {}\n{}\n".format(
+            pasteable_command.replace("\n", "\n// "), output))
+
+    def find_genpybind(self):
+        return self.genpybind
+
+    def run_genpybind(self, args):
+        bld = self.generator.bld
+
+        kwargs = dict(cwd=bld.variant_dir)
+        if hasattr(bld, "log_command"):
+            bld.log_command(args, kwargs)
+        else:
+            Logs.debug("runner: {!r}".format(args))
+        proc = subprocess.Popen(
+            args, stdout=subprocess.PIPE, stderr=subprocess.PIPE, **kwargs)
+        stdout, stderr = proc.communicate()
+
+        if not isinstance(stdout, str):
+            stdout = stdout.decode(sys.stdout.encoding, errors="replace")
+        if not isinstance(stderr, str):
+            stderr = stderr.decode(sys.stderr.encoding, errors="replace")
+
+        if proc.returncode != 0:
+            bld.fatal(
+                "genpybind returned {code} during the following call:"
+                "\n{command}\n\n{stdout}\n\n{stderr}".format(
+                    code=proc.returncode,
+                    command=join_args(args),
+                    stdout=stdout,
+                    stderr=stderr,
+                ))
+
+        if stderr.strip():
+            Logs.debug("non-fatal warnings during genpybind run:\n{}".format(stderr))
+
+        return stdout
+
+    def _include_paths(self):
+        return self.generator.to_incnodes(self.includes + self.env.INCLUDES)
+
+    def _inputs_as_relative_includes(self):
+        include_paths = self._include_paths()
+        relative_includes = []
+        for node in self.inputs:
+            for inc in include_paths:
+                if node.is_child_of(inc):
+                    relative_includes.append(node.path_from(inc))
+                    break
+            else:
+                self.generator.bld.fatal("could not resolve {}".format(node))
+        return relative_includes
+
+    def _arguments(self, genpybind_parse=None, resource_dir=None):
+        args = []
+        relative_includes = self._inputs_as_relative_includes()
+        is_cxx = "cxx" in self.features
+
+        # options for genpybind
+        args.extend(["--genpybind-module", self.module])
+        if self.genpybind_tags:
+            args.extend(["--genpybind-tag"] + self.genpybind_tags)
+        if relative_includes:
+            args.extend(["--genpybind-include"] + relative_includes)
+        if genpybind_parse:
+            args.extend(["--genpybind-parse", genpybind_parse])
+
+        args.append("--")
+
+        # headers to be processed by genpybind
+        args.extend(node.abspath() for node in self.inputs)
+
+        args.append("--")
+
+        # options for clang/genpybind-parse
+        args.append("-D__GENPYBIND__")
+        args.append("-xc++" if is_cxx else "-xc")
+        has_std_argument = False
+        for flag in self.env["CXXFLAGS" if is_cxx else "CFLAGS"]:
+            flag = flag.replace("-std=gnu", "-std=c")
+            if flag.startswith("-std=c"):
+                has_std_argument = True
+            args.append(flag)
+        if not has_std_argument:
+            args.append("-std=c++14")
+        args.extend("-I{}".format(n.abspath()) for n in self._include_paths())
+        args.extend("-D{}".format(p) for p in self.env.DEFINES)
+
+        # point to clang resource dir, if specified
+        if resource_dir:
+            args.append("-resource-dir={}".format(resource_dir))
+
+        return args