From 0ca1ebba6125984fbb004231713b9893705e8859 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Wed, 30 Aug 2017 14:21:18 -0700
Subject: [PATCH] ircd::db: Fix valid condition bugs and minor cleanup.

---
 include/ircd/db/database.h | 7 ++++---
 include/ircd/db/row.h      | 3 +++
 ircd/db.cc                 | 7 +++++--
 3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/include/ircd/db/database.h b/include/ircd/db/database.h
index de7b60e63..e8ba6a887 100644
--- a/include/ircd/db/database.h
+++ b/include/ircd/db/database.h
@@ -49,7 +49,7 @@ namespace ircd::db
 }
 
 struct ircd::db::database
-:std::enable_shared_from_this<struct database>
+:std::enable_shared_from_this<database>
 {
 	struct descriptor;
 	struct options;
@@ -60,7 +60,7 @@ struct ircd::db::database
 	struct snapshot;
 	struct comparator;
 	struct column;
-	using description = std::initializer_list<struct descriptor>;
+	using description = std::initializer_list<descriptor>;
 
 	// central collection of open databases for iteration (non-owning)
 	static std::map<string_view, database *> dbs;
@@ -113,7 +113,6 @@ namespace ircd::db
 	std::shared_ptr<const database::column> shared_from(const database::column &);
 	std::shared_ptr<database::column> shared_from(database::column &);
 	const std::string &name(const database::column &);
-	uint64_t sequence(const database::snapshot &);   // Sequence of a snapshot
 	uint32_t id(const database::column &);
 	void drop(database::column &);                   // Request to erase column from db
 }
@@ -188,4 +187,6 @@ struct ircd::db::database::snapshot
 	explicit snapshot(database &);
 	snapshot() = default;
 	~snapshot() noexcept;
+
+	friend uint64_t sequence(const snapshot &);  // Sequence of a snapshot
 };
diff --git a/include/ircd/db/row.h b/include/ircd/db/row.h
index 14fd02d07..3c2625d3b 100644
--- a/include/ircd/db/row.h
+++ b/include/ircd/db/row.h
@@ -38,6 +38,9 @@ namespace ircd::db
 // will all return the same index value across the whole `row`. To get the names
 // of the columns themselves to build ex. the key name of a JSON key-value pair,
 // use `cell::col()`, which will be different for each `cell` across the `row`.
+//
+// The db::row::iterator iterates over the cells in a row; to iterate over
+// multiple rows use the db::cursor
 struct ircd::db::row
 {
 	struct delta;
diff --git a/ircd/db.cc b/ircd/db.cc
index 023ab5093..9da91b6d9 100644
--- a/ircd/db.cc
+++ b/ircd/db.cc
@@ -1397,7 +1397,7 @@ ircd::db::cell::compare_exchange(string_view &expected,
 ircd::db::cell &
 ircd::db::cell::operator=(const string_view &s)
 {
-	write(c, index, s);
+	write(c, key(), s);
 	return *this;
 }
 
@@ -1458,7 +1458,7 @@ bool
 ircd::db::cell::valid()
 const
 {
-	return it && valid_equal(*it, index);
+	return it && (index.empty() || valid_equal(*it, index));
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -2935,4 +2935,7 @@ ircd::db::value_required(const op &op)
 		case op::SINGLE_DELETE:
 			return false;
 	}
+
+	assert(0);
+	return false;
 }