X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=src%2Frrd_open.c;h=e407acc10a806b95bdff0838ca0b5b88078c6adb;hb=401ee75cb9db4973161d9bf6e83e586087bd7769;hp=0c51577ba6114da91e89c6d7a2a700fd689830fb;hpb=b5982674ca6703df1ba19dfd18409081e946f0e9;p=rrdtool.git

diff --git a/src/rrd_open.c b/src/rrd_open.c
index 0c51577..e407acc 100644
--- a/src/rrd_open.c
+++ b/src/rrd_open.c
@@ -1,5 +1,5 @@
 /*****************************************************************************
- * RRDtool 1.3.1  Copyright by Tobi Oetiker, 1997-2008
+ * RRDtool 1.3.2  Copyright by Tobi Oetiker, 1997-2008
  *****************************************************************************
  * rrd_open.c  Open an RRD File
  *****************************************************************************
@@ -21,16 +21,30 @@
 /* the cast to void* is there to avoid this warning seen on ia64 with certain
    versions of gcc: 'cast increases required alignment of target type'
 */
-#define __rrd_read(dst, dst_t, cnt) \
+#define __rrd_read(dst, dst_t, cnt) { \
+	size_t wanted = sizeof(dst_t)*(cnt); \
+	if (offset + wanted > rrd_file->file_len) { \
+		rrd_set_error("reached EOF while loading header " #dst); \
+		goto out_nullify_head; \
+	} \
 	(dst) = (dst_t*)(void*) (data + offset); \
-	offset += sizeof(dst_t) * (cnt)
+	offset += wanted; \
+    }
 #else
-#define __rrd_read(dst, dst_t, cnt) \
-	if ((dst = malloc(sizeof(dst_t)*(cnt))) == NULL) { \
+#define __rrd_read(dst, dst_t, cnt) { \
+	size_t wanted = sizeof(dst_t)*(cnt); \
+        size_t got; \
+	if ((dst = malloc(wanted)) == NULL) { \
 		rrd_set_error(#dst " malloc"); \
 		goto out_nullify_head; \
 	} \
-	offset += read (rrd_file->fd, dst, sizeof(dst_t)*(cnt))
+        got = read (rrd_file->fd, dst, wanted); \
+	if (got != wanted) { \
+		rrd_set_error("short read while reading header " #dst); \
+                goto out_nullify_head; \
+	} \
+	offset += got; \
+    }
 #endif
 
 /* get the address of the start of this page */
@@ -58,7 +72,7 @@ rrd_file_t *rrd_open(
 #ifdef HAVE_MMAP
     ssize_t   _page_size = sysconf(_SC_PAGESIZE);
     int       mm_prot = PROT_READ, mm_flags = 0;
-    char     *data;
+    char     *data = MAP_FAILED;
 #endif
     off_t     offset = 0;
     struct stat statb;
@@ -257,11 +271,34 @@ rrd_file_t *rrd_open(
 
     rrd_file->header_len = offset;
     rrd_file->pos = offset;
+
+    {
+      unsigned long row_cnt = 0;
+      unsigned long i;
+
+      for (i=0; i<rrd->stat_head->rra_cnt; i++)
+        row_cnt += rrd->rra_def[i].row_cnt;
+
+      off_t correct_len = rrd_file->header_len +
+        sizeof(rrd_value_t) * row_cnt * rrd->stat_head->ds_cnt;
+
+      if (correct_len > rrd_file->file_len)
+      {
+        rrd_set_error("'%s' is too small (should be %ld bytes)",
+                      file_name, (long long) correct_len);
+        goto out_nullify_head;
+      }
+    }
+
   out_done:
     return (rrd_file);
   out_nullify_head:
     rrd->stat_head = NULL;
   out_close:
+#ifdef HAVE_MMAP
+    if (data != MAP_FAILED)
+      munmap(data, rrd_file->file_len);
+#endif
     close(rrd_file->fd);
   out_free:
     free(rrd_file);
@@ -314,6 +351,41 @@ void mincore_print(
 }
 #endif                          /* defined DEBUG && DEBUG > 1 */
 
+/*
+ * get exclusive lock to whole file.
+ * lock gets removed when we close the file
+ *
+ * returns 0 on success
+ */
+int rrd_lock(
+    rrd_file_t *file)
+{
+    int       rcstat;
+
+    {
+#if defined(_WIN32) && !defined(__CYGWIN__) && !defined(__CYGWIN32__)
+        struct _stat st;
+
+        if (_fstat(file->fd, &st) == 0) {
+            rcstat = _locking(file->fd, _LK_NBLCK, st.st_size);
+        } else {
+            rcstat = -1;
+        }
+#else
+        struct flock lock;
+
+        lock.l_type = F_WRLCK;  /* exclusive write lock */
+        lock.l_len = 0; /* whole file */
+        lock.l_start = 0;   /* start of file */
+        lock.l_whence = SEEK_SET;   /* end of file */
+
+        rcstat = fcntl(file->fd, F_SETLK, &lock);
+#endif
+    }
+
+    return (rcstat);
+}
+
 
 /* drop cache except for the header and the active pages */
 void rrd_dontneed(
@@ -321,12 +393,19 @@ void rrd_dontneed(
     rrd_t *rrd)
 {
 #if defined USE_MADVISE || defined HAVE_POSIX_FADVISE
-    unsigned long dontneed_start;
-    unsigned long rra_start;
-    unsigned long active_block;
+    off_t dontneed_start;
+    off_t rra_start;
+    off_t active_block;
     unsigned long i;
     ssize_t   _page_size = sysconf(_SC_PAGESIZE);
 
+    if (rrd_file == NULL) {
+#if defined DEBUG && DEBUG
+	    fprintf (stderr, "rrd_dontneed: Argument 'rrd_file' is NULL.\n");
+#endif
+	    return;
+    }
+
 #if defined DEBUG && DEBUG > 1
     mincore_print(rrd_file, "before");
 #endif
@@ -363,14 +442,19 @@ void rrd_dontneed(
             rrd->rra_def[i].row_cnt * rrd->stat_head->ds_cnt *
             sizeof(rrd_value_t);
     }
+
+    if (dontneed_start < rrd_file->file_len) {
 #ifdef USE_MADVISE
-    madvise(rrd_file->file_start + dontneed_start,
-            rrd_file->file_len - dontneed_start, MADV_DONTNEED);
+	    madvise(rrd_file->file_start + dontneed_start,
+		    rrd_file->file_len - dontneed_start, MADV_DONTNEED);
 #endif
 #ifdef HAVE_POSIX_FADVISE
-    posix_fadvise(rrd_file->fd, dontneed_start,
-                  rrd_file->file_len - dontneed_start, POSIX_FADV_DONTNEED);
+	    posix_fadvise(rrd_file->fd, dontneed_start,
+			  rrd_file->file_len - dontneed_start,
+			  POSIX_FADV_DONTNEED);
 #endif
+    }
+
 #if defined DEBUG && DEBUG > 1
     mincore_print(rrd_file, "after");
 #endif