yann@96
|
1 |
Status: submitted for comments
|
yann@96
|
2 |
|
yann@96
|
3 |
2004-11-12 Daniel Jacobowitz <dan@debian.org>
|
yann@96
|
4 |
|
yann@96
|
5 |
* linux-nat.c (my_waitpid): New function.
|
yann@96
|
6 |
(linux_test_for_tracefork): Make more robust and verbose. Take
|
yann@96
|
7 |
an ORIGINAL_PID argument and test for PTRACE_SETOPTIONS first.
|
yann@96
|
8 |
(linux_supports_tracefork, linux_supports_tracevforkdone): Take a PID
|
yann@96
|
9 |
argument. Update calls to linux_test_for_tracefork.
|
yann@96
|
10 |
(linux_enable_event_reporting, child_follow_fork)
|
yann@96
|
11 |
(child_insert_fork_catchpoint, child_insert_vfork_catchpoint)
|
yann@96
|
12 |
(child_insert_exec_catchpoint): Update calls to
|
yann@96
|
13 |
linux_supports_tracefork and linux_supports_tracevforkdone.
|
yann@96
|
14 |
|
yann@96
|
15 |
Index: gdb-6.3/gdb/linux-nat.c
|
yann@96
|
16 |
===================================================================
|
yann@96
|
17 |
--- gdb-6.3.orig/gdb/linux-nat.c 2004-10-08 16:29:47.000000000 -0400
|
yann@96
|
18 |
+++ gdb-6.3/gdb/linux-nat.c 2004-11-13 16:41:51.368720845 -0500
|
yann@96
|
19 |
@@ -150,18 +150,47 @@ linux_tracefork_child (void)
|
yann@96
|
20 |
exit (0);
|
yann@96
|
21 |
}
|
yann@96
|
22 |
|
yann@96
|
23 |
-/* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. We
|
yann@96
|
24 |
+/* Wrapper function for waitpid which handles EINTR. */
|
yann@96
|
25 |
+
|
yann@96
|
26 |
+static int
|
yann@96
|
27 |
+my_waitpid (int pid, int *status, int flags)
|
yann@96
|
28 |
+{
|
yann@96
|
29 |
+ int ret;
|
yann@96
|
30 |
+ do
|
yann@96
|
31 |
+ {
|
yann@96
|
32 |
+ ret = waitpid (pid, status, flags);
|
yann@96
|
33 |
+ }
|
yann@96
|
34 |
+ while (ret == -1 && errno == EINTR);
|
yann@96
|
35 |
+
|
yann@96
|
36 |
+ return ret;
|
yann@96
|
37 |
+}
|
yann@96
|
38 |
+
|
yann@96
|
39 |
+/* Determine if PTRACE_O_TRACEFORK can be used to follow fork events.
|
yann@96
|
40 |
+
|
yann@96
|
41 |
+ First, we try to enable fork tracing on ORIGINAL_PID. If this fails,
|
yann@96
|
42 |
+ we know that the feature is not available. This may change the tracing
|
yann@96
|
43 |
+ options for ORIGINAL_PID, but we'll be setting them shortly anyway.
|
yann@96
|
44 |
+
|
yann@96
|
45 |
+ However, if it succeeds, we don't know for sure that the feature is
|
yann@96
|
46 |
+ available; old versions of PTRACE_SETOPTIONS ignored unknown options. We
|
yann@96
|
47 |
create a child process, attach to it, use PTRACE_SETOPTIONS to enable
|
yann@96
|
48 |
- fork tracing, and let it fork. If the process exits, we assume that
|
yann@96
|
49 |
- we can't use TRACEFORK; if we get the fork notification, and we can
|
yann@96
|
50 |
- extract the new child's PID, then we assume that we can. */
|
yann@96
|
51 |
+ fork tracing, and let it fork. If the process exits, we assume that we
|
yann@96
|
52 |
+ can't use TRACEFORK; if we get the fork notification, and we can extract
|
yann@96
|
53 |
+ the new child's PID, then we assume that we can. */
|
yann@96
|
54 |
|
yann@96
|
55 |
static void
|
yann@96
|
56 |
-linux_test_for_tracefork (void)
|
yann@96
|
57 |
+linux_test_for_tracefork (int original_pid)
|
yann@96
|
58 |
{
|
yann@96
|
59 |
int child_pid, ret, status;
|
yann@96
|
60 |
long second_pid;
|
yann@96
|
61 |
|
yann@96
|
62 |
+ linux_supports_tracefork_flag = 0;
|
yann@96
|
63 |
+ linux_supports_tracevforkdone_flag = 0;
|
yann@96
|
64 |
+
|
yann@96
|
65 |
+ ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACEFORK);
|
yann@96
|
66 |
+ if (ret != 0)
|
yann@96
|
67 |
+ return;
|
yann@96
|
68 |
+
|
yann@96
|
69 |
child_pid = fork ();
|
yann@96
|
70 |
if (child_pid == -1)
|
yann@96
|
71 |
perror_with_name ("linux_test_for_tracefork: fork");
|
yann@96
|
72 |
@@ -169,7 +198,7 @@ linux_test_for_tracefork (void)
|
yann@96
|
73 |
if (child_pid == 0)
|
yann@96
|
74 |
linux_tracefork_child ();
|
yann@96
|
75 |
|
yann@96
|
76 |
- ret = waitpid (child_pid, &status, 0);
|
yann@96
|
77 |
+ ret = my_waitpid (child_pid, &status, 0);
|
yann@96
|
78 |
if (ret == -1)
|
yann@96
|
79 |
perror_with_name ("linux_test_for_tracefork: waitpid");
|
yann@96
|
80 |
else if (ret != child_pid)
|
yann@96
|
81 |
@@ -177,13 +206,23 @@ linux_test_for_tracefork (void)
|
yann@96
|
82 |
if (! WIFSTOPPED (status))
|
yann@96
|
83 |
error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status);
|
yann@96
|
84 |
|
yann@96
|
85 |
- linux_supports_tracefork_flag = 0;
|
yann@96
|
86 |
-
|
yann@96
|
87 |
ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, PTRACE_O_TRACEFORK);
|
yann@96
|
88 |
if (ret != 0)
|
yann@96
|
89 |
{
|
yann@96
|
90 |
- ptrace (PTRACE_KILL, child_pid, 0, 0);
|
yann@96
|
91 |
- waitpid (child_pid, &status, 0);
|
yann@96
|
92 |
+ ret = ptrace (PTRACE_KILL, child_pid, 0, 0);
|
yann@96
|
93 |
+ if (ret != 0)
|
yann@96
|
94 |
+ {
|
yann@96
|
95 |
+ warning ("linux_test_for_tracefork: failed to kill child");
|
yann@96
|
96 |
+ return;
|
yann@96
|
97 |
+ }
|
yann@96
|
98 |
+
|
yann@96
|
99 |
+ ret = my_waitpid (child_pid, &status, 0);
|
yann@96
|
100 |
+ if (ret != child_pid)
|
yann@96
|
101 |
+ warning ("linux_test_for_tracefork: failed to wait for killed child");
|
yann@96
|
102 |
+ else if (!WIFSIGNALED (status))
|
yann@96
|
103 |
+ warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
|
yann@96
|
104 |
+ "killed child", status);
|
yann@96
|
105 |
+
|
yann@96
|
106 |
return;
|
yann@96
|
107 |
}
|
yann@96
|
108 |
|
yann@96
|
109 |
@@ -192,8 +231,12 @@ linux_test_for_tracefork (void)
|
yann@96
|
110 |
PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORKDONE);
|
yann@96
|
111 |
linux_supports_tracevforkdone_flag = (ret == 0);
|
yann@96
|
112 |
|
yann@96
|
113 |
- ptrace (PTRACE_CONT, child_pid, 0, 0);
|
yann@96
|
114 |
- ret = waitpid (child_pid, &status, 0);
|
yann@96
|
115 |
+ ret = ptrace (PTRACE_CONT, child_pid, 0, 0);
|
yann@96
|
116 |
+ if (ret != 0)
|
yann@96
|
117 |
+ warning ("linux_test_for_tracefork: failed to resume child");
|
yann@96
|
118 |
+
|
yann@96
|
119 |
+ ret = my_waitpid (child_pid, &status, 0);
|
yann@96
|
120 |
+
|
yann@96
|
121 |
if (ret == child_pid && WIFSTOPPED (status)
|
yann@96
|
122 |
&& status >> 16 == PTRACE_EVENT_FORK)
|
yann@96
|
123 |
{
|
yann@96
|
124 |
@@ -204,34 +247,38 @@ linux_test_for_tracefork (void)
|
yann@96
|
125 |
int second_status;
|
yann@96
|
126 |
|
yann@96
|
127 |
linux_supports_tracefork_flag = 1;
|
yann@96
|
128 |
- waitpid (second_pid, &second_status, 0);
|
yann@96
|
129 |
- ptrace (PTRACE_DETACH, second_pid, 0, 0);
|
yann@96
|
130 |
+ my_waitpid (second_pid, &second_status, 0);
|
yann@96
|
131 |
+ ret = ptrace (PTRACE_KILL, second_pid, 0, 0);
|
yann@96
|
132 |
+ if (ret != 0)
|
yann@96
|
133 |
+ warning ("linux_test_for_tracefork: failed to kill second child");
|
yann@96
|
134 |
}
|
yann@96
|
135 |
}
|
yann@96
|
136 |
+ else
|
yann@96
|
137 |
+ warning ("linux_test_for_tracefork: unexpected result from waitpid "
|
yann@96
|
138 |
+ "(%d, status 0x%x)", ret, status);
|
yann@96
|
139 |
|
yann@96
|
140 |
- if (WIFSTOPPED (status))
|
yann@96
|
141 |
- {
|
yann@96
|
142 |
- ptrace (PTRACE_DETACH, child_pid, 0, 0);
|
yann@96
|
143 |
- waitpid (child_pid, &status, 0);
|
yann@96
|
144 |
- }
|
yann@96
|
145 |
+ ret = ptrace (PTRACE_KILL, child_pid, 0, 0);
|
yann@96
|
146 |
+ if (ret != 0)
|
yann@96
|
147 |
+ warning ("linux_test_for_tracefork: failed to kill child");
|
yann@96
|
148 |
+ my_waitpid (child_pid, &status, 0);
|
yann@96
|
149 |
}
|
yann@96
|
150 |
|
yann@96
|
151 |
/* Return non-zero iff we have tracefork functionality available.
|
yann@96
|
152 |
This function also sets linux_supports_tracefork_flag. */
|
yann@96
|
153 |
|
yann@96
|
154 |
static int
|
yann@96
|
155 |
-linux_supports_tracefork (void)
|
yann@96
|
156 |
+linux_supports_tracefork (int pid)
|
yann@96
|
157 |
{
|
yann@96
|
158 |
if (linux_supports_tracefork_flag == -1)
|
yann@96
|
159 |
- linux_test_for_tracefork ();
|
yann@96
|
160 |
+ linux_test_for_tracefork (pid);
|
yann@96
|
161 |
return linux_supports_tracefork_flag;
|
yann@96
|
162 |
}
|
yann@96
|
163 |
|
yann@96
|
164 |
static int
|
yann@96
|
165 |
-linux_supports_tracevforkdone (void)
|
yann@96
|
166 |
+linux_supports_tracevforkdone (int pid)
|
yann@96
|
167 |
{
|
yann@96
|
168 |
if (linux_supports_tracefork_flag == -1)
|
yann@96
|
169 |
- linux_test_for_tracefork ();
|
yann@96
|
170 |
+ linux_test_for_tracefork (pid);
|
yann@96
|
171 |
return linux_supports_tracevforkdone_flag;
|
yann@96
|
172 |
}
|
yann@96
|
173 |
|
yann@96
|
174 |
@@ -242,12 +289,12 @@ linux_enable_event_reporting (ptid_t pti
|
yann@96
|
175 |
int pid = ptid_get_pid (ptid);
|
yann@96
|
176 |
int options;
|
yann@96
|
177 |
|
yann@96
|
178 |
- if (! linux_supports_tracefork ())
|
yann@96
|
179 |
+ if (! linux_supports_tracefork (pid))
|
yann@96
|
180 |
return;
|
yann@96
|
181 |
|
yann@96
|
182 |
options = PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK | PTRACE_O_TRACEEXEC
|
yann@96
|
183 |
| PTRACE_O_TRACECLONE;
|
yann@96
|
184 |
- if (linux_supports_tracevforkdone ())
|
yann@96
|
185 |
+ if (linux_supports_tracevforkdone (pid))
|
yann@96
|
186 |
options |= PTRACE_O_TRACEVFORKDONE;
|
yann@96
|
187 |
|
yann@96
|
188 |
/* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support
|
yann@96
|
189 |
@@ -308,7 +355,8 @@ child_follow_fork (int follow_child)
|
yann@96
|
190 |
|
yann@96
|
191 |
if (has_vforked)
|
yann@96
|
192 |
{
|
yann@96
|
193 |
- if (linux_supports_tracevforkdone ())
|
yann@96
|
194 |
+ gdb_assert (linux_supports_tracefork_flag >= 0);
|
yann@96
|
195 |
+ if (linux_supports_tracevforkdone (0))
|
yann@96
|
196 |
{
|
yann@96
|
197 |
int status;
|
yann@96
|
198 |
|
yann@96
|
199 |
@@ -476,7 +524,7 @@ linux_handle_extended_wait (int pid, int
|
yann@96
|
200 |
int
|
yann@96
|
201 |
child_insert_fork_catchpoint (int pid)
|
yann@96
|
202 |
{
|
yann@96
|
203 |
- if (! linux_supports_tracefork ())
|
yann@96
|
204 |
+ if (! linux_supports_tracefork (pid))
|
yann@96
|
205 |
error ("Your system does not support fork catchpoints.");
|
yann@96
|
206 |
|
yann@96
|
207 |
return 0;
|
yann@96
|
208 |
@@ -485,7 +533,7 @@ child_insert_fork_catchpoint (int pid)
|
yann@96
|
209 |
int
|
yann@96
|
210 |
child_insert_vfork_catchpoint (int pid)
|
yann@96
|
211 |
{
|
yann@96
|
212 |
- if (!linux_supports_tracefork ())
|
yann@96
|
213 |
+ if (!linux_supports_tracefork (pid))
|
yann@96
|
214 |
error ("Your system does not support vfork catchpoints.");
|
yann@96
|
215 |
|
yann@96
|
216 |
return 0;
|
yann@96
|
217 |
@@ -494,7 +542,7 @@ child_insert_vfork_catchpoint (int pid)
|
yann@96
|
218 |
int
|
yann@96
|
219 |
child_insert_exec_catchpoint (int pid)
|
yann@96
|
220 |
{
|
yann@96
|
221 |
- if (!linux_supports_tracefork ())
|
yann@96
|
222 |
+ if (!linux_supports_tracefork (pid))
|
yann@96
|
223 |
error ("Your system does not support exec catchpoints.");
|
yann@96
|
224 |
|
yann@96
|
225 |
return 0;
|