xref: /illumos-gate/usr/src/lib/krb5/dyn/dyn_delete.c (revision 48bbca81)
1 #pragma ident	"%Z%%M%	%I%	%E% SMI"
2 
3 /*
4  * This file is part of libdyn.a, the C Dynamic Object library.  It
5  * contains the source code for the function DynDelete().
6  *
7  * There are no restrictions on this code; however, if you make any
8  * changes, I request that you document them so that I do not get
9  * credit or blame for your modifications.
10  *
11  * Written by Barr3y Jaspan, Student Information Processing Board (SIPB)
12  * and MIT-Project Athena, 1989.
13  * Copyright (c) 2016 by Delphix. All rights reserved.
14  */
15 
16 #include <stdio.h>
17 #include <strings.h>
18 #include <string.h>
19 
20 #include "dynP.h"
21 
22 /*
23  * Checkers!  Get away from that "hard disk erase" button!
24  *    (Stupid dog.  He almost did it to me again ...)
25  */
DynDelete(obj,idx)26 int DynDelete(obj, idx)
27    DynObjectP obj;
28    int idx;
29 {
30      if (idx < 0) {
31 	  if (obj->debug)
32 	       fprintf(stderr, "dyn: delete: bad index %d\n", idx);
33 	  return DYN_BADINDEX;
34      }
35 
36      if (idx >= obj->num_el) {
37 	  if (obj->debug)
38 	       fprintf(stderr, "dyn: delete: Highest index is %d.\n",
39 		       obj->num_el);
40 	  return DYN_BADINDEX;
41      }
42 
43      if (idx == obj->num_el-1) {
44 	  if (obj->paranoid) {
45 	       if (obj->debug)
46 		    fprintf(stderr, "dyn: delete: last element, zeroing.\n");
47 	       memset(obj->array + idx*obj->el_size, 0, obj->el_size);
48 	  }
49 	  else {
50 	       if (obj->debug)
51 		    fprintf(stderr, "dyn: delete: last element, punting.\n");
52 	  }
53      }
54      else {
55 	  if (obj->debug)
56 	       fprintf(stderr,
57 		       "dyn: delete: copying %d bytes from %d + %d to + %d.\n",
58 		       obj->el_size*(obj->num_el - idx), obj->array,
59 		       (idx+1)*obj->el_size, idx*obj->el_size);
60 
61 #ifdef HAVE_MEMMOVE
62 	  memmove(obj->array + idx*obj->el_size,
63 		  obj->array + (idx+1)*obj->el_size,
64 		  obj->el_size*(obj->num_el - idx));
65 #else
66 	  bcopy(obj->array + (idx+1)*obj->el_size,
67 		  obj->array + idx*obj->el_size,
68 		  obj->el_size*(obj->num_el - idx));
69 #endif
70 	  if (obj->paranoid) {
71 	       if (obj->debug)
72 		    fprintf(stderr,
73 			    "dyn: delete: zeroing %d bytes from %d + %d\n",
74 			    obj->el_size, obj->array,
75 			    obj->el_size*(obj->num_el - 1));
76 	       memset(obj->array + obj->el_size*(obj->num_el - 1), 0,
77 		     obj->el_size);
78 	  }
79      }
80 
81      --obj->num_el;
82 
83      if (obj->debug)
84 	  fprintf(stderr, "dyn: delete: done.\n");
85 
86      return DYN_OK;
87 }
88