New API: add new api xfs_info

Add xfs_info to show the geometry of the xfs filesystem.

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>

RWMJ:
 - Updated po/POTFILES.
 - Use xfs_ prefix for all struct fields.
 - Return uninitialized fields as -1 / empty string.
 - Copyedit the description.

1 files changed, 355 insertions, 0 deletions

diff --git a/daemon/xfs.c b/daemon/xfs.c
new file mode 100644
index 00000000..3efc14f7
--- /dev/null
+++ b/daemon/xfs.c
@@ -0,0 +1,355 @@
+/* libguestfs - the guestfsd daemon
+ * Copyright (C) 2012 Fujitsu Limited.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <inttypes.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "daemon.h"
+#include "actions.h"
+#include "optgroups.h"
+
+int
+optgroup_xfs_available (void)
+{
+  return prog_exists ("mkfs.xfs");
+}
+
+static char *
+split_strdup (char *string)
+{
+  char *end = string;
+  while (*end != ' ' && *end != ',' && *end != '\0') end++;
+  size_t len = end - string;
+  char *ret = malloc (len + 1);
+  if (!ret) {
+    reply_with_perror ("malloc");
+    return NULL;
+  }
+  strncpy (ret, string, len);
+  ret[len] = '\0';
+  return ret;
+}
+
+static int
+parse_uint32 (uint32_t *ret, const char *str)
+{
+  uint32_t r;
+
+  if (sscanf (str, "%" SCNu32, &r) != 1) {
+    reply_with_error ("cannot parse numeric field from isoinfo: %s", str);
+    return -1;
+  }
+
+  *ret = r;
+  return 0;
+}
+
+static int
+parse_uint64 (uint64_t *ret, const char *str)
+{
+  uint64_t r;
+
+  if (sscanf (str, "%" SCNu64, &r) != 1) {
+    reply_with_error ("cannot parse numeric field from isoinfo: %s", str);
+    return -1;
+  }
+
+  *ret = r;
+  return 0;
+}
+
+/* Typical crazy output from the xfs_info command:
+ *
+ * meta-data=/dev/sda1              isize=256    agcount=4, agsize=6392 blks
+ *          =                       sectsz=512   attr=2
+ * data     =                       bsize=4096   blocks=25568, imaxpct=25
+ *          =                       sunit=0      swidth=0 blks
+ * naming   =version 2              bsize=4096   ascii-ci=0
+ * log      =internal               bsize=4096   blocks=1200, version=2
+ *          =                       sectsz=512   sunit=0 blks, lazy-count=1
+ * realtime =none                   extsz=4096   blocks=0, rtextents=0
+ *
+ * We may need to revisit this parsing code if the output changes
+ * in future.
+ */
+static guestfs_int_xfsinfo *
+parse_xfs_info (char **lines)
+{
+  guestfs_int_xfsinfo *ret;
+  char *buf = NULL, *p;
+  size_t i;
+
+  ret = malloc (sizeof *ret);
+  if (ret == NULL) {
+    reply_with_error ("malloc");
+    return NULL;
+  }
+
+  /* Initialize fields to NULL or -1 so the caller can tell which fields
+   * were updated in the code below.
+   */
+  ret->xfs_mntpoint = NULL;
+  ret->xfs_inodesize = -1;
+  ret->xfs_agcount = -1;
+  ret->xfs_agsize = -1;
+  ret->xfs_sectsize = -1;
+  ret->xfs_attr = -1;
+  ret->xfs_blocksize = -1;
+  ret->xfs_datablocks = -1;
+  ret->xfs_imaxpct = -1;
+  ret->xfs_sunit = -1;
+  ret->xfs_swidth = -1;
+  ret->xfs_dirversion = -1;
+  ret->xfs_dirblocksize = -1;
+  ret->xfs_cimode = -1;
+  ret->xfs_logname = NULL;
+  ret->xfs_logblocksize = -1;
+  ret->xfs_logblocks = -1;
+  ret->xfs_logversion = -1;
+  ret->xfs_logsectsize = -1;
+  ret->xfs_logsunit = -1;
+  ret->xfs_lazycount = -1;
+  ret->xfs_rtname = NULL;
+  ret->xfs_rtextsize = -1;
+  ret->xfs_rtblocks = -1;
+  ret->xfs_rtextents = -1;
+
+  for (i = 0; lines[i] != NULL; ++i) {
+    if ((p = strstr (lines[i], "meta-data="))) {
+      ret->xfs_mntpoint = split_strdup (p + 10);
+      if (ret->xfs_mntpoint == NULL) goto error;
+    }
+    if ((p = strstr (lines[i], "isize="))) {
+      buf = split_strdup (p + 6);
+      if (buf == NULL) goto error;
+      if (parse_uint32 (&ret->xfs_inodesize, buf) == -1)
+        goto error;
+      free (buf);
+    }
+    if ((p = strstr (lines[i], "agcount="))) {
+      buf = split_strdup (p + 8);
+      if (buf == NULL) goto error;
+      if (parse_uint32 (&ret->xfs_agcount, buf) == -1)
+        goto error;
+      free (buf);
+    }
+    if ((p = strstr (lines[i], "agsize="))) {
+      buf = split_strdup (p + 7);
+      if (buf == NULL) goto error;
+      if (parse_uint32 (&ret->xfs_agsize, buf) == -1)
+        goto error;
+      free (buf);
+    }
+    if ((p = strstr (lines[i], "sectsz="))) {
+      buf = split_strdup (p + 7);
+      if (buf == NULL) goto error;
+      if (i == 1) {
+        if (parse_uint32 (&ret->xfs_sectsize, buf) == -1)
+          goto error;
+        free (buf);
+      } else if (i == 6) {
+        if (parse_uint32 (&ret->xfs_logsectsize, buf) == -1)
+          goto error;
+        free (buf);
+      } else goto error;
+    }
+    if ((p = strstr (lines[i], "attr="))) {
+      buf = split_strdup (p + 5);
+      if (buf == NULL) goto error;
+      if (parse_uint32 (&ret->xfs_attr, buf) == -1)
+        goto error;
+      free (buf);
+    }
+    if ((p = strstr (lines[i], "bsize="))) {
+      buf = split_strdup (p + 6);
+      if (buf == NULL) goto error;
+      if (i == 2) {
+        if (parse_uint32 (&ret->xfs_blocksize, buf) == -1)
+          goto error;
+        free (buf);
+      } else if (i == 4) {
+        if (parse_uint32 (&ret->xfs_dirblocksize, buf) == -1)
+          goto error;
+        free (buf);
+      } else if (i == 5) {
+        if (parse_uint32 (&ret->xfs_logblocksize, buf) == -1)
+          goto error;
+        free (buf);
+      } else goto error;
+    }
+    if ((p = strstr (lines[i], "blocks="))) {
+      buf = split_strdup (p + 7);
+      if (buf == NULL) goto error;
+      if (i == 2) {
+        if (parse_uint64 (&ret->xfs_datablocks, buf) == -1)
+          goto error;
+        free (buf);
+      } else if (i == 5) {
+        if (parse_uint32 (&ret->xfs_logblocks, buf) == -1)
+          goto error;
+        free (buf);
+      } else if (i == 7) {
+        if (parse_uint64 (&ret->xfs_rtblocks, buf) == -1)
+          goto error;
+        free (buf);
+      } else goto error;
+    }
+    if ((p = strstr (lines[i], "imaxpct="))) {
+      buf = split_strdup (p + 8);
+      if (buf == NULL) goto error;
+      if (parse_uint32 (&ret->xfs_imaxpct, buf) == -1)
+        goto error;
+      free (buf);
+    }
+    if ((p = strstr (lines[i], "sunit="))) {
+      buf = split_strdup (p + 6);
+      if (buf == NULL) goto error;
+      if (i == 3) {
+        if (parse_uint32 (&ret->xfs_sunit, buf) == -1)
+          goto error;
+        free (buf);
+      } else if (i == 6) {
+        if (parse_uint32 (&ret->xfs_logsunit, buf) == -1)
+          goto error;
+        free (buf);
+      } else goto error;
+    }
+    if ((p = strstr (lines[i], "swidth="))) {
+      buf = split_strdup (p + 7);
+      if (buf == NULL) goto error;
+      if (parse_uint32 (&ret->xfs_swidth, buf) == -1)
+        goto error;
+      free (buf);
+    }
+    if ((p = strstr (lines[i], "naming   =version "))) {
+      buf = split_strdup (p + 18);
+      if (buf == NULL) goto error;
+      if (parse_uint32 (&ret->xfs_dirversion, buf) == -1)
+        goto error;
+      free (buf);
+    }
+    if ((p = strstr (lines[i], "ascii-ci="))) {
+      buf = split_strdup (p + 9);
+      if (buf == NULL) goto error;
+      if (parse_uint32 (&ret->xfs_cimode, buf) == -1)
+        goto error;
+      free (buf);
+    }
+    if ((p = strstr (lines[i], "log      ="))) {
+      ret->xfs_logname = split_strdup (p + 10);
+      if (ret->xfs_logname == NULL) goto error;
+    }
+    if ((p = strstr (lines[i], "version="))) {
+      buf = split_strdup (p + 8);
+      if (buf == NULL) goto error;
+      if (parse_uint32 (&ret->xfs_logversion, buf) == -1)
+        goto error;
+      free (buf);
+    }
+    if ((p = strstr (lines[i], "lazy-count="))) {
+      buf = split_strdup (p + 11);
+      if (buf == NULL) goto error;
+      if (parse_uint32 (&ret->xfs_lazycount, buf) == -1)
+        goto error;
+      free (buf);
+    }
+    if ((p = strstr (lines[i], "realtime ="))) {
+      ret->xfs_rtname = split_strdup (p + 10);
+      if (ret->xfs_rtname == NULL) goto error;
+    }
+    if ((p = strstr (lines[i], "rtextents="))) {
+      buf = split_strdup (p + 10);
+      if (buf == NULL) goto error;
+      if (parse_uint64 (&ret->xfs_rtextents, buf) == -1)
+        goto error;
+      free (buf);
+    }
+  }
+
+  if (ret->xfs_mntpoint == NULL) {
+    ret->xfs_mntpoint = strdup ("");
+    if (ret->xfs_mntpoint == NULL) goto error;
+  }
+  if (ret->xfs_logname == NULL) {
+    ret->xfs_logname = strdup ("");
+    if (ret->xfs_logname == NULL) goto error;
+  }
+  if (ret->xfs_rtname == NULL) {
+    ret->xfs_rtname = strdup ("");
+    if (ret->xfs_rtname == NULL) goto error;
+  }
+
+  return ret;
+
+error:
+  free (buf);
+  free (ret->xfs_mntpoint);
+  free (ret->xfs_logname);
+  free (ret->xfs_rtname);
+  free (ret);
+  return NULL;
+}
+
+guestfs_int_xfsinfo *
+do_xfs_info (const char *path)
+{
+  int r;
+  char *buf;
+  char *out = NULL, *err = NULL;
+  char **lines = NULL;
+  guestfs_int_xfsinfo *ret = NULL;
+
+  if (do_is_dir (path)) {
+    buf = sysroot_path (path);
+    if (!buf) {
+      reply_with_perror ("malloc");
+      return NULL;
+    }
+  } else {
+    buf = strdup(path);
+    if (!buf) {
+      reply_with_perror ("strdup");
+      return NULL;
+    }
+  }
+
+  r = command (&out, &err, "xfs_info", buf, NULL);
+  free (buf);
+  if (r == -1) {
+    reply_with_error ("%s", err);
+    goto error;
+  }
+
+  lines = split_lines (out);
+  if (lines == NULL)
+    goto error;
+
+  ret = parse_xfs_info (lines);
+
+error:
+  free (err);
+  free (out);
+  if (lines)
+    free_strings (lines);
+  return ret;
+}