[Libguestfs] [PATCH] New API: btrfs_device_stats

Cao jin caoj.fnst at cn.fujitsu.com
Tue Jun 16 09:10:09 UTC 2015


Also modified a public function: analyze_line, make it more flexible

Signed-off-by: Cao jin <caoj.fnst at cn.fujitsu.com>
---
 daemon/btrfs.c       | 83 +++++++++++++++++++++++++++++++++++++++++++++++-----
 generator/actions.ml | 12 ++++++++
 2 files changed, 88 insertions(+), 7 deletions(-)

diff --git a/daemon/btrfs.c b/daemon/btrfs.c
index 39392f7..f913f66 100644
--- a/daemon/btrfs.c
+++ b/daemon/btrfs.c
@@ -853,11 +853,11 @@ do_btrfs_fsck (const char *device, int64_t superblock, int repair)
  * returns the next position following \n.
  */
 static char *
-analyze_line (char *line, char **key, char **value)
+analyze_line (char *line, char **key, char **value, char delim)
 {
   char *p = line;
   char *next = NULL;
-  char delimiter = ':';
+  char delimiter = delim;
   char *del_pos = NULL;
 
   if (!line || *line == '\0') {
@@ -964,7 +964,7 @@ do_btrfs_subvolume_show (const char *subvolume)
    *                                 snapshots/test3
    *
    */
-  p = analyze_line(out, &key, &value);
+  p = analyze_line(out, &key, &value, ':');
   if (!p) {
     reply_with_error ("truncated output: %s", out);
     return NULL;
@@ -984,7 +984,7 @@ do_btrfs_subvolume_show (const char *subvolume)
   }
 
   /* Read the lines and split into "key: value". */
-  p = analyze_line(p, &key, &value);
+  p = analyze_line(p, &key, &value, ':');
   while (key) {
     /* snapshot is special, see the output above */
     if (STREQLEN (key, "Snapshot(s)", sizeof ("Snapshot(s)") - 1)) {
@@ -994,7 +994,7 @@ do_btrfs_subvolume_show (const char *subvolume)
       if (add_string (&ret, key) == -1)
         return NULL;
 
-      p = analyze_line(p, &key, &value);
+      p = analyze_line(p, &key, &value, ':');
 
       while (key && !value) {
           ss = realloc (ss, ss_len + strlen (key) + 1);
@@ -1008,7 +1008,7 @@ do_btrfs_subvolume_show (const char *subvolume)
           ss_len += strlen (key);
           ss[ss_len] = '\0';
 
-          p = analyze_line(p, &key, &value);
+          p = analyze_line(p, &key, &value, ':');
       }
 
       if (ss) {
@@ -1031,7 +1031,7 @@ do_btrfs_subvolume_show (const char *subvolume)
           return NULL;
       }
 
-      p = analyze_line(p, &key, &value);
+      p = analyze_line(p, &key, &value, ':');
     }
   }
 
@@ -2083,3 +2083,72 @@ do_btrfs_image (char *const *sources, const char *image,
 
   return 0;
 }
+
+char **
+do_btrfs_device_stats (const char *path, int zero)
+{
+  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);
+
+  if ((optargs_bitmask & GUESTFS_BTRFS_DEVICE_STATS_ZERO_BITMASK) && zero) {
+    ADD_ARG (argv, i, "-z");
+  }
+
+  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
+   *
+  */
+
+  /* Read the lines and split into "key: value". */
+  p = analyze_line(out, &key, &value, ' ');
+  while(key)
+  {
+    if (add_string (&ret, key) == -1)
+      return NULL;
+
+    if (add_string (&ret, value) == -1)
+      return NULL;
+
+    p = analyze_line(p, &key, &value, ' ');
+  }
+
+  if (end_stringsbuf (&ret) == -1)
+    return NULL;
+
+  return ret.argv;
+}
+
diff --git a/generator/actions.ml b/generator/actions.ml
index d5e5ccf..dfb42b5 100644
--- a/generator/actions.ml
+++ b/generator/actions.ml
@@ -12593,6 +12593,18 @@ 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, 46);
+    style = RHashtable "devicestats", [Dev_or_Path "path"], [OBool "zero"];
+    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>.
+
+If you want to reset stats to zero after reading them, use option: zero:true." };
+
 ]
 
 (* Non-API meta-commands available only in guestfish.
-- 
2.1.0




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