[Libguestfs] [PATCH v7 26/29] daemon: Reimplement ‘part_get_parttype’, ‘part_get_gpt_type’, ‘part_get_gpt_guid’ APIs in OCaml.
Richard W.M. Jones
rjones at redhat.com
Mon Jun 19 15:39:51 UTC 2017
---
daemon/parted.c | 176 +++++-----------------------------------------
daemon/parted.ml | 74 ++++++++++++++++++-
daemon/parted.mli | 5 ++
generator/actions_core.ml | 3 +
4 files changed, 96 insertions(+), 162 deletions(-)
diff --git a/daemon/parted.c b/daemon/parted.c
index 125aec60b..1c81cd968 100644
--- a/daemon/parted.c
+++ b/daemon/parted.c
@@ -348,45 +348,6 @@ print_partition_table (const char *device, bool add_m_option)
return out;
}
-char *
-do_part_get_parttype (const char *device)
-{
- CLEANUP_FREE char *out = print_partition_table (device, true);
- if (!out)
- return NULL;
-
- CLEANUP_FREE_STRING_LIST char **lines = split_lines (out);
- if (!lines)
- return NULL;
-
- if (lines[0] == NULL || STRNEQ (lines[0], "BYT;")) {
- reply_with_error ("unknown signature, expected \"BYT;\" as first line of the output: %s",
- lines[0] ? lines[0] : "(signature was null)");
- return NULL;
- }
-
- if (lines[1] == NULL) {
- reply_with_error ("parted didn't return a line describing the device");
- return NULL;
- }
-
- /* lines[1] is something like:
- * "/dev/sda:1953525168s:scsi:512:512:msdos:ATA Hitachi HDT72101;"
- */
- char *r = get_table_field (lines[1], 5);
- if (r == NULL)
- return NULL;
-
- /* If "loop" return an error (RHBZ#634246). */
- if (STREQ (r, "loop")) {
- free (r);
- reply_with_error ("not a partitioned device");
- return NULL;
- }
-
- return r;
-}
-
int
do_part_get_bootable (const char *device, int partnum)
{
@@ -557,126 +518,6 @@ do_part_set_gpt_guid (const char *device, int partnum, const char *guid)
return 0;
}
-static char *
-sgdisk_info_extract_field (const char *device, int partnum, const char *field,
- char *(*extract) (const char *path))
-{
- if (partnum <= 0) {
- reply_with_error ("partition number must be >= 1");
- return NULL;
- }
-
- CLEANUP_FREE char *partnum_str = NULL;
- if (asprintf (&partnum_str, "%i", partnum) == -1) {
- reply_with_perror ("asprintf");
- return NULL;
- }
-
- udev_settle ();
-
- CLEANUP_FREE char *err = NULL;
- int r = commandf (NULL, &err, COMMAND_FLAG_FOLD_STDOUT_ON_STDERR,
- str_sgdisk, device, "-i", partnum_str, NULL);
-
- if (r == -1) {
- reply_with_error ("%s %s -i %s: %s", str_sgdisk, device, partnum_str, err);
- return NULL;
- }
-
- udev_settle ();
-
- CLEANUP_FREE_STRING_LIST char **lines = split_lines (err);
- if (lines == NULL) {
- reply_with_error ("'%s %s -i %i' returned no output",
- str_sgdisk, device, partnum);
- return NULL;
- }
-
- const int fieldlen = strlen (field);
-
- /* Parse the output of sgdisk -i:
- * Partition GUID code: 21686148-6449-6E6F-744E-656564454649 (BIOS boot partition)
- * Partition unique GUID: 19AEC5FE-D63A-4A15-9D37-6FCBFB873DC0
- * First sector: 2048 (at 1024.0 KiB)
- * Last sector: 411647 (at 201.0 MiB)
- * Partition size: 409600 sectors (200.0 MiB)
- * Attribute flags: 0000000000000000
- * Partition name: 'EFI System Partition'
- */
- for (char **i = lines; *i != NULL; i++) {
- char *line = *i;
-
- /* Skip blank lines */
- if (line[0] == '\0') continue;
-
- /* Split the line in 2 at the colon */
- char *colon = strchr (line, ':');
- if (colon) {
- if (colon - line == fieldlen &&
- memcmp (line, field, fieldlen) == 0)
- {
- /* The value starts after the colon */
- char *value = colon + 1;
-
- /* Skip any leading whitespace */
- value += strspn (value, " \t");
-
- /* Extract the actual information from the field. */
- char *ret = extract (value);
- if (ret == NULL) {
- /* The extraction function already sends the error. */
- return NULL;
- }
-
- return ret;
- }
- } else {
- /* Ignore lines with no colon. Log to stderr so it will show up in
- * LIBGUESTFS_DEBUG. */
- if (verbose) {
- fprintf (stderr, "get-gpt-type: unexpected sgdisk output ignored: %s\n",
- line);
- }
- }
- }
-
- /* If we got here it means we didn't find the field */
- reply_with_error ("sgdisk output did not contain '%s'. "
- "See LIBGUESTFS_DEBUG output for more details", field);
- return NULL;
-}
-
-static char *
-extract_uuid (const char *value)
-{
- /* The value contains only valid GUID characters */
- const size_t value_len = strspn (value, "-0123456789ABCDEF");
-
- char *ret = malloc (value_len + 1);
- if (ret == NULL) {
- reply_with_perror ("malloc");
- return NULL;
- }
-
- memcpy (ret, value, value_len);
- ret[value_len] = '\0';
- return ret;
-}
-
-char *
-do_part_get_gpt_type (const char *device, int partnum)
-{
- return sgdisk_info_extract_field (device, partnum,
- "Partition GUID code", extract_uuid);
-}
-
-char *
-do_part_get_gpt_guid (const char *device, int partnum)
-{
- return sgdisk_info_extract_field (device, partnum,
- "Partition unique GUID", extract_uuid);
-}
-
char *
do_part_get_name (const char *device, int partnum)
{
@@ -840,6 +681,23 @@ do_part_get_mbr_part_type (const char *device, int partnum)
return NULL;
}
+static char *
+extract_uuid (const char *value)
+{
+ /* The value contains only valid GUID characters */
+ const size_t value_len = strspn (value, "-0123456789ABCDEF");
+
+ char *ret = malloc (value_len + 1);
+ if (ret == NULL) {
+ reply_with_perror ("malloc");
+ return NULL;
+ }
+
+ memcpy (ret, value, value_len);
+ ret[value_len] = '\0';
+ return ret;
+}
+
char *
do_part_get_disk_guid (const char *device)
{
diff --git a/daemon/parted.ml b/daemon/parted.ml
index 37e1b42be..7c1e577dd 100644
--- a/daemon/parted.ml
+++ b/daemon/parted.ml
@@ -81,18 +81,18 @@ let print_partition_table ~add_m_option device =
let out = String.trim out in
let lines = String.nsplit "\n" out in
- (* lines[0] is "BYT;", lines[1] is the device line which we ignore,
+ (* lines[0] is "BYT;", lines[1] is the device line,
* lines[2..] are the partitions themselves.
*)
match lines with
- | "BYT;" :: _ :: lines -> lines
+ | "BYT;" :: device_line :: lines -> device_line, lines
| [] | [_] ->
failwith "too few rows of output from 'parted print' command"
| _ ->
failwith "did not see 'BYT;' magic value in 'parted print' command"
let part_list device =
- let lines = print_partition_table ~add_m_option:true device in
+ let _, lines = print_partition_table ~add_m_option:true device in
List.map (
fun line ->
@@ -104,3 +104,71 @@ let part_list device =
failwithf "could not parse row from output of 'parted print' command: %s: %s"
line err
) lines
+
+let part_get_parttype device =
+ let device_line, _ = print_partition_table ~add_m_option:true device in
+
+ (* device_line is something like:
+ * "/dev/sda:1953525168s:scsi:512:512:msdos:ATA Hitachi HDT72101;"
+ *)
+ let fields = String.nsplit ":" device_line in
+ match fields with
+ | _::_::_::_::_::"loop"::_ -> (* If "loop" return an error (RHBZ#634246). *)
+ failwithf "%s: not a partitioned device" device
+ | _::_::_::_::_::ret::_ -> ret
+ | _ ->
+ failwithf "%s: cannot parse the output of parted" device
+
+let rec part_get_gpt_type device partnum =
+ sgdisk_info_extract_uuid_field device partnum "Partition GUID code"
+and part_get_gpt_guid device partnum =
+ sgdisk_info_extract_uuid_field device partnum "Partition unique GUID"
+
+and sgdisk_info_extract_uuid_field device partnum field =
+ if partnum <= 0 then failwith "partition number must be >= 1";
+
+ udev_settle ();
+
+ let r, _, err =
+ commandr ~flags:[CommandFlagFoldStdoutOnStderr]
+ "sgdisk" [ device; "-i"; string_of_int partnum ] in
+ if r <> 0 then
+ failwithf "sgdisk: %s" err;
+
+ udev_settle ();
+
+ let err = String.trim err in
+ let lines = String.nsplit "\n" err in
+
+ (* Parse the output of sgdisk -i:
+ * Partition GUID code: 21686148-6449-6E6F-744E-656564454649 (BIOS boot partition)
+ * Partition unique GUID: 19AEC5FE-D63A-4A15-9D37-6FCBFB873DC0
+ * First sector: 2048 (at 1024.0 KiB)
+ * Last sector: 411647 (at 201.0 MiB)
+ * Partition size: 409600 sectors (200.0 MiB)
+ * Attribute flags: 0000000000000000
+ * Partition name: 'EFI System Partition'
+ *)
+ let field_len = String.length field in
+ let rec loop = function
+ | [] ->
+ failwithf "%s: sgdisk output did not contain '%s'" device field
+ | line :: _ when String.is_prefix line field &&
+ String.length line >= field_len + 2 &&
+ line.[field_len] = ':' ->
+ let value =
+ String.sub line (field_len+1) (String.length line - field_len - 1) in
+
+ (* Skip any whitespace after the colon. *)
+ let value = String.triml value in
+
+ (* Extract the UUID. *)
+ extract_uuid value
+
+ | _ :: lines -> loop lines
+ in
+ loop lines
+
+and extract_uuid value =
+ (* The value contains only valid GUID characters. *)
+ String.sub value 0 (String.span value "-0123456789ABCDEF")
diff --git a/daemon/parted.mli b/daemon/parted.mli
index 057d7e8c7..5a77a8779 100644
--- a/daemon/parted.mli
+++ b/daemon/parted.mli
@@ -25,3 +25,8 @@ type partition = {
val part_get_mbr_id : string -> int -> int
val part_list : string -> partition list
+
+val part_get_parttype : string -> string
+
+val part_get_gpt_type : string -> int -> string
+val part_get_gpt_guid : string -> int -> string
diff --git a/generator/actions_core.ml b/generator/actions_core.ml
index 4ec83d22d..c3421133e 100644
--- a/generator/actions_core.ml
+++ b/generator/actions_core.ml
@@ -5073,6 +5073,7 @@ Size of the partition in bytes.
{ defaults with
name = "part_get_parttype"; added = (1, 0, 78);
style = RString (RPlainString, "parttype"), [String (Device, "device")], [];
+ impl = OCaml "Parted.part_get_parttype";
tests = [
InitEmpty, Always, TestResultString (
[["part_disk"; "/dev/sda"; "gpt"];
@@ -8247,6 +8248,7 @@ for a useful list of type GUIDs." };
{ defaults with
name = "part_get_gpt_type"; added = (1, 21, 1);
style = RString (RPlainString, "guid"), [String (Device, "device"); Int "partnum"], [];
+ impl = OCaml "Parted.part_get_gpt_type";
optional = Some "gdisk";
tests = [
InitGPT, Always, TestResultString (
@@ -9067,6 +9069,7 @@ valid GUID." };
{ defaults with
name = "part_get_gpt_guid"; added = (1, 29, 25);
style = RString (RPlainString, "guid"), [String (Device, "device"); Int "partnum"], [];
+ impl = OCaml "Parted.part_get_gpt_guid";
optional = Some "gdisk";
tests = [
InitGPT, Always, TestResultString (
--
2.13.0
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