This call provides the way to get minimum size of filesystem. This is needed for shrinking. The return units are bytes. --- daemon/Makefile.am | 1 + daemon/daemon.h | 1 + daemon/fs-min-size.c | 46 ++++++++++++++++++++++++++++++++ daemon/ntfs.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++++ generator/actions.ml | 16 +++++++++++ po/POTFILES | 1 + src/MAX_PROC_NR | 2 +- 7 files changed, 141 insertions(+), 1 deletion(-) create mode 100644 daemon/fs-min-size.c diff --git a/daemon/Makefile.am b/daemon/Makefile.am index 4ea3c88..0a01a24 100644 --- a/daemon/Makefile.am +++ b/daemon/Makefile.am @@ -116,6 +116,7 @@ guestfsd_SOURCES = \ findfs.c \ fill.c \ find.c \ + fs-min-size.c \ fsck.c \ fstrim.c \ glob.c \ diff --git a/daemon/daemon.h b/daemon/daemon.h index 508691a..a690152 100644 --- a/daemon/daemon.h +++ b/daemon/daemon.h @@ -283,6 +283,7 @@ extern int btrfs_set_uuid_random (const char *device); /*-- in ntfs.c --*/ extern char *ntfs_get_label (const char *device); extern int ntfs_set_label (const char *device, const char *label); +extern int64_t ntfs_min_size (const char *device); /*-- in swap.c --*/ extern int swap_set_uuid (const char *device, const char *uuid); diff --git a/daemon/fs-min-size.c b/daemon/fs-min-size.c new file mode 100644 index 0000000..9c107d1 --- /dev/null +++ b/daemon/fs-min-size.c @@ -0,0 +1,46 @@ +/* libguestfs - the guestfsd daemon + * Copyright (C) 2015 Maxim Perevedentsev mperevedentsev(a)virtuozzo.com + * + * 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 <unistd.h> + +#include "daemon.h" +#include "actions.h" + +int64_t +do_vfs_min_size(const mountable_t *mountable) +{ + int64_t r; + + /* How we set the label depends on the filesystem type. */ + CLEANUP_FREE char *vfs_type = do_vfs_type (mountable); + if (vfs_type == NULL) + return -1; + + else if (STREQ (vfs_type, "ntfs")) + r = ntfs_min_size (mountable->device); + + else + NOT_SUPPORTED (-1, "don't know how to get minimum size of '%s' filesystems", + vfs_type); + + return r; +} diff --git a/daemon/ntfs.c b/daemon/ntfs.c index 1ead159..b9a645a 100644 --- a/daemon/ntfs.c +++ b/daemon/ntfs.c @@ -153,6 +153,81 @@ do_ntfsresize_size (const char *device, int64_t size) return do_ntfsresize (device, size, 0); } +int64_t +ntfs_min_size (const char *device) +{ + CLEANUP_FREE char *err = NULL, *out = NULL; + CLEANUP_FREE_STRING_LIST char **lines = NULL; + int r; + size_t i; + char *p; + int64_t ret, volume_size = 0; + const char *size_pattern = "You might resize at ", + *full_pattern = "Volume is full", + *cluster_size_pattern = "Cluster size", + *volume_size_pattern = "Current volume size:"; + int is_full = 0; + int32_t cluster_size = 0; + + /* FS may be marked for check, so force ntfsresize */ + r = command (&out, &err, str_ntfsresize, "--info", "-ff", device, NULL); + + lines = split_lines (out); + if (lines == NULL) + return -1; + + if (verbose) { + for (i = 0; lines[i] != NULL; ++i) + fprintf (stderr, "ntfs_min_size: lines[%zu] = \"%s\"\n", i, lines[i]); + } + + if (r == -1) { + /* If volume is full, ntfsresize returns error. */ + for (i = 0; lines[i] != NULL; ++i) { + if (strstr (lines[i], full_pattern)) + is_full = 1; + else if ((p = strstr (lines[i], cluster_size_pattern))) { + if (sscanf (p + strlen(cluster_size_pattern), + "%*[ ]:%" SCNd32, &cluster_size) != 1) { + reply_with_error("Cannot parse cluster size"); + return -1; + } + } + else if ((p = strstr (lines[i], volume_size_pattern))) { + if (sscanf (p + strlen(volume_size_pattern), + "%" SCNd64, &volume_size) != 1) { + reply_with_error("Cannot parse volume size"); + return -1; + } + } + } + if (is_full) { + /* Ceil to cluster size */ + if (cluster_size == 0) { + reply_with_error("Bad cluster size"); + return -1; + } + return (volume_size + cluster_size - 1) / cluster_size * cluster_size; + } + + reply_with_error ("%s", err); + return -1; + } + + for (i = 0; lines[i] != NULL; ++i) { + if ((p = strstr (lines[i], size_pattern))) { + if (sscanf (p + strlen(size_pattern), "%" SCNd64, &ret) != 1) { + reply_with_error("Cannot parse minimum size"); + return -1; + } + return ret; + } + } + + reply_with_error("Minimum size not found. Check output format:\n%s", out); + return -1; +} + /* Takes optional arguments, consult optargs_bitmask. */ int do_ntfsfix (const char *device, int clearbadsectors) diff --git a/generator/actions.ml b/generator/actions.ml index 274ef3f..0646a16 100644 --- a/generator/actions.ml +++ b/generator/actions.ml @@ -12765,6 +12765,22 @@ Get the estimated minimum filesystem size of an ext2/3/4 filesystem in blocks. See also L<resize2fs(8)>." }; + { defaults with + name = "vfs_min_size"; added = (1, 31, 18); + style = RInt64 "sizeinbytes", [Mountable "mountable"], []; + proc_nr = Some 458; + tests = [ + InitPartition, IfAvailable "ntfsprogs", TestRun( + [["mkfs"; "ntfs"; "/dev/sda1"; ""; "NOARG"; ""; ""; "NOARG"]; + ["vfs_min_size"; "/dev/sda1"]]), []; + ]; + shortdesc = "get minimum filesystem size"; + longdesc = "\ +Get the minimum size of filesystem in bytes. +This is the minimum possible size for filesystem shrinking. + +See also L<ntfsresize(8)>." }; + ] (* Non-API meta-commands available only in guestfish. diff --git a/po/POTFILES b/po/POTFILES index cd2c437..d90772a 100644 --- a/po/POTFILES +++ b/po/POTFILES @@ -49,6 +49,7 @@ daemon/file.c daemon/fill.c daemon/find.c daemon/findfs.c +daemon/fs-min-size.c daemon/fsck.c daemon/fstrim.c daemon/glob.c diff --git a/src/MAX_PROC_NR b/src/MAX_PROC_NR index de2a00c..c92ddb6 100644 --- a/src/MAX_PROC_NR +++ b/src/MAX_PROC_NR @@ -1 +1 @@ -457 +458 -- 1.8.3.1

On 10/19/2015 07:45 PM, Pino Toscano wrote: Neither can I. Current name, at least, gives a hint about what is inside. FS size is not so straightforward. -- Your sincerely, Maxim Perevedentsev

On Monday 19 October 2015 17:05:03 Maxim Perevedentsev wrote: This works, yes, although maybe there should be a way to run tune2fs -l and traverse its output to either build a return hash (i.e. what do_tune2fs_l currently does) or just lookup one or more keys (like needed here). Please use STREQ, like use everywhere else in libguestfs. (and the extra brackets are not needed) This could use a simplier xstrtoul/xstrtoull. "missing 'Block size' in tune2fs_l output" STRPREFIX here. Ditto (xstrtoul). Might better check ret for possible overflows before multiplying it with block_size. Thanks, -- Pino Toscano