/* Run uml_mkcow to create a COW overlay. */
static char *
make_cow_overlay (guestfs_h *g, const char *original)
{
CLEANUP_CMD_CLOSE struct command *cmd = guestfs_int_new_command (g);
char *overlay;
int r;
if (guestfs_int_lazy_make_tmpdir (g) == -1)
return NULL;
overlay = safe_asprintf (g, "%s/overlay%d", g->tmpdir, g->unique++);
guestfs_int_cmd_add_arg (cmd, "uml_mkcow");
guestfs_int_cmd_add_arg (cmd, overlay);
guestfs_int_cmd_add_arg (cmd, original);
r = guestfs_int_cmd_run (cmd);
if (r == -1) {
free (overlay);
return NULL;
}
if (!WIFEXITED (r) || WEXITSTATUS (r) != 0) {
guestfs_int_external_command_failed (g, r, "uml_mkcow", original);
free (overlay);
return NULL;
}
return overlay;
}
static int
write_or_append (guestfs_h *g, const char *path,
const char *content, size_t size,
int append)
{
CLEANUP_UNLINK_FREE char *tmpfile = NULL;
int fd = -1;
int64_t filesize;
/* If the content is small enough, use guestfs_internal_write{,_append}
* since that call is more efficient.
*/
if (size <= 2*1024*1024)
return
(!append ? guestfs_internal_write : guestfs_internal_write_append)
(g, path, content, size);
if (guestfs_int_lazy_make_tmpdir (g) == -1)
goto err;
/* Write the content out to a temporary file. */
tmpfile = safe_asprintf (g, "%s/write%d", g->tmpdir, ++g->unique);
fd = open (tmpfile, O_WRONLY|O_CREAT|O_NOCTTY|O_CLOEXEC, 0600);
if (fd == -1) {
perrorf (g, "open: %s", tmpfile);
goto err;
}
if (full_write (fd, content, size) != size) {
perrorf (g, "write: %s", tmpfile);
goto err;
}
if (close (fd) == -1) {
perrorf (g, "close: %s", tmpfile);
goto err;
}
fd = -1;
if (!append) {
if (guestfs_upload (g, tmpfile, path) == -1)
goto err;
}
else {
/* XXX Should have an 'upload-append' call to make this atomic. */
filesize = guestfs_filesize (g, path);
if (filesize == -1)
goto err;
if (guestfs_upload_offset (g, tmpfile, path, filesize) == -1)
goto err;
}
return 0;
err:
if (fd >= 0)
close (fd);
return -1;
}
int
guestfs_impl_launch (guestfs_h *g)
{
/* Configured? */
if (g->state != CONFIG) {
error (g, _("the libguestfs handle has already been launched"));
return -1;
}
/* Start the clock ... */
gettimeofday (&g->launch_t, NULL);
TRACE0 (launch_start);
/* Make the temporary directory. */
if (guestfs_int_lazy_make_tmpdir (g) == -1)
return -1;
/* Some common debugging information. */
if (g->verbose) {
CLEANUP_FREE_VERSION struct guestfs_version *v =
guestfs_version (g);
struct backend *b;
CLEANUP_FREE char *backend = guestfs_get_backend (g);
int mask;
debug (g, "launch: program=%s", g->program);
if (STRNEQ (g->identifier, ""))
debug (g, "launch: identifier=%s", g->identifier);
debug (g, "launch: version=%"PRIi64".%"PRIi64".%"PRIi64"%s",
v->major, v->minor, v->release, v->extra);
for (b = backends; b != NULL; b = b->next)
debug (g, "launch: backend registered: %s", b->name);
debug (g, "launch: backend=%s", backend);
debug (g, "launch: tmpdir=%s", g->tmpdir);
mask = guestfs_int_getumask (g);
if (mask >= 0)
debug (g, "launch: umask=0%03o", (unsigned) mask);
debug (g, "launch: euid=%ju", (uintmax_t) geteuid ());
}
/* Launch the appliance. */
if (g->backend_ops->launch (g, g->backend_data, g->backend_arg) == -1)
return -1;
return 0;
}
char *
guestfs_impl_read_file (guestfs_h *g, const char *path, size_t *size_r)
{
int fd = -1;
size_t size;
CLEANUP_UNLINK_FREE char *tmpfile = NULL;
char *ret = NULL;
struct stat statbuf;
if (guestfs_int_lazy_make_tmpdir (g) == -1)
goto err;
tmpfile = safe_asprintf (g, "%s/cat%d", g->tmpdir, ++g->unique);
if (guestfs_download (g, path, tmpfile) == -1)
goto err;
fd = open (tmpfile, O_RDONLY|O_CLOEXEC);
if (fd == -1) {
perrorf (g, "open: %s", tmpfile);
goto err;
}
/* Read the whole file into memory. */
if (fstat (fd, &statbuf) == -1) {
perrorf (g, "stat: %s", tmpfile);
goto err;
}
/* Don't use safe_malloc, because we want to return an errno to the caller. */
size = statbuf.st_size;
ret = malloc (size + 1);
if (!ret) {
perrorf (g, "malloc: %zu bytes", size + 1);
goto err;
}
if (full_read (fd, ret, size) != size) {
perrorf (g, "full-read: %s: %zu bytes", tmpfile, size + 1);
goto err;
}
ret[size] = '\0';
if (close (fd) == -1) {
perrorf (g, "close: %s", tmpfile);
goto err;
}
/* Mustn't touch *size_r until we are sure that we won't return any
* error (RHBZ#589039).
*/
*size_r = size;
return ret;
err:
free (ret);
if (fd >= 0)
close (fd);
return NULL;
}
