1/****************************************************************************
2 * Copyright 2018,2020 Thomas E. Dickey                                     *
3 * Copyright 1998-2012,2015 Free Software Foundation, Inc.                  *
4 *                                                                          *
5 * Permission is hereby granted, free of charge, to any person obtaining a  *
6 * copy of this software and associated documentation files (the            *
7 * "Software"), to deal in the Software without restriction, including      *
8 * without limitation the rights to use, copy, modify, merge, publish,      *
9 * distribute, distribute with modifications, sublicense, and/or sell       *
10 * copies of the Software, and to permit persons to whom the Software is    *
11 * furnished to do so, subject to the following conditions:                 *
12 *                                                                          *
13 * The above copyright notice and this permission notice shall be included  *
14 * in all copies or substantial portions of the Software.                   *
15 *                                                                          *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
19 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
20 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
21 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
22 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
23 *                                                                          *
24 * Except as contained in this notice, the name(s) of the above copyright   *
25 * holders shall not be used in advertising or otherwise to promote the     *
26 * sale, use or other dealings in this Software without prior written       *
27 * authorization.                                                           *
28 ****************************************************************************/
29
30/***************************************************************************
31*                                                                          *
32*  Author : Juergen Pfeifer                                                *
33*                                                                          *
34***************************************************************************/
35
36#include "form.priv.h"
37
38MODULE_ID("$Id: fty_regex.c,v 1.32 2020/12/12 01:15:37 tom Exp $")
39
40#if HAVE_REGEX_H_FUNCS || HAVE_LIB_PCRE2	/* We prefer POSIX regex */
41
42#if HAVE_PCRE2POSIX_H
43#include <pcre2posix.h>
44#elif HAVE_PCREPOSIX_H
45#include <pcreposix.h>
46#else
47#include <regex.h>
48#endif
49
50typedef struct
51  {
52    regex_t *pRegExp;
53    unsigned long *refCount;
54  }
55RegExp_Arg;
56
57#elif HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
58#undef RETURN
59static int reg_errno;
60
61static char *
62RegEx_Init(char *instring)
63{
64  reg_errno = 0;
65  return instring;
66}
67
68static char *
69RegEx_Error(int code)
70{
71  reg_errno = code;
72  return 0;
73}
74
75#define INIT 		register char *sp = RegEx_Init(instring);
76#define GETC()		(*sp++)
77#define PEEKC()		(*sp)
78#define UNGETC(c)	(--sp)
79#define RETURN(c)	return(c)
80#define ERROR(c)	return RegEx_Error(c)
81
82#if HAVE_REGEXP_H_FUNCS
83#include <regexp.h>
84#else
85#include <regexpr.h>
86#endif
87
88typedef struct
89{
90  char *compiled_expression;
91  unsigned long *refCount;
92}
93RegExp_Arg;
94
95/* Maximum Length we allow for a compiled regular expression */
96#define MAX_RX_LEN   (2048)
97#define RX_INCREMENT (256)
98
99#endif
100
101#if HAVE_REGEX_H_FUNCS | HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
102# define MAYBE_UNUSED
103#else
104# define MAYBE_UNUSED GCC_UNUSED
105#endif
106
107/*---------------------------------------------------------------------------
108|   Facility      :  libnform
109|   Function      :  static void *Generic_RegularExpression_Type(void * arg)
110|
111|   Description   :  Allocate structure for regex type argument.
112|
113|   Return Values :  Pointer to argument structure or NULL on error
114+--------------------------------------------------------------------------*/
115static void *
116Generic_RegularExpression_Type(void *arg MAYBE_UNUSED)
117{
118#if HAVE_REGEX_H_FUNCS
119  char *rx = (char *)arg;
120  RegExp_Arg *preg = (RegExp_Arg *)0;
121
122  if (rx)
123    {
124      preg = typeCalloc(RegExp_Arg, 1);
125
126      if (preg)
127	{
128	  T((T_CREATE("RegExp_Arg %p"), (void *)preg));
129	  if (((preg->pRegExp = typeMalloc(regex_t, 1)) != 0)
130	      && !regcomp(preg->pRegExp, rx,
131			  (REG_EXTENDED | REG_NOSUB | REG_NEWLINE)))
132	    {
133	      T((T_CREATE("regex_t %p"), (void *)preg->pRegExp));
134	      if ((preg->refCount = typeMalloc(unsigned long, 1)) != 0)
135		 *(preg->refCount) = 1;
136	    }
137	  else
138	    {
139	      if (preg->pRegExp)
140		free(preg->pRegExp);
141	      free(preg);
142	      preg = (RegExp_Arg *)0;
143	    }
144	}
145    }
146  return ((void *)preg);
147#elif HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
148  char *rx = (char *)arg;
149  RegExp_Arg *pArg = (RegExp_Arg *)0;
150
151  if (rx)
152    {
153      pArg = typeMalloc(RegExp_Arg, 1);
154
155      if (pArg)
156	{
157	  int blen = RX_INCREMENT;
158
159	  T((T_CREATE("RegExp_Arg %p"), pArg));
160	  pArg->compiled_expression = NULL;
161	  if ((pArg->refCount = typeMalloc(unsigned long, 1)) != 0)
162	     *(pArg->refCount) = 1;
163
164	  do
165	    {
166	      char *buf = typeMalloc(char, blen);
167
168	      if (buf)
169		{
170#if HAVE_REGEXP_H_FUNCS
171		  char *last_pos = compile(rx, buf, &buf[blen], '\0');
172
173#else /* HAVE_REGEXPR_H_FUNCS */
174		  char *last_pos = compile(rx, buf, &buf[blen]);
175#endif
176		  if (reg_errno)
177		    {
178		      free(buf);
179		      if (reg_errno == 50)
180			blen += RX_INCREMENT;
181		      else
182			{
183			  free(pArg);
184			  pArg = NULL;
185			  break;
186			}
187		    }
188		  else
189		    {
190		      pArg->compiled_expression = buf;
191		      break;
192		    }
193		}
194	    }
195	  while (blen <= MAX_RX_LEN);
196	}
197      if (pArg && !pArg->compiled_expression)
198	{
199	  free(pArg);
200	  pArg = NULL;
201	}
202    }
203  return (void *)pArg;
204#else
205  return 0;
206#endif
207}
208
209/*---------------------------------------------------------------------------
210|   Facility      :  libnform
211|   Function      :  static void *Make_RegularExpression_Type(va_list * ap)
212|
213|   Description   :  Allocate structure for regex type argument.
214|
215|   Return Values :  Pointer to argument structure or NULL on error
216+--------------------------------------------------------------------------*/
217static void *
218Make_RegularExpression_Type(va_list *ap)
219{
220  char *rx = va_arg(*ap, char *);
221
222  return Generic_RegularExpression_Type((void *)rx);
223}
224
225/*---------------------------------------------------------------------------
226|   Facility      :  libnform
227|   Function      :  static void *Copy_RegularExpression_Type(
228|                                      const void * argp)
229|
230|   Description   :  Copy structure for regex type argument.
231|
232|   Return Values :  Pointer to argument structure or NULL on error.
233+--------------------------------------------------------------------------*/
234static void *
235Copy_RegularExpression_Type(const void *argp MAYBE_UNUSED)
236{
237#if (HAVE_REGEX_H_FUNCS | HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS)
238  const RegExp_Arg *ap = (const RegExp_Arg *)argp;
239  const RegExp_Arg *result = (const RegExp_Arg *)0;
240
241  if (ap)
242    {
243      *(ap->refCount) += 1;
244      result = ap;
245    }
246  return (void *)result;
247#else
248  return 0;
249#endif
250}
251
252/*---------------------------------------------------------------------------
253|   Facility      :  libnform
254|   Function      :  static void Free_RegularExpression_Type(void * argp)
255|
256|   Description   :  Free structure for regex type argument.
257|
258|   Return Values :  -
259+--------------------------------------------------------------------------*/
260static void
261Free_RegularExpression_Type(void *argp MAYBE_UNUSED)
262{
263#if HAVE_REGEX_H_FUNCS | HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
264  RegExp_Arg *ap = (RegExp_Arg *)argp;
265
266  if (ap)
267    {
268      if (--(*(ap->refCount)) == 0)
269	{
270#if HAVE_REGEX_H_FUNCS
271	  if (ap->pRegExp)
272	    {
273	      free(ap->refCount);
274	      regfree(ap->pRegExp);
275	      free(ap->pRegExp);
276	    }
277#elif HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
278	  if (ap->compiled_expression)
279	    {
280	      free(ap->refCount);
281	      free(ap->compiled_expression);
282	    }
283#endif
284	  free(ap);
285	}
286    }
287#endif
288}
289
290/*---------------------------------------------------------------------------
291|   Facility      :  libnform
292|   Function      :  static bool Check_RegularExpression_Field(
293|                                      FIELD * field,
294|                                      const void  * argp)
295|
296|   Description   :  Validate buffer content to be a valid regular expression
297|
298|   Return Values :  TRUE  - field is valid
299|                    FALSE - field is invalid
300+--------------------------------------------------------------------------*/
301static bool
302Check_RegularExpression_Field(FIELD *field MAYBE_UNUSED,
303			      const void *argp MAYBE_UNUSED)
304{
305  bool match = FALSE;
306
307#if HAVE_REGEX_H_FUNCS
308  const RegExp_Arg *ap = (const RegExp_Arg *)argp;
309
310  if (ap && ap->pRegExp)
311    match = (regexec(ap->pRegExp, field_buffer(field, 0), 0, NULL, 0)
312	     ? FALSE
313	     : TRUE);
314#elif HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
315  RegExp_Arg *ap = (RegExp_Arg *)argp;
316
317  if (ap && ap->compiled_expression)
318    match = (step(field_buffer(field, 0), ap->compiled_expression)
319	     ? TRUE
320	     : FALSE);
321#endif
322  return match;
323}
324
325static FIELDTYPE typeREGEXP =
326{
327  _HAS_ARGS | _RESIDENT,
328  1,				/* this is mutable, so we can't be const */
329  (FIELDTYPE *)0,
330  (FIELDTYPE *)0,
331  Make_RegularExpression_Type,
332  Copy_RegularExpression_Type,
333  Free_RegularExpression_Type,
334  INIT_FT_FUNC(Check_RegularExpression_Field),
335  INIT_FT_FUNC(NULL),
336  INIT_FT_FUNC(NULL),
337  INIT_FT_FUNC(NULL),
338#if NCURSES_INTEROP_FUNCS
339  Generic_RegularExpression_Type
340#endif
341};
342
343FORM_EXPORT_VAR(FIELDTYPE *) TYPE_REGEXP = &typeREGEXP;
344
345#if NCURSES_INTEROP_FUNCS
346/* The next routines are to simplify the use of ncurses from
347   programming languages with restrictions on interop with C level
348   constructs (e.g. variable access or va_list + ellipsis constructs)
349*/
350FORM_EXPORT(FIELDTYPE *)
351_nc_TYPE_REGEXP(void)
352{
353  return TYPE_REGEXP;
354}
355#endif
356
357/* fty_regex.c ends here */
358