Refactor large parts of the program.

The new design assures revDNS/WHOIS queries will be done exactly once, no matter how many requests the Schachtmeister gets.
This commit also adds cache timeouts.

1 files changed, 49 insertions, 27 deletions

diff --git a/src/shared.h b/src/shared.h
index a615f83..77c9d3f 100644
--- a/src/shared.h
+++ b/src/shared.h
@@ -47,49 +47,71 @@ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 
 extern int server_sockfd;
 
+uint64_t get_time(void);
+
+#define TIME_SECOND (1000000000llu)
+#define TIME_MINUTE (60 * TIME_SECOND)
+#define TIME_HOUR   (60 * TIME_MINUTE)
+
+// shared
+
+typedef struct job_s job_t;
+
+// database.c
+
+enum {
+	DB_INVALID,
+	DB_IN_PROGRESS,
+	DB_VALID
+};
+
+typedef struct {
+	int state;
+	uint64_t exp_time;
+	char *data;
+} db_entry_field;
+
+typedef struct {
+	uint32_t ipv4;
+
+	db_entry_field revdns, whois;
+
+	bool cached_result_valid;
+	int cached_result;
+
+	job_t *waiting_jobs;
+
+	eli_header ht_chain;
+	pthread_mutex_t mutex;
+} db_entry;
+
+db_entry *db_find(uint32_t ipv4);
+void db_destroy(void);
+
 // worker.c
 
 typedef enum {
-	JOB_TEST,
 	JOB_REVDNS,
-	JOB_WHOIS
+	JOB_WHOIS,
+	JOB_REPLY,
 } job_type_t;
 
-typedef struct job_s job_t;
 struct job_s {
 	job_type_t type;
 
-	uint32_t query;
-	struct sockaddr_in reply_to;
+	db_entry *entry;
+	struct sockaddr_in ret_addr; // for JOB_REPLY
+	uint32_t ipv4; // for other jobs
 
-	eli_header list, dep_list;
-	job_t *parent, *deps;
-	size_t num_deps, deps_done;
-	pthread_mutex_t mutex;
+	eli_header queue_list, waiting_list;
 };
 
-job_t *job_create(void);
+job_t *job_create(job_type_t type, db_entry *entry);
+void job_destroy(job_t *job);
 void job_enqueue(job_t *job);
 void job_quit(void);
 void *worker_main(void *unused);
 
-// cache.c
-
-typedef struct {
-	uint32_t ipv4;
-
-	char *revdns;
-	uint64_t revdns_exptime; // FIXME: implement this already
-	char *whois;
-	uint64_t whois_exptime;
-
-	eli_header ht_list;
-	pthread_mutex_t mutex;
-} cache_entry_t;
-
-cache_entry_t *cache_find(uint32_t ipv4);
-void cache_destroy(void);
-
 // lexer.c
 
 typedef struct {