feat(go): add Phase 1 parity sidecar

go-agent/internal/system/state.go

@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+// Package system captures one cached, injectable view of live host state.
+package system
+
+import (
+	"os"
+	"path/filepath"
+	"sort"
+	"strconv"
+	"strings"
+
+	"codeberg.org/anassaeneroi/enodia-sentinal/go-agent/internal/model"
+)
+
+// Capture reads process state once from procRoot. Transient per-process read
+// failures degrade to empty fields, matching Python's fail-open Process view.
+func Capture(procRoot string) (model.State, error) {
+	if procRoot == "" {
+		procRoot = "/proc"
+	}
+	entries, err := os.ReadDir(procRoot)
+	if err != nil {
+		return model.State{}, err
+	}
+	processes := make([]model.Process, 0, len(entries))
+	for _, entry := range entries {
+		pid, err := strconv.Atoi(entry.Name())
+		if err != nil || !entry.IsDir() {
+			continue
+		}
+		base := filepath.Join(procRoot, entry.Name())
+		processes = append(processes, model.Process{
+			PID:     pid,
+			Comm:    strings.TrimSpace(readText(filepath.Join(base, "comm"))),
+			Cmdline: strings.TrimSpace(strings.ReplaceAll(readText(filepath.Join(base, "cmdline")), "\x00", " ")),
+			Exe:     readLink(filepath.Join(base, "exe")),
+		})
+	}
+	sort.Slice(processes, func(i, j int) bool { return processes[i].PID < processes[j].PID })
+	return model.State{Processes: processes}, nil
+}
+
+func readText(path string) string {
+	raw, err := os.ReadFile(path)
+	if err != nil {
+		return ""
+	}
+	return string(raw)
+}
+
+func readLink(path string) string {
+	target, err := os.Readlink(path)
+	if err != nil {
+		return ""
+	}
+	return target
+}

go-agent/internal/system/state_test.go

@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package system
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestCaptureUsesInjectableProcRoot(t *testing.T) {
+	root := t.TempDir()
+	proc := filepath.Join(root, "42")
+	if err := os.Mkdir(proc, 0o700); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(proc, "comm"), []byte("bash\n"), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(filepath.Join(proc, "cmdline"), []byte("bash\x00-i\x00"), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Symlink("/tmp/x (deleted)", filepath.Join(proc, "exe")); err != nil {
+		t.Fatal(err)
+	}
+	state, err := Capture(root)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(state.Processes) != 1 {
+		t.Fatalf("unexpected processes: %#v", state.Processes)
+	}
+	got := state.Processes[0]
+	if got.PID != 42 || got.Comm != "bash" || got.Cmdline != "bash -i" || got.Exe != "/tmp/x (deleted)" {
+		t.Fatalf("unexpected process: %#v", got)
+	}
+}