Factor out readrune and writerune

Makefile

@@ -20,9 +20,11 @@ HDR =\
 
 LIBUTF = libutf.a
 LIBUTFSRC =\
+	libutf/readrune.c\
 	libutf/rune.c\
 	libutf/runetype.c\
-	libutf/utf.c
+	libutf/utf.c\
+	libutf/writerune.c
 
 LIBUTIL = libutil.a
 LIBUTILSRC =\

expand.c

@@ -47,47 +47,6 @@ main(int argc, char *argv[])
 	return 0;
 }
 
-int
-in(const char *file, FILE *fp, Rune *r)
-{
-	char buf[UTFmax];
-	int c, i;
-
-	c = fgetc(fp);
-	if (ferror(fp))
-		eprintf("%s: read error:", file);
-	if (feof(fp))
-		return 0;
-	if (c < Runeself) {
-		*r = (Rune)c;
-		return 1;
-	}
-	buf[0] = c;
-	for (i = 1; ;) {
-		c = fgetc(fp);
-		if (ferror(fp))
-			eprintf("%s: read error:", file);
-		if (feof(fp))
-			return 0;
-		buf[i++] = c;
-		if (fullrune(buf, i))
-			return chartorune(r, buf);
-	}
-}
-
-static void
-out(Rune *r)
-{
-	char buf[UTFmax];
-	int len;
-
-	if ((len = runetochar(buf, r))) {
-		fwrite(buf, len, 1, stdout);
-		if (ferror(stdout))
-			eprintf("stdout: write error:");
-	}
-}
-
 static int
 expand(const char *file, FILE *fp, int tabstop)
 {
@@ -96,7 +55,7 @@ expand(const char *file, FILE *fp, int tabstop)
 	int bol = 1;
 
 	for (;;) {
-		if (!in(file, fp, &r))
+		if (!readrune(file, fp, &r))
 			break;
 
 		switch (r) {
@@ -115,18 +74,18 @@ expand(const char *file, FILE *fp, int tabstop)
 			if (col)
 				col--;
 			bol = 0;
-			out(&r);
+			writerune(&r);
 			break;
 		case '\n':
 			col = 0;
 			bol = 1;
-			out(&r);
+			writerune(&r);
 			break;
 		default:
 			col++;
 			if (r != ' ')
 				bol = 0;
-			out(&r);
+			writerune(&r);
 			break;
 		}
 	}

libutf/readrune.c

@@ -0,0 +1,46 @@
+/* See LICENSE file for copyright and license details. */
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "../utf.h"
+
+int
+readrune(const char *file, FILE *fp, Rune *r)
+{
+	char buf[UTFmax];
+	int c, i;
+
+	if ((c = fgetc(fp)) == EOF) {
+		if (ferror(fp)) {
+			fprintf(stderr, "%s: read error: %s\n",
+				file, strerror(errno));
+			exit(1);
+		}
+		return 0;
+	}
+
+	if (c < Runeself) {
+		*r = (Rune)c;
+		return 1;
+	}
+
+	buf[0] = c;
+	for (i = 1; ;) {
+		if ((c = fgetc(fp)) == EOF) {
+			if (ferror(fp)) {
+				fprintf(stderr, "%s: read error: %s\n",
+					file, strerror(errno));
+				exit(1);
+			}
+			return 0;
+		}
+		buf[i++] = c;
+		if (fullrune(buf, i)) {
+			chartorune(r, buf);
+			break;
+		}
+	}
+	return 1;
+}

libutf/writerune.c

@@ -0,0 +1,23 @@
+/* See LICENSE file for copyright and license details. */
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "../utf.h"
+
+void
+writerune(Rune *r)
+{
+	char buf[UTFmax];
+	int n;
+
+	if ((n = runetochar(buf, r)) > 0) {
+		fwrite(buf, n, 1, stdout);
+		if (ferror(stdout)) {
+			fprintf(stderr, "stdout: write error: %s\n",
+				strerror(errno));
+			exit(1);
+		}
+	}
+}

utf.h

@@ -18,8 +18,7 @@
  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  * DEALINGS IN THE SOFTWARE.
  */
-
-#include <stddef.h>
+#include <stdio.h>
 
 typedef int Rune;
 
@@ -49,3 +48,6 @@ int isspacerune(Rune);
 int istitlerune(Rune);
 int isupperrune(Rune);
 int isdigitrune(Rune);
+
+int readrune(const char *, FILE *, Rune *);
+void writerune(Rune *);