fix podman logs --tail when log is bigger than pagesize

Signed-off-by: Paul Holzinger <[email protected]>
vrothberg · Aug 11, 2020 · d9c86fd · d9c86fd
1 parent dcf39f0
commit d9c86fd
Show file tree

Hide file tree

Showing 3 changed files with 12 additions and 12 deletions.
diff --git a/libpod/logs/log.go b/libpod/logs/log.go
@@ -101,11 +101,14 @@ func getTailLog(path string, tail int) ([]*LogLine, error) {
 			if err != nil {
 				if errors.Cause(err) == io.EOF {
 					inputs <- []string{leftover}
-					close(inputs)
-					break
+				} else {
+					logrus.Error(err)
 				}
-				logrus.Error(err)
 				close(inputs)
+				if err := f.Close(); err != nil {
+					logrus.Error(err)
+				}
+				break
 			}
 			line := strings.Split(s+leftover, "\n")
 			if len(line) > 1 {
@@ -136,9 +139,6 @@ func getTailLog(path string, tail int) ([]*LogLine, error) {
 		}
 		// if we have enough loglines, we can hangup
 		if nllCounter >= tail {
-			if err := f.Close(); err != nil {
-				logrus.Error(err)
-			}
 			break
 		}
 	}

diff --git a/libpod/logs/reversereader/reversereader.go b/libpod/logs/reversereader/reversereader.go
@@ -60,7 +60,7 @@ func (r *ReverseReader) Read() (string, error) {
 	if int64(n) < r.readSize {
 		b = b[0:n]
 	}
-	// Set to the next page boundary
-	r.offset = -r.readSize
+	// Move the offset one pagesize up
+	r.offset -= r.readSize
 	return string(b), nil
 }
diff --git a/test/e2e/logs_test.go b/test/e2e/logs_test.go
@@ -72,16 +72,16 @@ var _ = Describe("Podman logs", func() {
 		Expect(len(results.OutputToStringArray())).To(Equal(0))
 	})
 
-	It("tail 99 lines", func() {
-		logc := podmanTest.Podman([]string{"run", "-dt", ALPINE, "sh", "-c", "echo podman; echo podman; echo podman"})
+	It("tail 800 lines", func() {
+		logc := podmanTest.Podman([]string{"run", "-dt", ALPINE, "sh", "-c", "i=1; while [ \"$i\" -ne 1000 ]; do echo \"line $i\"; i=$((i + 1)); done"})
 		logc.WaitWithDefaultTimeout()
 		Expect(logc).To(Exit(0))
 		cid := logc.OutputToString()
 
-		results := podmanTest.Podman([]string{"logs", "--tail", "99", cid})
+		results := podmanTest.Podman([]string{"logs", "--tail", "800", cid})
 		results.WaitWithDefaultTimeout()
 		Expect(results).To(Exit(0))
-		Expect(len(results.OutputToStringArray())).To(Equal(3))
+		Expect(len(results.OutputToStringArray())).To(Equal(800))
 	})
 
 	It("tail 2 lines with timestamps", func() {