X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;ds=sidebyside;f=lib%2Ffastbuf.h;h=4e3bc5ca2afb721ed19635ed603dbf0d1796ac16;hb=bc09f812bc50c357125f471fced2828046dc1486;hp=475f833560def6ea7b4b8ce18e2e0849a6d3b4d6;hpb=bb483446d9c8a0227887aa2b3e7494a973d06593;p=libucw.git

diff --git a/lib/fastbuf.h b/lib/fastbuf.h
index 475f8335..4e3bc5ca 100644
--- 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 */
@@ -77,14 +77,17 @@ struct fastbuf {
 
 enum fb_type {				/* Which back-end you want to use */
   FB_STD,				/* Standard buffered I/O */
-  FB_DIRECT,				/* Direct I/O bypassing system caches */
+  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;
-  uns read_ahead;			/* The next three fields are used for FB_DIRECT files */
+  /* FB_STD only */
+  uns keep_back_buf;
+  /* FB_DIRECT only */
+  uns read_ahead;			
   uns write_back;
   struct asio_queue *asio;
 };
@@ -93,44 +96,36 @@ struct cf_section;
 extern struct cf_section fbpar_cf;
 extern struct fb_params fbpar_def;
 
-struct fastbuf *bopen_file(byte *name, int mode, struct fb_params *params);		/* Use params==NULL for defaults */
-struct fastbuf *bopen_file_try(byte *name, int mode, struct fb_params *params);
+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) */
+/* FastIO on standard files */
 
-struct fastbuf *bfdopen_internal(int fd, byte *name, uns buflen);
-struct fastbuf *bopen(byte *name, uns mode, uns buflen);
-struct fastbuf *bopen_try(byte *name, uns mode, uns buflen);
+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);
 struct fastbuf *bfdopen(int fd, uns buflen);
 struct fastbuf *bfdopen_shared(int fd, uns buflen);
 void bfilesync(struct fastbuf *b);
 
 #define TEMP_FILE_NAME_LEN 256
-void temp_file_name(byte *name);
+void temp_file_name(char *name);
 
-/* 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 */
+/* Internal functions of some file back-ends */
 
-/* FastIO on memory mapped files */
-
-struct fastbuf *bfmmopen_internal(int fd, byte *name, uns mode);
-struct fastbuf *bopen_mm(byte *name, uns mode);
-
-/* FastIO on files opened with O_DIRECT (see fb-direct.c for description) */
+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, byte *name, struct asio_queue *io_queue, uns buffer_size, uns read_ahead, uns write_back);
-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(struct asio_queue *io_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 */
 
 /* FastI on file descriptors with limit */
 
@@ -152,6 +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 {
@@ -162,7 +171,7 @@ struct fb_atomic {
 };
 #define FB_ATOMIC(f) ((struct fb_atomic *)(f)->is_fastbuf)
 
-struct fastbuf *fbatomic_open(byte *name, struct fastbuf *master, uns bufsize, int record_len);
+struct fastbuf *fbatomic_open(const char *name, struct fastbuf *master, uns bufsize, int record_len);
 void fbatomic_internal_write(struct fastbuf *b);
 
 static inline void
@@ -174,9 +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 */
 
@@ -255,8 +267,8 @@ static inline uns breadb(struct fastbuf *f, void *b, uns l)
     return bread_slow(f, b, l, 1);
 }
 
-void bwrite_slow(struct fastbuf *f, void *b, uns l);
-static inline void bwrite(struct fastbuf *f, void *b, uns l)
+void bwrite_slow(struct fastbuf *f, const void *b, uns l);
+static inline void bwrite(struct fastbuf *f, const void *b, uns l)
 {
   if (bavailw(f) >= l)
     {
@@ -267,14 +279,29 @@ static inline void bwrite(struct fastbuf *f, void *b, uns l)
     bwrite_slow(f, b, l);
 }
 
-byte *bgets(struct fastbuf *f, byte *b, uns l);	/* Non-std */
-int bgets_nodie(struct fastbuf *f, byte *b, uns l);
-byte *bgets0(struct fastbuf *f, byte *b, uns l);
+/*
+ *  Functions for reading of strings:
+ *
+ *     bgets()		reads a line, strip the trailing '\n' and return a pointer
+ *			to the terminating 0 or NULL on EOF. Dies if the line is too long.
+ *     bgets0()		does the same for 0-terminated strings.
+ *     bgets_nodie()	a variant of bgets() which returns either the length of the
+ *     			string (excluding the terminator) or -1 if the line does not fit
+ *     			in the buffer. In such cases, it returns after reading exactly `l'
+ *     			bytes of input.
+ *     bgets_bb()	a variant of bgets() which allocates the string in a growing buffer
+ *     bgets_mp()	the same, but in a mempool
+ *     bgets_stk()	the same, but on the stack by alloca()
+ */
+
+char *bgets(struct fastbuf *f, char *b, uns l);
+char *bgets0(struct fastbuf *f, char *b, uns l);
+int bgets_nodie(struct fastbuf *f, char *b, uns l);
 
 struct mempool;
 struct bb_t;
 uns bgets_bb(struct fastbuf *f, struct bb_t *b, uns limit);
-byte *bgets_mp(struct fastbuf *f, struct mempool *mp);
+char *bgets_mp(struct fastbuf *f, struct mempool *mp);
 
 struct bgets_stk_struct {
   struct fastbuf *f;
@@ -286,19 +313,19 @@ void bgets_stk_step(struct bgets_stk_struct *s);
 #define bgets_stk(fb) ({ struct bgets_stk_struct _s; _s.f = (fb); for (bgets_stk_init(&_s); _s.cur_len; _s.cur_buf = alloca(_s.cur_len), bgets_stk_step(&_s)); _s.cur_buf; })
 
 static inline void
-bputs(struct fastbuf *f, byte *b)
+bputs(struct fastbuf *f, const char *b)
 {
   bwrite(f, b, strlen(b));
 }
 
 static inline void
-bputs0(struct fastbuf *f, byte *b)
+bputs0(struct fastbuf *f, const char *b)
 {
   bwrite(f, b, strlen(b)+1);
 }
 
 static inline void
-bputsn(struct fastbuf *f, byte *b)
+bputsn(struct fastbuf *f, const char *b)
 {
   bputs(f, b);
   bputc(f, '\n');
@@ -374,7 +401,7 @@ bdirect_write_commit(struct fastbuf *f, byte *pos)
 
 /* Formatted output */
 
-int bprintf(struct fastbuf *b, char *msg, ...) FORMAT_CHECK(printf,2,3);
-int vbprintf(struct fastbuf *b, char *msg, va_list args);
+int bprintf(struct fastbuf *b, const char *msg, ...) FORMAT_CHECK(printf,2,3);
+int vbprintf(struct fastbuf *b, const char *msg, va_list args);
 
 #endif