ECC-1813: GRIB2: Sub-hourly: Set step units without step

examples/C/large_grib1.c

@@ -14,7 +14,7 @@
 #include "eccodes.h"
 
 /* See JIRA issue GRIB-361 */
-int main()
+int main(void)
 {
     const int ni = 2880;
     const int nj = 2880;

src/grib_accessor_class_g2end_step.cc

@@ -262,9 +262,13 @@ static int unpack_one_time_range_long_(grib_accessor* a, long* val, size_t* len)
     }
     if (add_time_range) {
         *val = start_step_value + time_range_value;
+        if ((err = grib_set_long_internal(h, "endStepUnit", step_units)) != GRIB_SUCCESS)
+            return err;
     }
     else {
         *val = start_step_value;
+        if ((err = grib_set_long_internal(h, "endStepUnit", step_units)) != GRIB_SUCCESS)
+            return err;
     }
 
     return GRIB_SUCCESS;
@@ -310,9 +314,13 @@ static int unpack_one_time_range_double_(grib_accessor* a, double *val , size_t*
     }
     if (add_time_range) {
         *val = (start_step + time_range).value<double>(eccodes::Unit(step_units));
+        if ((err = grib_set_long_internal(h, "endStepUnit", step_units)) != GRIB_SUCCESS)
+            return err;
     }
     else {
         *val = start_step.value<double>(eccodes::Unit(start_step_unit));
+        if ((err = grib_set_long_internal(h, "endStepUnit", start_step_unit)) != GRIB_SUCCESS)
+            return err;
     }
 
     return GRIB_SUCCESS;
@@ -441,14 +449,19 @@ static int unpack_long(grib_accessor* a, long* val, size_t* len)
     grib_handle* h = grib_handle_of_accessor(a);
     int ret = 0;
     long start_step_value;
+    long start_step_unit;
     long numberOfTimeRange;
 
     if ((ret = grib_get_long_internal(h, self->start_step_value, &start_step_value)))
         return ret;
+    if ((ret = grib_get_long_internal(h, "startStepUnit", &start_step_unit)))
+        return ret;
 
     /* point in time */
     if (self->year == NULL) {
         *val = start_step_value;
+        if ((ret = grib_set_long_internal(h, "endStepUnit", start_step_unit)))
+            return ret;
         return 0;
     }
 
@@ -479,14 +492,19 @@ static int unpack_double(grib_accessor* a, double* val, size_t* len)
     grib_handle* h = grib_handle_of_accessor(a);
     int ret = 0;
     long start_step_value;
+    long start_step_unit;
     long numberOfTimeRange;
 
     if ((ret = grib_get_long_internal(h, self->start_step_value, &start_step_value)))
         return ret;
+    if ((ret = grib_get_long_internal(h, "startStepUnit", &start_step_unit)))
+        return ret;
 
     /* point in time */
     if (self->year == NULL) {
         *val = start_step_value;
+        if ((ret = grib_set_long_internal(h, "endStepUnit", start_step_unit)))
+            return ret;
         return 0;
     }
 
@@ -542,7 +560,8 @@ static int pack_long_(grib_accessor* a, const long end_step_value, const long en
 
     /*point in time */
     if (self->year == NULL) {
-        err = grib_set_long_internal(h, "startStepUnit", end_step.unit().value<long>());
+        if ((err = grib_set_long_internal(h, "startStepUnit", end_step.unit().value<long>())) != GRIB_SUCCESS)
+            return err;
         err = grib_set_long_internal(h, self->start_step_value, end_step.value<long>());
         return err;
     }

src/grib_accessor_class_optimal_step_units.cc

@@ -178,6 +178,12 @@ static int pack_long(grib_accessor* a, const long* val, size_t* len)
     grib_handle* h = grib_handle_of_accessor(a);
     grib_accessor_optimal_step_units* self = (grib_accessor_optimal_step_units*)a;
 
+    long start_step = 0;
+    long start_step_unit = 0;
+    long end_step = 0;
+    long end_step_unit = 0;
+    int ret;
+
     auto supported_units = eccodes::Unit::list_supported_units();
     try {
         eccodes::Unit unit{*val}; // throws if not supported
@@ -198,10 +204,42 @@ static int pack_long(grib_accessor* a, const long* val, size_t* len)
         return GRIB_INVALID_ARGUMENT;
     }
 
-    int ret;
+    // ECC-1813: When the stepUnits key is used without specifying a value, as in the command
+    // "grib-set -s stepUnits=m in.grib out.grib", the following code initiates an indirect update
+    // of the low-level keys: forecastTime,indicatorOfUnitOfTimeRange,indicatorOfUnitForTimeRange,lengthOfTimeRange
+
     self->overwriteStepUnits = *val;
-    if ((ret = grib_set_long_internal(h, "forceStepUnits", *val)) != GRIB_SUCCESS) {
+    if ((ret = grib_set_long_internal(h, "forceStepUnits", *val)) != GRIB_SUCCESS)
+        return ret;
+
+    if ((ret = grib_get_long_internal(h, "startStep", &start_step)) != GRIB_SUCCESS)
+        return ret;
+    if ((ret = grib_get_long_internal(h, "startStepUnit", &start_step_unit)) != GRIB_SUCCESS)
+        return ret;
+    if ((ret = grib_get_long_internal(h, "endStep", &end_step)) != GRIB_SUCCESS)
         return ret;
+    if ((ret = grib_get_long_internal(h, "endStepUnit", &end_step_unit)) != GRIB_SUCCESS)
+        return ret;
+
+    try {
+        eccodes::Step start{start_step, start_step_unit};
+        start.set_unit(*val);
+        eccodes::Step end{end_step, end_step_unit};
+        end.set_unit(*val);
+
+        if ((ret = grib_set_long_internal(h, "startStepUnit", start.unit().value<long>())) != GRIB_SUCCESS)
+            return ret;
+        if ((ret = grib_set_long_internal(h, "startStep", start.value<long>())) != GRIB_SUCCESS)
+            return ret;
+        if ((ret = grib_set_long_internal(h, "endStepUnit", end.unit().value<long>())) != GRIB_SUCCESS)
+            return ret;
+        if ((ret = grib_set_long_internal(h, "endStep", end.value<long>())) != GRIB_SUCCESS)
+            return ret;
+    }
+    catch (std::exception& e) {
+        std::string msg = std::string{"Failed to convert steps to: "} + std::to_string(*val) + " (" + e.what() + ")";
+        grib_context_log(a->context, GRIB_LOG_ERROR, "%s", msg.c_str());
+        return GRIB_INTERNAL_ERROR;
     }
 
     return GRIB_SUCCESS;