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Diffstat (limited to 'src/H5FDsec2.c')
| -rw-r--r-- | src/H5FDsec2.c | 585 |
1 files changed, 585 insertions, 0 deletions
diff --git a/src/H5FDsec2.c b/src/H5FDsec2.c new file mode 100644 index 0000000..b383b92 --- /dev/null +++ b/src/H5FDsec2.c @@ -0,0 +1,585 @@ +/* + * Copyright © 1999 NCSA + * All rights reserved. + * + * Programmer: Robb Matzke <matzke@llnl.gov> + * Thursday, July 29, 1999 + * + * Purpose: The POSIX unbuffered file driver using only the HDF5 public + * API and with a few optimizations: the lseek() call is made + * only when the current file position is unknown or needs to be + * changed based on previous I/O through this driver (don't mix + * I/O from this driver with I/O from other parts of the + * application to the same file). + */ +#include <assert.h> +#include <errno.h> +#include <fcntl.h> +#include <hdf5.h> +#include <stdlib.h> +#include <sys/stat.h> +#include <unistd.h> + + +#undef MAX +#define MAX(X,Y) ((X)>(Y)?(X):(Y)) + +/* The driver identification number, initialized at runtime */ +static hid_t H5FD_SEC2_g = 0; + +/* File operations */ +#define OP_UNKNOWN 0 +#define OP_READ 1 +#define OP_WRITE 2 + +/* + * 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_sec2_t { + H5FD_t pub; /*public stuff, must be first */ + int fd; /*the unix file */ + haddr_t eoa; /*end of allocated region */ + haddr_t eof; /*end of file; current file size*/ + haddr_t pos; /*current file I/O position */ + int op; /*last operation */ +#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_sec2_t; + +/* + * This driver supports systems that have the lseek64() function by defining + * some macros here so we don't have to have conditional compilations later + * throughout the code. + * + * file_offset_t: The datatype for file offsets, the second argument of + * the lseek() or lseek64() call. + * + * file_seek: The function which adjusts the current file position, + * either lseek() or lseek64(). + */ +#ifdef HAVE_LSEEK64 +# define file_offset_t off64_t +# define file_seek lseek64 +#else +# define file_offset_t off_t +# define file_seek lseek +#endif + +/* + * 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(file_offset_t)-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(file_offset_t)<sizeof(size_t) || \ + HADDR_UNDEF==(A)+(Z) || \ + (file_offset_t)((A)+(Z))<(file_offset_t)(A)) + +/* Prototypes */ +static H5FD_t *H5FD_sec2_open(const char *name, unsigned flags, hid_t fapl_id, + haddr_t maxaddr); +static herr_t H5FD_sec2_close(H5FD_t *_file); +static int H5FD_sec2_cmp(const H5FD_t *_f1, const H5FD_t *_f2); +static haddr_t H5FD_sec2_get_eoa(H5FD_t *_file); +static herr_t H5FD_sec2_set_eoa(H5FD_t *_file, haddr_t addr); +static haddr_t H5FD_sec2_get_eof(H5FD_t *_file); +static herr_t H5FD_sec2_read(H5FD_t *_file, hid_t fapl_id, haddr_t addr, + hsize_t size, void *buf); +static herr_t H5FD_sec2_write(H5FD_t *_file, hid_t fapl_id, haddr_t addr, + hsize_t size, const void *buf); +static herr_t H5FD_sec2_flush(H5FD_t *_file); + +static const H5FD_class_t H5FD_sec2_g = { + "sec2", /*name */ + MAXADDR, /*maxaddr */ + 0, /*fapl_size */ + NULL, /*fapl_copy */ + NULL, /*fapl_free */ + 0, /*dxpl_size */ + NULL, /*dxpl_copy */ + NULL, /*dxpl_free */ + H5FD_sec2_open, /*open */ + H5FD_sec2_close, /*close */ + H5FD_sec2_cmp, /*cmp */ + NULL, /*alloc */ + NULL, /*free */ + H5FD_sec2_get_eoa, /*get_eoa */ + H5FD_sec2_set_eoa, /*set_eoa */ + H5FD_sec2_get_eof, /*get_eof */ + H5FD_sec2_read, /*read */ + H5FD_sec2_write, /*write */ + H5FD_sec2_flush, /*flush */ + H5FD_FLMAP_SINGLE, /*fl_map */ +}; + + +/*------------------------------------------------------------------------- + * Function: H5FD_sec2_init + * + * Purpose: Initialize this driver by registering the driver with the + * library. + * + * Return: Success: The driver ID for the sec2 driver. + * + * Failure: Negative. + * + * Programmer: Robb Matzke + * Thursday, July 29, 1999 + * + * Modifications: + * + *------------------------------------------------------------------------- + */ +hid_t +H5FD_sec2_init(void) +{ + if (!H5FD_SEC2_g) { + H5FD_SEC2_g = H5FDregister(&H5FD_sec2_g); + } + return H5FD_SEC2_g; +} + + +/*------------------------------------------------------------------------- + * Function: H5Pset_fapl_sec2 + * + * Purpose: Modify the file access property list to use the H5FD_SEC2 + * 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: + * + *------------------------------------------------------------------------- + */ +herr_t +H5Pset_fapl_sec2(hid_t fapl_id) +{ + /*NO TRACE*/ + if (H5P_FILE_ACCESS!=H5Pget_class(fapl_id)) return -1; + return H5Pset_driver(fapl_id, H5FD_SEC2, NULL); +} + + +/*------------------------------------------------------------------------- + * Function: H5FD_sec2_open + * + * Purpose: Create and/or opens a Unix file as an HDF5 file. + * + * 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 + * Thursday, July 29, 1999 + * + * Modifications: + * + *------------------------------------------------------------------------- + */ +static H5FD_t * +H5FD_sec2_open(const char *name, unsigned flags, hid_t fapl_id/*unused*/, + haddr_t maxaddr) +{ + unsigned o_flags; + int fd; + struct stat sb; + H5FD_sec2_t *file=NULL; + + /* Check arguments */ + if (!name || !*name) return NULL; + if (0==maxaddr || HADDR_UNDEF==maxaddr) return NULL; + if (ADDR_OVERFLOW(maxaddr)) return NULL; + + /* Build the open flags */ + o_flags = (H5F_ACC_RDWR & flags) ? O_RDWR : O_RDONLY; + if (H5F_ACC_TRUNC & flags) o_flags |= O_TRUNC; + if (H5F_ACC_CREAT & flags) o_flags |= O_CREAT; + if (H5F_ACC_EXCL & flags) o_flags |= O_EXCL; + + /* Open the file */ + if ((fd=open(name, o_flags, 0666))<0) return NULL; + if (fstat(fd, &sb)<0) { + close(fd); + return NULL; + } + + /* Create the new file struct */ + file = calloc(1, sizeof(H5FD_sec2_t)); + file->fd = fd; + file->eof = sb.st_size; + file->pos = HADDR_UNDEF; + file->op = OP_UNKNOWN; + file->device = sb.st_dev; + file->inode = sb.st_ino; + + return (H5FD_t*)file; +} + + +/*------------------------------------------------------------------------- + * Function: H5FD_sec2_close + * + * Purpose: Closes a Unix file. + * + * Return: Success: 0 + * + * Failure: -1, file not closed. + * + * Programmer: Robb Matzke + * Thursday, July 29, 1999 + * + * Modifications: + * + *------------------------------------------------------------------------- + */ +static herr_t +H5FD_sec2_close(H5FD_t *_file) +{ + H5FD_sec2_t *file = (H5FD_sec2_t*)_file; + + if (H5FD_sec2_flush(_file)<0) return -1; + if (close(file->fd)<0) return -1; + free(file); + return 0; +} + + +/*------------------------------------------------------------------------- + * Function: H5FD_sec2_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: + * + *------------------------------------------------------------------------- + */ +static int +H5FD_sec2_cmp(const H5FD_t *_f1, const H5FD_t *_f2) +{ + const H5FD_sec2_t *f1 = (const H5FD_sec2_t*)_f1; + const H5FD_sec2_t *f2 = (const H5FD_sec2_t*)_f2; + + 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; + + return 0; +} + + +/*------------------------------------------------------------------------- + * Function: H5FD_sec2_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: + * + *------------------------------------------------------------------------- + */ +static haddr_t +H5FD_sec2_get_eoa(H5FD_t *_file) +{ + H5FD_sec2_t *file = (H5FD_sec2_t*)_file; + return file->eoa; +} + + +/*------------------------------------------------------------------------- + * Function: H5FD_sec2_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: + * + *------------------------------------------------------------------------- + */ +static herr_t +H5FD_sec2_set_eoa(H5FD_t *_file, haddr_t addr) +{ + H5FD_sec2_t *file = (H5FD_sec2_t*)_file; + file->eoa = addr; + return 0; +} + + +/*------------------------------------------------------------------------- + * Function: H5FD_sec2_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: + * + *------------------------------------------------------------------------- + */ +static haddr_t +H5FD_sec2_get_eof(H5FD_t *_file) +{ + H5FD_sec2_t *file = (H5FD_sec2_t*)_file; + return MAX(file->eof, file->eoa); +} + + +/*------------------------------------------------------------------------- + * Function: H5FD_sec2_read + * + * Purpose: Reads SIZE bytes of data from FILE beginning at address ADDR + * into buffer BUF according to data transfer properties in + * DXPL_ID. + * + * Return: Success: Zero. Result is stored in caller-supplied + * buffer BUF. + * + * Failure: -1, Contents of buffer BUF are undefined. + * + * Programmer: Robb Matzke + * Thursday, July 29, 1999 + * + * Modifications: + * + *------------------------------------------------------------------------- + */ +static herr_t +H5FD_sec2_read(H5FD_t *_file, hid_t dxpl_id/*unused*/, haddr_t addr, + hsize_t size, void *buf/*out*/) +{ + H5FD_sec2_t *file = (H5FD_sec2_t*)_file; + ssize_t nbytes; + + assert(file && file->pub.cls); + assert(buf); + + /* Check for overflow conditions */ + if (HADDR_UNDEF==addr) return -1; + if (REGION_OVERFLOW(addr, size)) return -1; + if (addr+size>file->eoa) return -1; + + /* Seek to the correct location */ + if ((addr!=file->pos || OP_READ!=file->op) && + file_seek(file->fd, (file_offset_t)addr, SEEK_SET)<0) { + file->pos = HADDR_UNDEF; + file->op = OP_UNKNOWN; + return -1; + } + + /* + * Read data, being careful of interrupted system calls, partial results, + * and the end of the file. + */ + while (size>0) { + do nbytes = read(file->fd, buf, size); + while (-1==nbytes && EINTR==errno); + if (-1==nbytes) { + /* error */ + file->pos = HADDR_UNDEF; + file->op = OP_UNKNOWN; + return -1; + } + if (0==nbytes) { + /* end of file but not end of format address space */ + memset(buf, 0, size); + size = 0; + } + assert(nbytes>=0); + assert((hsize_t)nbytes<=size); + size -= (hsize_t)nbytes; + addr += (haddr_t)nbytes; + buf = (char*)buf + nbytes; + } + + /* Update current position */ + file->pos = addr; + file->op = OP_READ; + return 0; +} + + +/*------------------------------------------------------------------------- + * Function: H5FD_sec2_write + * + * Purpose: Writes SIZE bytes of data to FILE beginning at address ADDR + * from buffer BUF according to data transfer properties in + * DXPL_ID. + * + * Return: Success: Zero + * + * Failure: -1 + * + * Programmer: Robb Matzke + * Thursday, July 29, 1999 + * + * Modifications: + * + *------------------------------------------------------------------------- + */ +static herr_t +H5FD_sec2_write(H5FD_t *_file, hid_t dxpl_id/*unused*/, haddr_t addr, + hsize_t size, const void *buf) +{ + H5FD_sec2_t *file = (H5FD_sec2_t*)_file; + ssize_t nbytes; + + assert(file && file->pub.cls); + assert(buf); + + /* Check for overflow conditions */ + if (HADDR_UNDEF==addr) return -1; + if (REGION_OVERFLOW(addr, size)) return -1; + if (addr+size>file->eoa) return -1; + + /* Seek to the correct location */ + if ((addr!=file->pos || OP_WRITE!=file->op) && + file_seek(file->fd, (file_offset_t)addr, SEEK_SET)<0) { + file->pos = HADDR_UNDEF; + file->op = OP_UNKNOWN; + return -1; + } + + /* + * Write the data, being careful of interrupted system calls and partial + * results + */ + while (size>0) { + do nbytes = write(file->fd, buf, size); + while (-1==nbytes && EINTR==errno); + if (-1==nbytes) { + /* error */ + file->pos = HADDR_UNDEF; + file->op = OP_UNKNOWN; + return -1; + } + assert(nbytes>0); + assert((hsize_t)nbytes<=size); + size -= (hsize_t)nbytes; + addr += (haddr_t)nbytes; + buf = (const char*)buf + nbytes; + } + + /* Update current position and eof */ + file->pos = addr; + file->op = OP_WRITE; + if (file->pos>file->eof) file->eof = file->pos; + + return 0; +} + + +/*------------------------------------------------------------------------- + * Function: H5FD_sec2_flush + * + * Purpose: Makes sure that the true file size is the same (or larger) + * than the end-of-address. + * + * Return: Success: Non-negative + * + * Failure: Negative + * + * Programmer: Robb Matzke + * Wednesday, August 4, 1999 + * + * Modifications: + * + *------------------------------------------------------------------------- + */ +static herr_t +H5FD_sec2_flush(H5FD_t *_file) +{ + H5FD_sec2_t *file = (H5FD_sec2_t*)_file; + + if (file->eoa>file->eof) { + if (-1==file_seek(file->fd, file->eoa-1, SEEK_SET)) return -1; + if (write(file->fd, "", 1)!=1) return -1; + file->eof = file->eoa; + file->pos = file->eoa; + file->op = OP_WRITE; + } + + return 0; +} |