[Libguestfs] [PATCH v2 2/2] New API: btrfs_device_stats

[Cao jin]

Signed-off-by: Cao jin <caoj.fnst at cn.fujitsu.com>
---
 daemon/btrfs.c       | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 generator/actions.ml | 10 ++++++++
 2 files changed, 74 insertions(+)

diff --git a/daemon/btrfs.c b/daemon/btrfs.c
index caa28ca..e9b65c3 100644
--- a/daemon/btrfs.c
+++ b/daemon/btrfs.c
@@ -2083,3 +2083,67 @@ do_btrfs_image (char *const *sources, const char *image,
   return 0;
 }
 
+char **
+do_btrfs_device_stats (const char *path)
+{
+  const size_t MAX_ARGS = 64;
+  const char *argv[MAX_ARGS];
+  size_t i = 0;
+  CLEANUP_FREE char *buf = NULL;
+  CLEANUP_FREE char *err = NULL;
+  CLEANUP_FREE char *out = NULL;
+  char *p, *key = NULL, *value = NULL;
+  DECLARE_STRINGSBUF (ret);
+  int r;
+  int is_dev;
+
+  is_dev = STREQLEN (path, "/dev/", 5);
+  buf = is_dev ? strdup (path) : sysroot_path (path);
+  if (buf == NULL) {
+    reply_with_perror ("malloc");
+    return NULL;
+  }
+
+  ADD_ARG (argv, i, str_btrfs);
+  ADD_ARG (argv, i, "device");
+  ADD_ARG (argv, i, "stats");
+  ADD_ARG (argv, i, buf);
+  ADD_ARG (argv, i, NULL);
+
+  r = commandv (&out, &err, argv);
+  if (r == -1) {
+    reply_with_error ("%s: %s", path, err);
+    return NULL;
+  }
+
+  /* Output pattern is:
+   *   [/dev/sda].write_io_errs   0
+   *   [/dev/sda].read_io_errs    0
+   *   [/dev/sda].flush_io_errs   0
+   *   [/dev/sda].corruption_errs 0
+   *   [/dev/sda].generation_errs 0
+   *   [/dev/sdb].write_io_errs   0
+   *   [/dev/sdb].read_io_errs    0
+   *   [/dev/sdb].flush_io_errs   0
+   *   [/dev/sdb].corruption_errs 0
+   *   [/dev/sdb].generation_errs 0
+   *   ...
+   */
+
+  /* Read the lines and split into "key: value". */
+  p = analyze_line(out, &key, &value, ' ');
+  while (key) {
+    if (add_string (&ret, key) == -1)
+      goto error;
+
+    if (add_string (&ret, value) == -1)
+      goto error;
+
+    p = analyze_line(p, &key, &value, ' ');
+  }
+
+  if (end_stringsbuf (&ret) == -1)
+    goto error;
+
+  return ret.argv;
+
+error:
+  if (ret.argv != NULL)
+    free_stringslen (ret.argv, ret.size);
+
+  return NULL;
+}
diff --git a/generator/actions.ml b/generator/actions.ml
index d5e5ccf..8d279fd 100644
--- a/generator/actions.ml
+++ b/generator/actions.ml
@@ -12593,6 +12593,16 @@ numbered C<partnum> on device C<device>.
 
 It returns C<primary>, C<logical>, or C<extended>." };
 
+  { defaults with
+    name = "btrfs_device_stats"; added = (1, 29, 47);
+    style = RHashtable "devicestats", [Dev_or_Path "path"], [];
+    proc_nr = Some 456;
+    optional = Some "btrfs"; camel_name = "BTRFSDeviceStats";
+    shortdesc = "read and print the device IO stats for mounted btrfs device";
+    longdesc = "\
+Read and print the device IO stats for all mounted devices of the filesystem
+identified by C<path>, or for a single device identified by C<path>." };
+
 ]
 
 (* Non-API meta-commands available only in guestfish.
-- 
2.1.0