xref: /lighttpd1.4/src/buffer.h (revision cfc8eeb5)
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); ptr
17  * might be NULL too then. otherwise an empty string has used == 1 (and ptr[0]
18  * == 0);
19  *
20  * copy/append functions will ensure used >= 1 (i.e. never leave it in the
21  * special empty state); only buffer_copy_buffer will copy the special empty
22  * state.
23  */
24 typedef struct {
25 	char *ptr;
26 
27 	/* "used" includes a terminating 0 */
28 	uint32_t used;
29 	/* size of allocated buffer at *ptr */
30 	uint32_t size;
31 } buffer;
32 
33 /* create new buffer; either empty or copy given data */
34 __attribute_returns_nonnull__
35 buffer* buffer_init(void);
36 
37 __attribute_returns_nonnull__
38 buffer* buffer_init_buffer(const buffer *src); /* src can  be NULL */
39 
40 __attribute_returns_nonnull__
41 buffer* buffer_init_string(const char *str); /* str can  be NULL */
42 
43 void buffer_free(buffer *b); /* b can be NULL */
44 
45 /* reset b. if NULL != b && NULL != src, move src content to b. reset src. */
46 __attribute_nonnull__
47 void buffer_move(buffer * restrict b, buffer * restrict src);
48 
49 /* make sure buffer is large enough to store a string of given size
50  * and a terminating zero.
51  * sets b to an empty string, and may drop old content.
52  * @return b->ptr
53  */
54 __attribute_nonnull__
55 __attribute_returns_nonnull__
56 char* buffer_string_prepare_copy(buffer *b, size_t size);
57 
58 /* allocate buffer large enough to be able to append a string of given size
59  * if b was empty (used == 0) it will contain an empty string (used == 1)
60  * afterwards
61  * "used" data is preserved; if not empty buffer must contain a
62  * zero terminated string.
63  */
64 __attribute_nonnull__
65 __attribute_returns_nonnull__
66 char* buffer_string_prepare_append(buffer *b, size_t size);
67 
68 /* extend and modify buffer for immediate addition of x bytes (differs from
69  * buffer_string_prepare_append() which only ensures space is available)
70  * returns pointer to which callers should immediately write x bytes
71  */
72 __attribute_nonnull__
73 __attribute_returns_nonnull__
74 char* buffer_extend(buffer * const restrict b, size_t x);
75 
76 /* use after prepare_(copy,append) when you have written data to the buffer
77  * to increase the buffer length by size. also sets the terminating zero.
78  * requires enough space is present for the terminating zero (prepare with the
79  * same size to be sure).
80  */
81 __attribute_nonnull__
82 void buffer_commit(buffer *b, size_t size);
83 
84 /* sets string length:
85  * - always stores a terminating zero to terminate the "new" string
86  * - does not modify the string data apart from terminating zero
87  * - reallocates the buffer iff needed
88  */
89 __attribute_nonnull__
90 void buffer_string_set_length(buffer *b, uint32_t len);
91 
92 /* clear buffer
93  * - invalidate buffer contents
94  * - unsets used chars but does not modify existing ptr contents
95  *   (b->ptr *is not* set to an empty, '\0'-terminated string "")
96  */
97 __attribute_nonnull__
98 static inline void buffer_clear(buffer *b);
99 
100 /* reset buffer
101  * - invalidate buffer contents
102  * - unsets used chars
103  * - keeps smaller buffer (unmodified) for reuse
104  *   (b->ptr *is not* set to an empty, '\0'-terminated string "")
105  * - frees larger buffer (b->size > BUFFER_MAX_REUSE_SIZE)
106  */
107 __attribute_nonnull__
108 static inline void buffer_reset(buffer *b);
109 
110 /* free buffer ptr
111  * - invalidate buffer contents; free ptr; reset ptr, used, size to 0
112  */
113 __attribute_cold__
114 __attribute_nonnull__
115 void buffer_free_ptr(buffer *b);
116 
117 void buffer_copy_string(buffer * restrict b, const char * restrict s);
118 void buffer_copy_string_len(buffer * restrict b, const char * restrict s, size_t len);
119 static inline void buffer_copy_buffer(buffer * restrict b, const buffer * restrict src);
120 
121 void buffer_append_string(buffer * restrict b, const char * restrict s);
122 void buffer_append_string_len(buffer * restrict b, const char * restrict s, size_t len);
123 void buffer_append_str2(buffer * restrict b, const char *s1, size_t len1, const char *s2, size_t len2);
124 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);
125 static inline void buffer_append_string_buffer(buffer * restrict b, const buffer * restrict src);
126 
127 struct const_iovec {
128   const void *iov_base;
129   size_t iov_len;
130 };
131 
132 __attribute_nonnull__
133 void buffer_append_iovec(buffer * restrict b, const struct const_iovec *iov, size_t n);
134 
135 #define buffer_append_uint_hex(b,len) buffer_append_uint_hex_lc((b),(len))
136 __attribute_nonnull__
137 void buffer_append_uint_hex_lc(buffer *b, uintmax_t len);
138 __attribute_nonnull__
139 void buffer_append_int(buffer *b, intmax_t val);
140 
141 void buffer_append_strftime(buffer * restrict b, const char * restrict format, const struct tm * restrict tm);
142 
143 /* '-', log_10 (2^bits) = bits * log 2 / log 10 < bits * 0.31, terminating 0 */
144 #define LI_ITOSTRING_LENGTH (2 + (8 * sizeof(intmax_t) * 31 + 99) / 100)
145 
146 __attribute_nonnull__
147 size_t li_itostrn(char *buf, size_t buf_len, intmax_t val);
148 __attribute_nonnull__
149 size_t li_utostrn(char *buf, size_t buf_len, uintmax_t val);
150 
151 /* buf must be (at least) 2*s_len + 1 big. uses lower-case hex letters. */
152 #define li_tohex(buf,buf_len,s,s_len) li_tohex_lc((buf),(buf_len),(s),(s_len))
153 __attribute_nonnull__
154 void li_tohex_lc(char * restrict buf, size_t buf_len, const char * restrict s, size_t s_len);
155 __attribute_nonnull__
156 void li_tohex_uc(char * restrict buf, size_t buf_len, const char * restrict s, size_t s_len);
157 
158 /* NULL buffer or empty buffer (used == 0);
159  * unset "string" (buffer) config options are initialized to used == 0,
160  * while setting an empty string leads to used == 1
161  */
162 __attribute_pure__
163 static inline int buffer_is_empty(const buffer *b);
164 /* NULL buffer, empty buffer (used == 0) or empty string (used == 1) */
165 __attribute_pure__
166 static inline int buffer_string_is_empty(const buffer *b);
167 
168 __attribute_nonnull__
169 __attribute_pure__
170 int buffer_eq_icase_ssn(const char * const a, const char * const b, const size_t len);
171 
172 __attribute_nonnull__
173 __attribute_pure__
174 int buffer_eq_icase_ss(const char * const a, const size_t alen, const char * const b, const size_t blen);
175 
176 __attribute_nonnull__
177 __attribute_pure__
178 int buffer_eq_icase_slen(const buffer * const b, const char * const s, const size_t slen);
179 #define buffer_is_equal_caseless_string buffer_eq_icase_slen
180 
181 __attribute_nonnull__
182 __attribute_pure__
183 int buffer_eq_slen(const buffer * const b, const char * const s, const size_t slen);
184 
185 __attribute_nonnull__
186 __attribute_pure__
187 int buffer_is_equal(const buffer *a, const buffer *b);
188 
189 __attribute_nonnull__
190 __attribute_pure__
191 int buffer_is_equal_right_len(const buffer *a, const buffer *b, size_t len);
192 
193 __attribute_nonnull__
194 __attribute_pure__
195 int buffer_is_equal_string(const buffer *a, const char *s, size_t b_len);
196 
197 __attribute_nonnull__
198 void buffer_substr_replace (buffer * restrict b, size_t offset, size_t len, const buffer * restrict replace);
199 
200 __attribute_nonnull__
201 void buffer_append_string_encoded_hex_lc(buffer * restrict b, const char * restrict s, size_t len);
202 __attribute_nonnull__
203 void buffer_append_string_encoded_hex_uc(buffer * restrict b, const char * restrict s, size_t len);
204 
205 typedef enum {
206 	ENCODING_REL_URI, /* for coding a rel-uri (/with space/and%percent) nicely as part of a href */
207 	ENCODING_REL_URI_PART, /* same as ENC_REL_URL plus coding / too as %2F */
208 	ENCODING_HTML,         /* & becomes &amp; and so on */
209 	ENCODING_MINIMAL_XML   /* minimal encoding for xml */
210 } buffer_encoding_t;
211 
212 void buffer_append_string_encoded(buffer * restrict b, const char * restrict s, size_t s_len, buffer_encoding_t encoding);
213 
214 /* escape non-printable characters; simple escapes for \t, \r, \n; fallback to \xCC */
215 __attribute_nonnull__
216 void buffer_append_string_c_escaped(buffer * restrict b, const char * restrict s, size_t s_len);
217 
218 __attribute_nonnull__
219 void buffer_urldecode_path(buffer *b);
220 
221 __attribute_nonnull__
222 __attribute_pure__
223 int buffer_is_valid_UTF8(const buffer *b);
224 
225 __attribute_nonnull__
226 void buffer_path_simplify(buffer *dest, buffer *src);
227 
228 __attribute_nonnull__
229 void buffer_to_lower(buffer *b);
230 __attribute_nonnull__
231 void buffer_to_upper(buffer *b);
232 
233 
234 /** deprecated */
235 __attribute_const__
236 char hex2int(unsigned char c);
237 
238 __attribute_pure__
239 static inline int light_isdigit(int c);
240 static inline int light_isdigit(int c) {
241 	return ((uint32_t)c-'0' <= '9'-'0');
242 }
243 
244 __attribute_pure__
245 static inline int light_isxdigit(int c);
246 static inline int light_isxdigit(int c) {
247 	return light_isdigit(c) || (((uint32_t)c | 0x20)-'a' <= 'f'-'a');
248 }
249 
250 __attribute_pure__
251 static inline int light_isalpha(int c);
252 static inline int light_isalpha(int c) {
253 	return (((uint32_t)c | 0x20)-'a' <= 'z'-'a');
254 }
255 
256 __attribute_pure__
257 static inline int light_isalnum(int c);
258 static inline int light_isalnum(int c) {
259 	return light_isdigit(c) || light_isalpha(c);
260 }
261 
262 #define light_isupper(c) ((uint32_t)(c)-'A' <= 'Z'-'A')
263 #define light_islower(c) ((uint32_t)(c)-'a' <= 'z'-'a')
264 
265 #define light_bshift(b)           ((uint64_t)1uL << (b))
266 #define light_btst(a,b)  ((a) &   ((uint64_t)1uL << (b)))
267 #define light_bclr(a,b)  ((a) &= ~((uint64_t)1uL << (b)))
268 #define light_bset(a,b)  ((a) |=  ((uint64_t)1uL << (b)))
269 
270 
271 __attribute_pure__
272 static inline uint32_t buffer_string_length(const buffer *b); /* buffer string length without terminating 0 */
273 
274 __attribute_nonnull__
275 __attribute_pure__
276 static inline uint32_t buffer_string_space(const buffer *b); /* maximum length of string that can be stored without reallocating */
277 
278 __attribute_nonnull__
279 static inline void buffer_append_slash(buffer *b); /* append '/' no non-empty strings not ending in '/' */
280 
281 void buffer_append_path_len(buffer * restrict b, const char * restrict a, size_t alen); /* join strings with '/', if '/' not present */
282 
283 __attribute_nonnull__
284 __attribute_pure__
285 static inline int buffer_has_slash_suffix (const buffer * const b);
286 
287 __attribute_nonnull__
288 __attribute_pure__
289 static inline int buffer_has_pathsep_suffix (const buffer * const b);
290 
291 #define BUFFER_APPEND_STRING_CONST(x, y) \
292 	buffer_append_string_len(x, y, sizeof(y) - 1)
293 
294 #define BUFFER_COPY_STRING_CONST(x, y) \
295 	buffer_copy_string_len(x, y, sizeof(y) - 1)
296 
297 #define BUFFER_INTLEN_PTR(x) (x)->used ? (int)((x)->used - 1) : 0, (x)->ptr
298 
299 #define CONST_LEN_STR(x) (uint32_t)sizeof(x)-1, x
300 #define CONST_STR_LEN(x) x, (uint32_t)sizeof(x) - 1
301 #define CONST_BUF_LEN(x) ((x) ? (x)->ptr : NULL), buffer_string_length(x)
302 
303 
304 #define LI_NORETURN __attribute_noreturn__
305 
306 __attribute_cold__
307 void log_failed_assert(const char *filename, unsigned int line, const char *msg) LI_NORETURN;
308 #define force_assert(x) do { if (!(x)) log_failed_assert(__FILE__, __LINE__, "assertion failed: " #x); } while(0)
309 #define SEGFAULT() log_failed_assert(__FILE__, __LINE__, "aborted");
310 
311 /* inline implementations */
312 
313 static inline int buffer_is_empty(const buffer *b) {
314 	return NULL == b || 0 == b->used;
315 }
316 static inline int buffer_string_is_empty(const buffer *b) {
317 	return NULL == b || b->used < 2;
318 }
319 
320 static inline uint32_t buffer_string_length(const buffer *b) {
321 	return NULL != b && 0 != b->used ? b->used - 1 : 0;
322 }
323 
324 static inline uint32_t buffer_string_space(const buffer *b) {
325 	return b->size ? b->size - (b->used | (0 == b->used)) : 0;
326 }
327 
328 static inline void buffer_copy_buffer(buffer * restrict b, const buffer * restrict src) {
329 	buffer_copy_string_len(b, CONST_BUF_LEN(src));
330 }
331 
332 static inline void buffer_append_string_buffer(buffer * restrict b, const buffer * restrict src) {
333 	buffer_append_string_len(b, CONST_BUF_LEN(src));
334 }
335 
336 static inline void buffer_append_slash(buffer *b) {
337 	uint32_t len = buffer_string_length(b);
338 	if (len > 0 && '/' != b->ptr[len-1]) BUFFER_APPEND_STRING_CONST(b, "/");
339 }
340 
341 static inline void buffer_clear(buffer *b) {
342 	b->used = 0;
343 }
344 
345 static inline void buffer_reset(buffer *b) {
346 	b->used = 0;
347 	/* release buffer larger than BUFFER_MAX_REUSE_SIZE bytes */
348 	if (b->size > BUFFER_MAX_REUSE_SIZE) buffer_free_ptr(b);
349 }
350 
351 static inline int buffer_has_slash_suffix (const buffer * const b) {
352     return (b->used > 1 && b->ptr[b->used-2] == '/');
353 }
354 
355 static inline int buffer_has_pathsep_suffix (const buffer * const b) {
356     return (b->used > 1 && b->ptr[b->used-2] == '/');
357 }
358 
359 #endif
360