From f3029bb3cfed9e9727ef161ebaaa1e358ef72025 Mon Sep 17 00:00:00 2001
From: Gareth Evans <gareth.evans@contextis.co.uk>
Date: Sat, 4 Mar 2017 19:35:03 +0000
Subject: [PATCH] Detect and handle errors in topo data

---
 inputs.cc | 22 ++++++++++++++--------
 inputs.hh |  4 ++--
 main.cc   | 14 +++++++++++---
 3 files changed, 27 insertions(+), 13 deletions(-)

diff --git a/inputs.cc b/inputs.cc
index 92312da..a18d7a8 100644
--- a/inputs.cc
+++ b/inputs.cc
@@ -364,8 +364,8 @@ int LoadSDF_SDF(char *name)
 
 	/* Parse filename for minimum latitude and longitude values */
 
-		sscanf(sdf_file, "%d:%d:%d:%d", &minlat, &maxlat, &minlon,
-		       &maxlon);
+	sscanf(sdf_file, "%d:%d:%d:%d", &minlat, &maxlat, &minlon,
+	       &maxlon);
 	
 
 	sdf_file[x] = '.';
@@ -533,7 +533,7 @@ int LoadSDF_SDF(char *name)
 		return 0;
 }
 
-char LoadSDF(char *name)
+int LoadSDF(char *name)
 {
 	/* This function loads the requested SDF file from the filesystem.
 	   It first tries to invoke the LoadSDF_SDF() function to load an
@@ -555,8 +555,8 @@ char LoadSDF(char *name)
 	if ( return_value == 0 || return_value < 0 ) {
 
 
-			sscanf(name, "%d:%d:%d:%d", &minlat, &maxlat, &minlon,
-			       &maxlon);
+		sscanf(name, "%d:%d:%d:%d", &minlat, &maxlat, &minlon,
+		       &maxlon);
 		
 		/* Is it already in memory? */
 
@@ -1458,12 +1458,13 @@ int LoadDBMColors(struct site xmtr)
 	return 0;
 }
 
-void LoadTopoData(int max_lon, int min_lon, int max_lat, int min_lat)
+int LoadTopoData(int max_lon, int min_lon, int max_lat, int min_lat)
 {
 	/* This function loads the SDF files required
 	   to cover the limits of the region specified. */
 
 	int x, y, width, ymin, ymax;
+	int success;
 
 	width = ReduceAngle(max_lon - min_lon);
 
@@ -1495,7 +1496,9 @@ void LoadTopoData(int max_lon, int min_lon, int max_lat, int min_lat)
 						snprintf(string, 16,
 							 "%d:%d:%d:%d", x,
 							 x + 1, ymin, ymax);
-				LoadSDF(string);
+				if( (success = LoadSDF(string)) < 0 ){
+					return -success;
+				}
 			}
 	}
 
@@ -1526,9 +1529,12 @@ void LoadTopoData(int max_lon, int min_lon, int max_lat, int min_lat)
 						snprintf(string, 16,
 							 "%d:%d:%d:%d", x,
 							 x + 1, ymin, ymax);
-				LoadSDF(string);
+				if( (success = LoadSDF(string)) < 0 ){
+					return -success;
+				}
 			}
 	}
+	return 0;
 }
 
 void LoadUDT(char *filename)
diff --git a/inputs.hh b/inputs.hh
index d15a87c..81addde 100644
--- a/inputs.hh
+++ b/inputs.hh
@@ -4,12 +4,12 @@
 #include "common.h"
 
 int LoadSDF_SDF(char *name, int winfiles);
-char LoadSDF(char *name, int winfiles);
+int LoadSDF(char *name, int winfiles);
 int LoadPAT(char *az_filename, char *el_filename);
 int LoadSignalColors(struct site xmtr);
 int LoadLossColors(struct site xmtr);
 int LoadDBMColors(struct site xmtr);
-void LoadTopoData(int max_lon, int min_lon, int max_lat, int min_lat);
+int LoadTopoData(int max_lon, int min_lon, int max_lat, int min_lat);
 void LoadUDT(char *filename);
 int loadLIDAR(char *filename);
 int loadClutter(char *filename, double radius, struct site tx);
diff --git a/main.cc b/main.cc
index c96b966..07ff094 100644
--- a/main.cc
+++ b/main.cc
@@ -1708,9 +1708,13 @@ int main(int argc, char *argv[])
 	
 	}else{
 		// DEM first
-		LoadTopoData(max_lon, min_lon, max_lat, min_lat);
+		if( (result = LoadTopoData(max_lon, min_lon, max_lat, min_lat)) != 0 ){
+			// This only fails on errors loading SDF tiles
+			fprintf(stderr, "Error loading topo data\n");
+			return result;
+		}
 
-			if (area_mode || topomap) {
+		if (area_mode || topomap) {
 			for (z = 0; z < txsites && z < max_txsites; z++) {
 				/* "Ball park" estimates used to load any additional
 				   SDF files required to conduct this analysis. */
@@ -1793,7 +1797,11 @@ int main(int argc, char *argv[])
 
 			/* Load any additional SDF files, if required */
 
-			LoadTopoData(max_lon, min_lon, max_lat, min_lat);
+			if( (result = LoadTopoData(max_lon, min_lon, max_lat, min_lat)) != 0 ){
+				// This only fails on errors loading SDF tiles
+				fprintf(stderr, "Error loading topo data\n");
+				return result;
+			}
 		}
 		ppd=(double)ippd;
 		yppd=ppd;