lib/libc/include/nscache.h

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2005 Michael Bushkov <bushman@rsu.ru>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  * $FreeBSD$
  29  */
  30
  31 #ifndef __NS_CACHE_H__
  32 #define __NS_CACHE_H__
  33
  34 #include "nscachedcli.h"
  35
  36 typedef int (*nss_cache_id_func_t)(char *, size_t *, va_list, void *);
  37 typedef int (*nss_cache_marshal_func_t)(char *, size_t *, void *, va_list,
  38         void *);
  39 typedef int (*nss_cache_unmarshal_func_t)(char *, size_t, void *, va_list,
  40         void *);
  41
  42 typedef void (*nss_set_mp_ws_func_t)(cached_mp_write_session);
  43 typedef cached_mp_write_session (*nss_get_mp_ws_func_t)(void);
  44
  45 typedef void (*nss_set_mp_rs_func_t)(cached_mp_read_session);
  46 typedef cached_mp_read_session  (*nss_get_mp_rs_func_t)(void);
  47
  48 typedef struct _nss_cache_info {
  49         char    *entry_name;
  50         void    *mdata;
  51
  52         /*
  53          * These 3 functions should be implemented specifically for each
  54          * nsswitch database.
  55          */
  56         nss_cache_id_func_t id_func;    /* marshals the request parameters */
  57         nss_cache_marshal_func_t marshal_func;     /* marshals response */
  58         nss_cache_unmarshal_func_t unmarshal_func; /* unmarshals response */
  59
  60         /*
  61          * These 4 functions should be generated with NSS_MP_CACHE_HANDLING
  62          * macro.
  63          */
  64         nss_set_mp_ws_func_t set_mp_ws_func; /* sets current write session */
  65         nss_get_mp_ws_func_t get_mp_ws_func; /* gets current write session */
  66
  67         nss_set_mp_rs_func_t set_mp_rs_func; /* sets current read session */
  68         nss_get_mp_rs_func_t get_mp_rs_func; /* gets current read session */
  69 } nss_cache_info;
  70
  71 /*
  72  * NSS_MP_CACHE_HANDLING implements the set_mp_ws, get_mp_ws, set_mp_rs,
  73  * get_mp_rs functions, that are used in _nss_cache_info. It uses
  74  * NSS_TLS_HANDLING macro to organize thread local storage.
  75  */
  76 #define NSS_MP_CACHE_HANDLING(name)                                     \
  77 struct name##_mp_state {                                                \
  78         cached_mp_write_session mp_write_session;                       \
  79         cached_mp_read_session  mp_read_session;                        \
  80 };                                                                      \
  81                                                                         \
  82 static void                                                             \
  83 name##_mp_endstate(void *s) {                                           \
  84         struct name##_mp_state  *mp_state;                              \
  85                                                                         \
  86         mp_state = (struct name##_mp_state *)s;                         \
  87         if (mp_state->mp_write_session != INVALID_CACHED_MP_WRITE_SESSION)\
  88                 __abandon_cached_mp_write_session(mp_state->mp_write_session);\
  89                                                                         \
  90         if (mp_state->mp_read_session != INVALID_CACHED_MP_READ_SESSION)\
  91                 __close_cached_mp_read_session(mp_state->mp_read_session);\
  92 }                                                                       \
  93 NSS_TLS_HANDLING(name##_mp);                                            \
  94                                                                         \
  95 static void                                                             \
  96 name##_set_mp_ws(cached_mp_write_session ws)                            \
  97 {                                                                       \
  98         struct name##_mp_state  *mp_state;                              \
  99         int     res;                                                    \
 100                                                                         \
 101         res = name##_mp_getstate(&mp_state);                            \
 102         if (res != 0)                                                   \
 103                 return;                                                 \
 104                                                                         \
 105         mp_state->mp_write_session = ws;                                \
 106 }                                                                       \
 107                                                                         \
 108 static cached_mp_write_session                                          \
 109 name##_get_mp_ws(void)                                                  \
 110 {                                                                       \
 111         struct name##_mp_state  *mp_state;                              \
 112         int     res;                                                    \
 113                                                                         \
 114         res = name##_mp_getstate(&mp_state);                            \
 115         if (res != 0)                                                   \
 116                 return (INVALID_CACHED_MP_WRITE_SESSION);               \
 117                                                                         \
 118         return (mp_state->mp_write_session);                            \
 119 }                                                                       \
 120                                                                         \
 121 static void                                                             \
 122 name##_set_mp_rs(cached_mp_read_session rs)                             \
 123 {                                                                       \
 124         struct name##_mp_state  *mp_state;                              \
 125         int     res;                                                    \
 126                                                                         \
 127         res = name##_mp_getstate(&mp_state);                            \
 128         if (res != 0)                                                   \
 129                 return;                                                 \
 130                                                                         \
 131         mp_state->mp_read_session = rs;                                 \
 132 }                                                                       \
 133                                                                         \
 134 static cached_mp_read_session                                           \
 135 name##_get_mp_rs(void)                                                  \
 136 {                                                                       \
 137         struct name##_mp_state  *mp_state;                              \
 138         int     res;                                                    \
 139                                                                         \
 140         res = name##_mp_getstate(&mp_state);                            \
 141         if (res != 0)                                                   \
 142                 return (INVALID_CACHED_MP_READ_SESSION);                \
 143                                                                         \
 144         return (mp_state->mp_read_session);                             \
 145 }
 146
 147 /*
 148  * These macros should be used to initialize _nss_cache_info structure. For
 149  * multipart queries in setXXXent and getXXXent functions mf and uf
 150  * (marshal function and unmarshal function) should be both NULL.
 151  */
 152 #define NS_COMMON_CACHE_INFO_INITIALIZER(name, mdata, if, mf, uf)       \
 153         {#name, mdata, if, mf, uf, NULL, NULL, NULL, NULL}
 154 #define NS_MP_CACHE_INFO_INITIALIZER(name, mdata, mf, uf)               \
 155         {#name, mdata, NULL, mf, uf, name##_set_mp_ws, name##_get_mp_ws,\
 156                 name##_set_mp_rs, name##_get_mp_rs }
 157
 158 /*
 159  * Analog of other XXX_CB macros. Has the pointer to _nss_cache_info
 160  * structure as the only argument.
 161  */
 162 #define NS_CACHE_CB(cinfo) {NSSRC_CACHE, __nss_cache_handler, (void *)(cinfo) },
 163
 164 /* args are: current pointer, current buffer, initial buffer, pointer type */
 165 #define NS_APPLY_OFFSET(cp, cb, ib, p_type)                             \
 166         if ((cp) != NULL)                                               \
 167                 (cp) = (p_type)((char *)(cb) + (size_t)(cp) - (size_t)(ib))
 168 /*
 169  * Gets new pointer from the marshalled buffer by uisng initial address
 170  * and initial buffer address
 171  */
 172 #define NS_GET_NEWP(cp, cb, ib)                                         \
 173         ((char *)(cb) + (size_t)(cp) - (size_t)(ib))
 174
 175 typedef struct _nss_cache_data {
 176         char    *key;
 177         size_t  key_size;
 178
 179         nss_cache_info const    *info;
 180 } nss_cache_data;
 181
 182 __BEGIN_DECLS
 183 /* dummy function, which is needed to make nss_method_lookup happy */
 184 extern  int     __nss_cache_handler(void *, void *, va_list);
 185
 186 #ifdef _NS_PRIVATE
 187 extern  int     __nss_common_cache_read(void *, void *, va_list);
 188 extern  int     __nss_common_cache_write(void *, void *, va_list);
 189 extern  int     __nss_common_cache_write_negative(void *);
 190
 191 extern  int     __nss_mp_cache_read(void *, void *, va_list);
 192 extern  int     __nss_mp_cache_write(void *, void *, va_list);
 193 extern  int     __nss_mp_cache_write_submit(void *, void *, va_list);
 194 extern  int     __nss_mp_cache_end(void *, void *, va_list);
 195 #endif /* _NS_PRIVATE */
 196
 197 __END_DECLS
 198
 199 #endif