[Libguestfs] [PATCH] New API: resize2fs_P

Added support for getting ext2/3/4 filesystem minimum size. This is needed primarily for shrinking images. --- daemon/ext2.c | 35 +++++++++++++++++++++++++++++++++++ generator/actions.ml | 10 ++++++++++ src/MAX_PROC_NR | 2 +- 3 files changed, 46 insertions(+), 1 deletion(-) diff --git a/daemon/ext2.c b/daemon/ext2.c index ebaf0f0..3dae40f 100644 --- a/daemon/ext2.c +++ b/daemon/ext2.c @@ -279,6 +279,41 @@ do_resize2fs_M (const char *device) return 0; } +int64_t +do_resize2fs_P (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; + char pattern[] = "Estimated minimum size of the filesystem: "; + + r = command (&out, &err, str_resize2fs, "-P", device, NULL); + if (r == -1) { + reply_with_error ("%s", err); + return -1; + } + + lines = split_lines (out); + if (lines == NULL) + return -1; + + for (i = 0; lines[i] != NULL; ++i) { + if (verbose) + fprintf (stderr, "resize2fs-P: lines[%zu] = \"%s\"\n", i, lines[i]); + + if ((p = strstr (lines[i], pattern))) { + if (sscanf (p + strlen(pattern), "%" SCNu64, &ret) != 1) + return -1; + return ret; + } + } + + return -1; +} + /* Takes optional arguments, consult optargs_bitmask. */ int do_e2fsck (const char *device, diff --git a/generator/actions.ml b/generator/actions.ml index a76b466..7e2bfac 100644 --- a/generator/actions.ml +++ b/generator/actions.ml @@ -12751,6 +12751,16 @@ Only some filesystem types support setting UUIDs. To read the UUID on a filesystem, call C<guestfs_vfs_uuid>." }; + { defaults with + name = "resize2fs_P"; added = (1, 31, 17); + style = RInt64 "sizeinblocks", [Device "device"], []; + proc_nr = Some 457; + shortdesc = "get minimum filesystem size in blocks"; + longdesc = "\ +Get the minimum filesystem size in blocks. + +See also L<resize2fs(8)>." }; + ] (* Non-API meta-commands available only in guestfish. diff --git a/src/MAX_PROC_NR b/src/MAX_PROC_NR index 8d38505..de2a00c 100644 --- a/src/MAX_PROC_NR +++ b/src/MAX_PROC_NR @@ -1 +1 @@ -456 +457 -- 1.8.3.1