inspect: Refuse to download software hive if it is huge.

[libguestfs.git] / daemon / zero.c

diff --git a/daemon/zero.c b/daemon/zero.c
index 9d793e1..8fbd963 100644 (file)
--- a/daemon/zero.c
+++ b/daemon/zero.c
@@ -1,5 +1,5 @@
 /* libguestfs - the guestfsd daemon
- * Copyright (C) 2009 Red Hat Inc. 
+ * Copyright (C) 2009 Red Hat Inc.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -20,6 +20,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <inttypes.h>
 #include <string.h>
 #include <fcntl.h>
 #include <unistd.h>
@@ -28,13 +29,11 @@
 #include "actions.h"
 
 int
-do_zero (char *device)
+do_zero (const char *device)
 {
   int fd, i;
   char buf[4096];
 
-  IS_DEVICE (device, -1);
-
   fd = open (device, O_WRONLY);
   if (fd == -1) {
     reply_with_perror ("%s", device);
@@ -43,10 +42,66 @@ do_zero (char *device)
 
   memset (buf, 0, sizeof buf);
 
-  for (i = 0; i < 32; ++i)
-    (void) write (fd, buf, sizeof buf);
+  for (i = 0; i < 32; ++i) {
+    if (write (fd, buf, sizeof buf) != sizeof buf) {
+      reply_with_perror ("write: %s", device);
+      close (fd);
+      return -1;
+    }
+    notify_progress ((uint64_t) i, 32);
+  }
+
+  if (close (fd) == -1) {
+    reply_with_perror ("close: %s", device);
+    return -1;
+  }
+
+  return 0;
+}
+
+int
+do_zero_device (const char *device)
+{
+  int64_t ssize = do_blockdev_getsize64 (device);
+  if (ssize == -1)
+    return -1;
+  uint64_t size = (uint64_t) ssize;
+
+  int fd = open (device, O_WRONLY);
+  if (fd == -1) {
+    reply_with_perror ("%s", device);
+    return -1;
+  }
+
+  char buf[1024*1024];
+  memset (buf, 0, sizeof buf);
+
+  uint64_t pos = 0;
 
-  close (fd);
+  while (pos < size) {
+    uint64_t n64 = size - pos;
+    size_t n;
+    if (n64 > sizeof buf)
+      n = sizeof buf;
+    else
+      n = (size_t) n64; /* safe because of if condition */
+
+    ssize_t r = write (fd, buf, n);
+    if (r == -1) {
+      reply_with_perror ("write: %s (with %" PRId64 " bytes left to write)",
+                         device, size);
+      close (fd);
+      return -1;
+    }
+
+    pos += r;
+    notify_progress (pos, size);
+  }
+
+  if (close (fd) == -1) {
+    reply_with_perror ("close: %s", device);
+    return -1;
+  }
 
   return 0;
 }