/* libguestfs
- * Copyright (C) 2009 Red Hat Inc.
+ * Copyright (C) 2009 Red Hat Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
#include <config.h>
#define _BSD_SOURCE /* for mkdtemp, usleep */
-#define _GNU_SOURCE /* for vasprintf, GNU strerror_r, strchrnul */
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
+#include <stddef.h>
#include <unistd.h>
#include <ctype.h>
#include <string.h>
#include <fcntl.h>
#include <time.h>
+#include <sys/stat.h>
#include <sys/select.h>
+#include <dirent.h>
+
#include <rpc/types.h>
#include <rpc/xdr.h>
#include <sys/un.h>
#endif
+#include <arpa/inet.h>
+#include <netinet/in.h>
+
#include "guestfs.h"
+#include "guestfs-internal-actions.h"
#include "guestfs_protocol.h"
+#include "ignore-value.h"
+
+#ifdef HAVE_GETTEXT
+#include "gettext.h"
+#define _(str) dgettext(PACKAGE, (str))
+//#define N_(str) dgettext(PACKAGE, (str))
+#else
+#define _(str) str
+//#define N_(str) str
+#endif
-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);
+#define error guestfs_error
+#define perrorf guestfs_perrorf
+#define safe_malloc guestfs_safe_malloc
+#define safe_realloc guestfs_safe_realloc
+#define safe_strdup guestfs_safe_strdup
+//#define safe_memdup guestfs_safe_memdup
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 send_to_daemon (guestfs_h *g, const void *v_buf, size_t n);
+static int recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn);
+static int accept_from_daemon (guestfs_h *g);
+static int check_peer_euid (guestfs_h *g, int sock, uid_t *rtn);
static void close_handles (void);
-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
/* Also in guestfsd.c */
-#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,
-};
+#define GUESTFWD_ADDR "10.0.2.4"
+#define GUESTFWD_PORT "6666"
/* GuestFS handle and connection. */
enum state { CONFIG, LAUNCHING, READY, BUSY, NO_HANDLE };
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. */
- int sock_watch; /* Watches daemon comm socket. */
-
char *tmpdir; /* Temporary directory containing socket. */
+ char *qemu_help, *qemu_version; /* Output of qemu -help, qemu -version. */
+
char **cmdline; /* Qemu command line. */
int cmdline_size;
int verbose;
+ int trace;
int autosync;
- const char *path;
+ char *path; /* Path to kernel, initrd. */
+ char *qemu; /* Qemu binary. */
+ char *append; /* Append to kernel command line. */
+
+ int memsize; /* Size of RAM (megabytes). */
+
+ int selinux; /* selinux enabled? */
+
+ char *last_error;
/* 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;
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;
-
- /* Messages sent and received from the daemon. */
- char *msg_in;
- int msg_in_size, msg_in_allocated;
- char *msg_out;
- int msg_out_size, msg_out_pos;
-
int msg_next_serial;
};
g->fd[0] = -1;
g->fd[1] = -1;
g->sock = -1;
- g->stdout_watch = -1;
- g->sock_watch = -1;
g->abort_cb = abort;
g->error_cb = default_error_cb;
str = getenv ("LIBGUESTFS_DEBUG");
g->verbose = str != NULL && strcmp (str, "1") == 0;
+ str = getenv ("LIBGUESTFS_TRACE");
+ g->trace = 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;
+ }
+
+ /* Choose a suitable memory size. Previously we tried to choose
+ * a minimal memory size, but this isn't really necessary since
+ * recent QEMU and KVM don't do anything nasty like locking
+ * memory into core any more. Thus we can safely choose a
+ * large, generous amount of memory, and it'll just get swapped
+ * on smaller systems.
+ */
+ str = getenv ("LIBGUESTFS_MEMSIZE");
+ if (str) {
+ if (sscanf (str, "%d", &g->memsize) != 1 || g->memsize <= 256) {
+ fprintf (stderr, "libguestfs: non-numeric or too small value for LIBGUESTFS_MEMSIZE\n");
+ goto error;
+ }
+ } else
+ g->memsize = 500;
/* Start with large serial numbers so they are easy to spot
* inside the protocol.
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
if (g->state == NO_HANDLE) {
/* Not safe to call 'error' here, so ... */
- fprintf (stderr, "guestfs_close: called twice on the same handle\n");
+ fprintf (stderr, _("guestfs_close: called twice on the same handle\n"));
return;
}
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.
if (g->state != CONFIG)
guestfs_kill_subprocess (g);
+ /* Close sockets. */
+ if (g->fd[0] >= 0)
+ close (g->fd[0]);
+ if (g->fd[1] >= 0)
+ close (g->fd[1]);
+ if (g->sock >= 0)
+ close (g->sock);
+ g->fd[0] = -1;
+ g->fd[1] = -1;
+ g->sock = -1;
+
+ /* Wait for subprocess(es) to exit. */
+ waitpid (g->pid, NULL, 0);
+ if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0);
+
+ /* Remove tmpfiles. */
if (g->tmpdir) {
snprintf (filename, sizeof filename, "%s/sock", g->tmpdir);
unlink (filename);
+ snprintf (filename, sizeof filename, "%s/initrd", g->tmpdir);
+ unlink (filename);
+
+ snprintf (filename, sizeof filename, "%s/kernel", g->tmpdir);
+ unlink (filename);
+
rmdir (g->tmpdir);
free (g->tmpdir);
}
/* release mutex (XXX) */
+ free (g->last_error);
+ free (g->path);
+ free (g->qemu);
+ free (g->append);
+ free (g->qemu_help);
+ free (g->qemu_version);
free (g);
}
while (handles) guestfs_close (handles);
}
+const char *
+guestfs_last_error (guestfs_h *g)
+{
+ return g->last_error;
+}
+
static void
-default_error_cb (guestfs_h *g, void *data, const char *msg)
+set_last_error (guestfs_h *g, const char *msg)
{
- fprintf (stderr, "libguestfs: error: %s\n", msg);
+ free (g->last_error);
+ g->last_error = strdup (msg);
}
static void
-error (guestfs_h *g, const char *fs, ...)
+default_error_cb (guestfs_h *g, void *data, const char *msg)
+{
+ fprintf (stderr, _("libguestfs: error: %s\n"), msg);
+}
+
+void
+guestfs_error (guestfs_h *g, const char *fs, ...)
{
va_list args;
char *msg;
- if (!g->error_cb) return;
-
va_start (args, fs);
- vasprintf (&msg, fs, args);
+ int err = vasprintf (&msg, fs, args);
va_end (args);
- g->error_cb (g, g->error_cb_data, msg);
+ if (err < 0) return;
+
+ if (g->error_cb) g->error_cb (g, g->error_cb_data, msg);
+ set_last_error (g, msg);
free (msg);
}
-static void
-perrorf (guestfs_h *g, const char *fs, ...)
+void
+guestfs_perrorf (guestfs_h *g, const char *fs, ...)
{
va_list args;
char *msg;
- int err = errno;
-
- if (!g->error_cb) return;
+ int errnum = errno;
va_start (args, fs);
- vasprintf (&msg, fs, args);
+ int err = vasprintf (&msg, fs, args);
va_end (args);
+ if (err < 0) return;
+
#ifndef _GNU_SOURCE
char buf[256];
- strerror_r (err, buf, sizeof buf);
+ strerror_r (errnum, buf, sizeof buf);
#else
char _buf[256];
char *buf;
- buf = strerror_r (err, _buf, sizeof _buf);
+ buf = strerror_r (errnum, _buf, sizeof _buf);
#endif
msg = safe_realloc (g, msg, strlen (msg) + 2 + strlen (buf) + 1);
strcat (msg, ": ");
strcat (msg, buf);
- g->error_cb (g, g->error_cb_data, msg);
+ if (g->error_cb) g->error_cb (g, g->error_cb_data, msg);
+ set_last_error (g, msg);
free (msg);
}
-static void *
-safe_malloc (guestfs_h *g, int nbytes)
+void *
+guestfs_safe_malloc (guestfs_h *g, size_t nbytes)
{
void *ptr = malloc (nbytes);
- if (!ptr) g->abort_cb ();
+ if (nbytes > 0 && !ptr) g->abort_cb ();
return ptr;
}
-static void *
-safe_realloc (guestfs_h *g, void *ptr, int nbytes)
+/* Return 1 if an array of N objects, each of size S, cannot exist due
+ to size arithmetic overflow. S must be positive and N must be
+ nonnegative. This is a macro, not an inline function, so that it
+ works correctly even when SIZE_MAX < N.
+
+ By gnulib convention, SIZE_MAX represents overflow in size
+ calculations, so the conservative dividend to use here is
+ SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
+ However, malloc (SIZE_MAX) fails on all known hosts where
+ sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
+ exactly-SIZE_MAX allocations on such hosts; this avoids a test and
+ branch when S is known to be 1. */
+# define xalloc_oversized(n, s) \
+ ((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
+
+/* Technically we should add an autoconf test for this, testing for the desired
+ functionality, like what's done in gnulib, but for now, this is fine. */
+#define HAVE_GNU_CALLOC (__GLIBC__ >= 2)
+
+/* Allocate zeroed memory for N elements of S bytes, with error
+ checking. S must be nonzero. */
+void *
+guestfs_safe_calloc (guestfs_h *g, size_t n, size_t s)
+{
+ /* From gnulib's calloc function in xmalloc.c. */
+ void *p;
+ /* Test for overflow, since some calloc implementations don't have
+ proper overflow checks. But omit overflow and size-zero tests if
+ HAVE_GNU_CALLOC, since GNU calloc catches overflow and never
+ returns NULL if successful. */
+ if ((! HAVE_GNU_CALLOC && xalloc_oversized (n, s))
+ || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0)))
+ g->abort_cb ();
+ return p;
+}
+
+void *
+guestfs_safe_realloc (guestfs_h *g, void *ptr, int nbytes)
{
void *p = realloc (ptr, nbytes);
- if (!p) g->abort_cb ();
+ if (nbytes > 0 && !p) g->abort_cb ();
return p;
}
-static char *
-safe_strdup (guestfs_h *g, const char *str)
+char *
+guestfs_safe_strdup (guestfs_h *g, const char *str)
{
char *s = strdup (str);
if (!s) g->abort_cb ();
return s;
}
+void *
+guestfs_safe_memdup (guestfs_h *g, void *ptr, size_t size)
+{
+ void *p = malloc (size);
+ if (!p) g->abort_cb ();
+ memcpy (p, ptr, size);
+ return p;
+}
+
+static int
+xwrite (int fd, const void *v_buf, size_t len)
+{
+ const char *buf = v_buf;
+ int r;
+
+ while (len > 0) {
+ r = write (fd, buf, len);
+ if (r == -1)
+ return -1;
+
+ buf += r;
+ len -= r;
+ }
+
+ return 0;
+}
+
void
guestfs_set_out_of_memory_handler (guestfs_h *g, guestfs_abort_cb cb)
{
return g->error_cb;
}
-void
-guestfs_set_verbose (guestfs_h *g, int v)
+int
+guestfs__set_verbose (guestfs_h *g, int v)
{
- g->verbose = v;
+ g->verbose = !!v;
+ return 0;
}
int
-guestfs_get_verbose (guestfs_h *g)
+guestfs__get_verbose (guestfs_h *g)
{
return g->verbose;
}
-void
-guestfs_set_autosync (guestfs_h *g, int a)
+int
+guestfs__set_autosync (guestfs_h *g, int a)
{
- g->autosync = a;
+ g->autosync = !!a;
+ return 0;
}
int
-guestfs_get_autosync (guestfs_h *g)
+guestfs__get_autosync (guestfs_h *g)
{
return g->autosync;
}
-void
-guestfs_set_path (guestfs_h *g, const char *path)
+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;
}
const char *
-guestfs_get_path (guestfs_h *g)
+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;
+}
+
+int
+guestfs__set_memsize (guestfs_h *g, int memsize)
+{
+ g->memsize = memsize;
+ return 0;
+}
+
+int
+guestfs__get_memsize (guestfs_h *g)
+{
+ return g->memsize;
+}
+
+int
+guestfs__set_selinux (guestfs_h *g, int selinux)
+{
+ g->selinux = selinux;
+ return 0;
+}
+
+int
+guestfs__get_selinux (guestfs_h *g)
+{
+ return g->selinux;
+}
+
+int
+guestfs__get_pid (guestfs_h *g)
+{
+ if (g->pid > 0)
+ return g->pid;
+ else {
+ error (g, "get_pid: no qemu subprocess");
+ return -1;
+ }
+}
+
+struct guestfs_version *
+guestfs__version (guestfs_h *g)
+{
+ struct guestfs_version *r;
+
+ r = safe_malloc (g, sizeof *r);
+ r->major = PACKAGE_VERSION_MAJOR;
+ r->minor = PACKAGE_VERSION_MINOR;
+ r->release = PACKAGE_VERSION_RELEASE;
+ r->extra = safe_strdup (g, PACKAGE_VERSION_EXTRA);
+ return r;
+}
+
+int
+guestfs__set_trace (guestfs_h *g, int t)
+{
+ g->trace = !!t;
+ return 0;
+}
+
+int
+guestfs__get_trace (guestfs_h *g)
+{
+ return g->trace;
+}
+
/* Add a string to the current command line. */
static void
incr_cmdline_size (guestfs_h *g)
add_cmdline (guestfs_h *g, const char *str)
{
if (g->state != CONFIG) {
- error (g, "command line cannot be altered after qemu subprocess launched");
+ error (g,
+ _("command line cannot be altered after qemu subprocess launched"));
return -1;
}
}
int
-guestfs_config (guestfs_h *g,
- const char *qemu_param, const char *qemu_value)
+guestfs__config (guestfs_h *g,
+ const char *qemu_param, const char *qemu_value)
{
if (qemu_param[0] != '-') {
- error (g, "guestfs_config: parameter must begin with '-' character");
+ error (g, _("guestfs_config: parameter must begin with '-' character"));
return -1;
}
strcmp (qemu_param, "-initrd") == 0 ||
strcmp (qemu_param, "-nographic") == 0 ||
strcmp (qemu_param, "-serial") == 0 ||
- strcmp (qemu_param, "-vnc") == 0 ||
strcmp (qemu_param, "-full-screen") == 0 ||
strcmp (qemu_param, "-std-vga") == 0 ||
strcmp (qemu_param, "-vnc") == 0) {
- error (g, "guestfs_config: parameter '%s' isn't allowed", qemu_param);
+ error (g, _("guestfs_config: parameter '%s' isn't allowed"), qemu_param);
return -1;
}
}
int
-guestfs_add_drive (guestfs_h *g, const char *filename)
+guestfs__add_drive (guestfs_h *g, const char *filename)
+{
+ size_t len = strlen (filename) + 64;
+ char buf[len];
+
+ if (strchr (filename, ',') != NULL) {
+ error (g, _("filename cannot contain ',' (comma) character"));
+ return -1;
+ }
+
+ /* cache=off improves reliability in the event of a host crash.
+ *
+ * However this option causes qemu to try to open the file with
+ * O_DIRECT. This fails on some filesystem types (notably tmpfs).
+ * So we check if we can open the file with or without O_DIRECT,
+ * and use cache=off (or not) accordingly.
+ *
+ * This test also checks for the presence of the file, which
+ * is a documented semantic of this interface.
+ */
+ int fd = open (filename, O_RDONLY|O_DIRECT);
+ if (fd >= 0) {
+ close (fd);
+ snprintf (buf, len, "file=%s,cache=off,if=" DRIVE_IF, filename);
+ } else {
+ fd = open (filename, O_RDONLY);
+ if (fd >= 0) {
+ close (fd);
+ snprintf (buf, len, "file=%s,if=" DRIVE_IF, filename);
+ } else {
+ perrorf (g, "%s", filename);
+ return -1;
+ }
+ }
+
+ return guestfs__config (g, "-drive", buf);
+}
+
+int
+guestfs__add_drive_ro (guestfs_h *g, const char *filename)
{
- int len = strlen (filename) + 64;
+ size_t len = strlen (filename) + 64;
char buf[len];
if (strchr (filename, ',') != NULL) {
- error (g, "filename cannot contain ',' (comma) character");
+ error (g, _("filename cannot contain ',' (comma) character"));
+ return -1;
+ }
+
+ if (access (filename, F_OK) == -1) {
+ perrorf (g, "%s", filename);
return -1;
}
- snprintf (buf, len, "file=%s", filename);
+ snprintf (buf, len, "file=%s,snapshot=on,if=%s", filename, DRIVE_IF);
- return guestfs_config (g, "-drive", buf);
+ return guestfs__config (g, "-drive", buf);
}
int
-guestfs_add_cdrom (guestfs_h *g, const char *filename)
+guestfs__add_cdrom (guestfs_h *g, const char *filename)
{
if (strchr (filename, ',') != NULL) {
- error (g, "filename cannot contain ',' (comma) character");
+ error (g, _("filename cannot contain ',' (comma) character"));
+ return -1;
+ }
+
+ if (access (filename, F_OK) == -1) {
+ perrorf (g, "%s", filename);
return -1;
}
- return guestfs_config (g, "-cdrom", filename);
+ return guestfs__config (g, "-cdrom", filename);
+}
+
+/* Returns true iff file is contained in dir. */
+static int
+dir_contains_file (const char *dir, const char *file)
+{
+ int dirlen = strlen (dir);
+ int filelen = strlen (file);
+ int len = dirlen+filelen+2;
+ char path[len];
+
+ snprintf (path, len, "%s/%s", dir, file);
+ return access (path, F_OK) == 0;
+}
+
+/* Returns true iff every listed file is contained in 'dir'. */
+static int
+dir_contains_files (const char *dir, ...)
+{
+ va_list args;
+ const char *file;
+
+ va_start (args, dir);
+ while ((file = va_arg (args, const char *)) != NULL) {
+ if (!dir_contains_file (dir, file)) {
+ va_end (args);
+ return 0;
+ }
+ }
+ va_end (args);
+ return 1;
}
+static int build_supermin_appliance (guestfs_h *g, const char *path, char **kernel, char **initrd);
+static int test_qemu (guestfs_h *g);
+static int qemu_supports (guestfs_h *g, const char *option);
+static void print_cmdline (guestfs_h *g);
+
+static const char *kernel_name = "vmlinuz." REPO "." host_cpu;
+static const char *initrd_name = "initramfs." REPO "." host_cpu ".img";
+static const char *supermin_name =
+ "initramfs." REPO "." host_cpu ".supermin.img";
+static const char *supermin_hostfiles_name =
+ "initramfs." REPO "." host_cpu ".supermin.hostfiles";
+
int
-guestfs_launch (guestfs_h *g)
+guestfs__launch (guestfs_h *g)
{
- static const char *dir_template = "/tmp/libguestfsXXXXXX";
- int r, i, len, pmore;
+ const char *tmpdir;
+ char dir_template[PATH_MAX];
+ int r, pmore;
+ size_t len;
int wfd[2], rfd[2];
int tries;
- const char *kernel_name = "vmlinuz." REPO "." host_cpu;
- const char *initrd_name = "initramfs." REPO "." host_cpu ".img";
char *path, *pelem, *pend;
char *kernel = NULL, *initrd = NULL;
+ int null_vmchannel_sock;
char unixsock[256];
struct sockaddr_un addr;
+#ifdef P_tmpdir
+ tmpdir = P_tmpdir;
+#else
+ tmpdir = "/tmp";
+#endif
+
+ tmpdir = getenv ("TMPDIR") ? : tmpdir;
+ snprintf (dir_template, sizeof dir_template, "%s/libguestfsXXXXXX", tmpdir);
+
/* Configured? */
if (!g->cmdline) {
- error (g, "you must call guestfs_add_drive before guestfs_launch");
+ error (g, _("you must call guestfs_add_drive before guestfs_launch"));
return -1;
}
if (g->state != CONFIG) {
- error (g, "qemu has already been launched");
+ error (g, _("qemu has already been launched"));
return -1;
}
- /* Search g->path for the kernel and initrd. */
+ /* Make the temporary directory. */
+ if (!g->tmpdir) {
+ g->tmpdir = safe_strdup (g, dir_template);
+ if (mkdtemp (g->tmpdir) == NULL) {
+ perrorf (g, _("%s: cannot create temporary directory"), dir_template);
+ goto cleanup0;
+ }
+ }
+
+ /* First search g->path for the supermin appliance, and try to
+ * synthesize a kernel and initrd from that. If it fails, we
+ * try the path search again looking for a backup ordinary
+ * appliance.
+ */
pelem = path = safe_strdup (g, g->path);
do {
pend = strchrnul (pelem, ':');
*pend = '\0';
len = pend - pelem;
- /* Empty element or "." means cwd. */
+ /* Empty element of "." means cwd. */
if (len == 0 || (len == 1 && *pelem == '.')) {
if (g->verbose)
- fprintf (stderr,
- "looking for kernel and initrd in current directory\n");
- if (access (kernel_name, F_OK) == 0 && access (initrd_name, F_OK) == 0) {
- kernel = safe_strdup (g, kernel_name);
- initrd = safe_strdup (g, initrd_name);
- break;
+ fprintf (stderr,
+ "looking for supermin appliance in current directory\n");
+ if (dir_contains_files (".",
+ supermin_name, supermin_hostfiles_name,
+ "kmod.whitelist", NULL)) {
+ if (build_supermin_appliance (g, ".", &kernel, &initrd) == -1)
+ return -1;
+ break;
}
}
- /* Look at <path>/kernel etc. */
+ /* Look at <path>/supermin* etc. */
else {
- kernel = safe_malloc (g, len + strlen (kernel_name) + 2);
- initrd = safe_malloc (g, len + strlen (initrd_name) + 2);
- sprintf (kernel, "%s/%s", pelem, kernel_name);
- sprintf (initrd, "%s/%s", pelem, initrd_name);
-
if (g->verbose)
- fprintf (stderr, "looking for %s and %s\n", kernel, initrd);
-
- if (access (kernel, F_OK) == 0 && access (initrd, F_OK) == 0)
- break;
- free (kernel);
- free (initrd);
- kernel = initrd = NULL;
+ fprintf (stderr, "looking for supermin appliance in %s\n", pelem);
+
+ if (dir_contains_files (pelem,
+ supermin_name, supermin_hostfiles_name,
+ "kmod.whitelist", NULL)) {
+ if (build_supermin_appliance (g, pelem, &kernel, &initrd) == -1)
+ return -1;
+ break;
+ }
}
pelem = pend + 1;
free (path);
if (kernel == NULL || initrd == NULL) {
- error (g, "cannot find %s or %s on LIBGUESTFS_PATH (current path = %s)",
- kernel_name, initrd_name, g->path);
+ /* Search g->path for the kernel and initrd. */
+ pelem = path = safe_strdup (g, g->path);
+ do {
+ pend = strchrnul (pelem, ':');
+ pmore = *pend == ':';
+ *pend = '\0';
+ len = pend - pelem;
+
+ /* Empty element or "." means cwd. */
+ if (len == 0 || (len == 1 && *pelem == '.')) {
+ if (g->verbose)
+ fprintf (stderr,
+ "looking for appliance in current directory\n");
+ if (dir_contains_files (".", kernel_name, initrd_name, NULL)) {
+ kernel = safe_strdup (g, kernel_name);
+ initrd = safe_strdup (g, initrd_name);
+ break;
+ }
+ }
+ /* Look at <path>/kernel etc. */
+ else {
+ if (g->verbose)
+ fprintf (stderr, "looking for appliance in %s\n", pelem);
+
+ if (dir_contains_files (pelem, kernel_name, initrd_name, NULL)) {
+ kernel = safe_malloc (g, len + strlen (kernel_name) + 2);
+ initrd = safe_malloc (g, len + strlen (initrd_name) + 2);
+ sprintf (kernel, "%s/%s", pelem, kernel_name);
+ sprintf (initrd, "%s/%s", pelem, initrd_name);
+ break;
+ }
+ }
+
+ pelem = pend + 1;
+ } while (pmore);
+
+ free (path);
+ }
+
+ if (kernel == NULL || initrd == NULL) {
+ error (g, _("cannot find %s or %s on LIBGUESTFS_PATH (current path = %s)"),
+ kernel_name, initrd_name, g->path);
goto cleanup0;
}
- /* Make the temporary directory containing the socket. */
- if (!g->tmpdir) {
- g->tmpdir = safe_strdup (g, dir_template);
- if (mkdtemp (g->tmpdir) == NULL) {
- perrorf (g, "%s: cannot create temporary directory", dir_template);
+ /* Get qemu help text and version. */
+ if (test_qemu (g) == -1)
+ goto cleanup0;
+
+ /* Choose which vmchannel implementation to use. */
+ if (qemu_supports (g, "-net user")) {
+ /* The "null vmchannel" implementation. Requires SLIRP (user mode
+ * networking in qemu) but no other vmchannel support. The daemon
+ * will connect back to a random port number on localhost.
+ */
+ struct sockaddr_in addr;
+ socklen_t addrlen = sizeof addr;
+
+ g->sock = socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);
+ if (g->sock == -1) {
+ perrorf (g, "socket");
+ goto cleanup0;
+ }
+ addr.sin_family = AF_INET;
+ addr.sin_port = htons (0);
+ addr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
+ if (bind (g->sock, (struct sockaddr *) &addr, addrlen) == -1) {
+ perrorf (g, "bind");
+ goto cleanup0;
+ }
+
+ if (listen (g->sock, 256) == -1) {
+ perrorf (g, "listen");
+ goto cleanup0;
+ }
+
+ if (getsockname (g->sock, (struct sockaddr *) &addr, &addrlen) == -1) {
+ perrorf (g, "getsockname");
+ goto cleanup0;
+ }
+
+ if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
goto cleanup0;
}
- }
- snprintf (unixsock, sizeof unixsock, "%s/sock", g->tmpdir);
- unlink (unixsock);
+ null_vmchannel_sock = ntohs (addr.sin_port);
+ if (g->verbose)
+ fprintf (stderr, "null_vmchannel_sock = %d\n", null_vmchannel_sock);
+ } else {
+ /* Using some vmchannel impl. We need to create a local Unix
+ * domain socket for qemu to use.
+ */
+ snprintf (unixsock, sizeof unixsock, "%s/sock", g->tmpdir);
+ unlink (unixsock);
+ null_vmchannel_sock = 0;
+ }
if (pipe (wfd) == -1 || pipe (rfd) == -1) {
perrorf (g, "pipe");
}
if (r == 0) { /* Child (qemu). */
- char vmchannel[256];
- char append[256];
+ char buf[256];
+ const char *vmchannel = NULL;
/* 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;
-
- /* Construct the -net channel parameter for qemu. */
- snprintf (vmchannel, sizeof vmchannel,
- "channel,%d:unix:%s,server,nowait",
- VMCHANNEL_PORT, unixsock);
-
- /* Linux kernel command line. */
- snprintf (append, sizeof append,
- "console=ttyS0 guestfs=%s:%d", VMCHANNEL_ADDR, VMCHANNEL_PORT);
+ g->cmdline[0] = g->qemu;
+ snprintf (buf, sizeof buf, "%d", g->memsize);
add_cmdline (g, "-m");
- add_cmdline (g, "384"); /* XXX Choose best size. */
- add_cmdline (g, "-no-kqemu"); /* Avoids a warning. */
- 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, buf);
+
+ add_cmdline (g, "-no-reboot"); /* Force exit instead of reboot on panic */
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, "%s", QEMU);
- for (i = 0; g->cmdline[i]; ++i)
- fprintf (stderr, " %s", g->cmdline[i]);
- fprintf (stderr, "\n");
- }
+ /* These options recommended by KVM developers to improve reliability. */
+ if (qemu_supports (g, "-no-hpet"))
+ add_cmdline (g, "-no-hpet");
- /* Set up stdin, stdout. */
- close (0);
- close (1);
- close (wfd[1]);
- close (rfd[0]);
- dup (wfd[0]);
- dup (rfd[1]);
- close (wfd[0]);
- close (rfd[1]);
+ if (qemu_supports (g, "-rtc-td-hack"))
+ add_cmdline (g, "-rtc-td-hack");
-#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).
+ /* If qemu has SLIRP (user mode network) enabled then we can get
+ * away with "no vmchannel", where we just connect back to a random
+ * host port.
*/
- setpgid (0, 0);
-#endif
+ if (null_vmchannel_sock) {
+ add_cmdline (g, "-net");
+ add_cmdline (g, "user,vlan=0,net=10.0.2.0/8");
- execv (QEMU, g->cmdline); /* Run qemu. */
- perror (QEMU);
- _exit (1);
- }
+ snprintf (buf, sizeof buf,
+ "guestfs_vmchannel=tcp:10.0.2.2:%d ", null_vmchannel_sock);
+ vmchannel = strdup (buf);
+ }
- /* Parent (library). */
- g->pid = r;
+ /* New-style -net user,guestfwd=... syntax for guestfwd. See:
+ *
+ * http://git.savannah.gnu.org/cgit/qemu.git/commit/?id=c92ef6a22d3c71538fcc48fb61ad353f7ba03b62
+ *
+ * The original suggested format doesn't work, see:
+ *
+ * http://lists.gnu.org/archive/html/qemu-devel/2009-07/msg01654.html
+ *
+ * However Gerd Hoffman privately suggested to me using -chardev
+ * instead, which does work.
+ */
+ else if (qemu_supports (g, "-chardev") && qemu_supports (g, "guestfwd")) {
+ snprintf (buf, sizeof buf,
+ "socket,id=guestfsvmc,path=%s,server,nowait", unixsock);
+
+ add_cmdline (g, "-chardev");
+ add_cmdline (g, buf);
+
+ snprintf (buf, sizeof buf,
+ "user,vlan=0,net=10.0.2.0/8,"
+ "guestfwd=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT
+ "-chardev:guestfsvmc");
+
+ add_cmdline (g, "-net");
+ add_cmdline (g, buf);
+
+ vmchannel = "guestfs_vmchannel=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT " ";
+ }
+
+ /* Not guestfwd. HOPEFULLY this qemu uses the older -net channel
+ * syntax, or if not then we'll get a quick failure.
+ */
+ else {
+ snprintf (buf, sizeof buf,
+ "channel," GUESTFWD_PORT ":unix:%s,server,nowait", unixsock);
+
+ add_cmdline (g, "-net");
+ add_cmdline (g, buf);
+ add_cmdline (g, "-net");
+ add_cmdline (g, "user,vlan=0,net=10.0.2.0/8");
+
+ vmchannel = "guestfs_vmchannel=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT " ";
+ }
+ add_cmdline (g, "-net");
+ add_cmdline (g, "nic,model=" NET_IF ",vlan=0");
+
+#define LINUX_CMDLINE \
+ "panic=1 " /* force kernel to panic if daemon exits */ \
+ "console=ttyS0 " /* serial console */ \
+ "udevtimeout=300 " /* good for very slow systems (RHBZ#480319) */ \
+ "noapic " /* workaround for RHBZ#502058 - ok if not SMP */ \
+ "acpi=off " /* we don't need ACPI, turn it off */ \
+ "cgroup_disable=memory " /* saves us about 5 MB of RAM */
+
+ /* Linux kernel command line. */
+ snprintf (buf, sizeof buf,
+ LINUX_CMDLINE
+ "%s" /* (selinux) */
+ "%s" /* (vmchannel) */
+ "%s" /* (verbose) */
+ "%s", /* (append) */
+ g->selinux ? "selinux=1 enforcing=0 " : "selinux=0 ",
+ vmchannel ? vmchannel : "",
+ g->verbose ? "guestfs_verbose=1 " : "",
+ g->append ? g->append : "");
+
+ 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, buf);
+
+ /* Finish off the command line. */
+ incr_cmdline_size (g);
+ g->cmdline[g->cmdline_size-1] = NULL;
+
+ if (g->verbose)
+ print_cmdline (g);
+
+ /* Set up stdin, stdout. */
+ close (0);
+ close (1);
+ close (wfd[1]);
+ close (rfd[0]);
+
+ if (dup (wfd[0]) == -1) {
+ dup_failed:
+ perror ("dup failed");
+ _exit (1);
+ }
+ if (dup (rfd[1]) == -1)
+ goto dup_failed;
+
+ close (wfd[0]);
+ close (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 (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);
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 (null_vmchannel_sock) {
+ int sock = -1;
+ uid_t uid;
- if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
- perrorf (g, "fcntl");
- goto cleanup2;
- }
+ /* Null vmchannel implementation: We listen on g->sock for a
+ * connection. The connection could come from any local process
+ * so we must check it comes from the appliance (or at least
+ * from our UID) for security reasons.
+ */
+ while (sock == -1) {
+ sock = accept_from_daemon (g);
+ if (sock == -1)
+ goto cleanup1;
+
+ if (check_peer_euid (g, sock, &uid) == -1)
+ goto cleanup1;
+ if (uid != geteuid ()) {
+ fprintf (stderr,
+ "libguestfs: warning: unexpected connection from UID %d to port %d\n",
+ uid, null_vmchannel_sock);
+ close (sock);
+ continue;
+ }
+ }
+
+ if (fcntl (sock, F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
+ goto cleanup1;
+ }
+
+ close (g->sock);
+ g->sock = sock;
+ } else {
+ /* Other vmchannel. 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;
+ }
- addr.sun_family = AF_UNIX;
- strncpy (addr.sun_path, unixsock, UNIX_PATH_MAX);
- addr.sun_path[UNIX_PATH_MAX-1] = '\0';
+ if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
+ goto cleanup1;
+ }
+
+ 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) {
+ tries = 100;
/* Always sleep at least once to give qemu a small chance to start up. */
usleep (10000);
+ while (tries > 0) {
+ r = connect (g->sock, (struct sockaddr *) &addr, sizeof addr);
+ if ((r == -1 && errno == EINPROGRESS) || r == 0)
+ goto connected;
+
+ if (errno != ENOENT)
+ perrorf (g, "connect");
+ tries--;
+ usleep (100000);
+ }
- r = connect (g->sock, (struct sockaddr *) &addr, sizeof addr);
- if ((r == -1 && errno == EINPROGRESS) || r == 0)
- goto connected;
+ error (g, _("failed to connect to vmchannel socket"));
+ goto cleanup1;
- if (errno != ENOENT)
- perrorf (g, "connect");
- tries--;
+ connected: ;
}
- error (g, "failed to connect to vmchannel socket");
- goto cleanup2;
+ g->state = LAUNCHING;
- connected:
- /* Watch the file descriptors. */
- free (g->msg_in);
- g->msg_in = NULL;
- g->msg_in_size = g->msg_in_allocated = 0;
+ /* Wait for qemu to start and to connect back to us via vmchannel and
+ * send the GUESTFS_LAUNCH_FLAG message.
+ */
+ uint32_t size;
+ void *buf = NULL;
+ r = recv_from_daemon (g, &size, &buf);
+ free (buf);
- free (g->msg_out);
- g->msg_out = NULL;
- g->msg_out_size = 0;
- g->msg_out_pos = 0;
+ if (r == -1) return -1;
- 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;
+ if (size != GUESTFS_LAUNCH_FLAG) {
+ error (g, _("guestfs_launch failed, see earlier error messages"));
+ goto cleanup1;
}
- g->sock_watch =
- main_loop.add_handle (g, g->sock,
- GUESTFS_HANDLE_READABLE,
- sock_read_event, g);
- if (g->sock_watch == -1) {
- error (g, "could not watch daemon communications socket");
- goto cleanup3;
+ /* 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"));
+ goto cleanup1;
}
- 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);
+ 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;
cleanup0:
+ if (g->sock >= 0) {
+ close (g->sock);
+ g->sock = -1;
+ }
+ g->state = CONFIG;
free (kernel);
free (initrd);
return -1;
}
+/* This function is used to print the qemu command line before it gets
+ * executed, when in verbose mode.
+ */
static void
-finish_wait_ready (guestfs_h *g, void *vp)
+print_cmdline (guestfs_h *g)
{
- *((int *)vp) = 1;
- main_loop.main_loop_quit (g);
+ int i = 0;
+ int needs_quote;
+
+ while (g->cmdline[i]) {
+ if (g->cmdline[i][0] == '-') /* -option starts a new line */
+ fprintf (stderr, " \\\n ");
+
+ if (i > 0) fputc (' ', stderr);
+
+ /* Does it need shell quoting? This only deals with simple cases. */
+ needs_quote = strcspn (g->cmdline[i], " ") != strlen (g->cmdline[i]);
+
+ if (needs_quote) fputc ('\'', stderr);
+ fprintf (stderr, "%s", g->cmdline[i]);
+ if (needs_quote) fputc ('\'', stderr);
+ i++;
+ }
+
+ fputc ('\n', stderr);
}
-int
-guestfs_wait_ready (guestfs_h *g)
+/* This function does the hard work of building the supermin appliance
+ * on the fly. 'path' is the directory containing the control files.
+ * 'kernel' and 'initrd' are where we will return the names of the
+ * kernel and initrd (only initrd is built). The work is done by
+ * an external script. We just tell it where to put the result.
+ */
+static int
+build_supermin_appliance (guestfs_h *g, const char *path,
+ char **kernel, char **initrd)
+{
+ char cmd[4096];
+ int r, len;
+
+ len = strlen (g->tmpdir);
+ *kernel = safe_malloc (g, len + 8);
+ snprintf (*kernel, len+8, "%s/kernel", g->tmpdir);
+ *initrd = safe_malloc (g, len + 8);
+ snprintf (*initrd, len+8, "%s/initrd", g->tmpdir);
+
+ snprintf (cmd, sizeof cmd,
+ "PATH='%s':$PATH "
+ "libguestfs-supermin-helper '%s' %s %s",
+ path,
+ path, *kernel, *initrd);
+
+ r = system (cmd);
+ if (r == -1 || WEXITSTATUS(r) != 0) {
+ error (g, _("external command failed: %s"), cmd);
+ free (*kernel);
+ free (*initrd);
+ *kernel = *initrd = NULL;
+ return -1;
+ }
+
+ return 0;
+}
+
+static int read_all (guestfs_h *g, FILE *fp, char **ret);
+
+/* Test qemu binary (or wrapper) runs, and do 'qemu -help' and
+ * 'qemu -version' so we know what options this qemu supports and
+ * the version.
+ */
+static int
+test_qemu (guestfs_h *g)
+{
+ char cmd[1024];
+ FILE *fp;
+
+ free (g->qemu_help);
+ free (g->qemu_version);
+ g->qemu_help = NULL;
+ g->qemu_version = NULL;
+
+ snprintf (cmd, sizeof cmd, "'%s' -help", g->qemu);
+
+ fp = popen (cmd, "r");
+ /* qemu -help should always work (qemu -version OTOH wasn't
+ * supported by qemu 0.9). If this command doesn't work then it
+ * probably indicates that the qemu binary is missing.
+ */
+ if (!fp) {
+ /* XXX This error is never printed, even if the qemu binary
+ * doesn't exist. Why?
+ */
+ error:
+ perrorf (g, _("%s: command failed: If qemu is located on a non-standard path, try setting the LIBGUESTFS_QEMU environment variable."), cmd);
+ return -1;
+ }
+
+ if (read_all (g, fp, &g->qemu_help) == -1)
+ goto error;
+
+ if (pclose (fp) == -1)
+ goto error;
+
+ snprintf (cmd, sizeof cmd, "'%s' -version 2>/dev/null", g->qemu);
+
+ fp = popen (cmd, "r");
+ if (fp) {
+ /* Intentionally ignore errors. */
+ read_all (g, fp, &g->qemu_version);
+ pclose (fp);
+ }
+
+ return 0;
+}
+
+static int
+read_all (guestfs_h *g, FILE *fp, char **ret)
{
- int r = 0;
+ int r, n = 0;
+ char *p;
- if (g->state == READY) return 0;
+ again:
+ if (feof (fp)) {
+ *ret = safe_realloc (g, *ret, n + 1);
+ (*ret)[n] = '\0';
+ return n;
+ }
- if (g->state == BUSY) {
- error (g, "qemu has finished launching already");
+ *ret = safe_realloc (g, *ret, n + BUFSIZ);
+ p = &(*ret)[n];
+ r = fread (p, 1, BUFSIZ, fp);
+ if (ferror (fp)) {
+ perrorf (g, "read");
return -1;
}
+ n += r;
+ goto again;
+}
+
+/* Test if option is supported by qemu command line (just by grepping
+ * the help text).
+ */
+static int
+qemu_supports (guestfs_h *g, const char *option)
+{
+ return g->qemu_help && strstr (g->qemu_help, option) != NULL;
+}
+
+/* Check the peer effective UID for a TCP socket. Ideally we'd like
+ * SO_PEERCRED for a loopback TCP socket. This isn't possible on
+ * Linux (but it is on Solaris!) so we read /proc/net/tcp instead.
+ */
+static int
+check_peer_euid (guestfs_h *g, int sock, uid_t *rtn)
+{
+ struct sockaddr_in peer;
+ socklen_t addrlen = sizeof peer;
- if (g->state != LAUNCHING) {
- error (g, "qemu has not been launched yet");
+ if (getpeername (sock, (struct sockaddr *) &peer, &addrlen) == -1) {
+ perrorf (g, "getpeername");
return -1;
}
- 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 (peer.sin_family != AF_INET ||
+ ntohl (peer.sin_addr.s_addr) != INADDR_LOOPBACK) {
+ error (g, "check_peer_euid: unexpected connection from non-IPv4, non-loopback peer (family = %d, addr = %s)",
+ peer.sin_family, inet_ntoa (peer.sin_addr));
+ return -1;
+ }
- if (r != 1) {
- error (g, "guestfs_wait_ready failed, see earlier error messages");
+ struct sockaddr_in our;
+ addrlen = sizeof our;
+ if (getsockname (sock, (struct sockaddr *) &our, &addrlen) == -1) {
+ perrorf (g, "getsockname");
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");
+ FILE *fp = fopen ("/proc/net/tcp", "r");
+ if (fp == NULL) {
+ perrorf (g, "/proc/net/tcp");
+ return -1;
+ }
+
+ char line[256];
+ if (fgets (line, sizeof line, fp) == NULL) { /* Drop first line. */
+ error (g, "unexpected end of file in /proc/net/tcp");
+ fclose (fp);
+ return -1;
+ }
+
+ while (fgets (line, sizeof line, fp) != NULL) {
+ unsigned line_our_addr, line_our_port, line_peer_addr, line_peer_port;
+ int dummy0, dummy1, dummy2, dummy3, dummy4, dummy5, dummy6;
+ int line_uid;
+
+ if (sscanf (line, "%d:%08X:%04X %08X:%04X %02X %08X:%08X %02X:%08X %08X %d",
+ &dummy0,
+ &line_our_addr, &line_our_port,
+ &line_peer_addr, &line_peer_port,
+ &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, &dummy6,
+ &line_uid) == 12) {
+ /* Note about /proc/net/tcp: local_address and rem_address are
+ * always in network byte order. However the port part is
+ * always in host byte order.
+ *
+ * The sockname and peername that we got above are in network
+ * byte order. So we have to byte swap the port but not the
+ * address part.
+ */
+ if (line_our_addr == our.sin_addr.s_addr &&
+ line_our_port == ntohs (our.sin_port) &&
+ line_peer_addr == peer.sin_addr.s_addr &&
+ line_peer_port == ntohs (peer.sin_port)) {
+ *rtn = line_uid;
+ fclose (fp);
+ return 0;
+ }
+ }
+ }
+
+ error (g, "check_peer_euid: no matching TCP connection found in /proc/net/tcp");
+ fclose (fp);
+ return -1;
+}
+
+/* You had to call this function after launch in versions <= 1.0.70,
+ * but it is now a no-op.
+ */
+int
+guestfs__wait_ready (guestfs_h *g)
+{
+ if (g->state != READY) {
+ error (g, _("qemu has not been launched yet"));
return -1;
}
}
int
-guestfs_kill_subprocess (guestfs_h *g)
+guestfs__kill_subprocess (guestfs_h *g)
{
if (g->state == CONFIG) {
- error (g, "no subprocess to kill");
+ error (g, _("no subprocess to kill"));
return -1;
}
fprintf (stderr, "sending SIGTERM to process %d\n", g->pid);
kill (g->pid, SIGTERM);
+ if (g->recoverypid > 0) kill (g->recoverypid, 9);
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.
+/* Access current state. */
+int
+guestfs__is_config (guestfs_h *g)
+{
+ return g->state == CONFIG;
+}
+
+int
+guestfs__is_launching (guestfs_h *g)
+{
+ return g->state == LAUNCHING;
+}
+
+int
+guestfs__is_ready (guestfs_h *g)
+{
+ return g->state == READY;
+}
+
+int
+guestfs__is_busy (guestfs_h *g)
+{
+ return g->state == BUSY;
+}
+
+int
+guestfs__get_state (guestfs_h *g)
+{
+ return g->state;
+}
+
+void
+guestfs_set_log_message_callback (guestfs_h *g,
+ guestfs_log_message_cb cb, void *opaque)
+{
+ g->log_message_cb = cb;
+ g->log_message_cb_data = opaque;
+}
+
+void
+guestfs_set_subprocess_quit_callback (guestfs_h *g,
+ guestfs_subprocess_quit_cb cb, void *opaque)
+{
+ g->subprocess_quit_cb = cb;
+ g->subprocess_quit_cb_data = opaque;
+}
+
+void
+guestfs_set_launch_done_callback (guestfs_h *g,
+ guestfs_launch_done_cb cb, void *opaque)
+{
+ g->launch_done_cb = cb;
+ g->launch_done_cb_data = opaque;
+}
+
+/*----------------------------------------------------------------------*/
+
+/* This is the code used to send and receive RPC messages and (for
+ * certain types of message) to perform file transfers. This code is
+ * driven from the generated actions (src/guestfs-actions.c). There
+ * are five different cases to consider:
+ *
+ * (1) A non-daemon function. There is no RPC involved at all, it's
+ * all handled inside the library.
+ *
+ * (2) A simple RPC (eg. "mount"). We write the request, then read
+ * the reply. The sequence of calls is:
+ *
+ * guestfs___set_busy
+ * guestfs___send
+ * guestfs___recv
+ * guestfs___end_busy
+ *
+ * (3) An RPC with FileOut parameters (eg. "upload"). We write the
+ * request, then write the file(s), then read the reply. The sequence
+ * of calls is:
+ *
+ * guestfs___set_busy
+ * guestfs___send
+ * guestfs___send_file (possibly multiple times)
+ * guestfs___recv
+ * guestfs___end_busy
+ *
+ * (4) An RPC with FileIn parameters (eg. "download"). We write the
+ * request, then read the reply, then read the file(s). The sequence
+ * of calls is:
+ *
+ * guestfs___set_busy
+ * guestfs___send
+ * guestfs___recv
+ * guestfs___recv_file (possibly multiple times)
+ * guestfs___end_busy
+ *
+ * (5) Both FileOut and FileIn parameters. There are no calls like
+ * this in the current API, but they would be implemented as a
+ * combination of cases (3) and (4).
+ *
+ * During all writes and reads, we also select(2) on qemu stdout
+ * looking for messages (guestfsd stderr and guest kernel dmesg), and
+ * anything received is passed up through the log_message_cb. This is
+ * also the reason why all the sockets are non-blocking. We also have
+ * to check for EOF (qemu died). All of this is handled by the
+ * functions send_to_daemon and recv_from_daemon.
*/
+
+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:
+ default:
+ error (g, _("guestfs_end_busy: called when in state %d"), g->state);
+ return -1;
+ }
+ return 0;
+}
+
+/* This is called if we detect EOF, ie. qemu died. */
static void
-stdout_event (void *data, int watch, int fd, int events)
+child_cleanup (guestfs_h *g)
+{
+ if (g->verbose)
+ fprintf (stderr, "child_cleanup: %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);
+ 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->state = CONFIG;
+ if (g->subprocess_quit_cb)
+ g->subprocess_quit_cb (g, g->subprocess_quit_cb_data);
+}
+
+static int
+read_log_message_or_eof (guestfs_h *g, int fd)
{
- guestfs_h *g = (guestfs_h *) data;
- char buf[4096];
+ char buf[BUFSIZ];
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);
+ "read_log_message_or_eof: %p g->state = %d, fd = %d\n",
+ g, g->state, fd);
#endif
- if (g->fd[1] != fd) {
- error (g, "stdout_event: internal error: %d != %d", g->fd[1], fd);
- return;
- }
-
+ /* QEMU's console emulates a 16550A serial port. The real 16550A
+ * device has a small FIFO buffer (16 bytes) which means here we see
+ * lots of small reads of 1-16 bytes in length, usually single
+ * bytes.
+ */
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;
+ child_cleanup (g);
+ return -1;
}
if (n == -1) {
- if (errno != EAGAIN)
- perrorf (g, "read");
- return;
+ if (errno == EINTR || errno == EAGAIN)
+ return 0;
+
+ perrorf (g, "read");
+ return -1;
}
/* In verbose mode, copy all log messages to stderr. */
if (g->verbose)
- write (2, buf, n);
+ ignore_value (write (STDERR_FILENO, 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);
+
+ return 0;
}
-/* 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)
+static int
+check_for_daemon_cancellation_or_eof (guestfs_h *g, int fd)
{
- guestfs_h *g = (guestfs_h *) data;
- XDR xdr;
- unsigned len;
+ char buf[4];
int n;
+ uint32_t flag;
+ XDR xdr;
if (g->verbose)
fprintf (stderr,
- "sock_read_event: %p g->state = %d, fd = %d, events = 0x%x\n",
- g, g->state, fd, events);
-
- if (g->sock != fd) {
- error (g, "sock_read_event: internal error: %d != %d", g->sock, fd);
- return;
- }
+ "check_for_daemon_cancellation_or_eof: %p g->state = %d, fd = %d\n",
+ g, g->state, fd);
- if (g->msg_in_size <= g->msg_in_allocated) {
- g->msg_in_allocated += 4096;
- g->msg_in = safe_realloc (g, g->msg_in, g->msg_in_allocated);
+ n = read (fd, buf, 4);
+ if (n == 0) {
+ /* Hopefully this indicates the qemu child process has died. */
+ child_cleanup (g);
+ return -1;
}
- 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.
- */
- return;
if (n == -1) {
- if (errno != EAGAIN)
- perrorf (g, "read");
- return;
- }
+ if (errno == EINTR || errno == EAGAIN)
+ return 0;
- g->msg_in_size += n;
+ perrorf (g, "read");
+ return -1;
+ }
- /* Have we got enough of a message to be able to process it yet? */
- if (g->msg_in_size < 4) return;
+ xdrmem_create (&xdr, buf, 4, XDR_DECODE);
+ xdr_uint32_t (&xdr, &flag);
+ xdr_destroy (&xdr);
- xdrmem_create (&xdr, g->msg_in, g->msg_in_size, XDR_DECODE);
- if (!xdr_uint32_t (&xdr, &len)) {
- error (g, "can't decode length word");
- goto cleanup;
+ if (flag != GUESTFS_CANCEL_FLAG) {
+ error (g, _("check_for_daemon_cancellation_or_eof: read 0x%x from daemon, expected 0x%x\n"),
+ flag, GUESTFS_CANCEL_FLAG);
+ return -1;
}
- /* Length is normally the length of the message, but when guestfsd
- * starts up it sends a "magic" value (longer than any possible
- * message). Check for this.
- */
- if (len == 0xf5f55ff5) {
- if (g->state != LAUNCHING)
- error (g, "received magic signature from guestfsd, but in state %d",
- g->state);
- else if (g->msg_in_size != 4)
- error (g, "received magic signature from guestfsd, but msg size is %d",
- g->msg_in_size);
- else {
- g->state = READY;
- if (g->launch_done_cb_internal)
- g->launch_done_cb_internal (g, g->launch_done_cb_internal_data);
- if (g->launch_done_cb)
- g->launch_done_cb (g, g->launch_done_cb_data);
- }
+ return -2;
+}
- goto cleanup;
- }
+/* This writes the whole N bytes of BUF to the daemon socket.
+ *
+ * If the whole write is successful, it returns 0.
+ * If there was an error, it returns -1.
+ * If the daemon sent a cancellation message, it returns -2.
+ *
+ * It also checks qemu stdout for log messages and passes those up
+ * through log_message_cb.
+ *
+ * It also checks for EOF (qemu died) and passes that up through the
+ * child_cleanup function above.
+ */
+static int
+send_to_daemon (guestfs_h *g, const void *v_buf, size_t n)
+{
+ const char *buf = v_buf;
+ fd_set rset, rset2;
+ fd_set wset, wset2;
- /* 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);
- goto cleanup;
- }
+ if (g->verbose)
+ fprintf (stderr,
+ "send_to_daemon: %p g->state = %d, n = %zu\n", g, g->state, n);
- if (g->msg_in_size-4 < len) return; /* Need more of this message. */
+ FD_ZERO (&rset);
+ FD_ZERO (&wset);
- /* 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;
- }
+ FD_SET (g->fd[1], &rset); /* Read qemu stdout for log messages & EOF. */
+ FD_SET (g->sock, &rset); /* Read socket for cancellation & EOF. */
+ FD_SET (g->sock, &wset); /* Write to socket to send the data. */
- /* Not in the expected state. */
- if (g->state != BUSY)
- error (g, "state %d != BUSY", g->state);
+ int max_fd = MAX (g->sock, g->fd[1]);
- /* Push the message up to the higher layer. Note that unlike
- * launch_done_cb / launch_done_cb_internal, we only call at
- * most one of the callback functions here.
- */
- g->state = READY;
- if (g->reply_cb_internal)
- g->reply_cb_internal (g, g->reply_cb_internal_data, &xdr);
- else if (g->reply_cb)
- g->reply_cb (g, g->reply_cb, &xdr);
-
- cleanup:
- /* Free the message buffer if it's grown excessively large. */
- if (g->msg_in_allocated > 65536) {
- free (g->msg_in);
- g->msg_in = NULL;
- g->msg_in_size = g->msg_in_allocated = 0;
- } else
- g->msg_in_size = 0;
+ while (n > 0) {
+ rset2 = rset;
+ wset2 = wset;
+ int r = select (max_fd+1, &rset2, &wset2, NULL, NULL);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "select");
+ return -1;
+ }
- xdr_destroy (&xdr);
+ if (FD_ISSET (g->fd[1], &rset2)) {
+ if (read_log_message_or_eof (g, g->fd[1]) == -1)
+ return -1;
+ }
+ if (FD_ISSET (g->sock, &rset2)) {
+ r = check_for_daemon_cancellation_or_eof (g, g->sock);
+ if (r < 0)
+ return r;
+ }
+ if (FD_ISSET (g->sock, &wset2)) {
+ r = write (g->sock, buf, n);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "write");
+ if (errno == EPIPE) /* Disconnected from guest (RHBZ#508713). */
+ child_cleanup (g);
+ return -1;
+ }
+ buf += r;
+ n -= r;
+ }
+ }
+
+ return 0;
}
-/* The function is called whenever we can write something on the
- * guestfsd (daemon inside the guest) communication socket.
+/* This reads a single message, file chunk, launch flag or
+ * cancellation flag from the daemon. If something was read, it
+ * returns 0, otherwise -1.
+ *
+ * Both size_rtn and buf_rtn must be passed by the caller as non-NULL.
+ *
+ * *size_rtn returns the size of the returned message or it may be
+ * GUESTFS_LAUNCH_FLAG or GUESTFS_CANCEL_FLAG.
+ *
+ * *buf_rtn is returned containing the message (if any) or will be set
+ * to NULL. *buf_rtn must be freed by the caller.
+ *
+ * It also checks qemu stdout for log messages and passes those up
+ * through log_message_cb.
+ *
+ * It also checks for EOF (qemu died) and passes that up through the
+ * child_cleanup function above.
*/
-static void
-sock_write_event (void *data, int watch, int fd, int events)
+static int
+recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn)
{
- guestfs_h *g = (guestfs_h *) data;
- int n;
+ fd_set rset, rset2;
if (g->verbose)
fprintf (stderr,
- "sock_write_event: %p g->state = %d, fd = %d, events = 0x%x\n",
- g, g->state, fd, events);
+ "recv_from_daemon: %p g->state = %d, size_rtn = %p, buf_rtn = %p\n",
+ g, g->state, size_rtn, buf_rtn);
- if (g->sock != fd) {
- error (g, "sock_write_event: internal error: %d != %d", g->sock, fd);
- return;
+ FD_ZERO (&rset);
+
+ FD_SET (g->fd[1], &rset); /* Read qemu stdout for log messages & EOF. */
+ FD_SET (g->sock, &rset); /* Read socket for data & EOF. */
+
+ int max_fd = MAX (g->sock, g->fd[1]);
+
+ *size_rtn = 0;
+ *buf_rtn = NULL;
+
+ char lenbuf[4];
+ /* nr is the size of the message, but we prime it as -4 because we
+ * have to read the message length word first.
+ */
+ ssize_t nr = -4;
+
+ while (nr < (ssize_t) *size_rtn) {
+ rset2 = rset;
+ int r = select (max_fd+1, &rset2, NULL, NULL, NULL);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "select");
+ free (*buf_rtn);
+ *buf_rtn = NULL;
+ return -1;
+ }
+
+ if (FD_ISSET (g->fd[1], &rset2)) {
+ if (read_log_message_or_eof (g, g->fd[1]) == -1) {
+ free (*buf_rtn);
+ *buf_rtn = NULL;
+ return -1;
+ }
+ }
+ if (FD_ISSET (g->sock, &rset2)) {
+ if (nr < 0) { /* Have we read the message length word yet? */
+ r = read (g->sock, lenbuf+nr+4, -nr);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ int err = errno;
+ perrorf (g, "read");
+ /* Under some circumstances we see "Connection reset by peer"
+ * here when the child dies suddenly. Catch this and call
+ * the cleanup function, same as for EOF.
+ */
+ if (err == ECONNRESET)
+ child_cleanup (g);
+ return -1;
+ }
+ if (r == 0) {
+ error (g, _("unexpected end of file when reading from daemon"));
+ child_cleanup (g);
+ return -1;
+ }
+ nr += r;
+
+ if (nr < 0) /* Still not got the whole length word. */
+ continue;
+
+ XDR xdr;
+ xdrmem_create (&xdr, lenbuf, 4, XDR_DECODE);
+ xdr_uint32_t (&xdr, size_rtn);
+ xdr_destroy (&xdr);
+
+ if (*size_rtn == GUESTFS_LAUNCH_FLAG) {
+ if (g->state != LAUNCHING)
+ error (g, _("received magic signature from guestfsd, but in state %d"),
+ g->state);
+ else {
+ g->state = READY;
+ if (g->launch_done_cb)
+ g->launch_done_cb (g, g->launch_done_cb_data);
+ }
+ return 0;
+ }
+ else if (*size_rtn == GUESTFS_CANCEL_FLAG)
+ return 0;
+ /* If this happens, it's pretty bad and we've probably lost
+ * synchronization.
+ */
+ else if (*size_rtn > GUESTFS_MESSAGE_MAX) {
+ error (g, _("message length (%u) > maximum possible size (%d)"),
+ (unsigned) *size_rtn, GUESTFS_MESSAGE_MAX);
+ return -1;
+ }
+
+ /* Allocate the complete buffer, size now known. */
+ *buf_rtn = safe_malloc (g, *size_rtn);
+ /*FALLTHROUGH*/
+ }
+
+ size_t sizetoread = *size_rtn - nr;
+ if (sizetoread > BUFSIZ) sizetoread = BUFSIZ;
+
+ r = read (g->sock, (char *) (*buf_rtn) + nr, sizetoread);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "read");
+ free (*buf_rtn);
+ *buf_rtn = NULL;
+ return -1;
+ }
+ if (r == 0) {
+ error (g, _("unexpected end of file when reading from daemon"));
+ child_cleanup (g);
+ free (*buf_rtn);
+ *buf_rtn = NULL;
+ return -1;
+ }
+ nr += r;
+ }
}
- if (g->state != BUSY) {
- error (g, "sock_write_event: state %d != BUSY", g->state);
- return;
+ /* Got the full message, caller can start processing it. */
+#ifdef ENABLE_PACKET_DUMP
+ if (g->verbose) {
+ ssize_t i, j;
+
+ for (i = 0; i < nr; i += 16) {
+ printf ("%04zx: ", i);
+ for (j = i; j < MIN (i+16, nr); ++j)
+ printf ("%02x ", (*(unsigned char **)buf_rtn)[j]);
+ for (; j < i+16; ++j)
+ printf (" ");
+ printf ("|");
+ for (j = i; j < MIN (i+16, nr); ++j)
+ if (isprint ((*(char **)buf_rtn)[j]))
+ printf ("%c", (*(char **)buf_rtn)[j]);
+ else
+ printf (".");
+ for (; j < i+16; ++j)
+ printf (" ");
+ printf ("|\n");
+ }
}
+#endif
- if (g->verbose)
- fprintf (stderr, "sock_write_event: writing %d bytes ...\n",
- g->msg_out_size - g->msg_out_pos);
+ return 0;
+}
- n = write (g->sock, g->msg_out + g->msg_out_pos,
- g->msg_out_size - g->msg_out_pos);
- if (n == -1) {
- if (errno != EAGAIN)
- perrorf (g, "write");
- return;
- }
+/* This is very much like recv_from_daemon above, but g->sock is
+ * a listening socket and we are accepting a new connection on
+ * that socket instead of reading anything. Returns the newly
+ * accepted socket.
+ */
+static int
+accept_from_daemon (guestfs_h *g)
+{
+ fd_set rset, rset2;
if (g->verbose)
- fprintf (stderr, "sock_write_event: wrote %d bytes\n", n);
+ fprintf (stderr,
+ "accept_from_daemon: %p g->state = %d\n", g, g->state);
- g->msg_out_pos += n;
+ FD_ZERO (&rset);
- /* More to write? */
- if (g->msg_out_pos < g->msg_out_size)
- return;
+ FD_SET (g->fd[1], &rset); /* Read qemu stdout for log messages & EOF. */
+ FD_SET (g->sock, &rset); /* Read socket for accept. */
- if (g->verbose)
- fprintf (stderr, "sock_write_event: done writing, switching back to reading events\n");
+ int max_fd = MAX (g->sock, g->fd[1]);
+ int sock = -1;
- free (g->msg_out);
- g->msg_out_pos = g->msg_out_size = 0;
+ while (sock == -1) {
+ rset2 = rset;
+ int r = select (max_fd+1, &rset2, NULL, NULL, NULL);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "select");
+ return -1;
+ }
- if (main_loop.remove_handle (g, g->sock_watch) == -1) {
- error (g, "remove_handle failed in sock_write_event");
- return;
- }
- g->sock_watch =
- main_loop.add_handle (g, g->sock,
- GUESTFS_HANDLE_READABLE,
- sock_read_event, g);
- if (g->sock_watch == -1) {
- error (g, "add_handle failed in sock_write_event");
- return;
+ if (FD_ISSET (g->fd[1], &rset2)) {
+ if (read_log_message_or_eof (g, g->fd[1]) == -1)
+ return -1;
+ }
+ if (FD_ISSET (g->sock, &rset2)) {
+ sock = accept (g->sock, NULL, NULL);
+ if (sock == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "accept");
+ return -1;
+ }
+ }
}
+
+ return sock;
}
-/* Dispatch a call 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.
- */
-static int
-dispatch (guestfs_h *g, int proc_nr, xdrproc_t xdrp, char *args)
+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;
+ u_int32_t len;
int serial = g->msg_next_serial++;
+ int r;
+ char *msg_out;
+ size_t msg_out_size;
- if (g->state != READY) {
- error (g, "dispatch: state %d != READY", g->state);
+ if (g->state != BUSY) {
+ error (g, _("guestfs___send: state %d != BUSY"), g->state);
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.
+ */
+ msg_out = safe_malloc (g, GUESTFS_MESSAGE_MAX + 4);
+ xdrmem_create (&xdr, msg_out + 4, GUESTFS_MESSAGE_MAX, XDR_ENCODE);
+
/* Serialize the header. */
hdr.prog = GUESTFS_PROGRAM;
hdr.vers = GUESTFS_PROTOCOL_VERSION;
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;
+ error (g, _("xdr_guestfs_message_header failed"));
+ goto cleanup1;
}
/* Serialize the args. If any, because some message types
*/
if (xdrp) {
if (!(*xdrp) (&xdr, args)) {
- error (g, "dispatch failed to marshal args");
- return -1;
+ 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);
- /* 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;
- }
+ msg_out = safe_realloc (g, msg_out, len + 4);
+ msg_out_size = len + 4;
- memcpy (g->msg_out + 4, buffer, len);
+ xdrmem_create (&xdr, msg_out, 4, XDR_ENCODE);
+ xdr_uint32_t (&xdr, &len);
- /* Change the handle to sock_write_event. */
- if (main_loop.remove_handle (g, g->sock_watch) == -1) {
- error (g, "remove_handle failed in dispatch");
- goto cleanup1;
- }
- g->sock_watch =
- main_loop.add_handle (g, g->sock,
- GUESTFS_HANDLE_WRITABLE,
- sock_write_event, g);
- if (g->sock_watch == -1) {
- error (g, "add_handle failed in dispatch");
+ again:
+ r = send_to_daemon (g, msg_out, msg_out_size);
+ if (r == -2) /* Ignore stray daemon cancellations. */
+ goto again;
+ if (r == -1)
goto cleanup1;
- }
+ free (msg_out);
return serial;
cleanup1:
- free (g->msg_out);
- g->msg_out = NULL;
- g->msg_out_size = 0;
- g->state = READY;
+ free (msg_out);
return -1;
}
-/* Check the return message from a call for validity. */
-static int
-check_reply_header (guestfs_h *g,
- const struct guestfs_message_header *hdr,
- int proc_nr, int serial)
+static int cancel = 0; /* XXX Implement file cancellation. */
+static int send_file_chunk (guestfs_h *g, int cancel, const char *buf, size_t len);
+static int send_file_data (guestfs_h *g, const char *buf, size_t len);
+static int send_file_cancellation (guestfs_h *g);
+static int send_file_complete (guestfs_h *g);
+
+/* 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)
{
- if (hdr->prog != GUESTFS_PROGRAM) {
- error (g, "wrong program (%d/%d)", hdr->prog, GUESTFS_PROGRAM);
+ char buf[GUESTFS_MAX_CHUNK_SIZE];
+ int fd, r, err;
+
+ fd = open (filename, O_RDONLY);
+ if (fd == -1) {
+ perrorf (g, "open: %s", filename);
+ send_file_cancellation (g);
+ /* Daemon sees cancellation and won't reply, so caller can
+ * just return here.
+ */
return -1;
}
- if (hdr->vers != GUESTFS_PROTOCOL_VERSION) {
- error (g, "wrong protocol version (%d/%d)",
- hdr->vers, GUESTFS_PROTOCOL_VERSION);
- return -1;
+
+ /* Send file in chunked encoding. */
+ while (!cancel) {
+ r = read (fd, buf, sizeof buf);
+ if (r == -1 && (errno == EINTR || errno == EAGAIN))
+ continue;
+ if (r <= 0) break;
+ err = send_file_data (g, buf, r);
+ if (err < 0) {
+ if (err == -2) /* daemon sent cancellation */
+ send_file_cancellation (g);
+ return err;
+ }
}
- if (hdr->direction != GUESTFS_DIRECTION_REPLY) {
- error (g, "unexpected message direction (%d/%d)",
- hdr->direction, GUESTFS_DIRECTION_REPLY);
+
+ if (cancel) { /* cancel from either end */
+ send_file_cancellation (g);
return -1;
}
- if (hdr->proc != proc_nr) {
- error (g, "unexpected procedure number (%d/%d)", hdr->proc, proc_nr);
+
+ if (r == -1) {
+ perrorf (g, "read: %s", filename);
+ send_file_cancellation (g);
return -1;
}
- if (hdr->serial != serial) {
- error (g, "unexpected serial (%d/%d)", hdr->serial, serial);
+
+ /* End of file, but before we send that, we need to close
+ * the file and check for errors.
+ */
+ if (close (fd) == -1) {
+ perrorf (g, "close: %s", filename);
+ send_file_cancellation (g);
return -1;
}
- return 0;
+ return send_file_complete (g);
}
-/* The high-level actions are autogenerated by generator.ml. Include
- * them here.
- */
-#include "guestfs-actions.c"
-
-/* This is the default main loop implementation, using select(2). */
-
-struct handle_cb_data {
- guestfs_handle_event_cb cb;
- void *data;
-};
-
-static fd_set rset;
-static fd_set wset;
-static fd_set xset;
-static int select_init_done = 0;
-static int max_fd = -1;
-static int nr_fds = 0;
-static struct handle_cb_data *handle_cb_data = NULL;
+/* Send a chunk of file data. */
+static int
+send_file_data (guestfs_h *g, const char *buf, size_t len)
+{
+ return send_file_chunk (g, 0, buf, len);
+}
-static void
-select_init (void)
+/* Send a cancellation message. */
+static int
+send_file_cancellation (guestfs_h *g)
{
- if (!select_init_done) {
- FD_ZERO (&rset);
- FD_ZERO (&wset);
- FD_ZERO (&xset);
+ return send_file_chunk (g, 1, NULL, 0);
+}
- select_init_done = 1;
- }
+/* Send a file complete chunk. */
+static int
+send_file_complete (guestfs_h *g)
+{
+ char buf[1];
+ return send_file_chunk (g, 0, buf, 0);
}
static int
-select_add_handle (guestfs_h *g, int fd, int events,
- guestfs_handle_event_cb cb, void *data)
+send_file_chunk (guestfs_h *g, int cancel, const char *buf, size_t buflen)
{
- select_init ();
+ u_int32_t len;
+ int r;
+ guestfs_chunk chunk;
+ XDR xdr;
+ char *msg_out;
+ size_t msg_out_size;
- if (fd < 0 || fd >= FD_SETSIZE) {
- error (g, "fd %d is out of range", fd);
+ if (g->state != BUSY) {
+ error (g, _("send_file_chunk: state %d != READY"), g->state);
return -1;
}
- 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;
+ /* Allocate the chunk buffer. Don't use the stack to avoid
+ * excessive stack usage and unnecessary copies.
+ */
+ msg_out = safe_malloc (g, GUESTFS_MAX_CHUNK_SIZE + 4 + 48);
+ xdrmem_create (&xdr, msg_out + 4, GUESTFS_MAX_CHUNK_SIZE + 48, XDR_ENCODE);
+
+ /* Serialize the chunk. */
+ chunk.cancel = cancel;
+ chunk.data.data_len = buflen;
+ chunk.data.data_val = (char *) buf;
+
+ if (!xdr_guestfs_chunk (&xdr, &chunk)) {
+ error (g, _("xdr_guestfs_chunk failed (buf = %p, buflen = %zu)"),
+ buf, buflen);
+ xdr_destroy (&xdr);
+ goto cleanup1;
}
- if (events == 0) {
- error (g, "set of events is empty");
- return -1;
- }
+ len = xdr_getpos (&xdr);
+ xdr_destroy (&xdr);
- if (FD_ISSET (fd, &rset) || FD_ISSET (fd, &wset) || FD_ISSET (fd, &xset)) {
- error (g, "fd %d is already registered", fd);
- return -1;
- }
+ /* Reduce the size of the outgoing message buffer to the real length. */
+ msg_out = safe_realloc (g, msg_out, len + 4);
+ msg_out_size = len + 4;
- if (cb == NULL) {
- error (g, "callback is NULL");
- return -1;
- }
+ xdrmem_create (&xdr, msg_out, 4, XDR_ENCODE);
+ xdr_uint32_t (&xdr, &len);
- 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);
+ r = send_to_daemon (g, msg_out, msg_out_size);
- if (fd > max_fd) {
- max_fd = fd;
- handle_cb_data = safe_realloc (g, handle_cb_data,
- sizeof (struct handle_cb_data) * (max_fd+1));
+ /* Did the daemon send a cancellation message? */
+ if (r == -2) {
+ if (g->verbose)
+ fprintf (stderr, "got daemon cancellation\n");
+ return -2;
}
- handle_cb_data[fd].cb = cb;
- handle_cb_data[fd].data = data;
- nr_fds++;
+ if (r == -1)
+ goto cleanup1;
+
+ free (msg_out);
+
+ return 0;
- /* Any integer >= 0 can be the handle, and this is as good as any ... */
- return fd;
+ cleanup1:
+ free (msg_out);
+ return -1;
}
-static int
-select_remove_handle (guestfs_h *g, int fd)
+/* Receive a reply. */
+int
+guestfs___recv (guestfs_h *g, const char *fn,
+ guestfs_message_header *hdr,
+ guestfs_message_error *err,
+ xdrproc_t xdrp, char *ret)
{
- select_init ();
+ XDR xdr;
+ void *buf;
+ uint32_t size;
+ int r;
- if (fd < 0 || fd >= FD_SETSIZE) {
- error (g, "fd %d is out of range", fd);
+ again:
+ r = recv_from_daemon (g, &size, &buf);
+ if (r == -1)
return -1;
- }
- if (!FD_ISSET (fd, &rset) && !FD_ISSET (fd, &wset) && !FD_ISSET (fd, &xset)) {
- error (g, "fd %d was not registered", fd);
+ /* 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 (size == GUESTFS_CANCEL_FLAG)
+ goto again;
+
+ if (size == GUESTFS_LAUNCH_FLAG) {
+ error (g, "%s: received unexpected launch flag from daemon when expecting reply", fn);
return -1;
}
- FD_CLR (fd, &rset);
- FD_CLR (fd, &wset);
- FD_CLR (fd, &xset);
+ xdrmem_create (&xdr, buf, size, XDR_DECODE);
- if (fd == max_fd) {
- max_fd--;
- handle_cb_data = safe_realloc (g, handle_cb_data,
- sizeof (struct handle_cb_data) * (max_fd+1));
+ if (!xdr_guestfs_message_header (&xdr, hdr)) {
+ error (g, "%s: failed to parse reply header", fn);
+ xdr_destroy (&xdr);
+ free (buf);
+ return -1;
}
-
- nr_fds--;
+ if (hdr->status == GUESTFS_STATUS_ERROR) {
+ if (!xdr_guestfs_message_error (&xdr, err)) {
+ error (g, "%s: failed to parse reply error", fn);
+ xdr_destroy (&xdr);
+ free (buf);
+ return -1;
+ }
+ } else {
+ if (xdrp && ret && !xdrp (&xdr, ret)) {
+ error (g, "%s: failed to parse reply", fn);
+ xdr_destroy (&xdr);
+ free (buf);
+ return -1;
+ }
+ }
+ xdr_destroy (&xdr);
+ free (buf);
return 0;
}
-static int
-select_add_timeout (guestfs_h *g, int interval,
- guestfs_handle_timeout_cb cb, void *data)
-{
- select_init ();
+/* Receive a file. */
- abort (); /* XXX not implemented yet */
-}
+/* Returns -1 = error, 0 = EOF, > 0 = more data */
+static ssize_t receive_file_data (guestfs_h *g, void **buf);
-static int
-select_remove_timeout (guestfs_h *g, int timer)
+int
+guestfs___recv_file (guestfs_h *g, const char *filename)
{
- select_init ();
+ 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 (g, &buf)) > 0) {
+ if (xwrite (fd, buf, r) == -1) {
+ perrorf (g, "%s: write", filename);
+ free (buf);
+ goto cancel;
+ }
+ free (buf);
+ }
- abort (); /* XXX not implemented yet */
-}
+ if (r == -1) {
+ error (g, _("%s: error in chunked encoding"), filename);
+ return -1;
+ }
-/* Note that main loops can be nested. */
-static int level = 0;
+ if (close (fd) == -1) {
+ perrorf (g, "close: %s", filename);
+ return -1;
+ }
-static void
-select_main_loop_run (guestfs_h *g)
-{
- int old_level, fd, r, events;
- fd_set rset2, wset2, xset2;
+ return 0;
- select_init ();
+ 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;
- old_level = level++;
- while (level > old_level) {
- if (nr_fds == 0) {
- level = old_level;
- break;
- }
+ if (g->verbose)
+ fprintf (stderr, "%s: waiting for daemon to acknowledge cancellation\n",
+ __func__);
- 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;
- }
+ xdrmem_create (&xdr, fbuf, sizeof fbuf, XDR_ENCODE);
+ xdr_uint32_t (&xdr, &flag);
+ xdr_destroy (&xdr);
- 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);
- }
- }
+ if (xwrite (g->sock, fbuf, sizeof fbuf) == -1) {
+ perrorf (g, _("write to daemon socket"));
+ return -1;
}
+
+ while (receive_file_data (g, NULL) > 0)
+ ; /* just discard it */
+
+ return -1;
}
-static void
-select_main_loop_quit (guestfs_h *g)
+/* Receive a chunk of file data. */
+/* Returns -1 = error, 0 = EOF, > 0 = more data */
+static ssize_t
+receive_file_data (guestfs_h *g, void **buf_r)
{
- select_init ();
+ int r;
+ void *buf;
+ uint32_t len;
+ XDR xdr;
+ guestfs_chunk chunk;
- if (level == 0) {
- error (g, "cannot quit, we are not in a main loop");
- return;
+ r = recv_from_daemon (g, &len, &buf);
+ if (r == -1) {
+ error (g, _("receive_file_data: parse error in reply callback"));
+ return -1;
+ }
+
+ if (len == GUESTFS_LAUNCH_FLAG || len == GUESTFS_CANCEL_FLAG) {
+ error (g, _("receive_file_data: unexpected flag received when reading file chunks"));
+ return -1;
+ }
+
+ memset (&chunk, 0, sizeof chunk);
+
+ xdrmem_create (&xdr, buf, len, XDR_DECODE);
+ if (!xdr_guestfs_chunk (&xdr, &chunk)) {
+ error (g, _("failed to parse file chunk"));
+ free (buf);
+ return -1;
+ }
+ xdr_destroy (&xdr);
+ /* After decoding, the original buffer is no longer used. */
+ free (buf);
+
+ if (chunk.cancel) {
+ error (g, _("file receive cancelled by daemon"));
+ free (chunk.data.data_val);
+ return -1;
+ }
+
+ if (chunk.data.data_len == 0) { /* end of transfer */
+ free (chunk.data.data_val);
+ return 0;
}
- level--;
+ if (buf_r) *buf_r = chunk.data.data_val;
+ else free (chunk.data.data_val); /* else caller frees */
+
+ return chunk.data.data_len;
}