#include <config.h>
#define _BSD_SOURCE /* for mkdtemp, usleep */
+#define _GNU_SOURCE /* for vasprintf, GNU strerror_r */
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <fcntl.h>
+#include <time.h>
#ifdef HAVE_ERRNO_H
#include <errno.h>
#include <sys/un.h>
#endif
+#include <sys/select.h>
+
#include "guestfs.h"
-static int error (guestfs_h *g, const char *fs, ...);
-static int perrorf (guestfs_h *g, const char *fs, ...);
+static void error (guestfs_h *g, const char *fs, ...);
+static void 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);
+static void default_error_cb (guestfs_h *g, void *data, const char *msg);
+static void stdout_event (void *data, int watch, int fd, int events);
+static void sock_read_event (void *data, int watch, int fd, int events);
+//static void sock_write_event (void *data, int watch, int fd, int events);
+
+static int select_add_handle (guestfs_h *g, int fd, int events, guestfs_handle_event_cb cb, void *data);
+static int select_remove_handle (guestfs_h *g, int watch);
+static int select_add_timeout (guestfs_h *g, int interval, guestfs_handle_timeout_cb cb, void *data);
+static int select_remove_timeout (guestfs_h *g, int timer);
+static void select_main_loop_run (guestfs_h *g);
+static void select_main_loop_quit (guestfs_h *g);
+
+#define UNIX_PATH_MAX 108
+
+#define VMCHANNEL_PORT 6666
+#define VMCHANNEL_ADDR "10.0.2.4"
+
+/* Current main loop. */
+static guestfs_main_loop main_loop = {
+ .add_handle = select_add_handle,
+ .remove_handle = select_remove_handle,
+ .add_timeout = select_add_timeout,
+ .remove_timeout = select_remove_timeout,
+ .main_loop_run = select_main_loop_run,
+ .main_loop_quit = select_main_loop_quit,
+};
+
/* GuestFS handle and connection. */
+enum state { CONFIG, LAUNCHING, READY, BUSY, NO_HANDLE };
+
struct guestfs_h
{
- /* All these socks/pids are -1 if not connected. */
+ /* State: see the state machine diagram in the man page guestfs(3). */
+ enum state state;
+
+ int fd[2]; /* Stdin/stdout of qemu. */
int sock; /* Daemon communications socket. */
int pid; /* Qemu PID. */
+ time_t start_t; /* The time when we started qemu. */
+
+ int stdout_watch; /* Watches qemu stdout for log messages. */
+ int sock_watch; /* Watches daemon comm socket. */
- char *tmpdir; /* Temporary directory containing logfile
- * and socket. Cleaned up unless there is
- * an error.
- */
+ char *tmpdir; /* Temporary directory containing socket. */
char **cmdline; /* Qemu command line. */
int cmdline_size;
- guestfs_abort_fn abort_fn;
- int exit_on_error;
int verbose;
+
+ /* Callbacks. */
+ guestfs_abort_cb abort_cb;
+ guestfs_error_handler_cb error_cb;
+ void * error_cb_data;
+ guestfs_reply_cb reply_cb;
+ void * reply_cb_data;
+ guestfs_log_message_cb log_message_cb;
+ void * log_message_cb_data;
+ guestfs_subprocess_quit_cb subprocess_quit_cb;
+ void * subprocess_quit_cb_data;
+ guestfs_launch_done_cb launch_done_cb;
+ void * launch_done_cb_data;
+
+ /* These callbacks are called before reply_cb and launch_done_cb,
+ * and are used to implement the high-level API without needing to
+ * interfere with callbacks that the user might have set.
+ */
+ guestfs_reply_cb reply_cb_internal;
+ void * reply_cb_internal_data;
+ guestfs_launch_done_cb launch_done_cb_internal;
+ void * launch_done_cb_internal_data;
};
guestfs_h *
guestfs_create (void)
{
guestfs_h *g;
+ const char *str;
g = malloc (sizeof (*g));
if (!g) return NULL;
- g->sock = -1;
- g->pid = -1;
+ memset (g, 0, sizeof (*g));
+
+ g->state = CONFIG;
- g->tmpdir = NULL;
+ g->fd[0] = -1;
+ g->fd[1] = -1;
+ g->sock = -1;
+ g->stdout_watch = -1;
+ g->sock_watch = -1;
- g->abort_fn = abort; /* Have to set these before safe_malloc. */
- g->exit_on_error = 0;
- g->verbose = getenv ("LIBGUESTFS_VERBOSE") != NULL;
+ g->abort_cb = abort;
+ g->error_cb = default_error_cb;
+ g->error_cb_data = NULL;
- 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_DEBUG");
+ g->verbose = str != NULL && strcmp (str, "1") == 0;
return g;
}
void
-guestfs_free (guestfs_h *g)
+guestfs_close (guestfs_h *g)
{
int i;
char filename[256];
- if (g->pid) guestfs_kill_subprocess (g);
+ if (g->state == NO_HANDLE) {
+ /* Not safe to call 'error' here, so ... */
+ fprintf (stderr, "guestfs_close: called twice on the same handle\n");
+ return;
+ }
- /* The assumption is that programs calling this have successfully
- * used qemu, so delete the logfile and socket directory.
+ /* 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);
+
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;
free (g);
}
-/* Cleanup fds and sockets, assuming the subprocess is dead already. */
static void
-cleanup_fds (guestfs_h *g)
+default_error_cb (guestfs_h *g, void *data, const char *msg)
{
- if (g->sock >= 0) close (g->sock);
- g->sock = -1;
+ fprintf (stderr, "libguestfs: %s\n", msg);
}
-/* Wait for subprocess to exit. */
static void
-wait_subprocess (guestfs_h *g)
-{
- if (g->pid >= 0) waitpid (g->pid, NULL, 0);
- g->pid = -1;
-}
-
-static int
error (guestfs_h *g, const char *fs, ...)
{
va_list args;
+ char *msg;
+
+ if (!g->error_cb) return;
- fprintf (stderr, "libguestfs: ");
va_start (args, fs);
- vfprintf (stderr, fs, args);
+ vasprintf (&msg, fs, args);
va_end (args);
- fputc ('\n', stderr);
- if (g->exit_on_error) exit (1);
- return -1;
+ g->error_cb (g, g->error_cb_data, msg);
+
+ free (msg);
}
-static int
+static void
perrorf (guestfs_h *g, const char *fs, ...)
{
va_list args;
- char buf[256];
+ char *msg;
int err = errno;
- fprintf (stderr, "libguestfs: ");
+ if (!g->error_cb) return;
+
va_start (args, fs);
- vfprintf (stderr, fs, args);
+ vasprintf (&msg, fs, args);
va_end (args);
+
+#ifndef _GNU_SOURCE
+ char buf[256];
strerror_r (err, buf, sizeof buf);
- fprintf (stderr, ": %s\n", buf);
+#else
+ char _buf[256];
+ char *buf;
+ buf = strerror_r (err, _buf, sizeof _buf);
+#endif
- if (g->exit_on_error) exit (1);
- return -1;
+ msg = safe_realloc (g, msg, strlen (msg) + 2 + strlen (buf) + 1);
+ strcat (msg, ": ");
+ strcat (msg, buf);
+
+ g->error_cb (g, g->error_cb_data, msg);
+
+ free (msg);
}
static void *
safe_malloc (guestfs_h *g, int nbytes)
{
void *ptr = malloc (nbytes);
- if (!ptr) g->abort_fn ();
+ if (!ptr) g->abort_cb ();
return ptr;
}
safe_realloc (guestfs_h *g, void *ptr, int nbytes)
{
void *p = realloc (ptr, nbytes);
- if (!p) g->abort_fn ();
+ if (!p) g->abort_cb ();
return p;
}
safe_strdup (guestfs_h *g, const char *str)
{
char *s = strdup (str);
- if (!s) g->abort_fn ();
+ if (!s) g->abort_cb ();
return s;
}
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
return g->verbose;
}
-/* Add an escaped string to the current command line. */
-static int
-add_cmdline (guestfs_h *g, const char *str)
+/* Add a string to the current command line. */
+static void
+incr_cmdline_size (guestfs_h *g)
{
- if (g->pid >= 0)
- return error (g, "command line cannot be altered after qemu subprocess launched");
+ if (g->cmdline == NULL) {
+ /* g->cmdline[0] is reserved for argv[0], set in guestfs_launch. */
+ g->cmdline_size = 1;
+ g->cmdline = safe_malloc (g, sizeof (char *));
+ g->cmdline[0] = NULL;
+ }
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);
+}
+
+static int
+add_cmdline (guestfs_h *g, const char *str)
+{
+ if (g->state != CONFIG) {
+ error (g, "command line cannot be altered after qemu subprocess launched");
+ return -1;
+ }
+ incr_cmdline_size (g);
+ g->cmdline[g->cmdline_size-1] = safe_strdup (g, str);
return 0;
}
guestfs_config (guestfs_h *g,
const char *qemu_param, const char *qemu_value)
{
- if (qemu_param[0] != '-')
- return error (g, "guestfs_config: parameter must begin with '-' character");
+ if (qemu_param[0] != '-') {
+ error (g, "guestfs_config: parameter must begin with '-' character");
+ return -1;
+ }
/* A bit fascist, but the user will probably break the extra
* parameters that we add if they try to set any of these.
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");
+ strcmp (qemu_param, "-vnc") == 0) {
+ error (g, "guestfs_config: parameter '%s' isn't allowed", qemu_param);
+ return -1;
+ }
if (add_cmdline (g, qemu_param) != 0) return -1;
int len = strlen (filename) + 64;
char buf[len];
- if (strchr (filename, ',') != NULL)
- return error (g, "filename cannot contain ',' (comma) character");
+ if (strchr (filename, ',') != NULL) {
+ error (g, "filename cannot contain ',' (comma) character");
+ return -1;
+ }
- snprintf (buf, len, "file=%s,media=disk", filename);
+ snprintf (buf, len, "file=%s", filename);
return guestfs_config (g, "-drive", buf);
}
int
guestfs_add_cdrom (guestfs_h *g, const char *filename)
{
- int len = strlen (filename) + 64;
- char buf[len];
-
- if (strchr (filename, ',') != NULL)
- return error (g, "filename cannot contain ',' (comma) character");
-
- snprintf (buf, len, "file=%s,if=ide,index=1,media=cdrom", filename);
+ if (strchr (filename, ',') != NULL) {
+ error (g, "filename cannot contain ',' (comma) character");
+ return -1;
+ }
- return guestfs_config (g, "-drive", buf);
+ return guestfs_config (g, "-cdrom", filename);
}
int
{
static const char *dir_template = "/tmp/libguestfsXXXXXX";
int r, i;
- const char *qemu = QEMU; /* XXX */
- const char *kernel = "/boot/vmlinuz-2.6.27.15-170.2.24.fc10.x86_64";
- const char *initrd = "/boot/initrd-2.6.27.15-170.2.24.fc10.x86_64.img";
+ int wfd[2], rfd[2];
+ int tries;
+ /*const char *qemu = QEMU;*/ /* XXX */
+ const char *qemu = "/usr/bin/qemu-system-x86_64";
+ const char *kernel = "vmlinuz.fedora-10.x86_64";
+ const char *initrd = "initramfs.fedora-10.x86_64.img";
char unixsock[256];
- char vmchannel[256];
- char tmpfile[256];
+ struct sockaddr_un addr;
/* XXX Choose which qemu to run. */
/* XXX Choose initrd, etc. */
- /* Make the temporary directory containing the logfile and socket. */
+ /* Configured? */
+ if (!g->cmdline) {
+ error (g, "you must call guestfs_add_drive before guestfs_launch");
+ return -1;
+ }
+
+ if (g->state != CONFIG) {
+ error (g, "qemu has already been launched");
+ return -1;
+ }
+
+ /* Make the temporary directory containing the 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);
+ if (mkdtemp (g->tmpdir) == NULL) {
+ perrorf (g, "%s: cannot create temporary directory", dir_template);
+ return -1;
+ }
+ }
+
+ snprintf (unixsock, sizeof unixsock, "%s/sock", g->tmpdir);
- snprintf (unixsock, sizeof unixsock, "%s/sock", g->tmpdir);
+ if (pipe (wfd) == -1 || pipe (rfd) == -1) {
+ perrorf (g, "pipe");
+ return -1;
}
r = fork ();
- if (r == -1)
- return perrorf (g, "fork");
+ if (r == -1) {
+ perrorf (g, "fork");
+ close (wfd[0]);
+ close (wfd[1]);
+ close (rfd[0]);
+ close (rfd[1]);
+ return -1;
+ }
- if (r > 0) { /* Parent (library). */
- g->pid = r;
+ if (r == 0) { /* Child (qemu). */
+ char vmchannel[256];
+ char append[256];
- /* If qemu is going to die during startup, give it a tiny amount of
- * time to print the error message.
- */
- usleep (10000);
- } else { /* Child (qemu). */
/* 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 + 14));
- 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", 666, unixsock);
-
- 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] = "console=ttyS0";
- 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,vlan0";
- g->cmdline[g->cmdline_size+13] = NULL;
+ "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);
+
+ add_cmdline (g, "-m");
+ add_cmdline (g, "384"); /* XXX Choose best size. */
+ add_cmdline (g, "-kernel");
+ add_cmdline (g, (char *) kernel);
+ add_cmdline (g, "-initrd");
+ add_cmdline (g, (char *) initrd);
+ add_cmdline (g, "-append");
+ add_cmdline (g, append);
+ add_cmdline (g, "-nographic");
+ add_cmdline (g, "-serial");
+ add_cmdline (g, "stdio");
+ add_cmdline (g, "-net");
+ add_cmdline (g, vmchannel);
+ add_cmdline (g, "-net");
+ add_cmdline (g, "user,vlan=0");
+ add_cmdline (g, "-net");
+ add_cmdline (g, "nic,vlan=0");
+ incr_cmdline_size (g);
+ g->cmdline[g->cmdline_size-1] = NULL;
if (g->verbose) {
- fprintf (stderr, "Running %s", qemu);
+ fprintf (stderr, "%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. */
+ /* Set up stdin, stdout. */
close (0);
close (1);
- open ("/dev/null", O_RDONLY);
- snprintf (tmpfile, sizeof tmpfile, "%s/qemu.log", g->tmpdir);
- open (tmpfile, O_WRONLY|O_CREAT|O_APPEND, 0644);
- /*dup2 (1, 2);*/
+ close (wfd[1]);
+ close (rfd[0]);
+ dup (wfd[0]);
+ dup (rfd[1]);
+
+#if 0
+ /* 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);
+#endif
execv (qemu, g->cmdline); /* Run qemu. */
perror (qemu);
_exit (1);
}
+ /* Parent (library). */
+ g->pid = r;
+
+ /* Start the clock ... */
+ time (&g->start_t);
+
+ /* Close the other ends of the pipe. */
+ close (wfd[0]);
+ close (rfd[1]);
+
+ if (fcntl (wfd[1], F_SETFL, O_NONBLOCK) == -1 ||
+ fcntl (rfd[0], F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
+ goto cleanup1;
+ }
+
+ g->fd[0] = wfd[1]; /* stdin of child */
+ g->fd[1] = rfd[0]; /* stdout of child */
+
+ /* Open the Unix socket. The vmchannel implementation that got
+ * merged with qemu sucks in a number of ways. Both ends do
+ * connect(2), which means that no one knows what, if anything, is
+ * connected to the other end, or if it becomes disconnected. Even
+ * worse, we have to wait some indeterminate time for qemu to create
+ * the socket and connect to it (which happens very early in qemu's
+ * start-up), so any code that uses vmchannel is inherently racy.
+ * Hence this silly loop.
+ */
+ g->sock = socket (AF_UNIX, SOCK_STREAM, 0);
+ if (g->sock == -1) {
+ perrorf (g, "socket");
+ goto cleanup1;
+ }
+
+ if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
+ goto cleanup2;
+ }
+
+ addr.sun_family = AF_UNIX;
+ strncpy (addr.sun_path, unixsock, UNIX_PATH_MAX);
+ addr.sun_path[UNIX_PATH_MAX-1] = '\0';
+
+ tries = 100;
+ 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;
+
+ perrorf (g, "connect");
+ tries--;
+ }
+
+ error (g, "failed to connect to vmchannel socket");
+ goto cleanup2;
+
+ connected:
+ /* Watch the file descriptors. */
+ g->stdout_watch =
+ main_loop.add_handle (g, g->fd[1],
+ GUESTFS_HANDLE_READABLE,
+ stdout_event, g);
+ if (g->stdout_watch == -1) {
+ error (g, "could not watch qemu stdout");
+ goto cleanup3;
+ }
+
+ g->sock_watch =
+ main_loop.add_handle (g, g->sock,
+ GUESTFS_HANDLE_READABLE |
+ GUESTFS_HANDLE_HANGUP |
+ GUESTFS_HANDLE_ERROR,
+ sock_read_event, g);
+ if (g->sock_watch == -1) {
+ error (g, "could not watch daemon communications socket");
+ goto cleanup3;
+ }
+
+ g->state = LAUNCHING;
return 0;
+
+ cleanup3:
+ if (g->stdout_watch >= 0)
+ main_loop.remove_handle (g, g->stdout_watch);
+ if (g->sock_watch >= 0)
+ main_loop.remove_handle (g, g->sock_watch);
+
+ cleanup2:
+ close (g->sock);
+
+ cleanup1:
+ close (wfd[1]);
+ close (rfd[0]);
+ kill (g->pid, 9);
+ waitpid (g->pid, NULL, 0);
+ 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;
+ return -1;
}
-#define UNIX_PATH_MAX 108
+static void
+finish_wait_ready (guestfs_h *g, void *vp)
+{
+ *((int *)vp) = 1;
+ main_loop.main_loop_quit (g);
+}
int
guestfs_wait_ready (guestfs_h *g)
{
- int r, i, lsock;
- struct sockaddr_un addr;
+ int r = 0;
- if (guestfs_ready (g)) return 0;
+ if (g->state == READY) return 0;
- /* Launch the subprocess, if there isn't one already. */
- if (g->pid == -1) {
- if (guestfs_launch (g) != 0)
- return -1;
+ if (g->state == BUSY) {
+ error (g, "qemu has finished launching already");
+ return -1;
+ }
+
+ if (g->state != LAUNCHING) {
+ error (g, "qemu has not been launched yet");
+ return -1;
}
- if (g->sock >= 0) {
+ g->launch_done_cb_internal = finish_wait_ready;
+ g->launch_done_cb_internal_data = &r;
+ main_loop.main_loop_run (g);
+ g->launch_done_cb_internal = NULL;
+ g->launch_done_cb_internal_data = NULL;
+
+ if (r != 1) {
+ error (g, "guestfs_wait_ready failed, see earlier error messages");
+ return -1;
+ }
+
+ /* This is possible in some really strange situations, such as
+ * guestfsd starts up OK but then qemu immediately exits. Check for
+ * it because the caller is probably expecting to be able to send
+ * commands after this function returns.
+ */
+ if (g->state != READY) {
+ error (g, "qemu launched and contacted daemon, but state != READY");
+ return -1;
+ }
+
+ return 0;
+}
+
+int
+guestfs_kill_subprocess (guestfs_h *g)
+{
+ if (g->state == CONFIG) {
+ error (g, "no subprocess to kill");
+ return -1;
+ }
+
+ if (g->verbose)
+ fprintf (stderr, "sending SIGTERM to process group %d\n", g->pid);
+
+ kill (g->pid, SIGTERM);
+
+ return 0;
+}
+
+/* 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.
+ */
+static void
+stdout_event (void *data, int watch, int fd, int events)
+{
+ guestfs_h *g = (guestfs_h *) data;
+ char buf[4096];
+ int n;
+
+#if 0
+ if (g->verbose)
+ fprintf (stderr,
+ "stdout_event: %p g->state = %d, fd = %d, events = 0x%x\n",
+ g, g->state, fd, events);
+#endif
+
+ if (g->fd[1] != fd) {
+ error (g, "stdout_event: internal error: %d != %d", g->fd[1], fd);
+ return;
+ }
+
+ 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)
+ main_loop.remove_handle (g, g->stdout_watch);
+ if (g->sock_watch >= 0)
+ main_loop.remove_handle (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);
+ return;
}
- lsock = socket (AF_UNIX, SOCK_STREAM, 0);
- if (lsock == -1)
- return perrorf (g, "socket");
+ if (n == -1) {
+ if (errno != EAGAIN)
+ perrorf (g, "read");
+ return;
+ }
- addr.sun_family = AF_UNIX;
- snprintf (addr.sun_path, UNIX_PATH_MAX, "%s/sock", g->tmpdir);
+ /* In verbose mode, copy all log messages to stderr. */
+ if (g->verbose)
+ write (2, buf, n);
+
+ /* It's an actual log message, send it upwards if anyone is listening. */
+ if (g->log_message_cb)
+ g->log_message_cb (g, g->log_message_cb_data, buf, n);
+}
+
+/* The function is called whenever we can read something on the
+ * guestfsd (daemon inside the guest) communication socket.
+ */
+static void
+sock_read_event (void *data, int watch, int fd, int events)
+{
+ /*guestfs_h *g = (guestfs_h *) data;*/
+
+
+
+
+
+
+
+}
+
+/* This is the default main loop implementation, using select(2). */
+
+struct handle_cb_data {
+ guestfs_handle_event_cb cb;
+ void *data;
+};
- if (bind (lsock, (struct sockaddr *) &addr, sizeof addr) == -1) {
- perrorf (g, "bind");
- close (lsock);
+static fd_set rset;
+static fd_set wset;
+static fd_set xset;
+static int select_init_done = 0;
+static int max_fd = -1;
+static struct handle_cb_data *handle_cb_data = NULL;
+
+static void
+select_init (void)
+{
+ if (!select_init_done) {
+ FD_ZERO (&rset);
+ FD_ZERO (&wset);
+ FD_ZERO (&xset);
+
+ select_init_done = 1;
+ }
+}
+
+static int
+select_add_handle (guestfs_h *g, int fd, int events,
+ guestfs_handle_event_cb cb, void *data)
+{
+ select_init ();
+
+ if (fd < 0 || fd >= FD_SETSIZE) {
+ error (g, "fd %d is out of range", fd);
return -1;
}
- if (listen (lsock, 1) == -1) {
- perrorf (g, "listen");
- close (lsock);
+ if ((events & ~(GUESTFS_HANDLE_READABLE |
+ GUESTFS_HANDLE_WRITABLE |
+ GUESTFS_HANDLE_HANGUP |
+ GUESTFS_HANDLE_ERROR)) != 0) {
+ error (g, "set of events (0x%x) contains unknown events", events);
return -1;
}
- if (fcntl (lsock, F_SETFL, O_NONBLOCK) == -1) {
- perrorf (g, "set socket non-blocking");
- close (lsock);
+ if (events == 0) {
+ error (g, "set of events is empty");
return -1;
}
- /* Wait until the daemon running inside the guest connects to the
- * Unix socket, which indicates it's alive. Qemu might exit in the
- * meantime if there is a problem. More problematically qemu might
- * hang, which we can only detect by timeout.
- */
- for (i = 0; i < 30; ++i) {
- r = waitpid (g->pid, NULL, WNOHANG);
-
- if (r > 0 || (r == -1 && errno == ECHILD)) {
- error (g, "qemu subprocess exited unexpectedly during initialization");
- g->pid = -1;
- cleanup_fds (g);
- close (lsock);
- return -1;
- }
+ if (FD_ISSET (fd, &rset) || FD_ISSET (fd, &wset) || FD_ISSET (fd, &xset)) {
+ error (g, "fd %d is already registered", fd);
+ return -1;
+ }
- r = accept (lsock, NULL, 0);
- if (r >= 0) {
- g->sock = r;
- fcntl (g->sock, F_SETFL, O_NONBLOCK);
- close (lsock);
- return 0;
- }
- if (errno == EAGAIN) {
- sleep (1);
- continue;
- }
- perrorf (g, "accept");
- close (lsock);
- guestfs_kill_subprocess (g);
+ if (cb == NULL) {
+ error (g, "callback is NULL");
return -1;
}
- close (lsock);
- return error (g, "timeout waiting for guest to become ready");
+ if ((events & GUESTFS_HANDLE_READABLE))
+ FD_SET (fd, &rset);
+ if ((events & GUESTFS_HANDLE_WRITABLE))
+ FD_SET (fd, &wset);
+ if ((events & GUESTFS_HANDLE_HANGUP) || (events & GUESTFS_HANDLE_ERROR))
+ FD_SET (fd, &xset);
+
+ if (fd > max_fd) {
+ max_fd = fd;
+ handle_cb_data = safe_realloc (g, handle_cb_data,
+ sizeof (struct handle_cb_data) * (max_fd+1));
+ }
+ handle_cb_data[fd].cb = cb;
+ handle_cb_data[fd].data = data;
+
+ /* Any integer >= 0 can be the handle, and this is as good as any ... */
+ return fd;
}
-int
-guestfs_ready (guestfs_h *g)
+static int
+select_remove_handle (guestfs_h *g, int fd)
+{
+ select_init ();
+
+ if (fd < 0 || fd >= FD_SETSIZE) {
+ error (g, "fd %d is out of range", fd);
+ return -1;
+ }
+
+ if (!FD_ISSET (fd, &rset) && !FD_ISSET (fd, &wset) && !FD_ISSET (fd, &xset)) {
+ error (g, "fd %d was not registered", fd);
+ return -1;
+ }
+
+ FD_CLR (fd, &rset);
+ FD_CLR (fd, &wset);
+ FD_CLR (fd, &xset);
+
+ if (fd == max_fd) {
+ max_fd--;
+ handle_cb_data = safe_realloc (g, handle_cb_data,
+ sizeof (struct handle_cb_data) * (max_fd+1));
+ }
+
+ return 0;
+}
+
+static int
+select_add_timeout (guestfs_h *g, int interval,
+ guestfs_handle_timeout_cb cb, void *data)
{
- return
- g->pid >= 0 &&
- kill (g->pid, 0) == 0 &&
- g->sock >= 0 /* &&
- guestfs_ping_daemon (g) >= 0 */;
+ select_init ();
+
+ abort (); /* XXX not implemented yet */
}
-int
-guestfs_kill_subprocess (guestfs_h *g)
+static int
+select_remove_timeout (guestfs_h *g, int timer)
{
- if (g->pid >= 0) {
- if (g->verbose)
- fprintf (stderr, "sending SIGINT to pid %d\n", g->pid);
+ select_init ();
- kill (g->pid, SIGINT);
- wait_subprocess (g);
+ abort (); /* XXX not implemented yet */
+}
+
+/* Note that main loops can be nested. */
+static int level = 0;
+
+static void
+select_main_loop_run (guestfs_h *g)
+{
+ int old_level, fd, r, events;
+ fd_set rset2, wset2, xset2;
+
+ select_init ();
+
+ old_level = level++;
+ while (level > old_level) {
+ rset2 = rset;
+ wset2 = wset;
+ xset2 = xset;
+ r = select (max_fd+1, &rset2, &wset2, &xset2, NULL);
+ if (r == -1) {
+ perrorf (g, "select");
+ level = old_level;
+ break;
+ }
+
+ for (fd = 0; r > 0 && fd <= max_fd; ++fd) {
+ events = 0;
+ if (FD_ISSET (fd, &rset2))
+ events |= GUESTFS_HANDLE_READABLE;
+ if (FD_ISSET (fd, &wset2))
+ events |= GUESTFS_HANDLE_WRITABLE;
+ if (FD_ISSET (fd, &xset2))
+ events |= GUESTFS_HANDLE_ERROR | GUESTFS_HANDLE_HANGUP;
+ if (events) {
+ r--;
+ handle_cb_data[fd].cb (handle_cb_data[fd].data,
+ fd, fd, events);
+ }
+ }
}
+}
- cleanup_fds (g);
+static void
+select_main_loop_quit (guestfs_h *g)
+{
+ select_init ();
- return 0;
+ if (level == 0) {
+ error (g, "cannot quit, we are not in a main loop");
+ return;
+ }
+
+ level--;
}
git.annexia.org / libguestfs.git / blobdiff