source3/libsmb/libsmb_thread_impl.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    SMB client library implementation
   4    Copyright (C) Derrell Lipman 2009
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "libsmbclient.h"
  22 #include "libsmb_internal.h"
  23
  24
  25 /**
  26  * Initialize for an arbitrary thread implementation. The caller should
  27  * provide, as parameters, pointers to functions to implement the requisite
  28  * low-level thread functionality. A function must be provided for each
  29  * parameter; none may be null.
  30  *
  31  * If the thread implementation is POSIX Threads (pthreads), then the much
  32  * simpler smbc_thread_pthread() function may be used instead of this one.
  33  *
  34  * @param create_mutex
  35  *   Create a mutex. This function should expect three parameters: lockname,
  36  *   pplock, and location. It should create a unique mutex for each unique
  37  *   lockname it is provided, and return the mutex identifier in *pplock. The
  38  *   location parameter can be used for debugging, as it contains the
  39  *   compiler-provided __location__ of the call.
  40  *
  41  * @param destroy_mutex
  42  *   Destroy a mutex. This function should expect two parameters: plock and
  43  *   location. It should destroy the mutex associated with the identifier
  44  *   plock. The location parameter can be used for debugging, as it contains
  45  *   the compiler-provided __location__ of the call.
  46  *
  47  * @param lock_mutex
  48  *   Lock a mutex. This function should expect three parameters: plock,
  49  *   lock_type, and location. The mutex aassociated with identifier plock
  50  *   should be locked if lock_type is 1, and unlocked if lock_type is 2. The
  51  *   location parameter can be used for debugging, as it contains the
  52  *   compiler-provided __location__ of the call.
  53  *
  54  * @param create_tls
  55  *   Create thread local storage. This function should expect three
  56  *   parameters: keyname, ppkey, and location. It should allocate an
  57  *   implementation-specific amount of memory and assign the pointer to that
  58  *   allocated memory to *ppkey. The location parameter can be used for
  59  *   debugging, as it contains the compiler-provided __location__ of the
  60  *   call. This function should return 0 upon success, non-zero upon failure.
  61  *
  62  * @param destroy_tls
  63  *   Destroy thread local storage. This function should expect two parameters:
  64  *   ppkey and location. The ppkey parameter points to a variable containing a
  65  *   thread local storage key previously provided by the create_tls
  66  *   function. The location parameter can be used for debugging, as it
  67  *   contains the compiler-provided __location__ of the call.
  68  *
  69  * @param set_tls
  70  *   Set a thread local storage variable's value. This function should expect
  71  *   three parameters: pkey, pval, and location. The pkey parameter is a
  72  *   thread local storage key previously provided by the create_tls
  73  *   function. The (void *) pval parameter contains the value to be placed in
  74  *   the thread local storage variable identified by pkey. The location
  75  *   parameter can be used for debugging, as it contains the compiler-provided
  76  *   __location__ of the call. This function should return 0 upon success;
  77  *   non-zero otherwise.
  78  *
  79  * @param get_tls
  80  *   Retrieve a thread local storage variable's value. This function should
  81  *   expect two parameters: pkey and location. The pkey parameter is a thread
  82  *   local storage key previously provided by the create_tls function, and
  83  *   which has previously been used in a call to the set_tls function to
  84  *   initialize a thread local storage variable. The location parameter can be
  85  *   used for debugging, as it contains the compiler-provided __location__ of
  86  *   the call. This function should return the (void *) value stored in the
  87  *   variable identified by pkey.
  88  *
  89  * @return {void}
  90  */
  91 void
  92 smbc_thread_impl(
  93         /* Mutex functions. */
  94         int (*create_mutex)(const char *lockname,
  95                             void **pplock,
  96                             const char *location),
  97         void (*destroy_mutex)(void *plock,
  98                               const char *location),
  99         int (*lock_mutex)(void *plock,
 100                           int lock_type,
 101                           const char *location),
 102
 103         /* Thread local storage. */
 104         int (*create_tls)(const char *keyname,
 105                           void **ppkey,
 106                           const char *location),
 107         void (*destroy_tls)(void **ppkey,
 108                             const char *location),
 109         int (*set_tls)(void *pkey,
 110                        const void *pval,
 111                        const char *location),
 112         void *(*get_tls)(void *pkey,
 113                          const char *location)
 114         )
 115 {
 116         static struct smb_thread_functions tf;
 117
 118         tf.create_mutex  = create_mutex;
 119         tf.destroy_mutex = destroy_mutex;
 120         tf.lock_mutex    = lock_mutex;
 121         tf.create_tls    = create_tls;
 122         tf.destroy_tls   = destroy_tls;
 123         tf.set_tls       = set_tls;
 124         tf.get_tls       = get_tls;
 125
 126         smb_thread_set_functions(&tf);
 127 }