klib: add rand()

2018-03-18 14:03:00 +08:00 · 2018-03-18 14:03:00 +08:00 · 00093b3867
parent ebd84e651e
commit 00093b3867
2 changed files with 12 additions and 0 deletions
--- a/libs/klib/Makefile
+++ b/libs/klib/Makefile
@ -2,5 +2,6 @@ NAME = klib
 SRCS = src/printk.c \
       src/string.c \
       src/cpp.c \
+       src/stdlib.c \
       src/io.c
 include $(AM_HOME)/Makefile.lib
--- a/libs/klib/src/stdlib.c
+++ b/libs/klib/src/stdlib.c
@ -0,0 +1,11 @@
+static unsigned long int next = 1;
+
+int rand(void) {
+  // RAND_MAX assumed to be 32767
+  next = next * 1103515245 + 12345;
+  return (unsigned int)(next/65536) % 32768;
+}
+
+void srand(unsigned int seed) {
+  next = seed;
+}