From 85e0983e73f32a56093617734ace70c7b3d50fed Mon Sep 17 00:00:00 2001
From: hjp <hjp>
Date: Thu, 10 Feb 2000 00:15:28 +0000
Subject: [PATCH] Added to repository (the code is actually from Oct 1998)

---
 shuffle/GNUmakefile |  13 ++++++
 shuffle/shuffle.c   | 107 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 120 insertions(+)
 create mode 100644 shuffle/GNUmakefile
 create mode 100644 shuffle/shuffle.c

diff --git a/shuffle/GNUmakefile b/shuffle/GNUmakefile
new file mode 100644
index 0000000..7762d9e
--- /dev/null
+++ b/shuffle/GNUmakefile
@@ -0,0 +1,13 @@
+include GNUmakevars
+include GNUmakerules
+
+shuffle: shuffle.o
+	$(CC) $^ -lant -o $@
+
+clean:
+	rm -f *.o shuffle core foo bar
+
+install: $(BINDIR)/shuffle
+
+distclean: clean
+	rm -f *.bak *.d
diff --git a/shuffle/shuffle.c b/shuffle/shuffle.c
new file mode 100644
index 0000000..969cbb8
--- /dev/null
+++ b/shuffle/shuffle.c
@@ -0,0 +1,107 @@
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <time.h>
+
+#include <ant/io.h>
+#include <ant/string.h>
+
+char *cmnd;
+
+char **lines;
+int nr_lines;
+int nr_lines_a;
+
+unsigned int seed;
+
+static void usage(void)
+{
+    fprintf(stderr, "Usage: %s [-s seed]\n", cmnd);
+    exit(1);
+}
+
+static void readfile(const char *filename)
+{
+    FILE *fp;
+    char *ln;
+
+    if (STREQ(filename, "-")) {
+        fp = stdin;
+    } else {
+        fp = efopen(filename, "r");
+    }
+    while ((ln = getline(fp))) {
+        if (nr_lines >= nr_lines_a) {
+            nr_lines_a = nr_lines_a * 3 / 2 + 1;
+            assert (nr_lines_a > nr_lines);
+            lines = realloc(lines, nr_lines_a * sizeof(*lines));
+            assert(lines);
+        }
+        lines[nr_lines++] = strdup(ln);
+    }
+    if (fp != stdin) {
+        fclose(fp);
+    }
+}
+
+
+static void shuffle(void) {
+    int i;
+    int j;
+    char *p;
+
+    srand(seed);
+    for (i = 0; i < nr_lines; i++) {
+        j = rand() / ((double)RAND_MAX + 1) * nr_lines;
+        assert (0 <= j && j < nr_lines);
+        p = lines[i];
+        lines[i] = lines[j];
+        lines[j] = p;
+    }
+}
+
+
+static void dump(void) {
+    int i;
+
+    for (i = 0; i < nr_lines; i++) {
+        puts(lines[i]);
+    }
+}
+
+
+int main(int argc, char **argv)
+{
+    int c;
+    int i;
+    char *p;
+
+    cmnd = argv[0];
+
+    seed = time(NULL);
+    while ((c = getopt(argc, argv, "")) != EOF) {
+	switch (c) {
+	case 's':
+            seed = strtoul(optarg, &p, 0);
+            if (p == optarg || *p != '\0') usage();
+            break;
+	case '?':
+	    usage();
+	default:
+	    assert(0);
+	}
+    }
+
+    if (optind == argc) {
+	readfile("-");
+    }
+    for (i = optind; i < argc; i++) {
+	readfile(argv[i]);
+    }
+    shuffle();
+    dump();
+    return 0;
+}