Comparison of accessors

src/eccodes_prototypes.h

@@ -154,6 +154,7 @@ int grib_nearest_smaller_value(grib_accessor* a, double val, double* nearest);
 size_t grib_preferred_size(grib_accessor* a, int from_handle);
 grib_accessor* grib_next_accessor(grib_accessor* a);
 void grib_resize(grib_accessor* a, size_t new_size);
+int grib_compare_accessors(grib_accessor* a1, grib_accessor* a2, int compare_flags);
 int grib_accessor_add_attribute(grib_accessor* a, grib_accessor* attr, int nest_if_clash);
 int grib_accessor_replace_attribute(grib_accessor* a, grib_accessor* attr);
 int grib_accessor_delete_attribute(grib_accessor* a, const char* name);
@@ -1277,6 +1278,7 @@ void grib_print_values(const char* title, grib_values* values);
 int grib_values_check(grib_handle* h, grib_values* values, int count);
 int grib_key_equal(grib_handle* h1, grib_handle* h2, const char* key, int type, int* err);
 int codes_copy_key(grib_handle* h1, grib_handle* h2, const char* key, int type);
+int codes_compare_key(grib_handle* h1, grib_handle* h2, const char* key, int compare_flags);
 
 /* grib_errors.cc*/
 const char* grib_get_error_message(int code);

src/grib_accessor.cc

@@ -652,50 +652,48 @@ void grib_resize(grib_accessor* a, size_t new_size)
     return;
 }
 
-// int grib_compare_accessors(grib_accessor* a1, grib_accessor* a2, int compare_flags)
-// {
-//     int ret                 = 0;
-//     long type1              = 0;
-//     long type2              = 0;
-//     int type_mismatch       = 0;
-//     grib_accessor_class* c1 = NULL;
-
-//     if ((compare_flags & GRIB_COMPARE_NAMES) && grib_inline_strcmp(a1->name, a2->name))
-//         return GRIB_NAME_MISMATCH;
-
-//     if (compare_flags & GRIB_COMPARE_TYPES) {
-//         type1 = grib_accessor_get_native_type(a1);
-//         type2 = grib_accessor_get_native_type(a2);
-
-//         type_mismatch = type1 != type2 ? 1 : 0;
-//     }
-
-//     ret = GRIB_UNABLE_TO_COMPARE_ACCESSORS;
-//     c1  = a1->cclass;
-//     while (c1) {
-//         if (c1->compare) {
-//             ret = c1->compare(a1, a2);
-//             break;
-//         }
-//         c1 = c1->super ? *(c1->super) : NULL;
-//     }
-
-//     if (ret == GRIB_VALUE_MISMATCH && type_mismatch)
-//         ret = GRIB_TYPE_AND_VALUE_MISMATCH;
-
-//     return ret;
-// }
-
-/*
-int grib_accessor_clear_attributes(grib_accessor* a)
+int grib_compare_accessors(grib_accessor* a1, grib_accessor* a2, int compare_flags)
 {
-    int id;
-    for (id=0;id<MAX_ACCESSOR_ATTRIBUTES;id++) {
-        a->attributes[id]=NULL;
+    int ret                 = 0;
+    long type1              = 0;
+    long type2              = 0;
+    int type_mismatch       = 0;
+    grib_accessor_class* c1 = NULL;
+
+    if ((compare_flags & GRIB_COMPARE_NAMES) && grib_inline_strcmp(a1->name, a2->name))
+        return GRIB_NAME_MISMATCH;
+
+    if (compare_flags & GRIB_COMPARE_TYPES) {
+        type1 = grib_accessor_get_native_type(a1);
+        type2 = grib_accessor_get_native_type(a2);
+
+        type_mismatch = type1 != type2 ? 1 : 0;
     }
-    return 0;
+
+    ret = GRIB_UNABLE_TO_COMPARE_ACCESSORS;
+    c1  = a1->cclass;
+    while (c1) {
+        if (c1->compare) {
+            ret = c1->compare(a1, a2);
+            break;
+        }
+        c1 = c1->super ? *(c1->super) : NULL;
+    }
+
+    if (ret == GRIB_VALUE_MISMATCH && type_mismatch)
+        ret = GRIB_TYPE_AND_VALUE_MISMATCH;
+
+    return ret;
 }
- */
+
+// int grib_accessor_clear_attributes(grib_accessor* a)
+// {
+//     int id;
+//     for (id=0;id<MAX_ACCESSOR_ATTRIBUTES;id++) {
+//         a->attributes[id]=NULL;
+//     }
+//     return 0;
+// }
 
 int grib_accessor_add_attribute(grib_accessor* a, grib_accessor* attr, int nest_if_clash)
 {

src/grib_accessor_class_ascii.cc

@@ -250,19 +250,8 @@ static int compare(grib_accessor* a, grib_accessor* b)
     char* bval = 0;
     int err    = 0;
 
-    size_t alen = 0;
-    size_t blen = 0;
-    long count  = 0;
-
-    err = grib_value_count(a, &count);
-    if (err)
-        return err;
-    alen = count;
-
-    err = grib_value_count(b, &count);
-    if (err)
-        return err;
-    blen = count;
+    size_t alen = a->length+1;
+    size_t blen = b->length+1;
 
     if (alen != blen)
         return GRIB_COUNT_MISMATCH;
@@ -270,11 +259,13 @@ static int compare(grib_accessor* a, grib_accessor* b)
     aval = (char*)grib_context_malloc(a->context, alen * sizeof(char));
     bval = (char*)grib_context_malloc(b->context, blen * sizeof(char));
 
-    grib_unpack_string(a, aval, &alen);
-    grib_unpack_string(b, bval, &blen);
+    err = grib_unpack_string(a, aval, &alen);
+    if (err) return err;
+    err = grib_unpack_string(b, bval, &blen);
+    if (err) return err;
 
     retval = GRIB_SUCCESS;
-    if (strcmp(aval, bval))
+    if (!STR_EQUAL(aval, bval))
         retval = GRIB_STRING_VALUE_MISMATCH;
 
     grib_context_free(a->context, aval);

src/grib_value.cc

@@ -2083,3 +2083,19 @@ int codes_copy_key(grib_handle* h1, grib_handle* h2, const char* key, int type)
             return GRIB_INVALID_TYPE;
     }
 }
+
+int codes_compare_key(grib_handle* h1, grib_handle* h2, const char* key, int compare_flags)
+{
+    grib_accessor* a1 = grib_find_accessor(h1, key);
+    if (!a1) {
+        grib_context_log(h1->context, GRIB_LOG_ERROR, "Key %s not found in first message", key);
+        return GRIB_NOT_FOUND;
+    }
+    grib_accessor* a2 = grib_find_accessor(h2, key);
+    if (!a2) {
+        grib_context_log(h1->context, GRIB_LOG_ERROR, "Key %s not found in second message", key);
+        return GRIB_NOT_FOUND;
+    }
+
+    return grib_compare_accessors(a1, a2, GRIB_COMPARE_TYPES);
+}

tests/CMakeLists.txt

@@ -45,6 +45,7 @@ list(APPEND test_c_bins
     bufr_coordinate_descriptors
     codes_new_from_samples
     codes_set_samples_path
+    codes_compare_keys
     grib_sh_ieee64
     grib_ieee
     grib_set_bytes

tests/codes_compare_keys.cc

@@ -0,0 +1,57 @@
+/*
+ * (C) Copyright 2005- ECMWF.
+ *
+ * This software is licensed under the terms of the Apache Licence Version 2.0
+ * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
+ * virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
+ */
+
+#include "grib_api_internal.h"
+
+int main(int argc, char* argv[])
+{
+    FILE* f1       = NULL;
+    FILE* f2       = NULL;
+    grib_handle* h1 = NULL;
+    grib_handle* h2 = NULL;
+    int err       = 0;
+    int failed    = 0;
+
+    Assert(argc == 3);
+    f1 = fopen(argv[1], "rb");
+    f2 = fopen(argv[2], "rb");
+    Assert(f1 && f2);
+
+    while ((h1 = grib_handle_new_from_file(0, f1, &err)) != NULL && (h2 = grib_handle_new_from_file(0, f2, &err)) != NULL) {
+        grib_keys_iterator* kiter = NULL;
+
+        /* Use namespace of NULL to get ALL keys */
+        /* Set flags to 0 to not filter any keys */
+        //kiter = grib_keys_iterator_new(h1, /*flags=*/0, /*namespace=*/NULL);
+        kiter = grib_keys_iterator_new(h1, /*flags=*/GRIB_KEYS_ITERATOR_SKIP_COMPUTED, /*namespace=*/NULL);
+        Assert(kiter);
+
+        while (grib_keys_iterator_next(kiter)) {
+            const char* name = grib_keys_iterator_get_name(kiter);
+            Assert(name);
+            //printf("Comparing key '%s' ...\n", name);
+            err = codes_compare_key(h1, h2, name, 0);
+            if (err) {
+                printf("key: %s  (%s)\n", name, grib_get_error_message(err));
+                failed = 1;
+            }
+        }
+
+        grib_keys_iterator_delete(kiter);
+        grib_handle_delete(h1);
+        grib_handle_delete(h2);
+    }
+    fclose(f1);
+    fclose(f2);
+    if (failed) {
+        fprintf(stderr, "\nComparison failed: One or more keys different\n");
+    }
+    return err;
+}