src/gromacs/fileio/gmxfio.h

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  37
  38 #ifndef GMX_FILEIO_GMXFIO_H
  39 #define GMX_FILEIO_GMXFIO_H
  40
  41 #include <stdio.h>
  42
  43 #include "gromacs/math/vectypes.h"
  44 #include "gromacs/utility/cstringutil.h"
  45 #include "gromacs/utility/futil.h"
  46 #include "gromacs/utility/real.h"
  47
  48 #ifdef __cplusplus
  49 extern "C" {
  50 #endif
  51
  52 typedef struct t_fileio t_fileio;
  53
  54 /* NOTE ABOUT THREAD SAFETY:
  55
  56    The functions are all thread-safe, provided that two threads don't
  57    do something silly like closing the same file, or one thread
  58    accesses a file that has been closed by another.
  59  */
  60
  61 /********************************************************
  62  * Open and Close
  63  ********************************************************/
  64
  65 t_fileio *gmx_fio_open(const char *fn, const char *mode);
  66 /* Open a new file for reading or writing.
  67  * The file type will be deduced from the file name.
  68  */
  69
  70 int gmx_fio_close(t_fileio *fp);
  71 /* Close the file corresponding to fp (if not stdio)
  72  * The routine will exit when an invalid fio is handled.
  73  * Returns 0 on success.
  74  */
  75
  76 int gmx_fio_fp_close(t_fileio *fp);
  77 /* Close the file corresponding to fp without closing the FIO entry
  78  * Needed e.g. for trxio because the FIO entries are used to store
  79  * additional data.
  80  * NOTE that the fp still needs to be properly closed with gmx_fio_close().
  81  * The routine will exit when an invalid fio is handled.
  82  * Returns 0 on success.
  83  */
  84
  85
  86 /* Open a file, return a stream, record the entry in internal FIO object */
  87 FILE* gmx_fio_fopen(const char *fn, const char *mode);
  88
  89 /* Close a file previously opened with gmx_fio_fopen.
  90  * Do not mix these calls with standard fopen/fclose ones!
  91  * Returns 0 on success.  */
  92 int gmx_fio_fclose(FILE *fp);
  93
  94
  95
  96 /********************************************************
  97  * Change properties of the open file
  98  ********************************************************/
  99
 100 char *gmx_fio_getname(t_fileio *fio);
 101 /* Return the filename corresponding to the fio index */
 102
 103 int gmx_fio_getftp(t_fileio *fio);
 104 /* Return the filetype corresponding to the fio index.
 105     There is as of now no corresponding setftp function because the file
 106     was opened as a specific file type and changing that midway is most
 107     likely an evil hack. */
 108
 109 gmx_bool gmx_fio_getread(t_fileio *fio);
 110 /* Return  whether read mode is on in fio  */
 111
 112 /***************************************************
 113  * FILE Operations
 114  ***************************************************/
 115
 116 void gmx_fio_rewind(t_fileio *fio);
 117 /* Rewind the file in fio */
 118
 119 int gmx_fio_flush(t_fileio *fio);
 120 /* Flush the fio, returns 0 on success */
 121
 122 int gmx_fio_fsync(t_fileio *fio);
 123 /* fsync the fio, returns 0 on success.
 124    NOTE: don't use fsync function unless you're absolutely sure you need it
 125    because it deliberately interferes with the OS's caching mechanisms and
 126    can cause dramatically slowed down IO performance. Some OSes (Linux,
 127    for example), may implement fsync as a full sync() point. */
 128
 129 gmx_off_t gmx_fio_ftell(t_fileio *fio);
 130 /* Return file position if possible */
 131
 132 int gmx_fio_seek(t_fileio *fio, gmx_off_t fpos);
 133 /* Set file position if possible, quit otherwise */
 134
 135 FILE *gmx_fio_getfp(t_fileio *fio);
 136 /* Return the file pointer itself */
 137
 138
 139 /* Element with information about position in a currently open file.
 140  * gmx_off_t should be defined by autoconf if your system does not have it.
 141  * If you do not have it on some other platform you do not have largefile
 142  * support at all, and you can define it to int (or better, find out how to
 143  * enable large files).  */
 144 typedef struct gmx_file_position_t
 145 {
 146     char          filename[STRLEN];
 147     gmx_off_t     offset;
 148     unsigned char chksum[16];
 149     int           chksum_size;
 150 }
 151 gmx_file_position_t;
 152
 153 int gmx_fio_get_output_file_positions(gmx_file_position_t ** outputfiles,
 154                                       int                   *nfiles );
 155 /* Return the name and file pointer positions for all currently open
 156  * output files. This is used for saving in the checkpoint files, so we
 157  * can truncate output files upon restart-with-appending.
 158  *
 159  * For the first argument you should use a pointer, which will be set to
 160  * point to a list of open files.
 161  */
 162
 163 t_fileio *gmx_fio_all_output_fsync(void);
 164 /* fsync all open output files. This is used for checkpointing, where
 165    we need to ensure that all output is actually written out to
 166    disk.
 167    This is most important in the case of some networked file systems,
 168    where data is not synced with the file server until close() or
 169    fsync(), so data could remain in cache for days.
 170    Note the caveats reported with gmx_fio_fsync().
 171
 172     returns: NULL if no error occurred, or a pointer to the first file that
 173              failed if an error occurred
 174  */
 175
 176
 177 int gmx_fio_get_file_md5(t_fileio *fio, gmx_off_t offset,
 178                          unsigned char digest[]);
 179
 180
 181 int xtc_seek_time(t_fileio *fio, real time, int natoms, gmx_bool bSeekForwardOnly);
 182
 183
 184 #ifdef __cplusplus
 185 }
 186 #endif
 187
 188 #endif