Add circular logging

[vpp.git] / src / vppinfra / maplog.h

diff --git a/src/vppinfra/maplog.h b/src/vppinfra/maplog.h
index 9bc8596..67a83a7 100644 (file)
--- a/src/vppinfra/maplog.h
+++ b/src/vppinfra/maplog.h
@@ -45,12 +45,12 @@ typedef struct
   u8 maplog_major_version;     /**< library major version number */
   u8 maplog_minor_version;     /**< library minor version number */
   u8 maplog_patch_version;     /**< library patch version number */
-  u8 pad;
+  u8 maplog_flag_wrapped;      /**< log has wrapped */
   u32 application_id;          /**< application identifier */
   u8 application_major_version;        /**< application major version number */
   u8 application_minor_version;        /**< application minor version number */
   u8 application_patch_version;        /**< application patch version number */
-  u8 pad2;
+  u8 maplog_flag_circular;     /**< log is circular */
   u32 record_size_in_cachelines; /**< record size in cache lines */
   u32 cacheline_size;           /**< cache line size  */
   u64 file_size_in_records;     /**< file size in records */
@@ -60,7 +60,7 @@ typedef struct
 } clib_maplog_header_t;
 
 #define MAPLOG_MAJOR_VERSION 1
-#define MAPLOG_MINOR_VERSION 0
+#define MAPLOG_MINOR_VERSION 1
 #define MAPLOG_PATCH_VERSION 0
 
 /** Process-private main data structure */
@@ -90,6 +90,8 @@ typedef struct
 
 /* flag bits */
 #define CLIB_MAPLOG_FLAG_INIT  (1<<0)
+#define CLIB_MAPLOG_FLAG_CIRCULAR (1<<1)
+#define CLIB_MAPLOG_FLAG_WRAPPED (1<<2)
 
 /** log initialization structure */
 typedef struct
@@ -102,6 +104,7 @@ typedef struct
   u8 application_major_version;        /**< applcation major version number */
   u8 application_minor_version;        /**< applcation minor version number */
   u8 application_patch_version;        /**< applcation patch version number */
+  u8 maplog_is_circular;       /**< single, circular log */
 } clib_maplog_init_args_t;
 
 /* function prototypes */
@@ -139,9 +142,15 @@ clib_maplog_get_entry (clib_maplog_main_t * mm)
   /* Time to unmap and create a new logfile? */
   if (PREDICT_FALSE ((my_record_index & (mm->file_size_in_records - 1)) == 0))
     {
-      /* Yes, but not the very first time... (;-)... */
-      if (my_record_index)
-       return _clib_maplog_get_entry_slowpath (mm, my_record_index);
+      /* Regular log? Switch file... */
+      if (!(mm->flags & CLIB_MAPLOG_FLAG_CIRCULAR))
+       {
+         /* Yes, but not the very first time... (;-)... */
+         if (my_record_index)
+           return _clib_maplog_get_entry_slowpath (mm, my_record_index);
+       }
+      else                     /* Circular log: set the wrap bit and move along */
+       mm->flags |= CLIB_MAPLOG_FLAG_WRAPPED;
       /* FALLTHROUGH */
     }