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-rw-r--r--gdb/linux-nat.c271
1 files changed, 16 insertions, 255 deletions
diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index db23433..46e3dbf 100644
--- a/gdb/linux-nat.c
+++ b/gdb/linux-nat.c
@@ -20,6 +20,8 @@
#include "defs.h"
#include "inferior.h"
#include "target.h"
+#include "nat/linux-nat.h"
+#include "nat/linux-waitpid.h"
#include "gdb_string.h"
#include "gdb_wait.h"
#include "gdb_assert.h"
@@ -171,11 +173,6 @@ blocked. */
#define O_LARGEFILE 0
#endif
-/* Unlike other extended result codes, WSTOPSIG (status) on
- PTRACE_O_TRACESYSGOOD syscall events doesn't return SIGTRAP, but
- instead SIGTRAP with bit 7 set. */
-#define SYSCALL_SIGTRAP (SIGTRAP | 0x80)
-
/* The single-threaded native GNU/Linux target_ops. We save a pointer for
the use of the multi-threaded target. */
static struct target_ops *linux_ops;
@@ -226,24 +223,6 @@ struct simple_pid_list
};
struct simple_pid_list *stopped_pids;
-/* This variable is a tri-state flag: -1 for unknown, 0 if PTRACE_O_TRACEFORK
- can not be used, 1 if it can. */
-
-static int linux_supports_tracefork_flag = -1;
-
-/* This variable is a tri-state flag: -1 for unknown, 0 if
- PTRACE_O_TRACESYSGOOD can not be used, 1 if it can. */
-
-static int linux_supports_tracesysgood_flag = -1;
-
-/* If we have PTRACE_O_TRACEFORK, this flag indicates whether we also have
- PTRACE_O_TRACEVFORKDONE. */
-
-static int linux_supports_tracevforkdone_flag = -1;
-
-/* Stores the current used ptrace() options. */
-static int current_ptrace_options = 0;
-
/* Async mode support. */
/* The read/write ends of the pipe registered as waitable file in the
@@ -349,244 +328,26 @@ pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
return 0;
}
-
-/* A helper function for linux_test_for_tracefork, called after fork (). */
-
-static void
-linux_tracefork_child (void)
-{
- ptrace (PTRACE_TRACEME, 0, 0, 0);
- kill (getpid (), SIGSTOP);
- fork ();
- _exit (0);
-}
-
-/* Wrapper function for waitpid which handles EINTR. */
-
-static int
-my_waitpid (int pid, int *statusp, int flags)
-{
- int ret;
-
- do
- {
- ret = waitpid (pid, statusp, flags);
- }
- while (ret == -1 && errno == EINTR);
-
- return ret;
-}
-
-/* Determine if PTRACE_O_TRACEFORK can be used to follow fork events.
-
- First, we try to enable fork tracing on ORIGINAL_PID. If this fails,
- we know that the feature is not available. This may change the tracing
- options for ORIGINAL_PID, but we'll be setting them shortly anyway.
-
- However, if it succeeds, we don't know for sure that the feature is
- available; old versions of PTRACE_SETOPTIONS ignored unknown options. We
- create a child process, attach to it, use PTRACE_SETOPTIONS to enable
- fork tracing, and let it fork. If the process exits, we assume that we
- can't use TRACEFORK; if we get the fork notification, and we can extract
- the new child's PID, then we assume that we can. */
+/* Initialize ptrace warnings and check for supported ptrace
+ features given PID. */
static void
-linux_test_for_tracefork (int original_pid)
+linux_init_ptrace (pid_t pid)
{
- int child_pid, ret, status;
- long second_pid;
-
- linux_supports_tracefork_flag = 0;
- linux_supports_tracevforkdone_flag = 0;
-
- ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACEFORK);
- if (ret != 0)
- return;
-
- child_pid = fork ();
- if (child_pid == -1)
- perror_with_name (("fork"));
-
- if (child_pid == 0)
- linux_tracefork_child ();
-
- ret = my_waitpid (child_pid, &status, 0);
- if (ret == -1)
- perror_with_name (("waitpid"));
- else if (ret != child_pid)
- error (_("linux_test_for_tracefork: waitpid: unexpected result %d."), ret);
- if (! WIFSTOPPED (status))
- error (_("linux_test_for_tracefork: waitpid: unexpected status %d."),
- status);
-
- ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, PTRACE_O_TRACEFORK);
- if (ret != 0)
- {
- ret = ptrace (PTRACE_KILL, child_pid, 0, 0);
- if (ret != 0)
- {
- warning (_("linux_test_for_tracefork: failed to kill child"));
- return;
- }
-
- ret = my_waitpid (child_pid, &status, 0);
- if (ret != child_pid)
- warning (_("linux_test_for_tracefork: failed "
- "to wait for killed child"));
- else if (!WIFSIGNALED (status))
- warning (_("linux_test_for_tracefork: unexpected "
- "wait status 0x%x from killed child"), status);
-
- return;
- }
-
- /* Check whether PTRACE_O_TRACEVFORKDONE is available. */
- ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0,
- PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORKDONE);
- linux_supports_tracevforkdone_flag = (ret == 0);
-
- ret = ptrace (PTRACE_CONT, child_pid, 0, 0);
- if (ret != 0)
- warning (_("linux_test_for_tracefork: failed to resume child"));
-
- ret = my_waitpid (child_pid, &status, 0);
-
- if (ret == child_pid && WIFSTOPPED (status)
- && status >> 16 == PTRACE_EVENT_FORK)
- {
- second_pid = 0;
- ret = ptrace (PTRACE_GETEVENTMSG, child_pid, 0, &second_pid);
- if (ret == 0 && second_pid != 0)
- {
- int second_status;
-
- linux_supports_tracefork_flag = 1;
- my_waitpid (second_pid, &second_status, 0);
- ret = ptrace (PTRACE_KILL, second_pid, 0, 0);
- if (ret != 0)
- warning (_("linux_test_for_tracefork: "
- "failed to kill second child"));
- my_waitpid (second_pid, &status, 0);
- }
- }
- else
- warning (_("linux_test_for_tracefork: unexpected result from waitpid "
- "(%d, status 0x%x)"), ret, status);
-
- do
- {
- ret = ptrace (PTRACE_KILL, child_pid, 0, 0);
- if (ret != 0)
- warning ("linux_test_for_tracefork: failed to kill child");
- my_waitpid (child_pid, &status, 0);
- }
- while (WIFSTOPPED (status));
-}
-
-/* Determine if PTRACE_O_TRACESYSGOOD can be used to follow syscalls.
-
- We try to enable syscall tracing on ORIGINAL_PID. If this fails,
- we know that the feature is not available. This may change the tracing
- options for ORIGINAL_PID, but we'll be setting them shortly anyway. */
-
-static void
-linux_test_for_tracesysgood (int original_pid)
-{
- int ret;
-
- linux_supports_tracesysgood_flag = 0;
-
- ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACESYSGOOD);
- if (ret != 0)
- return;
-
- linux_supports_tracesysgood_flag = 1;
-}
-
-/* Determine wether we support PTRACE_O_TRACESYSGOOD option available.
- This function also sets linux_supports_tracesysgood_flag. */
-
-static int
-linux_supports_tracesysgood (int pid)
-{
- if (linux_supports_tracesysgood_flag == -1)
- linux_test_for_tracesysgood (pid);
- return linux_supports_tracesysgood_flag;
-}
-
-/* Return non-zero iff we have tracefork functionality available.
- This function also sets linux_supports_tracefork_flag. */
-
-static int
-linux_supports_tracefork (int pid)
-{
- if (linux_supports_tracefork_flag == -1)
- linux_test_for_tracefork (pid);
- return linux_supports_tracefork_flag;
-}
-
-static int
-linux_supports_tracevforkdone (int pid)
-{
- if (linux_supports_tracefork_flag == -1)
- linux_test_for_tracefork (pid);
- return linux_supports_tracevforkdone_flag;
-}
-
-static void
-linux_enable_tracesysgood (ptid_t ptid)
-{
- int pid = ptid_get_lwp (ptid);
-
- if (pid == 0)
- pid = ptid_get_pid (ptid);
-
- if (linux_supports_tracesysgood (pid) == 0)
- return;
-
- current_ptrace_options |= PTRACE_O_TRACESYSGOOD;
-
- ptrace (PTRACE_SETOPTIONS, pid, 0, current_ptrace_options);
-}
-
-
-void
-linux_enable_event_reporting (ptid_t ptid)
-{
- int pid = ptid_get_lwp (ptid);
-
- if (pid == 0)
- pid = ptid_get_pid (ptid);
-
- if (! linux_supports_tracefork (pid))
- return;
-
- current_ptrace_options |= PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK
- | PTRACE_O_TRACEEXEC | PTRACE_O_TRACECLONE;
-
- if (linux_supports_tracevforkdone (pid))
- current_ptrace_options |= PTRACE_O_TRACEVFORKDONE;
-
- /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support
- read-only process state. */
-
- ptrace (PTRACE_SETOPTIONS, pid, 0, current_ptrace_options);
+ linux_enable_event_reporting (pid);
+ linux_ptrace_init_warnings ();
}
static void
linux_child_post_attach (int pid)
{
- linux_enable_event_reporting (pid_to_ptid (pid));
- linux_enable_tracesysgood (pid_to_ptid (pid));
- linux_ptrace_init_warnings ();
+ linux_init_ptrace (pid);
}
static void
linux_child_post_startup_inferior (ptid_t ptid)
{
- linux_enable_event_reporting (ptid);
- linux_enable_tracesysgood (ptid);
- linux_ptrace_init_warnings ();
+ linux_init_ptrace (ptid_get_pid (ptid));
}
/* Return the number of known LWPs in the tgid given by PID. */
@@ -772,9 +533,9 @@ holding the child stopped. Try \"set detach-on-fork\" or \
parent_inf->pspace->breakpoints_not_allowed = detach_fork;
parent_lp = find_lwp_pid (pid_to_ptid (parent_pid));
- gdb_assert (linux_supports_tracefork_flag >= 0);
+ gdb_assert (linux_supports_tracefork () >= 0);
- if (linux_supports_tracevforkdone (0))
+ if (linux_supports_tracevforkdone ())
{
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
@@ -945,7 +706,7 @@ holding the child stopped. Try \"set detach-on-fork\" or \
static int
linux_child_insert_fork_catchpoint (int pid)
{
- return !linux_supports_tracefork (pid);
+ return !linux_supports_tracefork ();
}
static int
@@ -957,7 +718,7 @@ linux_child_remove_fork_catchpoint (int pid)
static int
linux_child_insert_vfork_catchpoint (int pid)
{
- return !linux_supports_tracefork (pid);
+ return !linux_supports_tracefork ();
}
static int
@@ -969,7 +730,7 @@ linux_child_remove_vfork_catchpoint (int pid)
static int
linux_child_insert_exec_catchpoint (int pid)
{
- return !linux_supports_tracefork (pid);
+ return !linux_supports_tracefork ();
}
static int
@@ -982,7 +743,7 @@ static int
linux_child_set_syscall_catchpoint (int pid, int needed, int any_count,
int table_size, int *table)
{
- if (!linux_supports_tracesysgood (pid))
+ if (!linux_supports_tracesysgood ())
return 1;
/* On GNU/Linux, we ignore the arguments. It means that we only
@@ -1429,7 +1190,7 @@ lin_lwp_attach_lwp (ptid_t ptid)
if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0)
{
- if (linux_supports_tracefork_flag)
+ if (linux_supports_tracefork ())
{
/* If we haven't stopped all threads when we get here,
we may have seen a thread listed in thread_db's list,