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Drop using _tlsbase and _tlstop in favor of access via NtCurrentTeb.

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* cygtls.h (_tlsbase): Remove.  Replace throughout with
        NtCurrentTeb()->Tib.StackBase.
        (_tlstop): Remove. Replace throughout with
        NtCurrentTeb()->Tib.StackLimit.
        * dcrt0.cc (child_info_fork::alloc_stack): Move definition of local
        teb variable up to be used throughout.
        * include/cygwin/config.h (__getreent): Use inline function on both
        architectures.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This commit is contained in:
Corinna Vinschen
2015-12-02 12:11:06 +01:00
parent 8e6213210d
commit 7b0c063f12
7 changed files with 43 additions and 42 deletions
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28
winsup/cygwin/dcrt0.cc
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@@ -411,15 +411,16 @@ child_info_fork::alloc_stack ()
{
/* Make sure not to try a hard allocation if we have been forked off from
the main thread of a Cygwin process which has been started from a 64 bit
parent. In that case the _tlsbase of the forked child is not the same
as the _tlsbase of the parent (== stackbottom), but only because the
parent. In that case the StackBase of the forked child is not the same
as the StackBase of the parent (== stackbottom), but only because the
stack of the parent has been slightly rearranged. See comment in
wow64_revert_to_original_stack for details. We check here if the
parent stack fits into the child stack. */
if (_tlsbase != stackbottom
PTEB teb = NtCurrentTeb ();
if (teb->Tib.StackBase != stackbottom
&& (!wincap.is_wow64 ()
|| stacktop < NtCurrentTeb ()->DeallocationStack
|| stackbottom > _tlsbase))
|| stacktop < teb->DeallocationStack
|| stackbottom > teb->Tib.StackBase))
{
void *stack_ptr;
size_t stacksize;
@@ -432,10 +433,10 @@ child_info_fork::alloc_stack ()
stacksize = (PBYTE) stackbottom - (PBYTE) stackaddr;
if (!VirtualAlloc (stackaddr, stacksize, MEM_RESERVE, PAGE_NOACCESS))
{
PTEB teb = NtCurrentTeb ();
api_fatal ("fork: can't reserve memory for parent stack "
"%p - %p, (child has %p - %p), %E",
stackaddr, stackbottom, teb->DeallocationStack, _tlsbase);
stackaddr, stackbottom, teb->DeallocationStack,
teb->Tib.StackBase);
}
/* Commit the area commited in parent. */
stacksize = (PBYTE) stackbottom - (PBYTE) stacktop;
@@ -471,9 +472,10 @@ child_info_fork::alloc_stack ()
/* Fork has been called from main thread. Simply commit the region
of the stack commited in the parent but not yet commited in the
child and create new guardpages. */
if (_tlstop > stacktop)
if (NtCurrentTeb()->Tib.StackLimit > stacktop)
{
SIZE_T commitsize = (PBYTE) _tlstop - (PBYTE) stacktop;
SIZE_T commitsize = (PBYTE) NtCurrentTeb()->Tib.StackLimit
- (PBYTE) stacktop;
if (!VirtualAlloc (stacktop, commitsize, MEM_COMMIT, PAGE_READWRITE))
api_fatal ("can't commit child memory for stack %p(%ly), %E",
stacktop, commitsize);
@@ -482,14 +484,14 @@ child_info_fork::alloc_stack ()
MEM_COMMIT, PAGE_READWRITE | PAGE_GUARD))
api_fatal ("fork: couldn't allocate new stack guard page %p, %E",
guardpage);
_tlstop = stacktop;
NtCurrentTeb()->Tib.StackLimit = stacktop;
}
stackaddr = 0;
/* This only affects forked children of a process started from a native
64 bit process, but it doesn't hurt to do it unconditionally. Fix
StackBase in the child to be the same as in the parent, so that the
computation of _my_tls is correct. */
_tlsbase = (PVOID) stackbottom;
teb->Tib.StackBase = (PVOID) stackbottom;
}
}
@@ -918,8 +920,8 @@ dll_crt0_1 (void *)
this step. */
if (fork_info->stackaddr)
{
_tlsbase = (PVOID) fork_info->stackbottom;
_tlstop = (PVOID) fork_info->stacktop;
NtCurrentTeb()->Tib.StackBase = (PVOID) fork_info->stackbottom;
NtCurrentTeb()->Tib.StackLimit = (PVOID) fork_info->stacktop;
}
/* Not resetting _my_tls.incyg here because presumably fork will overwrite