BSD 4 development

[unix-history] / usr / src / cmd / uucp / uurecover.c

#include <stdio.h>
#include <a.out.h>
#include <param.h>
#include <proc.h>
#include <sys/stat.h>
struct stat xstat;
struct proc mproc[NPROC];
struct nlist nl[]
{       { "_proc"},
       { ""},
};
int err;
main(argc,argv) char **argv;
{       int i,j;
       if(argc<=1) exit(0);
       for(i=1;i<argc;i++)
       {       if((j=isalock(argv[i]))>0)
                       if(isapid(j))
                       {       fprintf(stderr,"recovery: %s in use\n",argv[i]);
                               err=1;
                       }
                       else    unlink(argv[i]);
               else    fprintf(stderr,"reocvery: %s not a lock\n",argv[i]);
       }
       exit(err);
}
isalock(s) char *s;
{       int pid,fd;
       if(stat(s,&xstat)<0) return(0);
       if(xstat.st_size!=2) return(0);
       fd=open(s,0);
       if(fd<0) return(-1);
       read(fd,&pid,2);
       close(fd);
       return(pid);
}
int gotpids,pids[NPROC];
isapid(n)
{       int i;
       if(gotpids==0) getpids();
       for(i=0;i<NPROC;i++)
               if(n==pids[i]) return(1);
       return(0);
}
getpids()
{       int i,mem;
       nlist("/unix",nl);
       if(nl[0].n_type==0)
       {       fprintf(stderr,"no namelist, no lock recovery\n");
               exit(1);
       }
       mem=open("/dev/mem",0);
       lseek(mem,(long)nl[0].n_value,0);
       read(mem,mproc,sizeof(mproc));
       if(mproc[0].p_pid != 0)
       {       fprintf(stderr,"/unix not loaded, no lock recovery\n");
               exit(1);
       }
       for(i=0;i<NPROC;i++)
       {       if(mproc[i].p_stat==0 ||
                       mproc[i].p_stat==SZOMB)
                       pids[i]=0;
               else    pids[i]=mproc[i].p_pid;
       }
       gotpids=1;
}
unlock(s) char *s;
{
       unlink(s);
}