This patch introduces a feature whereby rrdcached will disallow updates

[rrdtool.git] / src / rrd_open.c

diff --git a/src/rrd_open.c b/src/rrd_open.c
index 88b50df..f262413 100644 (file)
--- a/src/rrd_open.c
+++ b/src/rrd_open.c
@@ -1,5 +1,5 @@
 /*****************************************************************************
- * RRDtool 1.3rc8  Copyright by Tobi Oetiker, 1997-2008
+ * RRDtool 1.3.2  Copyright by Tobi Oetiker, 1997-2008
  *****************************************************************************
  * rrd_open.c  Open an RRD File
  *****************************************************************************
@@ -21,20 +21,34 @@
 /* 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 */
-#if defined USE_MADVISE || defined HAVE_POSIX_FADVISE 
+#if defined USE_MADVISE || defined HAVE_POSIX_FADVISE
 #ifndef PAGE_START
 #define PAGE_START(addr) ((addr)&(~(_page_size-1)))
 #endif
@@ -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;
@@ -116,6 +130,9 @@ rrd_file_t *rrd_open(
         mm_flags |= MAP_NONBLOCK;   /* just populate ptes */
 #endif
     }
+#if defined(_WIN32) && !defined(__CYGWIN__) && !defined(__CYGWIN32__)
+    flags |= O_BINARY;
+#endif
 
     if ((rrd_file->fd = open(file_name, flags, mode)) < 0) {
         rrd_set_error("opening '%s': %s", file_name, rrd_strerror(errno));
@@ -254,11 +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);
@@ -318,12 +358,19 @@ 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
@@ -360,18 +407,23 @@ 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
-#endif /* without madvise and posix_fadvise ist does not make much sense todo anything */
+#endif                          /* without madvise and posix_fadvise ist does not make much sense todo anything */
 }
 
 
@@ -429,7 +481,7 @@ off_t rrd_seek(
 
 /* Get current position in rrd_file.  */
 
-inline off_t rrd_tell(
+off_t rrd_tell(
     rrd_file_t *rrd_file)
 {
     return rrd_file->pos;
@@ -439,7 +491,7 @@ inline off_t rrd_tell(
 /* Read count bytes into buffer buf, starting at rrd_file->pos.
  * Returns the number of bytes read or <0 on error.  */
 
-inline ssize_t rrd_read(
+ssize_t rrd_read(
     rrd_file_t *rrd_file,
     void *buf,
     size_t count)
@@ -477,7 +529,7 @@ inline ssize_t rrd_read(
  * rrd_file->pos of rrd_file->fd.
  * Returns the number of bytes written or <0 on error.  */
 
-inline ssize_t rrd_write(
+ssize_t rrd_write(
     rrd_file_t *rrd_file,
     const void *buf,
     size_t count)
@@ -502,7 +554,7 @@ inline ssize_t rrd_write(
 
 /* flush all data pending to be written to FD.  */
 
-inline void rrd_flush(
+void rrd_flush(
     rrd_file_t *rrd_file)
 {
     if (fdatasync(rrd_file->fd) != 0) {
@@ -563,4 +615,3 @@ void rrd_freemem(
 {
     free(mem);
 }
-