shpdump.c

/******************************************************************************
 *
 * Project:  Shapelib
 * Purpose:  Sample application for dumping contents of a shapefile to
 *           the terminal in human readable form.
 * Author:   Frank Warmerdam, warmerdam@pobox.com
 *
 ******************************************************************************
 * Copyright (c) 1999, Frank Warmerdam
 *
 * SPDX-License-Identifier: MIT OR LGPL-2.0-or-later
 ******************************************************************************
 *
 */

#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "shapefil.h"

int main(int argc, char **argv)
{
    bool bValidate = false;
    if (argc > 1 && strcmp(argv[1], "-validate") == 0)
    {
        bValidate = true;
        argv++;
        argc--;
    }

    bool bHeaderOnly = false;
    if (argc > 1 && strcmp(argv[1], "-ho") == 0)
    {
        bHeaderOnly = true;
        argv++;
        argc--;
    }

    int nPrecision = 15;
    if (argc > 2 && strcmp(argv[1], "-precision") == 0)
    {
        nPrecision = atoi(argv[2]);
        argv += 2;
        argc -= 2;
    }

    /* -------------------------------------------------------------------- */
    /*      Display a usage message.                                        */
    /* -------------------------------------------------------------------- */
    if (argc != 2)
    {
        printf("shpdump [-validate] [-ho] [-precision number] shp_file\n");
        exit(1);
    }

    /* -------------------------------------------------------------------- */
    /*      Open the passed shapefile.                                      */
    /* -------------------------------------------------------------------- */
    SHPHandle hSHP = SHPOpen(argv[1], "rb");
    if (hSHP == NULL)
    {
        printf("Unable to open:%s\n", argv[1]);
        exit(1);
    }

    /* -------------------------------------------------------------------- */
    /*      Print out the file bounds.                                      */
    /* -------------------------------------------------------------------- */
    int nEntities;
    int nShapeType;
    double adfMinBound[4];
    double adfMaxBound[4];
    SHPGetInfo(hSHP, &nEntities, &nShapeType, adfMinBound, adfMaxBound);

    printf("Shapefile Type: %s   # of Shapes: %d\n\n", SHPTypeName(nShapeType),
           nEntities);

    printf("File Bounds: (%.*g,%.*g,%.*g,%.*g)\n"
           "         to  (%.*g,%.*g,%.*g,%.*g)\n",
           nPrecision, adfMinBound[0], nPrecision, adfMinBound[1], nPrecision,
           adfMinBound[2], nPrecision, adfMinBound[3], nPrecision,
           adfMaxBound[0], nPrecision, adfMaxBound[1], nPrecision,
           adfMaxBound[2], nPrecision, adfMaxBound[3]);

    /* -------------------------------------------------------------------- */
    /*	Skim over the list of shapes, printing all the vertices.	*/
    /* -------------------------------------------------------------------- */
    int nInvalidCount = 0;

    for (int i = 0; i < nEntities && !bHeaderOnly; i++)
    {
        SHPObject *psShape = SHPReadObject(hSHP, i);

        if (psShape == NULL)
        {
            fprintf(stderr,
                    "Unable to read shape %d, terminating object reading.\n",
                    i);
            break;
        }

        if (psShape->bMeasureIsUsed)
            printf("\nShape:%d (%s)  nVertices=%d, nParts=%d\n"
                   "  Bounds:(%.*g,%.*g, %.*g, %.*g)\n"
                   "      to (%.*g,%.*g, %.*g, %.*g)\n",
                   i, SHPTypeName(psShape->nSHPType), psShape->nVertices,
                   psShape->nParts, nPrecision, psShape->dfXMin, nPrecision,
                   psShape->dfYMin, nPrecision, psShape->dfZMin, nPrecision,
                   psShape->dfMMin, nPrecision, psShape->dfXMax, nPrecision,
                   psShape->dfYMax, nPrecision, psShape->dfZMax, nPrecision,
                   psShape->dfMMax);
        else
            printf("\nShape:%d (%s)  nVertices=%d, nParts=%d\n"
                   "  Bounds:(%.*g,%.*g, %.*g)\n"
                   "      to (%.*g,%.*g, %.*g)\n",
                   i, SHPTypeName(psShape->nSHPType), psShape->nVertices,
                   psShape->nParts, nPrecision, psShape->dfXMin, nPrecision,
                   psShape->dfYMin, nPrecision, psShape->dfZMin, nPrecision,
                   psShape->dfXMax, nPrecision, psShape->dfYMax, nPrecision,
                   psShape->dfZMax);

        if (psShape->nParts > 0 && psShape->panPartStart[0] != 0)
        {
            fprintf(stderr, "panPartStart[0] = %d, not zero as expected.\n",
                    psShape->panPartStart[0]);
        }

        for (int j = 0, iPart = 1; j < psShape->nVertices; j++)
        {
            const char *pszPartType = "";

            if (j == 0 && psShape->nParts > 0)
                pszPartType = SHPPartTypeName(psShape->panPartType[0]);

            const char *pszPlus;
            if (iPart < psShape->nParts && psShape->panPartStart[iPart] == j)
            {
                pszPartType = SHPPartTypeName(psShape->panPartType[iPart]);
                iPart++;
                pszPlus = "+";
            }
            else
                pszPlus = " ";

            if (psShape->bMeasureIsUsed)
                printf("   %s (%.*g,%.*g, %.*g, %.*g) %s \n", pszPlus,
                       nPrecision, psShape->padfX[j], nPrecision,
                       psShape->padfY[j], nPrecision, psShape->padfZ[j],
                       nPrecision, psShape->padfM[j], pszPartType);
            else
                printf("   %s (%.*g,%.*g, %.*g) %s \n", pszPlus, nPrecision,
                       psShape->padfX[j], nPrecision, psShape->padfY[j],
                       nPrecision, psShape->padfZ[j], pszPartType);
        }

        if (bValidate)
        {
            int nAltered = SHPRewindObject(hSHP, psShape);

            if (nAltered > 0)
            {
                printf("  %d rings wound in the wrong direction.\n", nAltered);
                nInvalidCount++;
            }
        }

        SHPDestroyObject(psShape);
    }

    SHPClose(hSHP);

    if (bValidate)
    {
        printf("%d object has invalid ring orderings.\n", nInvalidCount);
    }

    exit(0);
}