dmeventd: use dm_mountinfo_read

Reuse mountinfo reading code from libdm.

diff --git a/daemons/dmeventd/plugins/thin/dmeventd_thin.c b/daemons/dmeventd/plugins/thin/dmeventd_thin.c
index 95ab27a625ae0b46d86c130708919962232c83ca..f32424ad83989ec9e84b92e10cd555414ca128e3 100644 (file)
--- a/daemons/dmeventd/plugins/thin/dmeventd_thin.c
+++ b/daemons/dmeventd/plugins/thin/dmeventd_thin.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2011-2012 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2011-2013 Red Hat, Inc. All rights reserved.
  *
  * This file is part of LVM2.
  *
@@ -53,53 +53,6 @@ struct dso_state {
 #  define MKDEV(x,y) makedev((x),(y))
 #endif
 
-/* Macros to make string defines */
-#define TO_STRING_EXP(A) #A
-#define TO_STRING(A) TO_STRING_EXP(A)
-
-static int _is_octal(int a)
-{
-       return (((a) & ~7) == '0');
-}
-
-/* Convert mangled mountinfo into normal ASCII string */
-static void _unmangle_mountinfo_string(const char *src, char *buf)
-{
-       if (!src)
-               return;
-
-       while (*src) {
-               if ((*src == '\\') &&
-                   _is_octal(src[1]) && _is_octal(src[2]) && _is_octal(src[3])) {
-                       *buf++ = 64 * (src[1] & 7) + 8 * (src[2] & 7) + (src[3] & 7);
-                       src += 4;
-               } else
-                       *buf++ = *src++;
-       }
-       *buf = '\0';
-}
-
-/* Parse one line of mountinfo */
-static int _parse_mountinfo_line(const char *line, unsigned *maj, unsigned *min, char *buf)
-{
-       char root[PATH_MAX + 1];
-       char target[PATH_MAX + 1];
-
-       /* TODO: maybe detect availability of  %ms  glib support ? */
-       if (sscanf(line, "%*u %*u %u:%u %" TO_STRING(PATH_MAX)
-                  "s %" TO_STRING(PATH_MAX) "s",
-                  maj, min, root, target) < 4)
-               return 0;
-
-       _unmangle_mountinfo_string(target, buf);
-
-#if THIN_DEBUG
-       syslog(LOG_DEBUG, "Mounted  %u:%u  %s", *maj, *min, buf);
-#endif
-
-       return 1;
-}
-
 /* Get dependencies for device, and try to find matching device */
 static int _has_deps(const char *name, int tp_major, int tp_minor, int *dev_minor)
 {
@@ -238,62 +191,62 @@ static int _run(const char *cmd, ...)
        return 1; /* all good */
 }
 
+struct mountinfo_s {
+       struct dm_info info;
+       dm_bitset_t minors; /* Bitset for active thin pool minors */
+       const char *device;
+};
+
+static int _umount_device(char *buffer, unsigned major, unsigned minor,
+                         char *target, void *cb_data)
+{
+       struct mountinfo_s *data = cb_data;
+
+       if ((major == data->info.major) && dm_bit(data->minors, minor)) {
+               syslog(LOG_INFO, "Unmounting thin volume %s from %s.\n",
+                      data->device, target);
+               if (!_run(UMOUNT_COMMAND, "-fl", target, NULL))
+                       syslog(LOG_ERR, "Failed to umount thin %s from %s: %s.\n",
+                              data->device, target, strerror(errno));
+       }
+
+       return 1;
+}
+
 /*
  * Find all thin pool users and try to umount them.
  * TODO: work with read-only thin pool support
  */
 static void _umount(struct dm_task *dmt, const char *device)
 {
-       static const char mountinfo[] = "/proc/self/mountinfo";
        static const size_t MINORS = 4096;
-       FILE *minfo = NULL;
-       char buffer[4096];
-       char target[PATH_MAX];
-       struct dm_info info;
-       unsigned maj, min;
-       dm_bitset_t minors; /* Bitset for active thin pool minors */
+       struct mountinfo_s data = {
+               .device = device,
+       };
 
-       if (!dm_task_get_info(dmt, &info))
+       if (!dm_task_get_info(dmt, &data.info))
                return;
 
        dmeventd_lvm2_unlock();
 
-       if (!(minors = dm_bitset_create(NULL, MINORS))) {
+       if (!(data.minors = dm_bitset_create(NULL, MINORS))) {
                syslog(LOG_ERR, "Failed to allocate bitset. Not unmounting %s.\n", device);
                goto out;
        }
 
-       if (!(minfo = fopen(mountinfo, "r"))) {
-               syslog(LOG_ERR, "Could not read %s. Not umounting %s.\n", mountinfo, device);
-               goto out;
-       }
-
-       if (!_find_all_devs(minors, info.major, info.minor)) {
+       if (!_find_all_devs(data.minors, data.info.major, data.info.minor)) {
                syslog(LOG_ERR, "Failed to detect mounted volumes for %s.\n", device);
                goto out;
        }
 
-       while (!feof(minfo)) {
-               /* read mountinfo line */
-               if (!fgets(buffer, sizeof(buffer), minfo))
-                       break; /* eof, likely */
-
-               if (_parse_mountinfo_line(buffer, &maj, &min, target) &&
-                   (maj == info.major) && dm_bit(minors, min)) {
-                       syslog(LOG_INFO, "Unmounting thin volume %s from %s.\n",
-                              device, target);
-                       if (!_run(UMOUNT_COMMAND, "-fl", target, NULL))
-                               syslog(LOG_ERR, "Failed to umount thin %s from %s: %s.\n",
-                                      device, target, strerror(errno));
-               }
+       if (!dm_mountinfo_read(_umount_device, &data)) {
+               syslog(LOG_ERR, "Could not parse mountinfo file.\n");
+               goto out;
        }
 
 out:
-       if (minfo && fclose(minfo))
-               syslog(LOG_ERR, "Failed to close %s\n", mountinfo);
-
-       if (minors)
-               dm_bitset_destroy(minors);
+       if (data.minors)
+               dm_bitset_destroy(data.minors);
        dmeventd_lvm2_lock();
 }