Libguestfs - Feb 2015 - [PATCH 1/2] New API: btrfs_balance_status

Signed-off-by: Hu Tao <hutao at cn.fujitsu.com>
---

These two patches are refactored to parse the output info structures.

 daemon/btrfs.c                           | 109 +++++++++++++++++++++++++++++++
 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, 137 insertions(+), 1 deletion(-)

diff --git a/daemon/btrfs.c b/daemon/btrfs.c
index 796eaff..bb82f32 100644
--- a/daemon/btrfs.c
+++ b/daemon/btrfs.c
@@ -1659,3 +1659,112 @@ 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;
+  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;
+
+  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 (strstr (lines[0], "No balance found on")) {
+    ret->btrfsbalance_status = strdup("none");
+    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 (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 c0beaae..f943ecb 100644
--- a/generator/actions.ml
+++ b/generator/actions.ml
@@ -12385,6 +12385,16 @@ Recover the chunk tree of btrfs filesystem by scannning
the devices one by one."
     longdesc = "\
 Recover bad superblocks from good copies." };
 
+{ defaults with
+    name = "btrfs_balance_status";
+    style = RStruct ("status", "btrfsbalance"), [Pathname
"path"], [];
+    proc_nr = Some 446;
+    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 4194e5f..9330256 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 e5a135a..0187835 100644
--- a/src/MAX_PROC_NR
+++ b/src/MAX_PROC_NR
@@ -1 +1 @@
-445
+446
-- 
2.1.0

Signed-off-by: Hu Tao <hutao at 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 bb82f32..0f49fb5 100644
--- a/daemon/btrfs.c
+++ b/daemon/btrfs.c
@@ -1768,3 +1768,145 @@ 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;
+  char *line;
+
+  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;
+  }
+
+  lines = split_lines (out);
+  if (!lines)
+    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:
+   *
+   *   strub 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:
+   *
+   *   strub status for 346121d1-1847-40f8-9b7b-2bf3d539c68f
+   *           no stats available
+   */
+  line = lines[1];
+  if (STREQ (line, "\tno stats available"))
+    return ret;
+
+  line = lines[2];
+  if (sscanf (line, "\tdata_extents_scrubbed: %" SCNu64,
+              &ret->btrfsscrub_data_extents_scrubbed) != 1)
+    goto error;
+  line = lines[3];
+  if (sscanf (line, "\ttree_extents_scrubbed: %" SCNu64,
+              &ret->btrfsscrub_tree_extents_scrubbed) != 1)
+    goto error;
+  line = lines[4];
+  if (sscanf (line, "\tdata_bytes_scrubbed: %" SCNu64,
+              &ret->btrfsscrub_data_bytes_scrubbed) != 1)
+    goto error;
+  line = lines[5];
+  if (sscanf (line, "\ttree_bytes_scrubbed: %" SCNu64,
+              &ret->btrfsscrub_tree_bytes_scrubbed) != 1)
+    goto error;
+  line = lines[6];
+  if (sscanf (line, "\tread_errors: %" SCNu64,
+              &ret->btrfsscrub_read_errors) != 1)
+    goto error;
+  line = lines[7];
+  if (sscanf (line, "\tcsum_errors: %" SCNu64,
+              &ret->btrfsscrub_csum_errors) != 1)
+    goto error;
+  line = lines[8];
+  if (sscanf (line, "\tverify_errors: %" SCNu64,
+              &ret->btrfsscrub_verify_errors) != 1)
+    goto error;
+  line = lines[9];
+  if (sscanf (line, "\tno_csum: %" SCNu64,
+              &ret->btrfsscrub_no_csum) != 1)
+    goto error;
+  line = lines[10];
+  if (sscanf (line, "\tcsum_discards: %" SCNu64,
+              &ret->btrfsscrub_csum_discards) != 1)
+    goto error;
+  line = lines[11];
+  if (sscanf (line, "\tsuper_errors: %" SCNu64,
+              &ret->btrfsscrub_super_errors) != 1)
+    goto error;
+  line = lines[12];
+  if (sscanf (line, "\tmalloc_errors: %" SCNu64,
+              &ret->btrfsscrub_malloc_errors) != 1)
+    goto error;
+  line = lines[13];
+  if (sscanf (line, "\tuncorrectable_errors: %" SCNu64,
+              &ret->btrfsscrub_uncorrectable_errors) != 1)
+    goto error;
+  line = lines[14];
+  if (sscanf (line, "\tunverified_errors: %" SCNu64,
+              &ret->btrfsscrub_unverified_errors) != 1)
+    goto error;
+  line = lines[15];
+  if (sscanf (line, "\tcorrected_errors: %" SCNu64,
+              &ret->btrfsscrub_corrected_errors) != 1)
+    goto error;
+  line = lines[16];
+  if (sscanf (line, "\tlast_physical: %" SCNu64,
+              &ret->btrfsscrub_last_physical) != 1)
+    goto error;
+
+  return ret;
+
+error:
+  reply_with_error ("%s: could not parse btrfs scrub status.", line);
+  free (ret);
+  return NULL;
+}
diff --git a/generator/actions.ml b/generator/actions.ml
index f943ecb..a2d43e4 100644
--- a/generator/actions.ml
+++ b/generator/actions.ml
@@ -12395,6 +12395,22 @@ Recover bad superblocks from good copies." };
     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 447;
+    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 9330256..5d089ac 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 0187835..e9b7520 100644
--- a/src/MAX_PROC_NR
+++ b/src/MAX_PROC_NR
@@ -1 +1 @@
-446
+447
-- 
2.1.0

On Mon, Feb 02, 2015 at 02:11:31PM +0800, Hu Tao wrote:
> Signed-off-by: Hu Tao <hutao at cn.fujitsu.com>
I'm just running some manual tests on this patch series, but it looks
good and if I find no compile/test problems then I'll commit both.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-df lists disk usage of guests without needing to install any
software inside the virtual machine.  Supports Linux and Windows.
http://people.redhat.com/~rjones/virt-df/

On Mon, Feb 02, 2015 at 02:11:31PM +0800, Hu Tao wrote:
[..]

So in fact there are a few problems.  I couldn't get btrfs balance to
actually do anything at all (perhaps it doesn't work on empty
filesystems), so this come only from code inspection.
> +  lines = split_lines (out);
> +  if (!lines)
> +    return NULL;
> +
> +  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 (strstr (lines[0], "No balance found on")) {
In case the output of the btrfs command changes in future, you need to
check that the length of the lines[] array is >= 1 here, and >= 2
below.  Otherwise this code will segfault.
> +    ret->btrfsbalance_status = strdup("none");
Where you call strdup, you have to check that the return value is not
NULL, and if it is call reply_with_perror ("strdup").
> +    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 (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;
Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
bindings from many languages.  http://libguestfs.org

On Mon, Feb 02, 2015 at 02:11:32PM +0800, Hu Tao wrote:
> Signed-off-by: Hu Tao <hutao@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 bb82f32..0f49fb5 100644
> --- a/daemon/btrfs.c
> +++ b/daemon/btrfs.c
> @@ -1768,3 +1768,145 @@ 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;
> +  char *line;
> +
> +  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;
> +  }
> +
> +  lines = split_lines (out);
> +  if (!lines)
> +    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:
> +   *
> +   *   strub 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:
> +   *
> +   *   strub status for 346121d1-1847-40f8-9b7b-2bf3d539c68f
> +   *           no stats available
> +   */
> +  line = lines[1];
Again, I doubt that the output of btrfs scrub -R status will remain
the same forever.  You need to at least check that lines[] is
sufficiently long to avoid a possible segfault, and it's probably
better to use a loop here.  Compare the function xfs.c:parse_xfs_info()

Rich.
> +  if (STREQ (line, "\tno stats available"))
> +    return ret;
> +
> +  line = lines[2];
> +  if (sscanf (line, "\tdata_extents_scrubbed: %" SCNu64,
> +              &ret->btrfsscrub_data_extents_scrubbed) != 1)
> +    goto error;
> +  line = lines[3];
> +  if (sscanf (line, "\ttree_extents_scrubbed: %" SCNu64,
> +              &ret->btrfsscrub_tree_extents_scrubbed) != 1)
> +    goto error;
> +  line = lines[4];
> +  if (sscanf (line, "\tdata_bytes_scrubbed: %" SCNu64,
> +              &ret->btrfsscrub_data_bytes_scrubbed) != 1)
> +    goto error;
> +  line = lines[5];
> +  if (sscanf (line, "\ttree_bytes_scrubbed: %" SCNu64,
> +              &ret->btrfsscrub_tree_bytes_scrubbed) != 1)
> +    goto error;
> +  line = lines[6];
> +  if (sscanf (line, "\tread_errors: %" SCNu64,
> +              &ret->btrfsscrub_read_errors) != 1)
> +    goto error;
> +  line = lines[7];
> +  if (sscanf (line, "\tcsum_errors: %" SCNu64,
> +              &ret->btrfsscrub_csum_errors) != 1)
> +    goto error;
> +  line = lines[8];
> +  if (sscanf (line, "\tverify_errors: %" SCNu64,
> +              &ret->btrfsscrub_verify_errors) != 1)
> +    goto error;
> +  line = lines[9];
> +  if (sscanf (line, "\tno_csum: %" SCNu64,
> +              &ret->btrfsscrub_no_csum) != 1)
> +    goto error;
> +  line = lines[10];
> +  if (sscanf (line, "\tcsum_discards: %" SCNu64,
> +              &ret->btrfsscrub_csum_discards) != 1)
> +    goto error;
> +  line = lines[11];
> +  if (sscanf (line, "\tsuper_errors: %" SCNu64,
> +              &ret->btrfsscrub_super_errors) != 1)
> +    goto error;
> +  line = lines[12];
> +  if (sscanf (line, "\tmalloc_errors: %" SCNu64,
> +              &ret->btrfsscrub_malloc_errors) != 1)
> +    goto error;
> +  line = lines[13];
> +  if (sscanf (line, "\tuncorrectable_errors: %" SCNu64,
> +              &ret->btrfsscrub_uncorrectable_errors) != 1)
> +    goto error;
> +  line = lines[14];
> +  if (sscanf (line, "\tunverified_errors: %" SCNu64,
> +              &ret->btrfsscrub_unverified_errors) != 1)
> +    goto error;
> +  line = lines[15];
> +  if (sscanf (line, "\tcorrected_errors: %" SCNu64,
> +              &ret->btrfsscrub_corrected_errors) != 1)
> +    goto error;
> +  line = lines[16];
> +  if (sscanf (line, "\tlast_physical: %" SCNu64,
> +              &ret->btrfsscrub_last_physical) != 1)
> +    goto error;
> +
> +  return ret;
> +
> +error:
> +  reply_with_error ("%s: could not parse btrfs scrub status.",
line);
> +  free (ret);
> +  return NULL;
> +}
> diff --git a/generator/actions.ml b/generator/actions.ml
> index f943ecb..a2d43e4 100644
> --- a/generator/actions.ml
> +++ b/generator/actions.ml
> @@ -12395,6 +12395,22 @@ Recover bad superblocks from good copies." };
>      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 447;
> +    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 9330256..5d089ac 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 0187835..e9b7520 100644
> --- a/src/MAX_PROC_NR
> +++ b/src/MAX_PROC_NR
> @@ -1 +1 @@
> -446
> +447
> -- 
> 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
virt-top is 'top' for virtual machines.  Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://people.redhat.com/~rjones/virt-top

On Mon, Feb 02, 2015 at 01:29:35PM +0000, Richard W.M. Jones
wrote:
> On Mon, Feb 02, 2015 at 02:11:31PM +0800, Hu Tao wrote:
> [..]
> 
> So in fact there are a few problems.  I couldn't get btrfs balance to
> actually do anything at all (perhaps it doesn't work on empty
> filesystems), so this come only from code inspection.
Thou I can get btrfs-balance run, but it seems like a sync operation,
i.e. when it returns the balance operation has already completed.

I tested btrfs-balance-status by faking the "out", both normal ones
and
malformed ones.
> 
> > +  lines = split_lines (out);
> > +  if (!lines)
> > +    return NULL;
> > +
> > +  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 (strstr (lines[0], "No balance found on")) {
> 
> In case the output of the btrfs command changes in future, you need to
> check that the length of the lines[] array is >= 1 here, and >= 2
> below.  Otherwise this code will segfault.
Fixed. Also fixed in patch 2.
> 
> > +    ret->btrfsbalance_status = strdup("none");
> 
> Where you call strdup, you have to check that the return value is not
> NULL, and if it is call reply_with_perror ("strdup").
Fixed.

Thank you for reviewing!

Regards,
Hu