Added a direct I/O fastbuf backend.

[libucw.git] / lib / fastbuf.h

diff --git a/lib/fastbuf.h b/lib/fastbuf.h
index 6dbacce5dcebf52c73b5fdeac47cfd8511ceda23..c5e1deb860f8610ed5cbb5eba03f6723e78c9cd7 100644 (file)
--- a/lib/fastbuf.h
+++ b/lib/fastbuf.h
@@ -19,7 +19,6 @@
 #include <alloca.h>
 
 #include "lib/unaligned.h"
-#include "lib/bbuf.h"
 
 /*
  *  Generic buffered I/O. You supply hooks to be called for low-level operations
@@ -98,6 +97,14 @@ struct fastbuf *fbmem_clone_read(struct fastbuf *);  /* Create reading fastbuf */
 
 struct fastbuf *bopen_mm(byte *name, uns mode);
 
+/* FastIO on files opened with O_DIRECT (see fb-direct.c for description) */
+
+struct asio_queue;
+struct fastbuf *fbdir_open(byte *name, uns mode, struct asio_queue *io_queue);
+struct fastbuf *fbdir_open_try(byte *name, uns mode, struct asio_queue *io_queue);
+struct fastbuf *fbdir_open_fd(int fd, struct asio_queue *io_queue);
+struct fastbuf *fbdir_open_tmp(int fd, struct asio_queue *io_queue);
+
 /* FastI on file descriptors with limit */
 
 struct fastbuf *bopen_limited_fd(int fd, uns bufsize, uns limit);
@@ -118,6 +125,26 @@ struct fastbuf *fbgrow_create(unsigned basic_size);
 void fbgrow_reset(struct fastbuf *b);                  /* Reset stream and prepare for writing */
 void fbgrow_rewind(struct fastbuf *b);                 /* Prepare for reading */
 
+/* FastO with atomic writes for multi-threaded programs */
+
+struct fb_atomic {
+  struct fastbuf fb;
+  struct fb_atomic_file *af;
+  byte *expected_max_bptr;
+  uns slack_size;
+};
+#define FB_ATOMIC(f) ((struct fb_atomic *)(f)->is_fastbuf)
+
+struct fastbuf *fbatomic_open(byte *name, struct fastbuf *master, uns bufsize, int record_len);
+void fbatomic_internal_write(struct fastbuf *b);
+
+static inline void
+fbatomic_commit(struct fastbuf *b)
+{
+  if (b->bptr >= ((struct fb_atomic *)b)->expected_max_bptr)
+    fbatomic_internal_write(b);
+}
+
 /* Configuring stream parameters */
 
 int bconfig(struct fastbuf *f, uns type, int data);
@@ -322,7 +349,8 @@ int bgets_nodie(struct fastbuf *f, byte *b, uns l);
 byte *bgets0(struct fastbuf *f, byte *b, uns l);
 
 struct mempool;
-uns bgets_bb(struct fastbuf *f, bb_t *b, uns limit);
+struct bb_t;
+uns bgets_bb(struct fastbuf *f, struct bb_t *b, uns limit);
 byte *bgets_mp(struct fastbuf *f, struct mempool *mp);
 
 struct bgets_stk_struct {