Security/libsecurity_asn1/lib/nsprPortX.c

   1 /*
   2  * Copyright (c) 2003-2006,2008,2010-2012 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  *
  23  * nsprPortX.c - minimal platform dependent NSPR functions to enable
  24  *               use of DER libraries
  25  */
  26
  27 #ifndef _NSPR_PORT_X_H_
  28 #define _NSPR_PORT_X_H_
  29
  30 #include "prmem.h"
  31 #include "prlock.h"
  32 #include "prerror.h"
  33 #include "prinit.h"
  34 #include "prbit.h"
  35
  36 #include <stdlib.h>
  37 #include <pthread.h>
  38 #include <string.h>
  39
  40 // MARK: *** Memory ***
  41
  42 NSPR_API(void *) PR_Malloc(PRSize size)
  43 {
  44         return malloc(size ? size : 1);
  45 }
  46 NSPR_API(void *) PR_Calloc(PRSize nelem, PRSize elsize)
  47 {
  48         return calloc(nelem, elsize);
  49 }
  50 NSPR_API(void *) PR_Realloc(void *ptr, PRSize size)
  51 {
  52         return realloc(ptr, size);
  53 }
  54 NSPR_API(void) PR_Free(void *ptr)
  55 {
  56         return free(ptr);
  57 }
  58
  59 // MARK: *** locks ***
  60
  61 NSPR_API(PRLock*) PR_NewLock(void)
  62 {
  63         pthread_mutex_t *pm = PR_Malloc(sizeof(pthread_mutex_t));
  64         if(pm == NULL) {
  65                 return NULL;
  66         }
  67         if(pthread_mutex_init(pm, NULL)) {
  68                 PR_Free(pm);
  69                 return NULL;
  70         }
  71         return (PRLock*)pm;
  72 }
  73
  74 NSPR_API(void) PR_DestroyLock(PRLock *lock)
  75 {
  76         if(lock == NULL) {
  77                 return;
  78         }
  79         pthread_mutex_destroy((pthread_mutex_t *)lock);
  80         PR_Free(lock);
  81 }
  82
  83 NSPR_API(void) PR_Lock(PRLock *lock)
  84 {
  85         if(lock == NULL) {
  86                 return;
  87         }
  88         pthread_mutex_lock((pthread_mutex_t *)lock);
  89 }
  90
  91 NSPR_API(PRStatus) PR_Unlock(PRLock *lock)
  92 {
  93         if(lock == NULL) {
  94                 return PR_FAILURE;
  95         }
  96         pthread_mutex_unlock((pthread_mutex_t *)lock);
  97         return PR_SUCCESS;
  98 }
  99
 100 // MARK: *** get/set error ***
 101
 102 /*
 103  * key for pthread_{set,get}specific and a lock to ensure it gets
 104  * created once
 105  */
 106 static pthread_key_t PR_threadKey;
 107 static int PR_threadKeyInitFlag;                // we have a PR_threadKey
 108 static int PR_threadKeyErrorFlag;               // unable to create PR_threadKey
 109 static pthread_mutex_t PR_threadKeyLock = PTHREAD_MUTEX_INITIALIZER;
 110
 111 /*
 112  * The thing that gets stored on a per-thread basis. A pointer to
 113  * this is associated with key PR_threadKey. Mallocd in
 114  * PR_getThreadErrInfo(); freed directly by free() as
 115  * PR_threadKey's destructor.
 116  */
 117 typedef struct {
 118         PRInt32                 osError;
 119         PRErrorCode     prError;
 120 } PR_threadErrInfo;
 121
 122 /*
 123  * One-time init of PR_threadKey, returns nonzero on error.
 124  * Does not attempt to init PR_threadKey if doCreate is false and
 125  * a previous call to this routine resulted in error (i.e., this
 126  * is the GetXError() following a failed SetError()).
 127  */
 128 static PRInt32 PR_initThreadKey(
 129         int doCreate)
 130 {
 131         PRInt32 prtn = 0;
 132         if(PR_threadKeyInitFlag) {
 133                 /* thread safe since we never clear this flag; we're ready to go */
 134                 return 0;
 135         }
 136         pthread_mutex_lock(&PR_threadKeyLock);
 137         if(PR_threadKeyErrorFlag && !doCreate) {
 138                 /* no error to get because the last SetXError failed */
 139                 prtn = PR_IO_ERROR;
 140         }
 141         else if(!PR_threadKeyInitFlag) {
 142                 prtn = pthread_key_create(&PR_threadKey, free);
 143                 if(prtn) {
 144                         /* out of pthread_key_t's */
 145                         PR_threadKeyErrorFlag = 1;
 146                 }
 147                 else {
 148                         PR_threadKeyErrorFlag = 0;      // in case of retry */
 149                         PR_threadKeyInitFlag = 1;       // success
 150                 }
 151         }
 152         pthread_mutex_unlock(&PR_threadKeyLock);
 153         return prtn;
 154 }
 155
 156 /*
 157  * Get current thread's PR_threadErrInfo. Create one if doCreate is
 158  * true and one does not exist.
 159  *
 160  * -- A nonzero *threadKeyError on return indicates that we can
 161  *    not create a pthread_key_t; in this case we return NULL.
 162  * -- Note that NULL return with zero threadKeyError and zero
 163  *    doCreate indicates "no per-thread error set yet", which is
 164  *    not an error.
 165  */
 166 static PR_threadErrInfo *PR_getThreadErrInfo(
 167         int doCreate,
 168         PRInt32 *threadKeyError)                // RETURNED, an OSStatus
 169 {
 170         *threadKeyError = PR_initThreadKey(doCreate);
 171         if(*threadKeyError) {
 172                 return NULL;
 173         }
 174         PR_threadErrInfo *errInfo = pthread_getspecific(PR_threadKey);
 175         if((errInfo == NULL) && doCreate) {
 176                 errInfo = (PR_threadErrInfo *)malloc(sizeof(*errInfo));
 177                 if(errInfo == NULL) {
 178                         /*
 179                          * malloc failure, retriable failure of this routine (not
 180                          * a PR_threadKeyErrorFlag style error).
 181                          * Note that this is *not* detected in a subsequent
 182                          * GetXError() call, but it will allow for somewhat
 183                          * graceful recovery in case some memory gets freed
 184                          * up.
 185                          */
 186                         *threadKeyError = PR_OUT_OF_MEMORY_ERROR;
 187                 }
 188                 else {
 189                         memset(errInfo, 0, sizeof(*errInfo));
 190                         pthread_setspecific(PR_threadKey, errInfo);
 191                 }
 192         }
 193         return errInfo;
 194 }
 195
 196 PR_IMPLEMENT(PRErrorCode) PR_GetError(void)
 197 {
 198         PRInt32 prtn;
 199         PR_threadErrInfo *errInfo = PR_getThreadErrInfo(0, &prtn);
 200         if(errInfo == NULL) {
 201                 /* no error set or per-thread logic uninitialized */
 202                 if(prtn) {
 203                         return PR_INSUFFICIENT_RESOURCES_ERROR;
 204                 }
 205                 else {
 206                         return 0;
 207                 }
 208         }
 209         else {
 210                 return errInfo->prError;
 211         }
 212 }
 213
 214 PR_IMPLEMENT(PRInt32) PR_GetOSError(void)
 215 {
 216         PRInt32 prtn;
 217         PR_threadErrInfo *errInfo = PR_getThreadErrInfo(0, &prtn);
 218         if(errInfo == NULL) {
 219                 /* no error set or per-thread logic uninitialized */
 220                 return prtn;
 221         }
 222         else {
 223                 return errInfo->osError;
 224         }
 225 }
 226
 227 PR_IMPLEMENT(void) PR_SetError(PRErrorCode code, PRInt32 osErr)
 228 {
 229         PRInt32 prtn;
 230         PR_threadErrInfo *errInfo = PR_getThreadErrInfo(1, &prtn);
 231         if(errInfo != NULL) {
 232                 errInfo->osError = osErr;
 233                 errInfo->prError = code;
 234         }
 235         /* else per-thread logic uninitialized */
 236 }
 237
 238 // MARK: *** misc. ***
 239
 240 /*
 241 ** Compute the log of the least power of 2 greater than or equal to n
 242 */
 243 NSPR_API(PRIntn) PR_CeilingLog2(PRUint32 i)
 244 {
 245         PRIntn r;
 246         PR_CEILING_LOG2(r,i);
 247         return r;
 248 }
 249
 250 #endif  /* _NSPR_PORT_X_H_ */