1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2024 Mike Becker, 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 * @file properties.h
30 * @brief Interface for parsing data from properties files.
31 * @author Mike Becker
32 * @author Olaf Wintermann
33 * @copyright 2-Clause BSD License
34 */
35
36 #ifndef UCX_PROPERTIES_H
37 #define UCX_PROPERTIES_H
38
39 #include "common.h"
40 #include "string.h"
41 #include "map.h"
42 #include "buffer.h"
43
44 #include <stdio.h>
45 #include <string.h>
46
47 #ifdef __cplusplus
48 extern "C" {
49 #endif
50
51 /**
52 * Configures the expected characters for the properties parser.
53 */
54 struct cx_properties_config_s {
55 /**
56 * The key/value delimiter that shall be used.
57 * This is '=' by default.
58 */
59 char delimiter;
60
61 /**
62 * The character, when appearing at the end of a line, continues that line.
63 * This is '\' by default.
64 */
65 // char continuation; // TODO: line continuation in properties
66
67 /**
68 * The first comment character.
69 * This is '#' by default.
70 */
71 char comment1;
72
73 /**
74 * The second comment character.
75 * This is not set by default.
76 */
77 char comment2;
78
79 /**
80 * The third comment character.
81 * This is not set by default.
82 */
83 char comment3;
84 };
85
86 /**
87 * Typedef for the properties config.
88 */
89 typedef struct cx_properties_config_s CxPropertiesConfig;
90
91 /**
92 * Default properties configuration.
93 */
94 extern const CxPropertiesConfig cx_properties_config_default;
95
96 /**
97 * Status codes for the properties interface.
98 */
99 enum cx_properties_status {
100 /**
101 * Everything is fine.
102 */
103 CX_PROPERTIES_NO_ERROR,
104 /**
105 * The input buffer does not contain more data.
106 */
107 CX_PROPERTIES_NO_DATA,
108 /**
109 * The input ends unexpectedly.
110 *
111 * This either happens when the last line does not terminate with a line
112 * break, or when the input ends with a parsed key but no value.
113 */
114 CX_PROPERTIES_INCOMPLETE_DATA,
115 /**
116 * Not used as a status and never returned by any function.
117 *
118 * You can use this enumerator to check for all "good" status results
119 * by checking if the status is less than @c CX_PROPERTIES_OK.
120 *
121 * A "good" status means, that you can refill data and continue parsing.
122 */
123 CX_PROPERTIES_OK,
124 /**
125 * Input buffer is @c NULL.
126 */
127 CX_PROPERTIES_NULL_INPUT,
128 /**
129 * The line contains a delimiter, but no key.
130 */
131 CX_PROPERTIES_INVALID_EMPTY_KEY,
132 /**
133 * The line contains data, but no delimiter.
134 */
135 CX_PROPERTIES_INVALID_MISSING_DELIMITER,
136 /**
137 * More internal buffer was needed, but could not be allocated.
138 */
139 CX_PROPERTIES_BUFFER_ALLOC_FAILED,
140 /**
141 * Initializing the properties source failed.
142 *
143 * @see cx_properties_read_init_func
144 */
145 CX_PROPERTIES_READ_INIT_FAILED,
146 /**
147 * Reading from a properties source failed.
148 *
149 * @see cx_properties_read_func
150 */
151 CX_PROPERTIES_READ_FAILED,
152 /**
153 * Sinking a k/v-pair failed.
154 *
155 * @see cx_properties_sink_func
156 */
157 CX_PROPERTIES_SINK_FAILED,
158 };
159
160 /**
161 * Typedef for the properties status enum.
162 */
163 typedef enum cx_properties_status CxPropertiesStatus;
164
165 /**
166 * Interface for working with properties data.
167 */
168 struct cx_properties_s {
169 /**
170 * The configuration.
171 */
172 CxPropertiesConfig config;
173
174 /**
175 * The text input buffer.
176 */
177 CxBuffer input;
178
179 /**
180 * Internal buffer.
181 */
182 CxBuffer buffer;
183 };
184
185 /**
186 * Typedef for the properties interface.
187 */
188 typedef struct cx_properties_s CxProperties;
189
190
191 /**
192 * Typedef for a properties sink.
193 */
194 typedef struct cx_properties_sink_s CxPropertiesSink;
195
196 /**
197 * A function that consumes a k/v-pair in a sink.
198 *
199 * The sink could be e.g. a map and the sink function would be calling
200 * a map function to store the k/v-pair.
201 *
202 * @param prop the properties interface that wants to sink a k/v-pair
203 * @param sink the sink
204 * @param key the key
205 * @param value the value
206 * @retval zero success
207 * @retval non-zero sinking the k/v-pair failed
208 */
209 cx_attr_nonnull
210 typedef int(*cx_properties_sink_func)(
211 CxProperties *prop,
212 CxPropertiesSink *sink,
213 cxstring key,
214 cxstring value
215 );
216
217 /**
218 * Defines a sink for k/v-pairs.
219 */
220 struct cx_properties_sink_s {
221 /**
222 * The sink object.
223 */
224 void *sink;
225 /**
226 * Optional custom data.
227 */
228 void *data;
229 /**
230 * A function for consuming k/v-pairs into the sink.
231 */
232 cx_properties_sink_func sink_func;
233 };
234
235
236 /**
237 * Typedef for a properties source.
238 */
239 typedef struct cx_properties_source_s CxPropertiesSource;
240
241 /**
242 * A function that reads data from a source.
243 *
244 * When the source is depleted, implementations SHALL provide an empty
245 * string in the @p target and return zero.
246 * A non-zero return value is only permitted in case of an error.
247 *
248 * The meaning of the optional parameters is implementation-dependent.
249 *
250 * @param prop the properties interface that wants to read from the source
251 * @param src the source
252 * @param target a string buffer where the read data shall be stored
253 * @retval zero success
254 * @retval non-zero reading the data failed
255 */
256 cx_attr_nonnull
257 typedef int(*cx_properties_read_func)(
258 CxProperties *prop,
259 CxPropertiesSource *src,
260 cxstring *target
261 );
262
263 /**
264 * A function that may initialize additional memory for the source.
265 *
266 * @param prop the properties interface that wants to read from the source
267 * @param src the source
268 * @retval zero initialization was successful
269 * @retval non-zero otherwise
270 */
271 cx_attr_nonnull
272 typedef int(*cx_properties_read_init_func)(
273 CxProperties *prop,
274 CxPropertiesSource *src
275 );
276
277 /**
278 * A function that cleans memory initialized by the read_init_func.
279 *
280 * @param prop the properties interface that wants to read from the source
281 * @param src the source
282 */
283 cx_attr_nonnull
284 typedef void(*cx_properties_read_clean_func)(
285 CxProperties *prop,
286 CxPropertiesSource *src
287 );
288
289 /**
290 * Defines a properties source.
291 */
292 struct cx_properties_source_s {
293 /**
294 * The source object.
295 *
296 * For example a file stream or a string.
297 */
298 void *src;
299 /**
300 * Optional additional data pointer.
301 */
302 void *data_ptr;
303 /**
304 * Optional size information.
305 */
306 size_t data_size;
307 /**
308 * A function that reads data from the source.
309 */
310 cx_properties_read_func read_func;
311 /**
312 * Optional function that may prepare the source for reading data.
313 */
314 cx_properties_read_init_func read_init_func;
315 /**
316 * Optional function that cleans additional memory allocated by the
317 * read_init_func.
318 */
319 cx_properties_read_clean_func read_clean_func;
320 };
321
322 /**
323 * Initialize a properties interface.
324 *
325 * @param prop the properties interface
326 * @param config the properties configuration
327 * @see cxPropertiesInitDefault()
328 */
329 cx_attr_nonnull
330 void cxPropertiesInit(CxProperties *prop, CxPropertiesConfig config);
331
332 /**
333 * Destroys the properties interface.
334 *
335 * @note Even when you are certain that you did not use the interface in a
336 * way that caused a memory allocation, you should call this function anyway.
337 * Future versions of the library might add features that need additional memory
338 * and you really don't want to search the entire code where you might need
339 * add call to this function.
340 *
341 * @param prop the properties interface
342 */
343 cx_attr_nonnull
344 void cxPropertiesDestroy(CxProperties *prop);
345
346 /**
347 * Destroys and re-initializes the properties interface.
348 *
349 * You might want to use this, to reset the parser after
350 * encountering a syntax error.
351 *
352 * @param prop the properties interface
353 */
354 cx_attr_nonnull
355 static inline void cxPropertiesReset(CxProperties *prop) {
356 CxPropertiesConfig config = prop->config;
357 cxPropertiesDestroy(prop);
358 cxPropertiesInit(prop, config);
359 }
360
361 /**
362 * Initialize a properties parser with the default configuration.
363 *
364 * @param prop (@c CxProperties*) the properties interface
365 * @see cxPropertiesInit()
366 */
367 #define cxPropertiesInitDefault(prop) \
368 cxPropertiesInit(prop, cx_properties_config_default)
369
370 /**
371 * Fills the input buffer with data.
372 *
373 * After calling this function, you can parse the data by calling
374 * cxPropertiesNext().
375 *
376 * @remark The properties interface tries to avoid allocations.
377 * When you use this function and cxPropertiesNext() interleaving,
378 * no allocations are performed. However, you must not free the
379 * pointer to the data in that case. When you invoke the fill
380 * function more than once before calling cxPropertiesNext(),
381 * the additional data is appended - inevitably leading to
382 * an allocation of a new buffer and copying the previous contents.
383 *
384 * @param prop the properties interface
385 * @param buf a pointer to the data
386 * @param len the length of the data
387 * @retval zero success
388 * @retval non-zero a memory allocation was necessary but failed
389 * @see cxPropertiesFill()
390 */
391 cx_attr_nonnull
392 cx_attr_access_r(2, 3)
393 int cxPropertiesFilln(
394 CxProperties *prop,
395 const char *buf,
396 size_t len
397 );
398
399 #ifdef __cplusplus
400 } // extern "C"
401 cx_attr_nonnull
402 static inline int cxPropertiesFill(
403 CxProperties *prop,
404 cxstring str
405 ) {
406 return cxPropertiesFilln(prop, str.ptr, str.length);
407 }
408
409 cx_attr_nonnull
410 static inline int cxPropertiesFill(
411 CxProperties *prop,
412 cxmutstr str
413 ) {
414 return cxPropertiesFilln(prop, str.ptr, str.length);
415 }
416
417 cx_attr_nonnull
418 cx_attr_cstr_arg(2)
419 static inline int cxPropertiesFill(
420 CxProperties *prop,
421 const char *str
422 ) {
423 return cxPropertiesFilln(prop, str, strlen(str));
424 }
425
426 extern "C" {
427 #else // __cplusplus
428 /**
429 * Fills the input buffer with data.
430 *
431 * After calling this function, you can parse the data by calling
432 * cxPropertiesNext().
433 *
434 * @attention The properties interface tries to avoid allocations.
435 * When you use this function and cxPropertiesNext() interleaving,
436 * no allocations are performed. However, you must not free the
437 * pointer to the data in that case. When you invoke the fill
438 * function more than once before calling cxPropertiesNext(),
439 * the additional data is appended - inevitably leading to
440 * an allocation of a new buffer and copying the previous contents.
441 *
442 * @param prop the properties interface
443 * @param str the text to fill in
444 * @retval zero success
445 * @retval non-zero a memory allocation was necessary but failed
446 * @see cxPropertiesFilln()
447 */
448 #define cxPropertiesFill(prop, str) _Generic((str), \
449 cxstring: cx_properties_fill_cxstr, \
450 cxmutstr: cx_properties_fill_mutstr, \
451 char*: cx_properties_fill_str, \
452 const char*: cx_properties_fill_str) \
453 (prop, str)
454
455 /**
456 * @copydoc cxPropertiesFill()
457 */
458 cx_attr_nonnull
459 static inline int cx_properties_fill_cxstr(
460 CxProperties *prop,
461 cxstring str
462 ) {
463 return cxPropertiesFilln(prop, str.ptr, str.length);
464 }
465
466 /**
467 * @copydoc cxPropertiesFill()
468 */
469 cx_attr_nonnull
470 static inline int cx_properties_fill_mutstr(
471 CxProperties *prop,
472 cxmutstr str
473 ) {
474 return cxPropertiesFilln(prop, str.ptr, str.length);
475 }
476
477 /**
478 * @copydoc cxPropertiesFill()
479 */
480 cx_attr_nonnull
481 cx_attr_cstr_arg(2)
482 static inline int cx_properties_fill_str(
483 CxProperties *prop,
484 const char *str
485 ) {
486 return cxPropertiesFilln(prop, str, strlen(str));
487 }
488 #endif
489
490 /**
491 * Specifies stack memory that shall be used as internal buffer.
492 *
493 * @param prop the properties interface
494 * @param buf a pointer to stack memory
495 * @param capacity the capacity of the stack memory
496 */
497 cx_attr_nonnull
498 void cxPropertiesUseStack(
499 CxProperties *prop,
500 char *buf,
501 size_t capacity
502 );
503
504 /**
505 * Retrieves the next key/value-pair.
506 *
507 * This function returns zero as long as there are key/value-pairs found.
508 * If no more key/value-pairs are found, #CX_PROPERTIES_NO_DATA is returned.
509 *
510 * When an incomplete line is encountered, #CX_PROPERTIES_INCOMPLETE_DATA is
511 * returned, and you can add more data with #cxPropertiesFill().
512 *
513 * @remark The incomplete line will be stored in an internal buffer, which is
514 * allocated on the heap, by default. If you want to avoid allocations,
515 * you can specify sufficient space with cxPropertiesUseStack() after
516 * initialization with cxPropertiesInit().
517 *
518 * @attention The returned strings will point into a buffer that might not be
519 * available later. It is strongly recommended to copy the strings for further
520 * use.
521 *
522 * @param prop the properties interface
523 * @param key a pointer to the cxstring that shall contain the property name
524 * @param value a pointer to the cxstring that shall contain the property value
525 * @retval CX_PROPERTIES_NO_ERROR (zero) a key/value pair was found
526 * @retval CX_PROPERTIES_NO_DATA there is no (more) data in the input buffer
527 * @retval CX_PROPERTIES_INCOMPLETE_DATA the data in the input buffer is incomplete
528 * (fill more data and try again)
529 * @retval CX_PROPERTIES_NULL_INPUT the input buffer was never filled
530 * @retval CX_PROPERTIES_INVALID_EMPTY_KEY the properties data contains an illegal empty key
531 * @retval CX_PROPERTIES_INVALID_MISSING_DELIMITER the properties data contains a line without delimiter
532 * @retval CX_PROPERTIES_BUFFER_ALLOC_FAILED an internal allocation was necessary but failed
533 */
534 cx_attr_nonnull
535 cx_attr_nodiscard
536 CxPropertiesStatus cxPropertiesNext(
537 CxProperties *prop,
538 cxstring *key,
539 cxstring *value
540 );
541
542 /**
543 * Creates a properties sink for an UCX map.
544 *
545 * The values stored in the map will be pointers to strings allocated
546 * by #cx_strdup_a().
547 * The default stdlib allocator will be used, unless you specify a custom
548 * allocator in the optional @c data of the sink.
549 *
550 * @param map the map that shall consume the k/v-pairs.
551 * @return the sink
552 * @see cxPropertiesLoad()
553 */
554 cx_attr_nonnull
555 cx_attr_nodiscard
556 CxPropertiesSink cxPropertiesMapSink(CxMap *map);
557
558 /**
559 * Creates a properties source based on an UCX string.
560 *
561 * @param str the string
562 * @return the properties source
563 * @see cxPropertiesLoad()
564 */
565 cx_attr_nodiscard
566 CxPropertiesSource cxPropertiesStringSource(cxstring str);
567
568 /**
569 * Creates a properties source based on C string with the specified length.
570 *
571 * @param str the string
572 * @param len the length
573 * @return the properties source
574 * @see cxPropertiesLoad()
575 */
576 cx_attr_nonnull
577 cx_attr_nodiscard
578 cx_attr_access_r(1, 2)
579 CxPropertiesSource cxPropertiesCstrnSource(const char *str, size_t len);
580
581 /**
582 * Creates a properties source based on a C string.
583 *
584 * The length will be determined with strlen(), so the string MUST be
585 * zero-terminated.
586 *
587 * @param str the string
588 * @return the properties source
589 * @see cxPropertiesLoad()
590 */
591 cx_attr_nonnull
592 cx_attr_nodiscard
593 cx_attr_cstr_arg(1)
594 CxPropertiesSource cxPropertiesCstrSource(const char *str);
595
596 /**
597 * Creates a properties source based on an FILE.
598 *
599 * @param file the file
600 * @param chunk_size how many bytes may be read in one operation
601 *
602 * @return the properties source
603 * @see cxPropertiesLoad()
604 */
605 cx_attr_nonnull
606 cx_attr_nodiscard
607 cx_attr_access_r(1)
608 CxPropertiesSource cxPropertiesFileSource(FILE *file, size_t chunk_size);
609
610
611 /**
612 * Loads properties data from a source and transfers it to a sink.
613 *
614 * This function tries to read as much data from the source as possible.
615 * When the source was completely consumed and at least on k/v-pair was found,
616 * the return value will be #CX_PROPERTIES_NO_ERROR.
617 * When the source was consumed but no k/v-pairs were found, the return value
618 * will be #CX_PROPERTIES_NO_DATA.
619 * The other result codes apply, according to their description.
620 *
621 * @param prop the properties interface
622 * @param sink the sink
623 * @param source the source
624 * @retval CX_PROPERTIES_NO_ERROR (zero) a key/value pair was found
625 * @retval CX_PROPERTIES_READ_INIT_FAILED initializing the source failed
626 * @retval CX_PROPERTIES_READ_FAILED reading from the source failed
627 * @retval CX_PROPERTIES_SINK_FAILED sinking the properties into the sink failed
628 * @retval CX_PROPERTIES_NO_DATA the source did not provide any key/value pairs
629 * @retval CX_PROPERTIES_INVALID_EMPTY_KEY the properties data contains an illegal empty key
630 * @retval CX_PROPERTIES_INVALID_MISSING_DELIMITER the properties data contains a line without delimiter
631 * @retval CX_PROPERTIES_BUFFER_ALLOC_FAILED an internal allocation was necessary but failed
632 */
633 cx_attr_nonnull
634 CxPropertiesStatus cxPropertiesLoad(
635 CxProperties *prop,
636 CxPropertiesSink sink,
637 CxPropertiesSource source
638 );
639
640 #ifdef __cplusplus
641 } // extern "C"
642 #endif
643
644 #endif // UCX_PROPERTIES_H
645