Merge pull request #2088 from wiredtiger/rand-strict-alias

SERVER-19340 Avoid type aliasing in the random number generator.
(cherry picked from commit 3ec45a7204e01a5ac176550fdfef30a7402046e8)

5 files changed, 44 insertions, 12 deletions

diff --git a/test/checkpoint/workers.c b/test/checkpoint/workers.c
index 393532f8e22..5cd2ef4e97b 100644
--- a/test/checkpoint/workers.c
+++ b/test/checkpoint/workers.c
@@ -172,13 +172,13 @@ real_worker(void)
 {
 	WT_CURSOR **cursors;
 	WT_SESSION *session;
-	uint32_t rnd[2];
+	WT_RAND_STATE rnd;
 	u_int i, keyno;
 	int j, ret, t_ret;
 
 	ret = t_ret = 0;
 
-	__wt_random_init(rnd);
+	__wt_random_init(&rnd);
 
 	if ((cursors = calloc(
 	    (size_t)(g.ntables), sizeof(WT_CURSOR *))) == NULL)
@@ -203,7 +203,7 @@ real_worker(void)
 			    "real_worker:begin_transaction", ret, 1);
 			goto err;
 		}
-		keyno = __wt_random(rnd) % g.nkeys + 1;
+		keyno = __wt_random(&rnd) % g.nkeys + 1;
 		for (j = 0; j < g.ntables; j++) {
 			if ((ret = worker_op(cursors[j], keyno, i)) != 0)
 				break;
diff --git a/test/format/format.h b/test/format/format.h
index f6e7a83470e..a72ad6fc66e 100644
--- a/test/format/format.h
+++ b/test/format/format.h
@@ -159,6 +159,8 @@ typedef struct {
 
 	pthread_rwlock_t backup_lock;		/* Hot backup running */
 
+	WT_RAND_STATE rnd;			/* Global RNG state */
+
 	/*
 	 * We have a list of records that are appended, but not yet "resolved",
 	 * that is, we haven't yet incremented the g.rows value to reflect the
@@ -262,6 +264,8 @@ typedef struct {
 extern GLOBAL g;
 
 typedef struct {
+	WT_RAND_STATE rnd;			/* thread RNG state */
+
 	uint64_t search;			/* operations */
 	uint64_t insert;
 	uint64_t update;
@@ -299,15 +303,18 @@ void	 config_file(const char *);
 void	 config_print(int);
 void	 config_setup(void);
 void	 config_single(const char *, int);
+void	 fclose_and_clear(FILE **);
+void	 key_gen(uint8_t *, size_t *, uint64_t);
+void	 key_gen_insert(WT_RAND_STATE *, uint8_t *, size_t *, uint64_t);
+void	 key_gen_setup(uint8_t **);
 void	 key_len_setup(void);
 void	 key_gen_setup(uint8_t **);
 void	 key_gen(uint8_t *, size_t *, uint64_t, int);
 void	 path_setup(const char *);
-uint32_t rng(void);
-void	 rng_init(void);
+uint32_t rng(WT_RAND_STATE *);
 void	 track(const char *, uint64_t, TINFO *);
-void	 val_gen_setup(uint8_t **);
-void	 value_gen(uint8_t *, size_t *, uint64_t);
+void	 val_gen(WT_RAND_STATE *, uint8_t *, size_t *, uint64_t);
+void	 val_gen_setup(WT_RAND_STATE *, uint8_t **);
 void	 wts_close(void);
 void	 wts_create(void);
 void	 wts_dump(const char *, int);
@@ -324,3 +331,13 @@ void	 die(int, const char *, ...)
 __attribute__((__noreturn__))
 #endif
 ;
+
+/*
+ * mmrand --
+ *	Return a random value between a min/max pair.
+ */
+static inline uint32_t
+mmrand(WT_RAND_STATE *rnd, u_int min, u_int max)
+{
+	return (rng(rnd) % (((max) + 1) - (min)) + (min));
+}
diff --git a/test/format/ops.c b/test/format/ops.c
index 5fd992e9952..84ed02a8750 100644
--- a/test/format/ops.c
+++ b/test/format/ops.c
@@ -191,7 +191,7 @@ wts_ops(int lastrun)
  *	Return the current session configuration.
  */
 static const char *
-ops_session_config(void)
+ops_session_config(WT_RAND_STATE *rnd)
 {
 	u_int v;
 
diff --git a/test/format/util.c b/test/format/util.c
index 186105ae30b..d9bbdbe330f 100644
--- a/test/format/util.c
+++ b/test/format/util.c
@@ -33,7 +33,7 @@
 #endif
 
 static inline uint32_t
-kv_len(uint64_t keyno, uint32_t min, uint32_t max)
+kv_len(WT_RAND_STATE *rnd, uint64_t keyno, uint32_t min, uint32_t max)
 {
 	/*
 	 * Focus on relatively small key/value items, admitting the possibility
@@ -110,10 +110,22 @@ key_gen(uint8_t *key, size_t *sizep, uint64_t keyno, int insert)
 	*sizep = (size_t)len;
 }
 
+void
+key_gen(uint8_t *key, size_t *sizep, uint64_t keyno)
+{
+	key_gen_common(key, sizep, keyno, 0);
+}
+
+void
+key_gen_insert(WT_RAND_STATE *rnd, uint8_t *key, size_t *sizep, uint64_t keyno)
+{
+	key_gen_common(key, sizep, keyno, (int)mmrand(rnd, 1, 15));
+}
+
 static uint32_t val_dup_data_len;	/* Length of duplicate data items */
 
 void
-val_gen_setup(uint8_t **valp)
+val_gen_setup(WT_RAND_STATE *rnd, uint8_t **valp)
 {
 	uint8_t *val;
 	size_t i, len;
@@ -140,7 +152,7 @@ val_gen_setup(uint8_t **valp)
 }
 
 void
-value_gen(uint8_t *val, size_t *sizep, uint64_t keyno)
+val_gen(WT_RAND_STATE *rnd, uint8_t *val, size_t *sizep, uint64_t keyno)
 {
 	/*
 	 * Fixed-length records: take the low N bits from the last digit of
@@ -350,7 +362,7 @@ path_setup(const char *home)
  *	Return a random number.
  */
 uint32_t
-rng(void)
+rng(WT_RAND_STATE *rnd)
 {
 	char buf[64];
 	uint32_t r;
diff --git a/test/thread/rw.c b/test/thread/rw.c
index 08cf63f435a..833e514cf0b 100644
--- a/test/thread/rw.c
+++ b/test/thread/rw.c
@@ -34,6 +34,9 @@ static void *writer(void *);
 
 typedef struct {
 	char *name;				/* object name */
+	u_int nops;				/* Thread op count */
+
+	WT_RAND_STATE rnd;			/* RNG */
 
 	int remove;				/* cursor.remove */
 	int update;				/* cursor.update */