contrib/ipfilter/lib/rwlock_emul.c

   1 /*      $FreeBSD$       */
   2
   3 /*
   4  * Copyright (C) 2012 by Darren Reed.
   5  *
   6  * See the IPFILTER.LICENCE file for details on licencing.
   7  *
   8  * $Id$
   9  */
  10
  11 #include "ipf.h"
  12
  13 #define EMM_MAGIC       0x97dd8b3a
  14
  15 void eMrwlock_read_enter(rw, file, line)
  16         eMrwlock_t *rw;
  17         char *file;
  18         int line;
  19 {
  20         if (rw->eMrw_magic != EMM_MAGIC) {
  21                 fprintf(stderr, "%s:eMrwlock_read_enter(%p): bad magic: %#x\n",
  22                         rw->eMrw_owner, rw, rw->eMrw_magic);
  23                 abort();
  24         }
  25         if (rw->eMrw_read != 0 || rw->eMrw_write != 0) {
  26                 fprintf(stderr,
  27                         "%s:eMrwlock_read_enter(%p): already locked: %d/%d\n",
  28                         rw->eMrw_owner, rw, rw->eMrw_read, rw->eMrw_write);
  29                 abort();
  30         }
  31         rw->eMrw_read++;
  32         rw->eMrw_heldin = file;
  33         rw->eMrw_heldat = line;
  34 }
  35
  36
  37 void eMrwlock_write_enter(rw, file, line)
  38         eMrwlock_t *rw;
  39         char *file;
  40         int line;
  41 {
  42         if (rw->eMrw_magic != EMM_MAGIC) {
  43                 fprintf(stderr, "%s:eMrwlock_write_enter(%p): bad magic: %#x\n",
  44                         rw->eMrw_owner, rw, rw->eMrw_magic);
  45                 abort();
  46         }
  47         if (rw->eMrw_read != 0 || rw->eMrw_write != 0) {
  48                 fprintf(stderr,
  49                         "%s:eMrwlock_write_enter(%p): already locked: %d/%d\n",
  50                         rw->eMrw_owner, rw, rw->eMrw_read, rw->eMrw_write);
  51                 abort();
  52         }
  53         rw->eMrw_write++;
  54         rw->eMrw_heldin = file;
  55         rw->eMrw_heldat = line;
  56 }
  57
  58
  59 void eMrwlock_try_upgrade(rw, file, line)
  60         eMrwlock_t *rw;
  61         char *file;
  62         int line;
  63 {
  64         if (rw->eMrw_magic != EMM_MAGIC) {
  65                 fprintf(stderr, "%s:eMrwlock_write_enter(%p): bad magic: %#x\n",
  66                         rw->eMrw_owner, rw, rw->eMrw_magic);
  67                 abort();
  68         }
  69         if (rw->eMrw_read != 0 || rw->eMrw_write != 0) {
  70                 fprintf(stderr,
  71                         "%s:eMrwlock_try_upgrade(%p): already locked: %d/%d\n",
  72                         rw->eMrw_owner, rw, rw->eMrw_read, rw->eMrw_write);
  73                 abort();
  74         }
  75         rw->eMrw_write++;
  76         rw->eMrw_heldin = file;
  77         rw->eMrw_heldat = line;
  78 }
  79
  80 void eMrwlock_downgrade(rw, file, line)
  81         eMrwlock_t *rw;
  82         char *file;
  83         int line;
  84 {
  85         if (rw->eMrw_magic != EMM_MAGIC) {
  86                 fprintf(stderr, "%s:eMrwlock_write_enter(%p): bad magic: %#x\n",
  87                         rw->eMrw_owner, rw, rw->eMrw_magic);
  88                 abort();
  89         }
  90         if (rw->eMrw_read != 0 || rw->eMrw_write != 1) {
  91                 fprintf(stderr,
  92                         "%s:eMrwlock_write_enter(%p): already locked: %d/%d\n",
  93                         rw->eMrw_owner, rw, rw->eMrw_read, rw->eMrw_write);
  94                 abort();
  95         }
  96         rw->eMrw_write--;
  97         rw->eMrw_read++;
  98         rw->eMrw_heldin = file;
  99         rw->eMrw_heldat = line;
 100 }
 101
 102
 103 void eMrwlock_exit(rw)
 104         eMrwlock_t *rw;
 105 {
 106         if (rw->eMrw_magic != EMM_MAGIC) {
 107                 fprintf(stderr, "%s:eMrwlock_exit(%p): bad magic: %#x\n",
 108                         rw->eMrw_owner, rw, rw->eMrw_magic);
 109                 abort();
 110         }
 111         if (rw->eMrw_read != 1 && rw->eMrw_write != 1) {
 112                 fprintf(stderr, "%s:eMrwlock_exit(%p): not locked: %d/%d\n",
 113                         rw->eMrw_owner, rw, rw->eMrw_read, rw->eMrw_write);
 114                 abort();
 115         }
 116         if (rw->eMrw_read == 1)
 117                 rw->eMrw_read--;
 118         else if (rw->eMrw_write == 1)
 119                 rw->eMrw_write--;
 120         rw->eMrw_heldin = NULL;
 121         rw->eMrw_heldat = 0;
 122 }
 123
 124
 125 static int initcount = 0;
 126
 127 void eMrwlock_init(rw, who)
 128         eMrwlock_t *rw;
 129         char *who;
 130 {
 131         if (rw->eMrw_magic == EMM_MAGIC) {      /* safe bet ? */
 132                 fprintf(stderr,
 133                         "%s:eMrwlock_init(%p): already initialised?: %#x\n",
 134                         rw->eMrw_owner, rw, rw->eMrw_magic);
 135                 abort();
 136         }
 137         rw->eMrw_magic = EMM_MAGIC;
 138         rw->eMrw_read = 0;
 139         rw->eMrw_write = 0;
 140         if (who != NULL)
 141                 rw->eMrw_owner = strdup(who);
 142         else
 143                 rw->eMrw_owner = NULL;
 144         initcount++;
 145 }
 146
 147
 148 void eMrwlock_destroy(rw)
 149         eMrwlock_t *rw;
 150 {
 151         if (rw->eMrw_magic != EMM_MAGIC) {
 152                 fprintf(stderr, "%s:eMrwlock_destroy(%p): bad magic: %#x\n",
 153                         rw->eMrw_owner, rw, rw->eMrw_magic);
 154                 abort();
 155         }
 156         if (rw->eMrw_owner != NULL)
 157                 free(rw->eMrw_owner);
 158         memset(rw, 0xa5, sizeof(*rw));
 159         initcount--;
 160 }
 161
 162 void ipf_rwlock_clean()
 163 {
 164         if (initcount != 0)
 165                 abort();
 166 }