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-rw-r--r--debian/htdig/htdig-3.2.0b6/db/mp_trickle.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/debian/htdig/htdig-3.2.0b6/db/mp_trickle.c b/debian/htdig/htdig-3.2.0b6/db/mp_trickle.c
new file mode 100644
index 00000000..61e45f1f
--- /dev/null
+++ b/debian/htdig/htdig-3.2.0b6/db/mp_trickle.c
@@ -0,0 +1,136 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997, 1998, 1999
+ * Sleepycat Software. All rights reserved.
+ */
+#include "db_config.h"
+
+#ifndef lint
+static const char sccsid[] = "@(#)mp_trickle.c 11.3 (Sleepycat) 9/16/99";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+
+#include <errno.h>
+#include <stdlib.h>
+#endif
+
+#include "db_int.h"
+#include "db_shash.h"
+#include "mp.h"
+
+static int CDB___memp_trick __P((DB_ENV *, int, int, int *));
+
+/*
+ * CDB_memp_trickle --
+ * Keep a specified percentage of the buffers clean.
+ */
+int
+CDB_memp_trickle(dbenv, pct, nwrotep)
+ DB_ENV *dbenv;
+ int pct, *nwrotep;
+{
+ DB_MPOOL *dbmp;
+ MPOOL *mp;
+ u_int32_t i;
+ int ret;
+
+ PANIC_CHECK(dbenv);
+ ENV_REQUIRES_CONFIG(dbenv, dbenv->mp_handle, DB_INIT_MPOOL);
+
+ dbmp = dbenv->mp_handle;
+ mp = dbmp->reginfo.primary;
+
+ if (nwrotep != NULL)
+ *nwrotep = 0;
+
+ if (pct < 1 || pct > 100)
+ return (EINVAL);
+
+ R_LOCK(dbenv, &dbmp->reginfo);
+
+ /* Loop through the caches... */
+ for (ret = 0, i = 0; i < mp->nc_reg; ++i)
+ if ((ret = CDB___memp_trick(dbenv, i, pct, nwrotep)) != 0)
+ break;
+
+ R_UNLOCK(dbenv, &dbmp->reginfo);
+ return (ret);
+}
+
+/*
+ * CDB___memp_trick --
+ * Trickle a single cache.
+ */
+static int
+CDB___memp_trick(dbenv, ncache, pct, nwrotep)
+ DB_ENV *dbenv;
+ int ncache, pct, *nwrotep;
+{
+ BH *bhp;
+ DB_MPOOL *dbmp;
+ MCACHE *mc;
+ MPOOLFILE *mfp;
+ db_pgno_t pgno;
+ u_long total;
+ int ret, wrote;
+
+ dbmp = dbenv->mp_handle;
+ mc = dbmp->c_reginfo[ncache].primary;
+
+ /*
+ * If there are sufficient clean buffers, or no buffers or no dirty
+ * buffers, we're done.
+ *
+ * XXX
+ * Using st_page_clean and st_page_dirty is our only choice at the
+ * moment, but it's not as correct as we might like in the presence
+ * of pools with more than one buffer size, as a free 512-byte buffer
+ * isn't the same as a free 8K buffer.
+ */
+loop: total = mc->stat.st_page_clean + mc->stat.st_page_dirty;
+ if (total == 0 || mc->stat.st_page_dirty == 0 ||
+ (mc->stat.st_page_clean * 100) / total >= (u_long)pct)
+ return (0);
+
+ /* Loop until we write a buffer. */
+ for (bhp = SH_TAILQ_FIRST(&mc->bhq, __bh);
+ bhp != NULL; bhp = SH_TAILQ_NEXT(bhp, q, __bh)) {
+ if (bhp->ref != 0 ||
+ !F_ISSET(bhp, BH_DIRTY) || F_ISSET(bhp, BH_LOCKED))
+ continue;
+
+ mfp = R_ADDR(&dbmp->reginfo, bhp->mf_offset);
+
+ /*
+ * We can't write to temporary files -- see the comment in
+ * mp_bh.c:CDB___memp_bhwrite().
+ */
+ if (F_ISSET(mfp, MP_TEMP))
+ continue;
+
+ pgno = bhp->pgno;
+ if ((ret = CDB___memp_bhwrite(dbmp, mfp, bhp, NULL, &wrote)) != 0)
+ return (ret);
+
+ /*
+ * Any process syncing the shared memory buffer pool had better
+ * be able to write to any underlying file. Be understanding,
+ * but firm, on this point.
+ */
+ if (!wrote) {
+ CDB___db_err(dbenv, "%s: unable to flush page: %lu",
+ CDB___memp_fns(dbmp, mfp), (u_long)pgno);
+ return (EPERM);
+ }
+
+ ++mc->stat.st_page_trickle;
+ if (nwrotep != NULL)
+ ++*nwrotep;
+ goto loop;
+ }
+
+ return (0);
+}