Import globbing from Soong

Add globbing with dependency checking to blueprint.  Calling
ModuleContext.GlobWithDeps or SingletonContext.GlobWithDeps will return
a list of files that match the globs, while also adding efficient
dependencies to rerun the primary builder if a file that matches the
glob is added or removed.

Also use the globbing support for optional_subdirs=, subdirs= and build=
lines in blueprints files.  The globbing slightly changes the behavior
of subname= lines, it no longer falls back to looking for a file called
"Blueprints".  Blueprint files that need to include a subdirectory with
a different name can use build= instead of subdir= to directly include
them.  The Blueprints file is updated to reset subname="Blueprints" in
case we want to include subdirectories inside blueprint and the primary
builder has changed the subname.

Also adds a new test directory that contains a simple primary builder
tree to test regeneration for globbing, and runs the tests in travis.

Change-Id: I83ce525fd11e11579cc58ba5308d01ca8eea7bc6

1 files changed, 77 insertions, 0 deletions

diff --git a/bootstrap/bpglob/bpglob.go b/bootstrap/bpglob/bpglob.go
new file mode 100644
index 0000000..cb6633b
--- /dev/null
+++ b/bootstrap/bpglob/bpglob.go
@@ -0,0 +1,77 @@
+// Copyright 2015 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// bpglob is the command line tool that checks if the list of files matching a glob has
+// changed, and only updates the output file list if it has changed.  It is used to optimize
+// out build.ninja regenerations when non-matching files are added.  See
+// github.com/google/blueprint/bootstrap/glob.go for a longer description.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+
+	"github.com/google/blueprint/pathtools"
+)
+
+var (
+	out = flag.String("o", "", "file to write list of files that match glob")
+
+	excludes multiArg
+)
+
+func init() {
+	flag.Var(&excludes, "e", "pattern to exclude from results")
+}
+
+type multiArg []string
+
+func (m *multiArg) String() string {
+	return `""`
+}
+
+func (m *multiArg) Set(s string) error {
+	*m = append(*m, s)
+	return nil
+}
+
+func (m *multiArg) Get() interface{} {
+	return m
+}
+
+func usage() {
+	fmt.Fprintf(os.Stderr, "usage: bpglob -o out glob\n")
+	flag.PrintDefaults()
+	os.Exit(2)
+}
+
+func main() {
+	flag.Parse()
+
+	if *out == "" {
+		fmt.Fprintf(os.Stderr, "error: -o is required\n")
+		usage()
+	}
+
+	if flag.NArg() != 1 {
+		usage()
+	}
+
+	_, err := pathtools.GlobWithDepFile(flag.Arg(0), *out, *out+".d", excludes)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error: %s\n", err.Error())
+		os.Exit(1)
+	}
+}