Introducing thread-safe nxt_random().

src/nxt_lib.c

@@ -11,7 +11,6 @@ nxt_uint_t    nxt_ncpu = 1;
 nxt_uint_t    nxt_pagesize;
 nxt_task_t    nxt_main_task;
 nxt_atomic_t  nxt_task_ident;
-nxt_random_t  nxt_random_data;
 
 nxt_thread_declare_data(nxt_thread_t, nxt_thread_context);
 
@@ -100,7 +99,7 @@ nxt_lib_start(const char *app, char **argv, char ***envp)
 
     nxt_thread_spin_init(nxt_ncpu, 0);
 
-    nxt_random_init(&nxt_random_data);
+    nxt_random_init(&thread->random);
 
     nxt_pagesize = getpagesize();
 

src/nxt_main.h

@@ -175,7 +175,6 @@ NXT_EXPORT extern nxt_uint_t    nxt_ncpu;
 NXT_EXPORT extern nxt_uint_t    nxt_pagesize;
 NXT_EXPORT extern nxt_task_t    nxt_main_task;
 NXT_EXPORT extern nxt_atomic_t  nxt_task_ident;
-NXT_EXPORT extern nxt_random_t  nxt_random_data;
 
 
 #endif /* _NXT_LIB_H_INCLUDED_ */

src/nxt_port_memory.c

@@ -217,7 +217,7 @@ nxt_port_new_port_mmap(nxt_task_t *task, nxt_process_t *process,
     }
 
     p = nxt_sprintf(name, name + sizeof(name), "/nginext.%PI.%uxD",
-                    nxt_pid, nxt_random(&nxt_random_data));
+                    nxt_pid, nxt_random(&task->thread->random));
     *p = '\0';
 
 #if (NXT_HAVE_MEMFD_CREATE)

src/nxt_process.c

@@ -82,7 +82,9 @@ nxt_process_start(nxt_task_t *task, nxt_process_init_t *process)
 
     nxt_process_title(task, "nginext: %s", process->name);
 
-    nxt_random_init(&nxt_random_data);
+    thread = task->thread;
+
+    nxt_random_init(&thread->random);
 
     if (process->user_cred != NULL && getuid() == 0) {
         /* Super-user. */
@@ -93,7 +95,6 @@ nxt_process_start(nxt_task_t *task, nxt_process_init_t *process)
         }
     }
 
-    thread = task->thread;
     rt = thread->runtime;
 
     rt->types |= (1U << process->type);

src/nxt_random.c

@@ -8,8 +8,6 @@
 #include <nxt_main.h>
 
 
-#if !(NXT_HAVE_ARC4RANDOM)
-
 /*
  * The pseudorandom generator based on OpenBSD arc4random.  Although it is
  * usually stated that arc4random uses RC4 pseudorandom generation algorithm
@@ -56,7 +54,7 @@ nxt_random_stir(nxt_random_t *r)
     ssize_t         n;
     struct timeval  tv;
     union {
-        uint32_t    value[3];
+        uint32_t    value[4];
         u_char      bytes[NXT_RANDOM_KEY_SIZE];
     } key;
 
@@ -87,6 +85,7 @@ nxt_random_stir(nxt_random_t *r)
         key.value[0] ^= tv.tv_usec;
         key.value[1] ^= tv.tv_sec;
         key.value[2] ^= nxt_pid;
+        key.value[3] ^= nxt_thread_tid(NULL);
     }
 
     nxt_random_add(r, key.bytes, NXT_RANDOM_KEY_SIZE);
@@ -202,5 +201,3 @@ nxt_random_unit_test(nxt_thread_t *thr)
 }
 
 #endif
-
-#endif

src/nxt_random.h

@@ -8,24 +8,6 @@
 #define _NXT_RANDOM_H_INCLUDED_
 
 
-#if (NXT_HAVE_ARC4RANDOM)
-
-/*
- * arc4random() has been introduced in OpenBSD 2.1 and then was ported
- * to FreeBSD 2.2.6, NetBSD 2.0, MacOSX and SmartOS.
- *
- * arc4random() automatically initializes itself in the first call and
- * then reinitializes itself in the first call in every forked processes.
- */
-
-typedef void  *nxt_random_t;
-
-
-#define nxt_random_init(r)
-#define nxt_random(r)       arc4random()
-
-#else
-
 typedef struct {
     uint8_t  i;
     uint8_t  j;
@@ -41,7 +23,5 @@ uint32_t nxt_random(nxt_random_t *r);
 nxt_int_t nxt_random_unit_test(nxt_thread_t *thr);
 #endif
 
-#endif
-
 
 #endif /* _NXT_RANDOM_H_INCLUDED_ */

src/nxt_router.c

@@ -1655,7 +1655,7 @@ nxt_router_process_http_request(nxt_task_t *task, nxt_conn_t *c,
     engine = task->thread->engine;
 
     do {
-        req_id = nxt_random(&nxt_random_data);
+        req_id = nxt_random(&task->thread->random);
     } while (nxt_event_engine_request_find(engine, req_id) != NULL);
 
     rc = nxt_conn_request_add(c, req_id);

src/nxt_thread.c

@@ -160,6 +160,8 @@ nxt_thread_init(void)
         nxt_thread_time_update(thr);
     }
 
+    nxt_random_init(&thr->random);
+
     return thr;
 }
 

src/nxt_thread.h

@@ -188,6 +188,8 @@ struct nxt_thread_s {
      * engine->fibers, its placement here eliminates 2 memory accesses.
      */
     nxt_fiber_t              *fiber;
+
+    nxt_random_t             random;
 };