lwutil.c

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/**********************************************************************
 *
 * PostGIS - Spatial Types for PostgreSQL
 * http://postgis.net
 *
 * PostGIS 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.
 *
 * PostGIS 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 PostGIS.  If not, see <http://www.gnu.org/licenses/>.
 *
 **********************************************************************
 *
 * Copyright (C) 2004-2015 Sandro Santilli <strk@kbt.io>
 * Copyright (C) 2006 Mark Leslie <mark.leslie@lisasoft.com>
 * Copyright (C) 2008-2009 Mark Cave-Ayland <mark.cave-ayland@siriusit.co.uk>
 * Copyright (C) 2009-2015 Paul Ramsey <pramsey@cleverelephant.ca>
 * Copyright (C) 2010 Olivier Courtin <olivier.courtin@camptocamp.com>
 *
 **********************************************************************/
 
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <ctype.h> /* for tolower */
 
/* Global variables */
#include "../postgis_config.h"
#include "liblwgeom_internal.h"
#include "lwgeom_log.h"
 
/* Default allocators */
static void * default_allocator(size_t size);
static void default_freeor(void *mem);
static void * default_reallocator(void *mem, size_t size);
lwallocator lwalloc_var = default_allocator;
lwreallocator lwrealloc_var = default_reallocator;
lwfreeor lwfree_var = default_freeor;
 
/* Default reporters */
static void default_noticereporter(const char *fmt, va_list ap);
static void default_errorreporter(const char *fmt, va_list ap);
lwreporter lwnotice_var = default_noticereporter;
lwreporter lwerror_var = default_errorreporter;
 
/* Default logger */
static void default_debuglogger(int level, const char *fmt, va_list ap);
lwdebuglogger lwdebug_var = default_debuglogger;
 
#define LW_MSG_MAXLEN 256
 
static char *lwgeomTypeName[] =
{
        "Unknown",
        "Point",
        "LineString",
        "Polygon",
        "MultiPoint",
        "MultiLineString",
        "MultiPolygon",
        "GeometryCollection",
        "CircularString",
        "CompoundCurve",
        "CurvePolygon",
        "MultiCurve",
        "MultiSurface",
        "PolyhedralSurface",
        "Triangle",
        "Tin"
};
 
/*
 * Default allocators
 *
 * We include some default allocators that use malloc/free/realloc
 * along with stdout/stderr since this is the most common use case
 *
 */
 
static void *
default_allocator(size_t size)
{
        void *mem = malloc(size);
        return mem;
}
 
static void
default_freeor(void *mem)
{
        free(mem);
}
 
static void *
default_reallocator(void *mem, size_t size)
{
        void *ret = realloc(mem, size);
        return ret;
}
 
/*
 * Default lwnotice/lwerror handlers
 *
 * Since variadic functions cannot pass their parameters directly, we need
 * wrappers for these functions to convert the arguments into a va_list
 * structure.
 */
 
static void
default_noticereporter(const char *fmt, va_list ap)
{
        char msg[LW_MSG_MAXLEN+1];
        vsnprintf (msg, LW_MSG_MAXLEN, fmt, ap);
        msg[LW_MSG_MAXLEN]='\0';
        fprintf(stderr, "%s\n", msg);
}
 
static void
default_debuglogger(int level, const char *fmt, va_list ap)
{
        char msg[LW_MSG_MAXLEN+1];
        if ( POSTGIS_DEBUG_LEVEL >= level )
        {
                /* Space pad the debug output */
                int i;
                for ( i = 0; i < level; i++ )
                        msg[i] = ' ';
                vsnprintf(msg+i, LW_MSG_MAXLEN-i, fmt, ap);
                msg[LW_MSG_MAXLEN]='\0';
                fprintf(stderr, "%s\n", msg);
        }
}
 
static void
default_errorreporter(const char *fmt, va_list ap)
{
        char msg[LW_MSG_MAXLEN+1];
        vsnprintf (msg, LW_MSG_MAXLEN, fmt, ap);
        msg[LW_MSG_MAXLEN]='\0';
        fprintf(stderr, "%s\n", msg);
        exit(1);
}
 
void
lwgeom_set_handlers(lwallocator allocator, lwreallocator reallocator,
                lwfreeor freeor, lwreporter errorreporter,
                lwreporter noticereporter) {
 
        if ( allocator ) lwalloc_var = allocator;
        if ( reallocator ) lwrealloc_var = reallocator;
        if ( freeor ) lwfree_var = freeor;
 
        if ( errorreporter ) lwerror_var = errorreporter;
        if ( noticereporter ) lwnotice_var = noticereporter;
}
 
void
lwgeom_set_debuglogger(lwdebuglogger debuglogger) {
 
        if ( debuglogger ) lwdebug_var = debuglogger;
}
 
void
lwnotice(const char *fmt, ...)
{
        va_list ap;
 
        va_start(ap, fmt);
 
        /* Call the supplied function */
        (*lwnotice_var)(fmt, ap);
 
        va_end(ap);
}
 
void
lwerror(const char *fmt, ...)
{
        va_list ap;
 
        va_start(ap, fmt);
 
        /* Call the supplied function */
        (*lwerror_var)(fmt, ap);
 
        va_end(ap);
}
 
void
lwdebug(int level, const char *fmt, ...)
{
        va_list ap;
 
        va_start(ap, fmt);
 
        /* Call the supplied function */
        (*lwdebug_var)(level, fmt, ap);
 
        va_end(ap);
}
 
 
 
const char*
lwtype_name(uint8_t type)
{
        if ( type > 15 )
        {
                /* assert(0); */
                return "Invalid type";
        }
        return lwgeomTypeName[(int ) type];
}
 
void *
lwalloc(size_t size)
{
        void *mem = lwalloc_var(size);
        LWDEBUGF(5, "lwalloc: %d@%p", size, mem);
        return mem;
}
 
void *
lwrealloc(void *mem, size_t size)
{
        LWDEBUGF(5, "lwrealloc: %d@%p", size, mem);
        return lwrealloc_var(mem, size);
}
 
void
lwfree(void *mem)
{
        lwfree_var(mem);
}
 
/*
 * Returns a new string which contains a maximum of maxlength characters starting
 * from startpos and finishing at endpos (0-based indexing). If the string is
 * truncated then the first or last characters are replaced by "..." as
 * appropriate.
 *
 * The caller should specify start or end truncation by setting the truncdirection
 * parameter as follows:
 *    0 - start truncation (i.e. characters are removed from the beginning)
 *    1 - end truncation (i.e. characters are removed from the end)
 */
 
char *lwmessage_truncate(char *str, int startpos, int endpos, int maxlength, int truncdirection)
{
        char *output;
        char *outstart;
 
        /* Allocate space for new string */
        output = lwalloc(maxlength + 4);
        output[0] = '\0';
 
        /* Start truncation */
        if (truncdirection == 0)
        {
                /* Calculate the start position */
                if (endpos - startpos < maxlength)
                {
                        outstart = str + startpos;
                        strncat(output, outstart, endpos - startpos + 1);
                }
                else
                {
                        if (maxlength >= 3)
                        {
                                /* Add "..." prefix */
                                outstart = str + endpos + 1 - maxlength + 3;
                                strncat(output, "...", 4);
                                strncat(output, outstart, maxlength - 3);
                        }
                        else
                        {
                                /* maxlength is too small; just output "..." */
                                strncat(output, "...", 4);
                        }
                }
        }
 
        /* End truncation */
        if (truncdirection == 1)
        {
                /* Calculate the end position */
                if (endpos - startpos < maxlength)
                {
                        outstart = str + startpos;
                        strncat(output, outstart, endpos - startpos + 1);
                }
                else
                {
                        if (maxlength >= 3)
                        {
                                /* Add "..." suffix */
                                outstart = str + startpos;
                                strncat(output, outstart, maxlength - 3);
                                strncat(output, "...", 4);
                        }
                        else
                        {
                                /* maxlength is too small; just output "..." */
                                strncat(output, "...", 4);
                        }
                }
        }
 
        return output;
}
 
 
char
getMachineEndian(void)
{
        static int endian_check_int = 1; /* don't modify this!!! */
 
        return *((char *) &endian_check_int); /* 0 = big endian | xdr,
                                               * 1 = little endian | ndr
                                               */
}
 
 
void
error_if_srid_mismatch(int srid1, int srid2)
{
        if ( srid1 != srid2 )
        {
                lwerror("Operation on mixed SRID geometries");
        }
}
 
int
clamp_srid(int srid)
{
        int newsrid = srid;
 
        if ( newsrid <= 0 ) {
                if ( newsrid != SRID_UNKNOWN ) {
                        newsrid = SRID_UNKNOWN;
                        lwnotice("SRID value %d converted to the officially unknown SRID value %d", srid, newsrid);
                }
        } else if ( srid > SRID_MAXIMUM ) {
    newsrid = SRID_USER_MAXIMUM + 1 +
      /* -1 is to reduce likelyhood of clashes */
      /* NOTE: must match implementation in postgis_restore.pl */
      ( srid % ( SRID_MAXIMUM - SRID_USER_MAXIMUM - 1 ) );
                lwnotice("SRID value %d > SRID_MAXIMUM converted to %d", srid, newsrid);
        }
 
        return newsrid;
}