tls.c

Bug Summary

File:	thread/tls.c
Warning:	line 86, column 13 Using a fixed address is not portable because that address will probably not be valid in all environments or platforms

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-unknown-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name tls.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -fhalf-no-semantic-interposition -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/home/isvv/naviserver/nsthread -resource-dir /usr/local/lib/clang/15.0.0 -D _FORTIFY_SOURCE=2 -D NDEBUG -D SYSTEM_MALLOC -I ../include -I /usr/include/tcl8.6 -D HAVE_CONFIG_H -internal-isystem /usr/local/lib/clang/15.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/11/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -std=c99 -fdebug-compilation-dir=/home/isvv/naviserver/nsthread -ferror-limit 19 -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-checker alpha -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2022-07-23-130959-11103-1 -x c tls.c

1/*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://mozilla.org/.
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
* the License for the specific language governing rights and limitations
* under the License.
*
* The Original Code is AOLserver Code and related documentation
* distributed by AOL.
*
* The Initial Developer of the Original Code is America Online,
* Inc. Portions created by AOL are Copyright (C) 1999 America Online,
* Inc. All Rights Reserved.
*
* Alternatively, the contents of this file may be used under the terms
* of the GNU General Public License (the "GPL"), in which case the
* provisions of GPL are applicable instead of those above.  If you wish
* to allow use of your version of this file only under the terms of the
* GPL and not to allow others to use your version of this file under the
* License, indicate your decision by deleting the provisions above and
* replace them with the notice and other provisions required by the GPL.
* If you do not delete the provisions above, a recipient may use your
* version of this file under either the License or the GPL.
*/


31/*
* tls.c --
*
*      Thread local storage support for nsthreads.  Note that the nsthread
*      library handles thread local storage directly.
*/

38#include "thread.h"

40/*
* The following global variable specifies the maximum TLS id.  Modifying
* this value has no effect.
*/

45static uintptr_t nsThreadMaxTls = NS_THREAD_MAXTLS100;

47/*
* Static functions defined in this file.
*/

51static Ns_TlsCleanup *cleanupProcs[NS_THREAD_MAXTLS100];

53
54/*
*----------------------------------------------------------------------
*
* Ns_TlsAlloc --
*
*      Allocate the next tls id.
*
* Results:
*      None.
*
* Side effects:
*      Id is set in given tlsPtr.
*
*----------------------------------------------------------------------
*/

70void
71Ns_TlsAlloc(Ns_Tls *keyPtr, Ns_TlsCleanup *cleanup)
72{
  static uintptr_t nextkey = 1u;
  uintptr_t        key;

  NS_NONNULL_ASSERT(keyPtr != NULL)((void) (0));

  Ns_MasterLock();
  if (nextkey == nsThreadMaxTls) {
1
Assuming 'nextkey' is not equal to 'nsThreadMaxTls'→
2
←
Taking false branch→
      Tcl_Panic("Ns_TlsAlloc: exceeded max tls: %" PRIuPTR"l" "u", nsThreadMaxTls);
  }
  key = nextkey++;
  cleanupProcs[key] = cleanup;
  Ns_MasterUnlock();

  *keyPtr = (void *) key;
3
←
Using a fixed address is not portable because that address will probably not be valid in all environments or platforms
87}

89
90/*
*----------------------------------------------------------------------
*
* Ns_TlsSet --
*
*      Set the value for a threads tls slot.
*
* Results:
*      None.
*
* Side effects:
*      None.
*
*----------------------------------------------------------------------
*/

106void
107Ns_TlsSet(const Ns_Tls *keyPtr, void *value)
108{
  uintptr_t   key;

  NS_NONNULL_ASSERT(keyPtr != NULL)((void) (0));

  key = (uintptr_t) *keyPtr;
  if (key < 1 || key >= NS_THREAD_MAXTLS100) {
      Tcl_Panic("Ns_TlsSet: invalid key: %" PRIuPTR"l" "u"
                ": should be between 1 and %" PRIuPTR"l" "u",
                key, nsThreadMaxTls);
  } else {
      void **slots = NsGetTls();

      slots[key] = value;
  }
123}

125
126/*
*----------------------------------------------------------------------
*
* Ns_TlsGet --
*
*      Get this thread's value in a tls slot.
*
* Results:
*      Pointer in slot.
*
* Side effects:
*      None.
*
*----------------------------------------------------------------------
*/

142void *
143Ns_TlsGet(const Ns_Tls *keyPtr)
144{
  uintptr_t  key;
  void      *result;

  NS_NONNULL_ASSERT(keyPtr != NULL)((void) (0));

  key = (uintptr_t) *keyPtr;
  if (key < 1 || key >= NS_THREAD_MAXTLS100) {
      result = NULL((void*)0);
      Tcl_Panic("Ns_TlsGet: invalid key: %" PRIuPTR"l" "u"
                ": should be between 1 and %" PRIuPTR"l" "u",
                key, nsThreadMaxTls);
  } else {
      void  **slots = NsGetTls();

      result = slots[key];
  }
  return result;
162}

164
165/*
*----------------------------------------------------------------------
*
* NsCleanupTls --
*
*      Cleanup thread local storage in LIFO order for an exiting thread.
*      Note the careful use of the counters to keep iterating over the
*      list, up to 5 times, until all TLS values are NULL.  This emulates
*      the Pthread TLS behavior which catches a destructor inadvertently
*      calling a library which resets a TLS value after it has been destroyed.
*
* Results:
*      None.
*
* Side effects:
*      Cleanup procs are invoked for non-null values.
*
*----------------------------------------------------------------------
*/

185void
186NsCleanupTls(void **slots)
187{
  NS_NONNULL_ASSERT(slots != NULL)((void) (0));

  if (
191#if defined(TCL_IS_FIXED)
      1
193#else
      NS_finalshutdown != 1
195#endif
      ) {
      int tries, retry;

      tries = 0;
      do {
          int i;

          retry = 0;
          i = NS_THREAD_MAXTLS100;
          while (i-- > 0) {
              if (cleanupProcs[i] != NULL((void*)0) && slots[i] != NULL((void*)0)) {
                  void *arg;

                  arg = slots[i];
                  slots[i] = NULL((void*)0);
                  (*cleanupProcs[i])(arg);
                  retry = 1;
              }
          }
      } while (retry && tries++ < 5);
  }
217}

219/*
* Local Variables:
* mode: c
* c-basic-offset: 4
* fill-column: 78
* indent-tabs-mode: nil
* End:
*/