[binutils-gdb] Add support for NetBSD threads in amd64-bsd-nat.c

[Kamil Rytarowski <krytarowski@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=1c0aa1fbb2fb1920c12400940704ee90491b7290

commit 1c0aa1fbb2fb1920c12400940704ee90491b7290
Author: Kamil Rytarowski <n54@gmx.com>
Date:   Sat Mar 14 17:41:11 2020 +0100

    Add support for NetBSD threads in amd64-bsd-nat.c
    
    NetBSD ptrace(2) accepts thread id (LWP) as the 4th argument for threads.
    
    Define gdb_ptrace() a wrapper function for ptrace(2) that properly passes
    the pid,lwp pair on NetBSD and the result of get_ptrace_pid() for others.
    
    gdb/ChangeLog:
    
            * amd64-bsd-nat.c (gdb_ptrace): New.
            * (amd64bsd_fetch_inferior_registers,
            amd64bsd_store_inferior_registers) Switch from pid_t to ptid_t.
            * (amd64bsd_fetch_inferior_registers,
            amd64bsd_store_inferior_registers) Use gdb_ptrace.

Diff:
---
 gdb/ChangeLog       |  8 ++++++++
 gdb/amd64-bsd-nat.c | 47 +++++++++++++++++++++++++++++++----------------
 2 files changed, 39 insertions(+), 16 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 24093684000..f4f7b796601 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,11 @@
+2020-03-17  Kamil Rytarowski  <n54@gmx.com>
+
+	* amd64-bsd-nat.c (gdb_ptrace): New.
+	* (amd64bsd_fetch_inferior_registers,
+	amd64bsd_store_inferior_registers) Switch from pid_t to ptid_t.
+	* (amd64bsd_fetch_inferior_registers,
+	amd64bsd_store_inferior_registers) Use gdb_ptrace.
+
 2020-03-17  Kamil Rytarowski  <n54@gmx.com>
 
 	* user-regs.c (user_reg::read): Rename to...
diff --git a/gdb/amd64-bsd-nat.c b/gdb/amd64-bsd-nat.c
index 9a3c9c22c05..1ff044ff470 100644
--- a/gdb/amd64-bsd-nat.c
+++ b/gdb/amd64-bsd-nat.c
@@ -36,6 +36,21 @@
 #include "amd64-bsd-nat.h"
 \f
 
+static int
+gdb_ptrace (PTRACE_TYPE_ARG1 request, ptid_t ptid, PTRACE_TYPE_ARG3 addr,
+	    PTRACE_TYPE_ARG4 data)
+{
+#ifdef __NetBSD__
+  gdb_assert (data == 0);
+  /* Support for NetBSD threads: unlike other ptrace implementations in this
+     file, NetBSD requires that we pass both the pid and lwp.  */
+  return ptrace (request, ptid.pid (), addr, ptid.lwp ());
+#else
+  pid_t pid = get_ptrace_pid (ptid);
+  return ptrace (request, pid, addr, data);
+#endif
+}
+
 /* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
    for all registers (including the floating-point registers).  */
 
@@ -43,7 +58,7 @@ void
 amd64bsd_fetch_inferior_registers (struct regcache *regcache, int regnum)
 {
   struct gdbarch *gdbarch = regcache->arch ();
-  pid_t pid = get_ptrace_pid (regcache->ptid ());
+  ptid_t ptid = regcache->ptid ();
 #if defined(PT_GETFSBASE) || defined(PT_GETGSBASE)
   const struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 #endif
@@ -52,7 +67,7 @@ amd64bsd_fetch_inferior_registers (struct regcache *regcache, int regnum)
     {
       struct reg regs;
 
-      if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
+      if (gdb_ptrace (PT_GETREGS, ptid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 	perror_with_name (_("Couldn't get registers"));
 
       amd64_supply_native_gregset (regcache, &regs, -1);
@@ -65,7 +80,7 @@ amd64bsd_fetch_inferior_registers (struct regcache *regcache, int regnum)
     {
       register_t base;
 
-      if (ptrace (PT_GETFSBASE, pid, (PTRACE_TYPE_ARG3) &base, 0) == -1)
+      if (gdb_ptrace (PT_GETFSBASE, ptid, (PTRACE_TYPE_ARG3) &base, 0) == -1)
 	perror_with_name (_("Couldn't get segment register fs_base"));
 
       regcache->raw_supply (tdep->fsbase_regnum, &base);
@@ -78,7 +93,7 @@ amd64bsd_fetch_inferior_registers (struct regcache *regcache, int regnum)
     {
       register_t base;
 
-      if (ptrace (PT_GETGSBASE, pid, (PTRACE_TYPE_ARG3) &base, 0) == -1)
+      if (gdb_ptrace (PT_GETGSBASE, ptid, (PTRACE_TYPE_ARG3) &base, 0) == -1)
 	perror_with_name (_("Couldn't get segment register gs_base"));
 
       regcache->raw_supply (tdep->fsbase_regnum + 1, &base);
@@ -96,7 +111,7 @@ amd64bsd_fetch_inferior_registers (struct regcache *regcache, int regnum)
       if (x86bsd_xsave_len != 0)
 	{
 	  xstateregs = alloca (x86bsd_xsave_len);
-	  if (ptrace (PT_GETXSTATE, pid, (PTRACE_TYPE_ARG3) xstateregs, 0)
+	  if (gdb_ptrace (PT_GETXSTATE, ptid, (PTRACE_TYPE_ARG3) xstateregs, 0)
 	      == -1)
 	    perror_with_name (_("Couldn't get extended state status"));
 
@@ -105,7 +120,7 @@ amd64bsd_fetch_inferior_registers (struct regcache *regcache, int regnum)
 	}
 #endif
 
-      if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
+      if (gdb_ptrace (PT_GETFPREGS, ptid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 	perror_with_name (_("Couldn't get floating point status"));
 
       amd64_supply_fxsave (regcache, -1, &fpregs);
@@ -119,7 +134,7 @@ void
 amd64bsd_store_inferior_registers (struct regcache *regcache, int regnum)
 {
   struct gdbarch *gdbarch = regcache->arch ();
-  pid_t pid = get_ptrace_pid (regcache->ptid ());
+  ptid_t ptid = regcache->ptid ();
 #if defined(PT_SETFSBASE) || defined(PT_SETGSBASE)
   const struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 #endif
@@ -128,12 +143,12 @@ amd64bsd_store_inferior_registers (struct regcache *regcache, int regnum)
     {
       struct reg regs;
 
-      if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
+      if (gdb_ptrace (PT_GETREGS, ptid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
         perror_with_name (_("Couldn't get registers"));
 
       amd64_collect_native_gregset (regcache, &regs, regnum);
 
-      if (ptrace (PT_SETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
+      if (gdb_ptrace (PT_SETREGS, ptid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
         perror_with_name (_("Couldn't write registers"));
 
       if (regnum != -1)
@@ -149,7 +164,7 @@ amd64bsd_store_inferior_registers (struct regcache *regcache, int regnum)
       base = 0;
       regcache->raw_collect (tdep->fsbase_regnum, &base);
 
-      if (ptrace (PT_SETFSBASE, pid, (PTRACE_TYPE_ARG3) &base, 0) == -1)
+      if (gdb_ptrace (PT_SETFSBASE, ptid, (PTRACE_TYPE_ARG3) &base, 0) == -1)
 	perror_with_name (_("Couldn't write segment register fs_base"));
       if (regnum != -1)
 	return;
@@ -164,7 +179,7 @@ amd64bsd_store_inferior_registers (struct regcache *regcache, int regnum)
       base = 0;
       regcache->raw_collect (tdep->fsbase_regnum + 1, &base);
 
-      if (ptrace (PT_SETGSBASE, pid, (PTRACE_TYPE_ARG3) &base, 0) == -1)
+      if (gdb_ptrace (PT_SETGSBASE, ptid, (PTRACE_TYPE_ARG3) &base, 0) == -1)
 	perror_with_name (_("Couldn't write segment register gs_base"));
       if (regnum != -1)
 	return;
@@ -180,25 +195,25 @@ amd64bsd_store_inferior_registers (struct regcache *regcache, int regnum)
       if (x86bsd_xsave_len != 0)
 	{
 	  xstateregs = alloca (x86bsd_xsave_len);
-	  if (ptrace (PT_GETXSTATE, pid, (PTRACE_TYPE_ARG3) xstateregs, 0)
+	  if (gdb_ptrace (PT_GETXSTATE, ptid, (PTRACE_TYPE_ARG3) xstateregs, 0)
 	      == -1)
 	    perror_with_name (_("Couldn't get extended state status"));
 
 	  amd64_collect_xsave (regcache, regnum, xstateregs, 0);
 
-	  if (ptrace (PT_SETXSTATE, pid, (PTRACE_TYPE_ARG3) xstateregs,
-		      x86bsd_xsave_len) == -1)
+	  if (gdb_ptrace (PT_SETXSTATE, ptid, (PTRACE_TYPE_ARG3) xstateregs,
+			  x86bsd_xsave_len) == -1)
 	    perror_with_name (_("Couldn't write extended state status"));
 	  return;
 	}
 #endif
 
-      if (ptrace (PT_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
+      if (gdb_ptrace (PT_GETFPREGS, ptid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 	perror_with_name (_("Couldn't get floating point status"));
 
       amd64_collect_fxsave (regcache, regnum, &fpregs);
 
-      if (ptrace (PT_SETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
+      if (gdb_ptrace (PT_SETFPREGS, ptid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 	perror_with_name (_("Couldn't write floating point status"));
     }
 }