research st: refine skt.

@@ -46,7 +46,6 @@
 #include <sys/mman.h>
 #include "common.h"
 
-
 /* How much space to leave between the stacks, at each end */
 #define REDZONE    _ST_PAGE_SIZE
 
@@ -75,8 +74,9 @@ _st_stack_t *_st_stack_new(int stack_size)
     }
     
     /* Make a new thread stack object. */
-  if ((ts = (_st_stack_t *)calloc(1, sizeof(_st_stack_t))) == NULL)
+    if ((ts = (_st_stack_t *)calloc(1, sizeof(_st_stack_t))) == NULL) {
         return NULL;
+    }
     extra = _st_randomize_stacks ? _ST_PAGE_SIZE : 0;
     ts->vaddr_size = stack_size + 2*REDZONE + extra;
     ts->vaddr = _st_new_stk_segment(ts->vaddr_size);
@@ -103,21 +103,20 @@ _st_stack_t *_st_stack_new(int stack_size)
     return ts;
 }
 
-
 /*
  * Free the stack for the current thread
  */
 void _st_stack_free(_st_stack_t *ts)
 {
-  if (!ts)
+    if (!ts) {
         return;
+    }
     
     /* Put the stack on the free list */
     ST_APPEND_LINK(&ts->links, _st_free_stacks.prev);
     _st_num_free_stacks++;
 }
 
-
 static char *_st_new_stk_segment(int size)
 {
 #ifdef MALLOC_STACK
@@ -127,28 +126,29 @@ static char *_st_new_stk_segment(int size)
     int mmap_flags = MAP_PRIVATE;
     void *vaddr;
     
-#if defined (MD_USE_SYSV_ANON_MMAP)
+    #if defined (MD_USE_SYSV_ANON_MMAP)
     if (zero_fd < 0) {
-    if ((zero_fd = open("/dev/zero", O_RDWR, 0)) < 0)
+        if ((zero_fd = open("/dev/zero", O_RDWR, 0)) < 0) {
             return NULL;
+        }
         fcntl(zero_fd, F_SETFD, FD_CLOEXEC);
     }
-#elif defined (MD_USE_BSD_ANON_MMAP)
+    #elif defined (MD_USE_BSD_ANON_MMAP)
     mmap_flags |= MAP_ANON;
-#else
-#error Unknown OS
-#endif
+    #else
+        #error Unknown OS
+    #endif
     
     vaddr = mmap(NULL, size, PROT_READ | PROT_WRITE, mmap_flags, zero_fd, 0);
-  if (vaddr == (void *)MAP_FAILED)
+    if (vaddr == (void *)MAP_FAILED) {
         return NULL;
+    }
     
-#endif /* MALLOC_STACK */
+#endif
     
     return (char *)vaddr;
 }
 
-
 /* Not used */
 #if 0
 void _st_delete_stk_segment(char *vaddr, int size)
@@ -166,8 +166,9 @@ int st_randomize_stacks(int on)
     int wason = _st_randomize_stacks;
     
     _st_randomize_stacks = on;
-  if (on)
+    if (on) {
         srandom((unsigned int) st_utime());
+    }
     
     return wason;
 }