From 94435942f63652be86db86e43b5f7425d3e56ea1 Mon Sep 17 00:00:00 2001
From: Arnaud Giersch <arnaud.giersch@iut-bm.univ-fcomte.fr>
Date: Sat, 5 Nov 2011 22:37:12 +0100
Subject: [PATCH] Improve xbt_log_layout_simple_doit().

Make it simpler and slightly faster.
---
 src/xbt/xbt_log_layout_simple.c | 66 +++++++++++++++------------------
 1 file changed, 30 insertions(+), 36 deletions(-)

diff --git a/src/xbt/xbt_log_layout_simple.c b/src/xbt/xbt_log_layout_simple.c
index ac603b446d..30108d4697 100644
--- a/src/xbt/xbt_log_layout_simple.c
+++ b/src/xbt/xbt_log_layout_simple.c
@@ -20,63 +20,57 @@ extern int xbt_log_no_loc;
 
 static double simple_begin_of_time = -1;
 
-#define XBT_LOG_BUFF_SIZE (ev->buffer_size)
-
-/* only used after the format using: we suppose that the buffer is big enough to display our data */
-#undef check_overflow
-#define check_overflow \
-  if (p - ev->buffer >= XBT_LOG_BUFF_SIZE) { /* buffer overflow */ \
-    return 0;                                                      \
-  } else ((void)0)
+#define check_overflow(len)                                             \
+  if ((rem_size -= (len)) > 0) {                                        \
+    p += (len);                                                         \
+  } else                                                                \
+    return 0
 
 static int xbt_log_layout_simple_doit(xbt_log_layout_t l,
                                       xbt_log_event_t ev,
                                       const char *fmt)
 {
-  char *p;
-  const char *procname = NULL;
-  xbt_assert(ev->priority >= 0,
-              "Negative logging priority naturally forbidden");
-  xbt_assert(ev->priority < sizeof(xbt_log_priority_names),
-              "Priority %d is greater than the biggest allowed value",
-              ev->priority);
-
-  p = ev->buffer;
-  p += snprintf(p, XBT_LOG_BUFF_SIZE - (p - ev->buffer), "[");
-  check_overflow;
+  char *p = ev->buffer;
+  int rem_size = ev->buffer_size;
+  const char *procname;
+  int len;
+
+  *p = '[';
+  check_overflow(1);
 
   /* Display the proc info if available */
   procname = xbt_procname();
-  if (strlen(procname)) {
-    p += snprintf(p, XBT_LOG_BUFF_SIZE - (p - ev->buffer), "%s:%s:(%d) ",
-                  gras_os_myname(), procname, (*xbt_getpid) ());
-    check_overflow;
+  if (*procname) {
+    len = snprintf(p, rem_size, "%s:%s:(%d) ",
+                   gras_os_myname(), procname, xbt_getpid());
+    check_overflow(len);
   }
 
   /* Display the date */
-  p += snprintf(p, XBT_LOG_BUFF_SIZE - (p - ev->buffer), "%f] ",
-                gras_os_time() - simple_begin_of_time);
-  check_overflow;
+  len = snprintf(p, rem_size, "%f] ",
+                 gras_os_time() - simple_begin_of_time);
+  check_overflow(len);
 
   /* Display file position if not INFO */
   if (ev->priority != xbt_log_priority_info && !xbt_log_no_loc) {
-    p += snprintf(p, XBT_LOG_BUFF_SIZE - (p - ev->buffer), "%s:%d: ",
-                  ev->fileName, ev->lineNum);
-    check_overflow;
+    len = snprintf(p, rem_size, "%s:%d: ",
+                   ev->fileName, ev->lineNum);
+    check_overflow(len);
   }
 
   /* Display category name */
-  p += snprintf(p, XBT_LOG_BUFF_SIZE - (p - ev->buffer), "[%s/%s] ",
-                ev->cat->name, xbt_log_priority_names[ev->priority]);
-  check_overflow;
+  len = snprintf(p, rem_size, "[%s/%s] ",
+                 ev->cat->name, xbt_log_priority_names[ev->priority]);
+  check_overflow(len);
 
   /* Display user-provided message */
-  p += vsnprintf(p, XBT_LOG_BUFF_SIZE - (p - ev->buffer), fmt, ev->ap);
-  check_overflow;
+  len = vsnprintf(p, rem_size, fmt, ev->ap);
+  check_overflow(len);
 
   /* End it */
-  p += snprintf(p, XBT_LOG_BUFF_SIZE - (p - ev->buffer), "\n");
-  check_overflow;
+  *p = '\n';
+  check_overflow(1);
+  *p = '\0';
 
   return 1;
 }
-- 
2.20.1