newlib-cygwin/winsup/cygwin/debug.cc

217 lines
5.1 KiB
C++

/* debug.cc
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include "cygerrno.h"
#ifdef DEBUGGING
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "cygheap.h"
#endif
#undef CloseHandle
#ifdef DEBUGGING
/* Here lies extra debugging routines which help track down internal
Cygwin problems when compiled with -DDEBUGGING . */
#define NFREEH (sizeof (cygheap->debug.freeh) / sizeof (cygheap->debug.freeh[0]))
class lock_debug
{
static NO_COPY SRWLOCK lock;
public:
lock_debug () { AcquireSRWLockExclusive (&lock); }
~lock_debug () { ReleaseSRWLockExclusive (&lock); }
};
SRWLOCK NO_COPY lock_debug::lock = SRWLOCK_INIT;
static bool mark_closed (const char *, int, HANDLE, const char *, bool);
/* Find a registered handle in the linked list of handles. */
static handle_list *
find_handle (HANDLE h)
{
handle_list *hl;
for (hl = &cygheap->debug.starth; hl->next != NULL; hl = hl->next)
if (hl->next->h == h)
goto out;
hl = NULL;
out:
return hl;
}
void
verify_handle (const char *func, int ln, HANDLE h)
{
lock_debug here;
handle_list *hl = find_handle (h);
if (!hl)
return;
system_printf ("%s:%d - multiple attempts to add handle %p", func, ln, h);
system_printf (" previously allocated by %s:%d(%s<%p>) winpid %d",
hl->func, hl->ln, hl->name, hl->h, hl->pid);
}
void
setclexec (HANDLE oh, HANDLE nh, bool not_inheriting)
{
lock_debug here;
handle_list *hl = find_handle (oh);
if (hl)
{
hl = hl->next;
hl->inherited = !not_inheriting;
hl->h = nh;
}
}
/* Create a new handle record */
static handle_list *
newh ()
{
handle_list *hl;
for (hl = cygheap->debug.freeh; hl < cygheap->debug.freeh + NFREEH; hl++)
if (hl->name == NULL)
return hl;
return NULL;
}
void
modify_handle (const char *func, int ln, HANDLE h, const char *name, bool inh)
{
lock_debug here;
handle_list *hl = find_handle (h);
if (!hl)
{
system_printf ("%s:%d handle %s<%p> not found", func, ln, name, h);
return;
}
hl->next->inherited = inh;
debug_printf ("%s:%d set handle %s<%p> inheritance flag to %d", func, ln,
name, h, inh);
}
/* Add a handle to the linked list of known handles. */
void
add_handle (const char *func, int ln, HANDLE h, const char *name, bool inh)
{
handle_list *hl;
if (!cygheap)
return;
lock_debug here;
if ((hl = find_handle (h)))
{
hl = hl->next;
if (hl->name == name && hl->func == func && hl->ln == ln)
return;
system_printf ("%s:%d - multiple attempts to add handle %s<%p>", func,
ln, name, h);
system_printf (" previously allocated by %s:%d(%s<%p>) winpid %d",
hl->func, hl->ln, hl->name, hl->h, hl->pid);
return;
}
if ((hl = newh ()) == NULL)
{
debug_printf ("couldn't allocate memory for %s(%d): %s(%p)",
func, ln, name, h);
return;
}
hl->h = h;
hl->name = name;
hl->func = func;
hl->ln = ln;
hl->inherited = inh;
hl->pid = GetCurrentProcessId ();
hl->next = cygheap->debug.starth.next;
cygheap->debug.starth.next = hl;
SetHandleInformation (h, HANDLE_FLAG_PROTECT_FROM_CLOSE, HANDLE_FLAG_PROTECT_FROM_CLOSE);
debug_printf ("protecting handle '%s'(%p), inherited flag %d", hl->name, hl->h, hl->inherited);
}
static void
delete_handle (handle_list *hl)
{
handle_list *hnuke = hl->next;
debug_printf ("nuking handle '%s' (%p)", hnuke->name, hnuke->h);
hl->next = hnuke->next;
memset (hnuke, 0, sizeof (*hnuke));
}
void
debug_fixup_after_fork_exec ()
{
/* No lock needed at this point */
handle_list *hl;
for (hl = &cygheap->debug.starth; hl->next != NULL; /* nothing */)
if (hl->next->inherited)
hl = hl->next;
else
delete_handle (hl); // removes hl->next
}
static bool
mark_closed (const char *func, int ln, HANDLE h, const char *name, bool force)
{
handle_list *hl;
if (!cygheap)
return true;
if ((hl = find_handle (h)) && !force)
{
hl = hl->next;
system_printf ("attempt to close protected handle %s:%d(%s<%p>) winpid %d",
hl->func, hl->ln, hl->name, hl->h, hl->pid);
system_printf (" by %s:%d(%s<%p>)", func, ln, name, h);
return false;
}
handle_list *hln;
if (hl && (hln = hl->next) && strcmp (name, hln->name) != 0)
{
system_printf ("closing protected handle %s:%d(%s<%p>)",
hln->func, hln->ln, hln->name, hln->h);
system_printf (" by %s:%d(%s<%p>)", func, ln, name, h);
}
if (hl)
delete_handle (hl);
return true;
}
/* Close a known handle. Complain if !force and closing a known handle or
if the name of the handle being closed does not match the registered name. */
bool
close_handle (const char *func, int ln, HANDLE h, const char *name, bool force)
{
bool ret;
lock_debug here;
if (!mark_closed (func, ln, h, name, force))
return false;
SetHandleInformation (h, HANDLE_FLAG_PROTECT_FROM_CLOSE, 0);
ret = CloseHandle (h);
if (!ret)
{
system_printf ("CloseHandle(%s<%p>) failed %s:%d, %E", name, h, func, ln);
try_to_debug ();
}
return ret;
}
#endif /*DEBUGGING*/