mwparserfromhell/mwparserfromhell/parser/tokenizer.h

/*
Tokenizer Header File for MWParserFromHell
Copyright (C) 2012-2013 Ben Kurtovic <ben.kurtovic@verizon.net>

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
of the Software, and to permit persons to whom the Software is furnished to do
so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

#ifndef PY_SSIZE_T_CLEAN
#define PY_SSIZE_T_CLEAN
#endif

#include <Python.h>
#include <math.h>
#include <structmember.h>

#if PY_MAJOR_VERSION >= 3
#define IS_PY3K
#endif

#define malloc PyObject_Malloc
#define free   PyObject_Free

#define DIGITS    "0123456789"
#define HEXDIGITS "0123456789abcdefABCDEF"
#define ALPHANUM  "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"

static const char* MARKERS[] = {
    "{",  "}", "[", "]", "<", ">", "|", "=", "&", "#", "*", ";", ":", "/", "-",
    "!", "\n", ""};

#define NUM_MARKERS 18
#define TEXTBUFFER_BLOCKSIZE 1024
#define MAX_DEPTH 40
#define MAX_CYCLES 100000
#define MAX_ENTITY_SIZE 8

static int route_state = 0;
#define BAD_ROUTE     (route_state)
#define FAIL_ROUTE()  (route_state = 1)
#define RESET_ROUTE() (route_state = 0)

static char** entitydefs;

static PyObject* EMPTY;
static PyObject* NOARGS;
static PyObject* tokens;


/* Tokens */

static PyObject* Text;

static PyObject* TemplateOpen;
static PyObject* TemplateParamSeparator;
static PyObject* TemplateParamEquals;
static PyObject* TemplateClose;

static PyObject* ArgumentOpen;
static PyObject* ArgumentSeparator;
static PyObject* ArgumentClose;

static PyObject* WikilinkOpen;
static PyObject* WikilinkSeparator;
static PyObject* WikilinkClose;

static PyObject* HTMLEntityStart;
static PyObject* HTMLEntityNumeric;
static PyObject* HTMLEntityHex;
static PyObject* HTMLEntityEnd;
static PyObject* HeadingStart;
static PyObject* HeadingEnd;

static PyObject* CommentStart;
static PyObject* CommentEnd;

static PyObject* TagOpenOpen;
static PyObject* TagAttrStart;
static PyObject* TagAttrEquals;
static PyObject* TagAttrQuote;
static PyObject* TagCloseOpen;
static PyObject* TagCloseSelfclose;
static PyObject* TagOpenClose;
static PyObject* TagCloseClose;


/* Local contexts: */

#define LC_TEMPLATE             0x00007
#define LC_TEMPLATE_NAME        0x00001
#define LC_TEMPLATE_PARAM_KEY   0x00002
#define LC_TEMPLATE_PARAM_VALUE 0x00004

#define LC_ARGUMENT             0x00018
#define LC_ARGUMENT_NAME        0x00008
#define LC_ARGUMENT_DEFAULT     0x00010

#define LC_WIKILINK             0x00060
#define LC_WIKILINK_TITLE       0x00020
#define LC_WIKILINK_TEXT        0x00040

#define LC_HEADING              0x01F80
#define LC_HEADING_LEVEL_1      0x00080
#define LC_HEADING_LEVEL_2      0x00100
#define LC_HEADING_LEVEL_3      0x00200
#define LC_HEADING_LEVEL_4      0x00400
#define LC_HEADING_LEVEL_5      0x00800
#define LC_HEADING_LEVEL_6      0x01000

#define LC_COMMENT              0x02000

#define LC_SAFETY_CHECK         0xFC000
#define LC_HAS_TEXT             0x04000
#define LC_FAIL_ON_TEXT         0x08000
#define LC_FAIL_NEXT            0x10000
#define LC_FAIL_ON_LBRACE       0x20000
#define LC_FAIL_ON_RBRACE       0x40000
#define LC_FAIL_ON_EQUALS       0x80000

/* Global contexts: */

#define GL_HEADING 0x1


/* Miscellaneous structs: */

struct Textbuffer {
    Py_ssize_t size;
    Py_UNICODE* data;
    struct Textbuffer* next;
};

struct Stack {
    PyObject* stack;
    int context;
    struct Textbuffer* textbuffer;
    struct Stack* next;
};

typedef struct {
    PyObject* title;
    int level;
} HeadingData;


/* Tokenizer object definition: */

typedef struct {
    PyObject_HEAD
    PyObject* text;         /* text to tokenize */
    struct Stack* topstack; /* topmost stack */
    Py_ssize_t head;        /* current position in text */
    Py_ssize_t length;      /* length of text */
    int global;             /* global context */
    int depth;              /* stack recursion depth */
    int cycles;             /* total number of stack recursions */
} Tokenizer;


/* Macros for accessing Tokenizer data: */

#define Tokenizer_READ(self, delta) (*PyUnicode_AS_UNICODE(Tokenizer_read(self, delta)))
#define Tokenizer_CAN_RECURSE(self) (self->depth < MAX_DEPTH && self->cycles < MAX_CYCLES)


/* Function prototypes: */

static PyObject* Tokenizer_new(PyTypeObject*, PyObject*, PyObject*);
static struct Textbuffer* Textbuffer_new(void);
static void Tokenizer_dealloc(Tokenizer*);
static void Textbuffer_dealloc(struct Textbuffer*);
static int Tokenizer_init(Tokenizer*, PyObject*, PyObject*);
static int Tokenizer_push(Tokenizer*, int);
static PyObject* Textbuffer_render(struct Textbuffer*);
static int Tokenizer_push_textbuffer(Tokenizer*);
static void Tokenizer_delete_top_of_stack(Tokenizer*);
static PyObject* Tokenizer_pop(Tokenizer*);
static PyObject* Tokenizer_pop_keeping_context(Tokenizer*);
static void* Tokenizer_fail_route(Tokenizer*);
static int Tokenizer_write(Tokenizer*, PyObject*);
static int Tokenizer_write_first(Tokenizer*, PyObject*);
static int Tokenizer_write_text(Tokenizer*, Py_UNICODE);
static int Tokenizer_write_all(Tokenizer*, PyObject*);
static int Tokenizer_write_text_then_stack(Tokenizer*, const char*);
static PyObject* Tokenizer_read(Tokenizer*, Py_ssize_t);
static PyObject* Tokenizer_read_backwards(Tokenizer*, Py_ssize_t);
static int Tokenizer_parse_template_or_argument(Tokenizer*);
static int Tokenizer_parse_template(Tokenizer*);
static int Tokenizer_parse_argument(Tokenizer*);
static int Tokenizer_handle_template_param(Tokenizer*);
static int Tokenizer_handle_template_param_value(Tokenizer*);
static PyObject* Tokenizer_handle_template_end(Tokenizer*);
static int Tokenizer_handle_argument_separator(Tokenizer*);
static PyObject* Tokenizer_handle_argument_end(Tokenizer*);
static int Tokenizer_parse_wikilink(Tokenizer*);
static int Tokenizer_handle_wikilink_separator(Tokenizer*);
static PyObject* Tokenizer_handle_wikilink_end(Tokenizer*);
static int Tokenizer_parse_heading(Tokenizer*);
static HeadingData* Tokenizer_handle_heading_end(Tokenizer*);
static int Tokenizer_really_parse_entity(Tokenizer*);
static int Tokenizer_parse_entity(Tokenizer*);
static int Tokenizer_parse_comment(Tokenizer*);
static int Tokenizer_verify_safe(Tokenizer*, int, Py_UNICODE);
static PyObject* Tokenizer_parse(Tokenizer*, int);
static PyObject* Tokenizer_tokenize(Tokenizer*, PyObject*);


/* More structs for creating the Tokenizer type: */

static PyMethodDef
Tokenizer_methods[] = {
    {"tokenize", (PyCFunction) Tokenizer_tokenize, METH_VARARGS,
    "Build a list of tokens from a string of wikicode and return it."},
    {NULL}
};

static PyMemberDef
Tokenizer_members[] = {
    {NULL}
};

static PyMethodDef
module_methods[] = {
    {NULL}
};

static PyTypeObject
TokenizerType = {
    PyObject_HEAD_INIT(NULL)
    0,                                                      /* ob_size */
    "_tokenizer.CTokenizer",                                /* tp_name */
    sizeof(Tokenizer),                                      /* tp_basicsize */
    0,                                                      /* tp_itemsize */
    (destructor) Tokenizer_dealloc,                         /* tp_dealloc */
    0,                                                      /* tp_print */
    0,                                                      /* tp_getattr */
    0,                                                      /* tp_setattr */
    0,                                                      /* tp_compare */
    0,                                                      /* tp_repr */
    0,                                                      /* tp_as_number */
    0,                                                      /* tp_as_sequence */
    0,                                                      /* tp_as_mapping */
    0,                                                      /* tp_hash  */
    0,                                                      /* tp_call */
    0,                                                      /* tp_str */
    0,                                                      /* tp_getattro */
    0,                                                      /* tp_setattro */
    0,                                                      /* tp_as_buffer */
    Py_TPFLAGS_DEFAULT,                                     /* tp_flags */
    "Creates a list of tokens from a string of wikicode.",  /* tp_doc */
    0,                                                      /* tp_traverse */
    0,                                                      /* tp_clear */
    0,                                                      /* tp_richcompare */
    0,                                                      /* tp_weaklistoffset */
    0,                                                      /* tp_iter */
    0,                                                      /* tp_iternext */
    Tokenizer_methods,                                      /* tp_methods */
    Tokenizer_members,                                      /* tp_members */
    0,                                                      /* tp_getset */
    0,                                                      /* tp_base */
    0,                                                      /* tp_dict */
    0,                                                      /* tp_descr_get */
    0,                                                      /* tp_descr_set */
    0,                                                      /* tp_dictoffset */
    (initproc) Tokenizer_init,                              /* tp_init */
    0,                                                      /* tp_alloc */
    Tokenizer_new,                                          /* tp_new */
};