X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=src%2Fguestfs.c;h=f79aaedf3612f86369e38ffcde6a75979a72b8d0;hp=a5b3ae42772c6690b23be0118bc4ec24ff128439;hb=2fbac04b9de826fb49400a1fc7a97262b76d078e;hpb=09c16b5da0ec982bfffe654a55abd637a3335c95

diff --git a/src/guestfs.c b/src/guestfs.c
index a5b3ae4..f79aaed 100644
--- a/src/guestfs.c
+++ b/src/guestfs.c
@@ -1,5 +1,5 @@
 /* libguestfs
- * Copyright (C) 2009 Red Hat Inc. 
+ * Copyright (C) 2009-2010 Red Hat Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -23,11 +23,20 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <inttypes.h>
 #include <unistd.h>
-#include <ctype.h>
 #include <string.h>
 #include <fcntl.h>
 #include <time.h>
+#include <sys/stat.h>
+#include <sys/select.h>
+#include <dirent.h>
+#include <assert.h>
+
+#include <rpc/types.h>
+#include <rpc/xdr.h>
 
 #ifdef HAVE_ERRNO_H
 #include <errno.h>
@@ -49,549 +58,676 @@
 #include <sys/un.h>
 #endif
 
-#include "guestfs.h"
-
-static int error (guestfs_h *g, const char *fs, ...);
-static int perrorf (guestfs_h *g, const char *fs, ...);
-static void *safe_malloc (guestfs_h *g, int nbytes);
-static void *safe_realloc (guestfs_h *g, void *ptr, int nbytes);
-static char *safe_strdup (guestfs_h *g, const char *str);
+#include <arpa/inet.h>
+#include <netinet/in.h>
 
-#define VMCHANNEL_PORT 6666
-#define VMCHANNEL_ADDR "10.0.2.4"
+#include "glthread/lock.h"
+#include "hash.h"
+#include "hash-pjw.h"
 
-/* GuestFS handle and connection. */
-struct guestfs_h
-{
-  /* All these socks/pids are -1 if not connected. */
-  int sock;			/* Daemon communications socket. */
-  int pid;			/* Qemu PID. */
-  time_t start_t;		/* The time when we started qemu. */
-  int daemon_up;		/* Received hello message from daemon. */
-
-  char *tmpdir;			/* Temporary directory containing logfile
-				 * and socket.  Cleaned up unless there is
-				 * an error.
-				 */
+#include "guestfs.h"
+#include "guestfs-internal.h"
+#include "guestfs-internal-actions.h"
+#include "guestfs_protocol.h"
 
-  char **cmdline;		/* Qemu command line. */
-  int cmdline_size;
+static void default_error_cb (guestfs_h *g, void *data, const char *msg);
+static void close_handles (void);
 
-  guestfs_abort_fn abort_fn;
-  int exit_on_error;
-  int verbose;
-};
+gl_lock_define_initialized (static, handles_lock);
+static guestfs_h *handles = NULL;
+static int atexit_handler_set = 0;
 
 guestfs_h *
 guestfs_create (void)
 {
   guestfs_h *g;
+  const char *str;
 
   g = malloc (sizeof (*g));
   if (!g) return NULL;
 
+  memset (g, 0, sizeof (*g));
+
+  g->state = CONFIG;
+
+  g->fd[0] = -1;
+  g->fd[1] = -1;
   g->sock = -1;
-  g->pid = -1;
 
-  g->start_t = 0;
-  g->daemon_up = 0;
+  g->abort_cb = abort;
+  g->error_cb = default_error_cb;
+  g->error_cb_data = NULL;
+
+  g->recovery_proc = 1;
 
-  g->tmpdir = NULL;
+  str = getenv ("LIBGUESTFS_DEBUG");
+  g->verbose = str != NULL && STREQ (str, "1");
 
-  g->abort_fn = abort;		/* Have to set these before safe_malloc. */
-  g->exit_on_error = 0;
-  g->verbose = getenv ("LIBGUESTFS_VERBOSE") != NULL;
+  str = getenv ("LIBGUESTFS_TRACE");
+  g->trace = str != NULL && STREQ (str, "1");
 
-  g->cmdline = safe_malloc (g, sizeof (char *) * 1);
-  g->cmdline_size = 1;
-  g->cmdline[0] = NULL;		/* This is chosen by guestfs_launch. */
+  str = getenv ("LIBGUESTFS_PATH");
+  g->path = str != NULL ? strdup (str) : strdup (GUESTFS_DEFAULT_PATH);
+  if (!g->path) goto error;
+
+  str = getenv ("LIBGUESTFS_QEMU");
+  g->qemu = str != NULL ? strdup (str) : strdup (QEMU);
+  if (!g->qemu) goto error;
+
+  str = getenv ("LIBGUESTFS_APPEND");
+  if (str) {
+    g->append = strdup (str);
+    if (!g->append) goto error;
+  }
+
+  /* Choose a suitable memory size.  Previously we tried to choose
+   * a minimal memory size, but this isn't really necessary since
+   * recent QEMU and KVM don't do anything nasty like locking
+   * memory into core any more.  Thus we can safely choose a
+   * large, generous amount of memory, and it'll just get swapped
+   * on smaller systems.
+   */
+  str = getenv ("LIBGUESTFS_MEMSIZE");
+  if (str) {
+    if (sscanf (str, "%d", &g->memsize) != 1 || g->memsize <= 256) {
+      fprintf (stderr, "libguestfs: non-numeric or too small value for LIBGUESTFS_MEMSIZE\n");
+      goto error;
+    }
+  } else
+    g->memsize = 500;
+
+  /* Start with large serial numbers so they are easy to spot
+   * inside the protocol.
+   */
+  g->msg_next_serial = 0x00123400;
+
+  /* Link the handles onto a global list. */
+  gl_lock_lock (handles_lock);
+  g->next = handles;
+  handles = g;
+  if (!atexit_handler_set) {
+    atexit (close_handles);
+    atexit_handler_set = 1;
+  }
+  gl_lock_unlock (handles_lock);
+
+  if (g->verbose)
+    fprintf (stderr, "new guestfs handle %p\n", g);
 
   return g;
+
+ error:
+  free (g->path);
+  free (g->qemu);
+  free (g->append);
+  free (g);
+  return NULL;
 }
 
 void
-guestfs_free (guestfs_h *g)
+guestfs_close (guestfs_h *g)
 {
   int i;
   char filename[256];
+  guestfs_h *gg;
+
+  if (g->state == NO_HANDLE) {
+    /* Not safe to call 'error' here, so ... */
+    fprintf (stderr, _("guestfs_close: called twice on the same handle\n"));
+    return;
+  }
+
+  if (g->verbose)
+    fprintf (stderr, "closing guestfs handle %p (state %d)\n", g, g->state);
 
-  if (g->pid) guestfs_kill_subprocess (g);
+  /* Run user close callback before anything else. */
+  if (g->close_cb)
+    g->close_cb (g, g->close_cb_data);
 
-  /* The assumption is that programs calling this have successfully
-   * used qemu, so delete the logfile and socket directory.
+  guestfs___free_inspect_info (g);
+
+  /* Try to sync if autosync flag is set. */
+  if (g->autosync && g->state == READY) {
+    guestfs_umount_all (g);
+    guestfs_sync (g);
+  }
+
+  /* Remove any handlers that might be called back before we kill the
+   * subprocess.
    */
+  g->log_message_cb = NULL;
+
+  if (g->state != CONFIG)
+    guestfs_kill_subprocess (g);
+
+  /* Close sockets. */
+  if (g->fd[0] >= 0)
+    close (g->fd[0]);
+  if (g->fd[1] >= 0)
+    close (g->fd[1]);
+  if (g->sock >= 0)
+    close (g->sock);
+  g->fd[0] = -1;
+  g->fd[1] = -1;
+  g->sock = -1;
+
+  /* Wait for subprocess(es) to exit. */
+  waitpid (g->pid, NULL, 0);
+  if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0);
+
+  /* Remove tmpfiles. */
   if (g->tmpdir) {
     snprintf (filename, sizeof filename, "%s/sock", g->tmpdir);
     unlink (filename);
 
-    snprintf (filename, sizeof filename, "%s/qemu.log", g->tmpdir);
-    unlink (filename);
-
     rmdir (g->tmpdir);
 
     free (g->tmpdir);
   }
 
-  for (i = 0; i < g->cmdline_size; ++i)
-    free (g->cmdline[i]);
-  free (g->cmdline);
+  if (g->cmdline) {
+    for (i = 0; i < g->cmdline_size; ++i)
+      free (g->cmdline[i]);
+    free (g->cmdline);
+  }
+
+  /* Mark the handle as dead before freeing it. */
+  g->state = NO_HANDLE;
 
+  gl_lock_lock (handles_lock);
+  if (handles == g)
+    handles = g->next;
+  else {
+    for (gg = handles; gg->next != g; gg = gg->next)
+      ;
+    gg->next = g->next;
+  }
+  gl_lock_unlock (handles_lock);
+
+  if (g->pda)
+    hash_free (g->pda);
+  free (g->last_error);
+  free (g->path);
+  free (g->qemu);
+  free (g->append);
+  free (g->qemu_help);
+  free (g->qemu_version);
   free (g);
 }
 
-/* Cleanup fds and sockets, assuming the subprocess is dead already. */
+/* Close all open handles (called from atexit(3)). */
 static void
-cleanup_fds (guestfs_h *g)
+close_handles (void)
 {
-  if (g->sock >= 0) close (g->sock);
-  g->sock = -1;
+  while (handles) guestfs_close (handles);
+}
+
+const char *
+guestfs_last_error (guestfs_h *g)
+{
+  return g->last_error;
+}
+
+static void
+set_last_error (guestfs_h *g, const char *msg)
+{
+  free (g->last_error);
+  g->last_error = strdup (msg);
 }
 
-/* Wait for subprocess to exit. */
 static void
-wait_subprocess (guestfs_h *g)
+default_error_cb (guestfs_h *g, void *data, const char *msg)
 {
-  if (g->pid >= 0) waitpid (g->pid, NULL, 0);
-  g->pid = -1;
+  fprintf (stderr, _("libguestfs: error: %s\n"), msg);
 }
 
-static int
-error (guestfs_h *g, const char *fs, ...)
+void
+guestfs_error (guestfs_h *g, const char *fs, ...)
 {
   va_list args;
+  char *msg;
 
-  fprintf (stderr, "libguestfs: ");
   va_start (args, fs);
-  vfprintf (stderr, fs, args);
+  int err = vasprintf (&msg, fs, args);
   va_end (args);
-  fputc ('\n', stderr);
 
-  if (g->exit_on_error) {
-    guestfs_kill_subprocess (g);
-    exit (1);
-  }
-  return -1;
+  if (err < 0) return;
+
+  if (g->error_cb) g->error_cb (g, g->error_cb_data, msg);
+  set_last_error (g, msg);
+
+  free (msg);
 }
 
-static int
-perrorf (guestfs_h *g, const char *fs, ...)
+void
+guestfs_perrorf (guestfs_h *g, const char *fs, ...)
 {
   va_list args;
-  char buf[256];
-  int err = errno;
+  char *msg;
+  int errnum = errno;
 
-  fprintf (stderr, "libguestfs: ");
   va_start (args, fs);
-  vfprintf (stderr, fs, args);
+  int err = vasprintf (&msg, fs, args);
   va_end (args);
-  strerror_r (err, buf, sizeof buf);
-  fprintf (stderr, ": %s\n", buf);
 
-  if (g->exit_on_error) {
-    guestfs_kill_subprocess (g);
-    exit (1);
-  }
-  return -1;
+  if (err < 0) return;
+
+#if !defined(_GNU_SOURCE) || defined(__APPLE__)
+  char buf[256];
+  strerror_r (errnum, buf, sizeof buf);
+#else
+  char _buf[256];
+  char *buf;
+  buf = strerror_r (errnum, _buf, sizeof _buf);
+#endif
+
+  msg = safe_realloc (g, msg, strlen (msg) + 2 + strlen (buf) + 1);
+  strcat (msg, ": ");
+  strcat (msg, buf);
+
+  if (g->error_cb) g->error_cb (g, g->error_cb_data, msg);
+  set_last_error (g, msg);
+
+  free (msg);
 }
 
-static void *
-safe_malloc (guestfs_h *g, int nbytes)
+void *
+guestfs_safe_malloc (guestfs_h *g, size_t nbytes)
 {
   void *ptr = malloc (nbytes);
-  if (!ptr) g->abort_fn ();
+  if (nbytes > 0 && !ptr) g->abort_cb ();
   return ptr;
 }
 
-static void *
-safe_realloc (guestfs_h *g, void *ptr, int nbytes)
+/* Return 1 if an array of N objects, each of size S, cannot exist due
+   to size arithmetic overflow.  S must be positive and N must be
+   nonnegative.  This is a macro, not an inline function, so that it
+   works correctly even when SIZE_MAX < N.
+
+   By gnulib convention, SIZE_MAX represents overflow in size
+   calculations, so the conservative dividend to use here is
+   SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
+   However, malloc (SIZE_MAX) fails on all known hosts where
+   sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
+   exactly-SIZE_MAX allocations on such hosts; this avoids a test and
+   branch when S is known to be 1.  */
+# define xalloc_oversized(n, s) \
+    ((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
+
+/* Technically we should add an autoconf test for this, testing for the desired
+   functionality, like what's done in gnulib, but for now, this is fine.  */
+#if defined(__GLIBC__)
+#define HAVE_GNU_CALLOC (__GLIBC__ >= 2)
+#else
+#define HAVE_GNU_CALLOC 0
+#endif
+
+/* Allocate zeroed memory for N elements of S bytes, with error
+   checking.  S must be nonzero.  */
+void *
+guestfs_safe_calloc (guestfs_h *g, size_t n, size_t s)
+{
+  /* From gnulib's calloc function in xmalloc.c.  */
+  void *p;
+  /* Test for overflow, since some calloc implementations don't have
+     proper overflow checks.  But omit overflow and size-zero tests if
+     HAVE_GNU_CALLOC, since GNU calloc catches overflow and never
+     returns NULL if successful.  */
+  if ((! HAVE_GNU_CALLOC && xalloc_oversized (n, s))
+      || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0)))
+    g->abort_cb ();
+  return p;
+}
+
+void *
+guestfs_safe_realloc (guestfs_h *g, void *ptr, int nbytes)
 {
   void *p = realloc (ptr, nbytes);
-  if (!p) g->abort_fn ();
+  if (nbytes > 0 && !p) g->abort_cb ();
   return p;
 }
 
-static char *
-safe_strdup (guestfs_h *g, const char *str)
+char *
+guestfs_safe_strdup (guestfs_h *g, const char *str)
 {
   char *s = strdup (str);
-  if (!s) g->abort_fn ();
+  if (!s) g->abort_cb ();
+  return s;
+}
+
+char *
+guestfs_safe_strndup (guestfs_h *g, const char *str, size_t n)
+{
+  char *s = strndup (str, n);
+  if (!s) g->abort_cb ();
   return s;
 }
 
+void *
+guestfs_safe_memdup (guestfs_h *g, void *ptr, size_t size)
+{
+  void *p = malloc (size);
+  if (!p) g->abort_cb ();
+  memcpy (p, ptr, size);
+  return p;
+}
+
 void
-guestfs_set_out_of_memory_handler (guestfs_h *g, guestfs_abort_fn a)
+guestfs_set_out_of_memory_handler (guestfs_h *g, guestfs_abort_cb cb)
 {
-  g->abort_fn = a;
+  g->abort_cb = cb;
 }
 
-guestfs_abort_fn
+guestfs_abort_cb
 guestfs_get_out_of_memory_handler (guestfs_h *g)
 {
-  return g->abort_fn;
+  return g->abort_cb;
 }
 
 void
-guestfs_set_exit_on_error (guestfs_h *g, int e)
+guestfs_set_error_handler (guestfs_h *g, guestfs_error_handler_cb cb, void *data)
 {
-  g->exit_on_error = e;
+  g->error_cb = cb;
+  g->error_cb_data = data;
 }
 
-int
-guestfs_get_exit_on_error (guestfs_h *g)
+guestfs_error_handler_cb
+guestfs_get_error_handler (guestfs_h *g, void **data_rtn)
 {
-  return g->exit_on_error;
+  if (data_rtn) *data_rtn = g->error_cb_data;
+  return g->error_cb;
 }
 
-void
-guestfs_set_verbose (guestfs_h *g, int v)
+int
+guestfs__set_verbose (guestfs_h *g, int v)
 {
-  g->verbose = v;
+  g->verbose = !!v;
+  return 0;
 }
 
 int
-guestfs_get_verbose (guestfs_h *g)
+guestfs__get_verbose (guestfs_h *g)
 {
   return g->verbose;
 }
 
-/* Add an escaped string to the current command line. */
-static int
-add_cmdline (guestfs_h *g, const char *str)
+int
+guestfs__set_autosync (guestfs_h *g, int a)
 {
-  if (g->pid >= 0)
-    return error (g, "command line cannot be altered after qemu subprocess launched");
-
-  g->cmdline_size++;
-  g->cmdline = safe_realloc (g, g->cmdline, sizeof (char *) * g->cmdline_size);
-  g->cmdline[g->cmdline_size-1] = safe_strdup (g, str);
-
+  g->autosync = !!a;
   return 0;
 }
 
 int
-guestfs_config (guestfs_h *g,
-		const char *qemu_param, const char *qemu_value)
+guestfs__get_autosync (guestfs_h *g)
 {
-  if (qemu_param[0] != '-')
-    return error (g, "guestfs_config: parameter must begin with '-' character");
+  return g->autosync;
+}
 
-  /* A bit fascist, but the user will probably break the extra
-   * parameters that we add if they try to set any of these.
-   */
-  if (strcmp (qemu_param, "-kernel") == 0 ||
-      strcmp (qemu_param, "-initrd") == 0 ||
-      strcmp (qemu_param, "-nographic") == 0 ||
-      strcmp (qemu_param, "-serial") == 0 ||
-      strcmp (qemu_param, "-vnc") == 0 ||
-      strcmp (qemu_param, "-full-screen") == 0 ||
-      strcmp (qemu_param, "-std-vga") == 0 ||
-      strcmp (qemu_param, "-vnc") == 0)
-    return error (g, "guestfs_config: parameter '%s' isn't allowed");
-
-  if (add_cmdline (g, qemu_param) != 0) return -1;
-
-  if (qemu_value != NULL) {
-    if (add_cmdline (g, qemu_value) != 0) return -1;
-  }
+int
+guestfs__set_path (guestfs_h *g, const char *path)
+{
+  free (g->path);
+  g->path = NULL;
 
+  g->path =
+    path == NULL ?
+    safe_strdup (g, GUESTFS_DEFAULT_PATH) : safe_strdup (g, path);
   return 0;
 }
 
-int
-guestfs_add_drive (guestfs_h *g, const char *filename)
+const char *
+guestfs__get_path (guestfs_h *g)
 {
-  int len = strlen (filename) + 64;
-  char buf[len];
+  return g->path;
+}
 
-  if (strchr (filename, ',') != NULL)
-    return error (g, "filename cannot contain ',' (comma) character");
+int
+guestfs__set_qemu (guestfs_h *g, const char *qemu)
+{
+  free (g->qemu);
+  g->qemu = NULL;
 
-  snprintf (buf, len, "file=%s,media=disk", filename);
+  g->qemu = qemu == NULL ? safe_strdup (g, QEMU) : safe_strdup (g, qemu);
+  return 0;
+}
 
-  return guestfs_config (g, "-drive", buf);
+const char *
+guestfs__get_qemu (guestfs_h *g)
+{
+  return g->qemu;
 }
 
 int
-guestfs_add_cdrom (guestfs_h *g, const char *filename)
+guestfs__set_append (guestfs_h *g, const char *append)
 {
-  int len = strlen (filename) + 64;
-  char buf[len];
-
-  if (strchr (filename, ',') != NULL)
-    return error (g, "filename cannot contain ',' (comma) character");
+  free (g->append);
+  g->append = NULL;
 
-  snprintf (buf, len, "file=%s,if=ide,index=1,media=cdrom", filename);
+  g->append = append ? safe_strdup (g, append) : NULL;
+  return 0;
+}
 
-  return guestfs_config (g, "-drive", buf);
+const char *
+guestfs__get_append (guestfs_h *g)
+{
+  return g->append;
 }
 
 int
-guestfs_launch (guestfs_h *g)
-{
-  static const char *dir_template = "/tmp/libguestfsXXXXXX";
-  int r, i;
-  /*const char *qemu = QEMU;*/	/* XXX */
-  const char *qemu = "/home/rjones/d/redhat/libguestfs/qemu";
-  const char *kernel = "/boot/vmlinuz-2.6.27.15-170.2.24.fc10.x86_64";
-  const char *initrd = "/tmp/initrd-2.6.27.15-170.2.24.fc10.x86_64.img";
-  char unixsock[256];
-
-  /* XXX Choose which qemu to run. */
-  /* XXX Choose initrd, etc. */
-
-  /* Make the temporary directory containing the logfile and socket. */
-  if (!g->tmpdir) {
-    g->tmpdir = safe_strdup (g, dir_template);
-    if (mkdtemp (g->tmpdir) == NULL)
-      return perrorf (g, "%s: cannot create temporary directory", dir_template);
-
-    snprintf (unixsock, sizeof unixsock, "%s/sock", g->tmpdir);
-  }
+guestfs__set_memsize (guestfs_h *g, int memsize)
+{
+  g->memsize = memsize;
+  return 0;
+}
 
-  r = fork ();
-  if (r == -1)
-    return perrorf (g, "fork");
+int
+guestfs__get_memsize (guestfs_h *g)
+{
+  return g->memsize;
+}
 
-  if (r > 0) {			/* Parent (library). */
-    g->pid = r;
+int
+guestfs__set_selinux (guestfs_h *g, int selinux)
+{
+  g->selinux = selinux;
+  return 0;
+}
 
-    /* If qemu is going to die during startup, give it a tiny amount
-     * of time to print the error message.
-     */
-    usleep (10000);
+int
+guestfs__get_selinux (guestfs_h *g)
+{
+  return g->selinux;
+}
 
-    /* Start the clock ... */
-    time (&g->start_t);
+int
+guestfs__get_pid (guestfs_h *g)
+{
+  if (g->pid > 0)
+    return g->pid;
+  else {
+    error (g, "get_pid: no qemu subprocess");
+    return -1;
   }
-  else {			/* Child (qemu). */
-    char vmchannel[256];
-    char logfile[256];
-    char append[256];
-
-    /* Set up the full command line.  Do this in the subprocess so we
-     * don't need to worry about cleaning up.
-     */
-    g->cmdline[0] = (char *) qemu;
-
-    g->cmdline =
-      realloc (g->cmdline, sizeof (char *) * (g->cmdline_size + 16));
-    if (g->cmdline == NULL) {
-      perror ("realloc");
-      _exit (1);
-    }
-
-    /* Construct the -net channel parameter for qemu. */
-    snprintf (vmchannel, sizeof vmchannel,
-	      "channel,%d:unix:%s,server,nowait", VMCHANNEL_PORT, unixsock);
-
-    /* Linux kernel command line. */
-    snprintf (append, sizeof append,
-	      "console=ttyS0 guestfs=%s:%d", VMCHANNEL_ADDR, VMCHANNEL_PORT);
-
-    /* XXX -m */
-
-    g->cmdline[g->cmdline_size   ] = "-kernel";
-    g->cmdline[g->cmdline_size+ 1] = (char *) kernel;
-    g->cmdline[g->cmdline_size+ 2] = "-initrd";
-    g->cmdline[g->cmdline_size+ 3] = (char *) initrd;
-    g->cmdline[g->cmdline_size+ 4] = "-append";
-    g->cmdline[g->cmdline_size+ 5] = append;
-    g->cmdline[g->cmdline_size+ 6] = "-nographic";
-    g->cmdline[g->cmdline_size+ 7] = "-serial";
-    g->cmdline[g->cmdline_size+ 8] = "stdio";
-    g->cmdline[g->cmdline_size+ 9] = "-net";
-    g->cmdline[g->cmdline_size+10] = vmchannel;
-    g->cmdline[g->cmdline_size+11] = "-net";
-    g->cmdline[g->cmdline_size+12] = "user,vlan=0";
-    g->cmdline[g->cmdline_size+13] = "-net";
-    g->cmdline[g->cmdline_size+14] = "nic,vlan=0";
-    g->cmdline[g->cmdline_size+15] = NULL;
-
-    if (g->verbose) {
-      fprintf (stderr, "Running %s", qemu);
-      for (i = 0; g->cmdline[i]; ++i)
-	fprintf (stderr, " %s", g->cmdline[i]);
-      fprintf (stderr, "\n");
-    }
+}
 
-    /* Set up stdin, stdout.  Messages should go to the logfile. */
-    close (0);
-    close (1);
-    open ("/dev/null", O_RDONLY);
-    snprintf (logfile, sizeof logfile, "%s/qemu.log", g->tmpdir);
-    open (logfile, O_WRONLY|O_CREAT|O_APPEND, 0644);
-    /*dup2 (1, 2);*/
-
-    /* Set up a new process group, so we can signal this process
-     * and all subprocesses (eg. if qemu is really a shell script).
-     */
-    setpgid (0, 0);
-
-    execv (qemu, g->cmdline);	/* Run qemu. */
-    perror (qemu);
-    _exit (1);
-  }
+struct guestfs_version *
+guestfs__version (guestfs_h *g)
+{
+  struct guestfs_version *r;
+
+  r = safe_malloc (g, sizeof *r);
+  r->major = PACKAGE_VERSION_MAJOR;
+  r->minor = PACKAGE_VERSION_MINOR;
+  r->release = PACKAGE_VERSION_RELEASE;
+  r->extra = safe_strdup (g, PACKAGE_VERSION_EXTRA);
+  return r;
+}
 
+int
+guestfs__set_trace (guestfs_h *g, int t)
+{
+  g->trace = !!t;
   return 0;
 }
 
-/* A peculiarity of qemu's vmchannel implementation is that both sides
- * connect to qemu, ie:
- *
- *   libguestfs  --- connect --> qemu <-- connect --- daemon
- *    (host)                                          (guest)
- *
- * This has several implications: (1) qemu creates the Unix socket, so
- * we have to wait for it to do that.  (2) we have to arrange for the
- * daemon to send a "hello" message which we also wait for.
- *
- * At any time during this, the qemu subprocess might run slowly, die
- * or hang (it's very prone to just hanging if the BIOS fails for any
- * reason or if the kernel cannot be found to boot from).
- *
- * The only realistic way to handle this is, unfortunately, using
- * timeouts, also checking if the qemu subprocess is still alive.
- *
- * We could do better here by monitoring the Linux kernel log messages
- * (via the serial console, which is currently just redirected to a
- * log file) and seeing if the Linux guest is making progress. (XXX)
- */
-
-#define QEMU_SOCKET_TIMEOUT 5	/* How long we wait for qemu to make
-				 * the socket.  This should be very quick.
-				 */
-#define DAEMON_TIMEOUT 60	/* How long we wait for guest to boot
-				 * and start the daemon.  This could take
-				 * a potentially long time, and is very
-				 * sensitive to the overall load on the host.
-				 */
+int
+guestfs__get_trace (guestfs_h *g)
+{
+  return g->trace;
+}
 
-static int wait_ready (guestfs_h *g);
+int
+guestfs__set_direct (guestfs_h *g, int d)
+{
+  g->direct = !!d;
+  return 0;
+}
 
 int
-guestfs_wait_ready (guestfs_h *g)
+guestfs__get_direct (guestfs_h *g)
 {
-  int r;
+  return g->direct;
+}
 
-  /* Launch the subprocess, if there isn't one already. */
-  if (g->pid == -1) {
-    if (guestfs_launch (g) != 0)
-      return -1;
-  }
+int
+guestfs__set_recovery_proc (guestfs_h *g, int f)
+{
+  g->recovery_proc = !!f;
+  return 0;
+}
 
-  for (;;) {
-    r = wait_ready (g);
-    if (r == -1) {		/* Error. */
-      guestfs_kill_subprocess (g);
-      return -1;
-    }
-    else if (r > 0) {		/* Keep waiting. */
-      sleep (1);
-      continue;
-    }
-    else if (r == 0)		/* Daemon is ready. */
-      break;
-  }
+int
+guestfs__get_recovery_proc (guestfs_h *g)
+{
+  return g->recovery_proc;
+}
 
+int
+guestfs__set_network (guestfs_h *g, int v)
+{
+  g->enable_network = !!v;
   return 0;
 }
 
-#define UNIX_PATH_MAX 108
+int
+guestfs__get_network (guestfs_h *g)
+{
+  return g->enable_network;
+}
 
-/* This function is called repeatedly until the qemu subprocess and
- * daemon is ready.  It returns:
- *   -1 : error
- *    0 : done, daemon is ready
- *   >0 : not ready, keep waiting
- */
-static int
-wait_ready (guestfs_h *g)
+void
+guestfs_set_log_message_callback (guestfs_h *g,
+                                  guestfs_log_message_cb cb, void *opaque)
 {
-  int r, i, sock;
-  time_t now;
-  double elapsed;
-  struct sockaddr_un addr;
-  unsigned char m;
+  g->log_message_cb = cb;
+  g->log_message_cb_data = opaque;
+}
 
-  if (g->pid == -1) abort ();	/* Internal state error. */
+void
+guestfs_set_subprocess_quit_callback (guestfs_h *g,
+                                      guestfs_subprocess_quit_cb cb, void *opaque)
+{
+  g->subprocess_quit_cb = cb;
+  g->subprocess_quit_cb_data = opaque;
+}
 
-  /* Check the daemon is still around. */
-  r = waitpid (g->pid, NULL, WNOHANG);
+void
+guestfs_set_launch_done_callback (guestfs_h *g,
+                                  guestfs_launch_done_cb cb, void *opaque)
+{
+  g->launch_done_cb = cb;
+  g->launch_done_cb_data = opaque;
+}
 
-  if (r > 0 || (r == -1 && errno == ECHILD)) {
-    g->pid = -1;
-    return error (g,
-		  "qemu subprocess exited unexpectedly during initialization");
-  }
+void
+guestfs_set_close_callback (guestfs_h *g,
+                            guestfs_close_cb cb, void *opaque)
+{
+  g->close_cb = cb;
+  g->close_cb_data = opaque;
+}
 
-  time (&now);
-  elapsed = difftime (now, g->start_t);
-
-  if (g->sock == -1) {
-    /* Create the socket. */
-    sock = socket (AF_UNIX, SOCK_STREAM, 0);
-    if (sock == -1)
-      return perrorf (g, "socket");
-
-    addr.sun_family = AF_UNIX;
-    snprintf (addr.sun_path, UNIX_PATH_MAX, "%s/sock", g->tmpdir);
-
-    if (connect (sock, (struct sockaddr *) &addr, sizeof addr) == -1) {
-      if (elapsed <= QEMU_SOCKET_TIMEOUT) {
-	close (sock);
-	return 1;		/* Keep waiting for the socket ... */
-      }
-      perrorf (g, "qemu process hanging before making vmchannel socket");
-      close (sock);
-      return -1;
-    }
+void
+guestfs_set_progress_callback (guestfs_h *g,
+                               guestfs_progress_cb cb, void *opaque)
+{
+  g->progress_cb = cb;
+  g->progress_cb_data = opaque;
+}
 
-    if (fcntl (sock, F_SETFL, O_NONBLOCK) == -1) {
-      perrorf (g, "set socket non-blocking");
-      close (sock);
-      return -1;
-    }
+/* Note the private data area is allocated lazily, since the vast
+ * majority of callers will never use it.  This means g->pda is
+ * likely to be NULL.
+ */
+struct pda_entry {
+  char *key;                    /* key */
+  void *data;                   /* opaque user data pointer */
+};
 
-    g->sock = sock;
-  }
+static size_t
+hasher (void const *x, size_t table_size)
+{
+  struct pda_entry const *p = x;
+  return hash_pjw (p->key, table_size);
+}
 
-  if (!g->daemon_up) {
-    /* Wait for the daemon to say hello. */
-    errno = 0;
-    r = read (g->sock, &m, 1);
-    if (r == 1) {
-      if (m == 0xF5) {
-	g->daemon_up = 1;
-	return 0;
-      } else {
-	error (g, "unexpected message from qemu vmchannel or daemon");
-	return -1;
-      }
-    }
-    if (errno == EAGAIN) {
-      if (elapsed <= DAEMON_TIMEOUT)
-	return 1;		/* Keep waiting for the daemon ... */
-      error (g, "timeout waiting for guest to become ready");
-      return -1;
-    }
+static bool
+comparator (void const *x, void const *y)
+{
+  struct pda_entry const *a = x;
+  struct pda_entry const *b = y;
+  return STREQ (a->key, b->key);
+}
 
-    perrorf (g, "read");
-    return -1;
+static void
+freer (void *x)
+{
+  if (x) {
+    struct pda_entry *p = x;
+    free (p->key);
+    free (p);
   }
-
-  return 0;
 }
 
 void
-guestfs_kill_subprocess (guestfs_h *g)
+guestfs_set_private (guestfs_h *g, const char *key, void *data)
 {
-  if (g->pid >= 0) {
-    if (g->verbose)
-      fprintf (stderr, "sending SIGTERM to pgid %d\n", g->pid);
-
-    kill (- g->pid, SIGTERM);
-    wait_subprocess (g);
+  if (g->pda == NULL) {
+    g->pda = hash_initialize (16, NULL, hasher, comparator, freer);
+    if (g->pda == NULL)
+      g->abort_cb ();
   }
 
-  cleanup_fds (g);
+  struct pda_entry *new_entry = safe_malloc (g, sizeof *new_entry);
+  new_entry->key = safe_strdup (g, key);
+  new_entry->data = data;
+
+  struct pda_entry *old_entry = hash_delete (g->pda, new_entry);
+  freer (old_entry);
+
+  struct pda_entry *entry = hash_insert (g->pda, new_entry);
+  if (entry == NULL)
+    g->abort_cb ();
+  assert (entry == new_entry);
+}
+
+static inline char *
+bad_cast (char const *s)
+{
+  return (char *) s;
+}
+
+void *
+guestfs_get_private (guestfs_h *g, const char *key)
+{
+  if (g->pda == NULL)
+    return NULL;                /* no keys have been set */
+
+  const struct pda_entry k = { .key = bad_cast (key) };
+  struct pda_entry *entry = hash_lookup (g->pda, &k);
+  if (entry)
+    return entry->data;
+  else
+    return NULL;
 }