X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=daemon%2Fext2.c;h=b7ce627e33857d58e95b552120e0c5e6b6a85a3e;hp=f768440d796532857eb68628c37173c51b8c9b46;hb=d600342b7d29c0176ff96a7807ebb38303ecb3a6;hpb=9a8889e4d0c532b9f77af3a9cc7aae06adebfb83

diff --git a/daemon/ext2.c b/daemon/ext2.c
index f768440..b7ce627 100644
--- a/daemon/ext2.c
+++ b/daemon/ext2.c
@@ -20,6 +20,8 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <inttypes.h>
+#include <string.h>
 #include <unistd.h>
 
 #include "../src/guestfs_protocol.h"
@@ -27,6 +29,35 @@
 #include "c-ctype.h"
 #include "actions.h"
 
+/* Confirmed this is true up to ext4 from the Linux sources. */
+#define EXT2_LABEL_MAX 16
+
+/* Choose which tools like mke2fs to use.  For RHEL 5 (only) there
+ * is a special set of tools which support ext2/3/4.  eg. On RHEL 5,
+ * mke2fs only supports ext2/3, but mke4fs supports ext2/3/4.
+ *
+ * We specify e4fsprogs in the package list to ensure it is loaded
+ * if it exists.
+ */
+static int
+e2prog (char *name)
+{
+  char *p = strstr (name, "e2");
+  if (!p) return 0;
+  p++;
+
+  *p = '4';
+  if (prog_exists (name))
+    return 0;
+
+  *p = '2';
+  if (prog_exists (name))
+    return 0;
+
+  reply_with_error ("cannot find required program %s", name);
+  return -1;
+}
+
 char **
 do_tune2fs_l (const char *device)
 {
@@ -36,9 +67,13 @@ do_tune2fs_l (const char *device)
   char **ret = NULL;
   int size = 0, alloc = 0;
 
-  r = command (&out, &err, "/sbin/tune2fs", "-l", device, NULL);
+  char prog[] = "tune2fs";
+  if (e2prog (prog) == -1)
+    return NULL;
+
+  r = command (&out, &err, prog, "-l", device, NULL);
   if (r == -1) {
-    reply_with_error ("tune2fs: %s", err);
+    reply_with_error ("%s", err);
     free (err);
     free (out);
     return NULL;
@@ -48,11 +83,11 @@ do_tune2fs_l (const char *device)
   p = out;
 
   /* Discard the first line if it contains "tune2fs ...". */
-  if (STREQLEN (p, "tune2fs ", 8)) {
+  if (STRPREFIX (p, "tune2fs ") || STRPREFIX (p, "tune4fs ")) {
     p = strchr (p, '\n');
     if (p) p++;
     else {
-      reply_with_error ("tune2fs: truncated output");
+      reply_with_error ("truncated output");
       free (out);
       return NULL;
     }
@@ -120,9 +155,19 @@ do_set_e2label (const char *device, const char *label)
   int r;
   char *err;
 
-  r = command (NULL, &err, "/sbin/e2label", device, label, NULL);
+  char prog[] = "e2label";
+  if (e2prog (prog) == -1)
+    return -1;
+
+  if (strlen (label) > EXT2_LABEL_MAX) {
+    reply_with_error ("%s: ext2 labels are limited to %d bytes",
+                      label, EXT2_LABEL_MAX);
+    return -1;
+  }
+
+  r = command (NULL, &err, prog, device, label, NULL);
   if (r == -1) {
-    reply_with_error ("e2label: %s", err);
+    reply_with_error ("%s", err);
     free (err);
     return -1;
   }
@@ -134,25 +179,7 @@ do_set_e2label (const char *device, const char *label)
 char *
 do_get_e2label (const char *device)
 {
-  int r, len;
-  char *out, *err;
-
-  r = command (&out, &err, "/sbin/e2label", device, NULL);
-  if (r == -1) {
-    reply_with_error ("e2label: %s", err);
-    free (out);
-    free (err);
-    return NULL;
-  }
-
-  free (err);
-
-  /* Remove any trailing \n from the label. */
-  len = strlen (out);
-  if (len > 0 && out[len-1] == '\n')
-    out[len-1] = '\0';
-
-  return out;			/* caller frees */
+  return do_vfs_label (device);
 }
 
 int
@@ -161,9 +188,13 @@ do_set_e2uuid (const char *device, const char *uuid)
   int r;
   char *err;
 
-  r = command (NULL, &err, "/sbin/tune2fs", "-U", uuid, device, NULL);
+  char prog[] = "tune2fs";
+  if (e2prog (prog) == -1)
+    return -1;
+
+  r = command (NULL, &err, prog, "-U", uuid, device, NULL);
   if (r == -1) {
-    reply_with_error ("tune2fs -U: %s", err);
+    reply_with_error ("%s", err);
     free (err);
     return -1;
   }
@@ -175,73 +206,57 @@ do_set_e2uuid (const char *device, const char *uuid)
 char *
 do_get_e2uuid (const char *device)
 {
+  return do_vfs_uuid (device);
+}
+
+int
+do_resize2fs (const char *device)
+{
+  char *err;
   int r;
-  char *out, *err, *p, *q;
 
-  /* It's not so straightforward to get the volume UUID.  We have
-   * to use tune2fs -l and then look for a particular string in
-   * the output.
-   */
+  char prog[] = "resize2fs";
+  if (e2prog (prog) == -1)
+    return -1;
 
-  r = command (&out, &err, "/sbin/tune2fs", "-l", device, NULL);
+  r = command (NULL, &err, prog, device, NULL);
   if (r == -1) {
-    reply_with_error ("tune2fs -l: %s", err);
-    free (out);
+    reply_with_error ("%s", err);
     free (err);
-    return NULL;
+    return -1;
   }
 
   free (err);
-
-  /* Look for /\nFilesystem UUID:\s+/ in the output. */
-  p = strstr (out, "\nFilesystem UUID:");
-  if (p == NULL) {
-    reply_with_error ("no Filesystem UUID in the output of tune2fs -l");
-    free (out);
-    return NULL;
-  }
-
-  p += 17;
-  while (*p && c_isspace (*p))
-    p++;
-  if (!*p) {
-    reply_with_error ("malformed Filesystem UUID in the output of tune2fs -l");
-    free (out);
-    return NULL;
-  }
-
-  /* Now 'p' hopefully points to the start of the UUID. */
-  q = p;
-  while (*q && (c_isxdigit (*q) || *q == '-'))
-    q++;
-  if (!*q) {
-    reply_with_error ("malformed Filesystem UUID in the output of tune2fs -l");
-    free (out);
-    return NULL;
-  }
-
-  *q = '\0';
-
-  p = strdup (p);
-  if (!p) {
-    reply_with_perror ("strdup");
-    free (out);
-    return NULL;
-  }
-
-  free (out);
-  return p;			/* caller frees */
+  return 0;
 }
 
 int
-do_resize2fs (const char *device)
+do_resize2fs_size (const char *device, int64_t size)
 {
   char *err;
   int r;
 
-  r = command (NULL, &err, "/sbin/resize2fs", device, NULL);
+  char prog[] = "resize2fs";
+  if (e2prog (prog) == -1)
+    return -1;
+
+  /* resize2fs itself may impose additional limits.  Since we are
+   * going to use the 'K' suffix however we can only work with whole
+   * kilobytes.
+   */
+  if (size & 1023) {
+    reply_with_error ("%" PRIi64 ": size must be a round number of kilobytes",
+                      size);
+    return -1;
+  }
+  size /= 1024;
+
+  char buf[32];
+  snprintf (buf, sizeof buf, "%" PRIi64 "K", size);
+
+  r = command (NULL, &err, prog, device, buf, NULL);
   if (r == -1) {
-    reply_with_error ("resize2fs: %s", err);
+    reply_with_error ("%s", err);
     free (err);
     return -1;
   }
@@ -256,9 +271,20 @@ do_e2fsck_f (const char *device)
   char *err;
   int r;
 
-  r = command (NULL, &err, "/sbin/e2fsck", "-p", "-f", device, NULL);
-  if (r == -1) {
-    reply_with_error ("e2fsck: %s", err);
+  char prog[] = "e2fsck";
+  if (e2prog (prog) == -1)
+    return -1;
+
+  /* 0 = no errors, 1 = errors corrected.
+   *
+   * >= 4 means uncorrected or other errors.
+   *
+   * 2, 3 means errors were corrected and we require a reboot.  This is
+   * a difficult corner case.
+   */
+  r = commandr (NULL, &err, prog, "-p", "-f", device, NULL);
+  if (r == -1 || r >= 2) {
+    reply_with_error ("%s", err);
     free (err);
     return -1;
   }
@@ -273,14 +299,18 @@ do_mke2journal (int blocksize, const char *device)
   char *err;
   int r;
 
+  char prog[] = "mke2fs";
+  if (e2prog (prog) == -1)
+    return -1;
+
   char blocksize_s[32];
   snprintf (blocksize_s, sizeof blocksize_s, "%d", blocksize);
 
   r = command (NULL, &err,
-               "/sbin/mke2fs", "-O", "journal_dev", "-b", blocksize_s,
+               prog, "-O", "journal_dev", "-b", blocksize_s,
                device, NULL);
   if (r == -1) {
-    reply_with_error ("mke2journal: %s", err);
+    reply_with_error ("%s", err);
     free (err);
     return -1;
   }
@@ -295,15 +325,25 @@ do_mke2journal_L (int blocksize, const char *label, const char *device)
   char *err;
   int r;
 
+  char prog[] = "mke2fs";
+  if (e2prog (prog) == -1)
+    return -1;
+
+  if (strlen (label) > EXT2_LABEL_MAX) {
+    reply_with_error ("%s: ext2 labels are limited to %d bytes",
+                      label, EXT2_LABEL_MAX);
+    return -1;
+  }
+
   char blocksize_s[32];
   snprintf (blocksize_s, sizeof blocksize_s, "%d", blocksize);
 
   r = command (NULL, &err,
-               "/sbin/mke2fs", "-O", "journal_dev", "-b", blocksize_s,
+               prog, "-O", "journal_dev", "-b", blocksize_s,
                "-L", label,
                device, NULL);
   if (r == -1) {
-    reply_with_error ("mke2journal_L: %s", err);
+    reply_with_error ("%s", err);
     free (err);
     return -1;
   }
@@ -318,15 +358,19 @@ do_mke2journal_U (int blocksize, const char *uuid, const char *device)
   char *err;
   int r;
 
+  char prog[] = "mke2fs";
+  if (e2prog (prog) == -1)
+    return -1;
+
   char blocksize_s[32];
   snprintf (blocksize_s, sizeof blocksize_s, "%d", blocksize);
 
   r = command (NULL, &err,
-               "/sbin/mke2fs", "-O", "journal_dev", "-b", blocksize_s,
+               prog, "-O", "journal_dev", "-b", blocksize_s,
                "-U", uuid,
                device, NULL);
   if (r == -1) {
-    reply_with_error ("mke2journal_U: %s", err);
+    reply_with_error ("%s", err);
     free (err);
     return -1;
   }
@@ -335,40 +379,6 @@ do_mke2journal_U (int blocksize, const char *uuid, const char *device)
   return 0;
 }
 
-/* Run mke2fs to create a filesystem of type fstype, where fstype
- * is the string "ext2", "ext3" or "ext4".
- *
- * This is more complex than it seems.
- *
- * On RHEL 5, the -t option was deprecated.  Moreover RHEL <= 5.4
- * systems have a bug where the -t option doesn't work (it doesn't
- * correctly ignore the following argument).
- *
- * On RHEL 5, to create an ext4dev filesystem you have to use
- * the special command /sbin/mke4fs.  This can also create ext2/3
- * using the '-t fstype' option.
- *
- * On Fedora 11+, mke4fs was renamed mke2fs, and it can use the
- * '-t fstype' option to specify the filesystem type.
- *
- * So it seems best to run /sbin/mke4fs if it exists, or /sbin/mke2fs
- * otherwise.  We specify e4fsprogs in the package list to ensure it
- * is loaded if it exists.
- */
-static const char *
-get_mke2fs (void)
-{
-  static const char *const progs[] = { "/sbin/mke4fs", "/sbin/mke2fs", NULL };
-  int i;
-
-  for (i = 0; progs[i]; ++i)
-    if (access (progs[i], F_OK) == 0)
-      return progs[i];
-
-  reply_with_error ("mke2fs: no mke2fs binary found in appliance");
-  return NULL;
-}
-
 int
 do_mke2fs_J (const char *fstype, int blocksize, const char *device,
              const char *journal)
@@ -376,8 +386,9 @@ do_mke2fs_J (const char *fstype, int blocksize, const char *device,
   char *err;
   int r;
 
-  const char *prog = get_mke2fs ();
-  if (!prog) return -1;
+  char prog[] = "mke2fs";
+  if (e2prog (prog) == -1)
+    return -1;
 
   char blocksize_s[32];
   snprintf (blocksize_s, sizeof blocksize_s, "%d", blocksize);
@@ -390,7 +401,7 @@ do_mke2fs_J (const char *fstype, int blocksize, const char *device,
                prog, "-t", fstype, "-J", jdev, "-b", blocksize_s,
                device, NULL);
   if (r == -1) {
-    reply_with_error ("mke2fs_J: %s", err);
+    reply_with_error ("%s", err);
     free (err);
     return -1;
   }
@@ -406,8 +417,15 @@ do_mke2fs_JL (const char *fstype, int blocksize, const char *device,
   char *err;
   int r;
 
-  const char *prog = get_mke2fs ();
-  if (!prog) return -1;
+  char prog[] = "mke2fs";
+  if (e2prog (prog) == -1)
+    return -1;
+
+  if (strlen (label) > EXT2_LABEL_MAX) {
+    reply_with_error ("%s: ext2 labels are limited to %d bytes",
+                      label, EXT2_LABEL_MAX);
+    return -1;
+  }
 
   char blocksize_s[32];
   snprintf (blocksize_s, sizeof blocksize_s, "%d", blocksize);
@@ -420,7 +438,7 @@ do_mke2fs_JL (const char *fstype, int blocksize, const char *device,
                prog, "-t", fstype, "-J", jdev, "-b", blocksize_s,
                device, NULL);
   if (r == -1) {
-    reply_with_error ("mke2fs_JL: %s", err);
+    reply_with_error ("%s", err);
     free (err);
     return -1;
   }
@@ -436,8 +454,9 @@ do_mke2fs_JU (const char *fstype, int blocksize, const char *device,
   char *err;
   int r;
 
-  const char *prog = get_mke2fs ();
-  if (!prog) return -1;
+  char prog[] = "mke2fs";
+  if (e2prog (prog) == -1)
+    return -1;
 
   char blocksize_s[32];
   snprintf (blocksize_s, sizeof blocksize_s, "%d", blocksize);
@@ -450,7 +469,7 @@ do_mke2fs_JU (const char *fstype, int blocksize, const char *device,
                prog, "-t", fstype, "-J", jdev, "-b", blocksize_s,
                device, NULL);
   if (r == -1) {
-    reply_with_error ("mke2fs_JU: %s", err);
+    reply_with_error ("%s", err);
     free (err);
     return -1;
   }