xref: /lighttpd1.4/src/buffer.c (revision 0c1aed55)
1 #include "first.h"
2 
3 #include "buffer.h"
4 
5 #include <stdlib.h>
6 #include <string.h>
7 
8 static const char hex_chars[] = "0123456789abcdef";
9 
10 /**
11  * init the buffer
12  *
13  */
14 
15 buffer* buffer_init(void) {
16 	buffer *b;
17 
18 	b = malloc(sizeof(*b));
19 	force_assert(b);
20 
21 	b->ptr = NULL;
22 	b->size = 0;
23 	b->used = 0;
24 
25 	return b;
26 }
27 
28 buffer *buffer_init_buffer(const buffer *src) {
29 	buffer *b = buffer_init();
30 	buffer_copy_buffer(b, src);
31 	return b;
32 }
33 
34 buffer *buffer_init_string(const char *str) {
35 	buffer *b = buffer_init();
36 	buffer_copy_string(b, str);
37 	return b;
38 }
39 
40 void buffer_free(buffer *b) {
41 	if (NULL == b) return;
42 
43 	free(b->ptr);
44 	free(b);
45 }
46 
47 void buffer_reset(buffer *b) {
48 	if (NULL == b) return;
49 
50 	/* limit don't reuse buffer larger than ... bytes */
51 	if (b->size > BUFFER_MAX_REUSE_SIZE) {
52 		free(b->ptr);
53 		b->ptr = NULL;
54 		b->size = 0;
55 	} else if (b->size > 0) {
56 		b->ptr[0] = '\0';
57 	}
58 
59 	b->used = 0;
60 }
61 
62 void buffer_move(buffer *b, buffer *src) {
63 	buffer tmp;
64 
65 	if (NULL == b) {
66 		buffer_reset(src);
67 		return;
68 	}
69 	buffer_reset(b);
70 	if (NULL == src) return;
71 
72 	tmp = *src; *src = *b; *b = tmp;
73 }
74 
75 #define BUFFER_PIECE_SIZE 64
76 static size_t buffer_align_size(size_t size) {
77 	size_t align = BUFFER_PIECE_SIZE - (size % BUFFER_PIECE_SIZE);
78 	/* overflow on unsinged size_t is defined to wrap around */
79 	if (size + align < size) return size;
80 	return size + align;
81 }
82 
83 /* make sure buffer is at least "size" big. discard old data */
84 static void buffer_alloc(buffer *b, size_t size) {
85 	force_assert(NULL != b);
86 	if (0 == size) size = 1;
87 
88 	if (size <= b->size) return;
89 
90 	if (NULL != b->ptr) free(b->ptr);
91 
92 	b->used = 0;
93 	b->size = buffer_align_size(size);
94 	b->ptr = malloc(b->size);
95 
96 	force_assert(NULL != b->ptr);
97 }
98 
99 /* make sure buffer is at least "size" big. keep old data */
100 static void buffer_realloc(buffer *b, size_t size) {
101 	force_assert(NULL != b);
102 	if (0 == size) size = 1;
103 
104 	if (size <= b->size) return;
105 
106 	b->size = buffer_align_size(size);
107 	b->ptr = realloc(b->ptr, b->size);
108 
109 	force_assert(NULL != b->ptr);
110 }
111 
112 
113 char* buffer_string_prepare_copy(buffer *b, size_t size) {
114 	force_assert(NULL != b);
115 	force_assert(size + 1 > size);
116 
117 	buffer_alloc(b, size + 1);
118 
119 	b->used = 1;
120 	b->ptr[0] = '\0';
121 
122 	return b->ptr;
123 }
124 
125 char* buffer_string_prepare_append(buffer *b, size_t size) {
126 	force_assert(NULL !=  b);
127 
128 	if (buffer_string_is_empty(b)) {
129 		return buffer_string_prepare_copy(b, size);
130 	} else {
131 		size_t req_size = b->used + size;
132 
133 		/* not empty, b->used already includes a terminating 0 */
134 		force_assert(req_size >= b->used);
135 
136 		/* check for overflow: unsigned overflow is defined to wrap around */
137 		force_assert(req_size >= b->used);
138 
139 		buffer_realloc(b, req_size);
140 
141 		return b->ptr + b->used - 1;
142 	}
143 }
144 
145 void buffer_string_set_length(buffer *b, size_t len) {
146 	force_assert(NULL != b);
147 	force_assert(len + 1 > len);
148 
149 	buffer_realloc(b, len + 1);
150 
151 	b->used = len + 1;
152 	b->ptr[len] = '\0';
153 }
154 
155 void buffer_commit(buffer *b, size_t size)
156 {
157 	force_assert(NULL != b);
158 	force_assert(b->size > 0);
159 
160 	if (0 == b->used) b->used = 1;
161 
162 	if (size > 0) {
163 		/* check for overflow: unsigned overflow is defined to wrap around */
164 		force_assert(b->used + size > b->used);
165 
166 		force_assert(b->used + size <= b->size);
167 		b->used += size;
168 	}
169 
170 	b->ptr[b->used - 1] = '\0';
171 }
172 
173 void buffer_copy_string(buffer *b, const char *s) {
174 	buffer_copy_string_len(b, s, NULL != s ? strlen(s) : 0);
175 }
176 
177 void buffer_copy_string_len(buffer *b, const char *s, size_t s_len) {
178 	force_assert(NULL != b);
179 	force_assert(NULL != s || s_len == 0);
180 
181 	buffer_string_prepare_copy(b, s_len);
182 
183 	if (0 != s_len) memcpy(b->ptr, s, s_len);
184 
185 	buffer_commit(b, s_len);
186 }
187 
188 void buffer_copy_buffer(buffer *b, const buffer *src) {
189 	if (NULL == src || 0 == src->used) {
190 		buffer_string_prepare_copy(b, 0);
191 		b->used = 0; /* keep special empty state for now */
192 	} else {
193 		buffer_copy_string_len(b, src->ptr, buffer_string_length(src));
194 	}
195 }
196 
197 void buffer_append_string(buffer *b, const char *s) {
198 	buffer_append_string_len(b, s, NULL != s ? strlen(s) : 0);
199 }
200 
201 /**
202  * append a string to the end of the buffer
203  *
204  * the resulting buffer is terminated with a '\0'
205  * s is treated as a un-terminated string (a \0 is handled a normal character)
206  *
207  * @param b a buffer
208  * @param s the string
209  * @param s_len size of the string (without the terminating \0)
210  */
211 
212 void buffer_append_string_len(buffer *b, const char *s, size_t s_len) {
213 	char *target_buf;
214 
215 	force_assert(NULL != b);
216 	force_assert(NULL != s || s_len == 0);
217 
218 	target_buf = buffer_string_prepare_append(b, s_len);
219 
220 	if (0 == s_len) return; /* nothing to append */
221 
222 	memcpy(target_buf, s, s_len);
223 
224 	buffer_commit(b, s_len);
225 }
226 
227 void buffer_append_string_buffer(buffer *b, const buffer *src) {
228 	if (NULL == src) {
229 		buffer_append_string_len(b, NULL, 0);
230 	} else {
231 		buffer_append_string_len(b, src->ptr, buffer_string_length(src));
232 	}
233 }
234 
235 void buffer_append_uint_hex(buffer *b, uintmax_t value) {
236 	char *buf;
237 	unsigned int shift = 0;
238 
239 	{
240 		uintmax_t copy = value;
241 		do {
242 			copy >>= 8;
243 			shift += 8; /* counting bits */
244 		} while (0 != copy);
245 	}
246 
247 	buf = buffer_string_prepare_append(b, shift >> 2); /*nibbles (4 bits)*/
248 	buffer_commit(b, shift >> 2); /* will fill below */
249 
250 	while (shift > 0) {
251 		shift -= 4;
252 		*(buf++) = hex_chars[(value >> shift) & 0x0F];
253 	}
254 }
255 
256 static char* utostr(char * const buf_end, uintmax_t val) {
257 	char *cur = buf_end;
258 	do {
259 		int mod = val % 10;
260 		val /= 10;
261 		/* prepend digit mod */
262 		*(--cur) = (char) ('0' + mod);
263 	} while (0 != val);
264 	return cur;
265 }
266 
267 static char* itostr(char * const buf_end, intmax_t val) {
268 	/* absolute value not defined for INTMAX_MIN, but can take absolute
269 	 * value of any negative number via twos complement cast to unsigned.
270 	 * negative sign is prepended after (now unsigned) value is converted
271 	 * to string */
272 	uintmax_t uval = val >= 0 ? (uintmax_t)val : ((uintmax_t)~val) + 1;
273 	char *cur = utostr(buf_end, uval);
274 	if (val < 0) *(--cur) = '-';
275 
276 	return cur;
277 }
278 
279 void buffer_append_int(buffer *b, intmax_t val) {
280 	char buf[LI_ITOSTRING_LENGTH];
281 	char* const buf_end = buf + sizeof(buf);
282 	char *str;
283 
284 	force_assert(NULL != b);
285 
286 	str = itostr(buf_end, val);
287 	force_assert(buf_end > str && str >= buf);
288 
289 	buffer_append_string_len(b, str, buf_end - str);
290 }
291 
292 void buffer_copy_int(buffer *b, intmax_t val) {
293 	force_assert(NULL != b);
294 
295 	b->used = 0;
296 	buffer_append_int(b, val);
297 }
298 
299 void buffer_append_strftime(buffer *b, const char *format, const struct tm *tm) {
300 	size_t r;
301 	char* buf;
302 	force_assert(NULL != b);
303 	force_assert(NULL != tm);
304 
305 	if (NULL == format || '\0' == format[0]) {
306 		/* empty format */
307 		buffer_string_prepare_append(b, 0);
308 		return;
309 	}
310 
311 	buf = buffer_string_prepare_append(b, 255);
312 	r = strftime(buf, buffer_string_space(b), format, tm);
313 
314 	/* 0 (in some apis buffer_string_space(b)) signals the string may have
315 	 * been too small; but the format could also just have lead to an empty
316 	 * string
317 	 */
318 	if (0 == r || r >= buffer_string_space(b)) {
319 		/* give it a second try with a larger string */
320 		buf = buffer_string_prepare_append(b, 4095);
321 		r = strftime(buf, buffer_string_space(b), format, tm);
322 	}
323 
324 	if (r >= buffer_string_space(b)) r = 0;
325 
326 	buffer_commit(b, r);
327 }
328 
329 
330 void li_itostrn(char *buf, size_t buf_len, intmax_t val) {
331 	char p_buf[LI_ITOSTRING_LENGTH];
332 	char* const p_buf_end = p_buf + sizeof(p_buf);
333 	char* str = p_buf_end - 1;
334 	*str = '\0';
335 
336 	str = itostr(str, val);
337 	force_assert(p_buf_end > str && str >= p_buf);
338 
339 	force_assert(buf_len >= (size_t) (p_buf_end - str));
340 	memcpy(buf, str, p_buf_end - str);
341 }
342 
343 void li_utostrn(char *buf, size_t buf_len, uintmax_t val) {
344 	char p_buf[LI_ITOSTRING_LENGTH];
345 	char* const p_buf_end = p_buf + sizeof(p_buf);
346 	char* str = p_buf_end - 1;
347 	*str = '\0';
348 
349 	str = utostr(str, val);
350 	force_assert(p_buf_end > str && str >= p_buf);
351 
352 	force_assert(buf_len >= (size_t) (p_buf_end - str));
353 	memcpy(buf, str, p_buf_end - str);
354 }
355 
356 char int2hex(char c) {
357 	return hex_chars[(c & 0x0F)];
358 }
359 
360 /* converts hex char (0-9, A-Z, a-z) to decimal.
361  * returns 0xFF on invalid input.
362  */
363 char hex2int(unsigned char hex) {
364 	unsigned char value = hex - '0';
365 	if (value > 9) {
366 		hex |= 0x20; /* to lower case */
367 		value = hex - 'a' + 10;
368 		if (value < 10) value = 0xff;
369 	}
370 	if (value > 15) value = 0xff;
371 
372 	return value;
373 }
374 
375 /**
376  * check if two buffer contain the same data
377  *
378  * HISTORY: this function was pretty much optimized, but didn't handled
379  * alignment properly.
380  */
381 
382 int buffer_is_equal(const buffer *a, const buffer *b) {
383 	force_assert(NULL != a && NULL != b);
384 
385 	if (a->used != b->used) return 0;
386 	if (a->used == 0) return 1;
387 
388 	return (0 == memcmp(a->ptr, b->ptr, a->used));
389 }
390 
391 int buffer_is_equal_string(const buffer *a, const char *s, size_t b_len) {
392 	force_assert(NULL != a && NULL != s);
393 	force_assert(b_len + 1 > b_len);
394 
395 	if (a->used != b_len + 1) return 0;
396 	if (0 != memcmp(a->ptr, s, b_len)) return 0;
397 	if ('\0' != a->ptr[a->used-1]) return 0;
398 
399 	return 1;
400 }
401 
402 /* buffer_is_equal_caseless_string(b, CONST_STR_LEN("value")) */
403 int buffer_is_equal_caseless_string(const buffer *a, const char *s, size_t b_len) {
404 	force_assert(NULL != a);
405 	if (a->used != b_len + 1) return 0;
406 	force_assert('\0' == a->ptr[a->used - 1]);
407 
408 	return (0 == strcasecmp(a->ptr, s));
409 }
410 
411 int buffer_caseless_compare(const char *a, size_t a_len, const char *b, size_t b_len) {
412 	size_t const len = (a_len < b_len) ? a_len : b_len;
413 	size_t i;
414 
415 	for (i = 0; i < len; ++i) {
416 		unsigned char ca = a[i], cb = b[i];
417 		if (ca == cb) continue;
418 
419 		/* always lowercase for transitive results */
420 		if (ca >= 'A' && ca <= 'Z') ca |= 32;
421 		if (cb >= 'A' && cb <= 'Z') cb |= 32;
422 
423 		if (ca == cb) continue;
424 		return ((int)ca) - ((int)cb);
425 	}
426 	if (a_len == b_len) return 0;
427 	return a_len < b_len ? -1 : 1;
428 }
429 
430 int buffer_is_equal_right_len(const buffer *b1, const buffer *b2, size_t len) {
431 	/* no len -> equal */
432 	if (len == 0) return 1;
433 
434 	/* len > 0, but empty buffers -> not equal */
435 	if (b1->used == 0 || b2->used == 0) return 0;
436 
437 	/* buffers too small -> not equal */
438 	if (b1->used - 1 < len || b2->used - 1 < len) return 0;
439 
440 	return 0 == memcmp(b1->ptr + b1->used - 1 - len, b2->ptr + b2->used - 1 - len, len);
441 }
442 
443 void li_tohex(char *buf, size_t buf_len, const char *s, size_t s_len) {
444 	size_t i;
445 	force_assert(2 * s_len > s_len);
446 	force_assert(2 * s_len < buf_len);
447 
448 	for (i = 0; i < s_len; i++) {
449 		buf[2*i] = hex_chars[(s[i] >> 4) & 0x0F];
450 		buf[2*i+1] = hex_chars[s[i] & 0x0F];
451 	}
452 	buf[2*s_len] = '\0';
453 }
454 
455 void buffer_copy_string_hex(buffer *b, const char *in, size_t in_len) {
456 	/* overflow protection */
457 	force_assert(in_len * 2 > in_len);
458 
459 	buffer_string_set_length(b, 2 * in_len);
460 	li_tohex(b->ptr, buffer_string_length(b)+1, in, in_len);
461 }
462 
463 
464 void buffer_substr_replace (buffer * const b, const size_t offset,
465                             const size_t len, const buffer * const replace)
466 {
467     const size_t blen = buffer_string_length(b);
468     const size_t rlen = buffer_string_length(replace);
469 
470     if (rlen > len) {
471         buffer_string_set_length(b, blen-len+rlen);
472         memmove(b->ptr+offset+rlen, b->ptr+offset+len, blen-offset-len);
473     }
474 
475     memcpy(b->ptr+offset, replace->ptr, rlen);
476 
477     if (rlen < len) {
478         memmove(b->ptr+offset+rlen, b->ptr+offset+len, blen-offset-len);
479         buffer_string_set_length(b, blen-len+rlen);
480     }
481 }
482 
483 
484 /* everything except: ! ( ) * - . 0-9 A-Z _ a-z */
485 static const char encoded_chars_rel_uri_part[] = {
486 	/*
487 	0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
488 	*/
489 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  00 -  0F control chars */
490 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  10 -  1F */
491 	1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1,  /*  20 -  2F space " # $ % & ' + , / */
492 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1,  /*  30 -  3F : ; < = > ? */
493 	1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  40 -  4F @ */
494 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0,  /*  50 -  5F [ \ ] ^ */
495 	1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  60 -  6F ` */
496 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1,  /*  70 -  7F { | } DEL */
497 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  80 -  8F */
498 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  90 -  9F */
499 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  A0 -  AF */
500 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  B0 -  BF */
501 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  C0 -  CF */
502 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  D0 -  DF */
503 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  E0 -  EF */
504 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  F0 -  FF */
505 };
506 
507 /* everything except: ! ( ) * - . / 0-9 A-Z _ a-z */
508 static const char encoded_chars_rel_uri[] = {
509 	/*
510 	0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
511 	*/
512 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  00 -  0F control chars */
513 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  10 -  1F */
514 	1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0,  /*  20 -  2F space " # $ % & ' + , */
515 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1,  /*  30 -  3F : ; < = > ? */
516 	1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  40 -  4F @ */
517 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0,  /*  50 -  5F [ \ ] ^ */
518 	1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  60 -  6F ` */
519 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1,  /*  70 -  7F { | } DEL */
520 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  80 -  8F */
521 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  90 -  9F */
522 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  A0 -  AF */
523 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  B0 -  BF */
524 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  C0 -  CF */
525 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  D0 -  DF */
526 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  E0 -  EF */
527 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  F0 -  FF */
528 };
529 
530 static const char encoded_chars_html[] = {
531 	/*
532 	0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
533 	*/
534 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  00 -  0F control chars */
535 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  10 -  1F */
536 	0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0,  /*  20 -  2F " & ' */
537 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0,  /*  30 -  3F < > */
538 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  40 -  4F */
539 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  50 -  5F */
540 	1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  60 -  6F ` */
541 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,  /*  70 -  7F DEL */
542 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  80 -  8F */
543 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  90 -  9F */
544 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  A0 -  AF */
545 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  B0 -  BF */
546 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  C0 -  CF */
547 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  D0 -  DF */
548 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  E0 -  EF */
549 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  F0 -  FF */
550 };
551 
552 static const char encoded_chars_minimal_xml[] = {
553 	/*
554 	0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
555 	*/
556 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  00 -  0F control chars */
557 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  10 -  1F */
558 	0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0,  /*  20 -  2F " & ' */
559 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0,  /*  30 -  3F < > */
560 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  40 -  4F */
561 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  50 -  5F */
562 	1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  60 -  6F ` */
563 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,  /*  70 -  7F DEL */
564 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  80 -  8F */
565 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  90 -  9F */
566 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  A0 -  AF */
567 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  B0 -  BF */
568 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  C0 -  CF */
569 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  D0 -  DF */
570 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  E0 -  EF */
571 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  F0 -  FF */
572 };
573 
574 static const char encoded_chars_hex[] = {
575 	/*
576 	0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
577 	*/
578 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  00 -  0F control chars */
579 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  10 -  1F */
580 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  20 -  2F */
581 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  30 -  3F */
582 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  40 -  4F */
583 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  50 -  5F */
584 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  60 -  6F */
585 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  70 -  7F */
586 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  80 -  8F */
587 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  90 -  9F */
588 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  A0 -  AF */
589 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  B0 -  BF */
590 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  C0 -  CF */
591 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  D0 -  DF */
592 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  E0 -  EF */
593 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /*  F0 -  FF */
594 };
595 
596 static const char encoded_chars_http_header[] = {
597 	/*
598 	0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
599 	*/
600 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0,  /*  00 -  0F */
601 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  10 -  1F */
602 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  20 -  2F */
603 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  30 -  3F */
604 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  40 -  4F */
605 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  50 -  5F */
606 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  60 -  6F */
607 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  70 -  7F */
608 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  80 -  8F */
609 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  90 -  9F */
610 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  A0 -  AF */
611 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  B0 -  BF */
612 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  C0 -  CF */
613 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  D0 -  DF */
614 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  E0 -  EF */
615 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  /*  F0 -  FF */
616 };
617 
618 
619 
620 void buffer_append_string_encoded(buffer *b, const char *s, size_t s_len, buffer_encoding_t encoding) {
621 	unsigned char *ds, *d;
622 	size_t d_len, ndx;
623 	const char *map = NULL;
624 
625 	force_assert(NULL != b);
626 	force_assert(NULL != s || 0 == s_len);
627 
628 	if (0 == s_len) return;
629 
630 	switch(encoding) {
631 	case ENCODING_REL_URI:
632 		map = encoded_chars_rel_uri;
633 		break;
634 	case ENCODING_REL_URI_PART:
635 		map = encoded_chars_rel_uri_part;
636 		break;
637 	case ENCODING_HTML:
638 		map = encoded_chars_html;
639 		break;
640 	case ENCODING_MINIMAL_XML:
641 		map = encoded_chars_minimal_xml;
642 		break;
643 	case ENCODING_HEX:
644 		map = encoded_chars_hex;
645 		break;
646 	case ENCODING_HTTP_HEADER:
647 		map = encoded_chars_http_header;
648 		break;
649 	}
650 
651 	force_assert(NULL != map);
652 
653 	/* count to-be-encoded-characters */
654 	for (ds = (unsigned char *)s, d_len = 0, ndx = 0; ndx < s_len; ds++, ndx++) {
655 		if (map[*ds]) {
656 			switch(encoding) {
657 			case ENCODING_REL_URI:
658 			case ENCODING_REL_URI_PART:
659 				d_len += 3;
660 				break;
661 			case ENCODING_HTML:
662 			case ENCODING_MINIMAL_XML:
663 				d_len += 6;
664 				break;
665 			case ENCODING_HTTP_HEADER:
666 			case ENCODING_HEX:
667 				d_len += 2;
668 				break;
669 			}
670 		} else {
671 			d_len++;
672 		}
673 	}
674 
675 	d = (unsigned char*) buffer_string_prepare_append(b, d_len);
676 	buffer_commit(b, d_len); /* fill below */
677 	force_assert('\0' == *d);
678 
679 	for (ds = (unsigned char *)s, d_len = 0, ndx = 0; ndx < s_len; ds++, ndx++) {
680 		if (map[*ds]) {
681 			switch(encoding) {
682 			case ENCODING_REL_URI:
683 			case ENCODING_REL_URI_PART:
684 				d[d_len++] = '%';
685 				d[d_len++] = hex_chars[((*ds) >> 4) & 0x0F];
686 				d[d_len++] = hex_chars[(*ds) & 0x0F];
687 				break;
688 			case ENCODING_HTML:
689 			case ENCODING_MINIMAL_XML:
690 				d[d_len++] = '&';
691 				d[d_len++] = '#';
692 				d[d_len++] = 'x';
693 				d[d_len++] = hex_chars[((*ds) >> 4) & 0x0F];
694 				d[d_len++] = hex_chars[(*ds) & 0x0F];
695 				d[d_len++] = ';';
696 				break;
697 			case ENCODING_HEX:
698 				d[d_len++] = hex_chars[((*ds) >> 4) & 0x0F];
699 				d[d_len++] = hex_chars[(*ds) & 0x0F];
700 				break;
701 			case ENCODING_HTTP_HEADER:
702 				d[d_len++] = *ds;
703 				d[d_len++] = '\t';
704 				break;
705 			}
706 		} else {
707 			d[d_len++] = *ds;
708 		}
709 	}
710 }
711 
712 void buffer_append_string_c_escaped(buffer *b, const char *s, size_t s_len) {
713 	unsigned char *ds, *d;
714 	size_t d_len, ndx;
715 
716 	force_assert(NULL != b);
717 	force_assert(NULL != s || 0 == s_len);
718 
719 	if (0 == s_len) return;
720 
721 	/* count to-be-encoded-characters */
722 	for (ds = (unsigned char *)s, d_len = 0, ndx = 0; ndx < s_len; ds++, ndx++) {
723 		if ((*ds < 0x20) /* control character */
724 				|| (*ds >= 0x7f)) { /* DEL + non-ASCII characters */
725 			switch (*ds) {
726 			case '\t':
727 			case '\r':
728 			case '\n':
729 				d_len += 2;
730 				break;
731 			default:
732 				d_len += 4; /* \xCC */
733 				break;
734 			}
735 		} else {
736 			d_len++;
737 		}
738 	}
739 
740 	d = (unsigned char*) buffer_string_prepare_append(b, d_len);
741 	buffer_commit(b, d_len); /* fill below */
742 	force_assert('\0' == *d);
743 
744 	for (ds = (unsigned char *)s, d_len = 0, ndx = 0; ndx < s_len; ds++, ndx++) {
745 		if ((*ds < 0x20) /* control character */
746 				|| (*ds >= 0x7f)) { /* DEL + non-ASCII characters */
747 			d[d_len++] = '\\';
748 			switch (*ds) {
749 			case '\t':
750 				d[d_len++] = 't';
751 				break;
752 			case '\r':
753 				d[d_len++] = 'r';
754 				break;
755 			case '\n':
756 				d[d_len++] = 'n';
757 				break;
758 			default:
759 				d[d_len++] = 'x';
760 				d[d_len++] = hex_chars[((*ds) >> 4) & 0x0F];
761 				d[d_len++] = hex_chars[(*ds) & 0x0F];
762 				break;
763 			}
764 		} else {
765 			d[d_len++] = *ds;
766 		}
767 	}
768 }
769 
770 
771 void buffer_copy_string_encoded_cgi_varnames(buffer *b, const char *s, size_t s_len, int is_http_header) {
772 	size_t i, j;
773 
774 	force_assert(NULL != b);
775 	force_assert(NULL != s || 0 == s_len);
776 
777 	buffer_reset(b);
778 
779 	if (is_http_header && NULL != s && 0 != strcasecmp(s, "CONTENT-TYPE")) {
780 		buffer_string_prepare_append(b, s_len + 5);
781 		buffer_copy_string_len(b, CONST_STR_LEN("HTTP_"));
782 	} else {
783 		buffer_string_prepare_append(b, s_len);
784 	}
785 
786 	j = buffer_string_length(b);
787 	for (i = 0; i < s_len; ++i) {
788 		unsigned char cr = s[i];
789 		if (light_isalpha(cr)) {
790 			/* upper-case */
791 			cr &= ~32;
792 		} else if (!light_isdigit(cr)) {
793 			cr = '_';
794 		}
795 		b->ptr[j++] = cr;
796 	}
797 	b->used = j;
798 	b->ptr[b->used++] = '\0';
799 }
800 
801 /* decodes url-special-chars inplace.
802  * replaces non-printable characters with '_'
803  */
804 
805 static void buffer_urldecode_internal(buffer *url, int is_query) {
806 	unsigned char high, low;
807 	char *src;
808 	char *dst;
809 
810 	force_assert(NULL != url);
811 	if (buffer_string_is_empty(url)) return;
812 
813 	force_assert('\0' == url->ptr[url->used-1]);
814 
815 	src = (char*) url->ptr;
816 
817 	while ('\0' != *src) {
818 		if ('%' == *src) break;
819 		if (is_query && '+' == *src) *src = ' ';
820 		src++;
821 	}
822 	dst = src;
823 
824 	while ('\0' != *src) {
825 		if (is_query && *src == '+') {
826 			*dst = ' ';
827 		} else if (*src == '%') {
828 			*dst = '%';
829 
830 			high = hex2int(*(src + 1));
831 			if (0xFF != high) {
832 				low = hex2int(*(src + 2));
833 				if (0xFF != low) {
834 					high = (high << 4) | low;
835 
836 					/* map control-characters out */
837 					if (high < 32 || high == 127) high = '_';
838 
839 					*dst = high;
840 					src += 2;
841 				}
842 			}
843 		} else {
844 			*dst = *src;
845 		}
846 
847 		dst++;
848 		src++;
849 	}
850 
851 	*dst = '\0';
852 	url->used = (dst - url->ptr) + 1;
853 }
854 
855 void buffer_urldecode_path(buffer *url) {
856 	buffer_urldecode_internal(url, 0);
857 }
858 
859 void buffer_urldecode_query(buffer *url) {
860 	buffer_urldecode_internal(url, 1);
861 }
862 
863 /* - special case: empty string returns empty string
864  * - on windows or cygwin: replace \ with /
865  * - strip leading spaces
866  * - prepends "/" if not present already
867  * - resolve "/../", "//" and "/./" the usual way:
868  *   the first one removes a preceding component, the other two
869  *   get compressed to "/".
870  * - "/." and "/.." at the end are similar, but always leave a trailing
871  *   "/"
872  *
873  * /blah/..         gets  /
874  * /blah/../foo     gets  /foo
875  * /abc/./xyz       gets  /abc/xyz
876  * /abc//xyz        gets  /abc/xyz
877  *
878  * NOTE: src and dest can point to the same buffer, in which case,
879  *       the operation is performed in-place.
880  */
881 
882 void buffer_path_simplify(buffer *dest, buffer *src)
883 {
884 	/* current character, the one before, and the one before that from input */
885 	char c, pre1, pre2;
886 	char *start, *slash, *walk, *out;
887 
888 	force_assert(NULL != dest && NULL != src);
889 
890 	if (buffer_string_is_empty(src)) {
891 		buffer_string_prepare_copy(dest, 0);
892 		return;
893 	}
894 
895 	force_assert('\0' == src->ptr[src->used-1]);
896 
897 	/* might need one character more for the '/' prefix */
898 	if (src == dest) {
899 		buffer_string_prepare_append(dest, 1);
900 	} else {
901 		buffer_string_prepare_copy(dest, buffer_string_length(src) + 1);
902 	}
903 
904 #if defined(__WIN32) || defined(__CYGWIN__)
905 	/* cygwin is treating \ and / the same, so we have to that too */
906 	{
907 		char *p;
908 		for (p = src->ptr; *p; p++) {
909 			if (*p == '\\') *p = '/';
910 		}
911 	}
912 #endif
913 
914 	walk  = src->ptr;
915 	start = dest->ptr;
916 	out   = dest->ptr;
917 	slash = dest->ptr;
918 
919 	/* skip leading spaces */
920 	while (*walk == ' ') {
921 		walk++;
922 	}
923 
924 	pre1 = 0;
925 	c = *(walk++);
926 	/* prefix with '/' if not already present */
927 	if (c != '/') {
928 		pre1 = '/';
929 		*(out++) = '/';
930 	}
931 
932 	while (c != '\0') {
933 		/* assert((src != dest || out <= walk) && slash <= out); */
934 		/* the following comments about out and walk are only interesting if
935 		 * src == dest; otherwise the memory areas don't overlap anyway.
936 		 */
937 		pre2 = pre1;
938 		pre1 = c;
939 
940 		/* possibly: out == walk - need to read first */
941 		c    = *walk;
942 		*out = pre1;
943 
944 		out++;
945 		walk++;
946 		/* (out <= walk) still true; also now (slash < out) */
947 
948 		if (c == '/' || c == '\0') {
949 			const size_t toklen = out - slash;
950 			if (toklen == 3 && pre2 == '.' && pre1 == '.') {
951 				/* "/../" or ("/.." at end of string) */
952 				out = slash;
953 				/* if there is something before "/..", there is at least one
954 				 * component, which needs to be removed */
955 				if (out > start) {
956 					out--;
957 					while (out > start && *out != '/') out--;
958 				}
959 
960 				/* don't kill trailing '/' at end of path */
961 				if (c == '\0') out++;
962 				/* slash < out before, so out_new <= slash + 1 <= out_before <= walk */
963 			} else if (toklen == 1 || (pre2 == '/' && pre1 == '.')) {
964 				/* "//" or "/./" or (("/" or "/.") at end of string) */
965 				out = slash;
966 				/* don't kill trailing '/' at end of path */
967 				if (c == '\0') out++;
968 				/* slash < out before, so out_new <= slash + 1 <= out_before <= walk */
969 			}
970 
971 			slash = out;
972 		}
973 	}
974 
975 	buffer_string_set_length(dest, out - start);
976 }
977 
978 int light_isdigit(int c) {
979 	return (c >= '0' && c <= '9');
980 }
981 
982 int light_isxdigit(int c) {
983 	if (light_isdigit(c)) return 1;
984 
985 	c |= 32;
986 	return (c >= 'a' && c <= 'f');
987 }
988 
989 int light_isalpha(int c) {
990 	c |= 32;
991 	return (c >= 'a' && c <= 'z');
992 }
993 
994 int light_isalnum(int c) {
995 	return light_isdigit(c) || light_isalpha(c);
996 }
997 
998 void buffer_to_lower(buffer *b) {
999 	size_t i;
1000 
1001 	for (i = 0; i < b->used; ++i) {
1002 		char c = b->ptr[i];
1003 		if (c >= 'A' && c <= 'Z') b->ptr[i] |= 0x20;
1004 	}
1005 }
1006 
1007 
1008 void buffer_to_upper(buffer *b) {
1009 	size_t i;
1010 
1011 	for (i = 0; i < b->used; ++i) {
1012 		char c = b->ptr[i];
1013 		if (c >= 'A' && c <= 'Z') b->ptr[i] &= ~0x20;
1014 	}
1015 }
1016 
1017 
1018 #include <stdio.h>
1019 
1020 #ifdef HAVE_LIBUNWIND
1021 # define UNW_LOCAL_ONLY
1022 # include <libunwind.h>
1023 
1024 static void print_backtrace(FILE *file) {
1025 	unw_cursor_t cursor;
1026 	unw_context_t context;
1027 	int ret;
1028 	unsigned int frame = 0;
1029 
1030 	if (0 != (ret = unw_getcontext(&context))) goto error;
1031 	if (0 != (ret = unw_init_local(&cursor, &context))) goto error;
1032 
1033 	fprintf(file, "Backtrace:\n");
1034 
1035 	while (0 < (ret = unw_step(&cursor))) {
1036 		unw_word_t proc_ip = 0;
1037 		unw_proc_info_t procinfo;
1038 		char procname[256];
1039 		unw_word_t proc_offset = 0;
1040 
1041 		if (0 != (ret = unw_get_reg(&cursor, UNW_REG_IP, &proc_ip))) goto error;
1042 
1043 		if (0 == proc_ip) {
1044 			/* without an IP the other functions are useless; unw_get_proc_name would return UNW_EUNSPEC */
1045 			++frame;
1046 			fprintf(file, "%u: (nil)\n", frame);
1047 			continue;
1048 		}
1049 
1050 		if (0 != (ret = unw_get_proc_info(&cursor, &procinfo))) goto error;
1051 
1052 		if (0 != (ret = unw_get_proc_name(&cursor, procname, sizeof(procname), &proc_offset))) {
1053 			switch (-ret) {
1054 			case UNW_ENOMEM:
1055 				memset(procname + sizeof(procname) - 4, '.', 3);
1056 				procname[sizeof(procname) - 1] = '\0';
1057 				break;
1058 			case UNW_ENOINFO:
1059 				procname[0] = '?';
1060 				procname[1] = '\0';
1061 				proc_offset = 0;
1062 				break;
1063 			default:
1064 				snprintf(procname, sizeof(procname), "?? (unw_get_proc_name error %d)", -ret);
1065 				break;
1066 			}
1067 		}
1068 
1069 		++frame;
1070 		fprintf(file, "%u: %s (+0x%x) [%p]\n",
1071 			frame,
1072 			procname,
1073 			(unsigned int) proc_offset,
1074 			(void*)(uintptr_t)proc_ip);
1075 	}
1076 
1077 	if (0 != ret) goto error;
1078 
1079 	return;
1080 
1081 error:
1082 	fprintf(file, "Error while generating backtrace: unwind error %i\n", (int) -ret);
1083 }
1084 #else
1085 static void print_backtrace(FILE *file) {
1086 	UNUSED(file);
1087 }
1088 #endif
1089 
1090 void log_failed_assert(const char *filename, unsigned int line, const char *msg) {
1091 	/* can't use buffer here; could lead to recursive assertions */
1092 	fprintf(stderr, "%s.%u: %s\n", filename, line, msg);
1093 	print_backtrace(stderr);
1094 	fflush(stderr);
1095 	abort();
1096 }
1097