From c000931794c2af38e263a91b10836b59f50f1296 Mon Sep 17 00:00:00 2001
From: Tom London <tbl@research.uucp>
Date: Sun, 10 Dec 1978 19:37:24 -0500
Subject: [PATCH] Bell 32V development Work on file usr/src/cmd/look.c

Co-Authored-By: John Reiser <jfr@research.uucp>
Synthesized-from: 32v
---
 usr/src/cmd/look.c | 162 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 162 insertions(+)
 create mode 100644 usr/src/cmd/look.c

diff --git a/usr/src/cmd/look.c b/usr/src/cmd/look.c
new file mode 100644
index 0000000000..b2a9980581
--- /dev/null
+++ b/usr/src/cmd/look.c
@@ -0,0 +1,162 @@
+#include <stdio.h>
+#include <ctype.h>
+
+FILE *dfile;
+char *filenam  = "/usr/dict/words";
+
+int fold;
+int dict;
+int tab;
+char entry[250];
+char word[250];
+char key[50];
+
+main(argc,argv)
+char **argv;
+{
+	register c;
+	long top,bot,mid;
+	while(argc>=2 && *argv[1]=='-') {
+		for(;;) {
+			switch(*++argv[1]) {
+			case 'd':
+				dict++;
+				continue;
+			case 'f':
+				fold++;
+				continue;
+			case 't':
+				tab = argv[1][1];
+				if(tab)
+					++argv[1];
+				continue;
+			case 0:
+				break;
+			default:
+				continue;
+			}
+			break;
+		}
+		argc --;
+		argv++;
+	}
+	if(argc<=1)
+		return;
+	if(argc==2) {
+		fold++;
+		dict++;
+	} else
+		filenam = argv[2];
+	dfile = fopen(filenam,"r");
+	if(dfile==NULL) {
+		fprintf(stderr,"look: can't open %s\n",filenam);
+		exit(2);
+	}
+	canon(argv[1],key);
+	bot = 0;
+	fseek(dfile,0L,2);
+	top = ftell(dfile);
+	for(;;) {
+		mid = (top+bot)/2;
+		fseek(dfile,mid,0);
+		do {
+			c = getc(dfile);
+			mid++;
+		} while(c!=EOF && c!='\n');
+		if(!getword(entry))
+			break;
+		canon(entry,word);
+		switch(compare(key,word)) {
+		case -2:
+		case -1:
+		case 0:
+			if(top<=mid)
+				break;
+			top = mid;
+			continue;
+		case 1:
+		case 2:
+			bot = mid;
+			continue;
+		}
+		break;
+	}
+	fseek(dfile,bot,0);
+	while(ftell(dfile)<top) {
+		if(!getword(entry))
+			return;
+		canon(entry,word);
+		switch(compare(key,word)) {
+		case -2:
+			return;
+		case -1:
+		case 0:
+			puts(entry,stdout);
+			break;
+		case 1:
+		case 2:
+			continue;
+		}
+		break;
+	}
+	while(getword(entry)) {
+		canon(entry,word);
+		switch(compare(key,word)) {
+		case -1:
+		case 0:
+			puts(entry,stdout);
+			continue;
+		}
+		break;
+	}
+}
+
+compare(s,t)
+register char *s,*t;
+{
+	for(;*s==*t;s++,t++)
+		if(*s==0)
+			return(0);
+	return(*s==0? -1:
+		*t==0? 1:
+		*s<*t? -2:
+		2);
+}
+
+getword(w)
+char *w;
+{
+	register c;
+	for(;;) {
+		c = getc(dfile);
+		if(c==EOF)
+			return(0);
+		if(c=='\n')
+			break;
+		*w++ = c;
+	}
+	*w = 0;
+	return(1);
+}
+
+canon(old,new)
+char *old,*new;
+{
+	register c;
+	for(;;) {
+		*new = c = *old++;
+		if(c==0||c==tab) {
+			*new = 0;
+			break;
+		}
+		if(dict) {
+			if(!isalnum(c))
+				continue;
+		}
+		if(fold) {
+			if(isupper(c))
+				*new += 'a' - 'A';
+		}
+		new++;
+	}
+}
-- 
2.20.1