[Libguestfs] [PATCH v2 13/23] daemon: Reimplement ‘lvs’ API in OCaml.
Richard W.M. Jones
rjones at redhat.com
Fri Jul 21 20:36:17 UTC 2017
---
daemon/Makefile.am | 2 +
daemon/lvm.c | 151 ----------------------------------------------
daemon/lvm.ml | 98 ++++++++++++++++++++++++++++++
daemon/lvm.mli | 19 ++++++
generator/actions_core.ml | 1 +
5 files changed, 120 insertions(+), 151 deletions(-)
diff --git a/daemon/Makefile.am b/daemon/Makefile.am
index f1ab10c6e..2a8e5876a 100644
--- a/daemon/Makefile.am
+++ b/daemon/Makefile.am
@@ -251,6 +251,7 @@ SOURCES_MLI = \
is.mli \
ldm.mli \
link.mli \
+ lvm.mli \
mount.mli \
mountable.mli \
parted.mli \
@@ -271,6 +272,7 @@ SOURCES_ML = \
is.ml \
ldm.ml \
link.ml \
+ lvm.ml \
mount.ml \
parted.ml \
realpath.ml \
diff --git a/daemon/lvm.c b/daemon/lvm.c
index 5d12b009f..072bf53b4 100644
--- a/daemon/lvm.c
+++ b/daemon/lvm.c
@@ -103,89 +103,6 @@ convert_lvm_output (char *out, const char *prefix)
return take_stringsbuf (&ret);
}
-/* Filter a colon-separated output of
- * lvs -o lv_attr,vg_name,lv_name
- * removing thin layouts, and building the device path as we expect it.
- *
- * This is used only when lvm has no -S.
- */
-static char **
-filter_convert_old_lvs_output (char *out)
-{
- char *p, *pend;
- CLEANUP_FREE_STRINGSBUF DECLARE_STRINGSBUF (ret);
-
- p = out;
- while (p) {
- size_t len;
- char *saveptr;
- char *lv_attr, *vg_name, *lv_name;
-
- pend = strchr (p, '\n'); /* Get the next line of output. */
- if (pend) {
- *pend = '\0';
- pend++;
- }
-
- while (*p && c_isspace (*p)) /* Skip any leading whitespace. */
- p++;
-
- /* Sigh, skip trailing whitespace too. "pvs", I'm looking at you. */
- len = strlen (p)-1;
- while (*p && c_isspace (p[len]))
- p[len--] = '\0';
-
- if (!*p) { /* Empty line? Skip it. */
- skip_line:
- p = pend;
- continue;
- }
-
- lv_attr = strtok_r (p, ":", &saveptr);
- if (!lv_attr)
- goto skip_line;
-
- vg_name = strtok_r (NULL, ":", &saveptr);
- if (!vg_name)
- goto skip_line;
-
- lv_name = strtok_r (NULL, ":", &saveptr);
- if (!lv_name)
- goto skip_line;
-
- /* Ignore thin layouts (RHBZ#1278878). */
- if (lv_attr[0] == 't')
- goto skip_line;
-
- /* Ignore activationskip (RHBZ#1306666). */
- if (strlen (lv_attr) >= 10 && lv_attr[9] == 'k')
- goto skip_line;
-
- /* Ignore "unknown device" message (RHBZ#1054761). */
- if (STRNEQ (p, "unknown device")) {
- char buf[256];
-
- snprintf (buf, sizeof buf, "/dev/%s/%s", vg_name, lv_name);
- if (add_string (&ret, buf) == -1) {
- free (out);
- return NULL;
- }
- }
-
- p = pend;
- }
-
- free (out);
-
- if (ret.size > 0)
- sort_strings (ret.argv, ret.size);
-
- if (end_stringsbuf (&ret) == -1)
- return NULL;
-
- return take_stringsbuf (&ret);
-}
-
char **
do_pvs (void)
{
@@ -222,74 +139,6 @@ do_vgs (void)
return convert_lvm_output (out, NULL);
}
-/* Check whether lvs has -S to filter its output.
- * It is available only in lvm2 >= 2.02.107.
- */
-static int
-test_lvs_has_S_opt (void)
-{
- static int result = -1;
- if (result != -1)
- return result;
-
- CLEANUP_FREE char *out = NULL;
- CLEANUP_FREE char *err = NULL;
-
- int r = command (&out, &err, str_lvm, "lvs", "--help", NULL);
- if (r == -1) {
- reply_with_error ("lvm lvs --help: %s", err);
- return -1;
- }
-
- if (strstr (out, "-S") == NULL)
- result = 0;
- else
- result = 1;
-
- return result;
-}
-
-char **
-do_lvs (void)
-{
- char *out;
- CLEANUP_FREE char *err = NULL;
- int r;
- const int has_S = test_lvs_has_S_opt ();
-
- if (has_S < 0)
- return NULL;
-
- if (has_S > 0) {
- r = command (&out, &err,
- str_lvm, "lvs",
- "-o", "vg_name,lv_name",
- "-S", "lv_role=public && lv_skip_activation!=yes",
- "--noheadings",
- "--separator", "/", NULL);
- if (r == -1) {
- reply_with_error ("%s", err);
- free (out);
- return NULL;
- }
-
- return convert_lvm_output (out, "/dev/");
- } else {
- r = command (&out, &err,
- str_lvm, "lvs",
- "-o", "lv_attr,vg_name,lv_name",
- "--noheadings",
- "--separator", ":", NULL);
- if (r == -1) {
- reply_with_error ("%s", err);
- free (out);
- return NULL;
- }
-
- return filter_convert_old_lvs_output (out);
- }
-}
-
/* These were so complex to implement that I ended up auto-generating
* the code. That code is in stubs.c, and it is generated as usual
* by generator.ml.
diff --git a/daemon/lvm.ml b/daemon/lvm.ml
new file mode 100644
index 000000000..4a9156dad
--- /dev/null
+++ b/daemon/lvm.ml
@@ -0,0 +1,98 @@
+(* guestfs-inspection
+ * Copyright (C) 2009-2017 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.
+ *)
+
+open Printf
+
+open Std_utils
+
+open Utils
+
+(* Check whether lvs has -S to filter its output.
+ * It is available only in lvm2 >= 2.02.107.
+ *)
+let lvs_has_S_opt = lazy (
+ let out = command "lvm" ["lvs"; "--help"] in
+ String.find out "-S" >= 0
+)
+
+let rec lvs () =
+ let has_S = Lazy.force lvs_has_S_opt in
+ if has_S then (
+ let out = command "lvm" ["lvs";
+ "-o"; "vg_name,lv_name";
+ "-S"; "lv_role=public && lv_skip_activation!=yes";
+ "--noheadings";
+ "--separator"; "/"] in
+ convert_lvm_output ~prefix:"/dev/" out
+ )
+ else (
+ let out = command "lvm" ["lvs";
+ "-o"; "lv_attr,vg_name,lv_name";
+ "--noheadings";
+ "--separator"; ":"] in
+ filter_convert_old_lvs_output out
+ )
+
+and convert_lvm_output ?prefix out =
+ let lines = String.nsplit "\n" out in
+
+ (* Skip leading and trailing ("pvs", I'm looking at you) whitespace. *)
+ let lines = List.map String.trim lines in
+
+ (* Skip empty lines. *)
+ let lines = List.filter ((<>) "") lines in
+
+ (* Ignore "unknown device" message (RHBZ#1054761). *)
+ let lines = List.filter ((<>) "unknown device") lines in
+
+ (* Add a prefix? *)
+ let lines =
+ match prefix with
+ | None -> lines
+ | Some prefix -> List.map ((^) prefix) lines in
+
+ (* Sort and return. *)
+ List.sort compare lines
+
+(* Filter a colon-separated output of
+ * lvs -o lv_attr,vg_name,lv_name
+ * removing thin layouts, and building the device path as we expect it.
+ *
+ * This is used only when lvm has no -S.
+ *)
+and filter_convert_old_lvs_output out =
+ let lines = String.nsplit "\n" out in
+ let lines = List.map String.trim lines in
+ let lines = List.filter ((<>) "") lines in
+ let lines = List.filter ((<>) "unknown device") lines in
+
+ let lines = filter_map (
+ fun line ->
+ match String.nsplit ":" line with
+ | [ lv_attr; vg_name; lv_name ] ->
+ (* Ignore thin layouts (RHBZ#1278878). *)
+ if String.length lv_attr > 0 && lv_attr.[0] = 't' then None
+ (* Ignore activationskip (RHBZ#1306666). *)
+ else if String.length lv_attr > 9 && lv_attr.[9] = 'k' then None
+ else
+ Some (sprintf "/dev/%s/%s" vg_name lv_name)
+ | _ ->
+ None
+ ) lines in
+
+ List.sort compare lines
diff --git a/daemon/lvm.mli b/daemon/lvm.mli
new file mode 100644
index 000000000..f254728cb
--- /dev/null
+++ b/daemon/lvm.mli
@@ -0,0 +1,19 @@
+(* guestfs-inspection
+ * Copyright (C) 2009-2017 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.
+ *)
+
+val lvs : unit -> string list
diff --git a/generator/actions_core.ml b/generator/actions_core.ml
index 331a5feb1..f6f006eee 100644
--- a/generator/actions_core.ml
+++ b/generator/actions_core.ml
@@ -1732,6 +1732,7 @@ See also C<guestfs_vgs_full>." };
{ defaults with
name = "lvs"; added = (0, 0, 4);
style = RStringList (RDevice, "logvols"), [], [];
+ impl = OCaml "Lvm.lvs";
optional = Some "lvm2";
tests = [
InitBasicFSonLVM, Always, TestResult (
--
2.13.2
More information about the Libguestfs
mailing list