Script to download prebuilt dependencies into a local folder

.gitignore

@@ -6,6 +6,7 @@
 *_generated.go
 *_generated.h
 /.dmypy.json
+/dependencies
 /tags
 /build/
 /linux-package/

Makefile

@@ -69,3 +69,7 @@ prepare-for-cross-compile: clean all
 cross-compile:
 	python3 setup.py linux-package --skip-code-generation
 	
+FORCE: ;
+
+dependencies: FORCE
+	go run bypy/get-deps.go

bypy/get-deps.go

@@ -0,0 +1,152 @@
+// License: GPLv3 Copyright: 2023, Kovid Goyal, <kovid at kovidgoyal.net>
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/fs"
+	"net/http"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"runtime"
+	"strings"
+)
+
+const folder = "dependencies"
+
+var _ = fmt.Print
+
+func exit(x any) {
+	switch v := x.(type) {
+	case error:
+		if v == nil {
+			os.Exit(0)
+		}
+	case string:
+		if v == "" {
+			os.Exit(0)
+		}
+	case int:
+		os.Exit(v)
+	}
+	fmt.Fprintf(os.Stderr, "\x1b[31mError\x1b[m: %s", x)
+	os.Exit(1)
+}
+
+func cached_download(url string) string {
+	fname := filepath.Base(url)
+	fmt.Println("Downloading", fname)
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		exit(err)
+	}
+	if etag, err := os.ReadFile(filepath.Join(folder, "etag")); err == nil {
+		if _, err := os.Stat(filepath.Join(folder, fname)); err == nil {
+			req.Header.Add("If-None-Match", string(etag))
+		}
+	}
+
+	client := &http.Client{}
+	resp, err := client.Do(req)
+	if err != nil {
+		exit(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		if resp.StatusCode == http.StatusNotModified {
+			return filepath.Join(folder, fname)
+		}
+		exit(fmt.Errorf("The server responded with the HTTP error: %s", resp.Status))
+	}
+	f, err := os.Create(filepath.Join(folder, fname))
+	if err != nil {
+		exit(err)
+	}
+	defer f.Close()
+	if _, err := io.Copy(f, resp.Body); err != nil {
+		exit(fmt.Errorf("Failed to download file with error: %w", err))
+	}
+	if etag := resp.Header.Get("ETag"); etag != "" {
+		if err := os.WriteFile(filepath.Join(folder, "etag"), []byte(etag), 0o644); err != nil {
+			exit(err)
+		}
+	}
+	return f.Name()
+}
+
+func relocate_pkgconfig(path, old_prefix, new_prefix string) error {
+	raw, err := os.ReadFile(path)
+	if err != nil {
+		return err
+	}
+	nraw := bytes.ReplaceAll(raw, []byte(old_prefix), []byte(new_prefix))
+	return os.WriteFile(path, nraw, 0o644)
+}
+
+func main() {
+	_, filename, _, _ := runtime.Caller(0)
+	base_dir := filepath.Dir(filepath.Dir(filename))
+	if err := os.Chdir(base_dir); err != nil {
+		exit(err)
+	}
+	data, err := os.ReadFile(".github/workflows/ci.py")
+	if err != nil {
+		exit(err)
+	}
+	pat := regexp.MustCompile("BUNDLE_URL = '(.+?)'")
+	prefix := "/sw/sw"
+	var url string
+	if m := pat.FindStringSubmatch(string(data)); len(m) < 2 {
+		exit("Failed to find BUNDLE_URL in ci.py")
+	} else {
+		url = m[1]
+	}
+	var which string
+	switch runtime.GOOS {
+	case "darwin":
+		prefix = "/Users/Shared/kitty-build/sw/sw"
+		which = "macos"
+	case "linux":
+		which = "linux"
+		if runtime.GOARCH != "amd64" {
+			exit("Pre-built dependencies are only available for the amd64 CPU architecture")
+		}
+	}
+	if which == "" {
+		exit("Prebuilt dependencies are only available for Linux and macOS")
+	}
+	url = strings.Replace(url, "{}", which, 1)
+	if err := os.RemoveAll(filepath.Join(folder, "root")); err != nil {
+		exit(err)
+	}
+	if err := os.MkdirAll(folder, 0o755); err != nil {
+		exit(err)
+	}
+	tarfile, _ := filepath.Abs(cached_download(url))
+	root, _ := filepath.Abs(filepath.Join(folder, "root"))
+	if err := os.MkdirAll(root, 0o755); err != nil {
+		exit(err)
+	}
+	cmd := exec.Command("tar", "xf", tarfile)
+	cmd.Dir = root
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err = cmd.Run(); err != nil {
+		exit(err)
+	}
+	if err = filepath.WalkDir(root, func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if d.Type().IsRegular() && strings.HasSuffix(d.Name(), ".pc") {
+			err = relocate_pkgconfig(path, prefix, root)
+		}
+		return err
+	}); err != nil {
+		exit(err)
+	}
+}