1 /* Licensed under LGPLv2+ - see LICENSE file for details */
2 #ifndef CCAN_BYTESTRING_H_
3 #define CCAN_BYTESTRING_H_
12 #include <ccan/array_size/array_size.h>
13 #include <ccan/mem/mem.h>
14 #include <ccan/compiler/compiler.h>
22 * bytestring - construct a new bytestring
23 * @p: pointer to the content of the bytestring
24 * @l: length of the bytestring
26 * Builds a new bytestring starting at p, of length l.
29 * char x[5] = "abcde";
30 * struct bytestring bs = bytestring(x, 5);
31 * assert(bs.len == 5);
33 static inline CONST_FUNCTION struct bytestring
34 bytestring(const char *p, size_t l)
36 struct bytestring bs = {
44 #define bytestring_NULL bytestring(NULL, 0)
47 * BYTESTRING - construct a bytestring from a string literal
50 * Builds a new bytestring containing the given literal string, not
51 * including the terminating \0 (but including any internal \0s).
54 * assert(BYTESTRING("abc\0def").len == 7);
56 #define BYTESTRING(s) (bytestring((s), ARRAY_SIZE(s) - 1))
59 * BYTESTRING_INIT - bytestring initializer
62 * Produces an initializer for a bytestring from a literal string.
63 * The resulting bytestring will not include the terminating \0, but
64 * will include any internal \0s.
67 * static const struct bytestring CONSTANT = BYTESTRING_INIT("CONSTANT");
69 #define BYTESTRING_INIT(s) { .ptr = (s), .len = ARRAY_SIZE(s) - 1}
72 * bytestring_from_string - construct a bytestring from a NUL terminated string
73 * @s: NUL-terminated string pointer
75 * Builds a new bytestring containing the given NUL-terminated string,
76 * up to, but not including, the terminating \0.
79 * assert(bytestring_from_string("abc\0def").len == 3);
81 static inline struct bytestring bytestring_from_string(const char *s)
84 return bytestring_NULL;
85 return bytestring(s, strlen(s));
89 * bytestring_eq - test if bytestrings have identical content
92 * Returns 1 if the given bytestrings have identical length and
93 * content, 0 otherwise.
95 static inline bool bytestring_eq(struct bytestring a, struct bytestring b)
97 return (a.len == b.len)
98 && (memcmp(a.ptr, b.ptr, a.len) == 0);
102 * bytestring_byte - get a byte from a bytestring
106 * Return the @n-th byte from @s. Aborts (via assert) if @n is out of
107 * range for the length of @s.
109 static inline char bytestring_byte(struct bytestring s, size_t n)
116 * bytestring_slice - extract a substring from a bytestring
118 * @start, @end: indexes
120 * Return a sub-bytestring of @s, starting at byte index @start, and
121 * running to, but not including byte @end. If @end is before start,
122 * returns a zero-length bytestring. If @start is out of range,
123 * return a zero length bytestring at the end of @s.
125 * Note that this doesn't copy or allocate anything - the returned
126 * bytestring occupies (some of) the same memory as the given
129 static inline struct bytestring bytestring_slice(struct bytestring s,
130 size_t start, size_t end)
139 return bytestring(s.ptr + start, end - start);
143 * bytestring_starts - test if the start of one bytestring matches another
144 * @s, @prefix: bytestrings
146 * Returns true if @prefix appears as a substring at the beginning of
147 * @s, false otherwise.
149 static inline bool bytestring_starts(struct bytestring s,
150 struct bytestring prefix)
152 return (s.len >= prefix.len) && (memcmp(s.ptr,
153 prefix.ptr, prefix.len) == 0);
157 * bytestring_ends - test if the end of one bytestring matches another
158 * @s, @suffix: bytestrings
160 * Returns true if @suffix appears as a substring at the end of @s,
163 static inline bool bytestring_ends(struct bytestring s,
164 struct bytestring suffix)
166 return (s.len >= suffix.len) && (memcmp(s.ptr + s.len - suffix.len,
167 suffix.ptr, suffix.len) == 0);
171 * bytestring_index - locate character in bytestring
172 * @haystack: a bytestring
173 * @needle: a character or byte value
175 * Returns a pointer to the first occurrence of @needle within
176 * @haystack, or NULL if @needle does not appear in @haystack.
178 static inline const char *bytestring_index(struct bytestring haystack,
181 return memchr(haystack.ptr, needle, haystack.len);
185 * bytestring_rindex - locate character in bytestring
186 * @haystack: a bytestring
187 * @needle: a character or byte value
189 * Returns a pointer to the last occurrence of @needle within
190 * @haystack, or NULL if @needle does not appear in @haystack.
192 static inline const char *bytestring_rindex(struct bytestring haystack,
195 return memrchr(haystack.ptr, needle, haystack.len);
199 * bytestring_bytestring - search for a bytestring in another bytestring
200 * @haystack, @needle: bytestrings
202 * Returns a bytestring corresponding to the first occurrence of
203 * @needle in @haystack, or bytestring_NULL if @needle is not found
206 static inline struct bytestring bytestring_bytestring(struct bytestring haystack,
207 struct bytestring needle)
209 const char *p = memmem(haystack.ptr, haystack.len,
210 needle.ptr, needle.len);
212 return bytestring(p, needle.len);
214 return bytestring_NULL;
218 * bytestring_spn - search a bytestring for a set of bytes
220 * @accept: a bytestring containing a set of bytes to accept
222 * Returns the length, in bytes, of the initial segment of @s which
223 * consists entirely of characters in @accept.
225 size_t bytestring_spn(struct bytestring s, struct bytestring accept);
228 * bytestring_cspn - search a bytestring for a set of bytes (complemented)
230 * @reject: a bytestring containing a set of bytes to reject
232 * Returns the length, in bytes, of the initial segment of @s which
233 * consists entirely of characters not in @reject.
235 size_t bytestring_cspn(struct bytestring s, struct bytestring reject);
238 * bytestring_splitchr_first - split a bytestring on a single character delimiter
239 * @whole: a bytestring
240 * @delim: delimiter character
242 * Returns the first @delim delimited substring of @whole.
244 struct bytestring bytestring_splitchr_first(struct bytestring whole,
248 * bytestring_splitchr_next - split a bytestring on a single character delimiter
249 * @whole: a bytestring
250 * @delim: delimiter character
251 * @prev: last substring
253 * Returns the next @delim delimited substring of @whole after @prev.
255 struct bytestring bytestring_splitchr_next(struct bytestring whole,
256 char delim, struct bytestring prev);
258 #define bytestring_foreach_splitchr(_s, _w, _delim) \
259 for ((_s) = bytestring_splitchr_first((_w), (_delim)); \
261 (_s) = bytestring_splitchr_next((_w), (_delim), (_s)))
264 * bytestring_splitchrs_first - split a bytestring on a set of delimiter
266 * @whole: a bytestring
267 * @delim: delimiter characters
269 * Returns the first substring of @whole delimited by any character in
272 struct bytestring bytestring_splitchrs_first(struct bytestring whole,
273 struct bytestring delim);
276 * bytestring_splitchr_next - split a bytestring on a set of delimiter
278 * @whole: a bytestring
279 * @delim: delimiter character
280 * @prev: last substring
282 * Returns the next @delim delimited substring of @whole after @prev.
284 struct bytestring bytestring_splitchrs_next(struct bytestring whole,
285 struct bytestring delim,
286 struct bytestring prev);
288 #define bytestring_foreach_splitchrs(_s, _w, _delim) \
289 for ((_s) = bytestring_splitchrs_first((_w), (_delim)); \
291 (_s) = bytestring_splitchrs_next((_w), (_delim), (_s)))
294 * bytestring_splitstr_first - split a bytestring on a delimiter string
295 * @whole: a bytestring
296 * @delim: delimiter substring
298 * Returns the first substring of @whole delimited by the substring in
301 struct bytestring bytestring_splitstr_first(struct bytestring whole,
302 struct bytestring delim);
305 * bytestring_splitstr_next - split a bytestring on a delimiter string
306 * @whole: a bytestring
307 * @delim: delimiter string
308 * @prev: last substring
310 * Returns the next @delim delimited substring of @whole after @prev.
312 struct bytestring bytestring_splitstr_next(struct bytestring whole,
313 struct bytestring delim,
314 struct bytestring prev);
316 #define bytestring_foreach_splitstr(_s, _w, _delim) \
317 for ((_s) = bytestring_splitstr_first((_w), (_delim)); \
319 (_s) = bytestring_splitstr_next((_w), (_delim), (_s)))
321 #endif /* CCAN_BYTESTRING_H_ */