[PATCH v2] Disable get_ptrace_pid for NetBSD

Kamil Rytarowski
2020-03-18T21:56:24Z

Unlike most other Operating Systems, NetBSD tracks both pid and lwp.
The process id on NetBSD is stored always in the pid field of ptid.

gdb/ChangeLog:

* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
* inf-ptrace.c: Likewise.
* (gdb_ptrace): Add.
* (inf_ptrace_target::resume): Update.
* (inf_ptrace_target::xfer_partial): Likewise.
---
gdb/ChangeLog | 8 ++++++++
gdb/inf-ptrace.c | 34 ++++++++++++++++++++++++----------
gdb/inf-ptrace.h | 2 ++
3 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 84964dc00ac..406414cee76 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,11 @@
+2020-03-18 Kamil Rytarowski <n54@gmx.com>
+
+ * inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
+ * inf-ptrace.c: Likewise.
+ * (gdb_ptrace): Add.
+ * (inf_ptrace_target::resume): Update.
+ * (inf_ptrace_target::xfer_partial): Likewise.
+
2020-03-17 Kamil Rytarowski <n54@gmx.com>

* regformats/regdef.h: Put reg in gdb namespace.
diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index db17a76d946..931192bd0db 100644
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -37,6 +37,18 @@

\f

+static int
+gdb_ptrace (PTRACE_TYPE_ARG1 request, ptid_t ptid, PTRACE_TYPE_ARG3 addr,
+ PTRACE_TYPE_ARG4 data)
+{
+#ifdef __NetBSD__
+ return ptrace (request, ptid.pid (), addr, data);
+#else
+ pid_t pid = get_ptrace_pid (ptid);
+ return ptrace (request, pid, addr, data);
+#endif
+}
+
/* A unique_ptr helper to unpush a target. */

struct target_unpusher
@@ -313,8 +325,12 @@ inf_ptrace_target::kill ()
target_mourn_inferior (inferior_ptid);
}

+#ifndef __NetBSD__
/* Return which PID to pass to ptrace in order to observe/control the
- tracee identified by PTID. */
+ tracee identified by PTID.
+
+ Unlike most other Operating Systems, NetBSD tracks both pid and lwp
+ and avoids this function. */

pid_t
get_ptrace_pid (ptid_t ptid)
@@ -328,6 +344,7 @@ get_ptrace_pid (ptid_t ptid)
pid = ptid.pid ();
return pid;
}
+#endif

/* Resume execution of thread PTID, or all threads if PTID is -1. If
STEP is nonzero, single-step it. If SIGNAL is nonzero, give it
@@ -336,15 +353,12 @@ get_ptrace_pid (ptid_t ptid)
void
inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
{
- pid_t pid;
int request;

if (minus_one_ptid == ptid)
/* Resume all threads. Traditionally ptrace() only supports
single-threaded processes, so simply resume the inferior. */
- pid = inferior_ptid.pid ();
- else
- pid = get_ptrace_pid (ptid);
+ ptid = inferior_ptid;

if (catch_syscall_enabled () > 0)
request = PT_SYSCALL;
@@ -365,7 +379,7 @@ inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
where it was. If GDB wanted it to start some other way, we have
already written a new program counter value to the child. */
errno = 0;
- ptrace (request, pid, (PTRACE_TYPE_ARG3)1, gdb_signal_to_host (signal));
+ gdb_ptrace (request, ptid, (PTRACE_TYPE_ARG3)1, gdb_signal_to_host (signal));
if (errno != 0)
perror_with_name (("ptrace"));
}
@@ -528,7 +542,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
const gdb_byte *writebuf,
ULONGEST offset, ULONGEST len, ULONGEST *xfered_len)
{
- pid_t pid = get_ptrace_pid (inferior_ptid);
+ ptid_t ptid = inferior_ptid;

switch (object)
{
@@ -552,7 +566,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
piod.piod_len = len;

errno = 0;
- if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
+ if (gdb_ptrace (PT_IO, ptid, (caddr_t)&piod, 0) == 0)
{
/* Return the actual number of bytes read or written. */
*xfered_len = piod.piod_len;
@@ -565,7 +579,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
return TARGET_XFER_EOF;
}
#endif
- *xfered_len = inf_ptrace_peek_poke (pid, readbuf, writebuf,
+ *xfered_len = inf_ptrace_peek_poke (ptid.pid (), readbuf, writebuf,
offset, len);
return *xfered_len != 0 ? TARGET_XFER_OK : TARGET_XFER_EOF;

@@ -588,7 +602,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
piod.piod_len = len;

errno = 0;
- if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
+ if (gdb_ptrace (PT_IO, ptid, (caddr_t)&piod, 0) == 0)
{
/* Return the actual number of bytes read or written. */
*xfered_len = piod.piod_len;
diff --git a/gdb/inf-ptrace.h b/gdb/inf-ptrace.h
index dd0733736f2..340d41d8beb 100644
--- a/gdb/inf-ptrace.h
+++ b/gdb/inf-ptrace.h
@@ -78,9 +78,11 @@ struct inf_ptrace_target : public inf_child_target
void detach_success (inferior *inf);
};

+#ifndef __NetBSD__
/* Return which PID to pass to ptrace in order to observe/control the
tracee identified by PTID. */

extern pid_t get_ptrace_pid (ptid_t);
+#endif

#endif
--
2.25.0