X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=src%2Fguestfs.c;h=b30ade06e3aed24ecbca3764eb1e8a2b177603ea;hp=fd42f199958996820334230dab908839f6f38243;hb=d901cc916102f1aaccfb73396b48aa303e5b8cd7;hpb=bb07a7f858da5d07c57360e62c0ddfd24ce6be45 diff --git a/src/guestfs.c b/src/guestfs.c index fd42f19..b30ade0 100644 --- a/src/guestfs.c +++ b/src/guestfs.c @@ -29,7 +29,9 @@ #include #include #include +#include #include + #include #include @@ -56,13 +58,6 @@ #include "guestfs.h" #include "guestfs_protocol.h" -void guestfs_error (guestfs_h *g, const char *fs, ...); -void guestfs_perrorf (guestfs_h *g, const char *fs, ...); -void *guestfs_safe_malloc (guestfs_h *g, size_t nbytes); -void *guestfs_safe_realloc (guestfs_h *g, void *ptr, int nbytes); -char *guestfs_safe_strdup (guestfs_h *g, const char *str); -void *guestfs_safe_memdup (guestfs_h *g, void *ptr, size_t size); - #define error guestfs_error #define perrorf guestfs_perrorf #define safe_malloc guestfs_safe_malloc @@ -148,7 +143,8 @@ struct guestfs_h int fd[2]; /* Stdin/stdout of qemu. */ int sock; /* Daemon communications socket. */ - int pid; /* Qemu PID. */ + pid_t pid; /* Qemu PID. */ + pid_t recoverypid; /* Recovery process PID. */ time_t start_t; /* The time when we started qemu. */ int stdout_watch; /* Watches qemu stdout for log messages. */ @@ -162,7 +158,9 @@ struct guestfs_h int verbose; int autosync; - const char *path; + char *path; /* Path to kernel, initrd. */ + char *qemu; /* Qemu binary. */ + char *append; /* Append to kernel command line. */ char *last_error; @@ -223,8 +221,18 @@ guestfs_create (void) g->verbose = str != NULL && strcmp (str, "1") == 0; str = getenv ("LIBGUESTFS_PATH"); - g->path = str != NULL ? str : GUESTFS_DEFAULT_PATH; - /* XXX We should probably make QEMU configurable as well. */ + 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; + } g->main_loop = guestfs_get_default_main_loop (); @@ -249,6 +257,13 @@ guestfs_create (void) 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 @@ -268,8 +283,10 @@ guestfs_close (guestfs_h *g) fprintf (stderr, "closing guestfs handle %p (state %d)\n", g, g->state); /* Try to sync if autosync flag is set. */ - if (g->autosync && g->state == READY) + 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. @@ -307,7 +324,12 @@ guestfs_close (guestfs_h *g) } /* release mutex (XXX) */ + free (g->msg_in); + free (g->msg_out); free (g->last_error); + free (g->path); + free (g->qemu); + free (g->append); free (g); } @@ -416,6 +438,43 @@ guestfs_safe_memdup (guestfs_h *g, void *ptr, size_t size) return p; } +static int +xwrite (int fd, const void *buf, size_t len) +{ + int r; + + while (len > 0) { + r = write (fd, buf, len); + if (r == -1) + return -1; + + buf += r; + len -= r; + } + + return 0; +} + +static int +xread (int fd, void *buf, size_t len) +{ + int r; + + while (len > 0) { + r = read (fd, buf, len); + if (r == -1) { + if (errno == EINTR || errno == EAGAIN) + continue; + return -1; + } + + buf += r; + len -= r; + } + + return 0; +} + void guestfs_set_out_of_memory_handler (guestfs_h *g, guestfs_abort_cb cb) { @@ -471,10 +530,12 @@ guestfs_get_autosync (guestfs_h *g) int guestfs_set_path (guestfs_h *g, const char *path) { - if (path == NULL) - g->path = GUESTFS_DEFAULT_PATH; - else - g->path = path; + free (g->path); + g->path = NULL; + + g->path = + path == NULL ? + safe_strdup (g, GUESTFS_DEFAULT_PATH) : safe_strdup (g, path); return 0; } @@ -484,6 +545,38 @@ guestfs_get_path (guestfs_h *g) return g->path; } +int +guestfs_set_qemu (guestfs_h *g, const char *qemu) +{ + free (g->qemu); + g->qemu = NULL; + + g->qemu = qemu == NULL ? safe_strdup (g, QEMU) : safe_strdup (g, qemu); + return 0; +} + +const char * +guestfs_get_qemu (guestfs_h *g) +{ + return g->qemu; +} + +int +guestfs_set_append (guestfs_h *g, const char *append) +{ + free (g->append); + g->append = NULL; + + g->append = append ? safe_strdup (g, append) : NULL; + return 0; +} + +const char * +guestfs_get_append (guestfs_h *g) +{ + return g->append; +} + /* Add a string to the current command line. */ static void incr_cmdline_size (guestfs_h *g) @@ -548,7 +641,7 @@ guestfs_config (guestfs_h *g, int guestfs_add_drive (guestfs_h *g, const char *filename) { - int len = strlen (filename) + 64; + size_t len = strlen (filename) + 64; char buf[len]; if (strchr (filename, ',') != NULL) { @@ -586,7 +679,8 @@ int guestfs_launch (guestfs_h *g) { static const char *dir_template = "/tmp/libguestfsXXXXXX"; - int r, i, len, pmore; + int r, i, pmore, memsize; + size_t len; int wfd[2], rfd[2]; int tries; const char *kernel_name = "vmlinuz." REPO "." host_cpu; @@ -654,6 +748,15 @@ guestfs_launch (guestfs_h *g) goto cleanup0; } + /* 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. This we can safely choose a + * large, generous amount of memory, and it'll just get swapped + * on smaller systems. + */ + memsize = 384; + /* Make the temporary directory containing the socket. */ if (!g->tmpdir) { g->tmpdir = safe_strdup (g, dir_template); @@ -684,11 +787,12 @@ guestfs_launch (guestfs_h *g) if (r == 0) { /* Child (qemu). */ char vmchannel[256]; char append[256]; + char memsize_str[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[0] = g->qemu; /* Construct the -net channel parameter for qemu. */ snprintf (vmchannel, sizeof vmchannel, @@ -697,11 +801,19 @@ guestfs_launch (guestfs_h *g) /* Linux kernel command line. */ snprintf (append, sizeof append, - "console=ttyS0 guestfs=%s:%d", VMCHANNEL_ADDR, VMCHANNEL_PORT); + "panic=1 console=ttyS0 guestfs=%s:%d%s%s%s", + VMCHANNEL_ADDR, VMCHANNEL_PORT, + g->verbose ? " guestfs_verbose=1" : "", + g->append ? " " : "", g->append ? g->append : ""); + + snprintf (memsize_str, sizeof memsize_str, "%d", memsize); add_cmdline (g, "-m"); - add_cmdline (g, "384"); /* XXX Choose best size. */ + add_cmdline (g, memsize_str); +#if 0 add_cmdline (g, "-no-kqemu"); /* Avoids a warning. */ +#endif + add_cmdline (g, "-no-reboot"); /* Force exit instead of reboot on panic */ add_cmdline (g, "-kernel"); add_cmdline (g, (char *) kernel); add_cmdline (g, "-initrd"); @@ -716,12 +828,12 @@ guestfs_launch (guestfs_h *g) add_cmdline (g, "-net"); add_cmdline (g, "user,vlan=0"); add_cmdline (g, "-net"); - add_cmdline (g, "nic,vlan=0"); + add_cmdline (g, "nic,model=virtio,vlan=0"); incr_cmdline_size (g); g->cmdline[g->cmdline_size-1] = NULL; if (g->verbose) { - fprintf (stderr, "%s", QEMU); + fprintf (stderr, "%s", g->qemu); for (i = 0; g->cmdline[i]; ++i) fprintf (stderr, " %s", g->cmdline[i]); fprintf (stderr, "\n"); @@ -744,14 +856,53 @@ guestfs_launch (guestfs_h *g) setpgid (0, 0); #endif - execv (QEMU, g->cmdline); /* Run qemu. */ - perror (QEMU); + execv (g->qemu, g->cmdline); /* Run qemu. */ + perror (g->qemu); _exit (1); } /* Parent (library). */ g->pid = r; + free (kernel); + kernel = NULL; + free (initrd); + initrd = NULL; + + /* Fork the recovery process off which will kill qemu if the parent + * process fails to do so (eg. if the parent segfaults). + */ + r = fork (); + if (r == 0) { + pid_t qemu_pid = g->pid; + pid_t parent_pid = getppid (); + + /* Writing to argv is hideously complicated and error prone. See: + * http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/ps_status.c?rev=1.33.2.1;content-type=text%2Fplain + */ + + /* Loop around waiting for one or both of the other processes to + * disappear. It's fair to say this is very hairy. The PIDs that + * we are looking at might be reused by another process. We are + * effectively polling. Is the cure worse than the disease? + */ + for (;;) { + if (kill (qemu_pid, 0) == -1) /* qemu's gone away, we aren't needed */ + _exit (0); + if (kill (parent_pid, 0) == -1) { + /* Parent's gone away, qemu still around, so kill qemu. */ + kill (qemu_pid, 9); + _exit (0); + } + sleep (2); + } + } + + /* Don't worry, if the fork failed, this will be -1. The recovery + * process isn't essential. + */ + g->recoverypid = r; + /* Start the clock ... */ time (&g->start_t); @@ -793,10 +944,9 @@ guestfs_launch (guestfs_h *g) addr.sun_path[UNIX_PATH_MAX-1] = '\0'; tries = 100; + /* Always sleep at least once to give qemu a small chance to start up. */ + usleep (10000); while (tries > 0) { - /* Always sleep at least once to give qemu a small chance to start up. */ - usleep (10000); - r = connect (g->sock, (struct sockaddr *) &addr, sizeof addr); if ((r == -1 && errno == EINPROGRESS) || r == 0) goto connected; @@ -804,6 +954,7 @@ guestfs_launch (guestfs_h *g) if (errno != ENOENT) perrorf (g, "connect"); tries--; + usleep (100000); } error (g, "failed to connect to vmchannel socket"); @@ -848,11 +999,14 @@ guestfs_launch (guestfs_h *g) close (wfd[1]); close (rfd[0]); kill (g->pid, 9); + if (g->recoverypid > 0) kill (g->recoverypid, 9); waitpid (g->pid, NULL, 0); + if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0); g->fd[0] = -1; g->fd[1] = -1; g->sock = -1; g->pid = 0; + g->recoverypid = 0; g->start_t = 0; g->stdout_watch = -1; g->sock_watch = -1; @@ -928,6 +1082,7 @@ guestfs_kill_subprocess (guestfs_h *g) fprintf (stderr, "sending SIGTERM to process %d\n", g->pid); kill (g->pid, SIGTERM); + if (g->recoverypid > 0) kill (g->recoverypid, 9); return 0; } @@ -963,6 +1118,47 @@ guestfs_get_state (guestfs_h *g) return g->state; } +int +guestfs_set_ready (guestfs_h *g) +{ + if (g->state != BUSY) { + error (g, "guestfs_set_ready: called when in state %d != BUSY", g->state); + return -1; + } + g->state = READY; + return 0; +} + +int +guestfs_set_busy (guestfs_h *g) +{ + if (g->state != READY) { + error (g, "guestfs_set_busy: called when in state %d != READY", g->state); + return -1; + } + g->state = BUSY; + return 0; +} + +int +guestfs_end_busy (guestfs_h *g) +{ + switch (g->state) + { + case BUSY: + g->state = READY; + break; + case CONFIG: + case READY: + break; + case LAUNCHING: + case NO_HANDLE: + error (g, "guestfs_end_busy: called when in state %d", g->state); + return -1; + } + return 0; +} + /* Structure-freeing functions. These rely on the fact that the * structure format is identical to the XDR format. See note in * generator.ml. @@ -994,6 +1190,39 @@ guestfs_free_lvm_lv_list (struct guestfs_lvm_lv_list *x) free (x); } +/* We don't know if stdout_event or sock_read_event will be the + * first to receive EOF if the qemu process dies. This function + * has the common cleanup code for both. + */ +static void +child_cleanup (guestfs_h *g) +{ + if (g->verbose) + fprintf (stderr, "stdout_event: %p: child process died\n", g); + /*kill (g->pid, SIGTERM);*/ + if (g->recoverypid > 0) kill (g->recoverypid, 9); + waitpid (g->pid, NULL, 0); + if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0); + if (g->stdout_watch >= 0) + g->main_loop->remove_handle (g->main_loop, g, g->stdout_watch); + if (g->sock_watch >= 0) + g->main_loop->remove_handle (g->main_loop, g, g->sock_watch); + close (g->fd[0]); + close (g->fd[1]); + close (g->sock); + g->fd[0] = -1; + g->fd[1] = -1; + g->sock = -1; + g->pid = 0; + g->recoverypid = 0; + g->start_t = 0; + g->stdout_watch = -1; + g->sock_watch = -1; + g->state = CONFIG; + if (g->subprocess_quit_cb) + g->subprocess_quit_cb (g, g->subprocess_quit_cb_data); +} + /* This function is called whenever qemu prints something on stdout. * Qemu's stdout is also connected to the guest's serial console, so * we see kernel messages here too. @@ -1020,32 +1249,12 @@ stdout_event (struct guestfs_main_loop *ml, guestfs_h *g, void *data, n = read (fd, buf, sizeof buf); if (n == 0) { /* Hopefully this indicates the qemu child process has died. */ - if (g->verbose) - fprintf (stderr, "stdout_event: %p: child process died\n", g); - /*kill (g->pid, SIGTERM);*/ - waitpid (g->pid, NULL, 0); - if (g->stdout_watch >= 0) - g->main_loop->remove_handle (g->main_loop, g, g->stdout_watch); - if (g->sock_watch >= 0) - g->main_loop->remove_handle (g->main_loop, g, g->sock_watch); - close (g->fd[0]); - close (g->fd[1]); - close (g->sock); - g->fd[0] = -1; - g->fd[1] = -1; - g->sock = -1; - g->pid = 0; - g->start_t = 0; - g->stdout_watch = -1; - g->sock_watch = -1; - g->state = CONFIG; - if (g->subprocess_quit_cb) - g->subprocess_quit_cb (g, g->subprocess_quit_cb_data); + child_cleanup (g); return; } if (n == -1) { - if (errno != EAGAIN) + if (errno != EINTR && errno != EAGAIN) perrorf (g, "read"); return; } @@ -1067,7 +1276,7 @@ sock_read_event (struct guestfs_main_loop *ml, guestfs_h *g, void *data, int watch, int fd, int events) { XDR xdr; - unsigned len; + u_int32_t len; int n; if (g->verbose) @@ -1086,14 +1295,14 @@ sock_read_event (struct guestfs_main_loop *ml, guestfs_h *g, void *data, } n = read (g->sock, g->msg_in + g->msg_in_size, g->msg_in_allocated - g->msg_in_size); - if (n == 0) - /* Disconnected? Ignore it because stdout_watch will get called - * and will do the cleanup. - */ + if (n == 0) { + /* Disconnected. */ + child_cleanup (g); return; + } if (n == -1) { - if (errno != EAGAIN) + if (errno != EINTR && errno != EAGAIN) perrorf (g, "read"); return; } @@ -1101,6 +1310,7 @@ sock_read_event (struct guestfs_main_loop *ml, guestfs_h *g, void *data, g->msg_in_size += n; /* Have we got enough of a message to be able to process it yet? */ + again: if (g->msg_in_size < 4) return; xdrmem_create (&xdr, g->msg_in, g->msg_in_size, XDR_DECODE); @@ -1113,7 +1323,7 @@ sock_read_event (struct guestfs_main_loop *ml, guestfs_h *g, void *data, * starts up it sends a "magic" value (longer than any possible * message). Check for this. */ - if (len == 0xf5f55ff5) { + if (len == GUESTFS_LAUNCH_FLAG) { if (g->state != LAUNCHING) error (g, "received magic signature from guestfsd, but in state %d", g->state); @@ -1129,7 +1339,19 @@ sock_read_event (struct guestfs_main_loop *ml, guestfs_h *g, void *data, goto cleanup; } - /* If this happens, it's pretty bad and we've probably lost synchronization.*/ + /* This can happen if a cancellation happens right at the end + * of us sending a FileIn parameter to the daemon. Discard. The + * daemon should send us an error message next. + */ + if (len == GUESTFS_CANCEL_FLAG) { + g->msg_in_size -= 4; + memmove (g->msg_in, g->msg_in+4, g->msg_in_size); + goto again; + } + + /* If this happens, it's pretty bad and we've probably lost + * synchronization. + */ if (len > GUESTFS_MESSAGE_MAX) { error (g, "message length (%u) > maximum possible size (%d)", len, GUESTFS_MESSAGE_MAX); @@ -1138,15 +1360,8 @@ sock_read_event (struct guestfs_main_loop *ml, guestfs_h *g, void *data, if (g->msg_in_size-4 < len) return; /* Need more of this message. */ - /* This should not happen, and if it does it probably means we've - * lost all hope of synchronization. - */ - if (g->msg_in_size-4 > len) { - error (g, "len = %d, but msg_in_size-4 = %d", len, g->msg_in_size-4); - goto cleanup; - } - /* Got the full message, begin processing it. */ +#if 0 if (g->verbose) { int i, j; @@ -1167,15 +1382,22 @@ sock_read_event (struct guestfs_main_loop *ml, guestfs_h *g, void *data, printf ("|\n"); } } +#endif /* Not in the expected state. */ if (g->state != BUSY) error (g, "state %d != BUSY", g->state); /* Push the message up to the higher layer. */ - g->state = READY; if (g->reply_cb) g->reply_cb (g, g->reply_cb_data, &xdr); + else + /* This message (probably) should never be printed. */ + fprintf (stderr, "libguesfs: sock_read_event: !!! dropped message !!!\n"); + + g->msg_in_size -= len + 4; + memmove (g->msg_in, g->msg_in+len+4, g->msg_in_size); + if (g->msg_in_size > 0) goto again; cleanup: /* Free the message buffer if it's grown excessively large. */ @@ -1235,7 +1457,7 @@ sock_write_event (struct guestfs_main_loop *ml, guestfs_h *g, void *data, return; if (g->verbose) - fprintf (stderr, "sock_write_event: done writing, switching back to reading events\n"); + fprintf (stderr, "sock_write_event: done writing, calling send_cb\n"); free (g->msg_out); g->msg_out = NULL; @@ -1305,80 +1527,6 @@ guestfs_get_default_main_loop (void) return (guestfs_main_loop *) &default_main_loop; } -/* Dispatch a call (len + header + args) to the remote daemon. This - * function just queues the call in msg_out, to be sent when we next - * enter the main loop. Returns -1 for error, or the message serial - * number. - */ -int -guestfs__send (guestfs_h *g, int proc_nr, xdrproc_t xdrp, char *args) -{ - char buffer[GUESTFS_MESSAGE_MAX]; - struct guestfs_message_header hdr; - XDR xdr; - unsigned len; - int serial = g->msg_next_serial++; - - if (g->state != READY) { - error (g, "dispatch: state %d != READY", g->state); - return -1; - } - - /* Serialize the header. */ - hdr.prog = GUESTFS_PROGRAM; - hdr.vers = GUESTFS_PROTOCOL_VERSION; - hdr.proc = proc_nr; - hdr.direction = GUESTFS_DIRECTION_CALL; - hdr.serial = serial; - hdr.status = GUESTFS_STATUS_OK; - - xdrmem_create (&xdr, buffer, sizeof buffer, XDR_ENCODE); - if (!xdr_guestfs_message_header (&xdr, &hdr)) { - error (g, "xdr_guestfs_message_header failed"); - return -1; - } - - /* Serialize the args. If any, because some message types - * have no parameters. - */ - if (xdrp) { - if (!(*xdrp) (&xdr, args)) { - error (g, "dispatch failed to marshal args"); - return -1; - } - } - - len = xdr_getpos (&xdr); - xdr_destroy (&xdr); - - /* Allocate the outgoing message buffer. */ - g->msg_out = safe_malloc (g, len + 4); - - g->msg_out_size = len + 4; - g->msg_out_pos = 0; - g->state = BUSY; - - xdrmem_create (&xdr, g->msg_out, 4, XDR_ENCODE); - if (!xdr_uint32_t (&xdr, &len)) { - error (g, "xdr_uint32_t failed in dispatch"); - goto cleanup1; - } - - memcpy (g->msg_out + 4, buffer, len); - - if (guestfs__switch_to_sending (g) == -1) - goto cleanup1; - - return serial; - - cleanup1: - free (g->msg_out); - g->msg_out = NULL; - g->msg_out_size = 0; - g->state = READY; - return -1; -} - /* Change the daemon socket handler so that we are now writing. * This sets the handle to sock_write_event. */ @@ -1428,33 +1576,132 @@ guestfs__switch_to_receiving (guestfs_h *g) return 0; } -int -guestfs__send_file_sync (guestfs_main_loop *ml, guestfs_h *g, - const char *filename) +/* Dispatch a call (len + header + args) to the remote daemon, + * synchronously (ie. using the guest's main loop to wait until + * it has been sent). Returns -1 for error, or the serial + * number of the message. + */ +static void +send_cb (guestfs_h *g, void *data) { - return -1; + guestfs_main_loop *ml = guestfs_get_main_loop (g); + + *((int *)data) = 1; + ml->main_loop_quit (ml, g); } int -guestfs__receive_file_sync (guestfs_main_loop *ml, guestfs_h *g, - const char *filename) +guestfs__send_sync (guestfs_h *g, int proc_nr, + xdrproc_t xdrp, char *args) { + struct guestfs_message_header hdr; + XDR xdr; + u_int32_t len; + int serial = g->msg_next_serial++; + int sent; + guestfs_main_loop *ml = guestfs_get_main_loop (g); + + if (g->state != BUSY) { + error (g, "guestfs__send_sync: state %d != BUSY", g->state); + return -1; + } + + /* This is probably an internal error. Or perhaps we should just + * free the buffer anyway? + */ + if (g->msg_out != NULL) { + error (g, "guestfs__send_sync: msg_out should be NULL"); + return -1; + } + + /* We have to allocate this message buffer on the heap because + * it is quite large (although will be mostly unused). We + * can't allocate it on the stack because in some environments + * we have quite limited stack space available, notably when + * running in the JVM. + */ + g->msg_out = safe_malloc (g, GUESTFS_MESSAGE_MAX + 4); + xdrmem_create (&xdr, g->msg_out + 4, GUESTFS_MESSAGE_MAX, XDR_ENCODE); + + /* Serialize the header. */ + hdr.prog = GUESTFS_PROGRAM; + hdr.vers = GUESTFS_PROTOCOL_VERSION; + hdr.proc = proc_nr; + hdr.direction = GUESTFS_DIRECTION_CALL; + hdr.serial = serial; + hdr.status = GUESTFS_STATUS_OK; + + if (!xdr_guestfs_message_header (&xdr, &hdr)) { + error (g, "xdr_guestfs_message_header failed"); + goto cleanup1; + } + + /* Serialize the args. If any, because some message types + * have no parameters. + */ + if (xdrp) { + if (!(*xdrp) (&xdr, args)) { + error (g, "dispatch failed to marshal args"); + goto cleanup1; + } + } + + /* Get the actual length of the message, resize the buffer to match + * the actual length, and write the length word at the beginning. + */ + len = xdr_getpos (&xdr); + xdr_destroy (&xdr); + + g->msg_out = safe_realloc (g, g->msg_out, len + 4); + g->msg_out_size = len + 4; + g->msg_out_pos = 0; + + xdrmem_create (&xdr, g->msg_out, 4, XDR_ENCODE); + xdr_uint32_t (&xdr, &len); + + if (guestfs__switch_to_sending (g) == -1) + goto cleanup1; + + sent = 0; + guestfs_set_send_callback (g, send_cb, &sent); + if (ml->main_loop_run (ml, g) == -1) + goto cleanup1; + if (sent != 1) { + error (g, "send failed, see earlier error messages"); + goto cleanup1; + } + + return serial; + + cleanup1: + free (g->msg_out); + g->msg_out = NULL; + g->msg_out_size = 0; return -1; } -#if 0 static int cancel = 0; /* XXX Implement file cancellation. */ - +static int send_file_chunk_sync (guestfs_h *g, int cancel, const char *buf, size_t len); +static int send_file_data_sync (guestfs_h *g, const char *buf, size_t len); +static int send_file_cancellation_sync (guestfs_h *g); +static int send_file_complete_sync (guestfs_h *g); + +/* Synchronously send a file. + * Returns: + * 0 OK + * -1 error + * -2 daemon cancelled (we must read the error message) + */ int -guestfs__send_file (guestfs_h *g, const char *filename) +guestfs__send_file_sync (guestfs_h *g, const char *filename) { char buf[GUESTFS_MAX_CHUNK_SIZE]; - int fd, r; + int fd, r, err; fd = open (filename, O_RDONLY); if (fd == -1) { perrorf (g, "open: %s", filename); - send_file_cancellation (g); + send_file_cancellation_sync (g); /* Daemon sees cancellation and won't reply, so caller can * just return here. */ @@ -1462,19 +1709,27 @@ guestfs__send_file (guestfs_h *g, const char *filename) } /* Send file in chunked encoding. */ - while (!cancel && (r = read (fd, buf, sizeof buf)) > 0) { - if (send_file_data (g, buf, r) == -1) - return -1; + while (!cancel) { + r = read (fd, buf, sizeof buf); + if (r == -1 && (errno == EINTR || errno == EAGAIN)) + continue; + if (r <= 0) break; + err = send_file_data_sync (g, buf, r); + if (err < 0) { + if (err == -2) /* daemon sent cancellation */ + send_file_cancellation_sync (g); + return err; + } } - if (cancel) { - send_file_cancellation (g); + if (cancel) { /* cancel from either end */ + send_file_cancellation_sync (g); return -1; } if (r == -1) { perrorf (g, "read: %s", filename); - send_file_cancellation (g); + send_file_cancellation_sync (g); return -1; } @@ -1483,86 +1738,342 @@ guestfs__send_file (guestfs_h *g, const char *filename) */ if (close (fd) == -1) { perrorf (g, "close: %s", filename); - send_file_cancellation (g); + send_file_cancellation_sync (g); return -1; } - return send_file_complete (g); + return send_file_complete_sync (g); } -/* Send a chunk, cancellation or end of file, wait for it to go. */ +/* Send a chunk of file data. */ static int -send_file_chunk (guestfs_h *g, int cancel, const char *buf, size_t len) +send_file_data_sync (guestfs_h *g, const char *buf, size_t len) { - void *data; + return send_file_chunk_sync (g, 0, buf, len); +} + +/* Send a cancellation message. */ +static int +send_file_cancellation_sync (guestfs_h *g) +{ + return send_file_chunk_sync (g, 1, NULL, 0); +} + +/* Send a file complete chunk. */ +static int +send_file_complete_sync (guestfs_h *g) +{ + char buf[1]; + return send_file_chunk_sync (g, 0, buf, 0); +} + +/* Send a chunk, cancellation or end of file, synchronously (ie. wait + * for it to go). + */ +static int check_for_daemon_cancellation (guestfs_h *g); + +static int +send_file_chunk_sync (guestfs_h *g, int cancel, const char *buf, size_t buflen) +{ + u_int32_t len; + int sent; guestfs_chunk chunk; XDR xdr; + guestfs_main_loop *ml = guestfs_get_main_loop (g); if (g->state != BUSY) { - error (g, "send_file_chunk: state %d != READY", g->state); + error (g, "send_file_chunk_sync: state %d != READY", g->state); + return -1; + } + + /* This is probably an internal error. Or perhaps we should just + * free the buffer anyway? + */ + if (g->msg_out != NULL) { + error (g, "guestfs__send_sync: msg_out should be NULL"); return -1; } + /* Did the daemon send a cancellation message? */ + if (check_for_daemon_cancellation (g)) { + if (g->verbose) + fprintf (stderr, "got daemon cancellation\n"); + return -2; + } + + /* Allocate the chunk buffer. Don't use the stack to avoid + * excessive stack usage and unnecessary copies. + */ + g->msg_out = safe_malloc (g, GUESTFS_MAX_CHUNK_SIZE + 4 + 48); + xdrmem_create (&xdr, g->msg_out + 4, GUESTFS_MAX_CHUNK_SIZE + 48, XDR_ENCODE); + /* Serialize the chunk. */ chunk.cancel = cancel; - chunk.data.data_len = len; + chunk.data.data_len = buflen; chunk.data.data_val = (char *) buf; - data = safe_malloc (g, GUESTFS_MAX_CHUNK_SIZE + 48); - xdrmem_create (&xdr, data, GUESTFS_MAX_CHUNK_SIZE + 48, XDR_ENCODE); - if (xdr_guestfs_chunk (&xdr, &chunk)) { - error (g, "xdr_guestfs_chunk failed"); - free (data); - return -1; + if (!xdr_guestfs_chunk (&xdr, &chunk)) { + error (g, "xdr_guestfs_chunk failed (buf = %p, buflen = %zu)", + buf, buflen); + xdr_destroy (&xdr); + goto cleanup1; } - chunkdatalen = xdr_getpos (&xdr); - xdr_destroy (&xdr); - len = xdr_getpos (&xdr); xdr_destroy (&xdr); - data = safe_realloc (g, data, len); - g->msg_out = data; - g->msg_out_size = len; + /* Reduce the size of the outgoing message buffer to the real length. */ + g->msg_out = safe_realloc (g, g->msg_out, len + 4); + g->msg_out_size = len + 4; g->msg_out_pos = 0; + xdrmem_create (&xdr, g->msg_out, 4, XDR_ENCODE); + xdr_uint32_t (&xdr, &len); + if (guestfs__switch_to_sending (g) == -1) goto cleanup1; + sent = 0; + guestfs_set_send_callback (g, send_cb, &sent); + if (ml->main_loop_run (ml, g) == -1) + goto cleanup1; + if (sent != 1) { + error (g, "send file chunk failed, see earlier error messages"); + goto cleanup1; + } + return 0; cleanup1: free (g->msg_out); g->msg_out = NULL; g->msg_out_size = 0; - g->state = READY; return -1; } -/* Send a chunk of file data. */ +/* At this point we are sending FileIn file(s) to the guest, and not + * expecting to read anything, so if we do read anything, it must be + * a cancellation message. This checks for this case without blocking. + */ static int -send_file_data (guestfs_h *g, const char *buf, size_t len) +check_for_daemon_cancellation (guestfs_h *g) { - return send_file_chunk (g, 0, buf, len); + fd_set rset; + struct timeval tv; + int r; + char buf[4]; + uint32_t flag; + XDR xdr; + + FD_ZERO (&rset); + FD_SET (g->sock, &rset); + tv.tv_sec = 0; + tv.tv_usec = 0; + r = select (g->sock+1, &rset, NULL, NULL, &tv); + if (r == -1) { + perrorf (g, "select"); + return 0; + } + if (r == 0) + return 0; + + /* Read the message from the daemon. */ + r = xread (g->sock, buf, sizeof buf); + if (r == -1) { + perrorf (g, "read"); + return 0; + } + + xdrmem_create (&xdr, buf, sizeof buf, XDR_DECODE); + xdr_uint32_t (&xdr, &flag); + xdr_destroy (&xdr); + + if (flag != GUESTFS_CANCEL_FLAG) { + error (g, "check_for_daemon_cancellation: read 0x%x from daemon, expected 0x%x\n", + flag, GUESTFS_CANCEL_FLAG); + return 0; + } + + return 1; } -/* Send a cancellation message. */ -static int -send_file_cancellation (guestfs_h *g) +/* Synchronously receive a file. */ + +/* Returns -1 = error, 0 = EOF, 1 = more data */ +static int receive_file_data_sync (guestfs_h *g, void **buf, size_t *len); + +int +guestfs__receive_file_sync (guestfs_h *g, const char *filename) { - char buf[1]; - return send_file_chunk (g, 1, buf, 0); + void *buf; + int fd, r; + size_t len; + + fd = open (filename, O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY, 0666); + if (fd == -1) { + perrorf (g, "open: %s", filename); + goto cancel; + } + + /* Receive the file in chunked encoding. */ + while ((r = receive_file_data_sync (g, &buf, &len)) >= 0) { + if (xwrite (fd, buf, len) == -1) { + perrorf (g, "%s: write", filename); + free (buf); + goto cancel; + } + free (buf); + if (r == 0) break; /* End of file. */ + } + + if (r == -1) { + error (g, "%s: error in chunked encoding", filename); + return -1; + } + + if (close (fd) == -1) { + perrorf (g, "close: %s", filename); + return -1; + } + + return 0; + + cancel: ; + /* Send cancellation message to daemon, then wait until it + * cancels (just throwing away data). + */ + XDR xdr; + char fbuf[4]; + uint32_t flag = GUESTFS_CANCEL_FLAG; + + xdrmem_create (&xdr, fbuf, sizeof fbuf, XDR_ENCODE); + xdr_uint32_t (&xdr, &flag); + xdr_destroy (&xdr); + + if (xwrite (g->sock, fbuf, sizeof fbuf) == -1) { + perrorf (g, "write to daemon socket"); + return -1; + } + + while ((r = receive_file_data_sync (g, NULL, NULL)) > 0) + ; /* just discard it */ + + return -1; } -/* Send a file complete chunk. */ +/* Note that the reply callback can be called multiple times before + * the main loop quits and we get back to the synchronous code. So + * we have to be prepared to save multiple chunks on a list here. + */ +struct receive_file_ctx { + int count; /* 0 if receive_file_cb not called, or + * else count number of chunks. + */ + guestfs_chunk *chunks; /* Array of chunks. */ +}; + +static void +free_chunks (struct receive_file_ctx *ctx) +{ + int i; + + for (i = 0; i < ctx->count; ++i) + free (ctx->chunks[i].data.data_val); + + free (ctx->chunks); +} + +static void +receive_file_cb (guestfs_h *g, void *data, XDR *xdr) +{ + guestfs_main_loop *ml = guestfs_get_main_loop (g); + struct receive_file_ctx *ctx = (struct receive_file_ctx *) data; + guestfs_chunk chunk; + + if (ctx->count == -1) /* Parse error occurred previously. */ + return; + + ml->main_loop_quit (ml, g); + + memset (&chunk, 0, sizeof chunk); + + if (!xdr_guestfs_chunk (xdr, &chunk)) { + error (g, "failed to parse file chunk"); + free_chunks (ctx); + ctx->chunks = NULL; + ctx->count = -1; + return; + } + + /* Copy the chunk to the list. */ + ctx->chunks = safe_realloc (g, ctx->chunks, + sizeof (guestfs_chunk) * (ctx->count+1)); + ctx->chunks[ctx->count] = chunk; + ctx->count++; +} + +/* Receive a chunk of file data. */ +/* Returns -1 = error, 0 = EOF, 1 = more data */ static int -send_file_complete (guestfs_h *g) +receive_file_data_sync (guestfs_h *g, void **buf, size_t *len_r) { - char buf[0]; - return send_file_chunk (g, 0, buf, 0); + struct receive_file_ctx ctx; + guestfs_main_loop *ml = guestfs_get_main_loop (g); + int i; + size_t len; + + ctx.count = 0; + ctx.chunks = NULL; + + guestfs_set_reply_callback (g, receive_file_cb, &ctx); + (void) ml->main_loop_run (ml, g); + guestfs_set_reply_callback (g, NULL, NULL); + + if (ctx.count == 0) { + error (g, "receive_file_data_sync: reply callback not called\n"); + return -1; + } + + if (ctx.count == -1) { + error (g, "receive_file_data_sync: parse error in reply callback\n"); + /* callback already freed the chunks */ + return -1; + } + + if (g->verbose) + fprintf (stderr, "receive_file_data_sync: got %d chunks\n", ctx.count); + + /* Process each chunk in the list. */ + if (buf) *buf = NULL; /* Accumulate data in this buffer. */ + len = 0; + + for (i = 0; i < ctx.count; ++i) { + if (ctx.chunks[i].cancel) { + error (g, "file receive cancelled by daemon"); + free_chunks (&ctx); + if (buf) free (*buf); + if (len_r) *len_r = 0; + return -1; + } + + if (ctx.chunks[i].data.data_len == 0) { /* end of transfer */ + free_chunks (&ctx); + if (len_r) *len_r = len; + return 0; + } + + if (buf) { + *buf = safe_realloc (g, *buf, len + ctx.chunks[i].data.data_len); + memcpy (*buf+len, ctx.chunks[i].data.data_val, + ctx.chunks[i].data.data_len); + } + len += ctx.chunks[i].data.data_len; + } + + if (len_r) *len_r = len; + free_chunks (&ctx); + return 1; } -#endif /* This is the default main loop implementation, using select(2). */ @@ -1702,6 +2213,8 @@ select_main_loop_run (guestfs_main_loop *mlv, guestfs_h *g) xset2 = ml->xset; r = select (ml->max_fd+1, &rset2, &wset2, &xset2, NULL); if (r == -1) { + if (errno == EINTR || errno == EAGAIN) + continue; perrorf (g, "select"); ml->is_running = 0; return -1; @@ -1734,10 +2247,9 @@ select_main_loop_quit (guestfs_main_loop *mlv, guestfs_h *g) { struct select_main_loop *ml = (struct select_main_loop *) mlv; - if (!ml->is_running) { - error (g, "cannot quit, we are not running in a main loop"); - return -1; - } + /* Note that legitimately ml->is_running can be zero when + * this function is called. + */ ml->is_running = 0; return 0;