xref: /lighttpd1.4/src/buffer.h (revision af3df29a)
1 #ifndef _BUFFER_H_
2 #define _BUFFER_H_
3 #include "first.h"
4 
5 struct tm;              /* declaration */
6 
7 /**
8  * max size of a buffer which will just be reset
9  * to ->used = 0 instead of really freeing the buffer
10  */
11 #define BUFFER_MAX_REUSE_SIZE 4096
12 
13 /* generic string + binary data container; contains a terminating 0 in both
14  * cases
15  *
16  * used == 0 indicates a special "empty" state (unset config values);
17  * ptr might be NULL, too.
18  *
19  * copy/append functions will ensure used >= 1
20  * (i.e. never leave it in the special empty state)
21  */
22 typedef struct {
23 	char *ptr;
24 
25 	/* "used" includes a terminating 0 */
26 	uint32_t used;
27 	/* size of allocated buffer at *ptr */
28 	uint32_t size;
29 } buffer;
30 
31 /* create new buffer; either empty or copy given data */
32 __attribute_returns_nonnull__
33 buffer* buffer_init(void);
34 
35 __attribute_nonnull__
36 __attribute_returns_nonnull__
37 buffer* buffer_init_buffer(const buffer *src);
38 
39 __attribute_returns_nonnull__
40 buffer* buffer_init_string(const char *str); /* str can  be NULL */
41 
42 void buffer_free(buffer *b); /* b can be NULL */
43 
44 /* reset b. if NULL != b && NULL != src, move src content to b. reset src. */
45 __attribute_nonnull__
46 void buffer_move(buffer * restrict b, buffer * restrict src);
47 
48 /* make sure buffer is large enough to store a string of given size
49  * and a terminating zero.
50  * sets b to an empty string, and may drop old content.
51  * @return b->ptr
52  */
53 __attribute_nonnull__
54 __attribute_returns_nonnull__
55 char* buffer_string_prepare_copy(buffer *b, size_t size);
56 
57 /* allocate buffer large enough to be able to append a string of given size
58  * if b was empty (used == 0) it will contain an empty string (used == 1)
59  * afterwards
60  * "used" data is preserved; if not empty buffer must contain a
61  * zero terminated string.
62  */
63 __attribute_nonnull__
64 __attribute_returns_nonnull__
65 char* buffer_string_prepare_append(buffer *b, size_t size);
66 
67 /* extend and modify buffer for immediate addition of x bytes (differs from
68  * buffer_string_prepare_append() which only ensures space is available)
69  * returns pointer to which callers should immediately write x bytes
70  */
71 __attribute_nonnull__
72 __attribute_returns_nonnull__
73 char* buffer_extend(buffer * const restrict b, size_t x);
74 
75 /* use after prepare_(copy,append) when you have written data to the buffer
76  * to increase the buffer length by size. also sets the terminating zero.
77  * requires enough space is present for the terminating zero (prepare with the
78  * same size to be sure).
79  */
80 __attribute_nonnull__
81 void buffer_commit(buffer *b, size_t size);
82 
83 /* clear buffer
84  * - invalidate buffer contents
85  * - unsets used chars but does not modify existing ptr contents
86  *   (b->ptr *is not* set to an empty, '\0'-terminated string "")
87  */
88 __attribute_nonnull__
89 static inline void buffer_clear(buffer *b);
90 
91 /* reset buffer
92  * - invalidate buffer contents
93  * - unsets used chars
94  * - keeps smaller buffer (unmodified) for reuse
95  *   (b->ptr *is not* set to an empty, '\0'-terminated string "")
96  * - frees larger buffer (b->size > BUFFER_MAX_REUSE_SIZE)
97  */
98 __attribute_nonnull__
99 static inline void buffer_reset(buffer *b);
100 
101 /* free buffer ptr
102  * - invalidate buffer contents; free ptr; reset ptr, used, size to 0
103  */
104 __attribute_cold__
105 __attribute_nonnull__
106 void buffer_free_ptr(buffer *b);
107 
108 void buffer_copy_string(buffer * restrict b, const char * restrict s);
109 void buffer_copy_string_len(buffer * restrict b, const char * restrict s, size_t len);
110 
111 void buffer_append_string(buffer * restrict b, const char * restrict s);
112 void buffer_append_string_len(buffer * restrict b, const char * restrict s, size_t len);
113 void buffer_append_str2(buffer * restrict b, const char *s1, size_t len1, const char *s2, size_t len2);
114 void buffer_append_str3(buffer * restrict b, const char *s1, size_t len1, const char *s2, size_t len2, const char *s3, size_t len3);
115 
116 struct const_iovec {
117   const void *iov_base;
118   size_t iov_len;
119 };
120 
121 __attribute_nonnull__
122 void buffer_append_iovec(buffer * restrict b, const struct const_iovec *iov, size_t n);
123 
124 #define buffer_append_uint_hex(b,len) buffer_append_uint_hex_lc((b),(len))
125 __attribute_nonnull__
126 void buffer_append_uint_hex_lc(buffer *b, uintmax_t len);
127 __attribute_nonnull__
128 void buffer_append_int(buffer *b, intmax_t val);
129 
130 void buffer_append_strftime(buffer * restrict b, const char * restrict format, const struct tm * restrict tm);
131 
132 /* '-', log_10 (2^bits) = bits * log 2 / log 10 < bits * 0.31, terminating 0 */
133 #define LI_ITOSTRING_LENGTH (2 + (8 * sizeof(intmax_t) * 31 + 99) / 100)
134 
135 __attribute_nonnull__
136 size_t li_itostrn(char *buf, size_t buf_len, intmax_t val);
137 __attribute_nonnull__
138 size_t li_utostrn(char *buf, size_t buf_len, uintmax_t val);
139 
140 /* buf must be (at least) 2*s_len + 1 big. uses lower-case hex letters. */
141 #define li_tohex(buf,buf_len,s,s_len) li_tohex_lc((buf),(buf_len),(s),(s_len))
142 __attribute_nonnull__
143 void li_tohex_lc(char * restrict buf, size_t buf_len, const char * restrict s, size_t s_len);
144 __attribute_nonnull__
145 void li_tohex_uc(char * restrict buf, size_t buf_len, const char * restrict s, size_t s_len);
146 
147 __attribute_nonnull__
148 __attribute_pure__
149 int buffer_eq_icase_ssn(const char * const a, const char * const b, const size_t len);
150 
151 __attribute_nonnull__
152 __attribute_pure__
153 int buffer_eq_icase_ss(const char * const a, const size_t alen, const char * const b, const size_t blen);
154 
155 __attribute_nonnull__
156 __attribute_pure__
157 int buffer_eq_icase_slen(const buffer * const b, const char * const s, const size_t slen);
158 
159 __attribute_nonnull__
160 __attribute_pure__
161 int buffer_eq_slen(const buffer * const b, const char * const s, const size_t slen);
162 
163 __attribute_nonnull__
164 __attribute_pure__
165 int buffer_is_equal(const buffer *a, const buffer *b);
166 
167 __attribute_nonnull__
168 void buffer_substr_replace (buffer * restrict b, size_t offset, size_t len, const buffer * restrict replace);
169 
170 __attribute_nonnull__
171 void buffer_append_string_encoded_hex_lc(buffer * restrict b, const char * restrict s, size_t len);
172 __attribute_nonnull__
173 void buffer_append_string_encoded_hex_uc(buffer * restrict b, const char * restrict s, size_t len);
174 
175 typedef enum {
176 	ENCODING_REL_URI, /* for coding a rel-uri (/with space/and%percent) nicely as part of a href */
177 	ENCODING_REL_URI_PART, /* same as ENC_REL_URL plus coding / too as %2F */
178 	ENCODING_HTML,         /* & becomes &amp; and so on */
179 	ENCODING_MINIMAL_XML   /* minimal encoding for xml */
180 } buffer_encoding_t;
181 
182 void buffer_append_string_encoded(buffer * restrict b, const char * restrict s, size_t s_len, buffer_encoding_t encoding);
183 
184 /* escape non-printable characters; simple escapes for \t, \r, \n; fallback to \xCC */
185 __attribute_nonnull__
186 void buffer_append_string_c_escaped(buffer * restrict b, const char * restrict s, size_t s_len);
187 
188 __attribute_nonnull__
189 void buffer_urldecode_path(buffer *b);
190 
191 __attribute_nonnull__
192 __attribute_pure__
193 int buffer_is_valid_UTF8(const buffer *b);
194 
195 __attribute_nonnull__
196 void buffer_path_simplify(buffer *b);
197 
198 __attribute_nonnull__
199 void buffer_to_lower(buffer *b);
200 __attribute_nonnull__
201 void buffer_to_upper(buffer *b);
202 
203 
204 /** deprecated */
205 __attribute_const__
206 char hex2int(unsigned char c);
207 
208 int li_hex2bin (unsigned char *bin, size_t binlen, const char *hexstr, size_t len);
209 
210 __attribute_pure__
211 static inline int light_isdigit(int c);
212 static inline int light_isdigit(int c) {
213 	return ((uint32_t)c-'0' <= '9'-'0');
214 }
215 
216 __attribute_pure__
217 static inline int light_isxdigit(int c);
218 static inline int light_isxdigit(int c) {
219 	return light_isdigit(c) || (((uint32_t)c | 0x20)-'a' <= 'f'-'a');
220 }
221 
222 __attribute_pure__
223 static inline int light_isalpha(int c);
224 static inline int light_isalpha(int c) {
225 	return (((uint32_t)c | 0x20)-'a' <= 'z'-'a');
226 }
227 
228 __attribute_pure__
229 static inline int light_isalnum(int c);
230 static inline int light_isalnum(int c) {
231 	return light_isdigit(c) || light_isalpha(c);
232 }
233 
234 #define light_isupper(c) ((uint32_t)(c)-'A' <= 'Z'-'A')
235 #define light_islower(c) ((uint32_t)(c)-'a' <= 'z'-'a')
236 
237 #define light_bshift(b)           ((uint64_t)1uL << (b))
238 #define light_btst(a,b)  ((a) &   ((uint64_t)1uL << (b)))
239 #define light_bclr(a,b)  ((a) &= ~((uint64_t)1uL << (b)))
240 #define light_bset(a,b)  ((a) |=  ((uint64_t)1uL << (b)))
241 
242 
243 void buffer_append_path_len(buffer * restrict b, const char * restrict a, size_t alen); /* join strings with '/', if '/' not present */
244 void buffer_copy_path_len2(buffer * restrict b, const char * restrict s1, size_t len1, const char * restrict s2, size_t len2);
245 
246 __attribute_nonnull__
247 __attribute_pure__
248 static inline int buffer_has_slash_suffix (const buffer * const b);
249 
250 __attribute_nonnull__
251 __attribute_pure__
252 static inline int buffer_has_pathsep_suffix (const buffer * const b);
253 
254 #define BUFFER_INTLEN_PTR(x) (int)buffer_clen(x), (x)->ptr
255 #define BUF_PTR_LEN(x)       (x)->ptr, buffer_clen(x)
256 
257 #define CONST_LEN_STR(x) (uint32_t)sizeof(x)-1, x
258 #define CONST_STR_LEN(x) x, (uint32_t)sizeof(x) - 1
259 
260 
261 #define LI_NORETURN __attribute_noreturn__
262 
263 __attribute_cold__
264 void log_failed_assert(const char *filename, unsigned int line, const char *msg) LI_NORETURN;
265 #define force_assert(x) do { if (!(x)) log_failed_assert(__FILE__, __LINE__, "assertion failed: " #x); } while(0)
266 #define SEGFAULT() log_failed_assert(__FILE__, __LINE__, "aborted");
267 
268 
269 /* inline implementations */
270 
271 __attribute_nonnull__
272 __attribute_pure__
273 static inline int buffer_is_unset(const buffer *b);
274 static inline int buffer_is_unset(const buffer *b) {
275     return 0 == b->used;
276 }
277 
278 __attribute_nonnull__
279 __attribute_pure__
280 static inline int buffer_is_blank(const buffer *b);
281 static inline int buffer_is_blank(const buffer *b) {
282     return b->used < 2; /* buffer_is_blank() || buffer_is_unset() */
283 }
284 
285 /* buffer "C" len (bytes) */
286 __attribute_nonnull__
287 __attribute_pure__
288 static inline uint32_t buffer_clen (const buffer *b);
289 static inline uint32_t buffer_clen (const buffer *b) {
290     return b->used - (0 != b->used);
291 }
292 
293 /* buffer space remaining to append string without reallocating */
294 __attribute_nonnull__
295 __attribute_pure__
296 static inline uint32_t buffer_string_space(const buffer *b);
297 static inline uint32_t buffer_string_space(const buffer *b) {
298     return b->size ? b->size - (b->used | (0 == b->used)) : 0;
299 }
300 
301 __attribute_nonnull__
302 static inline void buffer_copy_buffer(buffer * restrict b, const buffer * restrict src);
303 static inline void buffer_copy_buffer(buffer * restrict b, const buffer * restrict src) {
304     buffer_copy_string_len(b, BUF_PTR_LEN(src));
305 }
306 
307 __attribute_nonnull__
308 static inline void buffer_append_buffer(buffer * restrict b, const buffer * restrict src);
309 static inline void buffer_append_buffer(buffer * restrict b, const buffer * restrict src) {
310     buffer_append_string_len(b, BUF_PTR_LEN(src));
311 }
312 
313 __attribute_nonnull__
314 static inline void buffer_truncate(buffer *b, uint32_t len);
315 static inline void buffer_truncate(buffer *b, uint32_t len) {
316     b->ptr[len] = '\0'; /* b->ptr must exist; use buffer_blank() for trunc 0 */
317     b->used = len + 1;
318 }
319 
320 __attribute_nonnull__
321 static inline void buffer_blank(buffer *b);
322 static inline void buffer_blank(buffer *b) {
323     b->ptr ? buffer_truncate(b, 0) : (void)buffer_extend(b, 0);
324 }
325 
326 /* append '/' to non-empty strings not ending in '/' */
327 __attribute_nonnull__
328 static inline void buffer_append_slash(buffer *b);
329 static inline void buffer_append_slash(buffer *b) {
330     const uint32_t len = buffer_clen(b);
331     if (len > 0 && '/' != b->ptr[len-1])
332         buffer_append_string_len(b, CONST_STR_LEN("/"));
333 }
334 
335 static inline void buffer_clear(buffer *b) {
336 	b->used = 0;
337 }
338 
339 static inline void buffer_reset(buffer *b) {
340 	b->used = 0;
341 	/* release buffer larger than BUFFER_MAX_REUSE_SIZE bytes */
342 	if (b->size > BUFFER_MAX_REUSE_SIZE) buffer_free_ptr(b);
343 }
344 
345 static inline int buffer_has_slash_suffix (const buffer * const b) {
346     return (b->used > 1 && b->ptr[b->used-2] == '/');
347 }
348 
349 static inline int buffer_has_pathsep_suffix (const buffer * const b) {
350     return (b->used > 1 && b->ptr[b->used-2] == '/');
351 }
352 
353 
354 /* backwards compat (deprecated; older interfaces) */
355 
356 #define buffer_append_string_buffer buffer_append_buffer
357 #define buffer_is_equal_caseless_string buffer_eq_icase_slen
358 #define buffer_is_equal_string buffer_eq_slen
359 
360 #define BUFFER_APPEND_STRING_CONST(x, y) \
361 	buffer_append_string_len(x, y, sizeof(y) - 1)
362 
363 #define BUFFER_COPY_STRING_CONST(x, y) \
364 	buffer_copy_string_len(x, y, sizeof(y) - 1)
365 
366 #define CONST_BUF_LEN(x) ((x) ? (x)->ptr : NULL), buffer_string_length(x)
367 
368 /* NULL buffer or empty buffer (used == 0);
369  * unset "string" (buffer) config options are initialized to used == 0,
370  * while setting an empty string leads to used == 1
371  */
372 __attribute_pure__
373 static inline int buffer_is_empty(const buffer *b);
374 static inline int buffer_is_empty(const buffer *b) {
375 	return NULL == b || buffer_is_unset(b);
376 }
377 /* NULL buffer, empty buffer (used == 0) or empty string (used == 1) */
378 __attribute_pure__
379 static inline int buffer_string_is_empty(const buffer *b);
380 static inline int buffer_string_is_empty(const buffer *b) {
381 	return NULL == b || buffer_is_blank(b);
382 }
383 
384 /* buffer string length without terminating 0 */
385 __attribute_pure__
386 static inline uint32_t buffer_string_length(const buffer *b);
387 static inline uint32_t buffer_string_length(const buffer *b) {
388 	return NULL != b ? buffer_clen(b) : 0;
389 }
390 
391 /* sets string length:
392  * - deprecated; use buffer_truncate() or buffer_extend() instead
393  * - always stores a terminating zero to terminate the "new" string
394  * - does not modify the string data apart from terminating zero
395  * - reallocates the buffer iff needed
396  */
397 __attribute_nonnull__
398 static inline void buffer_string_set_length(buffer *b, uint32_t len);
399 static inline void buffer_string_set_length(buffer *b, uint32_t len) {
400     if (len < b->size)
401         buffer_truncate(b, len);
402     else
403         buffer_extend(b, len - buffer_clen(b));
404 }
405 
406 
407 #endif
408