nerdcruft/libcruft-util
1
0
Fork 0
Code Issues Releases Activity

json: support sax- and dom-like interfaces

Browse Source
This commit is contained in:
Danny Robson 2015-02-02 23:00:38 +11:00
parent cfc0f8ecd0
commit 0e1eaa91d3
5 changed files with 345 additions and 221 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

474
json.cpp.rl
View File

@ -14,7 +14,7 @@
* You should have received a copy of the GNU General Public License
* along with libgim. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2010-2012 Danny Robson <danny@nerdcruft.net>
* Copyright 2010-2015 Danny Robson <danny@nerdcruft.net>
*/
@ -41,215 +41,172 @@ using namespace std;
using namespace util;
//-----------------------------------------------------------------------------
// Parsing
struct parse_context {
parse_context(json::tree::node *_root):
root (_root),
value (NULL),
key (NULL),
start (NULL),
stop (NULL)
{ ; }
json::tree::node *root,
*value,
*key;
const char *start,
*stop;
};
%%{
# JSON (rfc7159)
machine json;
## Record whether parsing was successful for future use
action success
{ __success = true; }
action trace { if (false) std::cerr << *p; }
action success { __success = true; }
action failure { }
action failure {
__success = false;
/*std::cerr << std::endl
<< "Failure on: '" << fc << "' in level " << top << " at " << fpc - p
<< std::endl;
*/
}
action new_line { ++line; }
action first { parsed.push_back ({ type::UNKNOWN, p, p}); }
action last { parsed.back ().last = p; }
action tag_nul { parsed.back ().tag = type::NUL; }
action tag_boolean { parsed.back ().tag = type::BOOLEAN; }
action tag_string { parsed.back ().tag = type::STRING; }
action tag_integer { parsed.back ().tag = type::INTEGER; }
action tag_real { parsed.back ().tag = type::REAL; }
action tag_object_begin { parsed.push_back ({ type::OBJECT_BEGIN, p, p + 1 }); }
action tag_object_end { parsed.push_back ({ type::OBJECT_END, p, p + 1 }); }
action tag_array_begin { parsed.push_back ({ type::ARRAY_BEGIN, p, p + 1 }); }
action tag_array_end { parsed.push_back ({ type::ARRAY_END, p, p + 1 }); }
# Line counter
lines = (
any | '\n' @new_line
)*;
# UTF-8 (rfc3629)
utf8_tail = 0x80..0xbf;
utf8_1 = 0x00..0x7f;
utf8_2 = 0xc2..0xdf utf8_tail;
utf8_3 = 0xe0 0xa0..0xbf utf8_tail |
0xe1..0xec utf8_tail{2} |
0xed 0x80..0x9f utf8_tail |
0xee..0xef utf8_tail{2};
utf8_4 = 0xf0 0x90..0xbf utf8_tail{2} |
0xf1..0xf3 utf8_tail{3} |
0xf4 0x80..0x8f utf8_tail{2};
action new_object { nodestack.push_back (parse_context(new json::tree::object)); }
action new_array { nodestack.push_back (parse_context(new json::tree::array)); }
utf8 = utf8_1 | utf8_2 | utf8_3 | utf8_4;
action new_object_value {
CHECK (nodestack.back ().root->is_object ());
CHECK (nodestack.back ().key);
CHECK (nodestack.back ().value);
# Utility
ws = 0x20 | 0x09 | 0x0A | 0x0D;
array_start = '[';
array_end = ']';
object_start = '{';
object_end = '}';
if (!nodestack.back ().key->is_string ())
throw parse_error ("object keys must be strings");
# Strings
char =
(utf8 - ["\\])
| "\\" (
[\\"/bfnrt]
| "u" xdigit{4}
)
;
json::tree::object *object = (json::tree::object*)nodestack.back ().root;
object->insert (nodestack.back ().key->as_string (),
unique_ptr<json::tree::node> (nodestack.back ().value));
nodestack.back ().key = NULL;
nodestack.back ().value = NULL;
}
string = ('"' char* '"') >first >tag_string %*last;
action new_array_value {
CHECK (nodestack.back ().root->is_array ());
CHECK (nodestack.back ().value);
# numbers
int = '0' | [1-9] digit*;
json::tree::array *array = (json::tree::array *)nodestack.back ().root;
array->insert (unique_ptr<json::tree::node> (nodestack.back ().value));
nodestack.back ().value = NULL;
}
frac = '.' digit+;
e = 'e'i[+\-]?;
exp = e digit+;
action new_string {
CHECK (!nodestack.empty ());
CHECK (!nodestack.back ().value);
number = (
'-'?
int
(frac >tag_real)?
exp?
) >tag_integer;
std::string value (std::string (nodestack.back ().start,
nodestack.back ().stop));
nodestack.back ().value = new json::tree::string(value);
}
# wrapper types
array = array_start @{ fhold; fcall array_members; } array_end;
object = object_start @{ fhold; fcall object_members; } object_end;
action new_boolean {
CHECK (!nodestack.empty ());
CHECK (!nodestack.back ().value);
# simple types; case sensitive literals
bool = ("true" | "false") >tag_boolean;
nul = "null" >tag_nul;
literal = bool | nul;
throw parse_error ("unable to parse boolean");
}
value = object | array | (number | string | literal) >first %last;
action new_number {
CHECK (!nodestack.empty ());
# Complex
member = string ws* ':' ws* value;
parse_context &back = nodestack.back ();
CHECK (!back.value);
CHECK (back.start);
CHECK (back.stop);
CHECK_LE (back.start, back.stop);
array_members := ((
array_start >tag_array_begin ws* (value ws* (',' ws* value ws*)*)? array_end >tag_array_end
) & lines)
@{ fhold; fret; } $trace $!failure;
errno = 0;
char *end;
double value = strtod (back.start, &end);
if (end == back.start || errno)
throw parse_error ("unable to parse number");
back.value = new json::tree::number (value);
}
object_members := ((
object_start >tag_object_begin ws* (member ws* (',' ws* member ws*)*)? object_end >tag_object_end
) & lines)
@{ fhold; fret; } $trace $!failure;
action new_null {
CHECK (!nodestack.empty ());
CHECK (!nodestack.back ().value);
# meta types
document := ((ws* value ws*) & lines)
%success
$!failure
$trace;
nodestack.back().value = new json::tree::null ();
}
action new_object_key {
CHECK (!nodestack.empty ());
CHECK (nodestack.back ().root->is_object ());
CHECK (nodestack.back ().value);
CHECK (!nodestack.back ().key);
nodestack.back ().key = nodestack.back ().value;
nodestack.back ().value = NULL;
}
prepush {
fsmstack.push_back (0);
}
postpop {
fsmstack.pop_back ();
__root = nodestack.back ().root;
if (nodestack.size () > 1)
(nodestack.rbegin () + 1)->value = nodestack.back ().root;
nodestack.pop_back ();
}
variable stack fsmstack;
alphtype char;
## numerical
exp = [eE]('-' | '+')? digit+;
frac = '.' digit+;
int = '-'? [1-9]? digit+;
number = int ( frac
| exp
| frac exp)?;
## textual
char =
any - (cntrl | '\"' | '\\')
| '\\\"'
| '\\\\'
| '\\/'
| '\\b'
| '\\f'
| '\\n'
| '\\r'
| '\\t'
| '\\u' xdigit{4};
string = ('"'
char* >{ nodestack.back ().start = fpc; }
%{ nodestack.back ().stop = fpc; })
'"'
@new_string;
## other
boolean =
'true' @{ nodestack.back ().value = new json::tree::boolean ( true); }
| 'false' @{ nodestack.back ().value = new json::tree::boolean (false); };
## components
object = '{' @{ fhold; fcall _object; } '}';
array = '[' @{ fhold; fcall _array; } ']';
value =
string
| boolean
| number >{ nodestack.back ().start = fpc; } %{ nodestack.back ().stop = fpc; } %new_number
| object
| array
| 'null' %new_null;
## compound data types
_array := ('[' @new_array
space* ((value %new_array_value space* ',' space*)* value %new_array_value space*)?
']')
$!failure
@{ fhold; fret; };
pair = string %new_object_key space* ':' space* value %new_object_value;
_object := ('{' @new_object
space* ((pair space* ',' space*)* pair space*)?
'}')
$!failure
@{ fhold; fret; };
json := (space* (object | array) space*)
$!failure
%success
>{ __success = false; };
variable stack ragelstack;
prepush { ragelstack.push_back (0); }
postpop { ragelstack.pop_back (); }
write data;
}%%
std::ostream& operator<< (std::ostream &os, json::flat::type);
//-----------------------------------------------------------------------------
std::vector<json::flat::item>
json::flat::parse (const char *first, const char *last)
{
const char *p = first;
const char *pe = last;
const char *eof = pe;
std::deque<int> ragelstack;
std::vector<item> parsed;
size_t line = 0;
int cs, top;
bool __success = false;
%%write init;
%%write exec;
if (!__success)
throw parse_error (line, "parse error");
return parsed;
}
std::vector<json::flat::item>
json::flat::parse (const boost::filesystem::path &path)
{
util::mapped_file f (path);
return parse ((const char *)f.cbegin (), (const char*)f.cend ());
}
//-----------------------------------------------------------------------------
// External support
template <>
bool
is_integer (const json::tree::number &node) {
is_integer (const json::tree::number &node)
{
return is_integer (node.native ());
}
template <>
bool
is_integer (const json::tree::node &node) {
is_integer (const json::tree::node &node)
{
return node.is_number () &&
is_integer (node.as_number ());
}
@ -257,11 +214,110 @@ is_integer (const json::tree::node &node) {
//-----------------------------------------------------------------------------
// Node
static std::vector<json::flat::item>::const_iterator
parse (std::vector<json::flat::item>::const_iterator first,
std::vector<json::flat::item>::const_iterator last,
std::unique_ptr<json::tree::node> &output);
//-----------------------------------------------------------------------------
static std::vector<json::flat::item>::const_iterator
parse (std::vector<json::flat::item>::const_iterator first,
std::vector<json::flat::item>::const_iterator last,
json::tree::array &parent)
{
for (auto cursor = first; cursor != last; ) {
if (cursor->tag == json::flat::type::ARRAY_END)
return cursor + 1;
std::unique_ptr<json::tree::node> value;
cursor = ::parse (cursor, last, value);
parent.insert (std::move (value));
}
unreachable ();
}
//-----------------------------------------------------------------------------
static std::vector<json::flat::item>::const_iterator
parse (std::vector<json::flat::item>::const_iterator first,
std::vector<json::flat::item>::const_iterator last,
json::tree::object &parent)
{
for (auto cursor = first; cursor != last; ) {
if (cursor->tag == json::flat::type::OBJECT_END)
return cursor + 1;
CHECK_EQ (cursor->tag, json::flat::type::STRING);
std::string key (cursor->first + 1, cursor->last - 1);
++cursor;
std::unique_ptr<json::tree::node> val;
cursor = ::parse (cursor, last, val);
parent.insert (key, std::move (val));
}
unreachable ();
}
//-----------------------------------------------------------------------------
static std::vector<json::flat::item>::const_iterator
parse (std::vector<json::flat::item>::const_iterator first,
std::vector<json::flat::item>::const_iterator last,
std::unique_ptr<json::tree::node> &output)
{
CHECK (first != last);
CHECK (output.get () == nullptr);
switch (first->tag) {
case json::flat::type::NUL:
output.reset (new json::tree::null ());
return first + 1;
case json::flat::type::BOOLEAN:
CHECK (*first->first == 't' || *first->first == 'f');
output.reset (new json::tree::boolean (*first->first == 't'));
return first + 1;
case json::flat::type::STRING:
CHECK_NEQ (first->first, first->last);
output.reset (new json::tree::string (first->first + 1, first->last - 1));
return first + 1;
case json::flat::type::INTEGER:
case json::flat::type::REAL:
output.reset (new json::tree::number (std::atof (first->first)));
return first + 1;
case json::flat::type::ARRAY_BEGIN: {
auto value = std::make_unique<json::tree::array> ();
auto cursor = ::parse (first + 1, last, *value);
output = std::move (value);
return cursor;
}
case json::flat::type::OBJECT_BEGIN: {
auto value = std::make_unique<json::tree::object> ();
auto cursor = ::parse (first + 1, last, *value);
output = std::move (value);
return cursor;
}
default:
unreachable ();
}
}
//-----------------------------------------------------------------------------
std::unique_ptr<json::tree::node>
json::tree::parse (const boost::filesystem::path &path) {
auto data = slurp (path);
return parse (static_cast <const char *> (data.get ()));
json::tree::parse (const boost::filesystem::path &path)
{
util::mapped_file f (path);
return parse ((const char*)f.cbegin (), (const char*)f.cend ());
}
@ -269,32 +325,6 @@ std::unique_ptr<json::tree::node>
json::tree::parse (const std::string &path)
{ return parse (path.c_str (), path.c_str () + path.size ()); }
std::unique_ptr<json::tree::node>
json::tree::parse (const char *start,
const char *stop) {
bool __success = true;
json::tree::node *__root = nullptr;
size_t top = 0;
int cs;
deque <int> fsmstack;
deque <parse_context> nodestack;
const char *p = start,
*pe = stop,
*eof = stop;
%%write init;
%%write exec;
if (!__success) {
std::ostringstream os;
os << "unable to parse json at char " << (p - start);
throw parse_error (os.str ());
}
return std::unique_ptr<json::tree::node> (__root);
}
std::unique_ptr<json::tree::node>
json::tree::parse (const char *start)
@ -306,6 +336,20 @@ json::tree::write (const json::tree::node &node, std::ostream &os)
{ node.write (os); }
std::unique_ptr<json::tree::node>
json::tree::parse (const char *first, const char *last)
{
std::unique_ptr<json::tree::node> output;
auto data = json::flat::parse (first, last);
auto end = ::parse (data.cbegin (), data.cend (), output);
CHECK (end == data.cend ());
(void)end;
return output;
}
//-----------------------------------------------------------------------------
// Type conversion
@ -605,3 +649,27 @@ namespace json { namespace tree {
return std::unique_ptr<node> (new number (f));
}
} }
//-----------------------------------------------------------------------------
std::ostream&
operator<< (std::ostream &os, json::flat::type t)
{
switch (t) {
case json::flat::type::STRING: os << "STRING"; break;
case json::flat::type::NUL: os << "NUL"; break;
case json::flat::type::BOOLEAN: os << "BOOLEAN"; break;
case json::flat::type::INTEGER: os << "INTEGER"; break;
case json::flat::type::REAL: os << "REAL"; break;
case json::flat::type::OBJECT_BEGIN: os << "OBJECT_BEGIN"; break;
case json::flat::type::OBJECT_END: os << "OBJECT_END"; break;
case json::flat::type::ARRAY_BEGIN: os << "ARRAY_BEGIN"; break;
case json::flat::type::ARRAY_END: os << "ARRAY_END"; break;
default:
unreachable ();
}
return os;
}

58
json.hpp
View File

@ -14,7 +14,7 @@
* You should have received a copy of the GNU General Public License
* along with libgim. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2010-2012 Danny Robson <danny@nerdcruft.net>
* Copyright 2010-2015 Danny Robson <danny@nerdcruft.net>
*/
#ifndef __UTIL_JSON_HPP
@ -287,6 +287,62 @@ namespace json {
static T deserialise (const json::tree::node&);
};
}
namespace flat {
enum class type {
UNKNOWN,
NUL,
BOOLEAN,
STRING,
INTEGER,
REAL,
OBJECT_BEGIN,
OBJECT_END,
ARRAY_BEGIN,
ARRAY_END
};
struct item {
type tag;
const char *first;
const char *last;
template <typename T>
T as (void) const;
};
std::vector<item> parse (const char *first, const char *last);
std::vector<item> parse (const char *first);
std::vector<item> parse (const boost::filesystem::path&);
//-----------------------------------------------------------------------------
struct error : public std::runtime_error {
error (const std::string &&_what):
runtime_error (std::move (_what))
{ ; }
};
struct parse_error : public error {
parse_error (size_t _line, const std::string &&_what):
error (std::move (_what)),
line (_line)
{ ; }
size_t line;
};
struct value_error : public error {
value_error (const std::string &&_what):
error (std::move (_what))
{ ; }
};
}
}
template <typename T, class ...Args>

4
tools/json-clean.cpp
View File

@ -5,12 +5,12 @@
* terms of the GNU General Public License as published by the Free Software
* Foundation, either version 3 of the License, or (at your option) any later
* version.
*
*
* libgim is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
*
* You should have received a copy of the GNU General Public License
* along with libgim. If not, see <http://www.gnu.org/licenses/>.
*

26
tools/json-schema.cpp
View File

@ -5,12 +5,12 @@
* terms of the GNU General Public License as published by the Free Software
* Foundation, either version 3 of the License, or (at your option) any later
* version.
*
*
* libgim is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
*
* You should have received a copy of the GNU General Public License
* along with libgim. If not, see <http://www.gnu.org/licenses/>.
*
@ -210,11 +210,11 @@ is_number_valid (const json::tree::number &node,
const json::tree::object &schema) {
typedef bool (*number_validator_t)(const json::tree::number&, const json::tree::node&);
static const map<string, number_validator_t> VALIDATORS = {
{ "minimum", &is_minimum_valid },
{ "maximum", &is_maximum_valid },
{ "exclusiveMinimum", &is_exclusive_minimum_valid },
{ "exclusiveMaximum", &is_exclusive_maximum_valid },
{ "divisibleBy", &is_divisible_by_valid },
{ "minimum", &is_minimum_valid },
{ "maximum", &is_maximum_valid },
{ "exclusiveMinimum", &is_exclusive_minimum_valid },
{ "exclusiveMaximum", &is_exclusive_maximum_valid },
{ "divisibleBy", &is_divisible_by_valid },
};
for (const auto &i: schema) {
@ -340,7 +340,7 @@ is_unique_items_valid (const json::tree::array &node,
if (!constraint.is_boolean ())
throw json::tree::schema_error ("uniqueItems must be a boolean");
if (node.size () < 2)
if (node.size () < 2)
return true;
@ -511,7 +511,7 @@ is_node_valid (const json::tree::node &node,
return is_node_valid (node, referenced->as_object ());
}
if (schema.has ("type") &&
if (schema.has ("type") &&
!is_type_valid (node, schema["type"]))
{
std::cerr << "node type is \"" << type_to_string (node) << "\", expected " << schema["type"] << "\n";
@ -539,7 +539,7 @@ is_node_valid (const json::tree::node &node,
#undef IS_VALID
return false;
/*static const map<string, validator_t> VALIDATORS ({
{ "description", &is_always_valid },
@ -549,7 +549,7 @@ is_node_valid (const json::tree::node &node,
{ "type", &is_type_valid },
});*/
//"required";
@ -577,7 +577,7 @@ main (int argc, char **argv) {
print_usage (argc, argv);
return EXIT_FAILURE;
}
// Load the schema and input
unique_ptr<json::tree::node> schema, input;
try {
@ -593,7 +593,7 @@ main (int argc, char **argv) {
std::cerr << "Schema should be an object\n";
return EXIT_FAILURE;
}
const json::tree::object &schema_object = schema->as_object ();
// Check input is valid

4
tools/json-validate.cpp
View File

@ -23,8 +23,8 @@ main (int argc, char ** argv) {
}
try {
json::tree::parse (boost::filesystem::path (argv[ARG_PATH]));
} catch (json::tree::error &x) {
json::flat::parse (boost::filesystem::path (argv[ARG_PATH]));
} catch (std::exception &x) {
std::cerr << "Error: " << x.what () << std::endl;
return EXIT_FAILURE;
}