From 65c411dcb3fd33122cbc314ca5b2a94542bc1e87 Mon Sep 17 00:00:00 2001
From: Charles Cabergs <me@cacharle.xyz>
Date: Sat, 22 Aug 2020 20:09:13 +0200
Subject: Added shuf with trand

---
 .gitmodules |  3 +++
 Makefile    | 10 +++++++++-
 src/shuf.c  |  8 ++++++++
 trand       |  1 +
 4 files changed, 21 insertions(+), 1 deletion(-)
 create mode 100644 .gitmodules
 create mode 160000 trand

diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..e5ead97
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "trand"]
+	path = trand
+	url = https://github.com/SaltyMilk/trand
diff --git a/Makefile b/Makefile
index edb7787..450a5f4 100644
--- a/Makefile
+++ b/Makefile
@@ -6,7 +6,8 @@ CCFLAGS = -Wall -Wextra -Wpedantic
 
 all: prebuild $(BINDIR)/basename $(BINDIR)/chown $(BINDIR)/cut $(BINDIR)/head \
 		$(BINDIR)/mkdir $(BINDIR)/mv $(BINDIR)/rm $(BINDIR)/seq \
-		$(BINDIR)/shuf $(BINDIR)/tee $(BINDIR)/tr
+		$(BINDIR)/shuf $(BINDIR)/tee $(BINDIR)/tr \
+		$(BINDIR)/shuf_trand
 
 prebuild:
 	mkdir -vp $(BINDIR)
@@ -44,6 +45,13 @@ $(BINDIR)/tee: $(SRCDIR)/tee.c
 $(BINDIR)/tr: $(SRCDIR)/tr.c
 	$(CC) $(CCFLAGS) -o $@ $^
 
+#### shuf using trand
+TRAND_PATH = trand
+
+$(BINDIR)/shuf_trand: $(SRCDIR)/shuf.c
+	make --no-print-directory -C $(TRAND_PATH)
+	$(CC) $(CCFLAGS) -o $@ $^ -DUSE_TRAND -I$(TRAND_PATH) -L$(TRAND_PATH) -ltrand -lpthread
+
 clean:
 	rm -vf $(BINDIR)/*
 
diff --git a/src/shuf.c b/src/shuf.c
index 5b4808a..e97f1f0 100644
--- a/src/shuf.c
+++ b/src/shuf.c
@@ -8,6 +8,10 @@
 #include <errno.h>
 #include <limits.h>
 
+#ifdef USE_TRAND
+# include "trand.h"
+#endif
+
 #define NUMBER_LEN(x) strlen(#x);
 
 static char *g_name = "shuf";
@@ -192,7 +196,11 @@ int main(int argc, char **argv)
 	}
 	for (size_t i = lines.len - 1; i > 0; i--)
 	{
+#ifndef USE_TRAND
 		size_t j = rand() % i;
+#else
+		size_t j = trand() % i;
+#endif
 		char *tmp = lines.data[i];
 		lines.data[i] = lines.data[j];
 		lines.data[j] = tmp;
diff --git a/trand b/trand
new file mode 160000
index 0000000..583ad1c
--- /dev/null
+++ b/trand
@@ -0,0 +1 @@
+Subproject commit 583ad1cbe5d1ad9c0a64bbf8180aec21a68463e0
-- 
cgit