WT_LINK added into WORD_TYPES_META

[libucw.git] / lib / fastbuf.h

diff --git a/lib/fastbuf.h b/lib/fastbuf.h
index 3739982c5ad8ecc723d7b51e79dac09d0d44a06e..a370c45be8995155190b5eb61079812a685178e4 100644 (file)
--- a/lib/fastbuf.h
+++ b/lib/fastbuf.h
@@ -1,7 +1,7 @@
 /*
  *     Sherlock Library -- Fast Buffered I/O
  *
 /*
  *     Sherlock Library -- Fast Buffered I/O
  *

- *     (c) 1997--2000 Martin Mares <mj@ucw.cz>
+ *     (c) 1997--2002 Martin Mares <mj@ucw.cz>

  *
  *     This software may be freely distributed and used according to the terms
  *     of the GNU Lesser General Public License.
  *
  *     This software may be freely distributed and used according to the terms
  *     of the GNU Lesser General Public License.


@@ -15,11 +15,13 @@
 #endif
 
 #include <string.h>
 #endif
 
 #include <string.h>

+#include <stdarg.h>

 
 #include "lib/unaligned.h"
 
 /*
 
 #include "lib/unaligned.h"
 
 /*

- *  Generic buffered I/O on a top of buffer swapping functions.
+ *  Generic buffered I/O. You supply hooks to be called for low-level operations
+ *  (swapping of buffers, seeking and closing), we do the rest.

  *
  *  Buffer layout when reading:
  *
  *
  *  Buffer layout when reading:
  *


@@ -35,42 +37,57 @@
  *
  *  When writing:
  *
  *
  *  When writing:
  *

- *  +----------------+---------------------------+
- *  | written data   | free space                |
- *  +----------------+---------------------------+
- *  ^                 ^                           ^
- *  buffer=bstop      bptr                        bufend
+ *  +--------+--------------+--------------------+
+ *  | unused | written data | free space         |
+ *  +--------+--------------+--------------------+
+ *  ^         ^              ^                    ^
+ *  buffer    bstop          bptr                 bufend
+ *
+ *  Dirty tricks:
+ *
+ *    - You can mix reads and writes on the same stream, but you must
+ *     call bflush() in between and remember that the file position
+ *     points after the flushed buffer which is not necessarily the same
+ *     as after the data you've read.
+ *    - The spout/refill hooks can change not only bptr and bstop, but also
+ *     the location of the buffer; fb-mem.c takes advantage of it.

  */
 
 struct fastbuf {
  */
 
 struct fastbuf {

+  byte is_fastbuf[0];                  /* Dummy field for checking of type casts */

   byte *bptr, *bstop;                  /* Access pointers */
   byte *buffer, *bufend;               /* Start and end of the buffer */
   byte *name;                          /* File name for error messages */
   byte *bptr, *bstop;                  /* Access pointers */
   byte *buffer, *bufend;               /* Start and end of the buffer */
   byte *name;                          /* File name for error messages */

-  uns buflen;                          /* Size of the buffer */
-  sh_off_t pos;                                /* Position of buffer start in the file */
-  sh_off_t fdpos;                      /* Current position in the non-buffered file */
-  int fd;                              /* File descriptor, -1 if not a real file */
-  int is_temp_file;                    /* Is a temporary file, delete on close */
-  void *lldata;                                /* Data private to access functions below */
-  void *llpos;                         /* ... continued ... */
+  sh_off_t pos;                                /* Position of bstop in the file */

   int (*refill)(struct fastbuf *);     /* Get a buffer with new data */
   void (*spout)(struct fastbuf *);     /* Write buffer data to the file */
   void (*seek)(struct fastbuf *, sh_off_t, int);  /* Slow path for bseek(), buffer already flushed */
   void (*close)(struct fastbuf *);     /* Close the stream */
   int (*refill)(struct fastbuf *);     /* Get a buffer with new data */
   void (*spout)(struct fastbuf *);     /* Write buffer data to the file */
   void (*seek)(struct fastbuf *, sh_off_t, int);  /* Slow path for bseek(), buffer already flushed */
   void (*close)(struct fastbuf *);     /* Close the stream */

+  int (*config)(struct fastbuf *, uns, int);   /* Configure the stream */

 };
 
 };
 

-/* FastIO on standard files */
+/* FastIO on standard files (specify buffer size 0 to enable mmaping) */

 
 struct fastbuf *bopen(byte *name, uns mode, uns buffer);
 struct fastbuf *bopen_tmp(uns buffer);
 struct fastbuf *bfdopen(int fd, uns buffer);
 
 struct fastbuf *bopen(byte *name, uns mode, uns buffer);
 struct fastbuf *bopen_tmp(uns buffer);
 struct fastbuf *bfdopen(int fd, uns buffer);

-void bbcopy(struct fastbuf *f, struct fastbuf *t, uns l);
+struct fastbuf *bfdopen_shared(int fd, uns buffer);

 
 /* FastIO on in-memory streams */
 
 struct fastbuf *fbmem_create(unsigned blocksize);      /* Create stream and return its writing fastbuf */
 struct fastbuf *fbmem_clone_read(struct fastbuf *);    /* Create reading fastbuf */
 
 
 /* FastIO on in-memory streams */
 
 struct fastbuf *fbmem_create(unsigned blocksize);      /* Create stream and return its writing fastbuf */
 struct fastbuf *fbmem_clone_read(struct fastbuf *);    /* Create reading fastbuf */
 

+/* FastIO on memory mapped files */
+
+struct fastbuf *bopen_mm(byte *name, uns mode);
+
+/* Configuring stream parameters */
+
+int bconfig(struct fastbuf *f, uns type, int data);
+
+#define BCONFIG_IS_TEMP_FILE 0
+

 /* Universal functions working on all fastbuf's */
 
 void bclose(struct fastbuf *f);
 /* Universal functions working on all fastbuf's */
 
 void bclose(struct fastbuf *f);


@@ -80,7 +97,7 @@ void bsetpos(struct fastbuf *f, sh_off_t pos);
 
 static inline sh_off_t btell(struct fastbuf *f)
 {
 
 static inline sh_off_t btell(struct fastbuf *f)
 {

-  return f->pos + (f->bptr - f->buffer);
+  return f->pos + (f->bptr - f->bstop);

 }
 
 int bgetc_slow(struct fastbuf *f);
 }
 
 int bgetc_slow(struct fastbuf *f);


@@ -272,6 +289,21 @@ bputsn(struct fastbuf *f, byte *b)
   bputc(f, '\n');
 }
 
   bputc(f, '\n');
 }
 

+void bbcopy_slow(struct fastbuf *f, struct fastbuf *t, uns l);
+static inline void
+bbcopy(struct fastbuf *f, struct fastbuf *t, uns l)
+{
+  if (f->bptr + l <= f->bstop &&
+      t->bptr + l <= t->bufend)
+    {
+      memcpy(t->bptr, f->bptr, l);
+      t->bptr += l;
+      f->bptr += l;
+    }
+  else
+    bbcopy_slow(f, t, l);
+}
+

 /* I/O on addr_int_t */
 
 #ifdef CPU_64BIT_POINTERS
 /* I/O on addr_int_t */
 
 #ifdef CPU_64BIT_POINTERS


@@ -284,8 +316,39 @@ bputsn(struct fastbuf *f, byte *b)
 
 /* Direct I/O on buffers */
 
 
 /* Direct I/O on buffers */
 

-int bdirect_read(struct fastbuf *f, byte **buf);
-int bdirect_write_prepare(struct fastbuf *f, byte **buf);
-void bdirect_write_commit(struct fastbuf *f, byte *pos);
+static inline uns
+bdirect_read_prepare(struct fastbuf *f, byte **buf)
+{
+  if (f->bptr == f->bstop && !f->refill(f))
+    return 0;
+  *buf = f->bptr;
+  return f->bstop - f->bptr;
+}
+
+static inline void
+bdirect_read_commit(struct fastbuf *f, byte *pos)
+{
+  f->bptr = pos;
+}
+
+static inline uns
+bdirect_write_prepare(struct fastbuf *f, byte **buf)
+{
+  if (f->bptr == f->bufend)
+    f->spout(f);
+  *buf = f->bptr;
+  return f->bufend - f->bptr;
+}
+
+static inline void
+bdirect_write_commit(struct fastbuf *f, byte *pos)
+{
+  f->bptr = pos;
+}
+
+/* Formatted output */
+
+int bprintf(struct fastbuf *b, byte *msg, ...);
+int vbprintf(struct fastbuf *b, byte *msg, va_list args);

 
 #endif
 
 #endif