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-rw-r--r--htl/Makefile1
-rw-r--r--htl/semaphoreP.h21
-rw-r--r--nptl/Makefile2
-rw-r--r--nptl/semaphoreP.h21
-rw-r--r--sysdeps/pthread/sem_close.c56
-rw-r--r--sysdeps/pthread/sem_open.c116
-rw-r--r--sysdeps/pthread/sem_routines.c187
-rw-r--r--sysdeps/pthread/sem_routines.h27
8 files changed, 223 insertions, 208 deletions
diff --git a/htl/Makefile b/htl/Makefile
index 9adc95e07f..c15c1b194e 100644
--- a/htl/Makefile
+++ b/htl/Makefile
@@ -131,6 +131,7 @@ libpthread-routines := pt-attr pt-attr-destroy pt-attr-getdetachstate	    \
 	sem_close sem-destroy sem-getvalue sem-init sem_open		    \
 	sem-post sem-timedwait sem-trywait sem_unlink			    \
 	sem-wait sem-waitfast						    \
+	sem_routines							    \
 									    \
 	cancellation							    \
 	cthreads-compat							    \
diff --git a/htl/semaphoreP.h b/htl/semaphoreP.h
index 3d6efcdec7..4b13f7b30d 100644
--- a/htl/semaphoreP.h
+++ b/htl/semaphoreP.h
@@ -21,27 +21,6 @@
 
 #define SEM_SHM_PREFIX  "sem."
 
-/* Keeping track of currently used mappings.  */
-struct inuse_sem
-{
-  dev_t dev;
-  ino_t ino;
-  int refcnt;
-  sem_t *sem;
-  char name[];
-};
-
-
-/* The search tree for existing mappings.  */
-extern void *__sem_mappings attribute_hidden;
-
-/* Lock to protect the search tree.  */
-extern int __sem_mappings_lock attribute_hidden;
-
-
-/* Comparison function for search in tree with existing mappings.  */
-extern int __sem_search (const void *a, const void *b) attribute_hidden;
-
 static inline void __new_sem_open_init (struct new_sem *sem, unsigned value)
 {
   /* This always is a shared semaphore.  */
diff --git a/nptl/Makefile b/nptl/Makefile
index c49134b936..8fb7fee6db 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -137,7 +137,7 @@ libpthread-routines = nptl-init nptlfreeres vars events version pt-interp \
 		      pthread_once \
 		      old_pthread_atfork \
 		      pthread_getcpuclockid \
-		      sem_init sem_destroy \
+		      sem_init sem_destroy sem_routines \
 		      sem_open sem_close sem_unlink \
 		      sem_getvalue \
 		      sem_wait sem_timedwait sem_clockwait sem_post \
diff --git a/nptl/semaphoreP.h b/nptl/semaphoreP.h
index 3585af09fc..1b786149f4 100644
--- a/nptl/semaphoreP.h
+++ b/nptl/semaphoreP.h
@@ -22,27 +22,6 @@
 
 #define SEM_SHM_PREFIX  "sem."
 
-/* Keeping track of currently used mappings.  */
-struct inuse_sem
-{
-  dev_t dev;
-  ino_t ino;
-  int refcnt;
-  sem_t *sem;
-  char name[];
-};
-
-
-/* The search tree for existing mappings.  */
-extern void *__sem_mappings attribute_hidden;
-
-/* Lock to protect the search tree.  */
-extern int __sem_mappings_lock attribute_hidden;
-
-
-/* Comparison function for search in tree with existing mappings.  */
-extern int __sem_search (const void *a, const void *b) attribute_hidden;
-
 static inline void __new_sem_open_init (struct new_sem *sem, unsigned value)
 {
 #if __HAVE_64B_ATOMICS
diff --git a/sysdeps/pthread/sem_close.c b/sysdeps/pthread/sem_close.c
index 8b6c9c6dc5..6649196cac 100644
--- a/sysdeps/pthread/sem_close.c
+++ b/sysdeps/pthread/sem_close.c
@@ -17,65 +17,17 @@
    <https://www.gnu.org/licenses/>.  */
 
 #include <errno.h>
-#include <search.h>
-#include <sys/mman.h>
 #include "semaphoreP.h"
-
-struct walk_closure
-{
-  sem_t *the_sem;
-  struct inuse_sem *rec;
-};
-
-static void
-walker (const void *inodep, VISIT which, void *closure0)
-{
-  struct walk_closure *closure = closure0;
-  struct inuse_sem *nodep = *(struct inuse_sem **) inodep;
-
-  if (nodep->sem == closure->the_sem)
-    closure->rec = nodep;
-}
-
+#include <sem_routines.h>
 
 int
 sem_close (sem_t *sem)
 {
-  int result = 0;
-
-  /* Get the lock.  */
-  lll_lock (__sem_mappings_lock, LLL_PRIVATE);
-
-  /* Locate the entry for the mapping the caller provided.  */
-  struct inuse_sem *rec;
-  {
-    struct walk_closure closure = { .the_sem = sem, .rec = NULL };
-    __twalk_r (__sem_mappings, walker, &closure);
-    rec = closure.rec;
-  }
-  if  (rec != NULL)
+  if (!__sem_remove_mapping (sem))
     {
-      /* Check the reference counter.  If it is going to be zero, free
-	 all the resources.  */
-      if (--rec->refcnt == 0)
-	{
-	  /* Remove the record from the tree.  */
-	  (void) __tdelete (rec, &__sem_mappings, __sem_search);
-
-	  result = munmap (rec->sem, sizeof (sem_t));
-
-	  free (rec);
-	}
-    }
-  else
-    {
-      /* This is no valid semaphore.  */
-      result = -1;
       __set_errno (EINVAL);
+      return -1;
     }
 
-  /* Release the lock.  */
-  lll_unlock (__sem_mappings_lock, LLL_PRIVATE);
-
-  return result;
+  return 0;
 }
diff --git a/sysdeps/pthread/sem_open.c b/sysdeps/pthread/sem_open.c
index d666414f32..028d76a685 100644
--- a/sysdeps/pthread/sem_open.c
+++ b/sysdeps/pthread/sem_open.c
@@ -16,127 +16,17 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include <errno.h>
 #include <fcntl.h>
-#include <pthread.h>
-#include <search.h>
 #include <semaphore.h>
 #include <stdarg.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
 #include <unistd.h>
 #include <sys/mman.h>
-#include <sys/stat.h>
 #include "semaphoreP.h"
 #include <shm-directory.h>
+#include <sem_routines.h>
 #include <futex-internal.h>
 #include <libc-lock.h>
 
-/* Comparison function for search of existing mapping.  */
-int
-attribute_hidden
-__sem_search (const void *a, const void *b)
-{
-  const struct inuse_sem *as = (const struct inuse_sem *) a;
-  const struct inuse_sem *bs = (const struct inuse_sem *) b;
-
-  if (as->ino != bs->ino)
-    /* Cannot return the difference the type is larger than int.  */
-    return as->ino < bs->ino ? -1 : (as->ino == bs->ino ? 0 : 1);
-
-  if (as->dev != bs->dev)
-    /* Cannot return the difference the type is larger than int.  */
-    return as->dev < bs->dev ? -1 : (as->dev == bs->dev ? 0 : 1);
-
-  return strcmp (as->name, bs->name);
-}
-
-
-/* The search tree for existing mappings.  */
-void *__sem_mappings attribute_hidden;
-
-/* Lock to protect the search tree.  */
-int __sem_mappings_lock attribute_hidden = LLL_LOCK_INITIALIZER;
-
-
-/* Search for existing mapping and if possible add the one provided.  */
-static sem_t *
-check_add_mapping (const char *name, int fd, sem_t *existing)
-{
-  size_t namelen = strlen (name);
-  sem_t *result = SEM_FAILED;
-
-  /* Get the information about the file.  */
-  struct stat64 st;
-  if (__fstat64 (fd, &st) == 0)
-    {
-      /* Get the lock.  */
-      lll_lock (__sem_mappings_lock, LLL_PRIVATE);
-
-      /* Search for an existing mapping given the information we have.  */
-      struct inuse_sem *fake;
-      fake = (struct inuse_sem *) alloca (sizeof (*fake) + namelen);
-      memcpy (fake->name, name, namelen);
-      fake->dev = st.st_dev;
-      fake->ino = st.st_ino;
-
-      struct inuse_sem **foundp = __tfind (fake, &__sem_mappings,
-					   __sem_search);
-      if (foundp != NULL)
-	{
-	  /* There is already a mapping.  Use it.  */
-	  result = (*foundp)->sem;
-	  ++(*foundp)->refcnt;
-	}
-      else
-	{
-	  /* We haven't found a mapping.  Install ione.  */
-	  struct inuse_sem *newp;
-
-	  newp = (struct inuse_sem *) malloc (sizeof (*newp) + namelen);
-	  if (newp != NULL)
-	    {
-	      /* If the caller hasn't provided any map it now.  */
-	      if (existing == SEM_FAILED)
-		existing = (sem_t *) mmap (NULL, sizeof (sem_t),
-					   PROT_READ | PROT_WRITE, MAP_SHARED,
-					   fd, 0);
-
-	      newp->dev = st.st_dev;
-	      newp->ino = st.st_ino;
-	      newp->refcnt = 1;
-	      newp->sem = existing;
-	      memcpy (newp->name, name, namelen);
-
-	      /* Insert the new value.  */
-	      if (existing != MAP_FAILED
-		  && __tsearch (newp, &__sem_mappings, __sem_search) != NULL)
-		/* Successful.  */
-		result = existing;
-	      else
-		/* Something went wrong while inserting the new
-		   value.  We fail completely.  */
-		free (newp);
-	    }
-	}
-
-      /* Release the lock.  */
-      lll_unlock (__sem_mappings_lock, LLL_PRIVATE);
-    }
-
-  if (result != existing && existing != SEM_FAILED && existing != MAP_FAILED)
-    {
-      /* Do not disturb errno.  */
-      int save = errno;
-      munmap (existing, sizeof (sem_t));
-      errno = save;
-    }
-
-  return result;
-}
-
-
 sem_t *
 sem_open (const char *name, int oflag, ...)
 {
@@ -183,7 +73,7 @@ sem_open (const char *name, int oflag, ...)
       else
 	/* Check whether we already have this semaphore mapped and
 	   create one if necessary.  */
-	result = check_add_mapping (name, fd, SEM_FAILED);
+	result = __sem_check_add_mapping (name, fd, SEM_FAILED);
     }
   else
     {
@@ -294,7 +184,7 @@ sem_open (const char *name, int oflag, ...)
 	    /* Insert the mapping into the search tree.  This also
 	       determines whether another thread sneaked by and already
 	       added such a mapping despite the fact that we created it.  */
-	    result = check_add_mapping (name, fd, result);
+	    result = __sem_check_add_mapping (name, fd, result);
 	}
 
       /* Now remove the temporary name.  This should never fail.  If
diff --git a/sysdeps/pthread/sem_routines.c b/sysdeps/pthread/sem_routines.c
new file mode 100644
index 0000000000..78d9364ebd
--- /dev/null
+++ b/sysdeps/pthread/sem_routines.c
@@ -0,0 +1,187 @@
+/* Helper code for POSIX semaphore implementation.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <search.h>
+#include <semaphoreP.h>
+#include <sys/mman.h>
+#include <sem_routines.h>
+
+/* Keeping track of currently used mappings.  */
+struct inuse_sem
+{
+  dev_t dev;
+  ino_t ino;
+  int refcnt;
+  sem_t *sem;
+  char name[];
+};
+
+/* Comparison function for search of existing mapping.  */
+static int
+sem_search (const void *a, const void *b)
+{
+  const struct inuse_sem *as = (const struct inuse_sem *) a;
+  const struct inuse_sem *bs = (const struct inuse_sem *) b;
+
+  if (as->ino != bs->ino)
+    /* Cannot return the difference the type is larger than int.  */
+    return as->ino < bs->ino ? -1 : (as->ino == bs->ino ? 0 : 1);
+
+  if (as->dev != bs->dev)
+    /* Cannot return the difference the type is larger than int.  */
+    return as->dev < bs->dev ? -1 : (as->dev == bs->dev ? 0 : 1);
+
+  return strcmp (as->name, bs->name);
+}
+
+/* The search tree for existing mappings.  */
+static void *sem_mappings;
+
+/* Lock to protect the search tree.  */
+static int sem_mappings_lock = LLL_LOCK_INITIALIZER;
+
+
+/* Search for existing mapping and if possible add the one provided.  */
+sem_t *
+__sem_check_add_mapping (const char *name, int fd, sem_t *existing)
+{
+  size_t namelen = strlen (name);
+  sem_t *result = SEM_FAILED;
+
+  /* Get the information about the file.  */
+  struct stat64 st;
+  if (__fstat64 (fd, &st) == 0)
+    {
+      /* Get the lock.  */
+      lll_lock (sem_mappings_lock, LLL_PRIVATE);
+
+      /* Search for an existing mapping given the information we have.  */
+      struct inuse_sem *fake;
+      fake = (struct inuse_sem *) alloca (sizeof (*fake) + namelen);
+      memcpy (fake->name, name, namelen);
+      fake->dev = st.st_dev;
+      fake->ino = st.st_ino;
+
+      struct inuse_sem **foundp = __tfind (fake, &sem_mappings, sem_search);
+      if (foundp != NULL)
+	{
+	  /* There is already a mapping.  Use it.  */
+	  result = (*foundp)->sem;
+	  ++(*foundp)->refcnt;
+	}
+      else
+	{
+	  /* We haven't found a mapping.  Install ione.  */
+	  struct inuse_sem *newp;
+
+	  newp = (struct inuse_sem *) malloc (sizeof (*newp) + namelen);
+	  if (newp != NULL)
+	    {
+	      /* If the caller hasn't provided any map it now.  */
+	      if (existing == SEM_FAILED)
+		existing = (sem_t *) mmap (NULL, sizeof (sem_t),
+					   PROT_READ | PROT_WRITE, MAP_SHARED,
+					   fd, 0);
+
+	      newp->dev = st.st_dev;
+	      newp->ino = st.st_ino;
+	      newp->refcnt = 1;
+	      newp->sem = existing;
+	      memcpy (newp->name, name, namelen);
+
+	      /* Insert the new value.  */
+	      if (existing != MAP_FAILED
+		  && __tsearch (newp, &sem_mappings, sem_search) != NULL)
+		/* Successful.  */
+		result = existing;
+	      else
+		/* Something went wrong while inserting the new
+		   value.  We fail completely.  */
+		free (newp);
+	    }
+	}
+
+      /* Release the lock.  */
+      lll_unlock (sem_mappings_lock, LLL_PRIVATE);
+    }
+
+  if (result != existing && existing != SEM_FAILED && existing != MAP_FAILED)
+    {
+      /* Do not disturb errno.  */
+      int save = errno;
+      munmap (existing, sizeof (sem_t));
+      errno = save;
+    }
+
+  return result;
+}
+
+struct walk_closure
+{
+  sem_t *the_sem;
+  struct inuse_sem *rec;
+};
+
+static void
+walker (const void *inodep, VISIT which, void *closure0)
+{
+  struct walk_closure *closure = closure0;
+  struct inuse_sem *nodep = *(struct inuse_sem **) inodep;
+
+  if (nodep->sem == closure->the_sem)
+    closure->rec = nodep;
+}
+
+bool
+__sem_remove_mapping (sem_t *sem)
+{
+  bool ret = true;
+
+  /* Get the lock.  */
+  lll_lock (sem_mappings_lock, LLL_PRIVATE);
+
+  /* Locate the entry for the mapping the caller provided.  */
+  struct inuse_sem *rec;
+  {
+    struct walk_closure closure = { .the_sem = sem, .rec = NULL };
+    __twalk_r (sem_mappings, walker, &closure);
+    rec = closure.rec;
+  }
+  if (rec != NULL)
+    {
+      /* Check the reference counter.  If it is going to be zero, free
+	 all the resources.  */
+      if (--rec->refcnt == 0)
+	{
+	  /* Remove the record from the tree.  */
+	  __tdelete (rec, &sem_mappings, sem_search);
+
+	  if (munmap (rec->sem, sizeof (sem_t)) == -1)
+	    ret = false;
+
+	  free (rec);
+	}
+    }
+  else
+    ret = false;
+
+  /* Release the lock.  */
+  lll_unlock (sem_mappings_lock, LLL_PRIVATE);
+
+  return ret;
+}
diff --git a/sysdeps/pthread/sem_routines.h b/sysdeps/pthread/sem_routines.h
new file mode 100644
index 0000000000..25d3e880ea
--- /dev/null
+++ b/sysdeps/pthread/sem_routines.h
@@ -0,0 +1,27 @@
+/* Helper code for POSIX semaphore implementation.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SEM_ROUTINES_H
+#define _SEM_ROUTINES_H
+
+sem_t * __sem_check_add_mapping (const char *name, int fd, sem_t *existing)
+  attribute_hidden;
+
+bool __sem_remove_mapping (sem_t *sem) attribute_hidden;
+
+#endif