name veritas volume disk groups (#4150)

* name veritas volume disk groups; fixes #4116

* recursive naming of veritas volume groups and local volumes; fixes #4116

* added debugging info to trace it

* positive depth should be given to /dev/vx/dsk not /dev/disk/by-id; fixes #4116

* removed debugging; added separator instead of duplicate name

* add _ before the final component, when there is a prefix

1 files changed, 78 insertions, 39 deletions

diff --git a/src/proc_diskstats.c b/src/proc_diskstats.c
index 3df2bf9e57..5d3d4bc242 100644
--- a/src/proc_diskstats.c
+++ b/src/proc_diskstats.c
@@ -143,6 +143,7 @@ static char *path_to_sys_devices_virtual_block_device = NULL;
 static char *path_to_device_mapper = NULL;
 static char *path_to_device_label = NULL;
 static char *path_to_device_id = NULL;
+static char *path_to_veritas_volume_groups = NULL;
 static int name_disks_by_id = CONFIG_BOOLEAN_NO;
 static int global_bcache_priority_stats_update_every = 0; // disabled by default
 
@@ -308,61 +309,95 @@ static inline int is_major_enabled(int major) {
     return (int)major_configs[major];
 }
 
-static inline int get_disk_name_from_path(const char *path, char *result, size_t result_size, unsigned long major, unsigned long minor, char *disk) {
-    char filename[FILENAME_MAX + 1];
-    int found = 0;
+static inline int get_disk_name_from_path(const char *path, char *result, size_t result_size, unsigned long major, unsigned long minor, char *disk, char *prefix, int depth) {
+    //info("DEVICE-MAPPER ('%s', %lu:%lu): examining directory '%s' (allowed depth %d).", disk, major, minor, path, depth);
 
-    result_size--;
+    int found = 0;
 
     DIR *dir = opendir(path);
     if (!dir) {
-        error("DEVICE-MAPPER ('%s', %lu:%lu): Cannot open directory '%s'. Disabling device-mapper support.", disk, major, minor, path);
-        goto cleanup;
+        error("DEVICE-MAPPER ('%s', %lu:%lu): Cannot open directory '%s'.", disk, major, minor, path);
+        goto failed;
     }
 
     struct dirent *de = NULL;
     while ((de = readdir(dir))) {
-        if(de->d_type != DT_LNK) continue;
+        if(de->d_type == DT_DIR) {
+            if((de->d_name[0] == '.' && de->d_name[1] == '\0') || (de->d_name[0] == '.' && de->d_name[1] == '.' && de->d_name[2] == '\0'))
+                continue;
 
-        snprintfz(filename, FILENAME_MAX, "%s/%s", path, de->d_name);
-        ssize_t len = readlink(filename, result, result_size);
-        if(len <= 0) {
-            error("DEVICE-MAPPER ('%s', %lu:%lu): Cannot read link '%s'.", disk, major, minor, filename);
-            continue;
-        }
+            if(depth <= 0) {
+                error("DEVICE-MAPPER ('%s', %lu:%lu): Depth limit reached for path '%s/%s'. Ignoring path.", disk, major, minor, path, de->d_name);
+                break;
+            }
+            else {
+                char *path_nested = NULL;
+                char *prefix_nested = NULL;
 
-        result[len] = '\0';
-        if(result[0] != '/')
-            snprintfz(filename, FILENAME_MAX, "%s/%s", path, result);
-        else
-            strncpyz(filename, result, FILENAME_MAX);
+                {
+                    char buffer[FILENAME_MAX + 1];
+                    snprintfz(buffer, FILENAME_MAX, "%s/%s", path, de->d_name);
+                    path_nested = strdupz(buffer);
 
-        struct stat sb;
-        if(stat(filename, &sb) == -1) {
-            error("DEVICE-MAPPER ('%s', %lu:%lu): Cannot stat() file '%s'.", disk, major, minor, filename);
-            continue;
-        }
+                    snprintfz(buffer, FILENAME_MAX, "%s%s%s", (prefix)?prefix:"", (prefix)?"_":"", de->d_name);
+                    prefix_nested = strdupz(buffer);
+                }
 
-        if((sb.st_mode & S_IFMT) != S_IFBLK) {
-            // info("DEVICE-MAPPER ('%s', %lu:%lu): file '%s' is not a block device.", disk, major, minor, filename);
-            continue;
-        }
+                found = get_disk_name_from_path(path_nested, result, result_size, major, minor, disk, prefix_nested, depth - 1);
+                freez(path_nested);
+                freez(prefix_nested);
 
-        if(major(sb.st_rdev) != major || minor(sb.st_rdev) != minor) {
-            // info("DEVICE-MAPPER ('%s', %lu:%lu): filename '%s' does not match %lu:%lu.", disk, major, minor, filename, (unsigned long)major(sb.st_rdev), (unsigned long)minor(sb.st_rdev));
-            continue;
+                if(found) break;
+            }
         }
+        else if(de->d_type == DT_LNK || de->d_type == DT_BLK) {
+            char filename[FILENAME_MAX + 1];
+
+            if(de->d_type == DT_LNK) {
+                snprintfz(filename, FILENAME_MAX, "%s/%s", path, de->d_name);
+                ssize_t len = readlink(filename, result, result_size - 1);
+                if(len <= 0) {
+                    error("DEVICE-MAPPER ('%s', %lu:%lu): Cannot read link '%s'.", disk, major, minor, filename);
+                    continue;
+                }
+
+                result[len] = '\0';
+                if(result[0] != '/')
+                    snprintfz(filename, FILENAME_MAX, "%s/%s", path, result);
+                else
+                    strncpyz(filename, result, FILENAME_MAX);
+            }
+            else {
+                snprintfz(filename, FILENAME_MAX, "%s/%s", path, de->d_name);
+            }
+
+            struct stat sb;
+            if(stat(filename, &sb) == -1) {
+                error("DEVICE-MAPPER ('%s', %lu:%lu): Cannot stat() file '%s'.", disk, major, minor, filename);
+                continue;
+            }
 
-        // info("DEVICE-MAPPER ('%s', %lu:%lu): filename '%s' matches.", disk, major, minor, filename);
+            if((sb.st_mode & S_IFMT) != S_IFBLK) {
+                //info("DEVICE-MAPPER ('%s', %lu:%lu): file '%s' is not a block device.", disk, major, minor, filename);
+                continue;
+            }
+
+            if(major(sb.st_rdev) != major || minor(sb.st_rdev) != minor) {
+                //info("DEVICE-MAPPER ('%s', %lu:%lu): filename '%s' does not match %lu:%lu.", disk, major, minor, filename, (unsigned long)major(sb.st_rdev), (unsigned long)minor(sb.st_rdev));
+                continue;
+            }
 
-        strncpy(result, de->d_name, result_size);
-        found = 1;
-        break;
+            //info("DEVICE-MAPPER ('%s', %lu:%lu): filename '%s' matches.", disk, major, minor, filename);
+
+            snprintfz(result, result_size - 1, "%s%s%s", (prefix)?prefix:"", (prefix)?"_":"", de->d_name);
+            found = 1;
+            break;
+        }
     }
     closedir(dir);
 
 
-cleanup:
+failed:
 
     if(!found)
         result[0] = '\0';
@@ -373,10 +408,11 @@ cleanup:
 static inline char *get_disk_name(unsigned long major, unsigned long minor, char *disk) {
     char result[FILENAME_MAX + 1] = "";
 
-    if(!path_to_device_mapper || !*path_to_device_mapper || !get_disk_name_from_path(path_to_device_mapper, result, FILENAME_MAX + 1, major, minor, disk))
-        if(!path_to_device_label || !*path_to_device_label || !get_disk_name_from_path(path_to_device_label, result, FILENAME_MAX + 1, major, minor, disk))
-            if(name_disks_by_id != CONFIG_BOOLEAN_YES || !path_to_device_id || !*path_to_device_id || !get_disk_name_from_path(path_to_device_id, result, FILENAME_MAX + 1, major, minor, disk))
-                strncpy(result, disk, FILENAME_MAX);
+    if(!path_to_device_mapper || !*path_to_device_mapper || !get_disk_name_from_path(path_to_device_mapper, result, FILENAME_MAX + 1, major, minor, disk, NULL, 0))
+        if(!path_to_device_label || !*path_to_device_label || !get_disk_name_from_path(path_to_device_label, result, FILENAME_MAX + 1, major, minor, disk, NULL, 0))
+            if(!path_to_veritas_volume_groups || !*path_to_veritas_volume_groups || !get_disk_name_from_path(path_to_veritas_volume_groups, result, FILENAME_MAX + 1, major, minor, disk, "vx", 2))
+                if(name_disks_by_id != CONFIG_BOOLEAN_YES || !path_to_device_id || !*path_to_device_id || !get_disk_name_from_path(path_to_device_id, result, FILENAME_MAX + 1, major, minor, disk, NULL, 0))
+                    strncpy(result, disk, FILENAME_MAX);
 
     if(!result[0])
         strncpy(result, disk, FILENAME_MAX);
@@ -790,6 +826,9 @@ int do_proc_diskstats(int update_every, usec_t dt) {
         snprintfz(buffer, FILENAME_MAX, "%s/dev/disk/by-id", netdata_configured_host_prefix);
         path_to_device_id = config_get(CONFIG_SECTION_DISKSTATS, "path to /dev/disk/by-id", buffer);
 
+        snprintfz(buffer, FILENAME_MAX, "%s/dev/vx/dsk", netdata_configured_host_prefix);
+        path_to_veritas_volume_groups = config_get(CONFIG_SECTION_DISKSTATS, "path to /dev/vx/dsk", buffer);
+
         name_disks_by_id = config_get_boolean(CONFIG_SECTION_DISKSTATS, "name disks by id", name_disks_by_id);
 
         excluded_disks = simple_pattern_create(