Merge branch 'jk/strbuf-detach-always-non-null'
[git/git.git] / strbuf.c
1 #include "cache.h"
2 #include "refs.h"
3
4 int prefixcmp(const char *str, const char *prefix)
5 {
6 for (; ; str++, prefix++)
7 if (!*prefix)
8 return 0;
9 else if (*str != *prefix)
10 return (unsigned char)*prefix - (unsigned char)*str;
11 }
12
13 int suffixcmp(const char *str, const char *suffix)
14 {
15 int len = strlen(str), suflen = strlen(suffix);
16 if (len < suflen)
17 return -1;
18 else
19 return strcmp(str + len - suflen, suffix);
20 }
21
22 /*
23 * Used as the default ->buf value, so that people can always assume
24 * buf is non NULL and ->buf is NUL terminated even for a freshly
25 * initialized strbuf.
26 */
27 char strbuf_slopbuf[1];
28
29 void strbuf_init(struct strbuf *sb, size_t hint)
30 {
31 sb->alloc = sb->len = 0;
32 sb->buf = strbuf_slopbuf;
33 if (hint)
34 strbuf_grow(sb, hint);
35 }
36
37 void strbuf_release(struct strbuf *sb)
38 {
39 if (sb->alloc) {
40 free(sb->buf);
41 strbuf_init(sb, 0);
42 }
43 }
44
45 char *strbuf_detach(struct strbuf *sb, size_t *sz)
46 {
47 char *res;
48 strbuf_grow(sb, 0);
49 res = sb->buf;
50 if (sz)
51 *sz = sb->len;
52 strbuf_init(sb, 0);
53 return res;
54 }
55
56 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
57 {
58 strbuf_release(sb);
59 sb->buf = buf;
60 sb->len = len;
61 sb->alloc = alloc;
62 strbuf_grow(sb, 0);
63 sb->buf[sb->len] = '\0';
64 }
65
66 void strbuf_grow(struct strbuf *sb, size_t extra)
67 {
68 int new_buf = !sb->alloc;
69 if (unsigned_add_overflows(extra, 1) ||
70 unsigned_add_overflows(sb->len, extra + 1))
71 die("you want to use way too much memory");
72 if (new_buf)
73 sb->buf = NULL;
74 ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
75 if (new_buf)
76 sb->buf[0] = '\0';
77 }
78
79 void strbuf_trim(struct strbuf *sb)
80 {
81 char *b = sb->buf;
82 while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
83 sb->len--;
84 while (sb->len > 0 && isspace(*b)) {
85 b++;
86 sb->len--;
87 }
88 memmove(sb->buf, b, sb->len);
89 sb->buf[sb->len] = '\0';
90 }
91 void strbuf_rtrim(struct strbuf *sb)
92 {
93 while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
94 sb->len--;
95 sb->buf[sb->len] = '\0';
96 }
97
98 void strbuf_ltrim(struct strbuf *sb)
99 {
100 char *b = sb->buf;
101 while (sb->len > 0 && isspace(*b)) {
102 b++;
103 sb->len--;
104 }
105 memmove(sb->buf, b, sb->len);
106 sb->buf[sb->len] = '\0';
107 }
108
109 struct strbuf **strbuf_split_buf(const char *str, size_t slen, int delim, int max)
110 {
111 int alloc = 2, pos = 0;
112 const char *n, *p;
113 struct strbuf **ret;
114 struct strbuf *t;
115
116 ret = xcalloc(alloc, sizeof(struct strbuf *));
117 p = n = str;
118 while (n < str + slen) {
119 int len;
120 if (max <= 0 || pos + 1 < max)
121 n = memchr(n, delim, slen - (n - str));
122 else
123 n = NULL;
124 if (pos + 1 >= alloc) {
125 alloc = alloc * 2;
126 ret = xrealloc(ret, sizeof(struct strbuf *) * alloc);
127 }
128 if (!n)
129 n = str + slen - 1;
130 len = n - p + 1;
131 t = xmalloc(sizeof(struct strbuf));
132 strbuf_init(t, len);
133 strbuf_add(t, p, len);
134 ret[pos] = t;
135 ret[++pos] = NULL;
136 p = ++n;
137 }
138 return ret;
139 }
140
141 void strbuf_list_free(struct strbuf **sbs)
142 {
143 struct strbuf **s = sbs;
144
145 while (*s) {
146 strbuf_release(*s);
147 free(*s++);
148 }
149 free(sbs);
150 }
151
152 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
153 {
154 int len = a->len < b->len ? a->len: b->len;
155 int cmp = memcmp(a->buf, b->buf, len);
156 if (cmp)
157 return cmp;
158 return a->len < b->len ? -1: a->len != b->len;
159 }
160
161 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
162 const void *data, size_t dlen)
163 {
164 if (unsigned_add_overflows(pos, len))
165 die("you want to use way too much memory");
166 if (pos > sb->len)
167 die("`pos' is too far after the end of the buffer");
168 if (pos + len > sb->len)
169 die("`pos + len' is too far after the end of the buffer");
170
171 if (dlen >= len)
172 strbuf_grow(sb, dlen - len);
173 memmove(sb->buf + pos + dlen,
174 sb->buf + pos + len,
175 sb->len - pos - len);
176 memcpy(sb->buf + pos, data, dlen);
177 strbuf_setlen(sb, sb->len + dlen - len);
178 }
179
180 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
181 {
182 strbuf_splice(sb, pos, 0, data, len);
183 }
184
185 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
186 {
187 strbuf_splice(sb, pos, len, NULL, 0);
188 }
189
190 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
191 {
192 strbuf_grow(sb, len);
193 memcpy(sb->buf + sb->len, data, len);
194 strbuf_setlen(sb, sb->len + len);
195 }
196
197 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
198 {
199 strbuf_grow(sb, len);
200 memcpy(sb->buf + sb->len, sb->buf + pos, len);
201 strbuf_setlen(sb, sb->len + len);
202 }
203
204 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
205 {
206 va_list ap;
207 va_start(ap, fmt);
208 strbuf_vaddf(sb, fmt, ap);
209 va_end(ap);
210 }
211
212 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
213 {
214 int len;
215 va_list cp;
216
217 if (!strbuf_avail(sb))
218 strbuf_grow(sb, 64);
219 va_copy(cp, ap);
220 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
221 va_end(cp);
222 if (len < 0)
223 die("BUG: your vsnprintf is broken (returned %d)", len);
224 if (len > strbuf_avail(sb)) {
225 strbuf_grow(sb, len);
226 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
227 if (len > strbuf_avail(sb))
228 die("BUG: your vsnprintf is broken (insatiable)");
229 }
230 strbuf_setlen(sb, sb->len + len);
231 }
232
233 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
234 void *context)
235 {
236 for (;;) {
237 const char *percent;
238 size_t consumed;
239
240 percent = strchrnul(format, '%');
241 strbuf_add(sb, format, percent - format);
242 if (!*percent)
243 break;
244 format = percent + 1;
245
246 if (*format == '%') {
247 strbuf_addch(sb, '%');
248 format++;
249 continue;
250 }
251
252 consumed = fn(sb, format, context);
253 if (consumed)
254 format += consumed;
255 else
256 strbuf_addch(sb, '%');
257 }
258 }
259
260 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
261 void *context)
262 {
263 struct strbuf_expand_dict_entry *e = context;
264 size_t len;
265
266 for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
267 if (!strncmp(placeholder, e->placeholder, len)) {
268 if (e->value)
269 strbuf_addstr(sb, e->value);
270 return len;
271 }
272 }
273 return 0;
274 }
275
276 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
277 {
278 int i, len = src->len;
279
280 for (i = 0; i < len; i++) {
281 if (src->buf[i] == '%')
282 strbuf_addch(dst, '%');
283 strbuf_addch(dst, src->buf[i]);
284 }
285 }
286
287 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
288 {
289 size_t res;
290 size_t oldalloc = sb->alloc;
291
292 strbuf_grow(sb, size);
293 res = fread(sb->buf + sb->len, 1, size, f);
294 if (res > 0)
295 strbuf_setlen(sb, sb->len + res);
296 else if (oldalloc == 0)
297 strbuf_release(sb);
298 return res;
299 }
300
301 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
302 {
303 size_t oldlen = sb->len;
304 size_t oldalloc = sb->alloc;
305
306 strbuf_grow(sb, hint ? hint : 8192);
307 for (;;) {
308 ssize_t cnt;
309
310 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
311 if (cnt < 0) {
312 if (oldalloc == 0)
313 strbuf_release(sb);
314 else
315 strbuf_setlen(sb, oldlen);
316 return -1;
317 }
318 if (!cnt)
319 break;
320 sb->len += cnt;
321 strbuf_grow(sb, 8192);
322 }
323
324 sb->buf[sb->len] = '\0';
325 return sb->len - oldlen;
326 }
327
328 #define STRBUF_MAXLINK (2*PATH_MAX)
329
330 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
331 {
332 size_t oldalloc = sb->alloc;
333
334 if (hint < 32)
335 hint = 32;
336
337 while (hint < STRBUF_MAXLINK) {
338 int len;
339
340 strbuf_grow(sb, hint);
341 len = readlink(path, sb->buf, hint);
342 if (len < 0) {
343 if (errno != ERANGE)
344 break;
345 } else if (len < hint) {
346 strbuf_setlen(sb, len);
347 return 0;
348 }
349
350 /* .. the buffer was too small - try again */
351 hint *= 2;
352 }
353 if (oldalloc == 0)
354 strbuf_release(sb);
355 return -1;
356 }
357
358 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
359 {
360 int ch;
361
362 if (feof(fp))
363 return EOF;
364
365 strbuf_reset(sb);
366 while ((ch = fgetc(fp)) != EOF) {
367 strbuf_grow(sb, 1);
368 sb->buf[sb->len++] = ch;
369 if (ch == term)
370 break;
371 }
372 if (ch == EOF && sb->len == 0)
373 return EOF;
374
375 sb->buf[sb->len] = '\0';
376 return 0;
377 }
378
379 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
380 {
381 if (strbuf_getwholeline(sb, fp, term))
382 return EOF;
383 if (sb->buf[sb->len-1] == term)
384 strbuf_setlen(sb, sb->len-1);
385 return 0;
386 }
387
388 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
389 {
390 strbuf_reset(sb);
391
392 while (1) {
393 char ch;
394 ssize_t len = xread(fd, &ch, 1);
395 if (len <= 0)
396 return EOF;
397 strbuf_addch(sb, ch);
398 if (ch == term)
399 break;
400 }
401 return 0;
402 }
403
404 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
405 {
406 int fd, len;
407
408 fd = open(path, O_RDONLY);
409 if (fd < 0)
410 return -1;
411 len = strbuf_read(sb, fd, hint);
412 close(fd);
413 if (len < 0)
414 return -1;
415
416 return len;
417 }
418
419 void strbuf_add_lines(struct strbuf *out, const char *prefix,
420 const char *buf, size_t size)
421 {
422 while (size) {
423 const char *next = memchr(buf, '\n', size);
424 next = next ? (next + 1) : (buf + size);
425 strbuf_addstr(out, prefix);
426 strbuf_add(out, buf, next - buf);
427 size -= next - buf;
428 buf = next;
429 }
430 strbuf_complete_line(out);
431 }
432
433 static int is_rfc3986_reserved(char ch)
434 {
435 switch (ch) {
436 case '!': case '*': case '\'': case '(': case ')': case ';':
437 case ':': case '@': case '&': case '=': case '+': case '$':
438 case ',': case '/': case '?': case '#': case '[': case ']':
439 return 1;
440 }
441 return 0;
442 }
443
444 static int is_rfc3986_unreserved(char ch)
445 {
446 return isalnum(ch) ||
447 ch == '-' || ch == '_' || ch == '.' || ch == '~';
448 }
449
450 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
451 int reserved)
452 {
453 strbuf_grow(sb, len);
454 while (len--) {
455 char ch = *s++;
456 if (is_rfc3986_unreserved(ch) ||
457 (!reserved && is_rfc3986_reserved(ch)))
458 strbuf_addch(sb, ch);
459 else
460 strbuf_addf(sb, "%%%02x", ch);
461 }
462 }
463
464 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
465 int reserved)
466 {
467 strbuf_add_urlencode(sb, s, strlen(s), reserved);
468 }
469
470 int printf_ln(const char *fmt, ...)
471 {
472 int ret;
473 va_list ap;
474 va_start(ap, fmt);
475 ret = vprintf(fmt, ap);
476 va_end(ap);
477 if (ret < 0 || putchar('\n') == EOF)
478 return -1;
479 return ret + 1;
480 }
481
482 int fprintf_ln(FILE *fp, const char *fmt, ...)
483 {
484 int ret;
485 va_list ap;
486 va_start(ap, fmt);
487 ret = vfprintf(fp, fmt, ap);
488 va_end(ap);
489 if (ret < 0 || putc('\n', fp) == EOF)
490 return -1;
491 return ret + 1;
492 }