source/lib/data_blob.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Easy management of byte-length data
   4    Copyright (C) Andrew Tridgell 2001
   5    Copyright (C) Andrew Bartlett 2001
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 /*******************************************************************
  25  Free() a data blob.
  26 *******************************************************************/
  27
  28 static void free_data_blob(DATA_BLOB *d)
  29 {
  30         if ((d) && (d->free)) {
  31                 SAFE_FREE(d->data);
  32         }
  33 }
  34
  35 /*******************************************************************
  36  Construct a data blob, must be freed with data_blob_free().
  37  You can pass NULL for p and get a blank data blob
  38 *******************************************************************/
  39
  40 DATA_BLOB data_blob(const void *p, size_t length)
  41 {
  42         DATA_BLOB ret;
  43
  44         if (!length) {
  45                 ZERO_STRUCT(ret);
  46                 return ret;
  47         }
  48
  49         if (p) {
  50                 ret.data = (uint8 *)smb_xmemdup(p, length);
  51         } else {
  52                 ret.data = SMB_XMALLOC_ARRAY(uint8, length);
  53         }
  54         ret.length = length;
  55         ret.free = free_data_blob;
  56         return ret;
  57 }
  58
  59 /*******************************************************************
  60  Construct a data blob, using supplied TALLOC_CTX.
  61 *******************************************************************/
  62
  63 DATA_BLOB data_blob_talloc(TALLOC_CTX *mem_ctx, const void *p, size_t length)
  64 {
  65         DATA_BLOB ret;
  66
  67         if (!length) {
  68                 ZERO_STRUCT(ret);
  69                 return ret;
  70         }
  71
  72         if (p) {
  73                 ret.data = (uint8 *)TALLOC_MEMDUP(mem_ctx, p, length);
  74                 if (ret.data == NULL)
  75                         smb_panic("data_blob_talloc: TALLOC_MEMDUP failed.\n");
  76         } else {
  77                 ret.data = (uint8 *)TALLOC(mem_ctx, length);
  78                 if (ret.data == NULL)
  79                         smb_panic("data_blob_talloc: talloc failed.\n");
  80         }
  81
  82         ret.length = length;
  83         ret.free = NULL;
  84         return ret;
  85 }
  86
  87 /*******************************************************************
  88  Free a data blob.
  89 *******************************************************************/
  90
  91 void data_blob_free(DATA_BLOB *d)
  92 {
  93         if (d) {
  94                 if (d->free) {
  95                         (d->free)(d);
  96                 }
  97                 d->length = 0;
  98         }
  99 }
 100
 101 /*******************************************************************
 102  Clear a DATA_BLOB's contents
 103 *******************************************************************/
 104
 105 void data_blob_clear(DATA_BLOB *d)
 106 {
 107         if (d->data) {
 108                 memset(d->data, 0, d->length);
 109         }
 110 }
 111
 112 /*******************************************************************
 113  Free a data blob and clear its contents
 114 *******************************************************************/
 115
 116 void data_blob_clear_free(DATA_BLOB *d)
 117 {
 118         data_blob_clear(d);
 119         data_blob_free(d);
 120 }
 121
 122 /**
 123   useful for constructing data blobs in test suites, while
 124   avoiding const warnings
 125 **/
 126 DATA_BLOB data_blob_string_const(const char *str)
 127 {
 128         DATA_BLOB blob;
 129         blob.data = CONST_DISCARD(uint8 *, str);
 130         blob.length = strlen(str);
 131         blob.free = NULL;
 132         return blob;
 133 }
 134
 135 /**
 136  * Create a new data blob from const data
 137  */
 138 DATA_BLOB data_blob_const(const void *p, size_t length)
 139 {
 140         DATA_BLOB blob;
 141         blob.data = CONST_DISCARD(uint8 *, p);
 142         blob.length = length;
 143         blob.free = NULL;
 144         return blob;
 145 }