Libguestfs - Feb 2015 - [PATCH v4 0/2] add btrfs_balance_status and btrfs_scrub_status

v4:
  - add reply_with_error when nlines < 1
  - remove `i == X' tests.

v3:
  - rebase on upstream
  - fix some comments

v2:
  - add check for the length of lines[]
  - the code parsing 'btrfs scrub -R status' output is changed into a
loop


Hu Tao (2):
  New API: btrfs_balance_status
  New API: btfs_scrub_status

 daemon/btrfs.c                           | 268 +++++++++++++++++++++++++++++++
 generator/actions.ml                     |  26 +++
 generator/structs.ml                     |  34 ++++
 gobject/Makefile.inc                     |   4 +
 java/Makefile.inc                        |   2 +
 java/com/redhat/et/libguestfs/.gitignore |   2 +
 po/POTFILES                              |   2 +
 src/MAX_PROC_NR                          |   2 +-
 8 files changed, 339 insertions(+), 1 deletion(-)

-- 
2.1.0

From: Hu Tao <hutao@cn.fujitsu.com>

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
---
 daemon/btrfs.c                           | 126 +++++++++++++++++++++++++++++++
 generator/actions.ml                     |  10 +++
 generator/structs.ml                     |  12 +++
 gobject/Makefile.inc                     |   2 +
 java/Makefile.inc                        |   1 +
 java/com/redhat/et/libguestfs/.gitignore |   1 +
 po/POTFILES                              |   1 +
 src/MAX_PROC_NR                          |   2 +-
 8 files changed, 154 insertions(+), 1 deletion(-)

diff --git a/daemon/btrfs.c b/daemon/btrfs.c
index 5cab52a..a979327 100644
--- a/daemon/btrfs.c
+++ b/daemon/btrfs.c
@@ -1659,3 +1659,129 @@ do_btrfs_rescue_super_recover (const char *device)
 
   return 0;
 }
+
+guestfs_int_btrfsbalance *
+do_btrfs_balance_status (const char *path)
+{
+  const size_t MAX_ARGS = 64;
+  const char *argv[MAX_ARGS];
+  size_t i = 0;
+  CLEANUP_FREE char *path_buf = NULL;
+  CLEANUP_FREE char *err = NULL;
+  char *out;
+  int r;
+  guestfs_int_btrfsbalance *ret;
+  char **lines;
+  size_t nlines;
+  const char *errptr;
+  int erroffset;
+#define N_MATCH 2
+  int ovector[N_MATCH * 3];
+  pcre *re = NULL;
+
+  path_buf = sysroot_path (path);
+  if (path_buf == NULL) {
+    reply_with_perror ("malloc");
+    return NULL;
+  }
+
+  ADD_ARG (argv, i, str_btrfs);
+  ADD_ARG (argv, i, "balance");
+  ADD_ARG (argv, i, "status");
+  ADD_ARG (argv, i, path_buf);
+  ADD_ARG (argv, i, NULL);
+
+  r = commandv (&out, &err, argv);
+  if (r == -1) {
+    reply_with_error ("%s: %s", path, err);
+    return NULL;
+  }
+
+  lines = split_lines (out);
+  if (!lines)
+    return NULL;
+
+  nlines = count_strings (lines);
+
+  ret = malloc(sizeof *ret);
+  if (ret == NULL) {
+    reply_with_perror ("malloc");
+    goto error;
+  }
+  memset (ret, 0, sizeof(*ret));
+
+  /* Output of `btrfs balance status' is like:
+   *
+   * running:
+   *
+   *   Balance on '/' is running
+   *   3 out of about 8 chunks balanced (3 considered), 62% left
+   *
+   * paused:
+   *
+   *   Balance on '/' is paused
+   *   3 out of about 8 chunks balanced (3 considered), 62% left
+   *
+   * no balance running:
+   *
+   *   No Balance found on '/'
+   *
+   */
+  if (nlines < 1) {
+    reply_with_perror ("No balance status output");
+    return NULL;
+  }
+
+  if (strstr (lines[0], "No balance found on")) {
+    ret->btrfsbalance_status = strdup("none");
+    if (ret->btrfsbalance_status == NULL) {
+      reply_with_perror ("strdup");
+      return NULL;
+    }
+    return ret;
+  }
+
+  re = pcre_compile ("Balance on '.*' is (.*)", 0,
&errptr, &erroffset, NULL);
+  if (re == NULL) {
+    reply_with_error ("pcre_compile (%i): %s", erroffset, errptr);
+    goto error;
+  }
+  if (pcre_exec (re, NULL, lines[0], strlen (lines[0]), 0, 0,
+                 ovector, N_MATCH * 3) < 0) {
+    reply_with_error ("unexpected output from 'btrfs balance
status' command: %s", lines[0]);
+    goto error;
+  }
+#undef N_MATCH
+
+  if (STREQ (lines[0] + ovector[2], "running"))
+    ret->btrfsbalance_status = strdup("running");
+  else if (STREQ (lines[0] + ovector[2], "paused"))
+    ret->btrfsbalance_status = strdup("paused");
+  else {
+    reply_with_error ("unexpected output from 'btrfs balance
status' command: %s", lines[0]);
+    goto error;
+  }
+
+  if (nlines < 2) {
+    reply_with_error ("truncated output from 'btrfs balance
status' command");
+    goto error;
+  }
+
+  if (sscanf (lines[1], "%" SCNu64 " out of about %" SCNu64
+              " chunks balanced (%" SCNu64 " considered),
%" SCNu64 "%% left",
+              &ret->btrfsbalance_balanced,
&ret->btrfsbalance_total,
+              &ret->btrfsbalance_considered,
&ret->btrfsbalance_left) != 4) {
+    reply_with_perror ("sscanf");
+    goto error;
+  }
+
+  pcre_free (re);
+  return ret;
+
+error:
+  free (ret->btrfsbalance_status);
+  free (ret);
+  pcre_free (re);
+
+  return NULL;
+}
diff --git a/generator/actions.ml b/generator/actions.ml
index 6b37712..5301a29 100644
--- a/generator/actions.ml
+++ b/generator/actions.ml
@@ -12449,6 +12449,16 @@ valid GUID." };
     longdesc = "\
 Return the GUID of numbered GPT partition C<partnum>." };
 
+{ defaults with
+    name = "btrfs_balance_status";
+    style = RStruct ("status", "btrfsbalance"), [Pathname
"path"], [];
+    proc_nr = Some 448;
+    optional = Some "btrfs"; camel_name =
"BTRFSBalanceStatus";
+    test_excuse = "test disk isn't large enough that btrfs_balance
completes before we can get its status";
+    shortdesc = "show the status of a running or paused balance";
+    longdesc = "\
+Show the status of a running or paused balance on a btrfs filesystem." };
+
 ]
 
 (* Non-API meta-commands available only in guestfish.
diff --git a/generator/structs.ml b/generator/structs.ml
index 5b466a2..af42529 100644
--- a/generator/structs.ml
+++ b/generator/structs.ml
@@ -340,6 +340,18 @@ let structs = [
     ];
     s_camel_name = "BTRFSQgroup" };
 
+  (* btrfs balance status output *)
+  { defaults with
+    s_name = "btrfsbalance";
+    s_cols = [
+      "btrfsbalance_status", FString;
+      "btrfsbalance_total", FUInt64;
+      "btrfsbalance_balanced", FUInt64;
+      "btrfsbalance_considered", FUInt64;
+      "btrfsbalance_left", FUInt64;
+    ];
+    s_camel_name = "BTRFSBalance" };
+
   (* XFS info descriptor. *)
   { defaults with
     s_name = "xfsinfo";
diff --git a/gobject/Makefile.inc b/gobject/Makefile.inc
index e0c0a5f..3ce10f9 100644
--- a/gobject/Makefile.inc
+++ b/gobject/Makefile.inc
@@ -25,6 +25,7 @@ guestfs_gobject_headers= \
   include/guestfs-gobject/tristate.h \
   include/guestfs-gobject/struct-application.h \
   include/guestfs-gobject/struct-application2.h \
+  include/guestfs-gobject/struct-btrfsbalance.h \
   include/guestfs-gobject/struct-btrfsqgroup.h \
   include/guestfs-gobject/struct-btrfssubvolume.h \
   include/guestfs-gobject/struct-dirent.h \
@@ -108,6 +109,7 @@ guestfs_gobject_sources= \
   src/tristate.c \
   src/struct-application.c \
   src/struct-application2.c \
+  src/struct-btrfsbalance.c \
   src/struct-btrfsqgroup.c \
   src/struct-btrfssubvolume.c \
   src/struct-dirent.c \
diff --git a/java/Makefile.inc b/java/Makefile.inc
index 103010f..499d3de 100644
--- a/java/Makefile.inc
+++ b/java/Makefile.inc
@@ -22,6 +22,7 @@
 java_built_sources = \
 	com/redhat/et/libguestfs/Application.java \
 	com/redhat/et/libguestfs/Application2.java \
+	com/redhat/et/libguestfs/BTRFSBalance.java \
 	com/redhat/et/libguestfs/BTRFSQgroup.java \
 	com/redhat/et/libguestfs/BTRFSSubvolume.java \
 	com/redhat/et/libguestfs/Dirent.java \
diff --git a/java/com/redhat/et/libguestfs/.gitignore
b/java/com/redhat/et/libguestfs/.gitignore
index 1d4accc..b2b1b22 100644
--- a/java/com/redhat/et/libguestfs/.gitignore
+++ b/java/com/redhat/et/libguestfs/.gitignore
@@ -1,5 +1,6 @@
 Application.java
 Application2.java
+BTRFSBalance.java
 BTRFSQgroup.java
 BTRFSSubvolume.java
 Dirent.java
diff --git a/po/POTFILES b/po/POTFILES
index 6e65377..3f66c9f 100644
--- a/po/POTFILES
+++ b/po/POTFILES
@@ -230,6 +230,7 @@ gobject/src/optargs-xfs_repair.c
 gobject/src/session.c
 gobject/src/struct-application.c
 gobject/src/struct-application2.c
+gobject/src/struct-btrfsbalance.c
 gobject/src/struct-btrfsqgroup.c
 gobject/src/struct-btrfssubvolume.c
 gobject/src/struct-dirent.c
diff --git a/src/MAX_PROC_NR b/src/MAX_PROC_NR
index e9b7520..5379c47 100644
--- a/src/MAX_PROC_NR
+++ b/src/MAX_PROC_NR
@@ -1 +1 @@
-447
+448
-- 
2.1.0

From: Hu Tao <hutao@cn.fujitsu.com>

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
---
 daemon/btrfs.c                           | 142 +++++++++++++++++++++++++++++++
 generator/actions.ml                     |  16 ++++
 generator/structs.ml                     |  22 +++++
 gobject/Makefile.inc                     |   2 +
 java/Makefile.inc                        |   1 +
 java/com/redhat/et/libguestfs/.gitignore |   1 +
 po/POTFILES                              |   1 +
 src/MAX_PROC_NR                          |   2 +-
 8 files changed, 186 insertions(+), 1 deletion(-)

diff --git a/daemon/btrfs.c b/daemon/btrfs.c
index a979327..e2c3802 100644
--- a/daemon/btrfs.c
+++ b/daemon/btrfs.c
@@ -1785,3 +1785,145 @@ error:
 
   return NULL;
 }
+
+guestfs_int_btrfsscrub *
+do_btrfs_scrub_status (const char *path)
+{
+  const size_t MAX_ARGS = 64;
+  const char *argv[MAX_ARGS];
+  size_t i = 0;
+  CLEANUP_FREE char *path_buf = NULL;
+  CLEANUP_FREE char *err = NULL;
+  char *out;
+  int r;
+  guestfs_int_btrfsscrub *ret;
+  char **lines;
+
+  path_buf = sysroot_path (path);
+  if (path_buf == NULL) {
+    reply_with_perror ("malloc");
+    return NULL;
+  }
+
+  ADD_ARG (argv, i, str_btrfs);
+  ADD_ARG (argv, i, "scrub");
+  ADD_ARG (argv, i, "status");
+  ADD_ARG (argv, i, "-R");
+  ADD_ARG (argv, i, path_buf);
+  ADD_ARG (argv, i, NULL);
+
+  r = commandv (&out, &err, argv);
+  if (r == -1) {
+    reply_with_error ("%s: %s", path, err);
+    return NULL;
+  }
+
+  if (verbose)
+    fprintf (stderr, "output from 'btrfs scrub status -R %s'
is:\n%s", path, out);
+
+  lines = split_lines (out);
+  if (!lines)
+    return NULL;
+
+  if (count_strings (lines) < 2) {
+    reply_with_error ("truncated output from 'btrfs scrub status
-R' command");
+    return NULL;
+  }
+
+  ret = malloc (sizeof *ret);
+  if (ret == NULL) {
+    reply_with_perror ("malloc");
+    return NULL;
+  }
+  memset (ret, 0, sizeof(*ret));
+
+  /* Output of `btrfs scrub -R status' is like:
+   *
+   *   scrub status for 346121d1-1847-40f8-9b7b-2bf3d539c68f
+   *           scrub started at Mon Feb  2 17:39:38 2015, running for 93
seconds
+   *           data_extents_scrubbed: 136670
+   *           tree_extents_scrubbed: 30023
+   *           data_bytes_scrubbed: 4474441728
+   *           tree_bytes_scrubbed: 491896832
+   *           read_errors: 0
+   *           csum_errors: 0
+   *           verify_errors: 0
+   *           no_csum: 17760
+   *           csum_discards: 197622
+   *           super_errors: 0
+   *           malloc_errors: 0
+   *           uncorrectable_errors: 0
+   *           unverified_errors: 0
+   *           corrected_errors: 0
+   *           last_physical: 10301341696
+   *
+   * or:
+   *
+   *   scrub status for 346121d1-1847-40f8-9b7b-2bf3d539c68f
+   *           no stats available
+   */
+  for (i = 1; lines[i] != NULL; ++i) {
+    if ((i == 1) && STREQ (lines[i], "\tno stats available"))
+      return ret;
+    else if (sscanf (lines[i], "\tdata_extents_scrubbed: %" SCNu64,
+                                 &ret->btrfsscrub_data_extents_scrubbed)
== 1)
+      continue;
+    else if (sscanf (lines[i], "\ttree_extents_scrubbed: %" SCNu64,
+                                 &ret->btrfsscrub_tree_extents_scrubbed)
== 1)
+      continue;
+    else if (sscanf (lines[i], "\tdata_bytes_scrubbed: %" SCNu64,
+                                 &ret->btrfsscrub_data_bytes_scrubbed)
== 1)
+      continue;
+    else if (sscanf (lines[i], "\ttree_bytes_scrubbed: %" SCNu64,
+                                 &ret->btrfsscrub_tree_bytes_scrubbed)
== 1)
+      continue;
+    else if (sscanf (lines[i], "\tread_errors: %" SCNu64,
+                                 &ret->btrfsscrub_read_errors) == 1)
+      continue;
+    else if (sscanf (lines[i], "\tcsum_errors: %" SCNu64,
+                                 &ret->btrfsscrub_csum_errors) == 1)
+      continue;
+    else if (sscanf (lines[i], "\tverify_errors: %" SCNu64,
+                                 &ret->btrfsscrub_verify_errors) == 1)
+      continue;
+    else if (sscanf (lines[i], "\tno_csum: %" SCNu64,
+                                 &ret->btrfsscrub_no_csum) == 1)
+      continue;
+    else if (sscanf (lines[i], "\tcsum_discards: %" SCNu64,
+                                  &ret->btrfsscrub_csum_discards) == 1)
+      continue;
+    else if (sscanf (lines[i], "\tsuper_errors: %" SCNu64,
+                                  &ret->btrfsscrub_super_errors) == 1)
+      continue;
+    else if (sscanf (lines[i], "\tmalloc_errors: %" SCNu64,
+                                  &ret->btrfsscrub_malloc_errors) == 1)
+      continue;
+    else if (sscanf (lines[i], "\tuncorrectable_errors: %" SCNu64,
+                                  &ret->btrfsscrub_uncorrectable_errors)
== 1)
+      continue;
+    else if (sscanf (lines[i], "\tunverified_errors: %" SCNu64,
+                                  &ret->btrfsscrub_unverified_errors) ==
1)
+      continue;
+    else if (sscanf (lines[i], "\tcorrected_errors: %" SCNu64,
+                                  &ret->btrfsscrub_corrected_errors) ==
1)
+      continue;
+    else if (sscanf (lines[i], "\tlast_physical: %" SCNu64,
+                                  &ret->btrfsscrub_last_physical) == 1)
+      continue;
+    else
+      goto error;
+  }
+
+  if (i < 17) {
+    reply_with_error ("truncated output from 'btrfs scrub status
-R' command");
+    free (ret);
+    return NULL;
+  }
+
+  return ret;
+
+error:
+  reply_with_error ("%s: could not parse btrfs scrub status.",
lines[i]);
+  free (ret);
+  return NULL;
+}
diff --git a/generator/actions.ml b/generator/actions.ml
index 5301a29..f82ac32 100644
--- a/generator/actions.ml
+++ b/generator/actions.ml
@@ -12459,6 +12459,22 @@ Return the GUID of numbered GPT partition
C<partnum>." };
     longdesc = "\
 Show the status of a running or paused balance on a btrfs filesystem." };
 
+  { defaults with
+    name = "btrfs_scrub_status";
+    style = RStruct ("status", "btrfsscrub"), [Pathname
"path"], [];
+    proc_nr = Some 449;
+    optional = Some "btrfs"; camel_name =
"BTRFSScrubStatus";
+    tests = [
+      InitPartition, Always, TestRun (
+        [["mkfs_btrfs"; "/dev/sda1"; "";
""; "NOARG"; ""; "NOARG";
"NOARG"; ""; ""];
+         ["mount"; "/dev/sda1"; "/"];
+         ["btrfs_scrub_start"; "/"];
+         ["btrfs_scrub_status"; "/"]]), [];
+    ];
+    shortdesc = "show status of running or finished scrub";
+    longdesc = "\
+Show status of running or finished scrub on a btrfs filesystem." };
+
 ]
 
 (* Non-API meta-commands available only in guestfish.
diff --git a/generator/structs.ml b/generator/structs.ml
index af42529..ea110a1 100644
--- a/generator/structs.ml
+++ b/generator/structs.ml
@@ -352,6 +352,28 @@ let structs = [
     ];
     s_camel_name = "BTRFSBalance" };
 
+  (* btrfs scrub status output *)
+  { defaults with
+    s_name = "btrfsscrub";
+    s_cols = [
+      "btrfsscrub_data_extents_scrubbed", FUInt64;
+      "btrfsscrub_tree_extents_scrubbed", FUInt64;
+      "btrfsscrub_data_bytes_scrubbed", FUInt64;
+      "btrfsscrub_tree_bytes_scrubbed", FUInt64;
+      "btrfsscrub_read_errors", FUInt64;
+      "btrfsscrub_csum_errors", FUInt64;
+      "btrfsscrub_verify_errors", FUInt64;
+      "btrfsscrub_no_csum", FUInt64;
+      "btrfsscrub_csum_discards", FUInt64;
+      "btrfsscrub_super_errors", FUInt64;
+      "btrfsscrub_malloc_errors", FUInt64;
+      "btrfsscrub_uncorrectable_errors", FUInt64;
+      "btrfsscrub_unverified_errors", FUInt64;
+      "btrfsscrub_corrected_errors", FUInt64;
+      "btrfsscrub_last_physical", FUInt64;
+    ];
+    s_camel_name = "BTRFSScrub" };
+
   (* XFS info descriptor. *)
   { defaults with
     s_name = "xfsinfo";
diff --git a/gobject/Makefile.inc b/gobject/Makefile.inc
index 3ce10f9..6bbd72c 100644
--- a/gobject/Makefile.inc
+++ b/gobject/Makefile.inc
@@ -27,6 +27,7 @@ guestfs_gobject_headers= \
   include/guestfs-gobject/struct-application2.h \
   include/guestfs-gobject/struct-btrfsbalance.h \
   include/guestfs-gobject/struct-btrfsqgroup.h \
+  include/guestfs-gobject/struct-btrfsscrub.h \
   include/guestfs-gobject/struct-btrfssubvolume.h \
   include/guestfs-gobject/struct-dirent.h \
   include/guestfs-gobject/struct-hivex_node.h \
@@ -111,6 +112,7 @@ guestfs_gobject_sources= \
   src/struct-application2.c \
   src/struct-btrfsbalance.c \
   src/struct-btrfsqgroup.c \
+  src/struct-btrfsscrub.c \
   src/struct-btrfssubvolume.c \
   src/struct-dirent.c \
   src/struct-hivex_node.c \
diff --git a/java/Makefile.inc b/java/Makefile.inc
index 499d3de..477842a 100644
--- a/java/Makefile.inc
+++ b/java/Makefile.inc
@@ -24,6 +24,7 @@ java_built_sources = \
 	com/redhat/et/libguestfs/Application2.java \
 	com/redhat/et/libguestfs/BTRFSBalance.java \
 	com/redhat/et/libguestfs/BTRFSQgroup.java \
+	com/redhat/et/libguestfs/BTRFSScrub.java \
 	com/redhat/et/libguestfs/BTRFSSubvolume.java \
 	com/redhat/et/libguestfs/Dirent.java \
 	com/redhat/et/libguestfs/HivexNode.java \
diff --git a/java/com/redhat/et/libguestfs/.gitignore
b/java/com/redhat/et/libguestfs/.gitignore
index b2b1b22..8389269 100644
--- a/java/com/redhat/et/libguestfs/.gitignore
+++ b/java/com/redhat/et/libguestfs/.gitignore
@@ -2,6 +2,7 @@ Application.java
 Application2.java
 BTRFSBalance.java
 BTRFSQgroup.java
+BTRFSScrub.java
 BTRFSSubvolume.java
 Dirent.java
 HivexNode.java
diff --git a/po/POTFILES b/po/POTFILES
index 3f66c9f..f1c42fe 100644
--- a/po/POTFILES
+++ b/po/POTFILES
@@ -232,6 +232,7 @@ gobject/src/struct-application.c
 gobject/src/struct-application2.c
 gobject/src/struct-btrfsbalance.c
 gobject/src/struct-btrfsqgroup.c
+gobject/src/struct-btrfsscrub.c
 gobject/src/struct-btrfssubvolume.c
 gobject/src/struct-dirent.c
 gobject/src/struct-hivex_node.c
diff --git a/src/MAX_PROC_NR b/src/MAX_PROC_NR
index 5379c47..2b20fd0 100644
--- a/src/MAX_PROC_NR
+++ b/src/MAX_PROC_NR
@@ -1 +1 @@
-448
+449
-- 
2.1.0

On Fri, Feb 13, 2015 at 06:06:54PM +0800, Chen Hanxiao
wrote:
> From: Hu Tao <hutao@cn.fujitsu.com>
> 
> Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
> Signed-off-by: Chen Hanxiao <chenhanxiao@cn.fujitsu.com>
> ---
>  daemon/btrfs.c                           | 126
+++++++++++++++++++++++++++++++
>  generator/actions.ml                     |  10 +++
>  generator/structs.ml                     |  12 +++
>  gobject/Makefile.inc                     |   2 +
>  java/Makefile.inc                        |   1 +
>  java/com/redhat/et/libguestfs/.gitignore |   1 +
>  po/POTFILES                              |   1 +
>  src/MAX_PROC_NR                          |   2 +-
>  8 files changed, 154 insertions(+), 1 deletion(-)
> 
> diff --git a/daemon/btrfs.c b/daemon/btrfs.c
> index 5cab52a..a979327 100644
> --- a/daemon/btrfs.c
> +++ b/daemon/btrfs.c
> @@ -1659,3 +1659,129 @@ do_btrfs_rescue_super_recover (const char *device)
>  
>    return 0;
>  }
> +
> +guestfs_int_btrfsbalance *
> +do_btrfs_balance_status (const char *path)
> +{
> +  const size_t MAX_ARGS = 64;
> +  const char *argv[MAX_ARGS];
> +  size_t i = 0;
> +  CLEANUP_FREE char *path_buf = NULL;
> +  CLEANUP_FREE char *err = NULL;
> +  char *out;
> +  int r;
> +  guestfs_int_btrfsbalance *ret;
> +  char **lines;
> +  size_t nlines;
> +  const char *errptr;
> +  int erroffset;
> +#define N_MATCH 2
> +  int ovector[N_MATCH * 3];
> +  pcre *re = NULL;
> +
> +  path_buf = sysroot_path (path);
> +  if (path_buf == NULL) {
> +    reply_with_perror ("malloc");
> +    return NULL;
> +  }
> +
> +  ADD_ARG (argv, i, str_btrfs);
> +  ADD_ARG (argv, i, "balance");
> +  ADD_ARG (argv, i, "status");
> +  ADD_ARG (argv, i, path_buf);
> +  ADD_ARG (argv, i, NULL);
> +
> +  r = commandv (&out, &err, argv);
> +  if (r == -1) {
> +    reply_with_error ("%s: %s", path, err);
> +    return NULL;
> +  }
> +
> +  lines = split_lines (out);
> +  if (!lines)
> +    return NULL;
> +
> +  nlines = count_strings (lines);
> +
> +  ret = malloc(sizeof *ret);
> +  if (ret == NULL) {
> +    reply_with_perror ("malloc");
> +    goto error;
> +  }
> +  memset (ret, 0, sizeof(*ret));
> +
> +  /* Output of `btrfs balance status' is like:
> +   *
> +   * running:
> +   *
> +   *   Balance on '/' is running
> +   *   3 out of about 8 chunks balanced (3 considered), 62% left
> +   *
> +   * paused:
> +   *
> +   *   Balance on '/' is paused
> +   *   3 out of about 8 chunks balanced (3 considered), 62% left
> +   *
> +   * no balance running:
> +   *
> +   *   No Balance found on '/'
> +   *
> +   */
> +  if (nlines < 1) {
> +    reply_with_perror ("No balance status output");
reply_with_perror uses errno implicitly, but errno would not be set to
anything interesting here.

I will push these patches, with a few fixes.

Thanks,

Rich.
> +    return NULL;
> +  }
> +
> +  if (strstr (lines[0], "No balance found on")) {
> +    ret->btrfsbalance_status = strdup("none");
> +    if (ret->btrfsbalance_status == NULL) {
> +      reply_with_perror ("strdup");
> +      return NULL;
> +    }
> +    return ret;
> +  }
> +
> +  re = pcre_compile ("Balance on '.*' is (.*)", 0,
&errptr, &erroffset, NULL);
> +  if (re == NULL) {
> +    reply_with_error ("pcre_compile (%i): %s", erroffset,
errptr);
> +    goto error;
> +  }
> +  if (pcre_exec (re, NULL, lines[0], strlen (lines[0]), 0, 0,
> +                 ovector, N_MATCH * 3) < 0) {
> +    reply_with_error ("unexpected output from 'btrfs balance
status' command: %s", lines[0]);
> +    goto error;
> +  }
> +#undef N_MATCH
> +
> +  if (STREQ (lines[0] + ovector[2], "running"))
> +    ret->btrfsbalance_status = strdup("running");
> +  else if (STREQ (lines[0] + ovector[2], "paused"))
> +    ret->btrfsbalance_status = strdup("paused");
> +  else {
> +    reply_with_error ("unexpected output from 'btrfs balance
status' command: %s", lines[0]);
> +    goto error;
> +  }
> +
> +  if (nlines < 2) {
> +    reply_with_error ("truncated output from 'btrfs balance
status' command");
> +    goto error;
> +  }
> +
> +  if (sscanf (lines[1], "%" SCNu64 " out of about %"
SCNu64
> +              " chunks balanced (%" SCNu64 " considered),
%" SCNu64 "%% left",
> +              &ret->btrfsbalance_balanced,
&ret->btrfsbalance_total,
> +              &ret->btrfsbalance_considered,
&ret->btrfsbalance_left) != 4) {
> +    reply_with_perror ("sscanf");
> +    goto error;
> +  }
> +
> +  pcre_free (re);
> +  return ret;
> +
> +error:
> +  free (ret->btrfsbalance_status);
> +  free (ret);
> +  pcre_free (re);
> +
> +  return NULL;
> +}
> diff --git a/generator/actions.ml b/generator/actions.ml
> index 6b37712..5301a29 100644
> --- a/generator/actions.ml
> +++ b/generator/actions.ml
> @@ -12449,6 +12449,16 @@ valid GUID." };
>      longdesc = "\
>  Return the GUID of numbered GPT partition C<partnum>." };
>  
> +{ defaults with
> +    name = "btrfs_balance_status";
> +    style = RStruct ("status", "btrfsbalance"),
[Pathname "path"], [];
> +    proc_nr = Some 448;
> +    optional = Some "btrfs"; camel_name =
"BTRFSBalanceStatus";
> +    test_excuse = "test disk isn't large enough that
btrfs_balance completes before we can get its status";
> +    shortdesc = "show the status of a running or paused
balance";
> +    longdesc = "\
> +Show the status of a running or paused balance on a btrfs
filesystem." };
> +
>  ]
>  
>  (* Non-API meta-commands available only in guestfish.
> diff --git a/generator/structs.ml b/generator/structs.ml
> index 5b466a2..af42529 100644
> --- a/generator/structs.ml
> +++ b/generator/structs.ml
> @@ -340,6 +340,18 @@ let structs = [
>      ];
>      s_camel_name = "BTRFSQgroup" };
>  
> +  (* btrfs balance status output *)
> +  { defaults with
> +    s_name = "btrfsbalance";
> +    s_cols = [
> +      "btrfsbalance_status", FString;
> +      "btrfsbalance_total", FUInt64;
> +      "btrfsbalance_balanced", FUInt64;
> +      "btrfsbalance_considered", FUInt64;
> +      "btrfsbalance_left", FUInt64;
> +    ];
> +    s_camel_name = "BTRFSBalance" };
> +
>    (* XFS info descriptor. *)
>    { defaults with
>      s_name = "xfsinfo";
> diff --git a/gobject/Makefile.inc b/gobject/Makefile.inc
> index e0c0a5f..3ce10f9 100644
> --- a/gobject/Makefile.inc
> +++ b/gobject/Makefile.inc
> @@ -25,6 +25,7 @@ guestfs_gobject_headers= \
>    include/guestfs-gobject/tristate.h \
>    include/guestfs-gobject/struct-application.h \
>    include/guestfs-gobject/struct-application2.h \
> +  include/guestfs-gobject/struct-btrfsbalance.h \
>    include/guestfs-gobject/struct-btrfsqgroup.h \
>    include/guestfs-gobject/struct-btrfssubvolume.h \
>    include/guestfs-gobject/struct-dirent.h \
> @@ -108,6 +109,7 @@ guestfs_gobject_sources= \
>    src/tristate.c \
>    src/struct-application.c \
>    src/struct-application2.c \
> +  src/struct-btrfsbalance.c \
>    src/struct-btrfsqgroup.c \
>    src/struct-btrfssubvolume.c \
>    src/struct-dirent.c \
> diff --git a/java/Makefile.inc b/java/Makefile.inc
> index 103010f..499d3de 100644
> --- a/java/Makefile.inc
> +++ b/java/Makefile.inc
> @@ -22,6 +22,7 @@
>  java_built_sources = \
>  	com/redhat/et/libguestfs/Application.java \
>  	com/redhat/et/libguestfs/Application2.java \
> +	com/redhat/et/libguestfs/BTRFSBalance.java \
>  	com/redhat/et/libguestfs/BTRFSQgroup.java \
>  	com/redhat/et/libguestfs/BTRFSSubvolume.java \
>  	com/redhat/et/libguestfs/Dirent.java \
> diff --git a/java/com/redhat/et/libguestfs/.gitignore
b/java/com/redhat/et/libguestfs/.gitignore
> index 1d4accc..b2b1b22 100644
> --- a/java/com/redhat/et/libguestfs/.gitignore
> +++ b/java/com/redhat/et/libguestfs/.gitignore
> @@ -1,5 +1,6 @@
>  Application.java
>  Application2.java
> +BTRFSBalance.java
>  BTRFSQgroup.java
>  BTRFSSubvolume.java
>  Dirent.java
> diff --git a/po/POTFILES b/po/POTFILES
> index 6e65377..3f66c9f 100644
> --- a/po/POTFILES
> +++ b/po/POTFILES
> @@ -230,6 +230,7 @@ gobject/src/optargs-xfs_repair.c
>  gobject/src/session.c
>  gobject/src/struct-application.c
>  gobject/src/struct-application2.c
> +gobject/src/struct-btrfsbalance.c
>  gobject/src/struct-btrfsqgroup.c
>  gobject/src/struct-btrfssubvolume.c
>  gobject/src/struct-dirent.c
> diff --git a/src/MAX_PROC_NR b/src/MAX_PROC_NR
> index e9b7520..5379c47 100644
> --- a/src/MAX_PROC_NR
> +++ b/src/MAX_PROC_NR
> @@ -1 +1 @@
> -447
> +448
> -- 
> 2.1.0
> 
> _______________________________________________
> Libguestfs mailing list
> Libguestfs@redhat.com
> https://www.redhat.com/mailman/listinfo/libguestfs
-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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