Interface for mapping JSON configuration objects to C structures.

src/nxt_clang.h

@@ -173,6 +173,10 @@ nxt_container_of(p, type, field)                                              \
     (type *) ((u_char *) (p) - offsetof(type, field))
 
 
+#define nxt_pointer_to(p, offset)                                             \
+    ((void *) ((char *) (p) + (offset)))
+
+
 #define nxt_value_at(type, p, offset)                                         \
     *(type *) ((u_char *) p + offset)
 

src/nxt_conf.h

@@ -13,6 +13,26 @@ typedef struct nxt_conf_json_value_s  nxt_conf_json_value_t;
 typedef struct nxt_conf_json_op_s     nxt_conf_json_op_t;
 
 
+typedef enum {
+    NXT_CONF_JSON_MAP_INT8,
+    NXT_CONF_JSON_MAP_INT32,
+    NXT_CONF_JSON_MAP_INT64,
+    NXT_CONF_JSON_MAP_INT,
+    NXT_CONF_JSON_MAP_SIZE,
+    NXT_CONF_JSON_MAP_OFF,
+    NXT_CONF_JSON_MAP_DOUBLE,
+    NXT_CONF_JSON_MAP_STR,
+    NXT_CONF_JSON_MAP_PTR,
+} nxt_conf_json_map_type_t;
+
+
+typedef struct {
+    nxt_str_t                 name;
+    nxt_conf_json_map_type_t  type;
+    size_t                    offset;
+} nxt_conf_json_object_map_t;
+
+
 typedef struct {
     uint32_t                  level;
     uint8_t                   more_space;  /* 1 bit. */
@@ -24,6 +44,9 @@ nxt_conf_json_value_t *nxt_conf_json_get_value(nxt_conf_json_value_t *value,
 nxt_conf_json_value_t *nxt_conf_json_object_get_member(
     nxt_conf_json_value_t *value, nxt_str_t *name, uint32_t *index);
 
+nxt_int_t nxt_conf_json_object_map(nxt_conf_json_value_t *value,
+    nxt_conf_json_object_map_t *map, void *data);
+
 nxt_int_t nxt_conf_json_op_compile(nxt_mp_t *mp, nxt_conf_json_op_t **ops,
     nxt_conf_json_value_t *root, nxt_str_t *path,
     nxt_conf_json_value_t *value);

src/nxt_conf_json.c

@@ -44,7 +44,7 @@ struct nxt_conf_json_value_s {
     union {
         uint32_t                boolean;  /* 1 bit. */
         int64_t                 integer;
-     /* double                  number; */
+        double                  number;
         u_char                  str[1 + NXT_CONF_JSON_STR_SIZE];
         nxt_str_t               *string;
         nxt_conf_json_array_t   *array;
@@ -252,6 +252,124 @@ nxt_conf_json_object_get_member(nxt_conf_json_value_t *value, nxt_str_t *name,
 }
 
 
+nxt_int_t
+nxt_conf_json_object_map(nxt_conf_json_value_t *value,
+    nxt_conf_json_object_map_t *map, void *data)
+{
+    nxt_uint_t             i;
+    nxt_conf_json_value_t  *v;
+
+    union {
+        uint8_t    ui8;
+        int32_t    i32;
+        int64_t    i64;
+        nxt_int_t  i;
+        ssize_t    size;
+        off_t      off;
+        double     dbl;
+        nxt_str_t  str;
+        void       *v;
+    } *ptr;
+
+    for (i = 0; map[i].name.length != 0; i++) {
+
+        v = nxt_conf_json_object_get_member(value, &map[i].name, NULL);
+
+        if (v == NULL || v->type == NXT_CONF_JSON_NULL) {
+            continue;
+        }
+
+        ptr = nxt_pointer_to(data, map[i].offset);
+
+        switch (map[i].type) {
+
+        case NXT_CONF_JSON_MAP_INT8:
+
+            if (v->type != NXT_CONF_JSON_BOOLEAN) {
+                return NXT_ERROR;
+            }
+
+            ptr->ui8 = v->u.boolean;
+
+            break;
+
+        case NXT_CONF_JSON_MAP_INT32:
+        case NXT_CONF_JSON_MAP_INT64:
+        case NXT_CONF_JSON_MAP_INT:
+        case NXT_CONF_JSON_MAP_SIZE:
+        case NXT_CONF_JSON_MAP_OFF:
+
+            if (v->type != NXT_CONF_JSON_INTEGER) {
+                return NXT_ERROR;
+            }
+
+            switch (map[i].type) {
+
+            case NXT_CONF_JSON_MAP_INT32:
+                ptr->ui8 = v->u.integer;
+                break;
+
+            case NXT_CONF_JSON_MAP_INT64:
+                ptr->i64 = v->u.integer;
+                break;
+
+            case NXT_CONF_JSON_MAP_INT:
+                ptr->i = v->u.integer;
+                break;
+
+            case NXT_CONF_JSON_MAP_SIZE:
+                ptr->size = v->u.integer;
+                break;
+
+            case NXT_CONF_JSON_MAP_OFF:
+                ptr->off = v->u.integer;
+                break;
+
+            default:
+                nxt_unreachable();
+            }
+
+            break;
+
+        case NXT_CONF_JSON_MAP_DOUBLE:
+
+            if (v->type == NXT_CONF_JSON_NUMBER) {
+                ptr->dbl = v->u.number;
+
+            } else if (v->type == NXT_CONF_JSON_INTEGER) {
+                ptr->dbl = v->u.integer;
+
+            } else {
+                return NXT_ERROR;
+            }
+
+            break;
+
+        case NXT_CONF_JSON_MAP_STR:
+
+            if (v->type != NXT_CONF_JSON_SHORT_STRING
+                && v->type != NXT_CONF_JSON_STRING)
+            {
+                return NXT_ERROR;
+            }
+
+            nxt_conf_json_value_get_string(v, &ptr->str);
+
+            break;
+
+
+        case NXT_CONF_JSON_MAP_PTR:
+
+            ptr->v = v;
+
+            break;
+        }
+    }
+
+    return NXT_OK;
+}
+
+
 nxt_int_t
 nxt_conf_json_op_compile(nxt_mp_t *mp, nxt_conf_json_op_t **ops,
     nxt_conf_json_value_t *root, nxt_str_t *path,