hunt7.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

#ifndef lint
static char *sccsid = "@(#)hunt7.c	4.1 (Berkeley) 5/6/83";
#endif

#include <stdio.h>
#include <assert.h>
#define SAME 0
#define FGCT 10
#define FGSIZE 150

int keepold = 1;	/* keep old things for fgrep search */
char fgspace[FGSIZE];
char *fgp = fgspace;
char *fgnames[FGCT];
char **fgnamp = fgnames;

findline(in, out, outlen, indexdate)
long indexdate;
char *in, *out;
{
	static char name[100] = "";
	char *p, **ftp;
	extern long gdate();
	static FILE *fa = NULL;
	long lp, llen;
	int len, k, nofil;

# if D1
	fprintf(stderr, "findline: %s\n", in);
# endif
	if (mindex(in, '!'))
		return(remote(in, out));
	nofil = in[0]==0;
	for(p=in; *p && *p != ':' && *p != ';'; p++)
		;
	if (*p) *p++=0;
	else p=in;
	k = sscanf(p, "%ld,%ld", &lp, &llen);
# ifdef D1
	fprintf(stderr, "p %s k %d lp %ld llen %ld\n",p,k,lp,llen);
# endif
	if (k<2)
	{
		lp = 0;
		llen=outlen;
	}
# ifdef D1
	fprintf(stderr, "lp %ld llen %ld\n",lp, llen);
# endif
# ifdef D1
	fprintf(stderr, "fa now %o, p %o in %o %s\n",fa, p,in,in);
# endif
	if (nofil)
	{
# if D1
		fprintf(stderr, "set fa to stdin\n");
# endif
		fa = stdin;
	}
	else
		if (strcmp (name, in) != 0 || 1)
		{
# if D1
			fprintf(stderr, "old: %s new %s not equal\n",name,in);
# endif
			if (fa != NULL)
				fa = freopen(in, "r", fa);
			else
				fa = fopen(in, "r");
# if D1
			if (fa==NULL)
				fprintf(stderr, "failed to (re)open *%s*\n",in);
# endif
			if (fa == NULL)
				return(0);
			/* err("Can't open %s", in); */
			strcpy(name, in);
			if (gdate(fa) > indexdate && indexdate != 0)
			{
				if (keepold)
				{
					for(ftp=fgnames; ftp<fgnamp; ftp++)
						if (strcmp(*ftp, name)==SAME)
							return(0);
					strcpy (*fgnamp++ = fgp, name);
					assert(fgnamp<fgnames+FGCT);
					while (*fgp && *fgp!=':')
						fgp++;
					*fgp++ = 0;
					assert (fgp<fgspace+FGSIZE);
					return(0);
				}
				fprintf(stderr, "Warning: index predates file '%s'\n", name);
			}
		}
# if D1
		else
			fprintf(stderr, "old %s new %s same fa %o\n", name,in,fa);
# endif
	if (fa != NULL)
	{
		fseek (fa, lp, 0);
		len = (llen >= outlen) ? outlen-1 : llen;
		len = fread (out, 1, len, fa);
		out[len] = 0;
# ifdef D1
		fprintf(stderr, "length as read is %d\n",len);
# endif
	}
	return(len);
}