1 files changed, 76 insertions, 0 deletions
diff --git a/integration-cli/docker_cli_logs_test.go b/integration-cli/docker_cli_logs_test.go
new file mode 100644
index 0000000000..8fcf4d7333
--- /dev/null
+++ b/integration-cli/docker_cli_logs_test.go
@@ -0,0 +1,76 @@
+package main
+
+import (
+	"fmt"
+	"os/exec"
+	"testing"
+)
+
+// This used to work, it test a log of PageSize-1 (gh#4851)
+func TestLogsContainerSmallerThanPage(t *testing.T) {
+	testLen := 32767
+	runCmd := exec.Command(dockerBinary, "run", "-d", "busybox", "sh", "-c", fmt.Sprintf("for i in $(seq 1 %d); do echo -n =; done; echo", testLen))
+	out, _, _, err := runCommandWithStdoutStderr(runCmd)
+	errorOut(err, t, fmt.Sprintf("run failed with errors: %v", err))
+
+	cleanedContainerID := stripTrailingCharacters(out)
+	exec.Command(dockerBinary, "wait", cleanedContainerID).Run()
+
+	logsCmd := exec.Command(dockerBinary, "logs", cleanedContainerID)
+	out, _, _, err = runCommandWithStdoutStderr(logsCmd)
+	errorOut(err, t, fmt.Sprintf("failed to log container: %v %v", out, err))
+
+	if len(out) != testLen+1 {
+		t.Fatalf("Expected log length of %d, received %d\n", testLen+1, len(out))
+	}
+
+	deleteContainer(cleanedContainerID)
+
+	logDone("logs - logs container running echo smaller than page size")
+}
+
+// Regression test: When going over the PageSize, it used to panic (gh#4851)
+func TestLogsContainerBiggerThanPage(t *testing.T) {
+	testLen := 32768
+	runCmd := exec.Command(dockerBinary, "run", "-d", "busybox", "sh", "-c", fmt.Sprintf("for i in $(seq 1 %d); do echo -n =; done; echo", testLen))
+	out, _, _, err := runCommandWithStdoutStderr(runCmd)
+	errorOut(err, t, fmt.Sprintf("run failed with errors: %v", err))
+
+	cleanedContainerID := stripTrailingCharacters(out)
+	exec.Command(dockerBinary, "wait", cleanedContainerID).Run()
+
+	logsCmd := exec.Command(dockerBinary, "logs", cleanedContainerID)
+	out, _, _, err = runCommandWithStdoutStderr(logsCmd)
+	errorOut(err, t, fmt.Sprintf("failed to log container: %v %v", out, err))
+
+	if len(out) != testLen+1 {
+		t.Fatalf("Expected log length of %d, received %d\n", testLen+1, len(out))
+	}
+
+	deleteContainer(cleanedContainerID)
+
+	logDone("logs - logs container running echo bigger than page size")
+}
+
+// Regression test: When going much over the PageSize, it used to block (gh#4851)
+func TestLogsContainerMuchBiggerThanPage(t *testing.T) {
+	testLen := 33000
+	runCmd := exec.Command(dockerBinary, "run", "-d", "busybox", "sh", "-c", fmt.Sprintf("for i in $(seq 1 %d); do echo -n =; done; echo", testLen))
+	out, _, _, err := runCommandWithStdoutStderr(runCmd)
+	errorOut(err, t, fmt.Sprintf("run failed with errors: %v", err))
+
+	cleanedContainerID := stripTrailingCharacters(out)
+	exec.Command(dockerBinary, "wait", cleanedContainerID).Run()
+
+	logsCmd := exec.Command(dockerBinary, "logs", cleanedContainerID)
+	out, _, _, err = runCommandWithStdoutStderr(logsCmd)
+	errorOut(err, t, fmt.Sprintf("failed to log container: %v %v", out, err))
+
+	if len(out) != testLen+1 {
+		t.Fatalf("Expected log length of %d, received %d\n", testLen+1, len(out))
+	}
+
+	deleteContainer(cleanedContainerID)
+
+	logDone("logs - logs container running echo much bigger than page size")
+}