liblastlog2: wait on busy SQLite connections

Avoiding 'SQL error: database is locked' when lastlog2 writes lastlog2
databese.

Addresses: https://github.com/util-linux/util-linux/issues/4157
Signed-off-by: WanBingjiang <wanbingjiang@webray.com.cn>

diff --git a/liblastlog2/src/lastlog2.c b/liblastlog2/src/lastlog2.c
index 058e0d5aafc25046af8865c8a8591d525b8832b6..def17e31197fd39d2227cdffa01724998eb88705 100644 (file)
--- a/liblastlog2/src/lastlog2.c
+++ b/liblastlog2/src/lastlog2.c
@@ -39,6 +39,23 @@
 #include "lastlog2P.h"
 #include "strutils.h"
 
+#define LASTLOG2_BUSY_TIMEOUT 3000
+
+static int
+set_busy_timeout(sqlite3 *db, const char *path, char **error)
+{
+       int ret = 0;
+
+       if (sqlite3_busy_timeout(db, LASTLOG2_BUSY_TIMEOUT) != SQLITE_OK) {
+               ret = -1;
+               if (error && asprintf(error, "Cannot set busy timeout (%s): %s",
+                                    path, sqlite3_errmsg(db)) < 0)
+                       ret = -ENOMEM;
+       }
+
+       return ret;
+}
+
 /* Sets the ll2 context/environment. */
 /* Returns the context or NULL if an error has happened. */
 extern struct ll2_context * ll2_new_context(const char *db_path)
@@ -87,6 +104,13 @@ open_database_ro(struct ll2_context *context, sqlite3 **db, char **error)
                                ret = -ENOMEM;
 
                sqlite3_close(*db);
+               return ret;
+       }
+
+       ret = set_busy_timeout(*db, path, error);
+       if (ret != 0) {
+               sqlite3_close(*db);
+               return ret;
        }
 
        return ret;
@@ -110,6 +134,13 @@ open_database_rw(struct ll2_context *context,  sqlite3 **db, char **error)
                                ret = -ENOMEM;
 
                sqlite3_close(*db);
+               return ret;
+       }
+
+       ret = set_busy_timeout(*db, path, error);
+       if (ret != 0) {
+               sqlite3_close(*db);
+               return ret;
        }
 
        return ret;