SecuritySNACCRuntime/c-lib/inc/str-stk.h

   1 /*
   2  * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * The contents of this file constitute Original Code as defined in and are
   5  * subject to the Apple Public Source License Version 1.2 (the 'License').
   6  * You may not use this file except in compliance with the License. Please obtain
   7  * a copy of the License at http://www.apple.com/publicsource and read it before
   8  * using this file.
   9  *
  10  * This Original Code and all software distributed under the License are
  11  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
  12  * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
  13  * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  14  * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
  15  * specific language governing rights and limitations under the License.
  16  */
  17
  18
  19 /*
  20  * str_stk.h  - maintains a stack of the components of a bit string
  21  * or octet string so they can be copied into a single chunk
  22  *
  23  *
  24  *  CONSTRUCTED BIT AND OCTET STRINGS SUCK. They should be
  25  *  specified in the application's ASN.1 spec as SEQUENCE OF OCTET STRING
  26  *
  27  * this stack stuff is for decoding constructed bit/octet strings
  28  * so the user gets a single contiguous bit/octet str instead of
  29  * irritating little pieces.  This does not cost a lot more than
  30  * a linked octet/bit string type since we're copying from the
  31  * buffer anyway, not referencing it directly (even in simple case).
  32  * It will cost more if the string stk overflows and
  33  * needs to be enlarged via realloc - set the values of
  34  * initialStkSizeG, and stkGrowSize carefully for your application.
  35  * Once the StkSize grows, it doesn't shrink back ever.
  36  *
  37  * Only three routine use/deal with this stack garbage
  38  *  BDecConsAsnOcts
  39  *  BDecConsAsnBits
  40  *  SetupConsBitsOctsStringStk
  41  *
  42  * Copyright (C) 1992 Michael Sample and the University of British Columbia
  43  *
  44  * This library is free software; you can redistribute it and/or
  45  * modify it provided that this copyright/license information is retained
  46  * in original form.
  47  *
  48  * If you modify this file, you must clearly indicate your changes.
  49  *
  50  * This source code is distributed in the hope that it will be
  51  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  52  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  53  *
  54  * $Header: /cvs/Darwin/Security/SecuritySNACCRuntime/c-lib/inc/str-stk.h,v 1.1.1.1 2001/05/18 23:14:08 mb Exp $
  55  * $Log: str-stk.h,v $
  56  * Revision 1.1.1.1  2001/05/18 23:14:08  mb
  57  * Move from private repository to open source repository
  58  *
  59  * Revision 1.2  2001/05/05 00:59:23  rmurphy
  60  * Adding darwin license headers
  61  *
  62  * Revision 1.1.1.1  1999/03/16 18:06:22  aram
  63  * Originals from SMIME Free Library.
  64  *
  65  * Revision 1.2  1995/07/24 21:01:24  rj
  66  * changed `_' to `-' in file names.
  67  *
  68  * Revision 1.1  1994/08/28  09:45:41  rj
  69  * first check-in. for a list of changes to the snacc-1.1 distribution please refer to the ChangeLog.
  70  *
  71  */
  72
  73 typedef struct StrStkElmt
  74 {
  75     char *str;
  76     unsigned long int len;
  77 } StrStkElmt;
  78
  79 typedef struct StrStk
  80 {
  81     StrStkElmt *stk; /* ptr to array of SSElmts with 'size' elmts */
  82     unsigned long int initialNumElmts;
  83     unsigned long int numElmts;  /* total # of elements in str stk */
  84     unsigned long int growElmts; /* # elmts to increase size by when nec */
  85     unsigned long int nextFreeElmt; /* index of next free element */
  86     unsigned long int totalByteLen; /* octet len of string stored in stk */
  87 } StrStk;
  88
  89
  90 extern StrStk strStkG;
  91
  92 /*
  93  * initializes stk (Allocates if nec.)
  94  * once stk is enlarged, it doesn't shrink
  95  */
  96 #define RESET_STR_STK()\
  97 {\
  98     strStkG.nextFreeElmt = 0;\
  99     strStkG.totalByteLen = 0;\
 100     if (strStkG.stk == NULL){\
 101        strStkG.stk = (StrStkElmt*) malloc ((strStkG.initialNumElmts) *sizeof (StrStkElmt));\
 102        strStkG.numElmts = strStkG.initialNumElmts;}\
 103 }
 104
 105
 106 /*
 107  * add a char*,len pair to top of stack.
 108  * grows stack if necessary using realloc (!)
 109  */
 110 #define PUSH_STR(strPtr, strsLen, env)\
 111 {\
 112     if (strStkG.nextFreeElmt >= strStkG.numElmts)\
 113     {\
 114        strStkG.stk = (StrStkElmt*) realloc (strStkG.stk, (strStkG.numElmts + strStkG.growElmts) *sizeof (StrStkElmt));\
 115        strStkG.numElmts += strStkG.growElmts;\
 116     }\
 117     strStkG.totalByteLen += strsLen;\
 118     strStkG.stk[strStkG.nextFreeElmt].str = strPtr;\
 119     strStkG.stk[strStkG.nextFreeElmt].len = strsLen;\
 120     strStkG.nextFreeElmt++;\
 121 }
 122
 123
 124 /*
 125  * Set up size values for the stack that is used for merging constructed
 126  * octet or bit string into single strings.
 127  * ****  Call this before decoding anything. *****
 128  * Note: you don't have to call this if the default values
 129  * for initialStkSizeG and stkGrowSizeG are acceptable
 130  */
 131 #define SetupConsBitsOctsStringStk (initialNumberOfElmts, numberOfElmtsToGrowBy)\
 132 {\
 133     strStkG.initialNumElmts = initialNumberOfElmts; \
 134     strStkG.growElmts = numberOfElmtsToGrowBy;\
 135 }