rtpg_internal.c

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/*
 *
 * WKTRaster - Raster Types for PostGIS
 * http://trac.osgeo.org/postgis/wiki/WKTRaster
 *
 * Copyright (C) 2011-2013 Regents of the University of California
 *   <bkpark@ucdavis.edu>
 * Copyright (C) 2010-2011 Jorge Arevalo <jorge.arevalo@deimos-space.com>
 * Copyright (C) 2010-2011 David Zwarg <dzwarg@azavea.com>
 * Copyright (C) 2009-2011 Pierre Racine <pierre.racine@sbf.ulaval.ca>
 * Copyright (C) 2009-2011 Mateusz Loskot <mateusz@loskot.net>
 * Copyright (C) 2008-2009 Sandro Santilli <strk@kbt.io>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */

#include <ctype.h> /* for isspace */
#include <postgres.h> /* for palloc */
#include <executor/spi.h>

#include "rtpg_internal.h"

/* string replacement function taken from
 * http://ubuntuforums.org/showthread.php?s=aa6f015109fd7e4c7e30d2fd8b717497&t=141670&page=3
 */
/* ---------------------------------------------------------------------------
  Name       : replace - Search & replace a substring by another one.
  Creation   : Thierry Husson, Sept 2010
  Parameters :
      str    : Big string where we search
      oldstr : Substring we are looking for
      newstr : Substring we want to replace with
      count  : Optional pointer to int (input / output value). NULL to ignore.
               Input:  Maximum replacements to be done. NULL or < 1 to do all.
               Output: Number of replacements done or -1 if not enough memory.
  Returns    : Pointer to the new string or NULL if error.
  Notes      :
     - Case sensitive - Otherwise, replace functions "strstr" by "strcasestr"
     - Always allocates memory for the result.
--------------------------------------------------------------------------- */
char*
rtpg_strreplace(
        const char *str,
        const char *oldstr, const char *newstr,
        int *count
) {
        const char *tmp = str;
        char *result;
        int found = 0;
        int length, reslen;
        int oldlen = strlen(oldstr);
        int newlen = strlen(newstr);
        int limit = (count != NULL && *count > 0) ? *count : -1;

        tmp = str;
        while ((tmp = strstr(tmp, oldstr)) != NULL && found != limit)
                found++, tmp += oldlen;

        length = strlen(str) + found * (newlen - oldlen);
        if ((result = (char *) palloc(length + 1)) == NULL) {
                fprintf(stderr, "Not enough memory\n");
                found = -1;
        }
        else {
                tmp = str;
                limit = found; /* Countdown */
                reslen = 0; /* length of current result */

                /* Replace each old string found with new string  */
                while ((limit-- > 0) && (tmp = strstr(tmp, oldstr)) != NULL) {
                        length = (tmp - str); /* Number of chars to keep intouched */
                        strncpy(result + reslen, str, length); /* Original part keeped */
                        strcpy(result + (reslen += length), newstr); /* Insert new string */

                        reslen += newlen;
                        tmp += oldlen;
                        str = tmp;
                }
                strcpy(result + reslen, str); /* Copies last part and ending null char */
        }

        if (count != NULL) *count = found;
        return result;
}

char *
rtpg_strtoupper(char * str) {
        int j;

        for (j = strlen(str) - 1; j >= 0; j--)
                str[j] = toupper(str[j]);

        return str;
}

char*
rtpg_chartrim(const char *input, char *remove) {
        char *rtn = NULL;
        char *ptr = NULL;
        uint32_t offset = 0;

        if (!input)
                return NULL;
        else if (!*input)
                return (char *) input;

        /* trim left */
        while (strchr(remove, *input) != NULL)
                input++;

        /* trim right */
        ptr = ((char *) input) + strlen(input);
        while (strchr(remove, *--ptr) != NULL)
                offset++;

        rtn = palloc(sizeof(char) * (strlen(input) - offset + 1));
        if (rtn == NULL) {
                fprintf(stderr, "Not enough memory\n");
                return NULL;
        }
        strncpy(rtn, input, strlen(input) - offset);
        rtn[strlen(input) - offset] = '\0';

        return rtn;
}

/* split a string based on a delimiter */
char**
rtpg_strsplit(const char *str, const char *delimiter, int *n) {
        char *tmp = NULL;
        char **rtn = NULL;
        char *token = NULL;

        *n = 0;
        if (!str)
                return NULL;

        /* copy str to tmp as strtok will mangle the string */
        tmp = palloc(sizeof(char) * (strlen(str) + 1));
        if (NULL == tmp) {
                fprintf(stderr, "Not enough memory\n");
                return NULL;
        }
        strcpy(tmp, str);

        if (!strlen(tmp) || !delimiter || !strlen(delimiter)) {
                *n = 1;
                rtn = (char **) palloc(*n * sizeof(char *));
                if (NULL == rtn) {
                        fprintf(stderr, "Not enough memory\n");
                        return NULL;
                }
                rtn[0] = (char *) palloc(sizeof(char) * (strlen(tmp) + 1));
                if (NULL == rtn[0]) {
                        fprintf(stderr, "Not enough memory\n");
                        return NULL;
                }
                strcpy(rtn[0], tmp);
                pfree(tmp);
                return rtn;
        }

        token = strtok(tmp, delimiter);
        while (token != NULL) {
                if (*n < 1) {
                        rtn = (char **) palloc(sizeof(char *));
                }
                else {
                        rtn = (char **) repalloc(rtn, (*n + 1) * sizeof(char *));
                }
                if (NULL == rtn) {
                        fprintf(stderr, "Not enough memory\n");
                        return NULL;
                }

                rtn[*n] = NULL;
                rtn[*n] = (char *) palloc(sizeof(char) * (strlen(token) + 1));
                if (NULL == rtn[*n]) {
                        fprintf(stderr, "Not enough memory\n");
                        return NULL;
                }

                strcpy(rtn[*n], token);
                *n = *n + 1;

                token = strtok(NULL, delimiter);
        }

        pfree(tmp);
        return rtn;
}

char *
rtpg_removespaces(char *str) {
        char *rtn;
        char *tmp;

        rtn = rtpg_strreplace(str, " ", "", NULL);

        tmp = rtpg_strreplace(rtn, "\n", "", NULL);
        pfree(rtn);
        rtn = rtpg_strreplace(tmp, "\t", "", NULL);
        pfree(tmp);
        tmp = rtpg_strreplace(rtn, "\f", "", NULL);
        pfree(rtn);
        rtn = rtpg_strreplace(tmp, "\r", "", NULL);
        pfree(tmp);

        return rtn;
}

char*
rtpg_trim(const char *input) {
        char *rtn;
        char *ptr;
        uint32_t offset = 0;
        int inputlen = 0;

        if (!input)
                return NULL;
        else if (!*input)
                return (char *) input;

        /* trim left */
        while (isspace(*input) && *input != '\0')
                input++;

        /* trim right */
        inputlen = strlen(input);
        if (inputlen) {
                ptr = ((char *) input) + inputlen;
                while (isspace(*--ptr))
                        offset++;
        }

        rtn = palloc(sizeof(char) * (inputlen - offset + 1));
        if (rtn == NULL) {
                fprintf(stderr, "Not enough memory\n");
                return NULL;
        }
        strncpy(rtn, input, inputlen - offset);
        rtn[inputlen - offset] = '\0';

        return rtn;
}

/*
 * reverse string search function from
 * http://stackoverflow.com/a/1634398
 */
char *
rtpg_strrstr(const char *s1, const char *s2) {
        int s1len = strlen(s1);
        int s2len = strlen(s2);
        char *s;

        if (s2len > s1len)
                return NULL;

        s = (char *) (s1 + s1len - s2len);
        for (; s >= s1; --s)
                if (strncmp(s, s2, s2len) == 0)
                        return s;

        return NULL;
}

char*
rtpg_getSR(int srid) {
        int i = 0;
        int len = 0;
        char *sql = NULL;
        int spi_result;
        TupleDesc tupdesc;
        SPITupleTable *tuptable = NULL;
        HeapTuple tuple;
        char *tmp = NULL;
        char *srs = NULL;

/*
SELECT
        CASE
                WHEN (upper(auth_name) = 'EPSG' OR upper(auth_name) = 'EPSGA') AND length(COALESCE(auth_srid::text, '')) > 0
                        THEN upper(auth_name) || ':' || auth_srid
                WHEN length(COALESCE(auth_name, '') || COALESCE(auth_srid::text, '')) > 0
                        THEN COALESCE(auth_name, '') || COALESCE(auth_srid::text, '')
                ELSE ''
        END,
        proj4text,
        srtext
FROM spatial_ref_sys
WHERE srid = X
LIMIT 1
*/

        len = sizeof(char) * (strlen("SELECT CASE WHEN (upper(auth_name) = 'EPSG' OR upper(auth_name) = 'EPSGA') AND length(COALESCE(auth_srid::text, '')) > 0 THEN upper(auth_name) || ':' || auth_srid WHEN length(COALESCE(auth_name, '') || COALESCE(auth_srid::text, '')) > 0 THEN COALESCE(auth_name, '') || COALESCE(auth_srid::text, '') ELSE '' END, proj4text, srtext FROM spatial_ref_sys WHERE srid =  LIMIT 1") + MAX_INT_CHARLEN + 1);
        sql = (char *) palloc(len);
        if (NULL == sql) {
                elog(ERROR, "rtpg_getSR: Could not allocate memory for sql\n");
                return NULL;
        }

        spi_result = SPI_connect();
        if (spi_result != SPI_OK_CONNECT) {
                pfree(sql);
                elog(ERROR, "rtpg_getSR: Could not connect to database using SPI\n");
                return NULL;
        }

        /* execute query */
        snprintf(sql, len, "SELECT CASE WHEN (upper(auth_name) = 'EPSG' OR upper(auth_name) = 'EPSGA') AND length(COALESCE(auth_srid::text, '')) > 0 THEN upper(auth_name) || ':' || auth_srid WHEN length(COALESCE(auth_name, '') || COALESCE(auth_srid::text, '')) > 0 THEN COALESCE(auth_name, '') || COALESCE(auth_srid::text, '') ELSE '' END, proj4text, srtext FROM spatial_ref_sys WHERE srid = %d LIMIT 1", srid);
        POSTGIS_RT_DEBUGF(4, "SRS query: %s", sql);
        spi_result = SPI_execute(sql, TRUE, 0);
        SPI_pfree(sql);
        if (spi_result != SPI_OK_SELECT || SPI_tuptable == NULL || SPI_processed != 1) {
                if (SPI_tuptable) SPI_freetuptable(tuptable);
                SPI_finish();
                elog(ERROR, "rtpg_getSR: Cannot find SRID (%d) in spatial_ref_sys", srid);
                return NULL;
        }

        tupdesc = SPI_tuptable->tupdesc;
        tuptable = SPI_tuptable;
        tuple = tuptable->vals[0];

        /* which column to use? */
        for (i = 1; i < 4; i++) {
                tmp = SPI_getvalue(tuple, tupdesc, i);

                /* value AND GDAL supports this SR */
                if (
                        SPI_result != SPI_ERROR_NOATTRIBUTE &&
                        SPI_result != SPI_ERROR_NOOUTFUNC &&
                        tmp != NULL &&
                        strlen(tmp) &&
                        rt_util_gdal_supported_sr(tmp)
                ) {
                        POSTGIS_RT_DEBUGF(4, "Value for column %d is %s", i, tmp);

                        len = strlen(tmp) + 1;
                        srs = SPI_palloc(sizeof(char) * len);
                        if (NULL == srs) {
                                pfree(tmp);
                                if (SPI_tuptable) SPI_freetuptable(tuptable);
                                SPI_finish();
                                elog(ERROR, "rtpg_getSR: Could not allocate memory for spatial reference text\n");
                                return NULL;
                        }
                        strncpy(srs, tmp, len);
                        pfree(tmp);

                        break;
                }

                if (tmp != NULL)
                        pfree(tmp);
                continue;
        }

        if (SPI_tuptable) SPI_freetuptable(tuptable);
        SPI_finish();

        /* unable to get SR info */
        if (srs == NULL) {
                if (SPI_tuptable) SPI_freetuptable(tuptable);
                SPI_finish();
                elog(ERROR, "rtpg_getSR: Could not find a viable spatial reference for SRID (%d)", srid);
                return NULL;
        }

        return srs;
}