diff options
Diffstat (limited to 'gdb/nat/linux-ptrace.c')
| -rw-r--r-- | gdb/nat/linux-ptrace.c | 85 |
1 files changed, 31 insertions, 54 deletions
diff --git a/gdb/nat/linux-ptrace.c b/gdb/nat/linux-ptrace.c index aba3da8..fb12606 100644 --- a/gdb/nat/linux-ptrace.c +++ b/gdb/nat/linux-ptrace.c @@ -25,14 +25,10 @@ #include <stdint.h> -/* Stores the currently supported ptrace options. A value of - -1 means we did not check for features yet. A value of 0 means - there are no supported features. */ -static int current_ptrace_options = -1; - -/* Additional flags to test. */ - -static int additional_flags; +/* Stores the ptrace options supported by the running kernel. + A value of -1 means we did not check for features yet. A value + of 0 means there are no supported features. */ +static int supported_ptrace_options = -1; /* Find all possible reasons we could fail to attach PID and append these as strings to the already initialized BUFFER. '\0' @@ -343,7 +339,7 @@ linux_check_ptrace_features (void) int child_pid, ret, status; /* Initialize the options. */ - current_ptrace_options = 0; + supported_ptrace_options = 0; /* Fork a child so we can do some testing. The child will call linux_child_function and will get traced. The child will @@ -387,14 +383,11 @@ linux_test_for_tracesysgood (int child_pid) { int ret; - if ((additional_flags & PTRACE_O_TRACESYSGOOD) == 0) - return; - ret = ptrace (PTRACE_SETOPTIONS, child_pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) PTRACE_O_TRACESYSGOOD); if (ret == 0) - current_ptrace_options |= PTRACE_O_TRACESYSGOOD; + supported_ptrace_options |= PTRACE_O_TRACESYSGOOD; } /* Determine if PTRACE_O_TRACEFORK can be used to follow fork @@ -414,15 +407,12 @@ linux_test_for_tracefork (int child_pid) if (ret != 0) return; - if ((additional_flags & PTRACE_O_TRACEVFORKDONE) != 0) - { - /* Check if the target supports PTRACE_O_TRACEVFORKDONE. */ - ret = ptrace (PTRACE_SETOPTIONS, child_pid, (PTRACE_TYPE_ARG3) 0, - (PTRACE_TYPE_ARG4) (PTRACE_O_TRACEFORK - | PTRACE_O_TRACEVFORKDONE)); - if (ret == 0) - current_ptrace_options |= PTRACE_O_TRACEVFORKDONE; - } + /* Check if the target supports PTRACE_O_TRACEVFORKDONE. */ + ret = ptrace (PTRACE_SETOPTIONS, child_pid, (PTRACE_TYPE_ARG3) 0, + (PTRACE_TYPE_ARG4) (PTRACE_O_TRACEFORK + | PTRACE_O_TRACEVFORKDONE)); + if (ret == 0) + supported_ptrace_options |= PTRACE_O_TRACEVFORKDONE; /* Setting PTRACE_O_TRACEFORK did not cause an error, however we don't know for sure that the feature is available; old @@ -458,10 +448,10 @@ linux_test_for_tracefork (int child_pid) /* We got the PID from the grandchild, which means fork tracing is supported. */ - current_ptrace_options |= PTRACE_O_TRACECLONE; - current_ptrace_options |= (additional_flags & (PTRACE_O_TRACEFORK - | PTRACE_O_TRACEVFORK - | PTRACE_O_TRACEEXEC)); + supported_ptrace_options |= PTRACE_O_TRACECLONE; + supported_ptrace_options |= (PTRACE_O_TRACEFORK + | PTRACE_O_TRACEVFORK + | PTRACE_O_TRACEEXEC); /* Do some cleanup and kill the grandchild. */ my_waitpid (second_pid, &second_status, 0); @@ -489,33 +479,31 @@ linux_test_for_exitkill (int child_pid) (PTRACE_TYPE_ARG4) PTRACE_O_EXITKILL); if (ret == 0) - current_ptrace_options |= PTRACE_O_EXITKILL; + supported_ptrace_options |= PTRACE_O_EXITKILL; } /* Enable reporting of all currently supported ptrace events. - ATTACHED should be nonzero if we have attached to the inferior. */ + OPTIONS is a bit mask of extended features we want enabled, + if supported by the kernel. PTRACE_O_TRACECLONE is always + enabled, if supported. */ void -linux_enable_event_reporting (pid_t pid, int attached) +linux_enable_event_reporting (pid_t pid, int options) { - int ptrace_options; - /* Check if we have initialized the ptrace features for this target. If not, do it now. */ - if (current_ptrace_options == -1) + if (supported_ptrace_options == -1) linux_check_ptrace_features (); - ptrace_options = current_ptrace_options; - if (attached) - { - /* When attached to our inferior, we do not want the inferior - to die with us if we terminate unexpectedly. */ - ptrace_options &= ~PTRACE_O_EXITKILL; - } + /* We always want clone events. */ + options |= PTRACE_O_TRACECLONE; + + /* Filter out unsupported options. */ + options &= supported_ptrace_options; /* Set the options. */ ptrace (PTRACE_SETOPTIONS, pid, (PTRACE_TYPE_ARG3) 0, - (PTRACE_TYPE_ARG4) (uintptr_t) ptrace_options); + (PTRACE_TYPE_ARG4) (uintptr_t) options); } /* Disable reporting of all currently supported ptrace events. */ @@ -528,16 +516,16 @@ linux_disable_event_reporting (pid_t pid) } /* Returns non-zero if PTRACE_OPTIONS is contained within - CURRENT_PTRACE_OPTIONS, therefore supported. Returns 0 + SUPPORTED_PTRACE_OPTIONS, therefore supported. Returns 0 otherwise. */ static int ptrace_supports_feature (int ptrace_options) { - if (current_ptrace_options == -1) + if (supported_ptrace_options == -1) linux_check_ptrace_features (); - return ((current_ptrace_options & ptrace_options) == ptrace_options); + return ((supported_ptrace_options & ptrace_options) == ptrace_options); } /* Returns non-zero if PTRACE_EVENT_FORK is supported by ptrace, @@ -595,17 +583,6 @@ linux_ptrace_init_warnings (void) linux_ptrace_test_ret_to_nx (); } -/* Set additional ptrace flags to use. Some such flags may be checked - by the implementation above. This function must be called before - any other function in this file; otherwise the flags may not take - effect appropriately. */ - -void -linux_ptrace_set_additional_flags (int flags) -{ - additional_flags = flags; -} - /* Extract extended ptrace event from wait status. */ int |