Re: [Libguestfs] [PATCH 5/6] New APIs: copy-in and copy-out

On Mon, Jan 26, 2015 at 05:04:10PM +0100, Pino Toscano wrote: > Currently implemented as guestfish commands, provide them instead as > single source -> destination functions for the library, so they can be > used also in other places. > > These functions are not added to guestfish, since guestfish has its own > implementation (which will soon switch to call copy-in and copy-out for > multiple paths). > --- > generator/actions.ml | 28 ++++++ > po/POTFILES | 1 + > src/Makefile.am | 1 + > src/copy-in-out.c | 244 +++++++++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 274 insertions(+) > create mode 100644 src/copy-in-out.c > > diff --git a/generator/actions.ml b/generator/actions.ml > index 25f4bb5..ab97891 100644 > --- a/generator/actions.ml > +++ b/generator/actions.ml > @@ -3310,6 +3310,34 @@ In non-C language bindings, this allows you to retrieve the underlying > C pointer to the handle (ie. C<guestfs_h *>). The purpose of this is > to allow other libraries to interwork with libguestfs." }; > > + { defaults with > + name = "copy_in"; > + style = RErr, [String "localpath"; Pathname "remotedir"], []; > + visibility = VPublicNoFish; > + shortdesc = "copy local files or directories into an image"; > + longdesc = "\ > +C<guestfs_copy_in> copies local files or directories recursively into > +the disk image, placing them in the directory called C</remotedir> ^ You don't need the / here.

> +(which must exist). > + > +Wildcards cannot be used." }; > + > + { defaults with > + name = "copy_out"; > + style = RErr, [Pathname "remotepath"; String "localdir"], []; > + visibility = VPublicNoFish; > + shortdesc = "copy remote files or directories out of an image"; > + longdesc = "\ > +C<guestfs_copy_out> copies remote files or directories recursively > +out of the disk image, placing them on the host disk in a local > +directory called C<localdir> (which must exist). > + > +To download to the current directory, use C<.> as in: > + > + C<guestfs_copy_out> /home . > + > +Wildcards cannot be used." }; > + > ] > > (* daemon_functions are any functions which cause some action > diff --git a/po/POTFILES b/po/POTFILES > index 4194e5f..6e65377 100644 > --- a/po/POTFILES > +++ b/po/POTFILES > @@ -297,6 +297,7 @@ src/canonical-name.c > src/cleanup.c > src/command.c > src/conn-socket.c > +src/copy-in-out.c > src/create.c > src/dbdump.c > src/drives.c > diff --git a/src/Makefile.am b/src/Makefile.am > index a83f257..2496887 100644 > --- a/src/Makefile.am > +++ b/src/Makefile.am > @@ -90,6 +90,7 @@ libguestfs_la_SOURCES = \ > canonical-name.c \ > command.c \ > conn-socket.c \ > + copy-in-out.c \ > create.c \ > dbdump.c \ > drives.c \ > diff --git a/src/copy-in-out.c b/src/copy-in-out.c > new file mode 100644 > index 0000000..8e2edd3 > --- /dev/null > +++ b/src/copy-in-out.c > @@ -0,0 +1,244 @@ > +/* libguestfs > + * Copyright (C) 2015 Red Hat Inc. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the Free Software > + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. > + */ > + > +#include <config.h> > + > +#include <stdio.h> > +#include <stdlib.h> > +#include <stdint.h> > +#include <inttypes.h> > +#include <unistd.h> > +#include <sys/types.h> > +#include <sys/stat.h> > +#include <sys/wait.h> > +#include <errno.h> > +#include <string.h> > + > +#include "guestfs.h" > +#include "guestfs-internal.h" > +#include "guestfs-internal-actions.h" > + > +static int split_path (char *buf, size_t buf_size, const char *path, const char **dirname, const char **basename); > + > +int > +guestfs__copy_in (guestfs_h *g, const char *localpath, const char *remotedir) > +{ > + CLEANUP_CMD_CLOSE struct command *cmd = guestfs___new_command (g); > + int fd; > + int r; > + char fdbuf[64]; > + size_t buf_len = strlen (localpath) + 1; > + char buf[buf_len]; > + const char *dirname, *basename; > + > + if (guestfs_is_dir (g, remotedir) == -1) > + return -1; I suppose this is here to check that remotedir is a directory, but that's not what the code here does. The original guestfish code is: int remote_is_dir = guestfs_is_dir (g, remote); if (remote_is_dir == -1) return -1; if (!remote_is_dir) { fprintf (stderr, _("copy-in: target '%s' is not a directory\n"), remote); return -1; }

> + if (split_path (buf, buf_len, localpath, &dirname, &basename) == -1) > + return -1; > + > + guestfs___cmd_add_arg (cmd, "tar"); > + if (dirname) { > + guestfs___cmd_add_arg (cmd, "-C"); > + guestfs___cmd_add_arg (cmd, dirname); > + } > + guestfs___cmd_add_arg (cmd, "-cf"); > + guestfs___cmd_add_arg (cmd, "-"); > + guestfs___cmd_add_arg (cmd, basename); > + > + r = guestfs___cmd_run_async (cmd, NULL, NULL, &fd, NULL); > + if (r == -1) > + return -1; > + > + snprintf (fdbuf, sizeof fdbuf, "/dev/fd/%d", fd); > + > + r = guestfs_tar_in (g, fdbuf, remotedir); > + > + if (close (fd) == -1) { > + perror ("close (tar subprocess)"); > + return -1; > + } > + > + r = guestfs___cmd_wait (cmd); > + if (r == -1) > + return -1; > + if (!(WIFEXITED (r) && WEXITSTATUS (r) == 0)) > + return -1; > + > + return 0; > +} > + > +struct copy_out_child_data { > + const char *localdir; > + const char *basename; > +}; > + > +static int > +child_setup (guestfs_h *g, void *data) > +{ > + struct copy_out_child_data d = *(struct copy_out_child_data *) data; > + > + if (chdir (d.localdir) == -1) { > + perror (d.localdir); > + return -1; > + } > + > + if (mkdir (d.basename, 0777) == -1 && errno != EEXIST) { > + perror (d.basename); > + return -1; > + } > + > + if (chdir (d.basename) == -1) { > + perror (d.basename); > + return -1; > + } > + > + return 0; > +} > + > +int > +guestfs__copy_out (guestfs_h *g, const char *remotepath, const char *localdir) > +{ > + struct stat statbuf; > + int r; > + > + if (stat (localdir, &statbuf) == -1 || > + ! (S_ISDIR (statbuf.st_mode))) { > + error (g, _("target '%s' is not a directory"), localdir); > + return -1; > + } > + > + /* If the remote is a file, download it. If it's a directory, > + * create the directory in localdir first before using tar-out. > + */ > + r = guestfs_is_file (g, remotepath); > + if (r == -1) > + return -1; > + > + if (r == 1) { /* is file */ > + CLEANUP_FREE char *filename = NULL; > + size_t buf_len = strlen (remotepath) + 1; > + char buf[buf_len]; > + const char *basename; > + > + if (split_path (buf, buf_len, remotepath, NULL, &basename) == -1) > + return -1; > + > + if (asprintf (&filename, "%s/%s", localdir, basename) == -1) { > + perror ("asprintf"); > + return -1; > + } > + if (guestfs_download (g, remotepath, filename) == -1) > + return -1; > + } else { /* not a regular file */ > + CLEANUP_CMD_CLOSE struct command *cmd = guestfs___new_command (g); > + struct copy_out_child_data data; > + char fdbuf[64]; > + int fd; > + > + r = guestfs_is_dir (g, remotepath); > + if (r == -1) > + return -1; > + > + if (r == 0) { > + error (g, _("'%s' is not a file or directory"), remotepath); > + return -1; > + } > + > + size_t buf_len = strlen (remotepath) + 1; > + char buf[buf_len]; > + const char *basename; > + if (split_path (buf, buf_len, remotepath, NULL, &basename) == -1) > + return -1; > + > + /* RHBZ#845522: If remotepath == "/" then basename would be an empty > + * string. Replace it with "." so that make_tar_output writes > + * to "localdir/." > + */ > + if (STREQ (basename, "")) > + basename = "."; > + > + data.localdir = localdir; > + data.basename = basename; > + > + guestfs___cmd_set_child_callback (cmd, &child_setup, &data); > + > + guestfs___cmd_add_arg (cmd, "tar"); > + guestfs___cmd_add_arg (cmd, "-xf"); > + guestfs___cmd_add_arg (cmd, "-"); > + > + r = guestfs___cmd_run_async (cmd, NULL, &fd, NULL, NULL); > + if (r == -1) > + return -1; > + > + snprintf (fdbuf, sizeof fdbuf, "/dev/fd/%d", fd); > + > + r = guestfs_tar_out (g, remotepath, fdbuf); > + > + if (close (fd) == -1) { > + perror ("close (tar-output subprocess)"); > + return -1; > + } > + > + r = guestfs___cmd_wait (cmd); > + if (r == -1) > + return -1; > + if (!(WIFEXITED (r) && WEXITSTATUS (r) == 0)) > + return -1; > + } > + > + return 0; > +} > + > +/* Split path into directory name and base name, using the buffer > + * provided as a working area. If there is no directory name > + * (eg. path == "/") then this can return dirname as NULL. > + */ > +static int > +split_path (char *buf, size_t buf_size, > + const char *path, const char **dirname, const char **basename) > +{ > + size_t len = strlen (path); > + if (len == 0 || len > buf_size - 1) { > + fprintf (stderr, _("error: argument is zero length or longer than maximum permitted\n")); > + return -1; > + } > + > + strcpy (buf, path); > + > + if (len >= 2 && buf[len-1] == '/') { > + buf[len-1] = '\0'; > + len--; > + } > + > + char *p = strrchr (buf, '/'); > + if (p && p > buf) { /* "foo/bar" */ > + *p = '\0'; > + p++; > + if (dirname) *dirname = buf; > + if (basename) *basename = p; > + } else if (p && p == buf) { /* "/foo" */ > + if (dirname) *dirname = "/"; > + if (basename) *basename = buf+1; > + } else { > + if (dirname) *dirname = NULL; > + if (basename) *basename = buf; > + } > + > + return 0; > +} The guestfish code (which took *ages* to get right) is a lot more complicated ...