1 files changed, 137 insertions, 0 deletions
diff --git a/vendor/github.com/moby/sys/mount/flags.go b/vendor/github.com/moby/sys/mount/flags.go
new file mode 100644
index 000000000..d514a9d8e
--- /dev/null
+++ b/vendor/github.com/moby/sys/mount/flags.go
@@ -0,0 +1,137 @@
+package mount
+
+import (
+	"fmt"
+	"strings"
+)
+
+var flags = map[string]struct {
+	clear bool
+	flag  int
+}{
+	"defaults":      {false, 0},
+	"ro":            {false, RDONLY},
+	"rw":            {true, RDONLY},
+	"suid":          {true, NOSUID},
+	"nosuid":        {false, NOSUID},
+	"dev":           {true, NODEV},
+	"nodev":         {false, NODEV},
+	"exec":          {true, NOEXEC},
+	"noexec":        {false, NOEXEC},
+	"sync":          {false, SYNCHRONOUS},
+	"async":         {true, SYNCHRONOUS},
+	"dirsync":       {false, DIRSYNC},
+	"remount":       {false, REMOUNT},
+	"mand":          {false, MANDLOCK},
+	"nomand":        {true, MANDLOCK},
+	"atime":         {true, NOATIME},
+	"noatime":       {false, NOATIME},
+	"diratime":      {true, NODIRATIME},
+	"nodiratime":    {false, NODIRATIME},
+	"bind":          {false, BIND},
+	"rbind":         {false, RBIND},
+	"unbindable":    {false, UNBINDABLE},
+	"runbindable":   {false, RUNBINDABLE},
+	"private":       {false, PRIVATE},
+	"rprivate":      {false, RPRIVATE},
+	"shared":        {false, SHARED},
+	"rshared":       {false, RSHARED},
+	"slave":         {false, SLAVE},
+	"rslave":        {false, RSLAVE},
+	"relatime":      {false, RELATIME},
+	"norelatime":    {true, RELATIME},
+	"strictatime":   {false, STRICTATIME},
+	"nostrictatime": {true, STRICTATIME},
+}
+
+var validFlags = map[string]bool{
+	"":          true,
+	"size":      true,
+	"mode":      true,
+	"uid":       true,
+	"gid":       true,
+	"nr_inodes": true,
+	"nr_blocks": true,
+	"mpol":      true,
+}
+
+var propagationFlags = map[string]bool{
+	"bind":        true,
+	"rbind":       true,
+	"unbindable":  true,
+	"runbindable": true,
+	"private":     true,
+	"rprivate":    true,
+	"shared":      true,
+	"rshared":     true,
+	"slave":       true,
+	"rslave":      true,
+}
+
+// MergeTmpfsOptions merge mount options to make sure there is no duplicate.
+func MergeTmpfsOptions(options []string) ([]string, error) {
+	// We use collisions maps to remove duplicates.
+	// For flag, the key is the flag value (the key for propagation flag is -1)
+	// For data=value, the key is the data
+	flagCollisions := map[int]bool{}
+	dataCollisions := map[string]bool{}
+
+	var newOptions []string
+	// We process in reverse order
+	for i := len(options) - 1; i >= 0; i-- {
+		option := options[i]
+		if option == "defaults" {
+			continue
+		}
+		if f, ok := flags[option]; ok && f.flag != 0 {
+			// There is only one propagation mode
+			key := f.flag
+			if propagationFlags[option] {
+				key = -1
+			}
+			// Check to see if there is collision for flag
+			if !flagCollisions[key] {
+				// We prepend the option and add to collision map
+				newOptions = append([]string{option}, newOptions...)
+				flagCollisions[key] = true
+			}
+			continue
+		}
+		opt := strings.SplitN(option, "=", 2)
+		if len(opt) != 2 || !validFlags[opt[0]] {
+			return nil, fmt.Errorf("Invalid tmpfs option %q", opt)
+		}
+		if !dataCollisions[opt[0]] {
+			// We prepend the option and add to collision map
+			newOptions = append([]string{option}, newOptions...)
+			dataCollisions[opt[0]] = true
+		}
+	}
+
+	return newOptions, nil
+}
+
+// Parse fstab type mount options into mount() flags
+// and device specific data
+func parseOptions(options string) (int, string) {
+	var (
+		flag int
+		data []string
+	)
+
+	for _, o := range strings.Split(options, ",") {
+		// If the option does not exist in the flags table or the flag
+		// is not supported on the platform,
+		// then it is a data value for a specific fs type
+		if f, exists := flags[o]; exists && f.flag != 0 {
+			if f.clear {
+				flag &= ^f.flag
+			} else {
+				flag |= f.flag
+			}
+		} else {
+			data = append(data, o)
+		}
+	}
+	return flag, strings.Join(data, ",")
+}