From: Masatake YAMATO <yamato@redhat.com>
Date: Fri, 7 May 2021 16:50:20 +0000 (+0900)
Subject: lsfd: introduce name_manager
X-Git-Tag: v2.38-rc1~144^2~142
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=5179d5282499319ca4e2888ffe425b2b17869491;p=thirdparty%2Futil-linux.git

lsfd: introduce name_manager

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
---

diff --git a/misc-utils/lsfd.c b/misc-utils/lsfd.c
index 17a426f9d5..cc6adc78ff 100644
--- a/misc-utils/lsfd.c
+++ b/misc-utils/lsfd.c
@@ -1003,6 +1003,76 @@ int main(int argc, char *argv[])
 	return 0;
 }
 
+struct name_manager {
+	struct idcache *cache;
+	pthread_rwlock_t rwlock;
+	unsigned long next_id;
+};
+
+struct name_manager *new_name_manager(void)
+{
+	struct name_manager *nm = xcalloc(1, sizeof(struct name_manager));
+	nm->cache = new_idcache();
+	if (!nm->cache)
+		err(EXIT_FAILURE, _("failed to allocate an idcache"));
+
+	pthread_rwlock_init(&nm->rwlock, NULL);
+	nm->next_id = 1;	/* 0 is never issued as id. */
+	return nm;
+}
+
+void free_name_manager(struct name_manager *nm)
+{
+	free_idcache(nm->cache);
+	free(nm);
+}
+
+const char *get_name(struct name_manager *nm, unsigned long id)
+{
+	struct identry *e;
+
+	pthread_rwlock_rdlock(&nm->rwlock);
+	e = get_id(nm->cache, id);
+	pthread_rwlock_unlock(&nm->rwlock);
+
+	return e? e->name: NULL;
+}
+
+unsigned long add_name(struct name_manager *nm, const char *name)
+{
+	struct identry *e = NULL, *tmp;
+
+	pthread_rwlock_rdlock(&nm->rwlock);
+	for (tmp = nm->cache->ent; tmp; tmp = tmp->next) {
+		if (strcmp(tmp->name, name) == 0) {
+			e = tmp;
+			break;
+		}
+	}
+	pthread_rwlock_unlock(&nm->rwlock);
+	if (e)
+		return e->id;
+
+	pthread_rwlock_wrlock(&nm->rwlock);
+	for (tmp = nm->cache->ent; tmp; tmp = tmp->next) {
+		if (strcmp(tmp->name, name) == 0) {
+			e = tmp;
+			break;
+		}
+	}
+
+	if (!e) {
+		e = xmalloc(sizeof(struct identry));
+		e->name = xstrdup(name);
+		e->id = nm->next_id++;
+		e->next = nm->cache->ent;
+		nm->cache->ent = e;
+	}
+	pthread_rwlock_unlock(&nm->rwlock);
+
+	return e->id;
+}
+
 DIR *opendirf(const char *format, ...)
 {
 	va_list ap;
diff --git a/misc-utils/lsfd.h b/misc-utils/lsfd.h
index 7862973adb..c800e38f59 100644
--- a/misc-utils/lsfd.h
+++ b/misc-utils/lsfd.h
@@ -148,4 +148,14 @@ struct file *make_sock(const struct file_class *class,
 struct file *make_unkn(const struct file_class *class,
 		       struct stat *sb, const char *name, int fd);
 
+/*
+ * Name managing
+ */
+struct name_manager;
+
+struct name_manager *new_name_manager(void);
+void free_name_manager(struct name_manager *nm);
+const char *get_name(struct name_manager *nm, unsigned long id);
+unsigned long add_name(struct name_manager *nm, const char *name);
+
 #endif /* UTIL_LINUX_LSFD_H */