no reason to die when posixfadvise is not sucessful

[rrdtool.git] / src / rrd_open.c

diff --git a/src/rrd_open.c b/src/rrd_open.c
index 80f9a04..6a3cf34 100644 (file)
--- a/src/rrd_open.c
+++ b/src/rrd_open.c
@@ -1,5 +1,5 @@
 /*****************************************************************************
- * RRDtool 1.2.23  Copyright by Tobi Oetiker, 1997-2007
+ * RRDtool 1.2.99907080300  Copyright by Tobi Oetiker, 1997-2007
  *****************************************************************************
  * rrd_open.c  Open an RRD File
  *****************************************************************************
@@ -140,11 +140,7 @@ rrd_file_t *rrd_open(
        When we stop reading, it is highly unlikely that we start up again.
        In this manner we actually save time and diskaccess (and buffer cache).
        Thanks to Dave Plonka for the Idea of using POSIX_FADV_RANDOM here. */
-    if (0 != posix_fadvise(rrd_file->fd, 0, 0, POSIX_FADV_RANDOM)) {
-        rrd_set_error("setting POSIX_FADV_RANDOM on '%s': %s", file_name,
-                      rrd_strerror(errno));
-        goto out_close;
-    }
+    posix_fadvise(rrd_file->fd, 0, 0, POSIX_FADV_RANDOM);
 #endif
 
 /*
@@ -381,6 +377,9 @@ int rrd_close(
     int       ret;
 
 #ifdef HAVE_MMAP
+    ret = msync(rrd_file->file_start, rrd_file->file_len,MS_ASYNC);
+    if (ret != 0)
+        rrd_set_error("msync rrd_file: %s", rrd_strerror(errno));
     ret = munmap(rrd_file->file_start, rrd_file->file_len);
     if (ret != 0)
         rrd_set_error("munmap rrd_file: %s", rrd_strerror(errno));
@@ -440,8 +439,13 @@ inline ssize_t rrd_read(
 {
 #ifdef HAVE_MMAP
     size_t    _cnt = count;
-    ssize_t   _surplus = rrd_file->pos + _cnt - rrd_file->file_len;
+    ssize_t   _surplus;
 
+    if (rrd_file->pos > rrd_file->file_len || _cnt == 0) /* EOF */
+       return 0;
+    if (buf == NULL)
+       return -1; /* EINVAL */
+    _surplus = rrd_file->pos + _cnt - rrd_file->file_len;
     if (_surplus > 0) { /* short read */
         _cnt -= _surplus;
     }
@@ -464,7 +468,7 @@ inline ssize_t rrd_read(
 
 /* write count bytes from buffer buf to the current position
  * rrd_file->pos of rrd_file->fd.
- * Returns the number of bytes written.  */
+ * Returns the number of bytes written or <0 on error.  */
 
 inline ssize_t rrd_write(
     rrd_file_t *rrd_file,
@@ -472,6 +476,10 @@ inline ssize_t rrd_write(
     size_t count)
 {
 #ifdef HAVE_MMAP
+    if (count == 0)
+       return 0;
+    if (buf == NULL)
+       return -1; /* EINVAL */
     memcpy(rrd_file->file_start + rrd_file->pos, buf, count);
     rrd_file->pos += count;
     return count;       /* mimmic write() semantics */