pkg/csource: replace go:generate with go:embed

go:embed is a more modern way to do this and it does
not require a special Makefile step.
Since go:embed cannot use paths that contains "..",
the actual embeding is moved to executor package.

1 files changed, 73 insertions, 0 deletions

diff --git a/executor/embed.go b/executor/embed.go
new file mode 100644
index 000000000..a02413a12
--- /dev/null
+++ b/executor/embed.go
@@ -0,0 +1,73 @@
+// Copyright 2024 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package executor
+
+import (
+	"bytes"
+	"embed"
+	"fmt"
+	"io/fs"
+	"path"
+	"regexp"
+)
+
+//go:embed common*.h kvm*.h android/*.h
+var src embed.FS
+
+// CommonHeader contains all executor common headers used by pkg/csource to generate C reproducers.
+// All includes in common.h are transitively replaced with their contents so that it's just a single blob.
+var CommonHeader = func() []byte {
+	data, err := src.ReadFile("common.h")
+	if err != nil {
+		panic(err)
+	}
+	headers := make(map[string]bool)
+	for _, glob := range []string{"*.h", "android/*.h"} {
+		files, err := fs.Glob(src, glob)
+		if err != nil {
+			panic(err)
+		}
+		for _, file := range files {
+			if file == "common.h" || file == "common_ext_example.h" {
+				continue
+			}
+			headers[file] = true
+		}
+	}
+	// To not hardcode concrete order in which headers need to be replaced
+	// we just iteratively try to replace whatever headers can be replaced
+	// on the current step.
+	for len(headers) != 0 {
+		relacedSomething := false
+		for file := range headers {
+			replace := []byte("#include \"" + path.Base(file) + "\"")
+			if !bytes.Contains(data, replace) {
+				replace = []byte("#include \"android/" + path.Base(file) + "\"")
+				if !bytes.Contains(data, replace) {
+					continue
+				}
+			}
+			contents, err := src.ReadFile(file)
+			if err != nil {
+				panic(err)
+			}
+			data = bytes.ReplaceAll(data, replace, contents)
+			delete(headers, file)
+			relacedSomething = true
+		}
+		if !relacedSomething {
+			panic(fmt.Sprintf("can't find includes for %v", headers))
+		}
+	}
+	// Remove `//` comments, but keep lines which start with `//%`.
+	for _, remove := range []string{
+		"(\n|^)\\s*//$",
+		"(\n|^)\\s*//[^%].*",
+		"\\s*//$",
+		"\\s*//[^%].*",
+	} {
+		data = regexp.MustCompile(remove).ReplaceAll(data, nil)
+	}
+	return data
+}()