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#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <errno.h>
#include <sys/stat.h>
#include "xutil.h"
#include "lutil.h"
#include "ftn.h"
#ifdef NEED_BSY
#if defined(SHORT_PID_T)
#define pid_t short
#elif defined(INT_PID_T)
#define pid_t int
#endif
extern char *bsyname(faddr *);
extern void mkdirs(char*);
int nodelock(addr)
faddr *addr;
{
char *fn,*tfn,*p;
char tmp[16];
FILE *fp;
pid_t pid,mypid;
int tmppid,sverr;
debug(4,"try locking node %s",ascfnode(addr,0x1f));
fn=bsyname(addr);
tfn=xstrcpy(fn);
if ((p=strrchr(tfn,'/'))) *++p='\0';
mypid=getpid();
sprintf(tmp,"aa%d",mypid);
tfn=xstrcat(tfn,tmp);
mkdirs(tfn);
if ((fp=fopen(tfn,"w")) == NULL) {
logerr("$cannot open tmp file for bsy lock \"%s\"",tfn);
free(tfn);
return 1;
}
fprintf(fp,"%10d\n",mypid);
fclose(fp);
chmod(tfn,0444);
if (link(tfn,fn) == 0) {
debug(4,"created lock OK");
unlink(tfn);
free(tfn);
return 0;
} else {
sverr=errno;
debug(4,".bsy file present, check staleness");
}
if (sverr != EEXIST) {
logerr("$could not link \"%s\" to \"%s\"",tfn,fn);
unlink(tfn);
free(tfn);
return 1;
}
if ((fp=fopen(fn,"r")) == NULL) {
logerr("$could not open existing lock file \"%s\"",fn);
unlink(tfn);
free(tfn);
return 1;
}
fscanf(fp,"%d",&tmppid);
pid=tmppid;
fclose(fp);
debug(4,"opened bsy file for pid %d",pid);
if (kill(pid,0) && (errno == ESRCH)) {
loginf("found stale bsy file for %s, unlink",
ascfnode(addr,0x1f));
unlink(fn);
} else {
debug(4,"process active, lock failed");
unlink(tfn);
free(tfn);
return 1;
}
if (link(tfn,fn) == 0) {
debug(4,"created lock OK");
unlink(tfn);
free(tfn);
return 0;
} else {
logerr("$could not link \"%s\" to \"%s\"",tfn,fn);
unlink(tfn);
free(tfn);
return 1;
}
}
int nodeulock(addr)
faddr *addr;
{
char *fn;
FILE *fp;
pid_t pid,mypid;
int tmppid;
debug(4,"try unlocking node %s",ascfnode(addr,0x1f));
fn=bsyname(addr);
if ((fp=fopen(fn,"r")) == NULL) {
logerr("$cannot open lock file \"%s\"",fn);
return 1;
}
fscanf(fp,"%d",&tmppid);
pid=tmppid;
fclose(fp);
mypid=getpid();
if (pid == mypid) {
debug(4,"unlinking lock file");
unlink(fn);
return 0;
} else {
logerr("trying unlock file for process %u, we are %u",
pid,mypid);
return 1;
}
}
#else /* don't NEED_BSY */
int nodelock(addr)
faddr *addr;
{
debug(4,"try locking node %s - no locking",ascfnode(addr,0x1f));
return 0;
}
int nodeulock(addr)
faddr *addr;
{
debug(4,"try unlocking node %s - no locking",ascfnode(addr,0x1f));
return 0;
}
#endif /* NEED_BSY */
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