diff options
Diffstat (limited to 'lib/device/dev-cache.c')
| -rw-r--r-- | lib/device/dev-cache.c | 254 |
1 files changed, 165 insertions, 89 deletions
diff --git a/lib/device/dev-cache.c b/lib/device/dev-cache.c index 4e6ed3ec..7b4d6a79 100644 --- a/lib/device/dev-cache.c +++ b/lib/device/dev-cache.c @@ -9,6 +9,8 @@ #include "pool.h" #include "hash.h" #include "list.h" +#include "lvm-types.h" +#include "btree.h" #include "dbg_malloc.h" #include <stdlib.h> @@ -24,7 +26,7 @@ */ struct dev_iter { - struct hash_node *current; + struct btree_iter *current; struct dev_filter *filter; }; @@ -35,7 +37,8 @@ struct dir_list { static struct { struct pool *mem; - struct hash_table *devices; + struct hash_table *names; + struct btree *devices; int has_scanned; struct list_head dirs; @@ -46,10 +49,91 @@ static struct { #define _alloc(x) pool_alloc(_cache.mem, (x)) #define _free(x) pool_free(_cache.mem, (x)) -static int _dir_scan(const char *dir); +static int _insert(const char *path, int rec); + +static struct device *_create_dev(const char *path, dev_t d) +{ + struct device *dev; + char *name = pool_strdup(_cache.mem, path); + + if (!name) { + stack; + return NULL; + } + + if (!(dev = _alloc(sizeof(*dev)))) { + stack; + goto bad; + } + + dev->name = name; + INIT_LIST_HEAD(&dev->aliases); + dev->dev = d; + return dev; + + bad: + _free(name); + return NULL; +} + +static int _add_alias(struct device *dev, const char *path) +{ + struct str_list *sl = _alloc(sizeof(*sl)); + + if (!sl) { + stack; + return 0; + } + + if (!(sl->str = pool_strdup(_cache.mem, path))) { + stack; + return 0; + } + + list_add(&sl->list, &dev->aliases); + return 1; +} + +/* + * Either creates a new dev, or adds an alias to + * an existing dev. + */ +static int _insert_dev(const char *path, dev_t d) +{ + struct device *dev; + + /* is this device already registered ? */ + if ((dev = (struct device *) btree_lookup(_cache.devices, d))) { + if (!_add_alias(dev, path)) { + log_err("Couldn't add alias to dir cache."); + return 0; + } + + } else { + /* create new device */ + if (!(dev = _create_dev(path, d))) { + stack; + return 0; + } + + if (!(btree_insert(_cache.devices, d, dev))) { + log_err("Couldn't insert device into binary tree."); + _free(dev); + return 0; + } + } + + /* insert the name/alias */ + if (!(hash_insert(_cache.names, path, dev))) { + log_err("Couldn't insert device into hash table."); + return 0; + } + + return 1; +} /* - * return a new path for the destination of the path. + * return a new path for the destination of the link. */ static char *_follow_link(const char *path, struct stat *info) { @@ -70,6 +154,16 @@ static char *_follow_link(const char *path, struct stat *info) return pool_strdup(_cache.mem, buffer); } +static char *_join(const char *dir, const char *name) +{ + int len = strlen(dir) + strlen(name) + 2; + char *r = dbg_malloc(len); + if (r) + snprintf(r, len, "%s/%s", dir, name); + + return r; +} + /* * Get rid of extra slashes in the path string. */ @@ -92,113 +186,83 @@ static void _collapse_slashes(char *str) *str = *ptr; } -static struct device *_create_dev(const char *path, struct stat *info) +static int _insert_dir(const char *dir) { - struct device *dev; - char *name = pool_strdup(_cache.mem, path); + int n, dirent_count, r = 1; + struct dirent **dirent; + char *path; - if (!name) { - stack; - return NULL; - } + dirent_count = scandir(dir, &dirent, NULL, alphasort); + if (dirent_count > 0) { + for (n = 0; n < dirent_count; n++) { + if (dirent[n]->d_name[0] == '.') { + free(dirent[n]); + continue; + } - _collapse_slashes(name); + if (!(path = _join(dir, dirent[n]->d_name))) { + stack; + return 0; + } - if (!(dev = _alloc(sizeof(*dev)))) { - stack; - goto bad; - } + _collapse_slashes(path); + r &= _insert(path, 1); + dbg_free(path); - dev->name = name; - dev->dev = info->st_rdev; - return dev; + free(dirent[n]); + } + free(dirent); + } - bad: - _free(name); - return NULL; + return r; } -static int _insert(const char *path, int recurse) +static int _insert(const char *path, int rec) { struct stat info; - struct device *dev; - - /* If entry already exists, replace it */ - if ((dev = (struct device *)hash_lookup(_cache.devices, path))) { - log_debug("dev-cache: removing %s", path); - hash_remove(_cache.devices, path); - } + char *actual_path; + int r = 0; if (stat(path, &info) < 0) { log_sys_very_verbose("stat", path); return 0; } - if (S_ISDIR(info.st_mode)) { - if (recurse) - return _dir_scan(path); - - return 0; - } - + /* follow symlinks if neccessary. */ if (S_ISLNK(info.st_mode)) { log_debug("%s: Following symbolic link", path); - if (!(path = _follow_link(path, &info))) { + if (!(actual_path = _follow_link(path, &info))) { stack; return 0; } - } - if (!S_ISBLK(info.st_mode)) { - log_debug("%s: Not a block device", path); - return 0; - } + if (stat(actual_path, &info) < 0) { + log_sys_very_verbose("stat", actual_path); + return 0; + } - if (!(dev = _create_dev(path, &info))) { - log_debug("%s: Creation of device cache entry failed!", path); - return 0; + dbg_free(actual_path); } - log_debug("dev-cache: adding %s", path); - hash_insert(_cache.devices, path, dev); - - return 1; -} - -static char *_join(const char *dir, const char *name) -{ - int len = strlen(dir) + strlen(name) + 2; - char *r = dbg_malloc(len); - if (r) - snprintf(r, len, "%s/%s", dir, name); - - return r; -} - -static int _dir_scan(const char *dir) -{ - int n, dirent_count; - struct dirent **dirent; - char *path; - - dirent_count = scandir(dir, &dirent, NULL, alphasort); - if (dirent_count > 0) { - for (n = 0; n < dirent_count; n++) { - if (dirent[n]->d_name[0] == '.') { - free(dirent[n]); - continue; - } + if (S_ISDIR(info.st_mode)) { /* add a directory */ + if (rec) + r = _insert_dir(path); - if ((path = _join(dir, dirent[n]->d_name))) - _insert(path, 1); + } else { /* add a device */ + if (!S_ISBLK(info.st_mode)) { + log_debug("%s: Not a block device", path); + return 0; + } - dbg_free(path); - free(dirent[n]); + if (!_insert_dev(path, info.st_rdev)) { + stack; + return 0; } - free(dirent); + + r = 1; } - return 1; + return r; } static void _full_scan(void) @@ -210,7 +274,7 @@ static void _full_scan(void) list_for_each(tmp, &_cache.dirs) { struct dir_list *dl = list_entry(tmp, struct dir_list, list); - _dir_scan(dl->dir); + _insert_dir(dl->dir); } _cache.has_scanned = 1; @@ -218,27 +282,39 @@ static void _full_scan(void) int dev_cache_init(void) { + _cache.names = NULL; + if (!(_cache.mem = pool_create(10 * 1024))) { stack; return 0; } - if (!(_cache.devices = hash_create(128))) { + if (!(_cache.names = hash_create(128))) { stack; pool_destroy(_cache.mem); _cache.mem = 0; return 0; } + if (!(_cache.devices = btree_create(_cache.mem))) { + log_err("Couldn't create binary tree for dev-cache."); + goto bad; + } + INIT_LIST_HEAD(&_cache.dirs); return 1; + + bad: + dev_cache_exit(); + return 0; } void dev_cache_exit(void) { pool_destroy(_cache.mem); - hash_destroy(_cache.devices); + if (_cache.names) + hash_destroy(_cache.names); } int dev_cache_add_dir(const char *path) @@ -267,11 +343,11 @@ int dev_cache_add_dir(const char *path) struct device *dev_cache_get(const char *name, struct dev_filter *f) { - struct device *d = (struct device *) hash_lookup(_cache.devices, name); + struct device *d = (struct device *) hash_lookup(_cache.names, name); if (!d) { _insert(name, 0); - d = (struct device *) hash_lookup(_cache.devices, name); + d = (struct device *) hash_lookup(_cache.names, name); } return (d && (!f || f->passes_filter(f, d))) ? d : NULL; @@ -285,7 +361,7 @@ struct dev_iter *dev_iter_create(struct dev_filter *f) return NULL; _full_scan(); - di->current = hash_get_first(_cache.devices); + di->current = btree_first(_cache.devices); di->filter = f; return di; @@ -298,8 +374,8 @@ void dev_iter_destroy(struct dev_iter *iter) static inline struct device *_iter_next(struct dev_iter *iter) { - struct device *d = hash_get_data(_cache.devices, iter->current); - iter->current = hash_get_next(_cache.devices, iter->current); + struct device *d = btree_get_data(iter->current); + iter->current = btree_next(iter->current); return d; } |