Centralize the handling of attach permissions on linux in tests
Summary:
On linux we need the process to give us special permissions before we can attach to it.
Previously, the code for this was copied into every file that needed it. This moves the code to a
central place to reduce code duplication.
Reviewers: clayborg
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D15992
llvm-svn: 257319
diff --git a/lldb/packages/Python/lldbsuite/test/README-TestSuite b/lldb/packages/Python/lldbsuite/test/README-TestSuite
index 6df4d7b..70e4c91 100644
--- a/lldb/packages/Python/lldbsuite/test/README-TestSuite
+++ b/lldb/packages/Python/lldbsuite/test/README-TestSuite
@@ -157,3 +157,10 @@
then use SBInterpreter::HandleCommand to run the command. You get the full result text
from the command in the command return object, and all the part where you are driving the
debugger to the point you want to test will be more robust.
+
+o Attaching in test cases:
+
+ If you need to attach to inferiors in your tests, you must make sure the inferior calls
+ lldb_enable_attach(), before the debugger attempts to attach. This function performs any
+ platform-specific processing needed to enable attaching to this process (e.g., on Linux, we
+ execute prctl(PR_SET_TRACER) syscall to disable protections present in some Linux systems).
diff --git a/lldb/packages/Python/lldbsuite/test/driver/batch_mode/main.c b/lldb/packages/Python/lldbsuite/test/driver/batch_mode/main.c
index c1f1651..c85a0f2 100644
--- a/lldb/packages/Python/lldbsuite/test/driver/batch_mode/main.c
+++ b/lldb/packages/Python/lldbsuite/test/driver/batch_mode/main.c
@@ -2,25 +2,10 @@
#include <string.h>
#include <unistd.h>
-#if defined(__linux__)
-#include <sys/prctl.h>
-#endif
-
int
main (int argc, char **argv)
{
-#if defined(__linux__)
- // Immediately enable any ptracer so that we can allow the stub attach
- // operation to succeed. Some Linux kernels are locked down so that
- // only an ancestor process can be a ptracer of a process. This disables that
- // restriction. Without it, attach-related stub tests will fail.
-#if defined(PR_SET_PTRACER) && defined(PR_SET_PTRACER_ANY)
- // For now we execute on best effort basis. If this fails for
- // some reason, so be it.
- const int prctl_result = prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0);
- (void) prctl_result;
-#endif
-#endif
+ lldb_enable_attach();
int do_crash = 0;
int do_wait = 0;
diff --git a/lldb/packages/Python/lldbsuite/test/functionalities/attach_resume/main.cpp b/lldb/packages/Python/lldbsuite/test/functionalities/attach_resume/main.cpp
index 7cf3602..82aad70 100644
--- a/lldb/packages/Python/lldbsuite/test/functionalities/attach_resume/main.cpp
+++ b/lldb/packages/Python/lldbsuite/test/functionalities/attach_resume/main.cpp
@@ -4,10 +4,6 @@
#include <chrono>
#include <thread>
-#if defined(__linux__)
-#include <sys/prctl.h>
-#endif
-
volatile bool debugger_flag = true; // The debugger will flip this to false
void *start(void *data)
@@ -25,18 +21,7 @@
int main(int argc, char const *argv[])
{
-#if defined(__linux__)
- // Immediately enable any ptracer so that we can allow the stub attach
- // operation to succeed. Some Linux kernels are locked down so that
- // only an ancestor process can be a ptracer of a process. This disables that
- // restriction. Without it, attach-related stub tests will fail.
-#if defined(PR_SET_PTRACER) && defined(PR_SET_PTRACER_ANY)
- // For now we execute on best effort basis. If this fails for
- // some reason, so be it.
- const int prctl_result = prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0);
- static_cast<void> (prctl_result);
-#endif
-#endif
+ lldb_enable_attach();
static const size_t nthreads = 16;
std::thread threads[nthreads];
diff --git a/lldb/packages/Python/lldbsuite/test/functionalities/process_attach/main.cpp b/lldb/packages/Python/lldbsuite/test/functionalities/process_attach/main.cpp
index 8021fea..46ffacc 100644
--- a/lldb/packages/Python/lldbsuite/test/functionalities/process_attach/main.cpp
+++ b/lldb/packages/Python/lldbsuite/test/functionalities/process_attach/main.cpp
@@ -1,28 +1,11 @@
#include <stdio.h>
-#if defined(__linux__)
-#include <sys/prctl.h>
-#endif
-
#include <chrono>
#include <thread>
int main(int argc, char const *argv[]) {
int temp;
-#if defined(__linux__)
- // Immediately enable any ptracer so that we can allow the stub attach
- // operation to succeed. Some Linux kernels are locked down so that
- // only an ancestor process can be a ptracer of a process. This disables that
- // restriction. Without it, attach-related stub tests will fail.
-#if defined(PR_SET_PTRACER) && defined(PR_SET_PTRACER_ANY)
- int prctl_result;
-
- // For now we execute on best effort basis. If this fails for
- // some reason, so be it.
- prctl_result = prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0);
- (void) prctl_result;
-#endif
-#endif
+ lldb_enable_attach();
// Waiting to be attached by the debugger.
temp = 0;
diff --git a/lldb/packages/Python/lldbsuite/test/functionalities/process_group/main.c b/lldb/packages/Python/lldbsuite/test/functionalities/process_group/main.c
index c730c62..7e986bb 100644
--- a/lldb/packages/Python/lldbsuite/test/functionalities/process_group/main.c
+++ b/lldb/packages/Python/lldbsuite/test/functionalities/process_group/main.c
@@ -2,10 +2,6 @@
#include <unistd.h>
#include <sys/wait.h>
-#if defined(__linux__)
-#include <sys/prctl.h>
-#endif
-
volatile int release_child_flag = 0;
int main(int argc, char const *argv[])
@@ -61,18 +57,7 @@
}
else
{ // child
-#if defined(__linux__)
- // Immediately enable any ptracer so that we can allow the stub attach
- // operation to succeed. Some Linux kernels are locked down so that
- // only an ancestor process can be a ptracer of a process. This disables that
- // restriction. Without it, attach-related stub tests will fail.
-#if defined(PR_SET_PTRACER) && defined(PR_SET_PTRACER_ANY)
- // For now we execute on best effort basis. If this fails for
- // some reason, so be it.
- const int prctl_result = prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0);
- (void) prctl_result;
-#endif
-#endif
+ lldb_enable_attach();
while (! release_child_flag) // Wait for debugger to attach
sleep(1);
diff --git a/lldb/packages/Python/lldbsuite/test/functionalities/register/main.cpp b/lldb/packages/Python/lldbsuite/test/functionalities/register/main.cpp
index 876dd08..1565157 100644
--- a/lldb/packages/Python/lldbsuite/test/functionalities/register/main.cpp
+++ b/lldb/packages/Python/lldbsuite/test/functionalities/register/main.cpp
@@ -8,10 +8,6 @@
//===----------------------------------------------------------------------===//
#include <stdio.h>
-#if defined(__linux__)
-#include <sys/prctl.h>
-#endif
-
#include <chrono>
#include <thread>
@@ -19,18 +15,7 @@
int main (int argc, char const *argv[])
{
-#if defined(__linux__)
- // Immediately enable any ptracer so that we can allow the stub attach
- // operation to succeed. Some Linux kernels are locked down so that
- // only an ancestor process can be a ptracer of a process. This disables that
- // restriction. Without it, attach-related stub tests will fail.
-#if defined(PR_SET_PTRACER) && defined(PR_SET_PTRACER_ANY)
- // For now we execute on best effort basis. If this fails for
- // some reason, so be it.
- const int prctl_result = prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0);
- static_cast<void> (prctl_result);
-#endif
-#endif
+ lldb_enable_attach();
char my_string[] = {'a', 'b', 'c', 'd', 'e', 'f', 'g', 0};
double my_double = 1234.5678;
diff --git a/lldb/packages/Python/lldbsuite/test/functionalities/thread/create_after_attach/main.cpp b/lldb/packages/Python/lldbsuite/test/functionalities/thread/create_after_attach/main.cpp
index 8434458..d8f06e5 100644
--- a/lldb/packages/Python/lldbsuite/test/functionalities/thread/create_after_attach/main.cpp
+++ b/lldb/packages/Python/lldbsuite/test/functionalities/thread/create_after_attach/main.cpp
@@ -4,10 +4,6 @@
using std::chrono::microseconds;
-#if defined(__linux__)
-#include <sys/prctl.h>
-#endif
-
volatile int g_thread_2_continuing = 0;
void *
@@ -42,20 +38,7 @@
int main(int argc, char const *argv[])
{
-#if defined(__linux__)
- // Immediately enable any ptracer so that we can allow the stub attach
- // operation to succeed. Some Linux kernels are locked down so that
- // only an ancestor process can be a ptracer of a process. This disables that
- // restriction. Without it, attach-related stub tests will fail.
-#if defined(PR_SET_PTRACER) && defined(PR_SET_PTRACER_ANY)
- int prctl_result;
-
- // For now we execute on best effort basis. If this fails for
- // some reason, so be it.
- prctl_result = prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0);
- (void) prctl_result;
-#endif
-#endif
+ lldb_enable_attach();
// Create a new thread
std::thread thread_1(thread_1_func, nullptr);
diff --git a/lldb/packages/Python/lldbsuite/test/make/test_common.h b/lldb/packages/Python/lldbsuite/test/make/test_common.h
index 6f81970..39b8532 100644
--- a/lldb/packages/Python/lldbsuite/test/make/test_common.h
+++ b/lldb/packages/Python/lldbsuite/test/make/test_common.h
@@ -17,3 +17,28 @@
// declared. This may not be necessary after MSVC 12.
#include <eh.h>
#endif
+
+
+// On some systems (e.g., some versions of linux) it is not possible to attach to a process
+// without it giving us special permissions. This defines the lldb_enable_attach macro, which
+// should perform any such actions, if needed by the platform. This is a macro instead of a
+// function to avoid the need for complex linking of the test programs.
+#if defined(__linux__)
+#include <sys/prctl.h>
+
+#if defined(PR_SET_PTRACER) && defined(PR_SET_PTRACER_ANY)
+// For now we execute on best effort basis. If this fails for some reason, so be it.
+#define lldb_enable_attach() \
+ do \
+ { \
+ const int prctl_result = prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0); \
+ (void)prctl_result; \
+ } while (0)
+
+#endif
+
+#else // not linux
+
+#define lldb_enable_attach()
+
+#endif
diff --git a/lldb/packages/Python/lldbsuite/test/python_api/hello_world/main.c b/lldb/packages/Python/lldbsuite/test/python_api/hello_world/main.c
index 31a041e..1b942d0 100644
--- a/lldb/packages/Python/lldbsuite/test/python_api/hello_world/main.c
+++ b/lldb/packages/Python/lldbsuite/test/python_api/hello_world/main.c
@@ -1,25 +1,8 @@
#include <stdio.h>
-#if defined(__linux__)
-#include <sys/prctl.h>
-#endif
-
-int main(int argc, char const *argv[]) {
-
-#if defined(__linux__)
- // Immediately enable any ptracer so that we can allow the stub attach
- // operation to succeed. Some Linux kernels are locked down so that
- // only an ancestor process can be a ptracer of a process. This disables that
- // restriction. Without it, attach-related stub tests will fail.
-#if defined(PR_SET_PTRACER) && defined(PR_SET_PTRACER_ANY)
- int prctl_result;
-
- // For now we execute on best effort basis. If this fails for
- // some reason, so be it.
- prctl_result = prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0);
- (void) prctl_result;
-#endif
-#endif
+int main(int argc, char const *argv[])
+{
+ lldb_enable_attach();
printf("Hello world.\n"); // Set break point at this line.
if (argc == 1)
diff --git a/lldb/packages/Python/lldbsuite/test/tools/lldb-server/main.cpp b/lldb/packages/Python/lldbsuite/test/tools/lldb-server/main.cpp
index c65b225..b97c6eb 100644
--- a/lldb/packages/Python/lldbsuite/test/tools/lldb-server/main.cpp
+++ b/lldb/packages/Python/lldbsuite/test/tools/lldb-server/main.cpp
@@ -20,10 +20,6 @@
#include <sys/syscall.h>
#endif
-#if defined(__linux__)
-#include <sys/prctl.h>
-#endif
-
static const char *const RETVAL_PREFIX = "retval:";
static const char *const SLEEP_PREFIX = "sleep:";
static const char *const STDERR_PREFIX = "stderr:";
@@ -210,16 +206,7 @@
int main (int argc, char **argv)
{
-#if defined(__linux__)
- // Immediately enable any ptracer so that we can allow the stub attach
- // operation to succeed. Some Linux kernels are locked down so that
- // only an ancestor can be a ptracer of a process. This disables that
- // restriction. Without it, attach-related stub tests will fail.
-#if defined(PR_SET_PTRACER) && defined(PR_SET_PTRACER_ANY)
- const int prctl_result = prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0);
- static_cast<void> (prctl_result);
-#endif
-#endif
+ lldb_enable_attach();
std::vector<pthread_t> threads;
std::unique_ptr<uint8_t[]> heap_array_up;