[openib-general] [PATCH] opensm: truncate log file when fs is overflowed

[Sasha Khapyorsky]

In case when OpenSM log file overflows filesystem and write() fails with
'No space left on device' try to truncate the log file and wrap-around
logging.

Signed-off-by: Sasha Khapyorsky <sashak at voltaire.com>
---

 osm/opensm/osm_log.c |   23 +++++++++++++++--------
 1 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/osm/opensm/osm_log.c b/osm/opensm/osm_log.c
index 668e9a6..b4700c8 100644
--- a/osm/opensm/osm_log.c
+++ b/osm/opensm/osm_log.c
@@ -58,6 +58,7 @@ #include <stdarg.h>
 #include <fcntl.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <errno.h>
 
 #ifndef WIN32
 #include <sys/time.h>
@@ -152,6 +153,7 @@ #endif    
     cl_spinlock_acquire( &p_log->lock );
 #ifdef WIN32
     GetLocalTime(&st);
+ _retry:
     ret = fprintf(   p_log->out_port, "[%02d:%02d:%02d:%03d][%04X] -> %s",
                      st.wHour, st.wMinute, st.wSecond, st.wMilliseconds,
                      pid, buffer);
@@ -159,6 +161,7 @@ #ifdef WIN32
 #else
     pid = pthread_self();
     tim = time(NULL);
+ _retry:
     ret = fprintf( p_log->out_port, "%s %02d %02d:%02d:%02d %06d [%04X] -> %s",
                    ((result.tm_mon < 12) && (result.tm_mon >= 0) ? 
                     month_str[result.tm_mon] : "???"),
@@ -166,6 +169,18 @@ #else
                    result.tm_min, result.tm_sec,
                    usecs, pid, buffer);
 #endif /*  WIN32 */
+
+    if (ret >= 0)
+      log_exit_count = 0;
+    else if (errno == ENOSPC && log_exit_count < 3) {
+      int fd = fileno(p_log->out_port);
+      fprintf(stderr, "log write failed: %s. Will truncate the log file.\n",
+              strerror(errno));
+      ftruncate(fd, 0);
+      lseek(fd, 0, SEEK_SET);
+      log_exit_count++;
+      goto _retry;
+    }
     
     /*
       Flush log on errors too.
@@ -174,14 +189,6 @@ #endif /*  WIN32 */
       fflush( p_log->out_port );
     
     cl_spinlock_release( &p_log->lock );
-    
-    if (ret < 0)
-    {
-      if (log_exit_count++ < 10)
-      {
-        fprintf(stderr, "OSM LOG FAILURE! Quota probably exceeded\n");
-      }
-    }
   }
 }