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|
/*
* Copyright © 1999 NCSA
* All rights reserved.
*
* Programmer: Robb Matzke <matzke@llnl.gov>
* Wednesday, October 22, 1997
*
* Purpose: This is the Posix stdio.h I/O subclass of H5Flow.
*
* Notes: Ported to the new H5FD architecture on 10/18/99 - QAK
*
*/
#include "hdf5.h"
#include <assert.h>
#include <stdlib.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef WIN32
#include <windows.h>
#endif
#ifdef MAX
#undef MAX
#endif /* MAX */
#define MAX(X,Y) ((X)>(Y)?(X):(Y))
/* The driver identification number, initialized at runtime */
static hid_t H5FD_STDIO_g = 0;
/* File operations */
typedef enum {
H5FD_STDIO_OP_UNKNOWN=0,
H5FD_STDIO_OP_READ=1,
H5FD_STDIO_OP_WRITE=2,
H5FD_STDIO_OP_SEEK=3
} H5FD_stdio_file_op;
/*
* The description of a file belonging to this driver. The `eoa' and `eof'
* determine the amount of hdf5 address space in use and the high-water mark
* of the file (the current size of the underlying Unix file). The `pos'
* value is used to eliminate file position updates when they would be a
* no-op. Unfortunately we've found systems that use separate file position
* indicators for reading and writing so the lseek can only be eliminated if
* the current operation is the same as the previous operation. When opening
* a file the `eof' will be set to the current file size, `eoa' will be set
* to zero, `pos' will be set to H5F_ADDR_UNDEF (as it is when an error
* occurs), and `op' will be set to H5F_OP_UNKNOWN.
*/
typedef struct H5FD_stdio_t {
H5FD_t pub; /*public stuff, must be first */
FILE * fp; /*the file handle */
haddr_t eoa; /*end of allocated region */
haddr_t eof; /*end of file; current file size*/
haddr_t pos; /*current file I/O position */
H5FD_stdio_file_op op; /*last operation */
unsigned write_access; /* Flag to indicate the file was opened with write access */
#ifndef WIN32
/*
* On most systems the combination of device and i-node number uniquely
* identify a file.
*/
dev_t device; /*file device number */
ino_t inode; /*file i-node number */
#else
/*
* On WIN32 the low-order word of a unique identifier associated with the
* file and the volume serial number uniquely identify a file. This number
* (which, both? -rpm) may change when the system is restarted or when the
* file is opened. After a process opens a file, the identifier is
* constant until the file is closed. An application can use this
* identifier and the volume serial number to determine whether two
* handles refer to the same file.
*/
int fileindexlo;
int fileindexhi;
#endif
} H5FD_stdio_t;
/*
* These macros check for overflow of various quantities. These macros
* assume that file_offset_t is signed and haddr_t and size_t are unsigned.
*
* ADDR_OVERFLOW: Checks whether a file address of type `haddr_t'
* is too large to be represented by the second argument
* of the file seek function.
*
* SIZE_OVERFLOW: Checks whether a buffer size of type `hsize_t' is too
* large to be represented by the `size_t' type.
*
* REGION_OVERFLOW: Checks whether an address and size pair describe data
* which can be addressed entirely by the second
* argument of the file seek function.
*/
#define MAXADDR (((haddr_t)1<<(8*sizeof(long)-1))-1)
#define ADDR_OVERFLOW(A) (HADDR_UNDEF==(A) || ((A) & ~(haddr_t)MAXADDR))
#define SIZE_OVERFLOW(Z) ((Z) & ~(hsize_t)MAXADDR)
#define REGION_OVERFLOW(A,Z) (ADDR_OVERFLOW(A) || SIZE_OVERFLOW(Z) || \
sizeof(long)<sizeof(size_t) || HADDR_UNDEF==(A)+(Z) || (long)((A)+(Z))<(long)(A))
/* Prototypes */
static H5FD_t *H5FD_stdio_open(const char *name, unsigned flags,
hid_t fapl_id, haddr_t maxaddr);
static herr_t H5FD_stdio_close(H5FD_t *lf);
static int H5FD_stdio_cmp(const H5FD_t *_f1, const H5FD_t *_f2);
static haddr_t H5FD_stdio_get_eoa(H5FD_t *_file);
static herr_t H5FD_stdio_set_eoa(H5FD_t *_file, haddr_t addr);
static haddr_t H5FD_stdio_get_eof(H5FD_t *_file);
static herr_t H5FD_stdio_read(H5FD_t *lf, hid_t fapl_id, haddr_t addr,
hsize_t size, void *buf);
static herr_t H5FD_stdio_write(H5FD_t *lf, hid_t fapl_id, haddr_t addr,
hsize_t size, const void *buf);
static herr_t H5FD_stdio_flush(H5FD_t *_file);
static const H5FD_class_t H5FD_stdio_g = {
"stdio", /*name */
MAXADDR, /*maxaddr */
NULL, /*sb_size */
NULL, /*sb_encode */
NULL, /*sb_decode */
0, /*fapl_size */
NULL, /*fapl_get */
NULL, /*fapl_copy */
NULL, /*fapl_free */
0, /*dxpl_size */
NULL, /*dxpl_copy */
NULL, /*dxpl_free */
H5FD_stdio_open, /*open */
H5FD_stdio_close, /*close */
H5FD_stdio_cmp, /*cmp */
NULL, /*alloc */
NULL, /*free */
H5FD_stdio_get_eoa, /*get_eoa */
H5FD_stdio_set_eoa, /*set_eoa */
H5FD_stdio_get_eof, /*get_eof */
H5FD_stdio_read, /*read */
H5FD_stdio_write, /*write */
H5FD_stdio_flush, /*flush */
H5FD_FLMAP_SINGLE, /*fl_map */
};
/*-------------------------------------------------------------------------
* Function: H5FD_stdio_init
*
* Purpose: Initialize this driver by registering the driver with the
* library.
*
* Return: Success: The driver ID for the stdio driver.
*
* Failure: Negative.
*
* Programmer: Robb Matzke
* Thursday, July 29, 1999
*
* Modifications:
* Stolen from the sec2 driver - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
hid_t
H5FD_stdio_init(void)
{
if (H5I_VFL!=H5Iget_type(H5FD_STDIO_g))
H5FD_STDIO_g = H5FDregister(&H5FD_stdio_g);
return(H5FD_STDIO_g);
}
/*-------------------------------------------------------------------------
* Function: H5Pset_fapl_stdio
*
* Purpose: Modify the file access property list to use the H5FD_STDIO
* driver defined in this source file. There are no driver
* specific properties.
*
* Return: Non-negative on success/Negative on failure
*
* Programmer: Robb Matzke
* Thursday, February 19, 1998
*
* Modifications:
* Stolen from the sec2 driver - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
herr_t
H5Pset_fapl_stdio(hid_t fapl_id)
{
if (H5P_FILE_ACCESS!=H5Pget_class(fapl_id))
return -1;
return(H5Pset_driver(fapl_id, H5FD_STDIO, NULL));
}
/*-------------------------------------------------------------------------
* Function: H5FD_stdio_open
*
* Purpose: Create and/or opens a Standard C file as an HDF5 file.
*
* Bugs: H5F_ACC_EXCL has a race condition. (? -QAK)
*
* Errors:
* IO CANTOPENFILE File doesn't exist and CREAT wasn't
* specified.
* IO CANTOPENFILE Fopen failed.
* IO FILEEXISTS File exists but CREAT and EXCL were
* specified.
*
* Return: Success: A pointer to a new file data structure. The
* public fields will be initialized by the
* caller, which is always H5FD_open().
*
* Failure: NULL
*
* Programmer: Robb Matzke
* Wednesday, October 22, 1997
*
* Modifications:
* Ported to VFL/H5FD layer - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
static H5FD_t *
H5FD_stdio_open( const char *name, unsigned flags, hid_t fapl_id,
haddr_t maxaddr)
{
FILE *f = NULL;
unsigned write_access=0; /* File opened with write access? */
H5FD_stdio_t *file=NULL;
static const char *func="H5FD_stdio_open"; /* Function Name for error reporting */
#ifdef WIN32
HFILE filehandle;
struct _BY_HANDLE_FILE_INFORMATION fileinfo;
int results;
#else /* WIN32 */
struct stat sb;
#endif /* WIN32 */
/* Shut compiler up */
fapl_id=fapl_id;
/* Check arguments */
if (!name || !*name) return NULL;
if (0==maxaddr || HADDR_UNDEF==maxaddr) return NULL;
if (ADDR_OVERFLOW(maxaddr)) return NULL;
if (access(name, F_OK) < 0) {
if ((flags & H5F_ACC_CREAT) && (flags & H5F_ACC_RDWR)) {
f = fopen(name, "wb+");
write_access=1; /* Note the write access */
} else {
H5Epush_ret(func, H5E_IO, H5E_CANTOPENFILE,
"file doesn't exist and CREAT wasn't specified", NULL);
}
} else if ((flags & H5F_ACC_CREAT) && (flags & H5F_ACC_EXCL)) {
H5Epush_ret(func, H5E_IO, H5E_FILEEXISTS,
"file exists but CREAT and EXCL were specified", NULL);
} else if (flags & H5F_ACC_RDWR) {
if (flags & H5F_ACC_TRUNC)
f = fopen(name, "wb+");
else
f = fopen(name, "rb+");
write_access=1; /* Note the write access */
} else {
f = fopen(name, "rb");
}
if (!f)
H5Epush_ret(func, H5E_IO, H5E_CANTOPENFILE, "fopen failed", NULL);
/* Build the return value */
if (NULL==(file = calloc(1,sizeof(H5FD_stdio_t)))) {
H5Epush_ret(func, H5E_RESOURCE, H5E_NOSPACE,
"memory allocation failed", NULL);
}
file->fp = f;
file->op = H5FD_STDIO_OP_SEEK;
file->pos = HADDR_UNDEF;
file->write_access=write_access; /* Note the write_access for later */
if (fseek(file->fp, 0, SEEK_END) < 0) {
file->op = H5FD_STDIO_OP_UNKNOWN;
} else {
long x = ftell (file->fp);
assert (x>=0);
file->eof = x;
}
/* The unique key */
#ifdef WIN32
#error "Needs correct fileindexhi & fileindexlo, code below is from sec2 driver"
filehandle = _get_osfhandle(fd);
results = GetFileInformationByHandle(filehandle, &fileinfo);
file->fileindexhi = fileinfo.nFileIndexHigh;
file->fileindexlo = fileinfo.nFileIndexLow;
#else
fstat(fileno(file->fp), &sb);
file->device = sb.st_dev;
file->inode = sb.st_ino;
#endif
return((H5FD_t*)file);
} /* end H5FD_stdio_open() */
/*-------------------------------------------------------------------------
* Function: H5F_stdio_close
*
* Purpose: Closes a file.
*
* Errors:
* IO CLOSEERROR Fclose failed.
*
* Return: Non-negative on success/Negative on failure
*
* Programmer: Robb Matzke
* Wednesday, October 22, 1997
*
* Modifications:
* Ported to VFL/H5FD layer - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
static herr_t
H5FD_stdio_close(H5FD_t *_file)
{
H5FD_stdio_t *file = (H5FD_stdio_t*)_file;
static const char *func="H5FD_stdio_close"; /* Function Name for error reporting */
if (H5FD_stdio_flush(_file)<0)
H5Epush_ret(func, H5E_IO, H5E_WRITEERROR, "flush failed", -1);
if (fclose(file->fp) < 0)
H5Epush_ret(func, H5E_IO, H5E_CLOSEERROR, "fclose failed", -1);
free(file);
return(0);
}
/*-------------------------------------------------------------------------
* Function: H5FD_stdio_cmp
*
* Purpose: Compares two files belonging to this driver using an
* arbitrary (but consistent) ordering.
*
* Return: Success: A value like strcmp()
*
* Failure: never fails (arguments were checked by the
* caller).
*
* Programmer: Robb Matzke
* Thursday, July 29, 1999
*
* Modifications:
* Stolen from the sec2 driver - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
static int
H5FD_stdio_cmp(const H5FD_t *_f1, const H5FD_t *_f2)
{
const H5FD_stdio_t *f1 = (const H5FD_stdio_t*)_f1;
const H5FD_stdio_t *f2 = (const H5FD_stdio_t*)_f2;
#ifdef WIN32
if (f1->fileindexhi < f2->fileindexhi) return -1;
if (f1->fileindexhi > f2->fileindexhi) return 1;
if (f1->fileindexlo < f2->fileindexlo) return -1;
if (f1->fileindexlo > f2->fileindexlo) return 1;
#else
if (f1->device < f2->device) return -1;
if (f1->device > f2->device) return 1;
if (f1->inode < f2->inode) return -1;
if (f1->inode > f2->inode) return 1;
#endif
return 0;
}
/*-------------------------------------------------------------------------
* Function: H5FD_stdio_get_eoa
*
* Purpose: Gets the end-of-address marker for the file. The EOA marker
* is the first address past the last byte allocated in the
* format address space.
*
* Return: Success: The end-of-address marker.
*
* Failure: HADDR_UNDEF
*
* Programmer: Robb Matzke
* Monday, August 2, 1999
*
* Modifications:
* Stolen from the sec2 driver - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
static haddr_t
H5FD_stdio_get_eoa(H5FD_t *_file)
{
H5FD_stdio_t *file = (H5FD_stdio_t*)_file;
return(file->eoa);
}
/*-------------------------------------------------------------------------
* Function: H5FD_stdio_set_eoa
*
* Purpose: Set the end-of-address marker for the file. This function is
* called shortly after an existing HDF5 file is opened in order
* to tell the driver where the end of the HDF5 data is located.
*
* Return: Success: 0
*
* Failure: -1
*
* Programmer: Robb Matzke
* Thursday, July 29, 1999
*
* Modifications:
* Stolen from the sec2 driver - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
static herr_t
H5FD_stdio_set_eoa(H5FD_t *_file, haddr_t addr)
{
H5FD_stdio_t *file = (H5FD_stdio_t*)_file;
file->eoa = addr;
return(0);
}
/*-------------------------------------------------------------------------
* Function: H5FD_stdio_get_eof
*
* Purpose: Returns the end-of-file marker, which is the greater of
* either the Unix end-of-file or the HDF5 end-of-address
* markers.
*
* Return: Success: End of file address, the first address past
* the end of the "file", either the Unix file
* or the HDF5 file.
*
* Failure: HADDR_UNDEF
*
* Programmer: Robb Matzke
* Thursday, July 29, 1999
*
* Modifications:
* Stolen from the sec2 driver - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
static haddr_t
H5FD_stdio_get_eof(H5FD_t *_file)
{
H5FD_stdio_t *file = (H5FD_stdio_t*)_file;
return(MAX(file->eof, file->eoa));
}
/*-------------------------------------------------------------------------
* Function: H5F_stdio_read
*
* Purpose: Reads SIZE bytes beginning at address ADDR in file LF and
* places them in buffer BUF. Reading past the logical or
* physical end of file returns zeros instead of failing.
*
* Errors:
* IO READERROR Fread failed.
* IO SEEKERROR Fseek failed.
*
* Return: Non-negative on success/Negative on failure
*
* Programmer: Robb Matzke
* Wednesday, October 22, 1997
*
* Modifications:
* June 2, 1998 Albert Cheng
* Added xfer_mode argument
*
* Ported to VFL/H5FD layer - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
static herr_t
H5FD_stdio_read(H5FD_t *_file, hid_t dxpl_id, haddr_t addr, hsize_t size,
void *buf/*out*/)
{
size_t n;
H5FD_stdio_t *file = (H5FD_stdio_t*)_file;
static const char *func="H5FD_stdio_read"; /* Function Name for error reporting */
/* Shut compiler up */
dxpl_id=dxpl_id;
/* Check for overflow */
if (HADDR_UNDEF==addr)
H5Epush_ret (func, H5E_IO, H5E_OVERFLOW, "file address overflowed", -1);
if (REGION_OVERFLOW(addr, size))
H5Epush_ret (func, H5E_IO, H5E_OVERFLOW, "file address overflowed", -1);
if (addr+size>file->eoa)
H5Epush_ret (func, H5E_IO, H5E_OVERFLOW, "file address overflowed", -1);
/* Check easy cases */
if (0 == size)
return(0);
if ((uint64_t)addr >= file->eof) {
memset(buf, 0, size);
return(0);
}
/*
* Seek to the correct file position.
*/
if (!(file->op == H5FD_STDIO_OP_READ || file->op==H5FD_STDIO_OP_SEEK) ||
file->pos != addr) {
if (fseek(file->fp, addr, SEEK_SET) < 0) {
file->op = H5FD_STDIO_OP_UNKNOWN;
file->pos = HADDR_UNDEF;
H5Epush_ret(func, H5E_IO, H5E_SEEKERROR, "fseek failed", -1);
}
file->pos = addr;
}
/*
* Read zeros past the logical end of file (physical is handled below)
*/
if ((size_t) addr + size > file->eof) {
size_t nbytes = (size_t) addr + size - file->eof;
memset((unsigned char *)buf + size - nbytes, 0, nbytes);
size -= nbytes;
}
/*
* Read the data. Since we're reading single-byte values, a partial read
* will advance the file position by N. If N is negative or an error
* occurs then the file position is undefined.
*/
n = fread(buf, 1, size, file->fp);
if (n <= 0 && ferror(file->fp)) {
file->op = H5FD_STDIO_OP_UNKNOWN;
file->pos = HADDR_UNDEF;
H5Epush_ret(func, H5E_IO, H5E_READERROR, "fread failed", -1);
} else if (n < size) {
memset((unsigned char *)buf + n, 0, size - n);
}
/*
* Update the file position data.
*/
file->op = H5FD_STDIO_OP_READ;
file->pos = addr+n; /*checked for overflow above*/
return(0);
}
/*-------------------------------------------------------------------------
* Function: H5F_stdio_write
*
* Purpose: Writes SIZE bytes from the beginning of BUF into file LF at
* file address ADDR.
*
* Errors:
* IO SEEKERROR Fseek failed.
* IO WRITEERROR Fwrite failed.
*
* Return: Non-negative on success/Negative on failure
*
* Programmer: Robb Matzke
* Wednesday, October 22, 1997
*
* Modifications:
* June 2, 1998 Albert Cheng
* Added xfer_mode argument
*
* Ported to VFL/H5FD layer - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
static herr_t
H5FD_stdio_write(H5FD_t *_file, hid_t dxpl_id, haddr_t addr,
hsize_t size, const void *buf)
{
H5FD_stdio_t *file = (H5FD_stdio_t*)_file;
static const char *func="H5FD_stdio_write"; /* Function Name for error reporting */
/* Shut compiler up */
dxpl_id=dxpl_id;
/* Check for overflow conditions */
if (HADDR_UNDEF==addr)
H5Epush_ret (func, H5E_IO, H5E_OVERFLOW, "file address overflowed", -1);
if (REGION_OVERFLOW(addr, size))
H5Epush_ret (func, H5E_IO, H5E_OVERFLOW, "file address overflowed", -1);
if (addr+size>file->eoa)
H5Epush_ret (func, H5E_IO, H5E_OVERFLOW, "file address overflowed", -1);
/*
* Seek to the correct file position.
*/
if (!(file->op == H5FD_STDIO_OP_WRITE || file->op==H5FD_STDIO_OP_SEEK) ||
file->pos != addr) {
if (fseek(file->fp, addr, SEEK_SET) < 0) {
file->op = H5FD_STDIO_OP_UNKNOWN;
file->pos = HADDR_UNDEF;
H5Epush_ret(func, H5E_IO, H5E_SEEKERROR, "fseek failed", -1);
}
file->pos = addr;
}
/*
* Write the buffer. On successful return, the file position will be
* advanced by the number of bytes read. Otherwise nobody knows where it
* is.
*/
if (size != fwrite(buf, 1, size, file->fp)) {
file->op = H5FD_STDIO_OP_UNKNOWN;
file->pos = HADDR_UNDEF;
H5Epush_ret(func, H5E_IO, H5E_WRITEERROR, "fwrite failed", -1);
}
/*
* Update seek optimizing data.
*/
file->op = H5FD_STDIO_OP_WRITE;
file->pos = addr + size;
/* Update EOF if necessary */
if (file->pos>file->eof)
file->eof = file->pos;
return(0);
}
/*-------------------------------------------------------------------------
* Function: H5F_stdio_flush
*
* Purpose: Makes sure that all data is on disk.
*
* Errors:
* IO SEEKERROR fseek failed.
* IO WRITEERROR fflush or fwrite failed.
*
* Return: Non-negative on success/Negative on failure
*
* Programmer: Robb Matzke
* Wednesday, October 22, 1997
*
* Modifications:
* Ported to VFL/H5FD layer - QAK, 10/18/99
*
*-------------------------------------------------------------------------
*/
static herr_t
H5FD_stdio_flush(H5FD_t *_file)
{
H5FD_stdio_t *file = (H5FD_stdio_t*)_file;
static const char *func="H5FD_stdio_flush"; /* Function Name for error reporting */
/* Only try to flush the file if we have write access */
if(file->write_access) {
/* Makes sure that the true file size is the same (or larger) than the end-of-address. */
if (file->eoa>file->eof) {
if (fseek(file->fp, file->eoa-1, SEEK_SET)<0)
H5Epush_ret(func, H5E_IO, H5E_SEEKERROR, "fseek failed", -1);
if (fwrite("", 1, 1, file->fp)!=1)
H5Epush_ret(func, H5E_IO, H5E_SEEKERROR, "EOF fwrite failed", -1);
file->eof = file->eoa;
file->pos = file->eoa;
/* fall through to set the IO operation */
}
/*
* What happens to the file position? Is it guaranteed to be the same
* after the fflush() as it was before?
*/
file->op = H5FD_STDIO_OP_UNKNOWN;
/*
* Flush
*/
if (fflush(file->fp) < 0)
H5Epush_ret(func, H5E_IO, H5E_WRITEERROR, "fflush failed", -1);
} /* end if */
else {
/* Double-check for problems */
if (file->eoa>file->eof)
H5Epush_ret(func, H5E_IO, H5E_TRUNCATED, "eoa>eof!", -1);
} /* end else */
return(0);
}
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