pkg/report: add Report.SkipPos

SkipPos is what pkg/instance needs,
but also will be needed for ParseAll.

4 files changed, 58 insertions, 26 deletions

diff --git a/pkg/instance/instance.go b/pkg/instance/instance.go
index d88838576..39de02017 100644
--- a/pkg/instance/instance.go
+++ b/pkg/instance/instance.go
@@ -6,7 +6,6 @@
 package instance
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
 	"net"
@@ -245,11 +244,7 @@ func (inst *inst) test() error {
 			rep := inst.reporter.Parse(testErr.Output)
 			if rep != nil && rep.Type == report.UnexpectedReboot {
 				// Avoid detecting any boot crash as "unexpected kernel reboot".
-				output := testErr.Output[rep.EndPos:]
-				if pos := bytes.IndexByte(testErr.Output[rep.StartPos:], '\n'); pos != -1 {
-					output = testErr.Output[rep.StartPos+pos:]
-				}
-				rep = inst.reporter.Parse(output)
+				rep = inst.reporter.Parse(testErr.Output[rep.SkipPos:])
 			}
 			if rep == nil {
 				rep = &report.Report{
diff --git a/pkg/report/fuzz.go b/pkg/report/fuzz.go
index 82b42849f..02f02c4db 100644
--- a/pkg/report/fuzz.go
+++ b/pkg/report/fuzz.go
@@ -11,7 +11,7 @@ import (
 
 func Fuzz(data []byte) int {
 	res := 0
-	for _, reporter := range fuzzReporters {
+	for os, reporter := range fuzzReporters {
 		typ := reporter.(*reporterWrapper).typ
 		containsCrash := reporter.ContainsCrash(data)
 		rep := reporter.Parse(data)
@@ -32,18 +32,41 @@ func Fuzz(data []byte) int {
 		if len(rep.Output) == 0 {
 			panic(fmt.Sprintf("%v: len(Output) == 0", typ))
 		}
+		switch os {
+		case "openbsd", "netbsd", "fuchsia":
+			// openbsd/netbsd has Start/End/SkipPos set incorrectly due to messing with /r/n.
+			// fuchsia because it symbolizes before parsing.
+			continue
+		}
 		if rep.StartPos != 0 && rep.EndPos != 0 && rep.StartPos >= rep.EndPos {
-			panic(fmt.Sprintf("%v: StartPos=%v >= EndPos=%v", typ, rep.StartPos, rep.EndPos))
+			panic(fmt.Sprintf("%v: bad StartPos\nStartPos=%v >= EndPos=%v",
+				typ, rep.StartPos, rep.EndPos))
 		}
 		if rep.EndPos > len(rep.Output) {
-			panic(fmt.Sprintf("%v: EndPos=%v > len(Output)=%v", typ, rep.EndPos, len(rep.Output)))
+			panic(fmt.Sprintf("%v: bad EndPos\nEndPos=%v > len(Output)=%v",
+				typ, rep.EndPos, len(rep.Output)))
+		}
+		if rep.SkipPos <= rep.StartPos || rep.SkipPos > rep.EndPos {
+			panic(fmt.Sprintf("%v: bad SkipPos\nSkipPos=%v: StartPos=%v EndPos=%v",
+				typ, rep.SkipPos, rep.StartPos, rep.EndPos))
+		}
+		// If we parse from StartPos, we must find the same report.
+		rep1 := reporter.Parse(data[rep.StartPos:])
+		if rep1 == nil || rep1.Title != rep.Title || rep1.StartPos != 0 {
+			title, startPos := "", -1
+			if rep1 != nil {
+				title, startPos = rep1.Title, rep1.StartPos
+			}
+			panic(fmt.Sprintf("%v: did not find the same reports at StartPos\n"+
+				"StartPos=%v/%v\nTitle0=%q\nTitle1=%q",
+				typ, rep.StartPos, startPos, rep.Title, title))
 		}
 	}
 	return res
 }
 
-var fuzzReporters = func() []Reporter {
-	var reporters []Reporter
+var fuzzReporters = func() map[string]Reporter {
+	reporters := make(map[string]Reporter)
 	for os := range ctors {
 		if os == "windows" {
 			continue
@@ -59,7 +82,7 @@ var fuzzReporters = func() []Reporter {
 		if _, ok := reporter.(*stub); ok {
 			continue
 		}
-		reporters = append(reporters, reporter)
+		reporters[os] = reporter
 	}
 	return reporters
 }()
diff --git a/pkg/report/report.go b/pkg/report/report.go
index 673407f92..e6d13b930 100644
--- a/pkg/report/report.go
+++ b/pkg/report/report.go
@@ -42,6 +42,8 @@ type Report struct {
 	// StartPos/EndPos denote region of output with oops message(s).
 	StartPos int
 	EndPos   int
+	// SkipPos is position in output where parsing for the next report should start.
+	SkipPos int
 	// Suppressed indicates whether the report should not be reported to user.
 	Suppressed bool
 	// Corrupted indicates whether the report is truncated of corrupted in some other way.
@@ -184,6 +186,15 @@ func (wrap *reporterWrapper) Parse(output []byte) *Report {
 	if pos := bytes.Index(rep.Report, []byte(VMDiagnosisStart)); pos != -1 {
 		rep.Report = rep.Report[:pos]
 	}
+	rep.SkipPos = len(output)
+	if pos := bytes.IndexByte(output[rep.StartPos:], '\n'); pos != -1 {
+		rep.SkipPos = rep.StartPos + pos
+	}
+	if rep.EndPos < rep.SkipPos {
+		// This generally should not happen.
+		// But openbsd does some hacks with /r/n which may lead to off-by-one EndPos.
+		rep.EndPos = rep.SkipPos
+	}
 	return rep
 }
 
diff --git a/pkg/report/report_test.go b/pkg/report/report_test.go
index aebcb45f8..39cd0deb6 100644
--- a/pkg/report/report_test.go
+++ b/pkg/report/report_test.go
@@ -186,22 +186,10 @@ func testParseImpl(t *testing.T, reporter Reporter, test *ParseTest) {
 	if rep == nil {
 		return
 	}
-	checkReport(t, rep, test)
-	if rep.StartPos != 0 {
-		// If we parse from StartPos, we must find the same report.
-		rep1 := reporter.Parse(test.Log[rep.StartPos:])
-		if rep1 == nil || rep1.Title != rep.Title {
-			t.Fatalf("did not find the same report from rep.StartPos=%v", rep.StartPos)
-		}
-		// If we parse from EndPos, we must not find the same report.
-		rep2 := reporter.Parse(test.Log[rep.EndPos:])
-		if rep2 != nil && rep2.Title == rep.Title {
-			t.Fatalf("found the same report after rep.EndPos=%v", rep.EndPos)
-		}
-	}
+	checkReport(t, reporter, rep, test)
 }
 
-func checkReport(t *testing.T, rep *Report, test *ParseTest) {
+func checkReport(t *testing.T, reporter Reporter, rep *Report, test *ParseTest) {
 	if test.HasReport && !bytes.Equal(rep.Report, test.Report) {
 		t.Fatalf("extracted wrong report:\n%s\nwant:\n%s", rep.Report, test.Report)
 	}
@@ -214,6 +202,9 @@ func checkReport(t *testing.T, rep *Report, test *ParseTest) {
 	if rep.EndPos > len(rep.Output) {
 		t.Fatalf("EndPos=%v > len(Output)=%v", rep.EndPos, len(rep.Output))
 	}
+	if rep.SkipPos <= rep.StartPos || rep.SkipPos > rep.EndPos {
+		t.Fatalf("bad SkipPos=%v: StartPos=%v EndPos=%v", rep.SkipPos, rep.StartPos, rep.EndPos)
+	}
 	if test.StartLine != "" {
 		if test.EndLine == "" {
 			test.EndLine = test.StartLine
@@ -226,6 +217,18 @@ func checkReport(t *testing.T, rep *Report, test *ParseTest) {
 				string(test.Log[rep.StartPos:rep.EndPos]))
 		}
 	}
+	if rep.StartPos != 0 {
+		// If we parse from StartPos, we must find the same report.
+		rep1 := reporter.Parse(test.Log[rep.StartPos:])
+		if rep1 == nil || rep1.Title != rep.Title || rep1.StartPos != 0 {
+			t.Fatalf("did not find the same report from rep.StartPos=%v", rep.StartPos)
+		}
+		// If we parse from EndPos, we must not find the same report.
+		rep2 := reporter.Parse(test.Log[rep.EndPos:])
+		if rep2 != nil && rep2.Title == rep.Title {
+			t.Fatalf("found the same report after rep.EndPos=%v", rep.EndPos)
+		}
+	}
 }
 
 func updateReportTest(t *testing.T, test *ParseTest, title string, corrupted, suppressed bool,