From dfe9a7943bf7a926e51b319a2c2f73e4b4b4cf43 Mon Sep 17 00:00:00 2001
From: Jonas Devlieghere <jonas@devlieghere.com>
Date: Wed, 4 Dec 2019 16:06:48 -0800
Subject: [PATCH] [lldb/Reproducers] Override capture with
 LLDB_CAPTURE_REPRODUCER env var

Make it possible to override reproducer capture with the
LLDB_CAPTURE_REPRODUCER environment variable.

The goal of this change is twofold.

(1) I want to be able to enable capturing reproducers during regular
    test runs, both locally and on the bots. To do so I need a way to
    force capture. I cannot do this through the Python API, because
    reproducer capture must be enabled *before* the debugger
    initialized, which happens automatically when doing `import lldb`.

(2) I want to provide an escape hatch for when reproducers are enabled
    by default. Downstream we have reproducer capture enabled by default
    in the driver.

This patch solves both problems by overriding the reproducer mode based
on the environment variable. Acceptable values are 0/1 and ON/OFF.
---
 lldb/source/Utility/Reproducer.cpp            | 10 ++++++++++
 .../Reproducer/TestCaptureEnvOverride.test    | 20 +++++++++++++++++++
 lldb/test/Shell/Reproducer/lit.local.cfg      |  1 +
 3 files changed, 31 insertions(+)
 create mode 100644 lldb/test/Shell/Reproducer/TestCaptureEnvOverride.test

diff --git a/lldb/source/Utility/Reproducer.cpp b/lldb/source/Utility/Reproducer.cpp
index e0806f5f5981..8a28e9b13675 100644
--- a/lldb/source/Utility/Reproducer.cpp
+++ b/lldb/source/Utility/Reproducer.cpp
@@ -25,6 +25,16 @@ llvm::Error Reproducer::Initialize(ReproducerMode mode,
   lldbassert(!InstanceImpl() && "Already initialized.");
   InstanceImpl().emplace();
 
+  // The environment can override the capture mode.
+  if (mode != ReproducerMode::Replay) {
+    std::string env =
+        llvm::StringRef(getenv("LLDB_CAPTURE_REPRODUCER")).lower();
+    if (env == "0" || env == "off")
+      mode = ReproducerMode::Off;
+    else if (env == "1" || env == "on")
+      mode = ReproducerMode::Capture;
+  }
+
   switch (mode) {
   case ReproducerMode::Capture: {
     if (!root) {
diff --git a/lldb/test/Shell/Reproducer/TestCaptureEnvOverride.test b/lldb/test/Shell/Reproducer/TestCaptureEnvOverride.test
new file mode 100644
index 000000000000..a8e7bdec250e
--- /dev/null
+++ b/lldb/test/Shell/Reproducer/TestCaptureEnvOverride.test
@@ -0,0 +1,20 @@
+# UNSUPPORTED: system-windows
+# This tests the LLDB_CAPTURE_REPRODUCER override.
+
+# RUN: %lldb -b -o 'reproducer status' --capture --capture-path %t.repro /bin/ls | FileCheck %s --check-prefix CAPTURE
+# RUN: %lldb -b -o 'reproducer status' --capture | FileCheck %s --check-prefix CAPTURE
+
+# RUN: LLDB_CAPTURE_REPRODUCER=1 %lldb -b -o 'reproducer status' | FileCheck %s --check-prefix CAPTURE
+# RUN: LLDB_CAPTURE_REPRODUCER=ON %lldb -b -o 'reproducer status' | FileCheck %s --check-prefix CAPTURE
+# RUN: LLDB_CAPTURE_REPRODUCER=on %lldb -b -o 'reproducer status' | FileCheck %s --check-prefix CAPTURE
+
+# RUN: LLDB_CAPTURE_REPRODUCER=0 %lldb -b -o 'reproducer status' --capture --capture-path %t.repro | FileCheck %s --check-prefix OFF
+# RUN: LLDB_CAPTURE_REPRODUCER=0 %lldb -b -o 'reproducer status' --capture | FileCheck %s --check-prefix OFF
+# RUN: LLDB_CAPTURE_REPRODUCER=OFF %lldb -b -o 'reproducer status' --capture --capture-path %t.repro | FileCheck %s --check-prefix OFF
+# RUN: LLDB_CAPTURE_REPRODUCER=off %lldb -b -o 'reproducer status' --capture | FileCheck %s --check-prefix OFF
+
+# RUN: LLDB_CAPTURE_REPRODUCER=bogus %lldb -b -o 'reproducer status' --capture | FileCheck %s --check-prefix CAPTURE
+# RUN: LLDB_CAPTURE_REPRODUCER=bogus %lldb -b -o 'reproducer status' | FileCheck %s --check-prefix OFF
+
+# CAPTURE: Reproducer is in capture mode.
+# OFF: Reproducer is off.
diff --git a/lldb/test/Shell/Reproducer/lit.local.cfg b/lldb/test/Shell/Reproducer/lit.local.cfg
index 5659f1baa06d..7386b8655d1e 100644
--- a/lldb/test/Shell/Reproducer/lit.local.cfg
+++ b/lldb/test/Shell/Reproducer/lit.local.cfg
@@ -1,2 +1,3 @@
 # Enable crash reports for the reproducer tests.
 del config.environment['LLVM_DISABLE_CRASH_REPORT']
+del config.environment['LLDB_CAPTURE_REPRODUCER']