sbase

commit 7627a5069cb14c66d8ba964e4a02ce5b56ff6180
parent e34ce441928a4670b5e62c0fa8f0f0f7ce631965
Author: sin <sin@2f30.org>
Date:   Thu, 20 Nov 2014 14:47:26 +0000

Implement grep -x

Diffstat:
M
grep.1
 | 
6
+++++-
M
grep.c
 | 
23
++++++++++++++++++++---

2 files changed, 25 insertions(+), 4 deletions(-)
diff --git a/grep.1 b/grep.1
@@ -3,7 +3,7 @@
 grep \- search files for a pattern
 .SH SYNOPSIS
 .B grep
-.RB [ \-EFHchilnqsv ]
+.RB [ \-EFHchilnqsvx ]
 .RB [ \-e
 .I pattern ]
 .I pattern
@@ -64,5 +64,9 @@ Suppress the error messages ordinarily written for nonexistent or unreadable fil
 Selects lines which do
 .B not
 Match the pattern.
+.TP
+.B \-x
+Consider only input lines that use all characters in the line excluding the terminating <newline> to
+match an entire fixed string or regular expression to be matching lines.
 .SH SEE ALSO
 .IR regex (7)
diff --git a/grep.c b/grep.c
@@ -20,6 +20,7 @@ static int eflag;
 static int hflag;
 static int sflag;
 static int vflag;
+static int xflag;
 static int many;
 static char mode;
 
@@ -34,7 +35,7 @@ static SLIST_HEAD(phead, pattern) phead;
 static void
 usage(void)
 {
-	enprintf(Error, "usage: %s [-EFHcilnqsv] [-e pattern] pattern [files...]\n", argv0);
+	enprintf(Error, "usage: %s [-EFHcilnqsvx] [-e pattern] pattern [files...]\n", argv0);
 }
 
 int
@@ -78,6 +79,9 @@ main(int argc, char *argv[])
 	case 'v':
 		vflag = 1;
 		break;
+	case 'x':
+		xflag = 1;
+		break;
 	default:
 		usage();
 	} ARGEND;
@@ -128,9 +132,19 @@ static void
 addpattern(const char *pattern)
 {
 	struct pattern *pnode;
+	char *tmp;
 
 	pnode = emalloc(sizeof(*pnode));
-	pnode->pattern = estrdup(pattern);
+	if (!Fflag && xflag) {
+		tmp = emalloc(strlen(pattern) + 3);
+		snprintf(tmp, strlen(pattern) + 3, "%s%s%s",
+			 pattern[0] == '^' ? "" : "^",
+			 pattern,
+			 pattern[strlen(pattern) - 1] == '$' ? "" : "$");
+		pnode->pattern = tmp;
+	} else {
+		pnode->pattern = estrdup(pattern);
+	}
 	SLIST_INSERT_HEAD(&phead, pnode, entry);
 }
 
@@ -152,7 +166,10 @@ grep(FILE *fp, const char *str)
 				if (regexec(&pnode->preg, buf, 0, NULL, 0) ^ vflag)
 					continue;
 			} else {
-				match = strstr(buf, pnode->pattern) ? Match : NoMatch;
+				if (!xflag)
+					match = strstr(buf, pnode->pattern) ? Match : NoMatch;
+				else
+					match = strcmp(buf, pnode->pattern);
 				if (match ^ vflag)
 					continue;
 			}