Merge branch 'rs/strbuf-read-once-reset-length'
[git/git.git] / strbuf.c
1 #include "cache.h"
2 #include "refs.h"
3 #include "utf8.h"
4
5 int starts_with(const char *str, const char *prefix)
6 {
7 for (; ; str++, prefix++)
8 if (!*prefix)
9 return 1;
10 else if (*str != *prefix)
11 return 0;
12 }
13
14 /*
15 * Used as the default ->buf value, so that people can always assume
16 * buf is non NULL and ->buf is NUL terminated even for a freshly
17 * initialized strbuf.
18 */
19 char strbuf_slopbuf[1];
20
21 void strbuf_init(struct strbuf *sb, size_t hint)
22 {
23 sb->alloc = sb->len = 0;
24 sb->buf = strbuf_slopbuf;
25 if (hint)
26 strbuf_grow(sb, hint);
27 }
28
29 void strbuf_release(struct strbuf *sb)
30 {
31 if (sb->alloc) {
32 free(sb->buf);
33 strbuf_init(sb, 0);
34 }
35 }
36
37 char *strbuf_detach(struct strbuf *sb, size_t *sz)
38 {
39 char *res;
40 strbuf_grow(sb, 0);
41 res = sb->buf;
42 if (sz)
43 *sz = sb->len;
44 strbuf_init(sb, 0);
45 return res;
46 }
47
48 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
49 {
50 strbuf_release(sb);
51 sb->buf = buf;
52 sb->len = len;
53 sb->alloc = alloc;
54 strbuf_grow(sb, 0);
55 sb->buf[sb->len] = '\0';
56 }
57
58 void strbuf_grow(struct strbuf *sb, size_t extra)
59 {
60 int new_buf = !sb->alloc;
61 if (unsigned_add_overflows(extra, 1) ||
62 unsigned_add_overflows(sb->len, extra + 1))
63 die("you want to use way too much memory");
64 if (new_buf)
65 sb->buf = NULL;
66 ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
67 if (new_buf)
68 sb->buf[0] = '\0';
69 }
70
71 void strbuf_trim(struct strbuf *sb)
72 {
73 strbuf_rtrim(sb);
74 strbuf_ltrim(sb);
75 }
76 void strbuf_rtrim(struct strbuf *sb)
77 {
78 while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
79 sb->len--;
80 sb->buf[sb->len] = '\0';
81 }
82
83 void strbuf_ltrim(struct strbuf *sb)
84 {
85 char *b = sb->buf;
86 while (sb->len > 0 && isspace(*b)) {
87 b++;
88 sb->len--;
89 }
90 memmove(sb->buf, b, sb->len);
91 sb->buf[sb->len] = '\0';
92 }
93
94 int strbuf_reencode(struct strbuf *sb, const char *from, const char *to)
95 {
96 char *out;
97 int len;
98
99 if (same_encoding(from, to))
100 return 0;
101
102 out = reencode_string_len(sb->buf, sb->len, to, from, &len);
103 if (!out)
104 return -1;
105
106 strbuf_attach(sb, out, len, len);
107 return 0;
108 }
109
110 void strbuf_tolower(struct strbuf *sb)
111 {
112 char *p = sb->buf, *end = sb->buf + sb->len;
113 for (; p < end; p++)
114 *p = tolower(*p);
115 }
116
117 struct strbuf **strbuf_split_buf(const char *str, size_t slen,
118 int terminator, int max)
119 {
120 struct strbuf **ret = NULL;
121 size_t nr = 0, alloc = 0;
122 struct strbuf *t;
123
124 while (slen) {
125 int len = slen;
126 if (max <= 0 || nr + 1 < max) {
127 const char *end = memchr(str, terminator, slen);
128 if (end)
129 len = end - str + 1;
130 }
131 t = xmalloc(sizeof(struct strbuf));
132 strbuf_init(t, len);
133 strbuf_add(t, str, len);
134 ALLOC_GROW(ret, nr + 2, alloc);
135 ret[nr++] = t;
136 str += len;
137 slen -= len;
138 }
139 ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
140 ret[nr] = NULL;
141 return ret;
142 }
143
144 void strbuf_list_free(struct strbuf **sbs)
145 {
146 struct strbuf **s = sbs;
147
148 while (*s) {
149 strbuf_release(*s);
150 free(*s++);
151 }
152 free(sbs);
153 }
154
155 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
156 {
157 int len = a->len < b->len ? a->len: b->len;
158 int cmp = memcmp(a->buf, b->buf, len);
159 if (cmp)
160 return cmp;
161 return a->len < b->len ? -1: a->len != b->len;
162 }
163
164 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
165 const void *data, size_t dlen)
166 {
167 if (unsigned_add_overflows(pos, len))
168 die("you want to use way too much memory");
169 if (pos > sb->len)
170 die("`pos' is too far after the end of the buffer");
171 if (pos + len > sb->len)
172 die("`pos + len' is too far after the end of the buffer");
173
174 if (dlen >= len)
175 strbuf_grow(sb, dlen - len);
176 memmove(sb->buf + pos + dlen,
177 sb->buf + pos + len,
178 sb->len - pos - len);
179 memcpy(sb->buf + pos, data, dlen);
180 strbuf_setlen(sb, sb->len + dlen - len);
181 }
182
183 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
184 {
185 strbuf_splice(sb, pos, 0, data, len);
186 }
187
188 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
189 {
190 strbuf_splice(sb, pos, len, "", 0);
191 }
192
193 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
194 {
195 strbuf_grow(sb, len);
196 memcpy(sb->buf + sb->len, data, len);
197 strbuf_setlen(sb, sb->len + len);
198 }
199
200 void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
201 {
202 strbuf_grow(sb, sb2->len);
203 memcpy(sb->buf + sb->len, sb2->buf, sb2->len);
204 strbuf_setlen(sb, sb->len + sb2->len);
205 }
206
207 void strbuf_addchars(struct strbuf *sb, int c, size_t n)
208 {
209 strbuf_grow(sb, n);
210 memset(sb->buf + sb->len, c, n);
211 strbuf_setlen(sb, sb->len + n);
212 }
213
214 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
215 {
216 va_list ap;
217 va_start(ap, fmt);
218 strbuf_vaddf(sb, fmt, ap);
219 va_end(ap);
220 }
221
222 static void add_lines(struct strbuf *out,
223 const char *prefix1,
224 const char *prefix2,
225 const char *buf, size_t size)
226 {
227 while (size) {
228 const char *prefix;
229 const char *next = memchr(buf, '\n', size);
230 next = next ? (next + 1) : (buf + size);
231
232 prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
233 ? prefix2 : prefix1);
234 strbuf_addstr(out, prefix);
235 strbuf_add(out, buf, next - buf);
236 size -= next - buf;
237 buf = next;
238 }
239 strbuf_complete_line(out);
240 }
241
242 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
243 {
244 static char prefix1[3];
245 static char prefix2[2];
246
247 if (prefix1[0] != comment_line_char) {
248 xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
249 xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
250 }
251 add_lines(out, prefix1, prefix2, buf, size);
252 }
253
254 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
255 {
256 va_list params;
257 struct strbuf buf = STRBUF_INIT;
258 int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
259
260 va_start(params, fmt);
261 strbuf_vaddf(&buf, fmt, params);
262 va_end(params);
263
264 strbuf_add_commented_lines(sb, buf.buf, buf.len);
265 if (incomplete_line)
266 sb->buf[--sb->len] = '\0';
267
268 strbuf_release(&buf);
269 }
270
271 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
272 {
273 int len;
274 va_list cp;
275
276 if (!strbuf_avail(sb))
277 strbuf_grow(sb, 64);
278 va_copy(cp, ap);
279 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
280 va_end(cp);
281 if (len < 0)
282 die("BUG: your vsnprintf is broken (returned %d)", len);
283 if (len > strbuf_avail(sb)) {
284 strbuf_grow(sb, len);
285 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
286 if (len > strbuf_avail(sb))
287 die("BUG: your vsnprintf is broken (insatiable)");
288 }
289 strbuf_setlen(sb, sb->len + len);
290 }
291
292 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
293 void *context)
294 {
295 for (;;) {
296 const char *percent;
297 size_t consumed;
298
299 percent = strchrnul(format, '%');
300 strbuf_add(sb, format, percent - format);
301 if (!*percent)
302 break;
303 format = percent + 1;
304
305 if (*format == '%') {
306 strbuf_addch(sb, '%');
307 format++;
308 continue;
309 }
310
311 consumed = fn(sb, format, context);
312 if (consumed)
313 format += consumed;
314 else
315 strbuf_addch(sb, '%');
316 }
317 }
318
319 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
320 void *context)
321 {
322 struct strbuf_expand_dict_entry *e = context;
323 size_t len;
324
325 for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
326 if (!strncmp(placeholder, e->placeholder, len)) {
327 if (e->value)
328 strbuf_addstr(sb, e->value);
329 return len;
330 }
331 }
332 return 0;
333 }
334
335 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
336 {
337 int i, len = src->len;
338
339 for (i = 0; i < len; i++) {
340 if (src->buf[i] == '%')
341 strbuf_addch(dst, '%');
342 strbuf_addch(dst, src->buf[i]);
343 }
344 }
345
346 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
347 {
348 size_t res;
349 size_t oldalloc = sb->alloc;
350
351 strbuf_grow(sb, size);
352 res = fread(sb->buf + sb->len, 1, size, f);
353 if (res > 0)
354 strbuf_setlen(sb, sb->len + res);
355 else if (oldalloc == 0)
356 strbuf_release(sb);
357 return res;
358 }
359
360 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
361 {
362 size_t oldlen = sb->len;
363 size_t oldalloc = sb->alloc;
364
365 strbuf_grow(sb, hint ? hint : 8192);
366 for (;;) {
367 ssize_t want = sb->alloc - sb->len - 1;
368 ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
369
370 if (got < 0) {
371 if (oldalloc == 0)
372 strbuf_release(sb);
373 else
374 strbuf_setlen(sb, oldlen);
375 return -1;
376 }
377 sb->len += got;
378 if (got < want)
379 break;
380 strbuf_grow(sb, 8192);
381 }
382
383 sb->buf[sb->len] = '\0';
384 return sb->len - oldlen;
385 }
386
387 ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
388 {
389 size_t oldalloc = sb->alloc;
390 ssize_t cnt;
391
392 strbuf_grow(sb, hint ? hint : 8192);
393 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
394 if (cnt > 0)
395 strbuf_setlen(sb, sb->len + cnt);
396 else if (oldalloc == 0)
397 strbuf_release(sb);
398 return cnt;
399 }
400
401 ssize_t strbuf_write(struct strbuf *sb, FILE *f)
402 {
403 return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
404 }
405
406
407 #define STRBUF_MAXLINK (2*PATH_MAX)
408
409 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
410 {
411 size_t oldalloc = sb->alloc;
412
413 if (hint < 32)
414 hint = 32;
415
416 while (hint < STRBUF_MAXLINK) {
417 int len;
418
419 strbuf_grow(sb, hint);
420 len = readlink(path, sb->buf, hint);
421 if (len < 0) {
422 if (errno != ERANGE)
423 break;
424 } else if (len < hint) {
425 strbuf_setlen(sb, len);
426 return 0;
427 }
428
429 /* .. the buffer was too small - try again */
430 hint *= 2;
431 }
432 if (oldalloc == 0)
433 strbuf_release(sb);
434 return -1;
435 }
436
437 int strbuf_getcwd(struct strbuf *sb)
438 {
439 size_t oldalloc = sb->alloc;
440 size_t guessed_len = 128;
441
442 for (;; guessed_len *= 2) {
443 strbuf_grow(sb, guessed_len);
444 if (getcwd(sb->buf, sb->alloc)) {
445 strbuf_setlen(sb, strlen(sb->buf));
446 return 0;
447 }
448
449 /*
450 * If getcwd(3) is implemented as a syscall that falls
451 * back to a regular lookup using readdir(3) etc. then
452 * we may be able to avoid EACCES by providing enough
453 * space to the syscall as it's not necessarily bound
454 * to the same restrictions as the fallback.
455 */
456 if (errno == EACCES && guessed_len < PATH_MAX)
457 continue;
458
459 if (errno != ERANGE)
460 break;
461 }
462 if (oldalloc == 0)
463 strbuf_release(sb);
464 else
465 strbuf_reset(sb);
466 return -1;
467 }
468
469 #ifdef HAVE_GETDELIM
470 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
471 {
472 ssize_t r;
473
474 if (feof(fp))
475 return EOF;
476
477 strbuf_reset(sb);
478
479 /* Translate slopbuf to NULL, as we cannot call realloc on it */
480 if (!sb->alloc)
481 sb->buf = NULL;
482 errno = 0;
483 r = getdelim(&sb->buf, &sb->alloc, term, fp);
484
485 if (r > 0) {
486 sb->len = r;
487 return 0;
488 }
489 assert(r == -1);
490
491 /*
492 * Normally we would have called xrealloc, which will try to free
493 * memory and recover. But we have no way to tell getdelim() to do so.
494 * Worse, we cannot try to recover ENOMEM ourselves, because we have
495 * no idea how many bytes were read by getdelim.
496 *
497 * Dying here is reasonable. It mirrors what xrealloc would do on
498 * catastrophic memory failure. We skip the opportunity to free pack
499 * memory and retry, but that's unlikely to help for a malloc small
500 * enough to hold a single line of input, anyway.
501 */
502 if (errno == ENOMEM)
503 die("Out of memory, getdelim failed");
504
505 /*
506 * Restore strbuf invariants; if getdelim left us with a NULL pointer,
507 * we can just re-init, but otherwise we should make sure that our
508 * length is empty, and that the result is NUL-terminated.
509 */
510 if (!sb->buf)
511 strbuf_init(sb, 0);
512 else
513 strbuf_reset(sb);
514 return EOF;
515 }
516 #else
517 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
518 {
519 int ch;
520
521 if (feof(fp))
522 return EOF;
523
524 strbuf_reset(sb);
525 flockfile(fp);
526 while ((ch = getc_unlocked(fp)) != EOF) {
527 if (!strbuf_avail(sb))
528 strbuf_grow(sb, 1);
529 sb->buf[sb->len++] = ch;
530 if (ch == term)
531 break;
532 }
533 funlockfile(fp);
534 if (ch == EOF && sb->len == 0)
535 return EOF;
536
537 sb->buf[sb->len] = '\0';
538 return 0;
539 }
540 #endif
541
542 static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
543 {
544 if (strbuf_getwholeline(sb, fp, term))
545 return EOF;
546 if (sb->buf[sb->len - 1] == term)
547 strbuf_setlen(sb, sb->len - 1);
548 return 0;
549 }
550
551 int strbuf_getline(struct strbuf *sb, FILE *fp)
552 {
553 if (strbuf_getwholeline(sb, fp, '\n'))
554 return EOF;
555 if (sb->buf[sb->len - 1] == '\n') {
556 strbuf_setlen(sb, sb->len - 1);
557 if (sb->len && sb->buf[sb->len - 1] == '\r')
558 strbuf_setlen(sb, sb->len - 1);
559 }
560 return 0;
561 }
562
563 int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
564 {
565 return strbuf_getdelim(sb, fp, '\n');
566 }
567
568 int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
569 {
570 return strbuf_getdelim(sb, fp, '\0');
571 }
572
573 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
574 {
575 strbuf_reset(sb);
576
577 while (1) {
578 char ch;
579 ssize_t len = xread(fd, &ch, 1);
580 if (len <= 0)
581 return EOF;
582 strbuf_addch(sb, ch);
583 if (ch == term)
584 break;
585 }
586 return 0;
587 }
588
589 ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
590 {
591 int fd;
592 ssize_t len;
593
594 fd = open(path, O_RDONLY);
595 if (fd < 0)
596 return -1;
597 len = strbuf_read(sb, fd, hint);
598 close(fd);
599 if (len < 0)
600 return -1;
601
602 return len;
603 }
604
605 void strbuf_add_lines(struct strbuf *out, const char *prefix,
606 const char *buf, size_t size)
607 {
608 add_lines(out, prefix, NULL, buf, size);
609 }
610
611 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
612 {
613 while (*s) {
614 size_t len = strcspn(s, "\"<>&");
615 strbuf_add(buf, s, len);
616 s += len;
617 switch (*s) {
618 case '"':
619 strbuf_addstr(buf, "&quot;");
620 break;
621 case '<':
622 strbuf_addstr(buf, "&lt;");
623 break;
624 case '>':
625 strbuf_addstr(buf, "&gt;");
626 break;
627 case '&':
628 strbuf_addstr(buf, "&amp;");
629 break;
630 case 0:
631 return;
632 }
633 s++;
634 }
635 }
636
637 static int is_rfc3986_reserved(char ch)
638 {
639 switch (ch) {
640 case '!': case '*': case '\'': case '(': case ')': case ';':
641 case ':': case '@': case '&': case '=': case '+': case '$':
642 case ',': case '/': case '?': case '#': case '[': case ']':
643 return 1;
644 }
645 return 0;
646 }
647
648 static int is_rfc3986_unreserved(char ch)
649 {
650 return isalnum(ch) ||
651 ch == '-' || ch == '_' || ch == '.' || ch == '~';
652 }
653
654 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
655 int reserved)
656 {
657 strbuf_grow(sb, len);
658 while (len--) {
659 char ch = *s++;
660 if (is_rfc3986_unreserved(ch) ||
661 (!reserved && is_rfc3986_reserved(ch)))
662 strbuf_addch(sb, ch);
663 else
664 strbuf_addf(sb, "%%%02x", ch);
665 }
666 }
667
668 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
669 int reserved)
670 {
671 strbuf_add_urlencode(sb, s, strlen(s), reserved);
672 }
673
674 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
675 {
676 if (bytes > 1 << 30) {
677 strbuf_addf(buf, "%u.%2.2u GiB",
678 (int)(bytes >> 30),
679 (int)(bytes & ((1 << 30) - 1)) / 10737419);
680 } else if (bytes > 1 << 20) {
681 int x = bytes + 5243; /* for rounding */
682 strbuf_addf(buf, "%u.%2.2u MiB",
683 x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
684 } else if (bytes > 1 << 10) {
685 int x = bytes + 5; /* for rounding */
686 strbuf_addf(buf, "%u.%2.2u KiB",
687 x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
688 } else {
689 strbuf_addf(buf, "%u bytes", (int)bytes);
690 }
691 }
692
693 void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
694 {
695 if (!*path)
696 die("The empty string is not a valid path");
697 if (!is_absolute_path(path)) {
698 struct stat cwd_stat, pwd_stat;
699 size_t orig_len = sb->len;
700 char *cwd = xgetcwd();
701 char *pwd = getenv("PWD");
702 if (pwd && strcmp(pwd, cwd) &&
703 !stat(cwd, &cwd_stat) &&
704 (cwd_stat.st_dev || cwd_stat.st_ino) &&
705 !stat(pwd, &pwd_stat) &&
706 pwd_stat.st_dev == cwd_stat.st_dev &&
707 pwd_stat.st_ino == cwd_stat.st_ino)
708 strbuf_addstr(sb, pwd);
709 else
710 strbuf_addstr(sb, cwd);
711 if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
712 strbuf_addch(sb, '/');
713 free(cwd);
714 }
715 strbuf_addstr(sb, path);
716 }
717
718 void strbuf_add_real_path(struct strbuf *sb, const char *path)
719 {
720 if (sb->len) {
721 struct strbuf resolved = STRBUF_INIT;
722 strbuf_realpath(&resolved, path, 1);
723 strbuf_addbuf(sb, &resolved);
724 strbuf_release(&resolved);
725 } else
726 strbuf_realpath(sb, path, 1);
727 }
728
729 int printf_ln(const char *fmt, ...)
730 {
731 int ret;
732 va_list ap;
733 va_start(ap, fmt);
734 ret = vprintf(fmt, ap);
735 va_end(ap);
736 if (ret < 0 || putchar('\n') == EOF)
737 return -1;
738 return ret + 1;
739 }
740
741 int fprintf_ln(FILE *fp, const char *fmt, ...)
742 {
743 int ret;
744 va_list ap;
745 va_start(ap, fmt);
746 ret = vfprintf(fp, fmt, ap);
747 va_end(ap);
748 if (ret < 0 || putc('\n', fp) == EOF)
749 return -1;
750 return ret + 1;
751 }
752
753 char *xstrdup_tolower(const char *string)
754 {
755 char *result;
756 size_t len, i;
757
758 len = strlen(string);
759 result = xmallocz(len);
760 for (i = 0; i < len; i++)
761 result[i] = tolower(string[i]);
762 result[i] = '\0';
763 return result;
764 }
765
766 char *xstrvfmt(const char *fmt, va_list ap)
767 {
768 struct strbuf buf = STRBUF_INIT;
769 strbuf_vaddf(&buf, fmt, ap);
770 return strbuf_detach(&buf, NULL);
771 }
772
773 char *xstrfmt(const char *fmt, ...)
774 {
775 va_list ap;
776 char *ret;
777
778 va_start(ap, fmt);
779 ret = xstrvfmt(fmt, ap);
780 va_end(ap);
781
782 return ret;
783 }
784
785 void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
786 int tz_offset, int suppress_tz_name)
787 {
788 struct strbuf munged_fmt = STRBUF_INIT;
789 size_t hint = 128;
790 size_t len;
791
792 if (!*fmt)
793 return;
794
795 /*
796 * There is no portable way to pass timezone information to
797 * strftime, so we handle %z and %Z here.
798 */
799 for (;;) {
800 const char *percent = strchrnul(fmt, '%');
801 strbuf_add(&munged_fmt, fmt, percent - fmt);
802 if (!*percent)
803 break;
804 fmt = percent + 1;
805 switch (*fmt) {
806 case '%':
807 strbuf_addstr(&munged_fmt, "%%");
808 fmt++;
809 break;
810 case 'z':
811 strbuf_addf(&munged_fmt, "%+05d", tz_offset);
812 fmt++;
813 break;
814 case 'Z':
815 if (suppress_tz_name) {
816 fmt++;
817 break;
818 }
819 /* FALLTHROUGH */
820 default:
821 strbuf_addch(&munged_fmt, '%');
822 }
823 }
824 fmt = munged_fmt.buf;
825
826 strbuf_grow(sb, hint);
827 len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
828
829 if (!len) {
830 /*
831 * strftime reports "0" if it could not fit the result in the buffer.
832 * Unfortunately, it also reports "0" if the requested time string
833 * takes 0 bytes. So our strategy is to munge the format so that the
834 * output contains at least one character, and then drop the extra
835 * character before returning.
836 */
837 strbuf_addch(&munged_fmt, ' ');
838 while (!len) {
839 hint *= 2;
840 strbuf_grow(sb, hint);
841 len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
842 munged_fmt.buf, tm);
843 }
844 len--; /* drop munged space */
845 }
846 strbuf_release(&munged_fmt);
847 strbuf_setlen(sb, sb->len + len);
848 }
849
850 void strbuf_add_unique_abbrev(struct strbuf *sb, const unsigned char *sha1,
851 int abbrev_len)
852 {
853 int r;
854 strbuf_grow(sb, GIT_SHA1_HEXSZ + 1);
855 r = find_unique_abbrev_r(sb->buf + sb->len, sha1, abbrev_len);
856 strbuf_setlen(sb, sb->len + r);
857 }
858
859 /*
860 * Returns the length of a line, without trailing spaces.
861 *
862 * If the line ends with newline, it will be removed too.
863 */
864 static size_t cleanup(char *line, size_t len)
865 {
866 while (len) {
867 unsigned char c = line[len - 1];
868 if (!isspace(c))
869 break;
870 len--;
871 }
872
873 return len;
874 }
875
876 /*
877 * Remove empty lines from the beginning and end
878 * and also trailing spaces from every line.
879 *
880 * Turn multiple consecutive empty lines between paragraphs
881 * into just one empty line.
882 *
883 * If the input has only empty lines and spaces,
884 * no output will be produced.
885 *
886 * If last line does not have a newline at the end, one is added.
887 *
888 * Enable skip_comments to skip every line starting with comment
889 * character.
890 */
891 void strbuf_stripspace(struct strbuf *sb, int skip_comments)
892 {
893 int empties = 0;
894 size_t i, j, len, newlen;
895 char *eol;
896
897 /* We may have to add a newline. */
898 strbuf_grow(sb, 1);
899
900 for (i = j = 0; i < sb->len; i += len, j += newlen) {
901 eol = memchr(sb->buf + i, '\n', sb->len - i);
902 len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
903
904 if (skip_comments && len && sb->buf[i] == comment_line_char) {
905 newlen = 0;
906 continue;
907 }
908 newlen = cleanup(sb->buf + i, len);
909
910 /* Not just an empty line? */
911 if (newlen) {
912 if (empties > 0 && j > 0)
913 sb->buf[j++] = '\n';
914 empties = 0;
915 memmove(sb->buf + j, sb->buf + i, newlen);
916 sb->buf[newlen + j++] = '\n';
917 } else {
918 empties++;
919 }
920 }
921
922 strbuf_setlen(sb, j);
923 }
924
925 int strbuf_normalize_path(struct strbuf *src)
926 {
927 struct strbuf dst = STRBUF_INIT;
928
929 strbuf_grow(&dst, src->len);
930 if (normalize_path_copy(dst.buf, src->buf) < 0) {
931 strbuf_release(&dst);
932 return -1;
933 }
934
935 /*
936 * normalize_path does not tell us the new length, so we have to
937 * compute it by looking for the new NUL it placed
938 */
939 strbuf_setlen(&dst, strlen(dst.buf));
940 strbuf_swap(src, &dst);
941 strbuf_release(&dst);
942 return 0;
943 }