Merge pull request #857 from kbevers/return-error-instead-of-zeros

Make sure that transient errors are returned correctly

3 files changed, 72 insertions, 6 deletions

diff --git a/src/pj_fwd.c b/src/pj_fwd.c
index b2e6afd5..ef05962d 100644
--- a/src/pj_fwd.c
+++ b/src/pj_fwd.c
@@ -174,11 +174,22 @@ static PJ_COORD fwd_finalize (PJ *P, PJ_COORD coo) {
 }
 
 
+static PJ_COORD error_or_coord(PJ *P, PJ_COORD coord, int last_errno) {
+    if (proj_errno(P))
+        return proj_coord_error();
+
+    proj_errno_restore(P, last_errno);
+    return coord;
+}
+
 
 XY pj_fwd(LP lp, PJ *P) {
+    int last_errno;
     PJ_COORD coo = {{0,0,0,0}};
     coo.lp = lp;
 
+    last_errno = proj_errno_reset(P);
+
     if (!P->skip_fwd_prepare)
         coo = fwd_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
@@ -200,15 +211,19 @@ XY pj_fwd(LP lp, PJ *P) {
 
     if (!P->skip_fwd_finalize)
         coo = fwd_finalize (P, coo);
-    return coo.xy;
+
+    return error_or_coord(P, coo, last_errno).xy;
 }
 
 
 
 XYZ pj_fwd3d(LPZ lpz, PJ *P) {
+    int last_errno;
     PJ_COORD coo = {{0,0,0,0}};
     coo.lpz = lpz;
 
+    last_errno = proj_errno_reset(P);
+
     if (!P->skip_fwd_prepare)
         coo = fwd_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
@@ -230,12 +245,15 @@ XYZ pj_fwd3d(LPZ lpz, PJ *P) {
 
     if (!P->skip_fwd_finalize)
         coo = fwd_finalize (P, coo);
-    return coo.xyz;
+
+    return error_or_coord(P, coo, last_errno).xyz;
 }
 
 
 
 PJ_COORD pj_fwd4d (PJ_COORD coo, PJ *P) {
+    int last_errno = proj_errno_reset(P);
+
     if (!P->skip_fwd_prepare)
         coo = fwd_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
@@ -257,5 +275,6 @@ PJ_COORD pj_fwd4d (PJ_COORD coo, PJ *P) {
 
     if (!P->skip_fwd_finalize)
         coo = fwd_finalize (P, coo);
-    return coo;
+
+    return error_or_coord(P, coo, last_errno);
 }
diff --git a/src/pj_inv.c b/src/pj_inv.c
index 7f1889f3..f2901ca0 100644
--- a/src/pj_inv.c
+++ b/src/pj_inv.c
@@ -172,11 +172,22 @@ static PJ_COORD inv_finalize (PJ *P, PJ_COORD coo) {
 }
 
 
+static PJ_COORD error_or_coord(PJ *P, PJ_COORD coord, int last_errno) {
+    if (proj_errno(P))
+        return proj_coord_error();
+
+    proj_errno_restore(P, last_errno);
+    return coord;
+}
+
 
 LP pj_inv(XY xy, PJ *P) {
+    int last_errno;
     PJ_COORD coo = {{0,0,0,0}};
     coo.xy = xy;
 
+    last_errno = proj_errno_reset(P);
+
     if (!P->skip_inv_prepare)
         coo = inv_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
@@ -198,15 +209,19 @@ LP pj_inv(XY xy, PJ *P) {
 
     if (!P->skip_inv_finalize)
         coo = inv_finalize (P, coo);
-    return coo.lp;
+
+    return error_or_coord(P, coo, last_errno).lp;
 }
 
 
 
 LPZ pj_inv3d (XYZ xyz, PJ *P) {
+    int last_errno;
     PJ_COORD coo = {{0,0,0,0}};
     coo.xyz = xyz;
 
+    last_errno = proj_errno_reset(P);
+
     if (!P->skip_inv_prepare)
         coo = inv_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
@@ -228,12 +243,15 @@ LPZ pj_inv3d (XYZ xyz, PJ *P) {
 
     if (!P->skip_inv_finalize)
         coo = inv_finalize (P, coo);
-    return coo.lpz;
+
+    return error_or_coord(P, coo, last_errno).lpz;
 }
 
 
 
 PJ_COORD pj_inv4d (PJ_COORD coo, PJ *P) {
+    int last_errno = proj_errno_reset(P);
+
     if (!P->skip_inv_prepare)
         coo = inv_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
@@ -255,5 +273,6 @@ PJ_COORD pj_inv4d (PJ_COORD coo, PJ *P) {
 
     if (!P->skip_inv_finalize)
         coo = inv_finalize (P, coo);
-    return coo;
+
+    return error_or_coord(P, coo, last_errno);
 }
diff --git a/test/gie/4D-API_cs2cs-style.gie b/test/gie/4D-API_cs2cs-style.gie
index 66da0633..b7c37c83 100644
--- a/test/gie/4D-API_cs2cs-style.gie
+++ b/test/gie/4D-API_cs2cs-style.gie
@@ -186,4 +186,32 @@ tolerance 20 cm
 accept    7.438632495 46.951082877
 expect    2600000.0  1200000.0
 -------------------------------------------------------------------------------
+
+-------------------------------------------------------------------------------
+Make sure that transient errors are returned correctly.
+-------------------------------------------------------------------------------
+operation +proj=geos +lon_0=0.00 +lat_0=0.00 +a=6378169.00 +b=6356583.80 +h=35785831.0
+-------------------------------------------------------------------------------
+accept  85.05493299 46.5261074
+expect  failure
+
+accept  85.05493299 46.5261074 0
+expect  failure
+
+accept  85.05493299 46.5261074 0 0
+expect  failure
+
+-------------------------------------------------------------------------------
+Test that Google's Web Mercator works as intended (see #834 for details).
+-------------------------------------------------------------------------------
+operation   proj=pipeline step init=epsg:26915 inv step init=epsg:3857
+-------------------------------------------------------------------------------
+tolerance   20 cm
+accept      487147.594520173    4934316.46263998
+expect      -10370728.80        5552839.74
+
+accept      487147.594520173    4934316.46263998    0
+expect      -10370728.80        5552839.74          0
+-------------------------------------------------------------------------------
+
 </gie>