1 files changed, 160 insertions, 0 deletions
diff --git a/vendor/github.com/openshift/imagebuilder/evaluator.go b/vendor/github.com/openshift/imagebuilder/evaluator.go
new file mode 100644
index 000000000..83263127e
--- /dev/null
+++ b/vendor/github.com/openshift/imagebuilder/evaluator.go
@@ -0,0 +1,160 @@
+package imagebuilder
+
+import (
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/docker/docker/builder/dockerfile/command"
+	"github.com/docker/docker/builder/dockerfile/parser"
+)
+
+// ParseDockerfile parses the provided stream as a canonical Dockerfile
+func ParseDockerfile(r io.Reader) (*parser.Node, error) {
+	result, err := parser.Parse(r)
+	if err != nil {
+		return nil, err
+	}
+	return result.AST, nil
+}
+
+// Environment variable interpolation will happen on these statements only.
+var replaceEnvAllowed = map[string]bool{
+	command.Env:       true,
+	command.Label:     true,
+	command.Add:       true,
+	command.Copy:      true,
+	command.Workdir:   true,
+	command.Expose:    true,
+	command.Volume:    true,
+	command.User:      true,
+	commandStopSignal: true,
+	commandArg:        true,
+}
+
+// Certain commands are allowed to have their args split into more
+// words after env var replacements. Meaning:
+//   ENV foo="123 456"
+//   EXPOSE $foo
+// should result in the same thing as:
+//   EXPOSE 123 456
+// and not treat "123 456" as a single word.
+// Note that: EXPOSE "$foo" and EXPOSE $foo are not the same thing.
+// Quotes will cause it to still be treated as single word.
+var allowWordExpansion = map[string]bool{
+	command.Expose: true,
+}
+
+// Step represents the input Env and the output command after all
+// post processing of the command arguments is done.
+type Step struct {
+	Env []string
+
+	Command  string
+	Args     []string
+	Flags    []string
+	Attrs    map[string]bool
+	Message  string
+	Original string
+}
+
+// Resolve transforms a parsed Dockerfile line into a command to execute,
+// resolving any arguments.
+//
+// Almost all nodes will have this structure:
+// Child[Node, Node, Node] where Child is from parser.Node.Children and each
+// node comes from parser.Node.Next. This forms a "line" with a statement and
+// arguments and we process them in this normalized form by hitting
+// evaluateTable with the leaf nodes of the command and the Builder object.
+//
+// ONBUILD is a special case; in this case the parser will emit:
+// Child[Node, Child[Node, Node...]] where the first node is the literal
+// "onbuild" and the child entrypoint is the command of the ONBUILD statement,
+// such as `RUN` in ONBUILD RUN foo. There is special case logic in here to
+// deal with that, at least until it becomes more of a general concern with new
+// features.
+func (b *Step) Resolve(ast *parser.Node) error {
+	cmd := ast.Value
+	upperCasedCmd := strings.ToUpper(cmd)
+
+	// To ensure the user is given a decent error message if the platform
+	// on which the daemon is running does not support a builder command.
+	if err := platformSupports(strings.ToLower(cmd)); err != nil {
+		return err
+	}
+
+	attrs := ast.Attributes
+	original := ast.Original
+	flags := ast.Flags
+	strList := []string{}
+	msg := upperCasedCmd
+
+	if len(ast.Flags) > 0 {
+		msg += " " + strings.Join(ast.Flags, " ")
+	}
+
+	if cmd == "onbuild" {
+		if ast.Next == nil {
+			return fmt.Errorf("ONBUILD requires at least one argument")
+		}
+		ast = ast.Next.Children[0]
+		strList = append(strList, ast.Value)
+		msg += " " + ast.Value
+
+		if len(ast.Flags) > 0 {
+			msg += " " + strings.Join(ast.Flags, " ")
+		}
+
+	}
+
+	// count the number of nodes that we are going to traverse first
+	// so we can pre-create the argument and message array. This speeds up the
+	// allocation of those list a lot when they have a lot of arguments
+	cursor := ast
+	var n int
+	for cursor.Next != nil {
+		cursor = cursor.Next
+		n++
+	}
+	msgList := make([]string, n)
+
+	var i int
+	envs := b.Env
+	for ast.Next != nil {
+		ast = ast.Next
+		var str string
+		str = ast.Value
+		if replaceEnvAllowed[cmd] {
+			var err error
+			var words []string
+
+			if allowWordExpansion[cmd] {
+				words, err = ProcessWords(str, envs)
+				if err != nil {
+					return err
+				}
+				strList = append(strList, words...)
+			} else {
+				str, err = ProcessWord(str, envs)
+				if err != nil {
+					return err
+				}
+				strList = append(strList, str)
+			}
+		} else {
+			strList = append(strList, str)
+		}
+		msgList[i] = ast.Value
+		i++
+	}
+
+	msg += " " + strings.Join(msgList, " ")
+
+	b.Message = msg
+	b.Command = cmd
+	b.Args = strList
+	b.Original = original
+	b.Attrs = attrs
+	b.Flags = flags
+	return nil
+}