xref: /freebsd/contrib/ncurses/form/fty_regex.c (revision 4cf49a43559ed9fdad601bdcccd2c55963008675)
1 
2 /*
3  * THIS CODE IS SPECIFICALLY EXEMPTED FROM THE NCURSES PACKAGE COPYRIGHT.
4  * You may freely copy it for use as a template for your own field types.
5  * If you develop a field type that might be of general use, please send
6  * it back to the ncurses maintainers for inclusion in the next version.
7  */
8 /***************************************************************************
9 *                                                                          *
10 *  Author : Juergen Pfeifer, juergen.pfeifer@gmx.net                       *
11 *                                                                          *
12 ***************************************************************************/
13 
14 #include "form.priv.h"
15 
16 MODULE_ID("$Id: fty_regex.c,v 1.14 1999/05/16 17:23:38 juergen Exp $")
17 
18 #if HAVE_REGEX_H_FUNCS	/* We prefer POSIX regex */
19 #include <regex.h>
20 
21 typedef struct
22 {
23   regex_t *pRegExp;
24   unsigned long *refCount;
25 } RegExp_Arg;
26 
27 #elif HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
28 #undef RETURN
29 static int reg_errno;
30 
31 static char *RegEx_Init(char *instring)
32 {
33 	reg_errno = 0;
34 	return instring;
35 }
36 
37 static char *RegEx_Error(int code)
38 {
39 	reg_errno = code;
40 	return 0;
41 }
42 
43 #define INIT 		register char *sp = RegEx_Init(instring);
44 #define GETC()		(*sp++)
45 #define PEEKC()		(*sp)
46 #define UNGETC(c)	(--sp)
47 #define RETURN(c)	return(c)
48 #define ERROR(c)	return RegEx_Error(c)
49 
50 #if HAVE_REGEXP_H_FUNCS
51 #include <regexp.h>
52 #else
53 #include <regexpr.h>
54 #endif
55 
56 typedef struct
57 {
58   char *compiled_expression;
59   unsigned long *refCount;
60 } RegExp_Arg;
61 
62 /* Maximum Length we allow for a compiled regular expression */
63 #define MAX_RX_LEN   (2048)
64 #define RX_INCREMENT (256)
65 
66 #endif
67 
68 /*---------------------------------------------------------------------------
69 |   Facility      :  libnform
70 |   Function      :  static void *Make_RegularExpression_Type(va_list * ap)
71 |
72 |   Description   :  Allocate structure for regex type argument.
73 |
74 |   Return Values :  Pointer to argument structure or NULL on error
75 +--------------------------------------------------------------------------*/
76 static void *Make_RegularExpression_Type(va_list * ap)
77 {
78 #if HAVE_REGEX_H_FUNCS
79   char *rx = va_arg(*ap,char *);
80   RegExp_Arg *preg;
81 
82   preg = (RegExp_Arg*)malloc(sizeof(RegExp_Arg));
83   if (preg)
84     {
85       if (((preg->pRegExp = (regex_t*)malloc(sizeof(regex_t))) != (regex_t*)0)
86        && !regcomp(preg->pRegExp,rx,
87 		   (REG_EXTENDED | REG_NOSUB | REG_NEWLINE) ))
88 	{
89 	  preg->refCount = (unsigned long *)malloc(sizeof(unsigned long));
90 	  *(preg->refCount) = 1;
91 	}
92       else
93 	{
94 	  if (preg->pRegExp)
95 	    free(preg->pRegExp);
96 	  free(preg);
97 	  preg = (RegExp_Arg*)0;
98 	}
99     }
100   return((void *)preg);
101 #elif HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
102   char *rx = va_arg(*ap,char *);
103   RegExp_Arg *pArg;
104 
105   pArg = (RegExp_Arg *)malloc(sizeof(RegExp_Arg));
106 
107   if (pArg)
108     {
109       int blen = RX_INCREMENT;
110       pArg->compiled_expression = NULL;
111       pArg->refCount = (unsigned long *)malloc(sizeof(unsigned long));
112       *(pArg->refCount) = 1;
113 
114       do {
115 	char *buf = (char *)malloc(blen);
116 	if (buf)
117 	  {
118 #if HAVE_REGEXP_H_FUNCS
119 	    char *last_pos = compile (rx, buf, &buf[blen], '\0');
120 #else /* HAVE_REGEXPR_H_FUNCS */
121 	    char *last_pos = compile (rx, buf, &buf[blen]);
122 #endif
123 	    if (reg_errno)
124 	      {
125 		free(buf);
126 		if (reg_errno==50)
127 		  blen += RX_INCREMENT;
128 		else
129 		  {
130 		    free(pArg);
131 		    pArg = NULL;
132 		    break;
133 		  }
134 	      }
135 	    else
136 	      {
137 		pArg->compiled_expression = buf;
138 		break;
139 	      }
140 	  }
141       } while( blen <= MAX_RX_LEN );
142     }
143   if (pArg && !pArg->compiled_expression)
144     {
145       free(pArg);
146       pArg = NULL;
147     }
148   return (void *)pArg;
149 #else
150   return 0;
151 #endif
152 }
153 
154 /*---------------------------------------------------------------------------
155 |   Facility      :  libnform
156 |   Function      :  static void *Copy_RegularExpression_Type(
157 |                                      const void * argp)
158 |
159 |   Description   :  Copy structure for regex type argument.
160 |
161 |   Return Values :  Pointer to argument structure or NULL on error.
162 +--------------------------------------------------------------------------*/
163 static void *Copy_RegularExpression_Type(const void * argp)
164 {
165 #if (HAVE_REGEX_H_FUNCS | HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS)
166   const RegExp_Arg *ap = (const RegExp_Arg *)argp;
167   const RegExp_Arg *result = (const RegExp_Arg *)0;
168 
169   if (ap)
170     {
171       *(ap->refCount) += 1;
172       result = ap;
173     }
174   return (void *)result;
175 #else
176   return 0;
177 #endif
178 }
179 
180 /*---------------------------------------------------------------------------
181 |   Facility      :  libnform
182 |   Function      :  static void Free_RegularExpression_Type(void * argp)
183 |
184 |   Description   :  Free structure for regex type argument.
185 |
186 |   Return Values :  -
187 +--------------------------------------------------------------------------*/
188 static void Free_RegularExpression_Type(void * argp)
189 {
190 #if HAVE_REGEX_H_FUNCS | HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
191   RegExp_Arg *ap = (RegExp_Arg *)argp;
192   if (ap)
193     {
194       if (--(*(ap->refCount)) == 0)
195 	{
196 #if HAVE_REGEX_H_FUNCS
197 	  if (ap->pRegExp)
198 	    {
199 	      free(ap->refCount);
200 	      regfree(ap->pRegExp);
201 	    }
202 #elif HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
203 	  if (ap->compiled_expression)
204 	    {
205 	      free(ap->refCount);
206 	      free(ap->compiled_expression);
207 	    }
208 #endif
209 	  free(ap);
210 	}
211     }
212 #endif
213 }
214 
215 /*---------------------------------------------------------------------------
216 |   Facility      :  libnform
217 |   Function      :  static bool Check_RegularExpression_Field(
218 |                                      FIELD * field,
219 |                                      const void  * argp)
220 |
221 |   Description   :  Validate buffer content to be a valid regular expression
222 |
223 |   Return Values :  TRUE  - field is valid
224 |                    FALSE - field is invalid
225 +--------------------------------------------------------------------------*/
226 static bool Check_RegularExpression_Field(FIELD * field, const void  * argp)
227 {
228   bool match = FALSE;
229 #if HAVE_REGEX_H_FUNCS
230   const RegExp_Arg *ap = (const RegExp_Arg*)argp;
231   if (ap && ap->pRegExp)
232     match = (regexec(ap->pRegExp,field_buffer(field,0),0,NULL,0) ? FALSE:TRUE);
233 #elif HAVE_REGEXP_H_FUNCS | HAVE_REGEXPR_H_FUNCS
234   RegExp_Arg *ap = (RegExp_Arg *)argp;
235   if (ap && ap->compiled_expression)
236     match = (step(field_buffer(field,0),ap->compiled_expression) ? TRUE:FALSE);
237 #endif
238   return match;
239 }
240 
241 static FIELDTYPE typeREGEXP = {
242   _HAS_ARGS | _RESIDENT,
243   1,                           /* this is mutable, so we can't be const */
244   (FIELDTYPE *)0,
245   (FIELDTYPE *)0,
246   Make_RegularExpression_Type,
247   Copy_RegularExpression_Type,
248   Free_RegularExpression_Type,
249   Check_RegularExpression_Field,
250   NULL,
251   NULL,
252   NULL
253 };
254 
255 FIELDTYPE* TYPE_REGEXP = &typeREGEXP;
256 
257 /* fty_regex.c ends here */
258