/* * Copyright (C) 1997 NCSA * All rights reserved. * * Programmer: Robb Matzke * Wednesday, October 22, 1997 * * Purpose: This is the Posix stdio.h I/O subclass of H5Flow. */ #include #include #include #include #include #include #include #define PABLO_MASK H5F_sec2 static hbool_t interface_initialize_g = FALSE; #define INTERFACE_INIT NULL static H5F_low_t *H5F_stdio_open (const char *name, uintn flags, H5F_search_t *key); static herr_t H5F_stdio_close (H5F_low_t *lf); static herr_t H5F_stdio_read (H5F_low_t *lf, const haddr_t *addr, size_t size, uint8 *buf); static herr_t H5F_stdio_write (H5F_low_t *lf, const haddr_t *addr, size_t size, const uint8 *buf); static herr_t H5F_stdio_flush (H5F_low_t *lf); const H5F_low_class_t H5F_LOW_STDIO[1] = {{ NULL, /* use default access(2) func */ H5F_stdio_open, /* open method */ H5F_stdio_close, /* close method */ H5F_stdio_read, /* read method */ H5F_stdio_write, /* write method */ H5F_stdio_flush, /* flush method */ NULL, /* extend method */ }}; /*------------------------------------------------------------------------- * Function: H5F_stdio_open * * Purpose: Opens a file with name NAME. The FLAGS are a bit field with * the possible values defined in H5F_low_open(). * * Bugs: H5F_ACC_EXCL has a race condition. * * 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: Low-level file pointer * * Failure: NULL * * Programmer: Robb Matzke * Wednesday, October 22, 1997 * * Modifications: * *------------------------------------------------------------------------- */ static H5F_low_t * H5F_stdio_open (const char *name, uintn flags, H5F_search_t *key/*out*/) { H5F_low_t *lf=NULL; FILE *f=NULL; struct stat sb; FUNC_ENTER (H5F_stdio_open, NULL); if (access (name, F_OK)<0) { if ((flags & H5F_ACC_CREAT) && (flags & H5F_ACC_WRITE)) { f = fopen (name, "wb+"); } else { HRETURN_ERROR (H5E_IO, H5E_CANTOPENFILE, NULL, "file doesn't exist and CREAT wasn't specified"); } } else if ((flags & H5F_ACC_CREAT) && (flags & H5F_ACC_EXCL)) { HRETURN_ERROR (H5E_IO, H5E_FILEEXISTS, NULL, "file exists but CREAT and EXCL were specified"); } else if (flags & H5F_ACC_WRITE) { if (flags & H5F_ACC_TRUNC) f = fopen (name, "wb+"); else f = fopen (name, "rb+"); } else { f = fopen (name, "rb"); } if (!f) HRETURN_ERROR (H5E_IO, H5E_CANTOPENFILE, NULL, "fopen failed"); /* Build the return value */ lf = H5MM_xcalloc (1, sizeof(H5F_low_t)); lf->u.stdio.f = f; lf->u.stdio.op = H5F_OP_SEEK; lf->u.stdio.cur = 0; H5F_addr_reset (&(lf->eof)); if (fseek (lf->u.stdio.f, 0, SEEK_END)<0) { lf->u.stdio.op = H5F_OP_UNKNOWN; } else { H5F_addr_inc (&(lf->eof), ftell (lf->u.stdio.f)); } /* The unique key */ if (key) { fstat (fileno (f), &sb); key->dev = sb.st_dev; key->ino = sb.st_ino; } FUNC_LEAVE (lf); } /*------------------------------------------------------------------------- * Function: H5F_stdio_close * * Purpose: Closes a file. * * Errors: * IO CLOSEERROR Fclose failed. * * Return: Success: SUCCEED * * Failure: FAIL * * Programmer: Robb Matzke * Wednesday, October 22, 1997 * * Modifications: * *------------------------------------------------------------------------- */ static herr_t H5F_stdio_close (H5F_low_t *lf) { FUNC_ENTER (H5F_stdio_close, FAIL); if (fclose (lf->u.stdio.f)<0) { HRETURN_ERROR (H5E_IO, H5E_CLOSEERROR, FAIL, "fclose failed"); } lf->u.stdio.f = NULL; FUNC_LEAVE (SUCCEED); } /*------------------------------------------------------------------------- * 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: Success: SUCCEED * * Failure: FAIL * * Programmer: Robb Matzke * Wednesday, October 22, 1997 * * Modifications: * *------------------------------------------------------------------------- */ static herr_t H5F_stdio_read (H5F_low_t *lf, const haddr_t *addr, size_t size, uint8 *buf) { size_t n; off_t offset; FUNC_ENTER (H5F_stdio_read, FAIL); /* Check for overflow */ offset = addr->offset; assert ("address overflowed" && offset==addr->offset); assert ("overflow" && offset+size>=offset); /* Check easy cases */ if (0==size) HRETURN (SUCCEED); if (offset>=lf->eof.offset) { HDmemset (buf, 0, size); HRETURN (SUCCEED); } /* * Seek to the correct file position. */ if (!H5F_OPT_SEEK || lf->u.stdio.op!=H5F_OP_READ || lf->u.stdio.cur!=offset) { if (fseek (lf->u.stdio.f, offset, SEEK_SET)<0) { HRETURN_ERROR (H5E_IO, H5E_SEEKERROR, FAIL, "fseek failed"); } lf->u.stdio.cur = offset; } /* * Read zeros past the logical end of file (physical is handled below) */ if ((size_t)offset+size>lf->eof.offset) { size_t nbytes = (size_t)offset+size - lf->eof.offset; HDmemset (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, lf->u.stdio.f); if (n<=0 && ferror (lf->u.stdio.f)) { lf->u.stdio.op = H5F_OP_UNKNOWN; HRETURN_ERROR (H5E_IO, H5E_READERROR, FAIL, "fread failed"); } else if (nu.stdio.op = H5F_OP_READ; lf->u.stdio.cur = offset + n; FUNC_LEAVE (SUCCEED); } /*------------------------------------------------------------------------- * 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: Success: SUCCEED * * Failure: FAIL * * Programmer: Robb Matzke * Wednesday, October 22, 1997 * * Modifications: * *------------------------------------------------------------------------- */ static herr_t H5F_stdio_write (H5F_low_t *lf, const haddr_t *addr, size_t size, const uint8 *buf) { off_t offset; FUNC_ENTER (H5F_stdio_write, FAIL); /* Check for overflow */ offset = addr->offset; assert ("address overflowed" && offset==addr->offset); assert ("overflow" && offset+size>=offset); /* * Seek to the correct file position. */ if (!H5F_OPT_SEEK || lf->u.stdio.op!=H5F_OP_WRITE || lf->u.stdio.cur!=offset) { if (fseek (lf->u.stdio.f, offset, SEEK_SET)<0) { HRETURN_ERROR (H5E_IO, H5E_SEEKERROR, FAIL, "fseek failed"); } lf->u.stdio.cur = offset; } /* * 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, lf->u.stdio.f)) { lf->u.stdio.op = H5F_OP_UNKNOWN; HRETURN_ERROR (H5E_IO, H5E_WRITEERROR, FAIL, "fwrite failed"); } /* * Update seek optimizing data. */ lf->u.stdio.op = H5F_OP_WRITE; lf->u.stdio.cur = offset + size; FUNC_LEAVE (SUCCEED); } /*------------------------------------------------------------------------- * Function: H5F_stdio_flush * * Purpose: Makes sure that all data is on disk. * * Errors: * IO WRITEERROR Fflush failed. * * Return: Success: SUCCEED * * Failure: FAIL * * Programmer: Robb Matzke * Wednesday, October 22, 1997 * * Modifications: * *------------------------------------------------------------------------- */ static herr_t H5F_stdio_flush (H5F_low_t *lf) { FUNC_ENTER (H5F_stdio_flush, FAIL); /* * What happens to the file position? Is it guaranteed to be the same * after the fflush() as it was before? */ lf->u.stdio.op = H5F_OP_UNKNOWN; /* * Flush */ if (fflush (lf->u.stdio.f)<0) { HRETURN_ERROR (H5E_IO, H5E_WRITEERROR, FAIL, "fflush failed"); } FUNC_LEAVE (SUCCEED); }