svn commit: r322562 - stable/11/usr.bin/grep

[Kyle Evans]

Author: kevans
Date: Wed Aug 16 01:03:04 2017
New Revision: 322562
URL: https://svnweb.freebsd.org/changeset/base/322562

Log:
  MFC r317051: bsdgrep: remove output separators between overlapping segments
  
  Make bsdgrep more sensitive to context overlaps.  If it's printing
  context that either overlaps or is immediately adjacent to another bit
  of context, don't print a separator.
  
  - Non-overlapping segments no longer have two separators between them
  
  - Overlapping segments no longer have separators between them with
    overlapping sections repeated
  
  Approved by:	emaste (mentor, blanket MFC)

Modified:
  stable/11/usr.bin/grep/util.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/usr.bin/grep/util.c
==============================================================================
--- stable/11/usr.bin/grep/util.c	Wed Aug 16 00:55:56 2017	(r322561)
+++ stable/11/usr.bin/grep/util.c	Wed Aug 16 01:03:04 2017	(r322562)
@@ -55,6 +55,9 @@ __FBSDID("$FreeBSD$");
 static int	 linesqueued;
 static int	 procline(struct str *l, int);
 
+static int	 lasta;
+static bool	 ctxover;
+
 bool
 file_matching(const char *fname)
 {
@@ -204,8 +207,10 @@ procfile(const char *fn)
 	strcpy(ln.file, fn);
 	ln.line_no = 0;
 	ln.len = 0;
+	ctxover = false;
 	linesqueued = 0;
 	tail = 0;
+	lasta = 0;
 	ln.off = -1;
 
 	for (c = 0;  c == 0 || !(lflag || qflag); ) {
@@ -227,10 +232,24 @@ procfile(const char *fn)
 			free(f);
 			return (0);
 		}
-		/* Process the file line-by-line */
+
+		/* Process the file line-by-line, enqueue non-matching lines */
 		if ((t = procline(&ln, f->binary)) == 0 && Bflag > 0) {
-			enqueue(&ln);
-			linesqueued++;
+			/* Except don't enqueue lines that appear in -A ctx */
+			if (ln.line_no == 0 || lasta != ln.line_no) {
+				/* queue is maxed to Bflag number of lines */
+				enqueue(&ln);
+				linesqueued++;
+				ctxover = false;
+			} else {
+				/*
+				 * Indicate to procline() that we have ctx
+				 * overlap and make sure queue is empty.
+				 */
+				if (!ctxover)
+					clearqueue();
+				ctxover = true;
+			}
 		}
 		c += t;
 		if (mflag && mcount <= 0)
@@ -385,17 +404,19 @@ procline(struct str *l, int nottext)
 	/* Dealing with the context */
 	if ((tail || c) && !cflag && !qflag && !lflag && !Lflag) {
 		if (c) {
-			if (!first && !prev && !tail && Aflag)
+			if (!first && !prev && !tail && (Bflag || Aflag) &&
+			    !ctxover)
 				printf("--\n");
 			tail = Aflag;
 			if (Bflag > 0) {
-				if (!first && !prev)
-					printf("--\n");
 				printqueue();
+				ctxover = false;
 			}
 			linesqueued = 0;
 			printline(l, ':', matches, m);
 		} else {
+			/* Print -A lines following matches */
+			lasta = l->line_no;
 			printline(l, '-', matches, m);
 			tail--;
 		}