xref: /PHP-7.3/ext/pcre/pcre2lib/pcre2_newline.c (revision a5bc5aed)
1 /*************************************************
2 *      Perl-Compatible Regular Expressions       *
3 *************************************************/
4 
5 /* PCRE is a library of functions to support regular expressions whose syntax
6 and semantics are as close as possible to those of the Perl 5 language.
7 
8                        Written by Philip Hazel
9      Original API code Copyright (c) 1997-2012 University of Cambridge
10          New API code Copyright (c) 2016 University of Cambridge
11 
12 -----------------------------------------------------------------------------
13 Redistribution and use in source and binary forms, with or without
14 modification, are permitted provided that the following conditions are met:
15 
16     * Redistributions of source code must retain the above copyright notice,
17       this list of conditions and the following disclaimer.
18 
19     * Redistributions in binary form must reproduce the above copyright
20       notice, this list of conditions and the following disclaimer in the
21       documentation and/or other materials provided with the distribution.
22 
23     * Neither the name of the University of Cambridge nor the names of its
24       contributors may be used to endorse or promote products derived from
25       this software without specific prior written permission.
26 
27 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
28 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
31 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 POSSIBILITY OF SUCH DAMAGE.
38 -----------------------------------------------------------------------------
39 */
40 
41 
42 /* This module contains internal functions for testing newlines when more than
43 one kind of newline is to be recognized. When a newline is found, its length is
44 returned. In principle, we could implement several newline "types", each
45 referring to a different set of newline characters. At present, PCRE2 supports
46 only NLTYPE_FIXED, which gets handled without these functions, NLTYPE_ANYCRLF,
47 and NLTYPE_ANY. The full list of Unicode newline characters is taken from
48 http://unicode.org/unicode/reports/tr18/. */
49 
50 
51 #ifdef HAVE_CONFIG_H
52 #include "config.h"
53 #endif
54 
55 #include "pcre2_internal.h"
56 
57 
58 
59 /*************************************************
60 *      Check for newline at given position       *
61 *************************************************/
62 
63 /* This function is called only via the IS_NEWLINE macro, which does so only
64 when the newline type is NLTYPE_ANY or NLTYPE_ANYCRLF. The case of a fixed
65 newline (NLTYPE_FIXED) is handled inline. It is guaranteed that the code unit
66 pointed to by ptr is less than the end of the string.
67 
68 Arguments:
69   ptr          pointer to possible newline
70   type         the newline type
71   endptr       pointer to the end of the string
72   lenptr       where to return the length
73   utf          TRUE if in utf mode
74 
75 Returns:       TRUE or FALSE
76 */
77 
78 BOOL
PRIV(is_newline)79 PRIV(is_newline)(PCRE2_SPTR ptr, uint32_t type, PCRE2_SPTR endptr,
80   uint32_t *lenptr, BOOL utf)
81 {
82 uint32_t c;
83 
84 #ifdef SUPPORT_UNICODE
85 if (utf) { GETCHAR(c, ptr); } else c = *ptr;
86 #else
87 (void)utf;
88 c = *ptr;
89 #endif  /* SUPPORT_UNICODE */
90 
91 if (type == NLTYPE_ANYCRLF) switch(c)
92   {
93   case CHAR_LF:
94   *lenptr = 1;
95   return TRUE;
96 
97   case CHAR_CR:
98   *lenptr = (ptr < endptr - 1 && ptr[1] == CHAR_LF)? 2 : 1;
99   return TRUE;
100 
101   default:
102   return FALSE;
103   }
104 
105 /* NLTYPE_ANY */
106 
107 else switch(c)
108   {
109 #ifdef EBCDIC
110   case CHAR_NEL:
111 #endif
112   case CHAR_LF:
113   case CHAR_VT:
114   case CHAR_FF:
115   *lenptr = 1;
116   return TRUE;
117 
118   case CHAR_CR:
119   *lenptr = (ptr < endptr - 1 && ptr[1] == CHAR_LF)? 2 : 1;
120   return TRUE;
121 
122 #ifndef EBCDIC
123 #if PCRE2_CODE_UNIT_WIDTH == 8
124   case CHAR_NEL:
125   *lenptr = utf? 2 : 1;
126   return TRUE;
127 
128   case 0x2028:   /* LS */
129   case 0x2029:   /* PS */
130   *lenptr = 3;
131   return TRUE;
132 
133 #else  /* 16-bit or 32-bit code units */
134   case CHAR_NEL:
135   case 0x2028:   /* LS */
136   case 0x2029:   /* PS */
137   *lenptr = 1;
138   return TRUE;
139 #endif
140 #endif /* Not EBCDIC */
141 
142   default:
143   return FALSE;
144   }
145 }
146 
147 
148 
149 /*************************************************
150 *     Check for newline at previous position     *
151 *************************************************/
152 
153 /* This function is called only via the WAS_NEWLINE macro, which does so only
154 when the newline type is NLTYPE_ANY or NLTYPE_ANYCRLF. The case of a fixed
155 newline (NLTYPE_FIXED) is handled inline. It is guaranteed that the initial
156 value of ptr is greater than the start of the string that is being processed.
157 
158 Arguments:
159   ptr          pointer to possible newline
160   type         the newline type
161   startptr     pointer to the start of the string
162   lenptr       where to return the length
163   utf          TRUE if in utf mode
164 
165 Returns:       TRUE or FALSE
166 */
167 
168 BOOL
PRIV(was_newline)169 PRIV(was_newline)(PCRE2_SPTR ptr, uint32_t type, PCRE2_SPTR startptr,
170   uint32_t *lenptr, BOOL utf)
171 {
172 uint32_t c;
173 ptr--;
174 
175 #ifdef SUPPORT_UNICODE
176 if (utf)
177   {
178   BACKCHAR(ptr);
179   GETCHAR(c, ptr);
180   }
181 else c = *ptr;
182 #else
183 (void)utf;
184 c = *ptr;
185 #endif  /* SUPPORT_UNICODE */
186 
187 if (type == NLTYPE_ANYCRLF) switch(c)
188   {
189   case CHAR_LF:
190   *lenptr = (ptr > startptr && ptr[-1] == CHAR_CR)? 2 : 1;
191   return TRUE;
192 
193   case CHAR_CR:
194   *lenptr = 1;
195   return TRUE;
196 
197   default:
198   return FALSE;
199   }
200 
201 /* NLTYPE_ANY */
202 
203 else switch(c)
204   {
205   case CHAR_LF:
206   *lenptr = (ptr > startptr && ptr[-1] == CHAR_CR)? 2 : 1;
207   return TRUE;
208 
209 #ifdef EBCDIC
210   case CHAR_NEL:
211 #endif
212   case CHAR_VT:
213   case CHAR_FF:
214   case CHAR_CR:
215   *lenptr = 1;
216   return TRUE;
217 
218 #ifndef EBCDIC
219 #if PCRE2_CODE_UNIT_WIDTH == 8
220   case CHAR_NEL:
221   *lenptr = utf? 2 : 1;
222   return TRUE;
223 
224   case 0x2028:   /* LS */
225   case 0x2029:   /* PS */
226   *lenptr = 3;
227   return TRUE;
228 
229 #else /* 16-bit or 32-bit code units */
230   case CHAR_NEL:
231   case 0x2028:   /* LS */
232   case 0x2029:   /* PS */
233   *lenptr = 1;
234   return TRUE;
235 #endif
236 #endif /* Not EBCDIC */
237 
238   default:
239   return FALSE;
240   }
241 }
242 
243 /* End of pcre2_newline.c */
244