[PATCH 4/7] util: virfile: Rewrite matching of FUSE-based shared filesystems

[Peter Krempa]

'virFileIsSharedFixFUSE' was used to update the 'f_type' field for
certain shared filesystem types.

This patch renames it to 'virFileIsSharedFsFUSE' and makes it directly
return whether the FUSE filesystem is shared or not and simplifies
additions to the list of shared FUSE filesystems.

Signed-off-by: Peter Krempa <pkrempa at redhat.com>
---
 src/util/virfile.c | 54 ++++++++++++++++++++++++++++------------------
 1 file changed, 33 insertions(+), 21 deletions(-)

diff --git a/src/util/virfile.c b/src/util/virfile.c
index a8443acf8d..33a3ffe8f7 100644
--- a/src/util/virfile.c
+++ b/src/util/virfile.c
@@ -3324,17 +3324,27 @@ virFileRemoveLastComponent(char *path)

 # define PROC_MOUNTS "/proc/mounts"

+
+struct virFileSharedFsData {
+    const char *mnttype;
+    unsigned int fstype;
+};
+
+static const struct virFileSharedFsData virFileSharedFsFUSE[] = {
+    { .mnttype = "fuse.glusterfs", .fstype = VIR_FILE_SHFS_GFS2 },
+    { .mnttype = "fuse.quobyte", .fstype = VIR_FILE_SHFS_QB },
+};
+
 static int
-virFileIsSharedFixFUSE(const char *path,
-                       long long *f_type)
+virFileIsSharedFsFUSE(const char *path,
+                      unsigned int fstypes)
 {
     FILE *f = NULL;
     struct mntent mb;
     char mntbuf[1024];
-    char *mntDir = NULL;
-    char *mntType = NULL;
     g_autofree char *canonPath = NULL;
     size_t maxMatching = 0;
+    bool isShared = false;

     if (!(canonPath = virFileCanonicalizePath(path))) {
         virReportSystemError(errno, _("unable to canonicalize %s"), path);
@@ -3359,28 +3369,30 @@ virFileIsSharedFixFUSE(const char *path,
             continue;

         if (len > maxMatching) {
+            size_t i;
+            bool found = false;
+
+            for (i = 0; i < G_N_ELEMENTS(virFileSharedFsFUSE); i++) {
+                if (STREQ_NULLABLE(mb.mnt_type, virFileSharedFsFUSE[i].mnttype) &&
+                    (fstypes & virFileSharedFsFUSE[i].fstype) > 0) {
+                    found = true;
+                    break;
+                }
+            }
+
+            VIR_DEBUG("Updating shared='%d' for mountpoint '%s' type '%s'",
+                      found, p, mb.mnt_type);
+
+            isShared = found;
             maxMatching = len;
-            VIR_FREE(mntType);
-            VIR_FREE(mntDir);
-            mntDir = g_strdup(mb.mnt_dir);
-            mntType = g_strdup(mb.mnt_type);
         }
     }

     endmntent(f);

-    if (STREQ_NULLABLE(mntType, "fuse.glusterfs")) {
-        VIR_DEBUG("Found gluster FUSE mountpoint=%s for path=%s. "
-                  "Fixing shared FS type", mntDir, canonPath);
-        *f_type = GFS2_MAGIC;
-    } else if (STREQ_NULLABLE(mntType, "fuse.quobyte")) {
-        VIR_DEBUG("Found Quobyte FUSE mountpoint=%s for path=%s. "
-                  "Fixing shared FS type", mntDir, canonPath);
-        *f_type = QB_MAGIC;
-    }
+    if (isShared)
+        return 1;

-    VIR_FREE(mntType);
-    VIR_FREE(mntDir);
     return 0;
 }

@@ -3432,8 +3444,8 @@ virFileIsSharedFSType(const char *path,
     f_type = sb.f_type;

     if (f_type == FUSE_SUPER_MAGIC) {
-        VIR_DEBUG("Found FUSE mount for path=%s. Trying to fix it", path);
-        virFileIsSharedFixFUSE(path, &f_type);
+        VIR_DEBUG("Found FUSE mount for path=%s", path);
+        return virFileIsSharedFsFUSE(path, fstypes);
     }

     VIR_DEBUG("Check if path %s with FS magic %lld is shared",
-- 
2.37.1