ucx/string.h@1e51558b9d09
ucx/string.h
Sun, 17 May 2015 17:31:32 +0200
- author
- Mike Becker <universe@uap-core.de>
- date
- Sun, 17 May 2015 17:31:32 +0200
- changeset 192
- 1e51558b9d09
- parent 183
- 6a694f8f0084
- child 210
- 6bdb04d87236
- permissions
- -rw-r--r--
updated copyright notice + added files for upcoming AVL tree implementation
1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2015 Olaf Wintermann. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28 /**
29 * Bounded string implementation.
30 *
31 * The UCX strings (<code>sstr_t</code>) provide an alternative to C strings.
32 * The main difference to C strings is, that <code>sstr_t</code> does <b>not
33 * need to be <code>NULL</code>-terminated</b>. Instead the length is stored
34 * within the structure.
35 *
36 * When using <code>sstr_t</code>, developers must be full aware of what type
37 * of string (<code>NULL</code>-terminated) or not) they are using, when
38 * accessing the <code>char* ptr</code> directly.
39 *
40 * The UCX string module provides some common string functions, known from
41 * standard libc, working with <code>sstr_t</code>.
42 *
43 * @file string.h
44 * @author Mike Becker
45 * @author Olaf Wintermann
46 */
48 #ifndef UCX_STRING_H
49 #define UCX_STRING_H
51 #include "ucx.h"
52 #include "allocator.h"
53 #include <stddef.h>
55 /** Shortcut for a <code>sstr_t struct</code> literal. */
56 #define ST(s) { (char*)s, sizeof(s)-1 }
58 /** Shortcut for the conversion of a C string to a <code>sstr_t</code>. */
59 #define S(s) sstrn((char*)s, sizeof(s)-1)
61 #ifdef __cplusplus
62 extern "C" {
63 #endif
65 /**
66 * The UCX string structure.
67 */
68 typedef struct {
69 /** A reference to the string (<b>not necessarily <code>NULL</code>
70 * -terminated</b>) */
71 char *ptr;
72 /** The length of the string */
73 size_t length;
74 } sstr_t;
76 /**
77 * Creates a new sstr_t based on a C string.
78 *
79 * The length is implicitly inferred by using a call to <code>strlen()</code>.
80 *
81 * <b>Note:</b> the sstr_t will hold a <i>reference</i> to the C string. If you
82 * do want a copy, use sstrdup() on the return value of this function.
83 *
84 * @param cstring the C string to wrap
85 * @return a new sstr_t containing the C string
86 *
87 * @see sstrn()
88 */
89 sstr_t sstr(char *cstring);
91 /**
92 * Creates a new sstr_t of the specified length based on a C string.
93 *
94 * <b>Note:</b> the sstr_t will hold a <i>reference</i> to the C string. If you
95 * do want a copy, use sstrdup() on the return value of this function.
96 *
97 * @param cstring the C string to wrap
98 * @param length the length of the string
99 * @return a new sstr_t containing the C string
100 *
101 * @see sstr()
102 * @see S()
103 */
104 sstr_t sstrn(char *cstring, size_t length);
107 /**
108 * Returns the cumulated length of all specified strings.
109 *
110 * At least one string must be specified.
111 *
112 * <b>Attention:</b> if the count argument does not match the count of the
113 * specified strings, the behavior is undefined.
114 *
115 * @param count the total number of specified strings (so at least 1)
116 * @param string the first string
117 * @param ... all other strings
118 * @return the cumulated length of all strings
119 */
120 size_t sstrnlen(size_t count, sstr_t string, ...);
122 /**
123 * Concatenates two or more strings.
124 *
125 * The resulting string will be allocated by standard <code>malloc()</code>.
126 * So developers <b>MUST</b> pass the sstr_t.ptr to <code>free()</code>.
127 *
128 * The sstr_t.ptr of the return value will <i>always</i> be <code>NULL</code>-
129 * terminated.
130 *
131 * @param count the total number of strings to concatenate
132 * @param s1 first string
133 * @param s2 second string
134 * @param ... all remaining strings
135 * @return the concatenated string
136 */
137 sstr_t sstrcat(size_t count, sstr_t s1, sstr_t s2, ...);
139 /**
140 * Concatenates two or more strings using an UcxAllocator.
141 *
142 * See sstrcat() for details.
143 *
144 * @param a the allocator to use
145 * @param count the total number of strings to concatenate
146 * @param s1 first string
147 * @param s2 second string
148 * @param ... all remaining strings
149 * @return the concatenated string
150 */
151 sstr_t sstrcat_a(UcxAllocator *a, size_t count, sstr_t s1, sstr_t s2, ...);
154 /**
155 * Returns a substring starting at the specified location.
156 *
157 * <b>Attention:</b> the new string references the same memory area as the
158 * input string and will <b>NOT</b> be <code>NULL</code>-terminated.
159 * Use sstrdup() to get a copy.
160 *
161 * @param string input string
162 * @param start start location of the substring
163 * @return a substring of <code>string</code> starting at <code>start</code>
164 *
165 * @see sstrsubsl()
166 * @see sstrchr()
167 */
168 sstr_t sstrsubs(sstr_t string, size_t start);
170 /**
171 * Returns a substring with a maximum length starting at the specified location.
172 *
173 * <b>Attention:</b> the new string references the same memory area as the
174 * input string and will <b>NOT</b> be <code>NULL</code>-terminated.
175 * Use sstrdup() to get a copy.
176 *
177 * @param string input string
178 * @param start start location of the substring
179 * @param length the maximum length of the substring
180 * @return a substring of <code>string</code> starting at <code>start</code>
181 * with a maximum length of <code>length</code>
182 *
183 * @see sstrsubs()
184 * @see sstrchr()
185 */
186 sstr_t sstrsubsl(sstr_t string, size_t start, size_t length);
188 /**
189 * Returns a substring starting at the location of the first occurrence of the
190 * specified character.
191 *
192 * If the string does not contain the character, an empty string is returned.
193 *
194 * @param string the string where to locate the character
195 * @param chr the character to locate
196 * @return a substring starting at the first location of <code>chr</code>
197 *
198 * @see sstrsubs()
199 */
200 sstr_t sstrchr(sstr_t string, int chr);
202 /**
203 * Returns a substring starting at the location of the last occurrence of the
204 * specified character.
205 *
206 * If the string does not contain the character, an empty string is returned.
207 *
208 * @param string the string where to locate the character
209 * @param chr the character to locate
210 * @return a substring starting at the last location of <code>chr</code>
211 *
212 * @see sstrsubs()
213 */
214 sstr_t sstrrchr(sstr_t string, int chr);
216 /**
217 * Splits a string into parts by using a delimiter string.
218 *
219 * This function will return <code>NULL</code>, if one of the following happens:
220 * <ul>
221 * <li>the string length is zero</li>
222 * <li>the delimeter length is zero</li>
223 * <li>the string equals the delimeter</li>
224 * <li>memory allocation fails</li>
225 * </ul>
226 *
227 * The integer referenced by <code>count</code> is used as input and determines
228 * the maximum size of the resulting array, i.e. the maximum count of splits to
229 * perform + 1.
230 *
231 * The integer referenced by <code>count</code> is also used as output and is
232 * set to
233 * <ul>
234 * <li>-2, on memory allocation errors</li>
235 * <li>-1, if either the string or the delimiter is an empty string</li>
236 * <li>0, if the string equals the delimiter</li>
237 * <li>1, if the string does not contain the delimiter</li>
238 * <li>the count of array items, otherwise</li>
239 * </ul>
240 *
241 * If the string starts with the delimiter, the first item of the resulting
242 * array will be an empty string.
243 *
244 * If the string ends with the delimiter and the maximum list size is not
245 * exceeded, the last array item will be an empty string.
246 *
247 * <b>Attention:</b> The array pointer <b>AND</b> all sstr_t.ptr of the array
248 * items must be manually passed to <code>free()</code>. Use sstrsplit_a() with
249 * an allocator to managed memory, to avoid this.
250 *
251 * @param string the string to split
252 * @param delim the delimiter string
253 * @param count IN: the maximum size of the resulting array (0 = no limit),
254 * OUT: the actual size of the array
255 * @return a sstr_t array containing the split strings or
256 * <code>NULL</code> on error
257 *
258 * @see sstrsplit_a()
259 */
260 sstr_t* sstrsplit(sstr_t string, sstr_t delim, ssize_t *count);
262 /**
263 * Performing sstrsplit() using an UcxAllocator.
264 *
265 * <i>Read the description of sstrsplit() for details.</i>
266 *
267 * The memory for the sstr_t.ptr pointers of the array items and the memory for
268 * the sstr_t array itself are allocated by using the UcxAllocator.malloc()
269 * function.
270 *
271 * <b>Note:</b> the allocator is not used for memory that is freed within the
272 * same call of this function (locally scoped variables).
273 *
274 * @param allocator the UcxAllocator used for allocating memory
275 * @param string the string to split
276 * @param delim the delimiter string
277 * @param count IN: the maximum size of the resulting array (0 = no limit),
278 * OUT: the actual size of the array
279 * @return a sstr_t array containing the split strings or
280 * <code>NULL</code> on error
281 *
282 * @see sstrsplit()
283 */
284 sstr_t* sstrsplit_a(UcxAllocator *allocator, sstr_t string, sstr_t delim,
285 ssize_t *count);
287 /**
288 * Compares two UCX strings with standard <code>memcmp()</code>.
289 *
290 * At first it compares the sstr_t.length attribute of the two strings. The
291 * <code>memcmp()</code> function is called, if and only if the lengths match.
292 *
293 * @param s1 the first string
294 * @param s2 the second string
295 * @return -1, if the length of s1 is less than the length of s2 or 1, if the
296 * length of s1 is greater than the length of s2 or the result of
297 * <code>memcmp()</code> otherwise (i.e. 0 if the strings match)
298 */
299 int sstrcmp(sstr_t s1, sstr_t s2);
301 /**
302 * Compares two UCX strings ignoring the case.
303 *
304 * At first it compares the sstr_t.length attribute of the two strings. If and
305 * only if the lengths match, both strings are compared char by char ignoring
306 * the case.
307 *
308 * @param s1 the first string
309 * @param s2 the second string
310 * @return -1, if the length of s1 is less than the length of s2 or 1, if the
311 * length of s1 is greater than the length of s2 or the difference between the
312 * first two differing characters otherwise (i.e. 0 if the strings match and
313 * no characters differ)
314 */
315 int sstrcasecmp(sstr_t s1, sstr_t s2);
317 /**
318 * Creates a duplicate of the specified string.
319 *
320 * The new sstr_t will contain a copy allocated by standard
321 * <code>malloc()</code>. So developers <b>MUST</b> pass the sstr_t.ptr to
322 * <code>free()</code>.
323 *
324 * The sstr_t.ptr of the return value will <i>always</i> be <code>NULL</code>-
325 * terminated.
326 *
327 * @param string the string to duplicate
328 * @return a duplicate of the string
329 * @see sstrdup_a()
330 */
331 sstr_t sstrdup(sstr_t string);
333 /**
334 * Creates a duplicate of the specified string using an UcxAllocator.
335 *
336 * The new sstr_t will contain a copy allocated by the allocators
337 * ucx_allocator_malloc function. So it is implementation depended, whether the
338 * returned sstr_t.ptr pointer must be passed to the allocators
339 * ucx_allocator_free function manually.
340 *
341 * The sstr_t.ptr of the return value will <i>always</i> be <code>NULL</code>-
342 * terminated.
343 *
344 * @param allocator a valid instance of an UcxAllocator
345 * @param string the string to duplicate
346 * @return a duplicate of the string
347 * @see sstrdup()
348 */
349 sstr_t sstrdup_a(UcxAllocator *allocator, sstr_t string);
351 /**
352 * Omits leading and trailing spaces.
353 *
354 * This function returns a new sstr_t containing a trimmed version of the
355 * specified string.
356 *
357 * <b>Note:</b> the new sstr_t references the same memory, thus you
358 * <b>MUST NOT</b> pass the sstr_t.ptr of the return value to
359 * <code>free()</code>. It is also highly recommended to avoid assignments like
360 * <code>mystr = sstrtrim(mystr);</code> as you lose the reference to the
361 * source string. Assignments of this type are only permitted, if the
362 * sstr_t.ptr of the source string does not need to be freed or if another
363 * reference to the source string exists.
364 *
365 * @param string the string that shall be trimmed
366 * @return a new sstr_t containing the trimmed string
367 */
368 sstr_t sstrtrim(sstr_t string);
370 /**
371 * Checks, if a string has a specific prefix.
372 * @param string the string to check
373 * @param prefix the prefix the string should have
374 * @return 1, if and only if the string has the specified prefix, 0 otherwise
375 */
376 int sstrprefix(sstr_t string, sstr_t prefix);
378 /**
379 * Checks, if a string has a specific suffix.
380 * @param string the string to check
381 * @param suffix the suffix the string should have
382 * @return 1, if and only if the string has the specified suffix, 0 otherwise
383 */
384 int sstrsuffix(sstr_t string, sstr_t suffix);
386 #ifdef __cplusplus
387 }
388 #endif
390 #endif /* UCX_STRING_H */
