hdf5/src/H5Fprivate.h

/****************************************************************************
 * NCSA HDF                                                                 *
 * Software Development Group                                               *
 * National Center for Supercomputing Applications                          *
 * University of Illinois at Urbana-Champaign                               *
 * 605 E. Springfield, Champaign IL 61820                                   *
 *                                                                          *
 * For conditions of distribution and use, see the accompanying             *
 * hdf/COPYING file.                                                        *
 *                                                                          *
 ****************************************************************************/

/* $Id$ */

/*
 * This file contains macros & information for file access
 */

#ifndef _H5Fprivate_H
#define _H5Fprivate_H
#include <H5Fpublic.h>

/* This is a near top-level header! Try not to include much! */
#include <H5private.h>

/*
 * Feature: Define this constant to be non-zero if you want to enable code
 *	    that minimizes the number of calls to lseek().  This has a huge
 *	    performance benefit on some systems.  Set this constant to zero
 *	    on the compiler command line to disable that optimization.
 */
#ifndef H5F_OPT_SEEK
#  define H5F_OPT_SEEK 1
#endif

/* Maximum size of boot-block buffer */
#define H5F_BOOTBLOCK_SIZE  1024

/* Define the HDF5 file signature */
#define H5F_SIGNATURE     "\211HDF\r\n\032\n"
#define H5F_SIGNATURE_LEN 8

/* size of size_t and off_t as they exist on disk */
#define H5F_SIZEOF_OFFSET(F) ((F)->shared->file_create_parms.offset_size)
#define H5F_SIZEOF_SIZE(F)	((F)->shared->file_create_parms.length_size)

/*
 * File open flags.
 */
#define H5F_ACC_WRITE	0x0001	/* Open file for read/write access	*/
#define H5F_ACC_CREAT	0x0002	/* Create non-existing files		*/
#define H5F_ACC_EXCL	0x0004	/* Fail if file exists			*/
#define H5F_ACC_TRUNC	0x0008	/* Truncate existing file		*/


/*
 * Encode and decode macros for file meta-data.
 * Currently, all file meta-data is little-endian.
 */

/* For non-little-endian platforms, encode each byte by itself */
#ifdef WORDS_BIGENDIAN
#  define INT16ENCODE(p, i) {						      \
   *(p) = (uint8)( (uintn)(i)       & 0xff); (p)++;			      \
   *(p) = (uint8)(((uintn)(i) >> 8) & 0xff); (p)++;			      \
}

#  define UINT16ENCODE(p, i) {						      \
   *(p) = (uint8)(        (i)       & 0xff); (p)++;			      \
   *(p) = (uint8)(((uintn)(i) >> 8) & 0xff); (p)++;			      \
}

#  define INT32ENCODE(p, i) {						      \
   *(p) = (uint8)( (uint32)(i)        & 0xff); (p)++;			      \
   *(p) = (uint8)(((uint32)(i) >>  8) & 0xff); (p)++;			      \
   *(p) = (uint8)(((uint32)(i) >> 16) & 0xff); (p)++;			      \
   *(p) = (uint8)(((uint32)(i) >> 24) & 0xff); (p)++;			      \
}

#  define UINT32ENCODE(p, i) {						      \
   *(p) = (uint8)( (i)        & 0xff); (p)++;				      \
   *(p) = (uint8)(((i) >>  8) & 0xff); (p)++;				      \
   *(p) = (uint8)(((i) >> 16) & 0xff); (p)++;				      \
   *(p) = (uint8)(((i) >> 24) & 0xff); (p)++;				      \
}

#  define INT64ENCODE(p, n) {						      \
   int64 _n = (n);							      \
   intn _i;								      \
   uint8 *_p = (uint8*)(p);						      \
   for (_i=0; _i<sizeof(int64); _i++, _n>>=8) {				      \
      *_p++ = _n & 0xff;						      \
   }									      \
   for (/*void*/; _i<8; _i++) {						      \
      *_p++ = (n)<0 ? 0xff : 0;						      \
   }									      \
   (p) = (uint8*)(p)+8;							      \
}

#  define UINT64ENCODE(p, n) {						      \
   uint64 _n = (n);							      \
   intn _i;								      \
   uint8 *_p = (uint8*)(p);						      \
   for (_i=0; _i<sizeof(uint64); _i++, _n>>=8) {			      \
      *_p++ = _n & 0xff;						      \
   }									      \
   for (/*void*/; _i<8; _i++) {						      \
      *_p++ = 0;							      \
   }									      \
   (p) = (uint8*)(p)+8;							      \
}

#  define INT16DECODE(p, i) {						      \
   (i)  = (int16)((*(p) & 0xff));      (p)++;				      \
   (i) |= (int16)((*(p) & 0xff) << 8); (p)++;				      \
}

#  define UINT16DECODE(p, i) {						      \
   (i)  = (uint16) (*(p) & 0xff);       (p)++;				      \
   (i) |= (uint16)((*(p) & 0xff) << 8); (p)++;				      \
}

#  define INT32DECODE(p, i) {						      \
   (i)  = (        *(p) & 0xff);        (p)++;				      \
   (i) |= ((int32)(*(p) & 0xff) <<  8); (p)++;				      \
   (i) |= ((int32)(*(p) & 0xff) << 16); (p)++;				      \
   (i) |= ((int32)(*(p) & 0xff) << 24); (p)++;				      \
}

#  define UINT32DECODE(p, i) {						      \
   (i)  =  (uint32)(*(p) & 0xff);        (p)++;				      \
   (i) |= ((uint32)(*(p) & 0xff) <<  8); (p)++;				      \
   (i) |= ((uint32)(*(p) & 0xff) << 16); (p)++;				      \
   (i) |= ((uint32)(*(p) & 0xff) << 24); (p)++;				      \
}

#  define INT64DECODE(p, n) {						      \
   /* WE DON'T CHECK FOR OVERFLOW! */					      \
   int64 _n = 0;							      \
   intn _i;								      \
   uint8 *_p = (uint8*)(p)+8;						      \
   for (_i=0; _i<sizeof(int64); _i++, _n<<=8) {				      \
      _n |= *(--_p);							      \
   }									      \
   (p) = (uint8*)(p)+8;							      \
}

#  define UINT64DECODE(p, n) {						      \
   /* WE DON'T CHECK FOR OVERFLOW! */					      \
   uint64 _n = 0;							      \
   intn _i;								      \
   uint8 *_p = (uint8*)(p)+8;						      \
   for (_i=0; _i<sizeof(uint64); _i++, _n<<=8) {			      \
      _n |= *(--_p);							      \
   }									      \
   (p) = (uint8*)(p)+8;							      \
}

#else
   /* For little-endian platforms, make the compiler do the work */
#  define INT16ENCODE(p, i)  { *((int16 *)(p)) = (int16)(i); (p)+=2; }
#  define UINT16ENCODE(p, i) { *((uint16 *)(p)) = (uint16)(i); (p)+=2; }
#  define INT32ENCODE(p, i)  { *((int32 *)(p)) = (int32)(i); (p)+=4; }
#  define UINT32ENCODE(p, i) { *((uint32 *)(p)) = (uint32)(i); (p)+=4; }

#  define INT64ENCODE(p, i)  {						      \
   *((int64 *)(p)) = (int64)(i);					      \
   (p) += sizeof(int64);						      \
   if (4==sizeof(int64)) {						      \
      *(p)++ = (i)<0?0xff:0x00;						      \
      *(p)++ = (i)<0?0xff:0x00;						      \
      *(p)++ = (i)<0?0xff:0x00;						      \
      *(p)++ = (i)<0?0xff:0x00;						      \
   }									      \
}

#  define UINT64ENCODE(p, i) {						      \
   *((uint64 *)(p)) = (uint64)(i);					      \
   (p) += sizeof(uint64);						      \
   if (4==sizeof(uint64)) {						      \
      *(p)++ = 0x00;							      \
      *(p)++ = 0x00;							      \
      *(p)++ = 0x00;							      \
      *(p)++ = 0x00;							      \
   }									      \
}

#  define INT16DECODE(p, i)  { (i) = (int16)(*(const int16 *)(p)); (p)+=2; }
#  define UINT16DECODE(p, i) { (i) = (uint16)(*(const uint16 *)(p)); (p)+=2; }
#  define INT32DECODE(p, i)  { (i) = (int32)(*(const int32 *)(p)); (p)+=4; }
#  define UINT32DECODE(p, i) { (i) = (uint32)(*(const uint32 *)(p)); (p)+=4; }
#  define INT64DECODE(p, i)  { (i) = (int64)(*(const int64 *)(p)); (p)+=8; }
#  define UINT64DECODE(p, i) { (i) = (uint64)(*(const uint64 *)(p)); (p)+=8; }

#endif

#define NBYTEENCODE(d, s, n) {   HDmemcpy(d,s,n); p+=n }

/* Note! the NBYTEDECODE macro is backwards from the memcpy() routine, */
/*      in the spirit of the other DECODE macros */
#define NBYTEDECODE(s, d, n) {   HDmemcpy(d,s,n); p+=n }

/*
 * File-creation template information structure
 */
typedef struct {
   uintn userblock_size;	/* Size of the file user block in bytes */
   uintn sym_leaf_k;		/* 1/2 rank for symbol table leaf nodes */
   uintn btree_k[8];		/* 1/2 rank for btree internal nodes 	*/
   uint8 offset_size;          	/* Number of bytes for offsets 		*/
   uint8 length_size;          	/* Number of bytes for lengths 		*/
   uint8 bootblock_ver;        	/* Version # of the bootblock 		*/
   uint8 smallobject_ver;      	/* Version # of the small-object heap 	*/
   uint8 freespace_ver;        	/* Version # of the free-space information */
   uint8 objectdir_ver;        	/* Version # of the object directory format */
   uint8 sharedheader_ver;     	/* Version # of the shared header format */
} file_create_temp_t;

/*
 * These things make a file unique.
 */
typedef struct H5F_search_t {
   dev_t	dev;		/* Device number containing file	*/
   ino_t	ino;		/* Unique file number on device		*/
} H5F_search_t;

/* For determining what the last file operation was */
typedef enum {
   H5F_OP_UNKNOWN,	   	/* Don't know what the last operation was */
   H5F_OP_SEEK,          	/* Last operation was a seek		*/
   H5F_OP_WRITE,         	/* Last operation was a write		*/
   H5F_OP_READ           	/* Last operation was a read		*/
} H5F_fileop_t;

/*
 * Define the low-level file interface.
 */
typedef struct H5F_low_class_t {
   struct H5F_low_t *(*open)(const char*, uintn);
   herr_t (*close)(struct H5F_low_t*);
   herr_t (*read)(struct H5F_low_t*, haddr_t, size_t, uint8*);
   herr_t (*write)(struct H5F_low_t*, haddr_t, size_t, const uint8*);
   herr_t (*flush)(struct H5F_low_t*);
   size_t (*size)(struct H5F_low_t*);
} H5F_low_class_t;

typedef struct H5F_low_t {
   const H5F_low_class_t *type;	/* What type of file is this?		*/
   union {

      /* Posix section 2 I/O */
      struct {
	 int		fd;	/* The unix file descriptor		*/
	 H5F_fileop_t	op;	/* Previous file operation		*/
	 haddr_t	cur;	/* Current file position		*/
      } sec2;

      /* Posix stdio */
      struct {
	 FILE		*f;	/* Posix stdio file			*/
	 H5F_fileop_t	op;	/* Previous file operation		*/
	 haddr_t	cur;	/* Current file position		*/
      } stdio;
      
   } u;
} H5F_low_t;

/* What types of low-level files are there? */
#ifndef H5F_LOW_DFLT
#  define H5F_LOW_DFLT	H5F_LOW_STDIO		/* The default type	*/
#endif
extern const H5F_low_class_t H5F_LOW_SEC2[];	/* Posix section 2	*/
extern const H5F_low_class_t H5F_LOW_STDIO[];	/* Posix stdio 		*/

   
/*
 * Define the structure to store the file information for HDF5 files. One of
 * these structures is allocated per file, not per H5Fopen().
 */
typedef struct H5F_file_t {
   H5F_search_t	key;		/* The key for looking up files		*/
   uintn	flags;         	/* Access Permissions for file		*/
   H5F_low_t	*file_handle;	/* Lower level file handle for I/O	*/
   uintn	nrefs;        	/* Ref count for times file is opened 	*/
   uint32 	consist_flags; 	/* File Consistency Flags 		*/
   haddr_t 	smallobj_off;  	/* Offset of small-obj heap within the file */
   haddr_t 	freespace_off; 	/* Offset of free-space info within the file */
   size_t	logical_len;   	/* Logical length of file 		*/
   struct H5AC_t *cache; 	/* The object cache 			*/
   file_create_temp_t file_create_parms; /* File-creation template 	*/
#ifdef LATER
   file_access_temp_t file_access_parms; /* File-access template	*/
#endif
   struct H5G_entry_t *root_sym; /* Root symbol table entry		*/
   uintn nshadows;		/* Size of shadow hash table		*/
   struct H5G_hash_t **shadow;	/* The shadow hash table		*/
} H5F_file_t;

/*
 * This is the top-level file descriptor.  One of these structures is
 * allocated every time H5Fopen() is called although they may contain
 * pointers to shared H5F_file_t structs.
 */
typedef struct H5F_t {
   uintn	intent;		/* The flags passed to H5F_open()	*/
   char		*name;		/* Name used to open file		*/
   H5F_file_t	*shared;	/* The shared file info			*/
   struct H5G_cwgstk_t *cwg_stack; /* CWG stack for push/pop functions	*/
} H5F_t;




#ifdef NOT_YET
#define H5F_encode_offset(f,p,o) (H5F_SIZEOF_OFFSET(f)==4 ? UINT32ENCODE(p,o) \
    : H5F_SIZEOF_OFFSET(f)==8 ? UINT64ENCODE(p,o) \
    : H5F_SIZEOF_OFFSET(f)==2 ? UINT16ENCODE(p,o) \
    : H5FPencode_unusual_offset(f,&(p),(uint8 *)&(o)))
#else /* NOT_YET */
#define H5F_encode_offset(f,p,o) switch(H5F_SIZEOF_OFFSET(f)) { case 4: UINT32ENCODE(p,o); break;\
    case 8: UINT64ENCODE(p,o); break;\
    case 2: UINT16ENCODE(p,o); break;}
#endif /* NOT_YET */

#define H5F_decode_offset(f,p,o)					      \
   switch (H5F_SIZEOF_OFFSET (f)) {					      \
   case 4:								      \
      UINT32DECODE (p, o);						      \
      break;								      \
   case 8:								      \
      UINT64DECODE (p, o);						      \
      break;								      \
   case 2:								      \
      UINT16DECODE (p, o);						      \
      break;								      \
   }

#ifdef NOT_YET
#define H5F_encode_length(f,p,l) (H5F_SIZEOF_SIZE(f)==4 ? UINT32ENCODE(p,l) \
    : H5F_SIZEOF_SIZE(f)==8 ? UINT64ENCODE(p,l) \
    : H5F_SIZEOF_SIZE(f)==2 ? UINT16ENCODE(p,l) : H5FPencode_unusual_length(f,&(p),(uint8 *)&(l)))
#else
#define H5F_encode_length(f,p,l)					      \
   switch(H5F_SIZEOF_SIZE(f)) {						      \
   case 4: UINT32ENCODE(p,l); break;					      \
   case 8: UINT64ENCODE(p,l); break;					      \
   case 2: UINT16ENCODE(p,l); break;					      \
}
#endif

#define H5F_decode_length(f,p,l)					      \
   switch(H5F_SIZEOF_SIZE(f)) {						      \
   case 4: UINT32DECODE(p,l); break;					      \
   case 8: UINT64DECODE(p,l); break;					      \
   case 2: UINT16DECODE(p,l); break;					      \
}

struct H5O_istore_t; /*forward decl for prototype arguments*/

/* Private functions, not part of the publicly documented API */
void H5F_encode_length_unusual(const H5F_t *f, uint8 **p, uint8 *l);
void H5F_encode_offset_unusual(const H5F_t *f, uint8 **p, uint8 *o);
H5F_t *H5F_open (const H5F_low_class_t *type, const char *name, uintn flags,
		 const file_create_temp_t *create_parms);
herr_t H5F_close (H5F_t *f);
herr_t H5F_debug (H5F_t *f, haddr_t addr, FILE *stream, intn indent,
		  intn fwidth);

/* Functions that operate on indexed storage */
herr_t H5F_istore_new (H5F_t *f, struct H5O_istore_t *istore,
		       uintn ndims, const size_t alignment[]);
herr_t H5F_istore_read (H5F_t *f, const struct H5O_istore_t *mesg,
			const size_t offset[], const size_t size[],
			void *buf);
herr_t H5F_istore_write (H5F_t *f, const struct H5O_istore_t *mesg,
			 const size_t offset[], const size_t size[],
			 void *buf);

/* Functions that operate on contiguous storage wrt boot block */
herr_t H5F_block_read (H5F_t *f, haddr_t addr, size_t size, void *buf);
herr_t H5F_block_write (H5F_t *f, haddr_t addr, size_t size, void *buf);

/* Functions that operate directly on low-level files */
H5F_low_t *H5F_low_open (const H5F_low_class_t *type, const char *name,
			 uintn flags);
H5F_low_t *H5F_low_close (H5F_low_t *lf);
size_t H5F_low_size (H5F_low_t *lf);
herr_t H5F_low_read (H5F_low_t *lf, haddr_t addr, size_t size, uint8 *buf);
herr_t H5F_low_write (H5F_low_t *lf, haddr_t addr, size_t size,
		      const uint8 *buf);

#endif