Update the documentation of JSON_DECODE_ANY

[jansson.git] / doc / apiref.rst

diff --git a/doc/apiref.rst b/doc/apiref.rst
index b49861d..d6b89e3 100644 (file)
--- a/doc/apiref.rst
+++ b/doc/apiref.rst
@@ -703,9 +703,9 @@ can be ORed together to obtain *flags*.
 ``JSON_INDENT(n)``
    Pretty-print the result, using newlines between array and object
    items, and indenting with *n* spaces. The valid range for *n* is
-   between 0 and 32, other values result in an undefined output. If
-   ``JSON_INDENT`` is not used or *n* is 0, no newlines are inserted
-   between array and object items.
+   between 0 and 31 (inclusive), other values result in an undefined
+   output. If ``JSON_INDENT`` is not used or *n* is 0, no newlines are
+   inserted between array and object items.
 
 ``JSON_COMPACT``
    This flag enables a compact representation, i.e. sets the separator
@@ -737,8 +737,7 @@ can be ORed together to obtain *flags*.
    **Note:** Encoding any value may be useful in some scenarios, but
    it's generally discouraged as it violates strict compatiblity with
    :rfc:`4627`. If you use this flag, don't expect interoperatibility
-   with other JSON systems. Even Jansson itself doesn't have any means
-   to decode JSON texts whose root value is not object or array.
+   with other JSON systems.
 
    .. versionadded:: 2.1
 
@@ -800,7 +799,8 @@ text to the Jansson representation of JSON data. The JSON
 specification requires that a JSON text is either a serialized array
 or object, and this requirement is also enforced with the following
 functions. In other words, the top level value in the JSON text being
-decoded must be either array or object.
+decoded must be either array or object. To decode any JSON value, use
+the ``JSON_DECODE_ANY`` flag (see below).
 
 See :ref:`rfc-conformance` for a discussion on Jansson's conformance
 to the JSON specification. It explains many design decisions that
@@ -828,6 +828,17 @@ macros can be ORed together to obtain *flags*.
 
    .. versionadded:: 2.1
 
+``JSON_DECODE_ANY``
+   By default, the decoder expects an array or object as the input.
+   With this flag enabled, the decoder accepts any valid JSON value.
+
+   **Note:** Decoding any value may be useful in some scenarios, but
+   it's generally discouraged as it violates strict compatiblity with
+   :rfc:`4627`. If you use this flag, don't expect interoperatibility
+   with other JSON systems.
+
+   .. versionadded:: 2.3
+
 The following functions perform the actual JSON decoding.
 
 .. function:: json_t *json_loads(const char *input, size_t flags, json_error_t *error)
@@ -859,6 +870,24 @@ The following functions perform the actual JSON decoding.
    filled with information about the error. *flags* is described
    above.
 
+   This function will start reading the input from whatever position
+   the input file was, without attempting to seek first. If an error
+   occurs, the file position will be left indeterminate. On success,
+   the file position will be at EOF, unless ``JSON_DISABLE_EOF_CHECK``
+   flag was used. In this case, the file position will be at the first
+   character after the last ``]`` or ``}`` in the JSON input. This
+   allows calling :func:`json_loadf()` on the same ``FILE`` object
+   multiple times, if the input consists of consecutive JSON texts,
+   possibly separated by whitespace.
+
+   If both ``JSON_DISABLE_EOF_CHECK`` and ``JSON_DECODE_ANY`` flags
+   are used, the decoder may read one extra UTF-8 code unit (up to 4
+   bytes of input). For example, decoding ``4true`` correctly decodes
+   the integer 4, but leaves the file position pointing at ``r``
+   instead of ``t``. For this reason, if reading multiple consecutive
+   values that are not arrays and objects, they should be separated by
+   at least one whitespace character.
+
 .. function:: json_t *json_load_file(const char *path, size_t flags, json_error_t *error)
 
    .. refcounting:: new
@@ -1191,6 +1220,8 @@ copied in a recursive fashion.
    Returns a deep copy of *value*, or *NULL* on error.
 
 
+.. _apiref-custom-memory-allocation:
+
 Custom Memory Allocation
 ========================
 
@@ -1259,5 +1290,5 @@ JSON structures by zeroing all memory when freed::
 For more information about the issues of storing sensitive data in
 memory, see
 http://www.dwheeler.com/secure-programs/Secure-Programs-HOWTO/protect-secrets.html.
-The page also examplains the :func:`guaranteed_memset()` function used
+The page also explains the :func:`guaranteed_memset()` function used
 in the example and gives a sample implementation for it.