Extend testing of procspy.

test/fs/fs.go

@@ -0,0 +1,199 @@
+package fs
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"strings"
+	"syscall"
+	"time"
+)
+
+type mockInode struct{}
+
+type dir struct {
+	mockInode
+	name    string
+	entries map[string]FS
+	stat    syscall.Stat_t
+}
+
+// File is a mock file
+type File struct {
+	mockInode
+	FName     string
+	FContents string
+	FStat     syscall.Stat_t
+}
+
+// FS is a mock filesystem
+type FS interface {
+	os.FileInfo
+	ReadDir(string) ([]os.FileInfo, error)
+	ReadFile(string) ([]byte, error)
+	Lstat(string, *syscall.Stat_t) error
+	Stat(string, *syscall.Stat_t) error
+	Open(string) (io.ReadWriteCloser, error)
+}
+
+// Dir creates a new directory with the given entries.
+func Dir(name string, entries ...FS) FS {
+	result := dir{
+		name:    name,
+		entries: map[string]FS{},
+	}
+
+	for _, entry := range entries {
+		result.entries[entry.Name()] = entry
+	}
+
+	return result
+}
+
+func split(path string) (string, string) {
+	if !strings.HasPrefix(path, "/") {
+		panic(path)
+	}
+
+	comps := strings.SplitN(path, "/", 3)
+	if len(comps) == 2 {
+		return comps[1], "/"
+	}
+
+	return comps[1], "/" + comps[2]
+}
+
+func (mockInode) Size() int64        { return 0 }
+func (mockInode) Mode() os.FileMode  { return 0 }
+func (mockInode) ModTime() time.Time { return time.Now() }
+func (mockInode) Sys() interface{}   { return nil }
+
+func (p dir) Name() string { return p.name }
+func (p dir) IsDir() bool  { return true }
+
+func (p dir) ReadDir(path string) ([]os.FileInfo, error) {
+	if path == "/" {
+		result := []os.FileInfo{}
+		for _, v := range p.entries {
+			result = append(result, v)
+		}
+		return result, nil
+	}
+
+	head, tail := split(path)
+	fs, ok := p.entries[head]
+	if !ok {
+		return nil, fmt.Errorf("Not found: %s", path)
+	}
+
+	return fs.ReadDir(tail)
+}
+
+func (p dir) ReadFile(path string) ([]byte, error) {
+	if path == "/" {
+		return nil, fmt.Errorf("I'm a directory!")
+	}
+
+	head, tail := split(path)
+	fs, ok := p.entries[head]
+	if !ok {
+		return nil, fmt.Errorf("Not found: %s", path)
+	}
+
+	return fs.ReadFile(tail)
+}
+
+func (p dir) Lstat(path string, stat *syscall.Stat_t) error {
+	if path == "/" {
+		return nil
+	}
+
+	head, tail := split(path)
+	fs, ok := p.entries[head]
+	if !ok {
+		return fmt.Errorf("Not found: %s", path)
+	}
+
+	return fs.Lstat(tail, stat)
+}
+
+func (p dir) Stat(path string, stat *syscall.Stat_t) error {
+	if path == "/" {
+		return nil
+	}
+
+	head, tail := split(path)
+	fs, ok := p.entries[head]
+	if !ok {
+		return fmt.Errorf("Not found: %s", path)
+	}
+
+	return fs.Stat(tail, stat)
+}
+
+func (p dir) Open(path string) (io.ReadWriteCloser, error) {
+	if path == "/" {
+		return nil, fmt.Errorf("I'm a directory!")
+	}
+
+	head, tail := split(path)
+	fs, ok := p.entries[head]
+	if !ok {
+		return nil, fmt.Errorf("Not found: %s", path)
+	}
+
+	return fs.Open(tail)
+}
+
+// Name implements os.FileInfo
+func (p File) Name() string { return p.FName }
+
+// IsDir implements os.FileInfo
+func (p File) IsDir() bool { return false }
+
+// ReadDir implements FS
+func (p File) ReadDir(path string) ([]os.FileInfo, error) {
+	return nil, fmt.Errorf("I'm a file!")
+}
+
+// ReadFile implements FS
+func (p File) ReadFile(path string) ([]byte, error) {
+	if path != "/" {
+		return nil, fmt.Errorf("I'm a file!")
+	}
+	return []byte(p.FContents), nil
+}
+
+// Lstat implements FS
+func (p File) Lstat(path string, stat *syscall.Stat_t) error {
+	if path != "/" {
+		return fmt.Errorf("I'm a file!")
+	}
+	*stat = p.FStat
+	return nil
+}
+
+// Stat implements FS
+func (p File) Stat(path string, stat *syscall.Stat_t) error {
+	if path != "/" {
+		return fmt.Errorf("I'm a file!")
+	}
+	*stat = p.FStat
+	return nil
+}
+
+// Open implements FS
+func (p File) Open(path string) (io.ReadWriteCloser, error) {
+	if path != "/" {
+		return nil, fmt.Errorf("I'm a file!")
+	}
+	return struct {
+		io.ReadWriter
+		io.Closer
+	}{
+		bytes.NewBuffer([]byte(p.FContents)),
+		ioutil.NopCloser(nil),
+	}, nil
+}