shp.h

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/*
 * Read ESRI shapefiles
 *
 * Copyright (C) 2023 Andreas Vögele
 *
 * This library is free software; you can redistribute it and/or modify it
 * under either the terms of the ISC License or the same terms as Perl.
 */
 
/* SPDX-License-Identifier: ISC OR Artistic-1.0-Perl OR GPL-1.0-or-later */
 
#ifndef _SHAPEREADER_SHP_H
#define _SHAPEREADER_SHP_H
 
#include "shp-multipatch.h"
#include "shp-multipoint.h"
#include "shp-multipointm.h"
#include "shp-multipointz.h"
#include "shp-point.h"
#include "shp-pointm.h"
#include "shp-pointz.h"
#include "shp-polygon.h"
#include "shp-polygonm.h"
#include "shp-polygonz.h"
#include "shp-polyline.h"
#include "shp-polylinem.h"
#include "shp-polylinez.h"
#include <stddef.h>
#include <stdio.h>
 
typedef enum shp_type_t {
    SHP_TYPE_NULL = 0,         
    SHP_TYPE_POINT = 1,        
    SHP_TYPE_POLYLINE = 3,     
    SHP_TYPE_POLYGON = 5,      
    SHP_TYPE_MULTIPOINT = 8,   
    SHP_TYPE_POINTZ = 11,      
    SHP_TYPE_POLYLINEZ = 13,   
    SHP_TYPE_POLYGONZ = 15,    
    SHP_TYPE_MULTIPOINTZ = 18, 
    SHP_TYPE_POINTM = 21,      
    SHP_TYPE_POLYLINEM = 23,   
    SHP_TYPE_POLYGONM = 25,    
    SHP_TYPE_MULTIPOINTM = 28, 
    SHP_TYPE_MULTIPATCH = 31   
} shp_type_t;
 
typedef struct shp_header_t {
    long file_code;   
    long unused[5];   
    size_t file_size; 
    long version;     
    shp_type_t type;  
    double x_min;     
    double y_min;     
    double x_max;     
    double y_max;     
    double z_min;     
    double z_max;     
    double m_min;     
    double m_max;     
} shp_header_t;
 
typedef struct shp_record_t {
    size_t record_number; 
    size_t record_size;   
    shp_type_t type;      
    union {
        shp_point_t point;
        shp_pointm_t pointm;
        shp_pointz_t pointz;
        shp_multipoint_t multipoint;
        shp_multipointm_t multipointm;
        shp_multipointz_t multipointz;
        shp_polyline_t polyline;
        shp_polylinem_t polylinem;
        shp_polylinez_t polylinez;
        shp_polygon_t polygon;
        shp_polygonm_t polygonm;
        shp_polygonz_t polygonz;
        shp_multipatch_t multipatch;
    } shape;
} shp_record_t;
 
typedef struct shp_file_t {
    /* File pointer */
    void *stream;
    /* Read bytes from the stream */
    size_t (*fread)(struct shp_file_t *fh, void *buf, size_t count);
    /* Test the stream's end-of-file indicator */
    int (*feof)(struct shp_file_t *fh);
    /* Test the stream's error indicator */
    int (*ferror)(struct shp_file_t *fh);
    /* Set the stream's file position */
    int (*fsetpos)(struct shp_file_t *fh, size_t offset);
    void *user_data;
    size_t num_bytes;
    char error[128];
} shp_file_t;
 
extern shp_file_t *shp_init_file(shp_file_t *fh, FILE *stream,
                                 void *user_data);
 
#ifdef __GNUC__
extern void shp_set_error(shp_file_t *fh, const char *format, ...)
    __attribute__((format(printf, 2, 3)));
#else
extern void shp_set_error(shp_file_t *fh, const char *format, ...);
#endif
 
typedef int (*shp_header_callback_t)(shp_file_t *fh,
                                     const shp_header_t *header);
 
typedef int (*shp_record_callback_t)(shp_file_t *fh,
                                     const shp_header_t *header,
                                     const shp_record_t *record,
                                     size_t file_offset);
 
extern int shp_read(shp_file_t *fh, shp_header_callback_t handle_header,
                    shp_record_callback_t handle_record);
 
extern int shp_read_header(shp_file_t *fh, shp_header_t *header);
 
extern int shp_read_record(shp_file_t *fh, shp_record_t **precord);
 
extern int shp_seek_record(shp_file_t *fh, size_t file_offset,
                           shp_record_t **precord);
 
#endif