2 * Copyright (C) 2009 Red Hat Inc.
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 #define _BSD_SOURCE /* for mkdtemp, usleep */
33 #include <sys/select.h>
36 #include <rpc/types.h>
43 #ifdef HAVE_SYS_TYPES_H
44 #include <sys/types.h>
47 #ifdef HAVE_SYS_WAIT_H
51 #ifdef HAVE_SYS_SOCKET_H
52 #include <sys/socket.h>
60 #include "guestfs-internal-actions.h"
61 #include "guestfs_protocol.h"
62 #include "ignore-value.h"
66 #define _(str) dgettext(PACKAGE, (str))
67 //#define N_(str) dgettext(PACKAGE, (str))
73 #define error guestfs_error
74 #define perrorf guestfs_perrorf
75 #define safe_malloc guestfs_safe_malloc
76 #define safe_realloc guestfs_safe_realloc
77 #define safe_strdup guestfs_safe_strdup
78 //#define safe_memdup guestfs_safe_memdup
80 static void default_error_cb (guestfs_h *g, void *data, const char *msg);
81 static int send_to_daemon (guestfs_h *g, const void *v_buf, size_t n);
82 static int recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn);
83 static void close_handles (void);
85 #define UNIX_PATH_MAX 108
87 /* Also in guestfsd.c */
88 #define GUESTFWD_PORT 6666
89 #define GUESTFWD_ADDR "10.0.2.4"
91 /* GuestFS handle and connection. */
92 enum state { CONFIG, LAUNCHING, READY, BUSY, NO_HANDLE };
96 struct guestfs_h *next; /* Linked list of open handles. */
98 /* State: see the state machine diagram in the man page guestfs(3). */
101 int fd[2]; /* Stdin/stdout of qemu. */
102 int sock; /* Daemon communications socket. */
103 pid_t pid; /* Qemu PID. */
104 pid_t recoverypid; /* Recovery process PID. */
105 time_t start_t; /* The time when we started qemu. */
107 char *tmpdir; /* Temporary directory containing socket. */
109 char *qemu_help, *qemu_version; /* Output of qemu -help, qemu -version. */
111 char **cmdline; /* Qemu command line. */
118 char *path; /* Path to kernel, initrd. */
119 char *qemu; /* Qemu binary. */
120 char *append; /* Append to kernel command line. */
122 int memsize; /* Size of RAM (megabytes). */
124 int selinux; /* selinux enabled? */
129 guestfs_abort_cb abort_cb;
130 guestfs_error_handler_cb error_cb;
131 void * error_cb_data;
132 guestfs_log_message_cb log_message_cb;
133 void * log_message_cb_data;
134 guestfs_subprocess_quit_cb subprocess_quit_cb;
135 void * subprocess_quit_cb_data;
136 guestfs_launch_done_cb launch_done_cb;
137 void * launch_done_cb_data;
142 static guestfs_h *handles = NULL;
143 static int atexit_handler_set = 0;
146 guestfs_create (void)
151 g = malloc (sizeof (*g));
154 memset (g, 0, sizeof (*g));
163 g->error_cb = default_error_cb;
164 g->error_cb_data = NULL;
166 str = getenv ("LIBGUESTFS_DEBUG");
167 g->verbose = str != NULL && strcmp (str, "1") == 0;
169 str = getenv ("LIBGUESTFS_TRACE");
170 g->trace = str != NULL && strcmp (str, "1") == 0;
172 str = getenv ("LIBGUESTFS_PATH");
173 g->path = str != NULL ? strdup (str) : strdup (GUESTFS_DEFAULT_PATH);
174 if (!g->path) goto error;
176 str = getenv ("LIBGUESTFS_QEMU");
177 g->qemu = str != NULL ? strdup (str) : strdup (QEMU);
178 if (!g->qemu) goto error;
180 str = getenv ("LIBGUESTFS_APPEND");
182 g->append = strdup (str);
183 if (!g->append) goto error;
186 /* Choose a suitable memory size. Previously we tried to choose
187 * a minimal memory size, but this isn't really necessary since
188 * recent QEMU and KVM don't do anything nasty like locking
189 * memory into core any more. Thus we can safely choose a
190 * large, generous amount of memory, and it'll just get swapped
191 * on smaller systems.
193 str = getenv ("LIBGUESTFS_MEMSIZE");
195 if (sscanf (str, "%d", &g->memsize) != 1 || g->memsize <= 256) {
196 fprintf (stderr, "libguestfs: non-numeric or too small value for LIBGUESTFS_MEMSIZE\n");
202 /* Start with large serial numbers so they are easy to spot
203 * inside the protocol.
205 g->msg_next_serial = 0x00123400;
207 /* Link the handles onto a global list. This is the one area
208 * where the library needs to be made thread-safe. (XXX)
210 /* acquire mutex (XXX) */
213 if (!atexit_handler_set) {
214 atexit (close_handles);
215 atexit_handler_set = 1;
217 /* release mutex (XXX) */
220 fprintf (stderr, "new guestfs handle %p\n", g);
233 guestfs_close (guestfs_h *g)
239 if (g->state == NO_HANDLE) {
240 /* Not safe to call 'error' here, so ... */
241 fprintf (stderr, _("guestfs_close: called twice on the same handle\n"));
246 fprintf (stderr, "closing guestfs handle %p (state %d)\n", g, g->state);
248 /* Try to sync if autosync flag is set. */
249 if (g->autosync && g->state == READY) {
250 guestfs_umount_all (g);
254 /* Remove any handlers that might be called back before we kill the
257 g->log_message_cb = NULL;
259 if (g->state != CONFIG)
260 guestfs_kill_subprocess (g);
273 /* Wait for subprocess(es) to exit. */
274 waitpid (g->pid, NULL, 0);
275 if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0);
277 /* Remove tmpfiles. */
279 snprintf (filename, sizeof filename, "%s/sock", g->tmpdir);
282 snprintf (filename, sizeof filename, "%s/initrd", g->tmpdir);
285 snprintf (filename, sizeof filename, "%s/kernel", g->tmpdir);
294 for (i = 0; i < g->cmdline_size; ++i)
295 free (g->cmdline[i]);
299 /* Mark the handle as dead before freeing it. */
300 g->state = NO_HANDLE;
302 /* acquire mutex (XXX) */
306 for (gg = handles; gg->next != g; gg = gg->next)
310 /* release mutex (XXX) */
312 free (g->last_error);
317 free (g->qemu_version);
321 /* Close all open handles (called from atexit(3)). */
325 while (handles) guestfs_close (handles);
329 guestfs_last_error (guestfs_h *g)
331 return g->last_error;
335 set_last_error (guestfs_h *g, const char *msg)
337 free (g->last_error);
338 g->last_error = strdup (msg);
342 default_error_cb (guestfs_h *g, void *data, const char *msg)
344 fprintf (stderr, _("libguestfs: error: %s\n"), msg);
348 guestfs_error (guestfs_h *g, const char *fs, ...)
354 int err = vasprintf (&msg, fs, args);
359 if (g->error_cb) g->error_cb (g, g->error_cb_data, msg);
360 set_last_error (g, msg);
366 guestfs_perrorf (guestfs_h *g, const char *fs, ...)
373 int err = vasprintf (&msg, fs, args);
380 strerror_r (errnum, buf, sizeof buf);
384 buf = strerror_r (errnum, _buf, sizeof _buf);
387 msg = safe_realloc (g, msg, strlen (msg) + 2 + strlen (buf) + 1);
391 if (g->error_cb) g->error_cb (g, g->error_cb_data, msg);
392 set_last_error (g, msg);
398 guestfs_safe_malloc (guestfs_h *g, size_t nbytes)
400 void *ptr = malloc (nbytes);
401 if (nbytes > 0 && !ptr) g->abort_cb ();
405 /* Return 1 if an array of N objects, each of size S, cannot exist due
406 to size arithmetic overflow. S must be positive and N must be
407 nonnegative. This is a macro, not an inline function, so that it
408 works correctly even when SIZE_MAX < N.
410 By gnulib convention, SIZE_MAX represents overflow in size
411 calculations, so the conservative dividend to use here is
412 SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
413 However, malloc (SIZE_MAX) fails on all known hosts where
414 sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
415 exactly-SIZE_MAX allocations on such hosts; this avoids a test and
416 branch when S is known to be 1. */
417 # define xalloc_oversized(n, s) \
418 ((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
420 /* Technically we should add an autoconf test for this, testing for the desired
421 functionality, like what's done in gnulib, but for now, this is fine. */
422 #define HAVE_GNU_CALLOC (__GLIBC__ >= 2)
424 /* Allocate zeroed memory for N elements of S bytes, with error
425 checking. S must be nonzero. */
427 guestfs_safe_calloc (guestfs_h *g, size_t n, size_t s)
429 /* From gnulib's calloc function in xmalloc.c. */
431 /* Test for overflow, since some calloc implementations don't have
432 proper overflow checks. But omit overflow and size-zero tests if
433 HAVE_GNU_CALLOC, since GNU calloc catches overflow and never
434 returns NULL if successful. */
435 if ((! HAVE_GNU_CALLOC && xalloc_oversized (n, s))
436 || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0)))
442 guestfs_safe_realloc (guestfs_h *g, void *ptr, int nbytes)
444 void *p = realloc (ptr, nbytes);
445 if (nbytes > 0 && !p) g->abort_cb ();
450 guestfs_safe_strdup (guestfs_h *g, const char *str)
452 char *s = strdup (str);
453 if (!s) g->abort_cb ();
458 guestfs_safe_memdup (guestfs_h *g, void *ptr, size_t size)
460 void *p = malloc (size);
461 if (!p) g->abort_cb ();
462 memcpy (p, ptr, size);
467 xwrite (int fd, const void *v_buf, size_t len)
469 const char *buf = v_buf;
473 r = write (fd, buf, len);
485 guestfs_set_out_of_memory_handler (guestfs_h *g, guestfs_abort_cb cb)
491 guestfs_get_out_of_memory_handler (guestfs_h *g)
497 guestfs_set_error_handler (guestfs_h *g, guestfs_error_handler_cb cb, void *data)
500 g->error_cb_data = data;
503 guestfs_error_handler_cb
504 guestfs_get_error_handler (guestfs_h *g, void **data_rtn)
506 if (data_rtn) *data_rtn = g->error_cb_data;
511 guestfs__set_verbose (guestfs_h *g, int v)
518 guestfs__get_verbose (guestfs_h *g)
524 guestfs__set_autosync (guestfs_h *g, int a)
531 guestfs__get_autosync (guestfs_h *g)
537 guestfs__set_path (guestfs_h *g, const char *path)
544 safe_strdup (g, GUESTFS_DEFAULT_PATH) : safe_strdup (g, path);
549 guestfs__get_path (guestfs_h *g)
555 guestfs__set_qemu (guestfs_h *g, const char *qemu)
560 g->qemu = qemu == NULL ? safe_strdup (g, QEMU) : safe_strdup (g, qemu);
565 guestfs__get_qemu (guestfs_h *g)
571 guestfs__set_append (guestfs_h *g, const char *append)
576 g->append = append ? safe_strdup (g, append) : NULL;
581 guestfs__get_append (guestfs_h *g)
587 guestfs__set_memsize (guestfs_h *g, int memsize)
589 g->memsize = memsize;
594 guestfs__get_memsize (guestfs_h *g)
600 guestfs__set_selinux (guestfs_h *g, int selinux)
602 g->selinux = selinux;
607 guestfs__get_selinux (guestfs_h *g)
613 guestfs__get_pid (guestfs_h *g)
618 error (g, "get_pid: no qemu subprocess");
623 struct guestfs_version *
624 guestfs__version (guestfs_h *g)
626 struct guestfs_version *r;
628 r = safe_malloc (g, sizeof *r);
629 r->major = PACKAGE_VERSION_MAJOR;
630 r->minor = PACKAGE_VERSION_MINOR;
631 r->release = PACKAGE_VERSION_RELEASE;
632 r->extra = safe_strdup (g, PACKAGE_VERSION_EXTRA);
637 guestfs__set_trace (guestfs_h *g, int t)
644 guestfs__get_trace (guestfs_h *g)
649 /* Add a string to the current command line. */
651 incr_cmdline_size (guestfs_h *g)
653 if (g->cmdline == NULL) {
654 /* g->cmdline[0] is reserved for argv[0], set in guestfs_launch. */
656 g->cmdline = safe_malloc (g, sizeof (char *));
657 g->cmdline[0] = NULL;
661 g->cmdline = safe_realloc (g, g->cmdline, sizeof (char *) * g->cmdline_size);
665 add_cmdline (guestfs_h *g, const char *str)
667 if (g->state != CONFIG) {
669 _("command line cannot be altered after qemu subprocess launched"));
673 incr_cmdline_size (g);
674 g->cmdline[g->cmdline_size-1] = safe_strdup (g, str);
679 guestfs__config (guestfs_h *g,
680 const char *qemu_param, const char *qemu_value)
682 if (qemu_param[0] != '-') {
683 error (g, _("guestfs_config: parameter must begin with '-' character"));
687 /* A bit fascist, but the user will probably break the extra
688 * parameters that we add if they try to set any of these.
690 if (strcmp (qemu_param, "-kernel") == 0 ||
691 strcmp (qemu_param, "-initrd") == 0 ||
692 strcmp (qemu_param, "-nographic") == 0 ||
693 strcmp (qemu_param, "-serial") == 0 ||
694 strcmp (qemu_param, "-full-screen") == 0 ||
695 strcmp (qemu_param, "-std-vga") == 0 ||
696 strcmp (qemu_param, "-vnc") == 0) {
697 error (g, _("guestfs_config: parameter '%s' isn't allowed"), qemu_param);
701 if (add_cmdline (g, qemu_param) != 0) return -1;
703 if (qemu_value != NULL) {
704 if (add_cmdline (g, qemu_value) != 0) return -1;
711 guestfs__add_drive (guestfs_h *g, const char *filename)
713 size_t len = strlen (filename) + 64;
716 if (strchr (filename, ',') != NULL) {
717 error (g, _("filename cannot contain ',' (comma) character"));
721 /* cache=off improves reliability in the event of a host crash.
723 * However this option causes qemu to try to open the file with
724 * O_DIRECT. This fails on some filesystem types (notably tmpfs).
725 * So we check if we can open the file with or without O_DIRECT,
726 * and use cache=off (or not) accordingly.
728 * This test also checks for the presence of the file, which
729 * is a documented semantic of this interface.
731 int fd = open (filename, O_RDONLY|O_DIRECT);
734 snprintf (buf, len, "file=%s,cache=off,if=" DRIVE_IF, filename);
736 fd = open (filename, O_RDONLY);
739 snprintf (buf, len, "file=%s,if=" DRIVE_IF, filename);
741 perrorf (g, "%s", filename);
746 return guestfs__config (g, "-drive", buf);
750 guestfs__add_drive_ro (guestfs_h *g, const char *filename)
752 size_t len = strlen (filename) + 64;
755 if (strchr (filename, ',') != NULL) {
756 error (g, _("filename cannot contain ',' (comma) character"));
760 if (access (filename, F_OK) == -1) {
761 perrorf (g, "%s", filename);
765 snprintf (buf, len, "file=%s,snapshot=on,if=%s", filename, DRIVE_IF);
767 return guestfs__config (g, "-drive", buf);
771 guestfs__add_cdrom (guestfs_h *g, const char *filename)
773 if (strchr (filename, ',') != NULL) {
774 error (g, _("filename cannot contain ',' (comma) character"));
778 if (access (filename, F_OK) == -1) {
779 perrorf (g, "%s", filename);
783 return guestfs__config (g, "-cdrom", filename);
786 /* Returns true iff file is contained in dir. */
788 dir_contains_file (const char *dir, const char *file)
790 int dirlen = strlen (dir);
791 int filelen = strlen (file);
792 int len = dirlen+filelen+2;
795 snprintf (path, len, "%s/%s", dir, file);
796 return access (path, F_OK) == 0;
799 /* Returns true iff every listed file is contained in 'dir'. */
801 dir_contains_files (const char *dir, ...)
806 va_start (args, dir);
807 while ((file = va_arg (args, const char *)) != NULL) {
808 if (!dir_contains_file (dir, file)) {
817 static int build_supermin_appliance (guestfs_h *g, const char *path, char **kernel, char **initrd);
818 static int test_qemu (guestfs_h *g);
819 static int qemu_supports (guestfs_h *g, const char *option);
820 static void print_cmdline (guestfs_h *g);
822 static const char *kernel_name = "vmlinuz." REPO "." host_cpu;
823 static const char *initrd_name = "initramfs." REPO "." host_cpu ".img";
824 static const char *supermin_name =
825 "initramfs." REPO "." host_cpu ".supermin.img";
826 static const char *supermin_hostfiles_name =
827 "initramfs." REPO "." host_cpu ".supermin.hostfiles";
830 guestfs__launch (guestfs_h *g)
833 char dir_template[PATH_MAX];
838 char *path, *pelem, *pend;
839 char *kernel = NULL, *initrd = NULL;
841 struct sockaddr_un addr;
849 tmpdir = getenv ("TMPDIR") ? : tmpdir;
850 snprintf (dir_template, sizeof dir_template, "%s/libguestfsXXXXXX", tmpdir);
854 error (g, _("you must call guestfs_add_drive before guestfs_launch"));
858 if (g->state != CONFIG) {
859 error (g, _("qemu has already been launched"));
863 /* Make the temporary directory. */
865 g->tmpdir = safe_strdup (g, dir_template);
866 if (mkdtemp (g->tmpdir) == NULL) {
867 perrorf (g, _("%s: cannot create temporary directory"), dir_template);
872 /* First search g->path for the supermin appliance, and try to
873 * synthesize a kernel and initrd from that. If it fails, we
874 * try the path search again looking for a backup ordinary
877 pelem = path = safe_strdup (g, g->path);
879 pend = strchrnul (pelem, ':');
880 pmore = *pend == ':';
884 /* Empty element of "." means cwd. */
885 if (len == 0 || (len == 1 && *pelem == '.')) {
888 "looking for supermin appliance in current directory\n");
889 if (dir_contains_files (".",
890 supermin_name, supermin_hostfiles_name,
891 "kmod.whitelist", NULL)) {
892 if (build_supermin_appliance (g, ".", &kernel, &initrd) == -1)
897 /* Look at <path>/supermin* etc. */
900 fprintf (stderr, "looking for supermin appliance in %s\n", pelem);
902 if (dir_contains_files (pelem,
903 supermin_name, supermin_hostfiles_name,
904 "kmod.whitelist", NULL)) {
905 if (build_supermin_appliance (g, pelem, &kernel, &initrd) == -1)
916 if (kernel == NULL || initrd == NULL) {
917 /* Search g->path for the kernel and initrd. */
918 pelem = path = safe_strdup (g, g->path);
920 pend = strchrnul (pelem, ':');
921 pmore = *pend == ':';
925 /* Empty element or "." means cwd. */
926 if (len == 0 || (len == 1 && *pelem == '.')) {
929 "looking for appliance in current directory\n");
930 if (dir_contains_files (".", kernel_name, initrd_name, NULL)) {
931 kernel = safe_strdup (g, kernel_name);
932 initrd = safe_strdup (g, initrd_name);
936 /* Look at <path>/kernel etc. */
939 fprintf (stderr, "looking for appliance in %s\n", pelem);
941 if (dir_contains_files (pelem, kernel_name, initrd_name, NULL)) {
942 kernel = safe_malloc (g, len + strlen (kernel_name) + 2);
943 initrd = safe_malloc (g, len + strlen (initrd_name) + 2);
944 sprintf (kernel, "%s/%s", pelem, kernel_name);
945 sprintf (initrd, "%s/%s", pelem, initrd_name);
956 if (kernel == NULL || initrd == NULL) {
957 error (g, _("cannot find %s or %s on LIBGUESTFS_PATH (current path = %s)"),
958 kernel_name, initrd_name, g->path);
962 /* Get qemu help text and version. */
963 if (test_qemu (g) == -1)
966 /* Make the vmchannel socket. */
967 snprintf (unixsock, sizeof unixsock, "%s/sock", g->tmpdir);
970 if (pipe (wfd) == -1 || pipe (rfd) == -1) {
985 if (r == 0) { /* Child (qemu). */
988 /* Set up the full command line. Do this in the subprocess so we
989 * don't need to worry about cleaning up.
991 g->cmdline[0] = g->qemu;
993 snprintf (buf, sizeof buf, "%d", g->memsize);
994 add_cmdline (g, "-m");
995 add_cmdline (g, buf);
997 add_cmdline (g, "-no-reboot"); /* Force exit instead of reboot on panic */
998 add_cmdline (g, "-nographic");
999 add_cmdline (g, "-serial");
1000 add_cmdline (g, "stdio");
1002 /* These options recommended by KVM developers to improve reliability. */
1003 if (qemu_supports (g, "-no-hpet"))
1004 add_cmdline (g, "-no-hpet");
1006 if (qemu_supports (g, "-rtc-td-hack"))
1007 add_cmdline (g, "-rtc-td-hack");
1009 if (qemu_supports (g, "-chardev") && qemu_supports (g, "guestfwd")) {
1010 /* New-style -net user,guestfwd=... syntax for guestfwd. See:
1012 * http://git.savannah.gnu.org/cgit/qemu.git/commit/?id=c92ef6a22d3c71538fcc48fb61ad353f7ba03b62
1014 * The original suggested format doesn't work, see:
1016 * http://lists.gnu.org/archive/html/qemu-devel/2009-07/msg01654.html
1018 * However Gerd Hoffman privately suggested to me using -chardev
1019 * instead, which does work.
1021 snprintf (buf, sizeof buf,
1022 "socket,id=guestfsvmc,path=%s,server,nowait", unixsock);
1024 add_cmdline (g, "-chardev");
1025 add_cmdline (g, buf);
1027 snprintf (buf, sizeof buf,
1028 "user,vlan=0,net=10.0.2.0/8,"
1029 "guestfwd=tcp:%s:%d-chardev:guestfsvmc",
1030 GUESTFWD_ADDR, GUESTFWD_PORT);
1032 add_cmdline (g, "-net");
1033 add_cmdline (g, buf);
1035 /* Not guestfwd. HOPEFULLY this qemu uses the older -net channel
1036 * syntax, or if not then we'll get a quick failure.
1038 snprintf (buf, sizeof buf,
1039 "channel,%d:unix:%s,server,nowait", GUESTFWD_PORT, unixsock);
1041 add_cmdline (g, "-net");
1042 add_cmdline (g, buf);
1043 add_cmdline (g, "-net");
1044 add_cmdline (g, "user,vlan=0,net=10.0.2.0/8");
1046 add_cmdline (g, "-net");
1047 add_cmdline (g, "nic,model=" NET_IF ",vlan=0");
1049 #define LINUX_CMDLINE \
1050 "panic=1 " /* force kernel to panic if daemon exits */ \
1051 "console=ttyS0 " /* serial console */ \
1052 "udevtimeout=300 " /* good for very slow systems (RHBZ#480319) */ \
1053 "noapic " /* workaround for RHBZ#502058 - ok if not SMP */ \
1054 "acpi=off " /* we don't need ACPI, turn it off */ \
1055 "cgroup_disable=memory " /* saves us about 5 MB of RAM */
1057 /* Linux kernel command line. */
1058 snprintf (buf, sizeof buf,
1060 "%s" /* (selinux) */
1061 "%s" /* (verbose) */
1062 "%s", /* (append) */
1063 g->selinux ? "selinux=1 enforcing=0 " : "selinux=0 ",
1064 g->verbose ? "guestfs_verbose=1 " : " ",
1065 g->append ? g->append : "");
1067 add_cmdline (g, "-kernel");
1068 add_cmdline (g, (char *) kernel);
1069 add_cmdline (g, "-initrd");
1070 add_cmdline (g, (char *) initrd);
1071 add_cmdline (g, "-append");
1072 add_cmdline (g, buf);
1074 /* Finish off the command line. */
1075 incr_cmdline_size (g);
1076 g->cmdline[g->cmdline_size-1] = NULL;
1081 /* Set up stdin, stdout. */
1087 if (dup (wfd[0]) == -1) {
1089 perror ("dup failed");
1092 if (dup (rfd[1]) == -1)
1099 /* Set up a new process group, so we can signal this process
1100 * and all subprocesses (eg. if qemu is really a shell script).
1105 execv (g->qemu, g->cmdline); /* Run qemu. */
1110 /* Parent (library). */
1118 /* Fork the recovery process off which will kill qemu if the parent
1119 * process fails to do so (eg. if the parent segfaults).
1123 pid_t qemu_pid = g->pid;
1124 pid_t parent_pid = getppid ();
1126 /* Writing to argv is hideously complicated and error prone. See:
1127 * http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/ps_status.c?rev=1.33.2.1;content-type=text%2Fplain
1130 /* Loop around waiting for one or both of the other processes to
1131 * disappear. It's fair to say this is very hairy. The PIDs that
1132 * we are looking at might be reused by another process. We are
1133 * effectively polling. Is the cure worse than the disease?
1136 if (kill (qemu_pid, 0) == -1) /* qemu's gone away, we aren't needed */
1138 if (kill (parent_pid, 0) == -1) {
1139 /* Parent's gone away, qemu still around, so kill qemu. */
1147 /* Don't worry, if the fork failed, this will be -1. The recovery
1148 * process isn't essential.
1152 /* Start the clock ... */
1155 /* Close the other ends of the pipe. */
1159 if (fcntl (wfd[1], F_SETFL, O_NONBLOCK) == -1 ||
1160 fcntl (rfd[0], F_SETFL, O_NONBLOCK) == -1) {
1161 perrorf (g, "fcntl");
1165 g->fd[0] = wfd[1]; /* stdin of child */
1166 g->fd[1] = rfd[0]; /* stdout of child */
1168 /* Open the Unix socket. The vmchannel implementation that got
1169 * merged with qemu sucks in a number of ways. Both ends do
1170 * connect(2), which means that no one knows what, if anything, is
1171 * connected to the other end, or if it becomes disconnected. Even
1172 * worse, we have to wait some indeterminate time for qemu to create
1173 * the socket and connect to it (which happens very early in qemu's
1174 * start-up), so any code that uses vmchannel is inherently racy.
1175 * Hence this silly loop.
1177 g->sock = socket (AF_UNIX, SOCK_STREAM, 0);
1178 if (g->sock == -1) {
1179 perrorf (g, "socket");
1183 if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
1184 perrorf (g, "fcntl");
1188 addr.sun_family = AF_UNIX;
1189 strncpy (addr.sun_path, unixsock, UNIX_PATH_MAX);
1190 addr.sun_path[UNIX_PATH_MAX-1] = '\0';
1193 /* Always sleep at least once to give qemu a small chance to start up. */
1196 r = connect (g->sock, (struct sockaddr *) &addr, sizeof addr);
1197 if ((r == -1 && errno == EINPROGRESS) || r == 0)
1200 if (errno != ENOENT)
1201 perrorf (g, "connect");
1206 error (g, _("failed to connect to vmchannel socket"));
1210 g->state = LAUNCHING;
1220 if (g->recoverypid > 0) kill (g->recoverypid, 9);
1221 waitpid (g->pid, NULL, 0);
1222 if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0);
1236 /* This function is used to print the qemu command line before it gets
1237 * executed, when in verbose mode.
1240 print_cmdline (guestfs_h *g)
1245 while (g->cmdline[i]) {
1246 if (g->cmdline[i][0] == '-') /* -option starts a new line */
1247 fprintf (stderr, " \\\n ");
1249 if (i > 0) fputc (' ', stderr);
1251 /* Does it need shell quoting? This only deals with simple cases. */
1252 needs_quote = strcspn (g->cmdline[i], " ") != strlen (g->cmdline[i]);
1254 if (needs_quote) fputc ('\'', stderr);
1255 fprintf (stderr, "%s", g->cmdline[i]);
1256 if (needs_quote) fputc ('\'', stderr);
1260 fputc ('\n', stderr);
1263 /* This function does the hard work of building the supermin appliance
1264 * on the fly. 'path' is the directory containing the control files.
1265 * 'kernel' and 'initrd' are where we will return the names of the
1266 * kernel and initrd (only initrd is built). The work is done by
1267 * an external script. We just tell it where to put the result.
1270 build_supermin_appliance (guestfs_h *g, const char *path,
1271 char **kernel, char **initrd)
1276 len = strlen (g->tmpdir);
1277 *kernel = safe_malloc (g, len + 8);
1278 snprintf (*kernel, len+8, "%s/kernel", g->tmpdir);
1279 *initrd = safe_malloc (g, len + 8);
1280 snprintf (*initrd, len+8, "%s/initrd", g->tmpdir);
1282 snprintf (cmd, sizeof cmd,
1284 "libguestfs-supermin-helper '%s' %s %s",
1286 path, *kernel, *initrd);
1289 if (r == -1 || WEXITSTATUS(r) != 0) {
1290 error (g, _("external command failed: %s"), cmd);
1293 *kernel = *initrd = NULL;
1300 static int read_all (guestfs_h *g, FILE *fp, char **ret);
1302 /* Test qemu binary (or wrapper) runs, and do 'qemu -help' and
1303 * 'qemu -version' so we know what options this qemu supports and
1307 test_qemu (guestfs_h *g)
1312 free (g->qemu_help);
1313 free (g->qemu_version);
1314 g->qemu_help = NULL;
1315 g->qemu_version = NULL;
1317 snprintf (cmd, sizeof cmd, "'%s' -help", g->qemu);
1319 fp = popen (cmd, "r");
1320 /* qemu -help should always work (qemu -version OTOH wasn't
1321 * supported by qemu 0.9). If this command doesn't work then it
1322 * probably indicates that the qemu binary is missing.
1325 /* XXX This error is never printed, even if the qemu binary
1326 * doesn't exist. Why?
1329 perrorf (g, _("%s: command failed: If qemu is located on a non-standard path, try setting the LIBGUESTFS_QEMU environment variable."), cmd);
1333 if (read_all (g, fp, &g->qemu_help) == -1)
1336 if (pclose (fp) == -1)
1339 snprintf (cmd, sizeof cmd, "'%s' -version 2>/dev/null", g->qemu);
1341 fp = popen (cmd, "r");
1343 /* Intentionally ignore errors. */
1344 read_all (g, fp, &g->qemu_version);
1352 read_all (guestfs_h *g, FILE *fp, char **ret)
1359 *ret = safe_realloc (g, *ret, n + 1);
1364 *ret = safe_realloc (g, *ret, n + BUFSIZ);
1366 r = fread (p, 1, BUFSIZ, fp);
1368 perrorf (g, "read");
1375 /* Test if option is supported by qemu command line (just by grepping
1379 qemu_supports (guestfs_h *g, const char *option)
1381 return g->qemu_help && strstr (g->qemu_help, option) != NULL;
1385 guestfs__wait_ready (guestfs_h *g)
1391 if (g->state == READY) return 0;
1393 if (g->state == BUSY) {
1394 error (g, _("qemu has finished launching already"));
1398 if (g->state != LAUNCHING) {
1399 error (g, _("qemu has not been launched yet"));
1403 r = recv_from_daemon (g, &size, &buf);
1406 if (r == -1) return -1;
1408 if (size != GUESTFS_LAUNCH_FLAG) {
1409 error (g, _("guestfs_wait_ready failed, see earlier error messages"));
1413 /* This is possible in some really strange situations, such as
1414 * guestfsd starts up OK but then qemu immediately exits. Check for
1415 * it because the caller is probably expecting to be able to send
1416 * commands after this function returns.
1418 if (g->state != READY) {
1419 error (g, _("qemu launched and contacted daemon, but state != READY"));
1427 guestfs__kill_subprocess (guestfs_h *g)
1429 if (g->state == CONFIG) {
1430 error (g, _("no subprocess to kill"));
1435 fprintf (stderr, "sending SIGTERM to process %d\n", g->pid);
1437 kill (g->pid, SIGTERM);
1438 if (g->recoverypid > 0) kill (g->recoverypid, 9);
1443 /* Access current state. */
1445 guestfs__is_config (guestfs_h *g)
1447 return g->state == CONFIG;
1451 guestfs__is_launching (guestfs_h *g)
1453 return g->state == LAUNCHING;
1457 guestfs__is_ready (guestfs_h *g)
1459 return g->state == READY;
1463 guestfs__is_busy (guestfs_h *g)
1465 return g->state == BUSY;
1469 guestfs__get_state (guestfs_h *g)
1475 guestfs_set_log_message_callback (guestfs_h *g,
1476 guestfs_log_message_cb cb, void *opaque)
1478 g->log_message_cb = cb;
1479 g->log_message_cb_data = opaque;
1483 guestfs_set_subprocess_quit_callback (guestfs_h *g,
1484 guestfs_subprocess_quit_cb cb, void *opaque)
1486 g->subprocess_quit_cb = cb;
1487 g->subprocess_quit_cb_data = opaque;
1491 guestfs_set_launch_done_callback (guestfs_h *g,
1492 guestfs_launch_done_cb cb, void *opaque)
1494 g->launch_done_cb = cb;
1495 g->launch_done_cb_data = opaque;
1498 /*----------------------------------------------------------------------*/
1500 /* This is the code used to send and receive RPC messages and (for
1501 * certain types of message) to perform file transfers. This code is
1502 * driven from the generated actions (src/guestfs-actions.c). There
1503 * are five different cases to consider:
1505 * (1) A non-daemon function. There is no RPC involved at all, it's
1506 * all handled inside the library.
1508 * (2) A simple RPC (eg. "mount"). We write the request, then read
1509 * the reply. The sequence of calls is:
1511 * guestfs___set_busy
1514 * guestfs___end_busy
1516 * (3) An RPC with FileOut parameters (eg. "upload"). We write the
1517 * request, then write the file(s), then read the reply. The sequence
1520 * guestfs___set_busy
1522 * guestfs___send_file (possibly multiple times)
1524 * guestfs___end_busy
1526 * (4) An RPC with FileIn parameters (eg. "download"). We write the
1527 * request, then read the reply, then read the file(s). The sequence
1530 * guestfs___set_busy
1533 * guestfs___recv_file (possibly multiple times)
1534 * guestfs___end_busy
1536 * (5) Both FileOut and FileIn parameters. There are no calls like
1537 * this in the current API, but they would be implemented as a
1538 * combination of cases (3) and (4).
1540 * During all writes and reads, we also select(2) on qemu stdout
1541 * looking for messages (guestfsd stderr and guest kernel dmesg), and
1542 * anything received is passed up through the log_message_cb. This is
1543 * also the reason why all the sockets are non-blocking. We also have
1544 * to check for EOF (qemu died). All of this is handled by the
1545 * functions send_to_daemon and recv_from_daemon.
1549 guestfs___set_busy (guestfs_h *g)
1551 if (g->state != READY) {
1552 error (g, _("guestfs_set_busy: called when in state %d != READY"),
1561 guestfs___end_busy (guestfs_h *g)
1575 error (g, _("guestfs_end_busy: called when in state %d"), g->state);
1581 /* This is called if we detect EOF, ie. qemu died. */
1583 child_cleanup (guestfs_h *g)
1586 fprintf (stderr, "child_cleanup: %p: child process died\n", g);
1588 /*kill (g->pid, SIGTERM);*/
1589 if (g->recoverypid > 0) kill (g->recoverypid, 9);
1590 waitpid (g->pid, NULL, 0);
1591 if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0);
1602 if (g->subprocess_quit_cb)
1603 g->subprocess_quit_cb (g, g->subprocess_quit_cb_data);
1607 read_log_message_or_eof (guestfs_h *g, int fd)
1615 "read_log_message_or_eof: %p g->state = %d, fd = %d\n",
1619 /* QEMU's console emulates a 16550A serial port. The real 16550A
1620 * device has a small FIFO buffer (16 bytes) which means here we see
1621 * lots of small reads of 1-16 bytes in length, usually single
1624 n = read (fd, buf, sizeof buf);
1626 /* Hopefully this indicates the qemu child process has died. */
1632 if (errno == EINTR || errno == EAGAIN)
1635 perrorf (g, "read");
1639 /* In verbose mode, copy all log messages to stderr. */
1641 ignore_value (write (STDERR_FILENO, buf, n));
1643 /* It's an actual log message, send it upwards if anyone is listening. */
1644 if (g->log_message_cb)
1645 g->log_message_cb (g, g->log_message_cb_data, buf, n);
1651 check_for_daemon_cancellation_or_eof (guestfs_h *g, int fd)
1660 "check_for_daemon_cancellation_or_eof: %p g->state = %d, fd = %d\n",
1663 n = read (fd, buf, 4);
1665 /* Hopefully this indicates the qemu child process has died. */
1671 if (errno == EINTR || errno == EAGAIN)
1674 perrorf (g, "read");
1678 xdrmem_create (&xdr, buf, 4, XDR_DECODE);
1679 xdr_uint32_t (&xdr, &flag);
1682 if (flag != GUESTFS_CANCEL_FLAG) {
1683 error (g, _("check_for_daemon_cancellation_or_eof: read 0x%x from daemon, expected 0x%x\n"),
1684 flag, GUESTFS_CANCEL_FLAG);
1691 /* This writes the whole N bytes of BUF to the daemon socket.
1693 * If the whole write is successful, it returns 0.
1694 * If there was an error, it returns -1.
1695 * If the daemon sent a cancellation message, it returns -2.
1697 * It also checks qemu stdout for log messages and passes those up
1698 * through log_message_cb.
1700 * It also checks for EOF (qemu died) and passes that up through the
1701 * child_cleanup function above.
1704 send_to_daemon (guestfs_h *g, const void *v_buf, size_t n)
1706 const char *buf = v_buf;
1712 "send_to_daemon: %p g->state = %d, n = %zu\n", g, g->state, n);
1717 FD_SET (g->fd[1], &rset); /* Read qemu stdout for log messages & EOF. */
1718 FD_SET (g->sock, &rset); /* Read socket for cancellation & EOF. */
1719 FD_SET (g->sock, &wset); /* Write to socket to send the data. */
1721 int max_fd = g->sock > g->fd[1] ? g->sock : g->fd[1];
1726 int r = select (max_fd+1, &rset2, &wset2, NULL, NULL);
1728 if (errno == EINTR || errno == EAGAIN)
1730 perrorf (g, "select");
1734 if (FD_ISSET (g->fd[1], &rset2)) {
1735 if (read_log_message_or_eof (g, g->fd[1]) == -1)
1738 if (FD_ISSET (g->sock, &rset2)) {
1739 r = check_for_daemon_cancellation_or_eof (g, g->sock);
1743 if (FD_ISSET (g->sock, &wset2)) {
1744 r = write (g->sock, buf, n);
1746 if (errno == EINTR || errno == EAGAIN)
1748 perrorf (g, "write");
1749 if (errno == EPIPE) /* Disconnected from guest (RHBZ#508713). */
1761 /* This reads a single message, file chunk, launch flag or
1762 * cancellation flag from the daemon. If something was read, it
1763 * returns 0, otherwise -1.
1765 * Both size_rtn and buf_rtn must be passed by the caller as non-NULL.
1767 * *size_rtn returns the size of the returned message or it may be
1768 * GUESTFS_LAUNCH_FLAG or GUESTFS_CANCEL_FLAG.
1770 * *buf_rtn is returned containing the message (if any) or will be set
1771 * to NULL. *buf_rtn must be freed by the caller.
1773 * It also checks qemu stdout for log messages and passes those up
1774 * through log_message_cb.
1776 * It also checks for EOF (qemu died) and passes that up through the
1777 * child_cleanup function above.
1780 recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn)
1786 "recv_from_daemon: %p g->state = %d, size_rtn = %p, buf_rtn = %p\n",
1787 g, g->state, size_rtn, buf_rtn);
1791 FD_SET (g->fd[1], &rset); /* Read qemu stdout for log messages & EOF. */
1792 FD_SET (g->sock, &rset); /* Read socket for data & EOF. */
1794 int max_fd = g->sock > g->fd[1] ? g->sock : g->fd[1];
1800 /* nr is the size of the message, but we prime it as -4 because we
1801 * have to read the message length word first.
1805 while (nr < (ssize_t) *size_rtn) {
1807 int r = select (max_fd+1, &rset2, NULL, NULL, NULL);
1809 if (errno == EINTR || errno == EAGAIN)
1811 perrorf (g, "select");
1817 if (FD_ISSET (g->fd[1], &rset2)) {
1818 if (read_log_message_or_eof (g, g->fd[1]) == -1) {
1824 if (FD_ISSET (g->sock, &rset2)) {
1825 if (nr < 0) { /* Have we read the message length word yet? */
1826 r = read (g->sock, lenbuf+nr+4, -nr);
1828 if (errno == EINTR || errno == EAGAIN)
1831 perrorf (g, "read");
1832 /* Under some circumstances we see "Connection reset by peer"
1833 * here when the child dies suddenly. Catch this and call
1834 * the cleanup function, same as for EOF.
1836 if (err == ECONNRESET)
1841 error (g, _("unexpected end of file when reading from daemon"));
1847 if (nr < 0) /* Still not got the whole length word. */
1851 xdrmem_create (&xdr, lenbuf, 4, XDR_DECODE);
1852 xdr_uint32_t (&xdr, size_rtn);
1855 if (*size_rtn == GUESTFS_LAUNCH_FLAG) {
1856 if (g->state != LAUNCHING)
1857 error (g, _("received magic signature from guestfsd, but in state %d"),
1861 if (g->launch_done_cb)
1862 g->launch_done_cb (g, g->launch_done_cb_data);
1866 else if (*size_rtn == GUESTFS_CANCEL_FLAG)
1868 /* If this happens, it's pretty bad and we've probably lost
1871 else if (*size_rtn > GUESTFS_MESSAGE_MAX) {
1872 error (g, _("message length (%u) > maximum possible size (%d)"),
1873 (unsigned) *size_rtn, GUESTFS_MESSAGE_MAX);
1877 /* Allocate the complete buffer, size now known. */
1878 *buf_rtn = safe_malloc (g, *size_rtn);
1882 size_t sizetoread = *size_rtn - nr;
1883 if (sizetoread > BUFSIZ) sizetoread = BUFSIZ;
1885 r = read (g->sock, (char *) (*buf_rtn) + nr, sizetoread);
1887 if (errno == EINTR || errno == EAGAIN)
1889 perrorf (g, "read");
1895 error (g, _("unexpected end of file when reading from daemon"));
1905 /* Got the full message, caller can start processing it. */
1906 #ifdef ENABLE_PACKET_DUMP
1910 for (i = 0; i < nr; i += 16) {
1911 printf ("%04zx: ", i);
1912 for (j = i; j < MIN (i+16, nr); ++j)
1913 printf ("%02x ", (*(unsigned char **)buf_rtn)[j]);
1914 for (; j < i+16; ++j)
1917 for (j = i; j < MIN (i+16, nr); ++j)
1918 if (isprint ((*(char **)buf_rtn)[j]))
1919 printf ("%c", (*(char **)buf_rtn)[j]);
1922 for (; j < i+16; ++j)
1933 guestfs___send (guestfs_h *g, int proc_nr, xdrproc_t xdrp, char *args)
1935 struct guestfs_message_header hdr;
1938 int serial = g->msg_next_serial++;
1941 size_t msg_out_size;
1943 if (g->state != BUSY) {
1944 error (g, _("guestfs___send: state %d != BUSY"), g->state);
1948 /* We have to allocate this message buffer on the heap because
1949 * it is quite large (although will be mostly unused). We
1950 * can't allocate it on the stack because in some environments
1951 * we have quite limited stack space available, notably when
1952 * running in the JVM.
1954 msg_out = safe_malloc (g, GUESTFS_MESSAGE_MAX + 4);
1955 xdrmem_create (&xdr, msg_out + 4, GUESTFS_MESSAGE_MAX, XDR_ENCODE);
1957 /* Serialize the header. */
1958 hdr.prog = GUESTFS_PROGRAM;
1959 hdr.vers = GUESTFS_PROTOCOL_VERSION;
1961 hdr.direction = GUESTFS_DIRECTION_CALL;
1962 hdr.serial = serial;
1963 hdr.status = GUESTFS_STATUS_OK;
1965 if (!xdr_guestfs_message_header (&xdr, &hdr)) {
1966 error (g, _("xdr_guestfs_message_header failed"));
1970 /* Serialize the args. If any, because some message types
1971 * have no parameters.
1974 if (!(*xdrp) (&xdr, args)) {
1975 error (g, _("dispatch failed to marshal args"));
1980 /* Get the actual length of the message, resize the buffer to match
1981 * the actual length, and write the length word at the beginning.
1983 len = xdr_getpos (&xdr);
1986 msg_out = safe_realloc (g, msg_out, len + 4);
1987 msg_out_size = len + 4;
1989 xdrmem_create (&xdr, msg_out, 4, XDR_ENCODE);
1990 xdr_uint32_t (&xdr, &len);
1993 r = send_to_daemon (g, msg_out, msg_out_size);
1994 if (r == -2) /* Ignore stray daemon cancellations. */
2007 static int cancel = 0; /* XXX Implement file cancellation. */
2008 static int send_file_chunk (guestfs_h *g, int cancel, const char *buf, size_t len);
2009 static int send_file_data (guestfs_h *g, const char *buf, size_t len);
2010 static int send_file_cancellation (guestfs_h *g);
2011 static int send_file_complete (guestfs_h *g);
2017 * -2 daemon cancelled (we must read the error message)
2020 guestfs___send_file (guestfs_h *g, const char *filename)
2022 char buf[GUESTFS_MAX_CHUNK_SIZE];
2025 fd = open (filename, O_RDONLY);
2027 perrorf (g, "open: %s", filename);
2028 send_file_cancellation (g);
2029 /* Daemon sees cancellation and won't reply, so caller can
2035 /* Send file in chunked encoding. */
2037 r = read (fd, buf, sizeof buf);
2038 if (r == -1 && (errno == EINTR || errno == EAGAIN))
2041 err = send_file_data (g, buf, r);
2043 if (err == -2) /* daemon sent cancellation */
2044 send_file_cancellation (g);
2049 if (cancel) { /* cancel from either end */
2050 send_file_cancellation (g);
2055 perrorf (g, "read: %s", filename);
2056 send_file_cancellation (g);
2060 /* End of file, but before we send that, we need to close
2061 * the file and check for errors.
2063 if (close (fd) == -1) {
2064 perrorf (g, "close: %s", filename);
2065 send_file_cancellation (g);
2069 return send_file_complete (g);
2072 /* Send a chunk of file data. */
2074 send_file_data (guestfs_h *g, const char *buf, size_t len)
2076 return send_file_chunk (g, 0, buf, len);
2079 /* Send a cancellation message. */
2081 send_file_cancellation (guestfs_h *g)
2083 return send_file_chunk (g, 1, NULL, 0);
2086 /* Send a file complete chunk. */
2088 send_file_complete (guestfs_h *g)
2091 return send_file_chunk (g, 0, buf, 0);
2095 send_file_chunk (guestfs_h *g, int cancel, const char *buf, size_t buflen)
2099 guestfs_chunk chunk;
2102 size_t msg_out_size;
2104 if (g->state != BUSY) {
2105 error (g, _("send_file_chunk: state %d != READY"), g->state);
2109 /* Allocate the chunk buffer. Don't use the stack to avoid
2110 * excessive stack usage and unnecessary copies.
2112 msg_out = safe_malloc (g, GUESTFS_MAX_CHUNK_SIZE + 4 + 48);
2113 xdrmem_create (&xdr, msg_out + 4, GUESTFS_MAX_CHUNK_SIZE + 48, XDR_ENCODE);
2115 /* Serialize the chunk. */
2116 chunk.cancel = cancel;
2117 chunk.data.data_len = buflen;
2118 chunk.data.data_val = (char *) buf;
2120 if (!xdr_guestfs_chunk (&xdr, &chunk)) {
2121 error (g, _("xdr_guestfs_chunk failed (buf = %p, buflen = %zu)"),
2127 len = xdr_getpos (&xdr);
2130 /* Reduce the size of the outgoing message buffer to the real length. */
2131 msg_out = safe_realloc (g, msg_out, len + 4);
2132 msg_out_size = len + 4;
2134 xdrmem_create (&xdr, msg_out, 4, XDR_ENCODE);
2135 xdr_uint32_t (&xdr, &len);
2137 r = send_to_daemon (g, msg_out, msg_out_size);
2139 /* Did the daemon send a cancellation message? */
2142 fprintf (stderr, "got daemon cancellation\n");
2158 /* Receive a reply. */
2160 guestfs___recv (guestfs_h *g, const char *fn,
2161 guestfs_message_header *hdr,
2162 guestfs_message_error *err,
2163 xdrproc_t xdrp, char *ret)
2171 r = recv_from_daemon (g, &size, &buf);
2175 /* This can happen if a cancellation happens right at the end
2176 * of us sending a FileIn parameter to the daemon. Discard. The
2177 * daemon should send us an error message next.
2179 if (size == GUESTFS_CANCEL_FLAG)
2182 if (size == GUESTFS_LAUNCH_FLAG) {
2183 error (g, "%s: received unexpected launch flag from daemon when expecting reply", fn);
2187 xdrmem_create (&xdr, buf, size, XDR_DECODE);
2189 if (!xdr_guestfs_message_header (&xdr, hdr)) {
2190 error (g, "%s: failed to parse reply header", fn);
2195 if (hdr->status == GUESTFS_STATUS_ERROR) {
2196 if (!xdr_guestfs_message_error (&xdr, err)) {
2197 error (g, "%s: failed to parse reply error", fn);
2203 if (xdrp && ret && !xdrp (&xdr, ret)) {
2204 error (g, "%s: failed to parse reply", fn);
2216 /* Receive a file. */
2218 /* Returns -1 = error, 0 = EOF, > 0 = more data */
2219 static ssize_t receive_file_data (guestfs_h *g, void **buf);
2222 guestfs___recv_file (guestfs_h *g, const char *filename)
2228 fd = open (filename, O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY, 0666);
2230 perrorf (g, "open: %s", filename);
2234 /* Receive the file in chunked encoding. */
2235 while ((r = receive_file_data (g, &buf)) > 0) {
2236 if (xwrite (fd, buf, r) == -1) {
2237 perrorf (g, "%s: write", filename);
2245 error (g, _("%s: error in chunked encoding"), filename);
2249 if (close (fd) == -1) {
2250 perrorf (g, "close: %s", filename);
2257 /* Send cancellation message to daemon, then wait until it
2258 * cancels (just throwing away data).
2262 uint32_t flag = GUESTFS_CANCEL_FLAG;
2265 fprintf (stderr, "%s: waiting for daemon to acknowledge cancellation\n",
2268 xdrmem_create (&xdr, fbuf, sizeof fbuf, XDR_ENCODE);
2269 xdr_uint32_t (&xdr, &flag);
2272 if (xwrite (g->sock, fbuf, sizeof fbuf) == -1) {
2273 perrorf (g, _("write to daemon socket"));
2277 while (receive_file_data (g, NULL) > 0)
2278 ; /* just discard it */
2283 /* Receive a chunk of file data. */
2284 /* Returns -1 = error, 0 = EOF, > 0 = more data */
2286 receive_file_data (guestfs_h *g, void **buf_r)
2292 guestfs_chunk chunk;
2294 r = recv_from_daemon (g, &len, &buf);
2296 error (g, _("receive_file_data: parse error in reply callback"));
2300 if (len == GUESTFS_LAUNCH_FLAG || len == GUESTFS_CANCEL_FLAG) {
2301 error (g, _("receive_file_data: unexpected flag received when reading file chunks"));
2305 memset (&chunk, 0, sizeof chunk);
2307 xdrmem_create (&xdr, buf, len, XDR_DECODE);
2308 if (!xdr_guestfs_chunk (&xdr, &chunk)) {
2309 error (g, _("failed to parse file chunk"));
2314 /* After decoding, the original buffer is no longer used. */
2318 error (g, _("file receive cancelled by daemon"));
2319 free (chunk.data.data_val);
2323 if (chunk.data.data_len == 0) { /* end of transfer */
2324 free (chunk.data.data_val);
2328 if (buf_r) *buf_r = chunk.data.data_val;
2329 else free (chunk.data.data_val); /* else caller frees */
2331 return chunk.data.data_len;