lib: Make pcre, libmagic and hivex libraries optional.

This change makes these libraries optional.  If they are not
available at compile time then certain core API features will
be disabled (see below).

This also changes PCRE detection to use pkg-config instead
of the ad hoc autoconf checks.

The large inspect.c file has been split out into separate
function-specific files.

  file-architecture: requires pcre & libmagic
  inspection: requires pcre & hivex

1 files changed, 169 insertions, 0 deletions

diff --git a/src/listfs.c b/src/listfs.c
new file mode 100644
index 00000000..a89cd9bd
--- /dev/null
+++ b/src/listfs.c
@@ -0,0 +1,169 @@
+/* libguestfs
+ * Copyright (C) 2010 Red Hat Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; 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 <stdint.h>
+#include <inttypes.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include "guestfs.h"
+#include "guestfs-internal.h"
+#include "guestfs-internal-actions.h"
+#include "guestfs_protocol.h"
+
+/* List filesystems.
+ *
+ * The current implementation just uses guestfs_vfs_type and doesn't
+ * try mounting anything, but we reserve the right in future to try
+ * mounting filesystems.
+ */
+
+static void remove_from_list (char **list, const char *item);
+static void check_with_vfs_type (guestfs_h *g, const char *dev, char ***ret, size_t *ret_size);
+
+char **
+guestfs__list_filesystems (guestfs_h *g)
+{
+  size_t i;
+  char **ret;
+  size_t ret_size;
+
+  ret = safe_malloc (g, sizeof (char *));
+  ret[0] = NULL;
+  ret_size = 0;
+
+  /* Look to see if any devices directly contain filesystems
+   * (RHBZ#590167).  However vfs-type will fail to tell us anything
+   * useful about devices which just contain partitions, so we also
+   * get the list of partitions and exclude the corresponding devices
+   * by using part-to-dev.
+   */
+  char **devices;
+  devices = guestfs_list_devices (g);
+  if (devices == NULL) {
+    guestfs___free_string_list (ret);
+    return NULL;
+  }
+  char **partitions;
+  partitions = guestfs_list_partitions (g);
+  if (partitions == NULL) {
+    guestfs___free_string_list (devices);
+    guestfs___free_string_list (ret);
+    return NULL;
+  }
+
+  for (i = 0; partitions[i] != NULL; ++i) {
+    char *dev = guestfs_part_to_dev (g, partitions[i]);
+    if (dev)
+      remove_from_list (devices, dev);
+    free (dev);
+  }
+
+  /* Use vfs-type to check for filesystems on devices. */
+  for (i = 0; devices[i] != NULL; ++i)
+    check_with_vfs_type (g, devices[i], &ret, &ret_size);
+  guestfs___free_string_list (devices);
+
+  /* Use vfs-type to check for filesystems on partitions. */
+  for (i = 0; partitions[i] != NULL; ++i)
+    check_with_vfs_type (g, partitions[i], &ret, &ret_size);
+  guestfs___free_string_list (partitions);
+
+  if (guestfs___feature_available (g, "lvm2")) {
+    /* Use vfs-type to check for filesystems on LVs. */
+    char **lvs;
+    lvs = guestfs_lvs (g);
+    if (lvs == NULL) {
+      guestfs___free_string_list (ret);
+      return NULL;
+    }
+
+    for (i = 0; lvs[i] != NULL; ++i)
+      check_with_vfs_type (g, lvs[i], &ret, &ret_size);
+    guestfs___free_string_list (lvs);
+  }
+
+  return ret;
+}
+
+/* If 'item' occurs in 'list', remove and free it. */
+static void
+remove_from_list (char **list, const char *item)
+{
+  size_t i;
+
+  for (i = 0; list[i] != NULL; ++i)
+    if (STREQ (list[i], item)) {
+      free (list[i]);
+      for (; list[i+1] != NULL; ++i)
+        list[i] = list[i+1];
+      list[i] = NULL;
+      return;
+    }
+}
+
+/* Use vfs-type to look for a filesystem of some sort on 'dev'.
+ * Apart from some types which we ignore, add the result to the
+ * 'ret' string list.
+ */
+static void
+check_with_vfs_type (guestfs_h *g, const char *device,
+                     char ***ret, size_t *ret_size)
+{
+  char *v;
+
+  guestfs_error_handler_cb old_error_cb = g->error_cb;
+  g->error_cb = NULL;
+  char *vfs_type = guestfs_vfs_type (g, device);
+  g->error_cb = old_error_cb;
+
+  if (!vfs_type)
+    v = safe_strdup (g, "unknown");
+  else {
+    /* Ignore all "*_member" strings.  In libblkid these are returned
+     * for things which are members of some RAID or LVM set, most
+     * importantly "LVM2_member" which is a PV.
+     */
+    size_t n = strlen (vfs_type);
+    if (n >= 7 && STREQ (&vfs_type[n-7], "_member")) {
+      free (vfs_type);
+      return;
+    }
+
+    /* Ignore LUKS-encrypted partitions.  These are also containers. */
+    if (STREQ (vfs_type, "crypto_LUKS")) {
+      free (vfs_type);
+      return;
+    }
+
+    v = vfs_type;
+  }
+
+  /* Extend the return array. */
+  size_t i = *ret_size;
+  *ret_size += 2;
+  *ret = safe_realloc (g, *ret, (*ret_size + 1) * sizeof (char *));
+  (*ret)[i] = safe_strdup (g, device);
+  (*ret)[i+1] = v;
+  (*ret)[i+2] = NULL;
+}