Merge v1.2.1-master

Signed-off-by: Emile Vauge <emile@vauge.com>

vendor/github.com/prometheus/procfs/mdstat.go

@@ -3,7 +3,6 @@ package procfs
 import (
 	"fmt"
 	"io/ioutil"
-	"path"
 	"regexp"
 	"strconv"
 	"strings"
@@ -32,36 +31,22 @@ type MDStat struct {
 
 // ParseMDStat parses an mdstat-file and returns a struct with the relevant infos.
 func (fs FS) ParseMDStat() (mdstates []MDStat, err error) {
-	mdStatusFilePath := path.Join(string(fs), "mdstat")
+	mdStatusFilePath := fs.Path("mdstat")
 	content, err := ioutil.ReadFile(mdStatusFilePath)
 	if err != nil {
 		return []MDStat{}, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
 	}
 
-	mdStatusFile := string(content)
-
-	lines := strings.Split(mdStatusFile, "\n")
-	var currentMD string
-
-	// Each md has at least the deviceline, statusline and one empty line afterwards
-	// so we will have probably something of the order len(lines)/3 devices
-	// so we use that for preallocation.
-	estimateMDs := len(lines) / 3
-	mdStates := make([]MDStat, 0, estimateMDs)
-
+	mdStates := []MDStat{}
+	lines := strings.Split(string(content), "\n")
 	for i, l := range lines {
 		if l == "" {
-			// Skip entirely empty lines.
 			continue
 		}
-
 		if l[0] == ' ' {
-			// Those lines are not the beginning of a md-section.
 			continue
 		}
-
 		if strings.HasPrefix(l, "Personalities") || strings.HasPrefix(l, "unused") {
-			// We aren't interested in lines with general info.
 			continue
 		}
 
@@ -69,32 +54,30 @@ func (fs FS) ParseMDStat() (mdstates []MDStat, err error) {
 		if len(mainLine) < 3 {
 			return mdStates, fmt.Errorf("error parsing mdline: %s", l)
 		}
-		currentMD = mainLine[0]      // name of md-device
-		activityState := mainLine[2] // activity status of said md-device
+		mdName := mainLine[0]
+		activityState := mainLine[2]
 
 		if len(lines) <= i+3 {
-			return mdStates, fmt.Errorf("error parsing %s: entry for %s has fewer lines than expected", mdStatusFilePath, currentMD)
+			return mdStates, fmt.Errorf(
+				"error parsing %s: too few lines for md device %s",
+				mdStatusFilePath,
+				mdName,
+			)
 		}
 
-		active, total, size, err := evalStatusline(lines[i+1]) // parse statusline, always present
+		active, total, size, err := evalStatusline(lines[i+1])
 		if err != nil {
 			return mdStates, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
 		}
 
-		//
-		// Now get the number of synced blocks.
-		//
-
-		// Get the line number of the syncing-line.
-		var j int
-		if strings.Contains(lines[i+2], "bitmap") { // then skip the bitmap line
+		// j is the line number of the syncing-line.
+		j := i + 2
+		if strings.Contains(lines[i+2], "bitmap") { // skip bitmap line
 			j = i + 3
-		} else {
-			j = i + 2
 		}
 
-		// If device is syncing at the moment, get the number of currently synced bytes,
-		// otherwise that number equals the size of the device.
+		// If device is syncing at the moment, get the number of currently
+		// synced bytes, otherwise that number equals the size of the device.
 		syncedBlocks := size
 		if strings.Contains(lines[j], "recovery") || strings.Contains(lines[j], "resync") {
 			syncedBlocks, err = evalBuildline(lines[j])
@@ -103,8 +86,14 @@ func (fs FS) ParseMDStat() (mdstates []MDStat, err error) {
 			}
 		}
 
-		mdStates = append(mdStates, MDStat{currentMD, activityState, active, total, size, syncedBlocks})
-
+		mdStates = append(mdStates, MDStat{
+			Name:          mdName,
+			ActivityState: activityState,
+			DisksActive:   active,
+			DisksTotal:    total,
+			BlocksTotal:   size,
+			BlocksSynced:  syncedBlocks,
+		})
 	}
 
 	return mdStates, nil
@@ -112,47 +101,38 @@ func (fs FS) ParseMDStat() (mdstates []MDStat, err error) {
 
 func evalStatusline(statusline string) (active, total, size int64, err error) {
 	matches := statuslineRE.FindStringSubmatch(statusline)
-
-	// +1 to make it more obvious that the whole string containing the info is also returned as matches[0].
-	if len(matches) != 3+1 {
-		return 0, 0, 0, fmt.Errorf("unexpected number matches found in statusline: %s", statusline)
+	if len(matches) != 4 {
+		return 0, 0, 0, fmt.Errorf("unexpected statusline: %s", statusline)
 	}
 
 	size, err = strconv.ParseInt(matches[1], 10, 64)
 	if err != nil {
-		return 0, 0, 0, fmt.Errorf("%s in statusline: %s", err, statusline)
+		return 0, 0, 0, fmt.Errorf("unexpected statusline %s: %s", statusline, err)
 	}
 
 	total, err = strconv.ParseInt(matches[2], 10, 64)
 	if err != nil {
-		return 0, 0, 0, fmt.Errorf("%s in statusline: %s", err, statusline)
+		return 0, 0, 0, fmt.Errorf("unexpected statusline %s: %s", statusline, err)
 	}
 
 	active, err = strconv.ParseInt(matches[3], 10, 64)
 	if err != nil {
-		return 0, 0, 0, fmt.Errorf("%s in statusline: %s", err, statusline)
+		return 0, 0, 0, fmt.Errorf("unexpected statusline %s: %s", statusline, err)
 	}
 
 	return active, total, size, nil
 }
 
-// Gets the size that has already been synced out of the sync-line.
-func evalBuildline(buildline string) (int64, error) {
+func evalBuildline(buildline string) (syncedBlocks int64, err error) {
 	matches := buildlineRE.FindStringSubmatch(buildline)
-
-	// +1 to make it more obvious that the whole string containing the info is also returned as matches[0].
-	if len(matches) < 1+1 {
-		return 0, fmt.Errorf("too few matches found in buildline: %s", buildline)
+	if len(matches) != 2 {
+		return 0, fmt.Errorf("unexpected buildline: %s", buildline)
 	}
 
-	if len(matches) > 1+1 {
-		return 0, fmt.Errorf("too many matches found in buildline: %s", buildline)
-	}
-
-	syncedSize, err := strconv.ParseInt(matches[1], 10, 64)
+	syncedBlocks, err = strconv.ParseInt(matches[1], 10, 64)
 	if err != nil {
 		return 0, fmt.Errorf("%s in buildline: %s", err, buildline)
 	}
 
-	return syncedSize, nil
+	return syncedBlocks, nil
 }