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rwlock_emul.c revision 1.1 
      1 /*	$NetBSD: rwlock_emul.c,v 1.1 2012/03/23 21:20:10 christos Exp $	*/
      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_downgrade(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 != 1) {
     70 		fprintf(stderr,
     71 			"%s:eMrwlock_write_enter(%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_read++;
     77 	rw->eMrw_heldin = file;
     78 	rw->eMrw_heldat = line;
     79 }
     80 
     81 
     82 void eMrwlock_exit(rw)
     83 	eMrwlock_t *rw;
     84 {
     85 	if (rw->eMrw_magic != EMM_MAGIC) {
     86 		fprintf(stderr, "%s:eMrwlock_exit(%p): bad magic: %#x\n",
     87 			rw->eMrw_owner, rw, rw->eMrw_magic);
     88 		abort();
     89 	}
     90 	if (rw->eMrw_read != 1 && rw->eMrw_write != 1) {
     91 		fprintf(stderr, "%s:eMrwlock_exit(%p): not locked: %d/%d\n",
     92 			rw->eMrw_owner, rw, rw->eMrw_read, rw->eMrw_write);
     93 		abort();
     94 	}
     95 	if (rw->eMrw_read == 1)
     96 		rw->eMrw_read--;
     97 	else if (rw->eMrw_write == 1)
     98 		rw->eMrw_write--;
     99 	rw->eMrw_heldin = NULL;
    100 	rw->eMrw_heldat = 0;
    101 }
    102 
    103 
    104 static int initcount = 0;
    105 
    106 void eMrwlock_init(rw, who)
    107 	eMrwlock_t *rw;
    108 	char *who;
    109 {
    110 	if (rw->eMrw_magic == EMM_MAGIC) {	/* safe bet ? */
    111 		fprintf(stderr,
    112 			"%s:eMrwlock_init(%p): already initialised?: %#x\n",
    113 			rw->eMrw_owner, rw, rw->eMrw_magic);
    114 		abort();
    115 	}
    116 	rw->eMrw_magic = EMM_MAGIC;
    117 	rw->eMrw_read = 0;
    118 	rw->eMrw_write = 0;
    119 	if (who != NULL)
    120 		rw->eMrw_owner = strdup(who);
    121 	else
    122 		rw->eMrw_owner = NULL;
    123 	initcount++;
    124 }
    125 
    126 
    127 void eMrwlock_destroy(rw)
    128 	eMrwlock_t *rw;
    129 {
    130 	if (rw->eMrw_magic != EMM_MAGIC) {
    131 		fprintf(stderr, "%s:eMrwlock_destroy(%p): bad magic: %#x\n",
    132 			rw->eMrw_owner, rw, rw->eMrw_magic);
    133 		abort();
    134 	}
    135 	if (rw->eMrw_owner != NULL)
    136 		free(rw->eMrw_owner);
    137 	memset(rw, 0xa5, sizeof(*rw));
    138 	initcount--;
    139 }
    140 
    141 void ipf_rwlock_clean()
    142 {
    143 	if (initcount != 0)
    144 		abort();
    145 }
    146