launch: Ensure g->cmdline is allocated before assigning g->cmdline[0].

[libguestfs.git] / src / launch.c

diff --git a/src/launch.c b/src/launch.c
index 11d1acf..ae1e100 100644 (file)
--- a/src/launch.c
+++ b/src/launch.c
@@ -105,9 +105,9 @@ free_regexps (void)
 }
 #endif
 
-/* Add a string to the current command line. */
+/* Functions to add a string to the current command line. */
 static void
-incr_cmdline_size (guestfs_h *g)
+alloc_cmdline (guestfs_h *g)
 {
   if (g->cmdline == NULL) {
     /* g->cmdline[0] is reserved for argv[0], set in guestfs_launch. */
@@ -115,7 +115,12 @@ incr_cmdline_size (guestfs_h *g)
     g->cmdline = safe_malloc (g, sizeof (char *));
     g->cmdline[0] = NULL;
   }
+}
 
+static void
+incr_cmdline_size (guestfs_h *g)
+{
+  alloc_cmdline (g);
   g->cmdline_size++;
   g->cmdline = safe_realloc (g, g->cmdline, sizeof (char *) * g->cmdline_size);
 }
@@ -160,11 +165,7 @@ guestfs__debug_cmdline (guestfs_h *g)
   size_t i;
   char **r;
 
-  if (g->cmdline == NULL) {
-    r = safe_malloc (g, sizeof (char *) * 1);
-    r[0] = NULL;
-    return r;
-  }
+  alloc_cmdline (g);
 
   r = safe_malloc (g, sizeof (char *) * (g->cmdline_size + 1));
   r[0] = safe_strdup (g, g->qemu); /* g->cmdline[0] is always NULL */
@@ -512,6 +513,12 @@ launch_appliance (guestfs_h *g)
     /* Set up the full command line.  Do this in the subprocess so we
      * don't need to worry about cleaning up.
      */
+
+    /* Set g->cmdline[0] to the name of the qemu process.  However
+     * it is possible that no g->cmdline has been allocated yet so
+     * we must do that first.
+     */
+    alloc_cmdline (g);
     g->cmdline[0] = g->qemu;
 
     if (qemu_supports (g, "-nodefconfig"))
@@ -607,6 +614,7 @@ launch_appliance (guestfs_h *g)
     "console=ttyS0 "   /* serial console */                            \
     "udevtimeout=300 " /* good for very slow systems (RHBZ#480319) */  \
     "noapic "          /* workaround for RHBZ#502058 - ok if not SMP */ \
+    "no_timer_check "  /* fix for RHBZ#502058 */                        \
     "acpi=off "        /* we don't need ACPI, turn it off */           \
     "printk.time=1 "   /* display timestamp before kernel messages */   \
     "cgroup_disable=memory " /* saves us about 5 MB of RAM */
@@ -1083,7 +1091,8 @@ test_qemu (guestfs_h *g)
    * probably indicates that the qemu binary is missing.
    */
   if (test_qemu_cmd (g, cmd, &g->qemu_help) == -1) {
-    perrorf (g, _("%s: command failed: If qemu is located on a non-standard path, try setting the LIBGUESTFS_QEMU environment variable."), cmd);
+    error (g, _("command failed: %s\n\nIf qemu is located on a non-standard path, try setting the LIBGUESTFS_QEMU\nenvironment variable.  There may also be errors printed above."),
+           cmd);
     return -1;
   }