xref: /freebsd/contrib/bmake/str.h (revision 00698711dee1d990d3db9c41bf58394e589eecfe)
1 /*	$NetBSD: str.h,v 1.15 2021/12/15 10:57:01 rillig Exp $	*/
2 
3 /*
4  Copyright (c) 2021 Roland Illig <rillig@NetBSD.org>
5  All rights reserved.
6 
7  Redistribution and use in source and binary forms, with or without
8  modification, are permitted provided that the following conditions
9  are met:
10 
11  1. Redistributions of source code must retain the above copyright
12     notice, this list of conditions and the following disclaimer.
13  2. Redistributions in binary form must reproduce the above copyright
14     notice, this list of conditions and the following disclaimer in the
15     documentation and/or other materials provided with the distribution.
16 
17  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS
21  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 
31 /*
32  * Memory-efficient string handling.
33  */
34 
35 
36 /* A read-only string that may need to be freed after use. */
37 typedef struct FStr {
38 	const char *str;
39 	void *freeIt;
40 } FStr;
41 
42 /* A read-only range of a character array, NOT null-terminated. */
43 typedef struct Substring {
44 	const char *start;
45 	const char *end;
46 } Substring;
47 
48 /*
49  * Builds a string, only allocating memory if the string is different from the
50  * expected string.
51  */
52 typedef struct LazyBuf {
53 	char *data;
54 	size_t len;
55 	size_t cap;
56 	const char *expected;
57 } LazyBuf;
58 
59 /* The result of splitting a string into words. */
60 typedef struct Words {
61 	char **words;
62 	size_t len;
63 	void *freeIt;
64 } Words;
65 
66 /* The result of splitting a string into words. */
67 typedef struct SubstringWords {
68 	Substring *words;
69 	size_t len;
70 	void *freeIt;
71 } SubstringWords;
72 
73 
74 MAKE_INLINE FStr
75 FStr_Init(const char *str, void *freeIt)
76 {
77 	FStr fstr;
78 	fstr.str = str;
79 	fstr.freeIt = freeIt;
80 	return fstr;
81 }
82 
83 /* Return a string that is the sole owner of str. */
84 MAKE_INLINE FStr
85 FStr_InitOwn(char *str)
86 {
87 	return FStr_Init(str, str);
88 }
89 
90 /* Return a string that refers to the shared str. */
91 MAKE_INLINE FStr
92 FStr_InitRefer(const char *str)
93 {
94 	return FStr_Init(str, NULL);
95 }
96 
97 MAKE_INLINE void
98 FStr_Done(FStr *fstr)
99 {
100 	free(fstr->freeIt);
101 #ifdef CLEANUP
102 	fstr->str = NULL;
103 	fstr->freeIt = NULL;
104 #endif
105 }
106 
107 
108 MAKE_STATIC Substring
109 Substring_Init(const char *start, const char *end)
110 {
111 	Substring sub;
112 
113 	sub.start = start;
114 	sub.end = end;
115 	return sub;
116 }
117 
118 MAKE_INLINE Substring
119 Substring_InitStr(const char *str)
120 {
121 	return Substring_Init(str, str + strlen(str));
122 }
123 
124 MAKE_STATIC size_t
125 Substring_Length(Substring sub)
126 {
127 	return (size_t)(sub.end - sub.start);
128 }
129 
130 MAKE_STATIC bool
131 Substring_IsEmpty(Substring sub)
132 {
133 	return sub.start == sub.end;
134 }
135 
136 MAKE_INLINE bool
137 Substring_Equals(Substring sub, const char *str)
138 {
139 	size_t len = strlen(str);
140 	return Substring_Length(sub) == len &&
141 	       memcmp(sub.start, str, len) == 0;
142 }
143 
144 MAKE_INLINE bool
145 Substring_Eq(Substring sub, Substring str)
146 {
147 	size_t len = Substring_Length(sub);
148 	return len == Substring_Length(str) &&
149 	       memcmp(sub.start, str.start, len) == 0;
150 }
151 
152 MAKE_STATIC Substring
153 Substring_Sub(Substring sub, size_t start, size_t end)
154 {
155 	assert(start <= Substring_Length(sub));
156 	assert(end <= Substring_Length(sub));
157 	return Substring_Init(sub.start + start, sub.start + end);
158 }
159 
160 MAKE_STATIC bool
161 Substring_HasPrefix(Substring sub, Substring prefix)
162 {
163 	return Substring_Length(sub) >= Substring_Length(prefix) &&
164 	       memcmp(sub.start, prefix.start, Substring_Length(prefix)) == 0;
165 }
166 
167 MAKE_STATIC bool
168 Substring_HasSuffix(Substring sub, Substring suffix)
169 {
170 	size_t suffixLen = Substring_Length(suffix);
171 	return Substring_Length(sub) >= suffixLen &&
172 	       memcmp(sub.end - suffixLen, suffix.start, suffixLen) == 0;
173 }
174 
175 /* Returns an independent, null-terminated copy of the substring. */
176 MAKE_STATIC FStr
177 Substring_Str(Substring sub)
178 {
179 	if (Substring_IsEmpty(sub))
180 		return FStr_InitRefer("");
181 	return FStr_InitOwn(bmake_strsedup(sub.start, sub.end));
182 }
183 
184 MAKE_STATIC const char *
185 Substring_SkipFirst(Substring sub, char ch)
186 {
187 	const char *p;
188 
189 	for (p = sub.start; p != sub.end; p++)
190 		if (*p == ch)
191 			return p + 1;
192 	return sub.start;
193 }
194 
195 MAKE_STATIC const char *
196 Substring_LastIndex(Substring sub, char ch)
197 {
198 	const char *p;
199 
200 	for (p = sub.end; p != sub.start; p--)
201 		if (p[-1] == ch)
202 			return p - 1;
203 	return NULL;
204 }
205 
206 MAKE_STATIC Substring
207 Substring_Dirname(Substring pathname)
208 {
209 	const char *p;
210 
211 	for (p = pathname.end; p != pathname.start; p--)
212 		if (p[-1] == '/')
213 			return Substring_Init(pathname.start, p - 1);
214 	return Substring_InitStr(".");
215 }
216 
217 MAKE_STATIC Substring
218 Substring_Basename(Substring pathname)
219 {
220 	const char *p;
221 
222 	for (p = pathname.end; p != pathname.start; p--)
223 		if (p[-1] == '/')
224 			return Substring_Init(p, pathname.end);
225 	return pathname;
226 }
227 
228 
229 MAKE_STATIC void
230 LazyBuf_Init(LazyBuf *buf, const char *expected)
231 {
232 	buf->data = NULL;
233 	buf->len = 0;
234 	buf->cap = 0;
235 	buf->expected = expected;
236 }
237 
238 MAKE_INLINE void
239 LazyBuf_Done(LazyBuf *buf)
240 {
241 	free(buf->data);
242 }
243 
244 MAKE_STATIC void
245 LazyBuf_Add(LazyBuf *buf, char ch)
246 {
247 
248 	if (buf->data != NULL) {
249 		if (buf->len == buf->cap) {
250 			buf->cap *= 2;
251 			buf->data = bmake_realloc(buf->data, buf->cap);
252 		}
253 		buf->data[buf->len++] = ch;
254 
255 	} else if (ch == buf->expected[buf->len]) {
256 		buf->len++;
257 		return;
258 
259 	} else {
260 		buf->cap = buf->len + 16;
261 		buf->data = bmake_malloc(buf->cap);
262 		memcpy(buf->data, buf->expected, buf->len);
263 		buf->data[buf->len++] = ch;
264 	}
265 }
266 
267 MAKE_STATIC void
268 LazyBuf_AddStr(LazyBuf *buf, const char *str)
269 {
270 	const char *p;
271 
272 	for (p = str; *p != '\0'; p++)
273 		LazyBuf_Add(buf, *p);
274 }
275 
276 MAKE_STATIC void
277 LazyBuf_AddBytesBetween(LazyBuf *buf, const char *start, const char *end)
278 {
279 	const char *p;
280 
281 	for (p = start; p != end; p++)
282 		LazyBuf_Add(buf, *p);
283 }
284 
285 MAKE_INLINE void
286 LazyBuf_AddSubstring(LazyBuf *buf, Substring sub)
287 {
288 	LazyBuf_AddBytesBetween(buf, sub.start, sub.end);
289 }
290 
291 MAKE_STATIC Substring
292 LazyBuf_Get(const LazyBuf *buf)
293 {
294 	const char *start = buf->data != NULL ? buf->data : buf->expected;
295 	return Substring_Init(start, start + buf->len);
296 }
297 
298 /*
299  * Returns the content of the buffer as a newly allocated string.
300  *
301  * See LazyBuf_Get to avoid unnecessary memory allocations.
302  */
303 MAKE_STATIC FStr
304 LazyBuf_DoneGet(LazyBuf *buf)
305 {
306 	if (buf->data != NULL) {
307 		LazyBuf_Add(buf, '\0');
308 		return FStr_InitOwn(buf->data);
309 	}
310 	return Substring_Str(LazyBuf_Get(buf));
311 }
312 
313 
314 Words Str_Words(const char *, bool);
315 
316 MAKE_INLINE void
317 Words_Free(Words w)
318 {
319 	free(w.words);
320 	free(w.freeIt);
321 }
322 
323 
324 SubstringWords Substring_Words(const char *, bool);
325 
326 MAKE_INLINE void
327 SubstringWords_Init(SubstringWords *w)
328 {
329 	w->words = NULL;
330 	w->len = 0;
331 	w->freeIt = NULL;
332 }
333 
334 MAKE_INLINE void
335 SubstringWords_Free(SubstringWords w)
336 {
337 	free(w.words);
338 	free(w.freeIt);
339 }
340 
341 
342 char *str_concat2(const char *, const char *);
343 char *str_concat3(const char *, const char *, const char *);
344 
345 bool Str_Match(const char *, const char *);
346 
347 void Str_Intern_Init(void);
348 void Str_Intern_End(void);
349 const char *Str_Intern(const char *);
350