src/img.h

   1 /* img.h
   2  * Header file for routines to read and write processed survey data files
   3  *
   4  * These routines support reading processed survey data in a variety of formats
   5  * - currently:
   6  *
   7  * - Survex ".3d" image files
   8  * - Survex ".pos" files
   9  * - Compass Plot files (".plt" and ".plf")
  10  * - CMAP XYZ files (".sht", ".adj", ".una", ".xyz")
  11  *
  12  * Writing Survex ".3d" image files is supported.
  13  *
  14  * Copyright (C) Olly Betts 1993,1994,1997,2001,2002,2003,2004,2005,2006,2010,2011,2012,2013,2014,2016,2018
  15  *
  16  * This program is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License as published by
  18  * the Free Software Foundation; either version 2 of the License, or
  19  * (at your option) any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  * GNU General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program; if not, write to the Free Software
  28  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  29  */
  30
  31 #ifndef IMG_H
  32 # define IMG_H
  33
  34 /* Define IMG_API_VERSION if you want more recent versions of the img API.
  35  *
  36  * 0 (default)  The old API.  date1 and date2 give the survey date as time_t.
  37  *              Set to 0 for "unknown".
  38  * 1            days1 and days2 give survey dates as days since 1st Jan 1900.
  39  *              Set to -1 for "unknown".
  40  */
  41 #ifndef IMG_API_VERSION
  42 # define IMG_API_VERSION 0
  43 #elif IMG_API_VERSION > 1
  44 # error IMG_API_VERSION > 1 too new
  45 #endif
  46
  47 #ifdef __cplusplus
  48 extern "C" {
  49 #endif
  50
  51 #include <stdio.h>
  52 #include <time.h> /* for time_t */
  53
  54 # define img_BAD   -2
  55 # define img_STOP  -1
  56 # define img_MOVE   0
  57 # define img_LINE   1
  58 /* NB: img_CROSS is never output and ignored on input.
  59  * Put crosses where labels are. */
  60 /* # define img_CROSS  2 */
  61 # define img_LABEL  3
  62 # define img_XSECT  4
  63 # define img_XSECT_END 5
  64 /* Loop closure information for the *preceding* traverse (img_MOVE + one or
  65  * more img_LINEs). */
  66 # define img_ERROR_INFO 6
  67
  68 /* Leg flags */
  69 # define img_FLAG_SURFACE   0x01
  70 # define img_FLAG_DUPLICATE 0x02
  71 # define img_FLAG_SPLAY     0x04
  72
  73 /* Station flags */
  74 # define img_SFLAG_SURFACE     0x01
  75 # define img_SFLAG_UNDERGROUND 0x02
  76 # define img_SFLAG_ENTRANCE    0x04
  77 # define img_SFLAG_EXPORTED    0x08
  78 # define img_SFLAG_FIXED       0x10
  79 # define img_SFLAG_ANON        0x20
  80 # define img_SFLAG_WALL        0x40
  81
  82 /* File-wide flags */
  83 # define img_FFLAG_EXTENDED 0x80
  84
  85 /* When writing img_XSECT, img_XFLAG_END in pimg->flags means this is the last
  86  * img_XSECT in this tube:
  87  */
  88 # define img_XFLAG_END      0x01
  89
  90 # define img_STYLE_UNKNOWN   -1
  91 # define img_STYLE_NORMAL     0
  92 # define img_STYLE_DIVING     1
  93 # define img_STYLE_CARTESIAN  2
  94 # define img_STYLE_CYLPOLAR   3
  95 # define img_STYLE_NOSURVEY   4
  96
  97 /* 3D coordinates (in metres) */
  98 typedef struct {
  99    double x, y, z;
 100 } img_point;
 101
 102 typedef struct {
 103    /* Members you can access when reading (don't touch when writing): */
 104    char *label;
 105    int flags;
 106    char *title;
 107    /* If the coordinate system was specified, this contains a PROJ4 string
 108     * describing it.  If not, this member will be NULL.
 109     */
 110    char *cs;
 111    /* Older .3d format versions stored a human readable datestamp string.
 112     * Format versions >= 8 versions store a string consisting of "@" followed
 113     * by the number of seconds since midnight UTC on 1/1/1970.  Some foreign
 114     * formats contain a human readable string, others no date information
 115     * (which results in "?" being returned).
 116     */
 117    char *datestamp;
 118    /* The datestamp as a time_t (or (time_t)-1 if not available).
 119     *
 120     * For 3d format versions >= 8, this is a reliable value and in UTC.  Older
 121     * 3d format versions store a human readable time, which img will attempt
 122     * to decode, but it may fail, particularly with handling timezones.  Even
 123     * if it does work, beware that times in local time where DST applies are
 124     * inherently ambiguous around when the clocks go back.
 125     *
 126     * CMAP XYZ files contain a timestamp.  It's probably in localtime (but
 127     * without any timezone information) and the example files are all pre-2000
 128     * and have two digit years.  We do our best to turn these into a useful
 129     * time_t value.
 130     */
 131    time_t datestamp_numeric;
 132    char separator; /* character used to separate survey levels ('.' usually) */
 133
 134    /* Members that can be set when writing: */
 135 #if IMG_API_VERSION == 0
 136    time_t date1, date2;
 137 #else /* IMG_API_VERSION == 1 */
 138    int days1, days2;
 139 #endif
 140    double l, r, u, d;
 141
 142    /* Error information - valid when img_ERROR_INFO is returned: */
 143    int n_legs;
 144    double length;
 145    double E, H, V;
 146
 147    /* The filename actually opened (e.g. may have ".3d" added).
 148     *
 149     * This is only set if img opened the filename - if an existing stream
 150     * is used (via img_read_stream() or similar) then this member will be
 151     * NULL.
 152     */
 153    char * filename_opened;
 154
 155    /* Non-zero if reading an extended elevation: */
 156    int is_extended_elevation;
 157
 158    /* Members that can be set when writing: */
 159    /* The style of the data - one of the img_STYLE_* constants above */
 160    int style;
 161
 162    /* All other members are for internal use only: */
 163    FILE *fh;          /* file handle of image file */
 164    int (*close_func)(FILE*);
 165    char *label_buf;
 166    size_t buf_len;
 167    size_t label_len;
 168    int fRead;        /* 1 for reading, 0 for writing */
 169    long start;
 170    /* version of file format:
 171     *  -4 => CMAP .xyz file, shot format
 172     *  -3 => CMAP .xyz file, station format
 173     *  -2 => Compass .plt file
 174     *  -1 => .pos file
 175     *   0 => 0.01 ascii
 176     *   1 => 0.01 binary,
 177     *   2 => byte actions and flags
 178     *   3 => prefixes for legs; compressed prefixes
 179     *   4 => survey date
 180     *   5 => LRUD info
 181     *   6 => error info
 182     *   7 => more compact dates with wider range
 183     *   8 => lots of changes
 184     */
 185    int version;
 186    char *survey;
 187    size_t survey_len;
 188    int pending; /* for old style text format files and survey filtering */
 189    img_point mv;
 190 #if IMG_API_VERSION == 0
 191    time_t olddate1, olddate2;
 192 #else /* IMG_API_VERSION == 1 */
 193    int olddays1, olddays2;
 194 #endif
 195    int oldstyle;
 196 } img;
 197
 198 /* Which version of the file format to output (defaults to newest) */
 199 extern unsigned int img_output_version;
 200
 201 /* Minimum supported value for img_output_version: */
 202 #define IMG_VERSION_MIN 1
 203
 204 /* Maximum supported value for img_output_version: */
 205 #define IMG_VERSION_MAX 8
 206
 207 /* Open a processed survey data file for reading
 208  *
 209  * fnm is the filename
 210  *
 211  * Returns pointer to an img struct or NULL
 212  */
 213 #define img_open(F) img_open_survey((F), NULL)
 214
 215 /* Open a processed survey data file for reading
 216  *
 217  * fnm is the filename
 218  *
 219  * survey points to a survey name to restrict reading to (or NULL for all
 220  * survey data in the file)
 221  *
 222  * Returns pointer to an img struct or NULL
 223  */
 224 img *img_open_survey(const char *fnm, const char *survey);
 225
 226 /* Read processed survey data from an existing stream.
 227  *
 228  * stream is a FILE* open on the stream (can be NULL which will give error
 229  * IMG_FILENOTFOUND so you don't need to handle that case specially).  The
 230  * stream should be opened for reading in binary mode and positioned at the
 231  * start of the survey data file.
 232  *
 233  * close_func is a function to call to close the stream (most commonly
 234  * fclose, or pclose if the stream was opened using popen()) or NULL if
 235  * the caller wants to take care of closing the stream.
 236  *
 237  * filename is used to determine the format based on the file extension,
 238  * and also the leafname with the extension removed is used for the survey
 239  * title for formats which don't support a title or when no title is
 240  * specified.  If you're not interested in default titles, you can just
 241  * pass the extension including a leading "." - e.g. ".3d".  May not be
 242  * NULL.
 243  *
 244  * Returns pointer to an img struct or NULL on error.  Any close function
 245  * specified is called on error (unless stream is NULL).
 246  */
 247 #define img_read_stream(S, C, F) img_read_stream_survey((S), (C), (F), NULL)
 248
 249 /* Read processed survey data from an existing stream.
 250  *
 251  * stream is a FILE* open on the stream (can be NULL which will give error
 252  * IMG_FILENOTFOUND so you don't need to handle that case specially).  The
 253  * stream should be opened for reading in binary mode and positioned at the
 254  * start of the survey data file.
 255  *
 256  * close_func is a function to call to close the stream (most commonly
 257  * fclose, or pclose if the stream was opened using popen()) or NULL if
 258  * the caller wants to take care of closing the stream.
 259  *
 260  * filename is used to determine the format based on the file extension,
 261  * and also the leafname with the extension removed is used for the survey
 262  * title for formats which don't support a title or when no title is
 263  * specified.  If you're not interested in default titles, you can just
 264  * pass the extension including a leading "." - e.g. ".3d".  filename must
 265  * not be NULL.
 266  *
 267  * survey points to a survey name to restrict reading to (or NULL for all
 268  * survey data in the file)
 269  *
 270  * Returns pointer to an img struct or NULL on error.  Any close function
 271  * specified is called on error.
 272  */
 273 img *img_read_stream_survey(FILE *stream, int (*close_func)(FILE*),
 274                             const char *filename,
 275                             const char *survey);
 276
 277 /* Open a .3d file for output with no specified coordinate system
 278  *
 279  * This is a very thin wrapper around img_open_write_cs() which passes NULL for
 280  * cs, provided for compatibility with the API provided before support for
 281  * coordinate systems was added.
 282  *
 283  * See img_open_write_cs() for documentation.
 284  */
 285 #define img_open_write(F, T, S) img_open_write_cs(F, T, NULL, S)
 286
 287 /* Open a .3d file for output in a specified coordinate system
 288  *
 289  * fnm is the filename
 290  *
 291  * title is the title
 292  *
 293  * cs is a PROJ4 string describing the coordinate system (or NULL to not
 294  * specify a coordinate system).
 295  *
 296  * flags contains a bitwise-or of any file-wide flags - currently only one
 297  * is available: img_FFLAG_EXTENDED.
 298  *
 299  * Returns pointer to an img struct or NULL for error (check img_error()
 300  * for details)
 301  */
 302 img *img_open_write_cs(const char *fnm, const char *title, const char * cs,
 303                        int flags);
 304
 305 /* Write a .3d file to a stream
 306  *
 307  * stream is a FILE* open on the stream (can be NULL which will give error
 308  * IMG_FILENOTFOUND so you don't need to handle that case specially).  The
 309  * stream should be opened for writing in binary mode.
 310  *
 311  * close_func is a function to call to close the stream (most commonly
 312  * fclose, or pclose if the stream was opened using popen()) or NULL if
 313  * the caller wants to take care of closing the stream.
 314  *
 315  * title is the title
 316  *
 317  * cs is a PROJ4 string describing the coordinate system (or NULL to not
 318  * specify a coordinate system).
 319  *
 320  * flags contains a bitwise-or of any file-wide flags - currently only one
 321  * is available: img_FFLAG_EXTENDED.
 322  *
 323  * Returns pointer to an img struct or NULL for error (check img_error()
 324  * for details).  Any close function specified is called on error (unless
 325  * stream is NULL).
 326  */
 327 img *img_write_stream(FILE *stream, int (*close_func)(FILE*),
 328                       const char *title, const char * cs, int flags);
 329
 330 /* Read an item from a processed survey data file
 331  *
 332  * pimg is a pointer to an img struct returned by img_open()
 333  *
 334  * coordinates are returned in p
 335  *
 336  * flags and label name are returned in fields in pimg
 337  *
 338  * Returns img_XXXX as #define-d above
 339  */
 340 int img_read_item(img *pimg, img_point *p);
 341
 342 /* Write a item to a .3d file
 343  *
 344  * pimg is a pointer to an img struct returned by img_open_write()
 345  *
 346  * code is one of the img_XXXX #define-d above
 347  *
 348  * flags is the leg, station, or xsect flags
 349  * (meaningful for img_LINE, img_LABEL, and img_XSECT respectively)
 350  *
 351  * s is the label (only meaningful for img_LABEL)
 352  *
 353  * x, y, z are the coordinates
 354  */
 355 void img_write_item(img *pimg, int code, int flags, const char *s,
 356                     double x, double y, double z);
 357
 358 /* Write error information for the current traverse
 359  *
 360  * n_legs is the number of legs in the traverse
 361  *
 362  * length is the traverse length (in m)
 363  *
 364  * E is the ratio of the observed misclosure to the theoretical one
 365  *
 366  * H is the ratio of the observed horizontal misclosure to the theoretical one
 367  *
 368  * V is the ratio of the observed vertical misclosure to the theoretical one
 369  */
 370 void img_write_errors(img *pimg, int n_legs, double length,
 371                       double E, double H, double V);
 372
 373 /* rewind a processed survey data file opened for reading
 374  *
 375  * This is useful if you want to read the data in several passes.
 376  *
 377  * pimg is a pointer to an img struct returned by img_open()
 378  *
 379  * Returns: non-zero for success, zero for error (check img_error() for
 380  *   details)
 381  */
 382 int img_rewind(img *pimg);
 383
 384 /* Close a processed survey data file
 385  *
 386  * pimg is a pointer to an img struct returned by img_open() or
 387  *   img_open_write()
 388  *
 389  * Returns: non-zero for success, zero for error (check img_error() for
 390  *   details)
 391  */
 392 int img_close(img *pimg);
 393
 394 /* Codes returned by img_error */
 395 typedef enum {
 396    IMG_NONE = 0, IMG_FILENOTFOUND, IMG_OUTOFMEMORY,
 397    IMG_CANTOPENOUT, IMG_BADFORMAT, IMG_DIRECTORY,
 398    IMG_READERROR, IMG_WRITEERROR, IMG_TOONEW
 399 } img_errcode;
 400
 401 /* Read the error code
 402  *
 403  * If img_open(), img_open_survey() or img_open_write() returns NULL, or
 404  * img_rewind() or img_close() returns 0, or img_read_item() returns img_BAD
 405  * then you can call this function to discover why.
 406  */
 407 img_errcode img_error(void);
 408
 409 #ifdef __cplusplus
 410 }
 411 #endif
 412
 413 #endif