really long lines

Makefile

@@ -1,6 +1,6 @@
 include config.mk
 
-LIB = util/enmasse.o util/eprintf.o util/recurse.o
+LIB = util/afgets.o util/enmasse.o util/eprintf.o util/recurse.o
 SRC = basename.c cat.c chown.c date.c dirname.c echo.c false.c grep.c head.c \
       ln.c mkfifo.c pwd.c rm.c sleep.c tee.c touch.c true.c wc.c
 OBJ = $(SRC:.c=.o) $(LIB)
@@ -11,6 +11,7 @@ all: $(BIN)
 
 $(OBJ): util.h
 $(BIN): util.a
+grep: text.h
 
 .o:
 	@echo CC -o $@

grep.c

@@ -4,6 +4,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include "text.h"
 
 static void grep(FILE *, const char *, regex_t *);
 
@@ -66,34 +67,39 @@ main(int argc, char *argv[])
 void
 grep(FILE *fp, const char *str, regex_t *preg)
 {
-	char buf[BUFSIZ];
-	int n, c = 0;
+	char *buf = NULL;
+	long n, c = 0;
+	size_t size = 0;
 
-	for(n = 1; fgets(buf, sizeof buf, fp); n++) {
+	for(n = 1; afgets(&buf, &size, fp); n++) {
 		if(regexec(preg, buf, 0, NULL, 0) ^ vflag)
 			continue;
-		if(mode == 'c')
+		switch(mode) {
+		case 'c':
 			c++;
-		else if(mode == 'l') {
-			puts(str);
 			break;
-		}
-		else if(mode == 'q')
+		case 'l':
+			puts(str);
+			goto end;
+		case 'q':
 			exit(0);
-		else {
+		default:
 			if(many)
 				printf("%s:", str);
 			if(mode == 'n')
-				printf("%d:", n);
+				printf("%ld:", n);
 			fputs(buf, stdout);
+			break;
 		}
 		match = true;
 	}
 	if(mode == 'c')
-		printf("%d\n", c);
+		printf("%ld\n", c);
+end:
 	if(ferror(fp)) {
 		fprintf(stderr, "%s: read error: ", str);
 		perror(NULL);
 		exit(2);
 	}
+	free(buf);
 }

head.c

@@ -1,6 +1,7 @@
 /* See LICENSE file for copyright and license details. */
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <unistd.h>
 #include "util.h"
 
@@ -38,10 +39,13 @@ void
 head(FILE *fp, const char *str, long n)
 {
 	char buf[BUFSIZ];
-	long i;
+	long i = 0;
 
-	for(i = 0; i < n && fgets(buf, sizeof buf, fp); i++)
+	while(i < n && fgets(buf, sizeof buf, fp)) {
 		fputs(buf, stdout);
+		if(buf[strlen(buf)-1] == '\n')
+			i++;
+	}
 	if(ferror(fp))
 		eprintf("%s: read error:", str);
 }

text.h

@@ -0,0 +1,3 @@
+/* See LICENSE file for copyright and license details. */
+
+char *afgets(char **p, size_t *size, FILE *fp);

util/afgets.c

@@ -0,0 +1,24 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "../text.h"
+#include "../util.h"
+
+char *
+afgets(char **p, size_t *size, FILE *fp)
+{
+	char buf[BUFSIZ];
+	size_t n, len = 0;
+
+	while(fgets(buf, sizeof buf, fp)) {
+		len += (n = strlen(buf));
+		if(len+1 > *size && !(*p = realloc(*p, len+1)))
+			eprintf("realloc:");
+		strcpy(&(*p)[len-n], buf);
+
+		if(buf[n-1] == '\n' || feof(fp))
+			break;
+	}
+	return *p;
+}