From fd97e8019e2ab166d9475ed59782c86247d8430b Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Tue, 18 May 2021 11:03:05 +0200
Subject: [PATCH] Move embedded remote helpers to cmd/safcm/

To permit using safcm as an actual library the helpers must be passed to
rpc.DialSSH() and not directly embedded.
---
 .gitignore                      |  2 +-
 Makefile                        |  2 +-
 cmd/safcm-remote/build.sh       |  2 +-
 {remote => cmd/safcm}/remote.go | 10 +++++-----
 cmd/safcm/sync.go               | 16 ++++++++++++----
 rpc/conn.go                     |  3 +++
 rpc/dial.go                     | 15 +++++++++++----
 7 files changed, 34 insertions(+), 16 deletions(-)
 rename {remote => cmd/safcm}/remote.go (82%)

diff --git a/.gitignore b/.gitignore
index 139f3d5..8e87b2f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+/cmd/safcm/remote/
 /cmd/safcm/testdata/ssh/project/no-changes.example.org/
 /cmd/safcm/testdata/ssh/ssh/authorized_keys
 /cmd/safcm/testdata/ssh/ssh/id_ed25519
@@ -5,6 +6,5 @@
 /cmd/safcm/testdata/ssh/ssh/known_hosts
 /cmd/safcm/testdata/ssh/sshd/ssh_host_key
 /cmd/safcm/testdata/ssh/sshd/ssh_host_key.pub
-/remote/helpers/
 /safcm
 /tags
diff --git a/Makefile b/Makefile
index fa2db0b..4bf77c2 100644
--- a/Makefile
+++ b/Makefile
@@ -27,7 +27,7 @@ lint:
 	shellcheck cmd/safcm/testdata/ssh/prepare.sh
 
 clean:
-	rm -rf remote/helpers/
+	rm -rf cmd/safcm/remote/
 	rm -f safcm
 	rm -f cmd/safcm/testdata/ssh/ssh/authorized_keys
 	rm -f cmd/safcm/testdata/ssh/ssh/id_ed25519
diff --git a/cmd/safcm-remote/build.sh b/cmd/safcm-remote/build.sh
index 3ee7ccd..73957ed 100755
--- a/cmd/safcm-remote/build.sh
+++ b/cmd/safcm-remote/build.sh
@@ -30,7 +30,7 @@ build_arm() {
 }
 
 
-dest=../../remote/helpers
+dest=../safcm/remote
 
 mkdir -p "$dest"
 
diff --git a/remote/remote.go b/cmd/safcm/remote.go
similarity index 82%
rename from remote/remote.go
rename to cmd/safcm/remote.go
index 3a41987..4fbb7d4 100644
--- a/remote/remote.go
+++ b/cmd/safcm/remote.go
@@ -15,13 +15,13 @@
 // You should have received a copy of the GNU General Public License
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-package remote
+package main
 
 import (
 	"embed"
 )
 
-// Helpers contains remote helper binaries for different operating systems and
-// architectures.
-//go:embed helpers/*
-var Helpers embed.FS
+// RemoteHelpers contains remote helper binaries for different operating
+// systems and architectures.
+//go:embed remote/*
+var RemoteHelpers embed.FS
diff --git a/cmd/safcm/sync.go b/cmd/safcm/sync.go
index 1a482b3..bee0133 100644
--- a/cmd/safcm/sync.go
+++ b/cmd/safcm/sync.go
@@ -20,6 +20,7 @@ package main
 import (
 	"flag"
 	"fmt"
+	"io/fs"
 	"log"
 	"os"
 	"os/signal"
@@ -369,15 +370,22 @@ func (s *Sync) Host(wg *sync.WaitGroup) error {
 		wg.Done()
 	}()
 
+	helpers, err := fs.Sub(RemoteHelpers, "remote")
+	if err != nil {
+		conn.Kill()
+		return err
+	}
+
 	// Connect to remote host
 	user := s.host.SshUser
 	if user == "" {
 		user = s.config.SshUser
 	}
-	err := conn.DialSSH(rpc.SSHConfig{
-		Host:      s.host.Name,
-		User:      user,
-		SshConfig: s.config.SshConfig,
+	err = conn.DialSSH(rpc.SSHConfig{
+		Host:          s.host.Name,
+		User:          user,
+		SshConfig:     s.config.SshConfig,
+		RemoteHelpers: helpers,
 	})
 	if err != nil {
 		conn.Kill()
diff --git a/rpc/conn.go b/rpc/conn.go
index 03b7485..3f7ade1 100644
--- a/rpc/conn.go
+++ b/rpc/conn.go
@@ -20,6 +20,7 @@ package rpc
 import (
 	"bufio"
 	"fmt"
+	"io/fs"
 	"os/exec"
 	"strings"
 	"sync"
@@ -36,6 +37,8 @@ type Conn struct {
 	sshRemote string
 	sshOpts   []string
 
+	remoteHelpers fs.FS
+
 	cmd  *exec.Cmd
 	conn *safcm.GobConn
 }
diff --git a/rpc/dial.go b/rpc/dial.go
index c0c6cd4..c098714 100644
--- a/rpc/dial.go
+++ b/rpc/dial.go
@@ -24,18 +24,20 @@ import (
 	"encoding/hex"
 	"fmt"
 	"io"
+	"io/fs"
 	"os/exec"
 	"strconv"
 	"strings"
 
 	"ruderich.org/simon/safcm"
-	"ruderich.org/simon/safcm/remote"
 )
 
 type SSHConfig struct {
 	Host      string
 	User      string // optional
 	SshConfig string // optional
+
+	RemoteHelpers fs.FS
 }
 
 func (c *Conn) DialSSH(cfg SSHConfig) error {
@@ -43,6 +45,11 @@ func (c *Conn) DialSSH(cfg SSHConfig) error {
 		return fmt.Errorf("cannot reuse Conn")
 	}
 
+	if cfg.RemoteHelpers == nil {
+		return fmt.Errorf("SSHConfig.RemoteHelpers not set")
+	}
+	c.remoteHelpers = cfg.RemoteHelpers
+
 	remote := cfg.Host
 	if cfg.User != "" {
 		remote = cfg.User + "@" + cfg.Host
@@ -208,9 +215,9 @@ f
 		return err
 	}
 
-	// Get embedded helper binary
-	helper, err := remote.Helpers.ReadFile(
-		fmt.Sprintf("helpers/%s-%s", goos, goarch))
+	// Get remote helper binary
+	helper, err := fs.ReadFile(c.remoteHelpers,
+		fmt.Sprintf("%s-%s", goos, goarch))
 	if err != nil {
 		return fmt.Errorf("remote not built for GOOS/GOARCH %s/%s",
 			goos, goarch)
-- 
2.45.2