1 files changed, 97 insertions, 0 deletions
diff --git a/util/sbase/comm.c b/util/sbase/comm.c
new file mode 100644
index 00000000..fbd50d9b
--- /dev/null
+++ b/util/sbase/comm.c
@@ -0,0 +1,97 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "text.h"
+#include "util.h"
+
+static int show = 0x07;
+
+static void
+printline(int pos, struct line *line)
+{
+	int i;
+
+	if (!(show & (0x1 << pos)))
+		return;
+
+	for (i = 0; i < pos; i++) {
+		if (show & (0x1 << i))
+			putchar('\t');
+	}
+	fwrite(line->data, 1, line->len, stdout);
+}
+
+static void
+usage(void)
+{
+	eprintf("usage: %s [-123] file1 file2\n", argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+	FILE *fp[2];
+	static struct line line[2];
+	size_t linecap[2] = { 0, 0 };
+	ssize_t len;
+	int ret = 0, i, diff = 0, seenline = 0;
+
+	ARGBEGIN {
+	case '1':
+	case '2':
+	case '3':
+		show &= 0x07 ^ (1 << (ARGC() - '1'));
+		break;
+	default:
+		usage();
+	} ARGEND
+
+	if (argc != 2)
+		usage();
+
+	for (i = 0; i < 2; i++) {
+		if (!strcmp(argv[i], "-")) {
+			argv[i] = "<stdin>";
+			fp[i] = stdin;
+		} else if (!(fp[i] = fopen(argv[i], "r"))) {
+			eprintf("fopen %s:", argv[i]);
+		}
+	}
+
+	for (;;) {
+		for (i = 0; i < 2; i++) {
+			if (diff && i == (diff < 0))
+				continue;
+			if ((len = getline(&(line[i].data), &linecap[i],
+			                   fp[i])) > 0) {
+				line[i].len = len;
+				seenline = 1;
+				continue;
+			}
+			if (ferror(fp[i]))
+				eprintf("getline %s:", argv[i]);
+			if ((diff || seenline) && line[!i].data[0])
+				printline(!i, &line[!i]);
+			while ((len = getline(&(line[!i].data), &linecap[!i],
+			                      fp[!i])) > 0) {
+				line[!i].len = len;
+				printline(!i, &line[!i]);
+			}
+			if (ferror(fp[!i]))
+				eprintf("getline %s:", argv[!i]);
+			goto end;
+		}
+		diff = linecmp(&line[0], &line[1]);
+		LIMIT(diff, -1, 1);
+		seenline = 0;
+		printline((2 - diff) % 3, &line[MAX(0, diff)]);
+	}
+end:
+	ret |= fshut(fp[0], argv[0]);
+	ret |= (fp[0] != fp[1]) && fshut(fp[1], argv[1]);
+	ret |= fshut(stdout, "<stdout>");
+
+	return ret;
+}