Adding upstream version 2.4.38.upstream/2.4.38upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1037 insertions, 0 deletions

diff --git a/modules/md/md_json.c b/modules/md/md_json.c
new file mode 100644
index 0000000..f73ab14
--- /dev/null
+++ b/modules/md/md_json.c
@@ -0,0 +1,1037 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+ 
+#include <assert.h>
+#include <apr_lib.h>
+#include <apr_strings.h>
+#include <apr_buckets.h>
+
+#include "md_json.h"
+#include "md_log.h"
+#include "md_http.h"
+#include "md_util.h"
+
+/* jansson thinks everyone compiles with the platform's cc in its fullest capabilities
+ * when undefining their INLINEs, we get static, unused functions, arg 
+ */
+#if defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic push
+#endif
+#pragma GCC diagnostic ignored "-Wunused-function"
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
+
+#include <jansson_config.h>
+#undef  JSON_INLINE
+#define JSON_INLINE 
+#include <jansson.h>
+
+#if defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic pop
+#endif
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
+struct md_json_t {
+    apr_pool_t *p;
+    json_t *j;
+};
+
+/**************************************************************************************************/
+/* lifecycle */
+
+static apr_status_t json_pool_cleanup(void *data)
+{
+    md_json_t *json = data;
+    if (json) {
+        md_json_destroy(json);
+    }
+    return APR_SUCCESS;
+}
+
+static md_json_t *json_create(apr_pool_t *pool, json_t *j)
+{
+    md_json_t *json;
+    
+    if (!j) {
+        apr_abortfunc_t abfn = apr_pool_abort_get(pool);
+        if (abfn) {
+            abfn(APR_ENOMEM);
+        }
+        assert(j != NULL); /* failsafe in case abort is unset */
+    }
+    json = apr_pcalloc(pool, sizeof(*json));
+    json->p = pool;
+    json->j = j;
+    apr_pool_cleanup_register(pool, json, json_pool_cleanup, apr_pool_cleanup_null);
+        
+    return json;
+}
+
+md_json_t *md_json_create(apr_pool_t *pool)
+{
+    return json_create(pool, json_object());
+}
+
+md_json_t *md_json_create_s(apr_pool_t *pool, const char *s)
+{
+    return json_create(pool, json_string(s));
+}
+
+void md_json_destroy(md_json_t *json)
+{
+    if (json && json->j) {
+        assert(json->j->refcount > 0);
+        json_decref(json->j);
+        json->j = NULL;
+    }
+}
+
+md_json_t *md_json_copy(apr_pool_t *pool, md_json_t *json)
+{
+    return json_create(pool, json_copy(json->j));
+}
+
+md_json_t *md_json_clone(apr_pool_t *pool, md_json_t *json)
+{
+    return json_create(pool, json_deep_copy(json->j));
+}
+
+/**************************************************************************************************/
+/* selectors */
+
+
+static json_t *jselect(md_json_t *json, va_list ap)
+{
+    json_t *j;
+    const char *key;
+    
+    j = json->j;
+    key = va_arg(ap, char *);
+    while (key && j) {
+        j = json_object_get(j, key);
+        key = va_arg(ap, char *);
+    }
+    return j;
+}
+
+static json_t *jselect_parent(const char **child_key, int create, md_json_t *json, va_list ap)
+{
+    const char *key, *next;
+    json_t *j, *jn;
+    
+    *child_key = NULL;
+    j = json->j;
+    key = va_arg(ap, char *);
+    while (key && j) {
+        next = va_arg(ap, char *);
+        if (next) {
+            jn = json_object_get(j, key);
+            if (!jn && create) {
+                jn = json_object();
+                json_object_set_new(j, key, jn);
+            }
+            j = jn;
+        }
+        else {
+            *child_key = key;
+        }
+        key = next;
+    }
+    return j;
+}
+
+static apr_status_t jselect_add(json_t *val, md_json_t *json, va_list ap)
+{
+    const char *key;
+    json_t *j, *aj;
+    
+    j = jselect_parent(&key, 1, json, ap);
+    
+    if (!j || !json_is_object(j)) {
+        json_decref(val);
+        return APR_EINVAL;
+    }
+    
+    aj = json_object_get(j, key);
+    if (!aj) {
+        aj = json_array();
+        json_object_set_new(j, key, aj);
+    }
+    
+    if (!json_is_array(aj)) {
+        json_decref(val);
+        return APR_EINVAL;
+    }
+
+    json_array_append(aj, val);
+    return APR_SUCCESS;
+}
+
+static apr_status_t jselect_set(json_t *val, md_json_t *json, va_list ap)
+{
+    const char *key;
+    json_t *j;
+    
+    j = jselect_parent(&key, 1, json, ap);
+    
+    if (!j) {
+        json_decref(val);
+        return APR_EINVAL;
+    }
+    
+    if (key) {
+        if (!json_is_object(j)) {
+            json_decref(val);
+            return APR_EINVAL;
+        }
+        json_object_set(j, key, val);
+    }
+    else {
+        /* replace */
+        if (json->j) {
+            json_decref(json->j);
+        }
+        json_incref(val);
+        json->j = val;
+    }
+    return APR_SUCCESS;
+}
+
+static apr_status_t jselect_set_new(json_t *val, md_json_t *json, va_list ap)
+{
+    const char *key;
+    json_t *j;
+    
+    j = jselect_parent(&key, 1, json, ap);
+    
+    if (!j) {
+        json_decref(val);
+        return APR_EINVAL;
+    }
+    
+    if (key) {
+        if (!json_is_object(j)) {
+            json_decref(val);
+            return APR_EINVAL;
+        }
+        json_object_set_new(j, key, val);
+    }
+    else {
+        /* replace */
+        if (json->j) {
+            json_decref(json->j);
+        }
+        json->j = val;
+    }
+    return APR_SUCCESS;
+}
+
+int md_json_has_key(md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+
+    return j != NULL;
+}
+
+/**************************************************************************************************/
+/* booleans */
+
+int md_json_getb(md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+
+    return j? json_is_true(j) : 0;
+}
+
+apr_status_t md_json_setb(int value, md_json_t *json, ...)
+{
+    va_list ap;
+    apr_status_t rv;
+    
+    va_start(ap, json);
+    rv = jselect_set_new(json_boolean(value), json, ap);
+    va_end(ap);
+    return rv;
+}
+
+/**************************************************************************************************/
+/* numbers */
+
+double md_json_getn(md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+    return (j && json_is_number(j))? json_number_value(j) : 0.0;
+}
+
+apr_status_t md_json_setn(double value, md_json_t *json, ...)
+{
+    va_list ap;
+    apr_status_t rv;
+    
+    va_start(ap, json);
+    rv = jselect_set_new(json_real(value), json, ap);
+    va_end(ap);
+    return rv;
+}
+
+/**************************************************************************************************/
+/* longs */
+
+long md_json_getl(md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+    return (long)((j && json_is_number(j))? json_integer_value(j) : 0L);
+}
+
+apr_status_t md_json_setl(long value, md_json_t *json, ...)
+{
+    va_list ap;
+    apr_status_t rv;
+    
+    va_start(ap, json);
+    rv = jselect_set_new(json_integer(value), json, ap);
+    va_end(ap);
+    return rv;
+}
+
+/**************************************************************************************************/
+/* strings */
+
+const char *md_json_gets(md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+
+    return (j && json_is_string(j))? json_string_value(j) : NULL;
+}
+
+const char *md_json_dups(apr_pool_t *p, md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+
+    return (j && json_is_string(j))? apr_pstrdup(p, json_string_value(j)) : NULL;
+}
+
+apr_status_t md_json_sets(const char *value, md_json_t *json, ...)
+{
+    va_list ap;
+    apr_status_t rv;
+    
+    va_start(ap, json);
+    rv = jselect_set_new(json_string(value), json, ap);
+    va_end(ap);
+    return rv;
+}
+
+/**************************************************************************************************/
+/* json itself */
+
+md_json_t *md_json_getj(md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+    
+    if (j) {
+        if (j == json->j) {
+            return json;
+        }
+        json_incref(j);
+        return json_create(json->p, j);
+    }
+    return NULL;
+}
+
+apr_status_t md_json_setj(md_json_t *value, md_json_t *json, ...)
+{
+    va_list ap;
+    apr_status_t rv;
+    const char *key;
+    json_t *j;
+    
+    if (value) {
+        va_start(ap, json);
+        rv = jselect_set(value->j, json, ap);
+        va_end(ap);
+    }
+    else {
+        va_start(ap, json);
+        j = jselect_parent(&key, 1, json, ap);
+        va_end(ap);
+        
+        if (key && j && !json_is_object(j)) {
+            json_object_del(j, key);
+            rv = APR_SUCCESS;
+        }
+        else {
+            rv = APR_EINVAL;
+        }
+    }
+    return rv;
+}
+
+apr_status_t md_json_addj(md_json_t *value, md_json_t *json, ...)
+{
+    va_list ap;
+    apr_status_t rv;
+    
+    va_start(ap, json);
+    rv = jselect_add(value->j, json, ap);
+    va_end(ap);
+    return rv;
+}
+
+
+/**************************************************************************************************/
+/* arrays / objects */
+
+apr_status_t md_json_clr(md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+
+    if (j && json_is_object(j)) {
+        json_object_clear(j);
+    }
+    else if (j && json_is_array(j)) {
+        json_array_clear(j);
+    }
+    return APR_SUCCESS;
+}
+
+apr_status_t md_json_del(md_json_t *json, ...)
+{
+    const char *key;
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect_parent(&key, 0, json, ap);
+    va_end(ap);
+    
+    if (key && j && json_is_object(j)) {
+        json_object_del(j, key);
+    }
+    return APR_SUCCESS;
+}
+
+/**************************************************************************************************/
+/* object strings */
+
+apr_status_t md_json_gets_dict(apr_table_t *dict, md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+
+    if (j && json_is_object(j)) {
+        const char *key;
+        json_t *val;
+        
+        json_object_foreach(j, key, val) {
+            if (json_is_string(val)) {
+                apr_table_set(dict, key, json_string_value(val));
+            }
+        }
+        return APR_SUCCESS;
+    }
+    return APR_ENOENT;
+}
+
+static int object_set(void *data, const char *key, const char *val)
+{
+    json_t *j = data, *nj = json_string(val);
+    json_object_set(j, key, nj);
+    json_decref(nj);
+    return 1;
+}
+ 
+apr_status_t md_json_sets_dict(apr_table_t *dict, md_json_t *json, ...)
+{
+    json_t *nj, *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+    
+    if (!j || !json_is_object(j)) {
+        const char *key;
+        
+        va_start(ap, json);
+        j = jselect_parent(&key, 1, json, ap);
+        va_end(ap);
+        
+        if (!key || !j || !json_is_object(j)) {
+            return APR_EINVAL;
+        }
+        nj = json_object();
+        json_object_set_new(j, key, nj);
+        j = nj; 
+    }
+    
+    apr_table_do(object_set, j, dict, NULL);
+    return APR_SUCCESS;
+}
+
+/**************************************************************************************************/
+/* conversions */
+
+apr_status_t md_json_pass_to(void *value, md_json_t *json, apr_pool_t *p, void *baton)
+{
+    (void)p;
+    (void)baton;
+    return md_json_setj(value, json, NULL);
+}
+
+apr_status_t md_json_pass_from(void **pvalue, md_json_t *json, apr_pool_t *p, void *baton)
+{
+    (void)p;
+    (void)baton;
+    *pvalue = json;
+    return APR_SUCCESS;
+}
+
+apr_status_t md_json_clone_to(void *value, md_json_t *json, apr_pool_t *p, void *baton)
+{
+    (void)baton;
+    return md_json_setj(md_json_clone(p, value), json, NULL);
+}
+
+apr_status_t md_json_clone_from(void **pvalue, md_json_t *json, apr_pool_t *p, void *baton)
+{
+    (void)baton;
+    *pvalue = md_json_clone(p, json);
+    return APR_SUCCESS;
+}
+
+/**************************************************************************************************/
+/* array generic */
+
+apr_status_t md_json_geta(apr_array_header_t *a, md_json_from_cb *cb, void *baton,
+                          md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    apr_status_t rv = APR_SUCCESS;
+    size_t index;
+    json_t *val;
+    md_json_t wrap;
+    void *element;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+    
+    if (!j || !json_is_array(j)) {
+        return APR_ENOENT;
+    }
+        
+    wrap.p = a->pool;
+    json_array_foreach(j, index, val) {
+        wrap.j = val;
+        if (APR_SUCCESS == (rv = cb(&element, &wrap, wrap.p, baton))) {
+            if (element) {
+                APR_ARRAY_PUSH(a, void*) = element;
+            }
+        }
+        else if (APR_ENOENT == rv) {
+            rv = APR_SUCCESS;
+        }
+        else {
+            break;
+        }
+    }
+    return rv;
+}
+
+apr_status_t md_json_seta(apr_array_header_t *a, md_json_to_cb *cb, void *baton, 
+                          md_json_t *json, ...)
+{
+    json_t *j, *nj;
+    md_json_t wrap;
+    apr_status_t rv = APR_SUCCESS;
+    va_list ap;
+    int i;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+    
+    if (!j || !json_is_array(j)) {
+        const char *key;
+        
+        va_start(ap, json);
+        j = jselect_parent(&key, 1, json, ap);
+        va_end(ap);
+        
+        if (!key || !j || !json_is_object(j)) {
+            return APR_EINVAL;
+        }
+        nj = json_array();
+        json_object_set_new(j, key, nj);
+        j = nj; 
+    }
+    
+    json_array_clear(j);
+    wrap.p = json->p;
+    for (i = 0; i < a->nelts; ++i) {
+        if (!cb) {
+            return APR_EINVAL;
+        }    
+        wrap.j = json_string("");
+        if (APR_SUCCESS == (rv = cb(APR_ARRAY_IDX(a, i, void*), &wrap, json->p, baton))) {
+            json_array_append_new(j, wrap.j);
+        }
+    }
+    return rv;
+}
+
+int md_json_itera(md_json_itera_cb *cb, void *baton, md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    size_t index;
+    json_t *val;
+    md_json_t wrap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+    
+    if (!j || !json_is_array(j)) {
+        return 0;
+    }
+        
+    wrap.p = json->p;
+    json_array_foreach(j, index, val) {
+        wrap.j = val;
+        if (!cb(baton, index, &wrap)) {
+            return 0;
+        }
+    }
+    return 1;
+}
+
+/**************************************************************************************************/
+/* array strings */
+
+apr_status_t md_json_getsa(apr_array_header_t *a, md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+
+    if (j && json_is_array(j)) {
+        size_t index;
+        json_t *val;
+        
+        json_array_foreach(j, index, val) {
+            if (json_is_string(val)) {
+                APR_ARRAY_PUSH(a, const char *) = json_string_value(val);
+            }
+        }
+        return APR_SUCCESS;
+    }
+    return APR_ENOENT;
+}
+
+apr_status_t md_json_dupsa(apr_array_header_t *a, apr_pool_t *p, md_json_t *json, ...)
+{
+    json_t *j;
+    va_list ap;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+
+    if (j && json_is_array(j)) {
+        size_t index;
+        json_t *val;
+        
+        json_array_foreach(j, index, val) {
+            if (json_is_string(val)) {
+                APR_ARRAY_PUSH(a, const char *) = apr_pstrdup(p, json_string_value(val));
+            }
+        }
+        return APR_SUCCESS;
+    }
+    return APR_ENOENT;
+}
+
+apr_status_t md_json_setsa(apr_array_header_t *a, md_json_t *json, ...)
+{
+    json_t *nj, *j;
+    va_list ap;
+    int i;
+    
+    va_start(ap, json);
+    j = jselect(json, ap);
+    va_end(ap);
+    
+    if (!j || !json_is_array(j)) {
+        const char *key;
+        
+        va_start(ap, json);
+        j = jselect_parent(&key, 1, json, ap);
+        va_end(ap);
+        
+        if (!key || !j || !json_is_object(j)) {
+            return APR_EINVAL;
+        }
+        nj = json_array();
+        json_object_set_new(j, key, nj);
+        j = nj; 
+    }
+    
+    json_array_clear(j);
+    for (i = 0; i < a->nelts; ++i) {
+        json_array_append_new(j, json_string(APR_ARRAY_IDX(a, i, const char*)));
+    }
+    return APR_SUCCESS;
+}
+
+/**************************************************************************************************/
+/* formatting, parsing */
+
+typedef struct {
+    md_json_t *json;
+    md_json_fmt_t fmt;
+    const char *fname;
+    apr_file_t *f;
+} j_write_ctx;
+
+/* Convert from md_json_fmt_t to the Jansson json_dumpX flags. */
+static size_t fmt_to_flags(md_json_fmt_t fmt)
+{
+    /* NOTE: JSON_PRESERVE_ORDER is off by default before Jansson 2.8. It
+     * doesn't have any semantic effect on the protocol, but it does let the
+     * md_json_writeX unit tests run deterministically. */
+    return JSON_PRESERVE_ORDER |
+           ((fmt == MD_JSON_FMT_COMPACT) ? JSON_COMPACT : JSON_INDENT(2)); 
+}
+
+static int dump_cb(const char *buffer, size_t len, void *baton)
+{
+    apr_bucket_brigade *bb = baton;
+    apr_status_t rv;
+    
+    rv = apr_brigade_write(bb, NULL, NULL, buffer, len);
+    return (rv == APR_SUCCESS)? 0 : -1;
+}
+
+apr_status_t md_json_writeb(md_json_t *json, md_json_fmt_t fmt, apr_bucket_brigade *bb)
+{
+    int rv = json_dump_callback(json->j, dump_cb, bb, fmt_to_flags(fmt));
+    return rv? APR_EGENERAL : APR_SUCCESS;
+}
+
+static int chunk_cb(const char *buffer, size_t len, void *baton)
+{
+    apr_array_header_t *chunks = baton;
+    char *chunk = apr_pcalloc(chunks->pool, len+1);
+    
+    memcpy(chunk, buffer, len);
+    APR_ARRAY_PUSH(chunks, const char *) = chunk;
+    return 0;
+}
+
+const char *md_json_writep(md_json_t *json, apr_pool_t *p, md_json_fmt_t fmt)
+{
+    apr_array_header_t *chunks;
+    int rv;
+
+    chunks = apr_array_make(p, 10, sizeof(char *));
+    rv = json_dump_callback(json->j, chunk_cb, chunks, fmt_to_flags(fmt));
+
+    if (rv) {
+        md_log_perror(MD_LOG_MARK, MD_LOG_ERR, 0, p,
+                      "md_json_writep failed to dump JSON");
+        return NULL;
+    }
+
+    switch (chunks->nelts) {
+        case 0:
+            return "";
+        case 1:
+            return APR_ARRAY_IDX(chunks, 0, const char *);
+        default:
+            return apr_array_pstrcat(p, chunks, 0);
+    }
+}
+
+apr_status_t md_json_writef(md_json_t *json, apr_pool_t *p, md_json_fmt_t fmt, apr_file_t *f)
+{
+    apr_status_t rv;
+    const char *s;
+    
+    s = md_json_writep(json, p, fmt);
+
+    if (s) {
+        rv = apr_file_write_full(f, s, strlen(s), NULL);
+    }
+    else {
+        rv = APR_EINVAL;
+    }
+
+    if (APR_SUCCESS != rv) {
+        md_log_perror(MD_LOG_MARK, MD_LOG_ERR, rv, json->p, "md_json_writef");
+    }
+    return rv;
+}
+
+apr_status_t md_json_fcreatex(md_json_t *json, apr_pool_t *p, md_json_fmt_t fmt, 
+                              const char *fpath, apr_fileperms_t perms)
+{
+    apr_status_t rv;
+    apr_file_t *f;
+    
+    rv = md_util_fcreatex(&f, fpath, perms, p);
+    if (APR_SUCCESS == rv) {
+        rv = md_json_writef(json, p, fmt, f);
+        apr_file_close(f);
+    }
+    return rv;
+}
+
+static apr_status_t write_json(void *baton, apr_file_t *f, apr_pool_t *p)
+{
+    j_write_ctx *ctx = baton;
+    apr_status_t rv = md_json_writef(ctx->json, p, ctx->fmt, f);
+    if (APR_SUCCESS != rv) {
+        md_log_perror(MD_LOG_MARK, MD_LOG_ERR, rv, p, "freplace json in %s", ctx->fname);
+    }
+    return rv;
+}
+
+apr_status_t md_json_freplace(md_json_t *json, apr_pool_t *p, md_json_fmt_t fmt, 
+                              const char *fpath, apr_fileperms_t perms)
+{
+    j_write_ctx ctx;
+    ctx.json = json;
+    ctx.fmt = fmt;
+    ctx.fname = fpath;
+    return md_util_freplace(fpath, perms, p, write_json, &ctx);
+}
+
+apr_status_t md_json_readd(md_json_t **pjson, apr_pool_t *pool, const char *data, size_t data_len)
+{
+    json_error_t error;
+    json_t *j;
+    
+    j = json_loadb(data, data_len, 0, &error);
+    if (!j) {
+        return APR_EINVAL;
+    }
+    *pjson = json_create(pool, j);
+    return APR_SUCCESS;
+}
+
+static size_t load_cb(void *data, size_t max_len, void *baton)
+{
+    apr_bucket_brigade *body = baton;
+    size_t blen, read_len = 0;
+    const char *bdata;
+    char *dest = data;
+    apr_bucket *b;
+    apr_status_t rv;
+    
+    while (body && !APR_BRIGADE_EMPTY(body) && max_len > 0) {
+        b = APR_BRIGADE_FIRST(body);
+        if (APR_BUCKET_IS_METADATA(b)) {
+            if (APR_BUCKET_IS_EOS(b)) {
+                body = NULL;
+            }
+        }
+        else {
+            rv = apr_bucket_read(b, &bdata, &blen, APR_BLOCK_READ);
+            if (rv == APR_SUCCESS) {
+                if (blen > max_len) {
+                    apr_bucket_split(b, max_len);
+                    blen = max_len;
+                }
+                memcpy(dest, bdata, blen);
+                read_len += blen;
+                max_len -= blen;
+                dest += blen;
+            }
+            else {
+                body = NULL;
+                if (!APR_STATUS_IS_EOF(rv)) {
+                    /* everything beside EOF is an error */
+                    read_len = (size_t)-1;
+                }
+            }
+        }
+        APR_BUCKET_REMOVE(b);
+        apr_bucket_delete(b);
+    }
+    
+    return read_len;
+}
+
+apr_status_t md_json_readb(md_json_t **pjson, apr_pool_t *pool, apr_bucket_brigade *bb)
+{
+    json_error_t error;
+    json_t *j;
+    
+    j = json_load_callback(load_cb, bb, 0, &error);
+    if (!j) {
+        return APR_EINVAL;
+    }
+    *pjson = json_create(pool, j);
+    return APR_SUCCESS;
+}
+
+static size_t load_file_cb(void *data, size_t max_len, void *baton)
+{
+    apr_file_t *f = baton;
+    apr_size_t len = max_len;
+    apr_status_t rv;
+    
+    rv = apr_file_read(f, data, &len);
+    if (APR_SUCCESS == rv) {
+        return len;
+    }
+    else if (APR_EOF == rv) {
+        return 0;
+    }
+    return (size_t)-1;
+}
+
+apr_status_t md_json_readf(md_json_t **pjson, apr_pool_t *p, const char *fpath)
+{
+    apr_file_t *f;
+    json_t *j;
+    apr_status_t rv;
+    json_error_t error;
+    
+    rv = apr_file_open(&f, fpath, APR_FOPEN_READ, 0, p);
+    if (rv != APR_SUCCESS) {
+        return rv;
+    }
+
+    j = json_load_callback(load_file_cb, f, 0, &error);
+    if (j) {
+        *pjson = json_create(p, j);
+    }
+    else {
+        md_log_perror(MD_LOG_MARK, MD_LOG_ERR, 0, p,
+                      "failed to load JSON file %s: %s (line %d:%d)",
+                      fpath, error.text, error.line, error.column);
+    }
+
+    apr_file_close(f);
+    return (j && *pjson) ? APR_SUCCESS : APR_EINVAL;
+}
+
+/**************************************************************************************************/
+/* http get */
+
+apr_status_t md_json_read_http(md_json_t **pjson, apr_pool_t *pool, const md_http_response_t *res)
+{
+    apr_status_t rv = APR_ENOENT;
+    if (res->rv == APR_SUCCESS) {
+        const char *ctype = apr_table_get(res->headers, "content-type");
+        if (ctype && res->body && (strstr(ctype, "/json") || strstr(ctype, "+json"))) {
+            rv = md_json_readb(pjson, pool, res->body);
+        }
+    }
+    return rv;
+}
+
+typedef struct {
+    apr_status_t rv;
+    apr_pool_t *pool;
+    md_json_t *json;
+} resp_data;
+
+static apr_status_t json_resp_cb(const md_http_response_t *res)
+{
+    resp_data *resp = res->req->baton;
+    return md_json_read_http(&resp->json, resp->pool, res);
+}
+
+apr_status_t md_json_http_get(md_json_t **pjson, apr_pool_t *pool,
+                              struct md_http_t *http, const char *url)
+{
+    long req_id;
+    apr_status_t rv;
+    resp_data resp;
+    
+    memset(&resp, 0, sizeof(resp));
+    resp.pool = pool;
+    
+    rv = md_http_GET(http, url, NULL, json_resp_cb, &resp, &req_id);
+    
+    if (rv == APR_SUCCESS) {
+        md_http_await(http, req_id);
+        *pjson = resp.json;
+        return resp.rv;
+    }
+    *pjson = NULL;
+    return rv;
+}
+