Merge with git+ssh://git.ucw.cz/projects/sherlock/GIT/sherlock.git

[libucw.git] / lib / fastbuf.h

diff --git a/lib/fastbuf.h b/lib/fastbuf.h
index 55f3d72b3dd884c8f31b2e4cc3cab1ff74c30862..b8d88116fc3eaf0cd494d806ce1c0cb753a5a760 100644 (file)
--- a/lib/fastbuf.h
+++ b/lib/fastbuf.h
@@ -63,7 +63,7 @@ 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 */
+  char *name;                          /* File name for error messages */
   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 */
@@ -73,8 +73,37 @@ struct fastbuf {
   int can_overwrite_buffer;            /* Can the buffer be altered? (see discussion above) 0=never, 1=temporarily, 2=permanently */
 };
 
+/* FastIO on files with run-time parametrization */
+
+enum fb_type {                         /* Which back-end you want to use */
+  FB_STD,                              /* Standard buffered I/O */
+  FB_DIRECT,                           /* Direct I/O bypassing system caches (see fb-direct.c for description) */
+  FB_MMAP                              /* Memory mapped files */
+};
+
+struct fb_params {
+  enum fb_type type;
+  uns buffer_size;
+  /* FB_STD only */
+  uns keep_back_buf;
+  /* FB_DIRECT only */
+  uns read_ahead;                      
+  uns write_back;
+  struct asio_queue *asio;
+};
+
+struct cf_section;
+extern struct cf_section fbpar_cf;
+extern struct fb_params fbpar_def;
+
+struct fastbuf *bopen_file(const char *name, int mode, struct fb_params *params);      /* Use params==NULL for defaults */
+struct fastbuf *bopen_file_try(const char *name, int mode, struct fb_params *params);
+struct fastbuf *bopen_tmp_file(struct fb_params *params);
+struct fastbuf *bopen_fd(int fd, struct fb_params *params);
+
 /* FastIO on standard files (specify buffer size 0 to enable mmaping) */
 
+struct fastbuf *bfdopen_internal(int fd, const char *name, uns buflen);
 struct fastbuf *bopen(const char *name, uns mode, uns buflen);
 struct fastbuf *bopen_try(const char *name, uns mode, uns buflen);
 struct fastbuf *bopen_tmp(uns buflen);
@@ -85,15 +114,19 @@ void bfilesync(struct fastbuf *b);
 #define TEMP_FILE_NAME_LEN 256
 void temp_file_name(char *name);
 
+/* Internal functions of some file back-ends */
+
+struct fastbuf *bfmmopen_internal(int fd, const char *name, uns mode);
+
+extern uns fbdir_cheat;
+struct asio_queue;
+struct fastbuf *fbdir_open_fd_internal(int fd, const char *name, struct asio_queue *io_queue, uns buffer_size, uns read_ahead, uns write_back);
+
 /* FastIO on in-memory streams */
 
 struct fastbuf *fbmem_create(uns 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(const char *name, uns mode);
-
 /* FastI on file descriptors with limit */
 
 struct fastbuf *bopen_limited_fd(int fd, uns bufsize, uns limit);
@@ -114,6 +147,20 @@ 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 on memory pools */
+
+struct mempool;
+struct fbpool {
+  struct fastbuf fb;
+  struct mempool *mp;
+};
+
+void fbpool_init(struct fbpool *fb);   /* Initialize a new fastbuf */
+void fbpool_start(struct fbpool *fb, struct mempool *mp, uns init_size);
+                                       /* Start a new continuous block and prepare for writing (see mp_start()) */
+void *fbpool_end(struct fbpool *fb);   /* Close the block and return its address (see mp_end()).
+                                          The length can be determined with mp_size(mp, ptr). */
+
 /* FastO with atomic writes for multi-threaded programs */
 
 struct fb_atomic {
@@ -136,9 +183,12 @@ fbatomic_commit(struct fastbuf *b)
 
 /* Configuring stream parameters */
 
-int bconfig(struct fastbuf *f, uns type, int data);
+enum bconfig_type {
+  BCONFIG_IS_TEMP_FILE,
+  BCONFIG_KEEP_BACK_BUF,
+};
 
-#define BCONFIG_IS_TEMP_FILE 0
+int bconfig(struct fastbuf *f, uns type, int data);
 
 /* Universal functions working on all fastbuf's */