X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=src%2Flaunch.c;h=047a1e154df540fc03cba1b0bad1342aa40cf61d;hp=9262cc5c7db281f0dd1c3181b2a9144d67517366;hb=d600342b7d29c0176ff96a7807ebb38303ecb3a6;hpb=4963be850090933e5769f9d3412d9eb86f522b1b

diff --git a/src/launch.c b/src/launch.c
index 9262cc5..047a1e1 100644
--- a/src/launch.c
+++ b/src/launch.c
@@ -63,7 +63,6 @@
 
 #include "c-ctype.h"
 #include "glthread/lock.h"
-#include "ignore-value.h"
 
 #include "guestfs.h"
 #include "guestfs-internal.h"
@@ -133,64 +132,108 @@ guestfs__config (guestfs_h *g,
   return 0;
 }
 
-int
-guestfs__add_drive_with_if (guestfs_h *g, const char *filename,
-                            const char *drive_if)
+/* cache=off improves reliability in the event of a host crash.
+ *
+ * However this option causes qemu to try to open the file with
+ * O_DIRECT.  This fails on some filesystem types (notably tmpfs).
+ * So we check if we can open the file with or without O_DIRECT,
+ * and use cache=off (or not) accordingly.
+ */
+static int
+test_cache_off (guestfs_h *g, const char *filename)
 {
-  size_t len = strlen (filename) + 64;
-  char buf[len];
-
-  if (strchr (filename, ',') != NULL) {
-    error (g, _("filename cannot contain ',' (comma) character"));
-    return -1;
+  int fd = open (filename, O_RDONLY|O_DIRECT);
+  if (fd >= 0) {
+    close (fd);
+    return 1;
   }
 
-  /* cache=off improves reliability in the event of a host crash.
-   *
-   * However this option causes qemu to try to open the file with
-   * O_DIRECT.  This fails on some filesystem types (notably tmpfs).
-   * So we check if we can open the file with or without O_DIRECT,
-   * and use cache=off (or not) accordingly.
-   *
-   * This test also checks for the presence of the file, which
-   * is a documented semantic of this interface.
-   */
-  int fd = open (filename, O_RDONLY|O_DIRECT);
+  fd = open (filename, O_RDONLY);
   if (fd >= 0) {
     close (fd);
-    snprintf (buf, len, "file=%s,cache=off,if=%s", filename, drive_if);
-  } else {
-    fd = open (filename, O_RDONLY);
-    if (fd >= 0) {
-      close (fd);
-      snprintf (buf, len, "file=%s,if=%s", filename, drive_if);
-    } else {
-      perrorf (g, "%s", filename);
-      return -1;
-    }
+    return 0;
   }
 
-  return guestfs__config (g, "-drive", buf);
+  perrorf (g, "%s", filename);
+  return -1;
+}
+
+/* Check string parameter matches ^[-_[:alnum:]]+$ (in C locale). */
+static int
+valid_format_iface (const char *str)
+{
+  size_t len = strlen (str);
+
+  if (len == 0)
+    return 0;
+
+  while (len > 0) {
+    char c = *str++;
+    len--;
+    if (c != '-' && c != '_' && !c_isalnum (c))
+      return 0;
+  }
+  return 1;
 }
 
 int
-guestfs__add_drive_ro_with_if (guestfs_h *g, const char *filename,
-                               const char *drive_if)
+guestfs__add_drive_opts (guestfs_h *g, const char *filename,
+                         const struct guestfs_add_drive_opts_argv *optargs)
 {
+  int readonly;
+  const char *format;
+  const char *iface;
+
   if (strchr (filename, ',') != NULL) {
     error (g, _("filename cannot contain ',' (comma) character"));
     return -1;
   }
 
-  if (access (filename, F_OK) == -1) {
-    perrorf (g, "%s", filename);
+  readonly = optargs->bitmask & GUESTFS_ADD_DRIVE_OPTS_READONLY_BITMASK
+             ? optargs->readonly : 0;
+  format = optargs->bitmask & GUESTFS_ADD_DRIVE_OPTS_FORMAT_BITMASK
+           ? optargs->format : NULL;
+  iface = optargs->bitmask & GUESTFS_ADD_DRIVE_OPTS_IFACE_BITMASK
+          ? optargs->iface : DRIVE_IF;
+
+  if (format && !valid_format_iface (format)) {
+    error (g, _("%s parameter is empty or contains disallowed characters"),
+           "format");
+    return -1;
+  }
+  if (!valid_format_iface (iface)) {
+    error (g, _("%s parameter is empty or contains disallowed characters"),
+           "iface");
+    return -1;
+  }
+
+  /* For writable files, see if we can use cache=off.  This also
+   * checks for the existence of the file.  For readonly we have
+   * to do the check explicitly.
+   */
+  int use_cache_off = readonly ? 0 : test_cache_off (g, filename);
+  if (use_cache_off == -1)
     return -1;
+
+  if (readonly) {
+    if (access (filename, F_OK) == -1) {
+      perrorf (g, "%s", filename);
+      return -1;
+    }
   }
 
-  size_t len = strlen (filename) + 64;
+  /* Construct the final -drive parameter. */
+  size_t len = 64 + strlen (filename) + strlen (iface);
+  if (format) len += strlen (format);
   char buf[len];
 
-  snprintf (buf, len, "file=%s,snapshot=on,if=%s", filename, drive_if);
+  snprintf (buf, len, "file=%s%s%s%s%s,if=%s",
+            filename,
+            readonly ? ",snapshot=on" : "",
+            use_cache_off ? ",cache=off" : "",
+            format ? ",format=" : "",
+            format ? format : "",
+            iface);
 
   return guestfs__config (g, "-drive", buf);
 }
@@ -198,13 +241,48 @@ guestfs__add_drive_ro_with_if (guestfs_h *g, const char *filename,
 int
 guestfs__add_drive (guestfs_h *g, const char *filename)
 {
-  return guestfs__add_drive_with_if (g, filename, DRIVE_IF);
+  struct guestfs_add_drive_opts_argv optargs = {
+    .bitmask = 0,
+  };
+
+  return guestfs__add_drive_opts (g, filename, &optargs);
 }
 
 int
 guestfs__add_drive_ro (guestfs_h *g, const char *filename)
 {
-  return guestfs__add_drive_ro_with_if (g, filename, DRIVE_IF);
+  struct guestfs_add_drive_opts_argv optargs = {
+    .bitmask = GUESTFS_ADD_DRIVE_OPTS_READONLY_BITMASK,
+    .readonly = 1,
+  };
+
+  return guestfs__add_drive_opts (g, filename, &optargs);
+}
+
+int
+guestfs__add_drive_with_if (guestfs_h *g, const char *filename,
+                            const char *iface)
+{
+  struct guestfs_add_drive_opts_argv optargs = {
+    .bitmask = GUESTFS_ADD_DRIVE_OPTS_IFACE_BITMASK,
+    .iface = iface,
+  };
+
+  return guestfs__add_drive_opts (g, filename, &optargs);
+}
+
+int
+guestfs__add_drive_ro_with_if (guestfs_h *g, const char *filename,
+                               const char *iface)
+{
+  struct guestfs_add_drive_opts_argv optargs = {
+    .bitmask = GUESTFS_ADD_DRIVE_OPTS_IFACE_BITMASK
+             | GUESTFS_ADD_DRIVE_OPTS_READONLY_BITMASK,
+    .iface = iface,
+    .readonly = 1,
+  };
+
+  return guestfs__add_drive_opts (g, filename, &optargs);
 }
 
 int
@@ -251,10 +329,7 @@ guestfs__launch (guestfs_h *g)
 
   /* Make the temporary directory. */
   if (!g->tmpdir) {
-    const char *tmpdir = guestfs___tmpdir ();
-    char dir_template[strlen (tmpdir) + 32];
-    sprintf (dir_template, "%s/libguestfsXXXXXX", tmpdir);
-
+    TMP_TEMPLATE_ON_STACK (dir_template);
     g->tmpdir = safe_strdup (g, dir_template);
     if (mkdtemp (g->tmpdir) == NULL) {
       perrorf (g, _("%s: cannot create temporary directory"), dir_template);
@@ -342,6 +417,9 @@ guestfs__launch (guestfs_h *g)
      */
     g->cmdline[0] = g->qemu;
 
+    if (qemu_supports (g, "-nodefconfig"))
+      add_cmdline (g, "-nodefconfig");
+
     /* qemu sometimes needs this option to enable hardware
      * virtualization, but some versions of 'qemu-kvm' will use KVM
      * regardless (even where this option appears in the help text).
@@ -413,7 +491,7 @@ guestfs__launch (guestfs_h *g)
     /* Enable user networking. */
     if (g->enable_network) {
       add_cmdline (g, "-netdev");
-      add_cmdline (g, "user,id=usernet");
+      add_cmdline (g, "user,id=usernet,net=169.254.0.0/16");
       add_cmdline (g, "-device");
       add_cmdline (g, NET_IF ",netdev=usernet");
     }
@@ -510,6 +588,8 @@ guestfs__launch (guestfs_h *g)
   kernel = NULL;
   free (initrd);
   initrd = NULL;
+  free (appliance);
+  appliance = NULL;
 
   /* Fork the recovery process off which will kill qemu if the parent
    * process fails to do so (eg. if the parent segfaults).
@@ -646,8 +726,11 @@ guestfs__launch (guestfs_h *g)
   return -1;
 }
 
+/* Return the location of the tmpdir (eg. "/tmp") and allow users
+ * to override it at runtime using $TMPDIR.
+ */
 const char *
-guestfs___tmpdir (void)
+guestfs_tmpdir (void)
 {
   const char *tmpdir;
 
@@ -761,7 +844,7 @@ test_qemu (guestfs_h *g)
     goto error;
 
   snprintf (cmd, sizeof cmd, "LC_ALL=C '%s' -nographic -version 2>/dev/null",
-	    g->qemu);
+            g->qemu);
 
   fp = popen (cmd, "r");
   if (fp) {