Allow additional arguments to be passed into hooks

If a packager wants to be able to support addititional arguments on his
hook this will allow them to setup the configuration with these arguments.

For example this would allow a hook developer to add support for a --debug
flag to change the level of debugging in his hook.

In order to complete this task, I had to vendor in the latest
github.com://opencontainers/runtime-tools, which caused me to have to fix a
Mount and Capability interface calls

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

vendor/github.com/opencontainers/runtime-tools/filepath/abs.go

@@ -0,0 +1,48 @@
+package filepath
+
+import (
+	"regexp"
+	"strings"
+)
+
+var windowsAbs = regexp.MustCompile(`^[a-zA-Z]:\\.*$`)
+
+// Abs is a version of path/filepath's Abs with an explicit operating
+// system and current working directory.
+func Abs(os, path, cwd string) (_ string, err error) {
+	if IsAbs(os, path) {
+		return Clean(os, path), nil
+	}
+	return Clean(os, Join(os, cwd, path)), nil
+}
+
+// IsAbs is a version of path/filepath's IsAbs with an explicit
+// operating system.
+func IsAbs(os, path string) bool {
+	if os == "windows" {
+		// FIXME: copy hideous logic from Go's
+		// src/path/filepath/path_windows.go into somewhere where we can
+		// put 3-clause BSD licensed code.
+		return windowsAbs.MatchString(path)
+	}
+	sep := Separator(os)
+
+	// POSIX has [1]:
+	//
+	// > If a pathname begins with two successive <slash> characters,
+	// > the first component following the leading <slash> characters
+	// > may be interpreted in an implementation-defined manner,
+	// > although more than two leading <slash> characters shall be
+	// > treated as a single <slash> character.
+	//
+	// And Boost treats // as non-absolute [2], but Linux [3,4], Python
+	// [5] and Go [6] all treat // as absolute.
+	//
+	// [1]: http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13
+	// [2]: https://github.com/boostorg/filesystem/blob/boost-1.64.0/test/path_test.cpp#L861
+	// [3]: http://man7.org/linux/man-pages/man7/path_resolution.7.html
+	// [4]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/filesystems/path-lookup.md?h=v4.12#n41
+	// [5]: https://github.com/python/cpython/blob/v3.6.1/Lib/posixpath.py#L64-L66
+	// [6]: https://go.googlesource.com/go/+/go1.8.3/src/path/path.go#199
+	return strings.HasPrefix(path, string(sep))
+}

vendor/github.com/opencontainers/runtime-tools/filepath/ancestor.go

@@ -0,0 +1,32 @@
+package filepath
+
+import (
+	"fmt"
+	"strings"
+)
+
+// IsAncestor returns true when pathB is an strict ancestor of pathA,
+// and false where the paths are equal or pathB is outside of pathA.
+// Paths that are not absolute will be made absolute with Abs.
+func IsAncestor(os, pathA, pathB, cwd string) (_ bool, err error) {
+	if pathA == pathB {
+		return false, nil
+	}
+
+	pathA, err = Abs(os, pathA, cwd)
+	if err != nil {
+		return false, err
+	}
+	pathB, err = Abs(os, pathB, cwd)
+	if err != nil {
+		return false, err
+	}
+	sep := Separator(os)
+	if !strings.HasSuffix(pathA, string(sep)) {
+		pathA = fmt.Sprintf("%s%c", pathA, sep)
+	}
+	if pathA == pathB {
+		return false, nil
+	}
+	return strings.HasPrefix(pathB, pathA), nil
+}

vendor/github.com/opencontainers/runtime-tools/filepath/clean.go

@@ -0,0 +1,74 @@
+package filepath
+
+import (
+	"fmt"
+	"strings"
+)
+
+// Clean is an explicit-OS version of path/filepath's Clean.
+func Clean(os, path string) string {
+	abs := IsAbs(os, path)
+	sep := Separator(os)
+	elements := strings.Split(path, string(sep))
+
+	// Replace multiple Separator elements with a single one.
+	for i := 0; i < len(elements); i++ {
+		if len(elements[i]) == 0 {
+			elements = append(elements[:i], elements[i+1:]...)
+			i--
+		}
+	}
+
+	// Eliminate each . path name element (the current directory).
+	for i := 0; i < len(elements); i++ {
+		if elements[i] == "." && len(elements) > 1 {
+			elements = append(elements[:i], elements[i+1:]...)
+			i--
+		}
+	}
+
+	// Eliminate each inner .. path name element (the parent directory)
+	// along with the non-.. element that precedes it.
+	for i := 1; i < len(elements); i++ {
+		if i == 1 && abs && sep == '\\' {
+			continue
+		}
+		if i > 0 && elements[i] == ".." {
+			elements = append(elements[:i-1], elements[i+1:]...)
+			i -= 2
+		}
+	}
+
+	// Eliminate .. elements that begin a rooted path:
+	// that is, replace "/.." by "/" at the beginning of a path,
+	// assuming Separator is '/'.
+	offset := 0
+	if sep == '\\' {
+		offset = 1
+	}
+	if abs {
+		for len(elements) > offset && elements[offset] == ".." {
+			elements = append(elements[:offset], elements[offset+1:]...)
+		}
+	}
+
+	cleaned := strings.Join(elements, string(sep))
+	if abs {
+		if sep == '/' {
+			cleaned = fmt.Sprintf("%c%s", sep, cleaned)
+		} else if len(elements) == 1 {
+			cleaned = fmt.Sprintf("%s%c", cleaned, sep)
+		}
+	}
+
+	// If the result of this process is an empty string, Clean returns
+	// the string ".".
+	if len(cleaned) == 0 {
+		cleaned = "."
+	}
+
+	if cleaned == path {
+		return path
+	}
+	return Clean(os, cleaned)
+}

vendor/github.com/opencontainers/runtime-tools/filepath/doc.go

@@ -0,0 +1,6 @@
+// Package filepath implements Go's filepath package with explicit
+// operating systems (and for some functions and explicit working
+// directory).  This allows tools built for one OS to operate on paths
+// targeting another OS.  For example, a Linux build can determine
+// whether a path is absolute on Linux or on Windows.
+package filepath

vendor/github.com/opencontainers/runtime-tools/filepath/join.go

@@ -0,0 +1,9 @@
+package filepath
+
+import "strings"
+
+// Join is an explicit-OS version of path/filepath's Join.
+func Join(os string, elem ...string) string {
+	sep := Separator(os)
+	return Clean(os, strings.Join(elem, string(sep)))
+}

vendor/github.com/opencontainers/runtime-tools/filepath/separator.go

@@ -0,0 +1,9 @@
+package filepath
+
+// Separator is an explicit-OS version of path/filepath's Separator.
+func Separator(os string) rune {
+	if os == "windows" {
+		return '\\'
+	}
+	return '/'
+}