From 16e500b65005df5a9f4c8f8d676210a9217bcd03 Mon Sep 17 00:00:00 2001
From: Sandro Santilli <strk@keybit.net>
Date: Fri, 10 Feb 2012 16:53:15 +0000
Subject: [PATCH] Clamp SRID valuesu > SRID_MAXIMUM to fall in the reserved
 range (#1505)

The reserved range is SRID_USER_MAXIMUM+1 to SRID_MAXIMUM.
Core takes care of typmod clamping, postgis_restore.pl takes care
of clamping table definition and spatial_ref_sys entries.

git-svn-id: http://svn.osgeo.org/postgis/trunk@9145 b70326c6-7e19-0410-871a-916f4a2858ee
---
 liblwgeom/lwutil.c       | 19 +++++++++-----
 utils/postgis_restore.pl | 55 ++++++++++++++++++++++++++++++++++++++--
 2 files changed, 65 insertions(+), 9 deletions(-)

diff --git a/liblwgeom/lwutil.c b/liblwgeom/lwutil.c
index a9bcd8a5f..f09de91fc 100644
--- a/liblwgeom/lwutil.c
+++ b/liblwgeom/lwutil.c
@@ -372,15 +372,20 @@ error_if_srid_mismatch(int srid1, int srid2)
 int
 clamp_srid(int srid)
 {
-	if ( srid <= 0 ) {
-		if ( srid != SRID_UNKNOWN ) {
-			lwnotice("SRID value %d converted to the officially unknown SRID value %d", srid, SRID_UNKNOWN);
-			srid = SRID_UNKNOWN;
+	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 ) {
-		/* should this be a NOTICE instead ? */
-		lwerror("SRID value %d > SRID_MAXIMUM (%d)",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 srid;
+	return newsrid;
 }
diff --git a/utils/postgis_restore.pl b/utils/postgis_restore.pl
index 0b92e49ef..3c09da6ad 100755
--- a/utils/postgis_restore.pl
+++ b/utils/postgis_restore.pl
@@ -51,6 +51,11 @@ Usage:	$me [-v] <dumpfile>
 
 my $DEBUG = 0;
 
+# NOTE: the SRID limits here are being discussed:
+# http://postgis.refractions.net/pipermail/postgis-devel/2012-February/018463.html
+my $SRID_MAXIMUM = 999999;
+my $SRID_USER_MAXIMUM = 998999; 
+
 if ( @ARGV && $ARGV[0] eq '-v' ) {
   $DEBUG = 1;
   shift(@ARGV);
@@ -208,7 +213,13 @@ while( my $l = <INPUT> ) {
       }
       if ( $subline =~ /CONSTRAINT enforce_srid_/i ) {
         $subline =~ s/\.srid\(/.st_srid(/;
-        $subline =~ s/\(-1\)/(0)/;
+        if ( $subline =~ /=\s\(?([-0-9][0-9]*)\)/ ) {
+          my $oldsrid = $1;
+          my $newsrid = clamp_srid($oldsrid);
+          $subline =~ s/=\s*(\(?)[-0-9][0-9]*/= $1$newsrid/;
+        } else {
+          print STDERR "WARNING: could not find SRID value in: $subline";
+        }
       }
       push(@sublines, $subline);
       last if $subline =~ /;[\t ]*$/;
@@ -217,6 +228,23 @@ while( my $l = <INPUT> ) {
     next;
   }
 
+  # Clamp SRIDS in spatial_ref_sys
+  elsif ( $l =~ /COPY spatial_ref_sys /)
+  {
+    print STDOUT $l;
+    while( my $subline = <INPUT>)
+    {
+      if ( $subline =~ /([0-9]*)\t/ ) {
+        my $oldsrid = $1;
+          my $newsrid = clamp_srid($oldsrid);
+          $subline =~ s/^[0-9]*\t/${newsrid}\t/;
+      }
+      print STDOUT $subline;
+      last if $subline =~ /^\.$/;
+    }
+    next;
+  }
+
   print STDOUT $l;
 
 }
@@ -251,7 +279,7 @@ print STDOUT "DROP TABLE _pgis_restore_spatial_ref_sys;\n";
 # but you'd still have your data
 print STDOUT "ALTER TABLE spatial_ref_sys ADD constraint " 
            . "spatial_ref_sys_srid_check check "
-           . "( srid > 0 and srid < 999000 ) ;\n";
+           . "( srid > 0 and srid < " . ($SRID_USER_MAXIMUM+1) ." ) ;\n";
 
 
 print STDERR "Done.\n";
@@ -333,6 +361,29 @@ canonicalize_typename
 	return $arg;
 }
 
+# Change SRID to be within allowed ranges
+sub
+clamp_srid
+{
+  my $oldsrid = shift;
+  my $newsrid = $oldsrid;
+
+  if ( $oldsrid < 0 ) {
+    $newsrid = 0;
+  } elsif ( $oldsrid > $SRID_MAXIMUM ) {
+    $newsrid = $SRID_USER_MAXIMUM + 1 +
+      # -1 is to reduce likelyhood of clashes 
+      # NOTE: must match core implementation (lwutil.c)
+      ( $oldsrid % ( $SRID_MAXIMUM - $SRID_USER_MAXIMUM - 1 ) );
+  }
+
+  if ( $oldsrid != $newsrid ) {
+    printf STDERR "  WARNING: SRID value $oldsrid converted to $newsrid\n";
+  }
+
+  return $newsrid;
+}
+
 
 ######################################################################
 # Here are all the signatures we want to skip.
-- 
2.50.1