v06i017: context - generalized context printer (context)

[sources-request at mirror.UUCP]

Submitted by: genrad!decvax!cwruecmp!ncoast!allbery (Brandon S. Allbery)
Mod.sources: Volume 6, Issue 17
Archive-name: context

#!/bin/sh
# This is a shell archive.  Remove anything before this line,
# then unpack it by saving it in a file and typing "sh file".
# Contents:  README context.c
 
echo x - README
sed 's/^XX//' > "README" <<'@//E*O*F README//'
XXThe following file is my context'' program for displaying the context of
XXa message of the general form

XX	<garbage> filename <garbege> linenumber <garbage>

XXSample usage:

XXScript started on Fri Jun  6 18:29:09 1986
XX% grep range context.c
XXint cxtrange = 3;
XX		if ((cxtrange = atol(argv[1])) < 1 || cxtrange > 25)
XX			cxtrange = 3;
XX		lolino = (cxtln < cxtrange - 1? 1: cxtln - cxtrange);
XX		hilino = cxtln + cxtrange;

XX% grep -n range /dev/null context.c | context	# /dev/null forces filename
XX**************
XX* context.c:6:int cxtrange = 3;
XX*****
XX  
XX  char curfile[512];
XX  FILE *curfp = NULL;
XX* int cxtrange = 3;
XX  
XX  char *gets();
XX  

XX**************
XX* context.c:20:		if ((cxtrange = atol(argv[1])) < 1 || cxtrange > 25)
XX*****
XX  		exit(1);
XX  	}
XX  	if (argc == 2)
XX* 		if ((cxtrange = atol(argv[1])) < 1 || cxtrange > 25)
XX  			cxtrange = 3;
XX  	while (gets(context) != (char *) 0) {
XX  		for (cp = context; *cp != '.' && *cp != '/' && *cp != '-' && *cp != '_' && !isalnum(*cp); cp++)

XX**************
XX* context.c:21:			cxtrange = 3;
XX*****
XX  	}
XX  	if (argc == 2)
XX  		if ((cxtrange = atol(argv[1])) < 1 || cxtrange > 25)
XX* 			cxtrange = 3;
XX  	while (gets(context) != (char *) 0) {
XX  		for (cp = context; *cp != '.' && *cp != '/' && *cp != '-' && *cp != '_' && !isalnum(*cp); cp++)
XX  			if (*cp == '\0')

XX**************
XX* context.c:49:		lolino = (cxtln < cxtrange - 1? 1: cxtln - cxtrange);
XX*****
XX  		if (*fcp == '\0')
XX  			continue;
XX  		cxtln = atol(fcp);
XX* 		lolino = (cxtln < cxtrange - 1? 1: cxtln - cxtrange);
XX  		hilino = cxtln + cxtrange;
XX  		if (lolino < curln) {
XX  			fseek(curfp, 0L, 0);

XX**************
XX* context.c:50:		hilino = cxtln + cxtrange;
XX*****
XX  			continue;
XX  		cxtln = atol(fcp);
XX  		lolino = (cxtln < cxtrange - 1? 1: cxtln - cxtrange);
XX* 		hilino = cxtln + cxtrange;
XX  		if (lolino < curln) {
XX  			fseek(curfp, 0L, 0);
XX  			curln = 0;

XX% 
XXscript done on Fri Jun  6 18:29:55 1986

XXAlso useful for examining the causes of C errors (although I've received mixed
XXreviews on that; seems that BSD4.2 has a smarter'' program callederrors'').

XXSimply compile context.c -- there are no V7/S5/BSD dependencies that I know
XXof.  Then enjoy.

XX					--Brandon
@//E*O*F README//
chmod u=rw,g=rw,o=rw README
 
echo x - context.c
sed 's/^XX//' > "context.c" <<'@//E*O*F context.c//'
XX#include <stdio.h>
XX#include <ctype.h>

XXchar curfile[512];
XXFILE *curfp = NULL;
XXint cxtrange = 3;

XXchar *gets();

XXmain(argc, argv)
XXchar **argv; {
XX	char context[512], fline[512], *cp, *fcp;
XX	long cxtln, lolino, hilino, curln;

XX	if (argc > 2) {
XX		fprintf(stderr, "Usage: context [nlines] < listfile\n");
XX		exit(1);
XX	}
XX	if (argc == 2)
XX		if ((cxtrange = atol(argv[1])) < 1 || cxtrange > 25)
XX			cxtrange = 3;
XX	while (gets(context) != (char *) 0) {
XX		for (cp = context; *cp != '.' && *cp != '/' && *cp != '-' && *cp != '_' && !isalnum(*cp); cp++)
XX			if (*cp == '\0')
XX				break;
XX		if (*cp == '\0')
XX			continue;
XX		strcpy(fline, cp);
XX		for (fcp = cp, cp = fline; *cp == '_' || *cp == '.' || *cp == '/' || *cp == '-' || isalnum(*cp); cp++, fcp++)
XX			;
XX		if (*cp == '\0')
XX			continue;
XX		*cp = '\0';
XX		if (curfp == (FILE *) 0 || strcmp(curfile, fline) != 0) {
XX			if (curfp != (FILE *) 0)
XX				fclose(curfp);
XX			if ((curfp = fopen(fline, "r")) == (FILE *) 0) {
XX				perror(fline);
XX				continue;
XX			}
XX			strcpy(curfile, fline);
XX			curln = 0;
XX		}
XX		for (; *fcp != '\0' && !isdigit(*fcp); fcp++)
XX			;
XX		if (*fcp == '\0')
XX			continue;
XX		cxtln = atol(fcp);
XX		lolino = (cxtln < cxtrange - 1? 1: cxtln - cxtrange);
XX		hilino = cxtln + cxtrange;
XX		if (lolino < curln) {
XX			fseek(curfp, 0L, 0);
XX			curln = 0;
XX		}
XX		if (cxtln == curln) {		/* already shown */
XX			printf("*****\n* %s\n*****\n\n", context);
XX			continue;
XX		}
XX		printf("**************\n* %s\n*****\n", context);
XX		while (fgets(fline, 512, curfp) != (char *) 0 && ++curln < lolino)
XX			;
XX		if (curln < lolino)
XX			continue;
XX		out(fline, curln == cxtln);
XX		while (fgets(fline, 512, curfp) != (char *) 0 && ++curln <= hilino)
XX			out(fline, curln == cxtln);
XX		putchar('\n');
XX	}
XX}

XXout(s, flg)
XXchar *s; {
XX	printf("%c %s", (flg? '*': ' '), s);
XX}
@//E*O*F context.c//
chmod u=rw,g=rw,o=rw context.c
 
echo Inspecting for damage in transit...
temp=/tmp/sharin$$; dtemp=/tmp/sharout$$
trap "rm -f $temp $dtemp; exit" 0 1 2 3 15
cat > $temp <<\!!!
      81     362    2154 README
      74     291    1772 context.c
     155     653    3926 total
!!!
wc  README context.c | sed 's=[^ ]*/==' | diff -b $temp - >$dtemp
if test -s $dtemp
then echo "Ouch [diff of wc output]:" ; cat $dtemp
else echo "No problems found."
fi
exit 0