Sync with maint
[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 ssize_t cnt;
390
391 strbuf_grow(sb, hint ? hint : 8192);
392 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
393 if (cnt > 0)
394 strbuf_setlen(sb, sb->len + cnt);
395 return cnt;
396 }
397
398 ssize_t strbuf_write(struct strbuf *sb, FILE *f)
399 {
400 return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
401 }
402
403
404 #define STRBUF_MAXLINK (2*PATH_MAX)
405
406 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
407 {
408 size_t oldalloc = sb->alloc;
409
410 if (hint < 32)
411 hint = 32;
412
413 while (hint < STRBUF_MAXLINK) {
414 int len;
415
416 strbuf_grow(sb, hint);
417 len = readlink(path, sb->buf, hint);
418 if (len < 0) {
419 if (errno != ERANGE)
420 break;
421 } else if (len < hint) {
422 strbuf_setlen(sb, len);
423 return 0;
424 }
425
426 /* .. the buffer was too small - try again */
427 hint *= 2;
428 }
429 if (oldalloc == 0)
430 strbuf_release(sb);
431 return -1;
432 }
433
434 int strbuf_getcwd(struct strbuf *sb)
435 {
436 size_t oldalloc = sb->alloc;
437 size_t guessed_len = 128;
438
439 for (;; guessed_len *= 2) {
440 strbuf_grow(sb, guessed_len);
441 if (getcwd(sb->buf, sb->alloc)) {
442 strbuf_setlen(sb, strlen(sb->buf));
443 return 0;
444 }
445
446 /*
447 * If getcwd(3) is implemented as a syscall that falls
448 * back to a regular lookup using readdir(3) etc. then
449 * we may be able to avoid EACCES by providing enough
450 * space to the syscall as it's not necessarily bound
451 * to the same restrictions as the fallback.
452 */
453 if (errno == EACCES && guessed_len < PATH_MAX)
454 continue;
455
456 if (errno != ERANGE)
457 break;
458 }
459 if (oldalloc == 0)
460 strbuf_release(sb);
461 else
462 strbuf_reset(sb);
463 return -1;
464 }
465
466 #ifdef HAVE_GETDELIM
467 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
468 {
469 ssize_t r;
470
471 if (feof(fp))
472 return EOF;
473
474 strbuf_reset(sb);
475
476 /* Translate slopbuf to NULL, as we cannot call realloc on it */
477 if (!sb->alloc)
478 sb->buf = NULL;
479 r = getdelim(&sb->buf, &sb->alloc, term, fp);
480
481 if (r > 0) {
482 sb->len = r;
483 return 0;
484 }
485 assert(r == -1);
486
487 /*
488 * Normally we would have called xrealloc, which will try to free
489 * memory and recover. But we have no way to tell getdelim() to do so.
490 * Worse, we cannot try to recover ENOMEM ourselves, because we have
491 * no idea how many bytes were read by getdelim.
492 *
493 * Dying here is reasonable. It mirrors what xrealloc would do on
494 * catastrophic memory failure. We skip the opportunity to free pack
495 * memory and retry, but that's unlikely to help for a malloc small
496 * enough to hold a single line of input, anyway.
497 */
498 if (errno == ENOMEM)
499 die("Out of memory, getdelim failed");
500
501 /*
502 * Restore strbuf invariants; if getdelim left us with a NULL pointer,
503 * we can just re-init, but otherwise we should make sure that our
504 * length is empty, and that the result is NUL-terminated.
505 */
506 if (!sb->buf)
507 strbuf_init(sb, 0);
508 else
509 strbuf_reset(sb);
510 return EOF;
511 }
512 #else
513 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
514 {
515 int ch;
516
517 if (feof(fp))
518 return EOF;
519
520 strbuf_reset(sb);
521 flockfile(fp);
522 while ((ch = getc_unlocked(fp)) != EOF) {
523 if (!strbuf_avail(sb))
524 strbuf_grow(sb, 1);
525 sb->buf[sb->len++] = ch;
526 if (ch == term)
527 break;
528 }
529 funlockfile(fp);
530 if (ch == EOF && sb->len == 0)
531 return EOF;
532
533 sb->buf[sb->len] = '\0';
534 return 0;
535 }
536 #endif
537
538 static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
539 {
540 if (strbuf_getwholeline(sb, fp, term))
541 return EOF;
542 if (sb->buf[sb->len - 1] == term)
543 strbuf_setlen(sb, sb->len - 1);
544 return 0;
545 }
546
547 int strbuf_getline(struct strbuf *sb, FILE *fp)
548 {
549 if (strbuf_getwholeline(sb, fp, '\n'))
550 return EOF;
551 if (sb->buf[sb->len - 1] == '\n') {
552 strbuf_setlen(sb, sb->len - 1);
553 if (sb->len && sb->buf[sb->len - 1] == '\r')
554 strbuf_setlen(sb, sb->len - 1);
555 }
556 return 0;
557 }
558
559 int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
560 {
561 return strbuf_getdelim(sb, fp, '\n');
562 }
563
564 int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
565 {
566 return strbuf_getdelim(sb, fp, '\0');
567 }
568
569 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
570 {
571 strbuf_reset(sb);
572
573 while (1) {
574 char ch;
575 ssize_t len = xread(fd, &ch, 1);
576 if (len <= 0)
577 return EOF;
578 strbuf_addch(sb, ch);
579 if (ch == term)
580 break;
581 }
582 return 0;
583 }
584
585 ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
586 {
587 int fd;
588 ssize_t len;
589
590 fd = open(path, O_RDONLY);
591 if (fd < 0)
592 return -1;
593 len = strbuf_read(sb, fd, hint);
594 close(fd);
595 if (len < 0)
596 return -1;
597
598 return len;
599 }
600
601 void strbuf_add_lines(struct strbuf *out, const char *prefix,
602 const char *buf, size_t size)
603 {
604 add_lines(out, prefix, NULL, buf, size);
605 }
606
607 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
608 {
609 while (*s) {
610 size_t len = strcspn(s, "\"<>&");
611 strbuf_add(buf, s, len);
612 s += len;
613 switch (*s) {
614 case '"':
615 strbuf_addstr(buf, "&quot;");
616 break;
617 case '<':
618 strbuf_addstr(buf, "&lt;");
619 break;
620 case '>':
621 strbuf_addstr(buf, "&gt;");
622 break;
623 case '&':
624 strbuf_addstr(buf, "&amp;");
625 break;
626 case 0:
627 return;
628 }
629 s++;
630 }
631 }
632
633 static int is_rfc3986_reserved(char ch)
634 {
635 switch (ch) {
636 case '!': case '*': case '\'': case '(': case ')': case ';':
637 case ':': case '@': case '&': case '=': case '+': case '$':
638 case ',': case '/': case '?': case '#': case '[': case ']':
639 return 1;
640 }
641 return 0;
642 }
643
644 static int is_rfc3986_unreserved(char ch)
645 {
646 return isalnum(ch) ||
647 ch == '-' || ch == '_' || ch == '.' || ch == '~';
648 }
649
650 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
651 int reserved)
652 {
653 strbuf_grow(sb, len);
654 while (len--) {
655 char ch = *s++;
656 if (is_rfc3986_unreserved(ch) ||
657 (!reserved && is_rfc3986_reserved(ch)))
658 strbuf_addch(sb, ch);
659 else
660 strbuf_addf(sb, "%%%02x", ch);
661 }
662 }
663
664 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
665 int reserved)
666 {
667 strbuf_add_urlencode(sb, s, strlen(s), reserved);
668 }
669
670 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
671 {
672 if (bytes > 1 << 30) {
673 strbuf_addf(buf, "%u.%2.2u GiB",
674 (int)(bytes >> 30),
675 (int)(bytes & ((1 << 30) - 1)) / 10737419);
676 } else if (bytes > 1 << 20) {
677 int x = bytes + 5243; /* for rounding */
678 strbuf_addf(buf, "%u.%2.2u MiB",
679 x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
680 } else if (bytes > 1 << 10) {
681 int x = bytes + 5; /* for rounding */
682 strbuf_addf(buf, "%u.%2.2u KiB",
683 x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
684 } else {
685 strbuf_addf(buf, "%u bytes", (int)bytes);
686 }
687 }
688
689 void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
690 {
691 if (!*path)
692 die("The empty string is not a valid path");
693 if (!is_absolute_path(path)) {
694 struct stat cwd_stat, pwd_stat;
695 size_t orig_len = sb->len;
696 char *cwd = xgetcwd();
697 char *pwd = getenv("PWD");
698 if (pwd && strcmp(pwd, cwd) &&
699 !stat(cwd, &cwd_stat) &&
700 (cwd_stat.st_dev || cwd_stat.st_ino) &&
701 !stat(pwd, &pwd_stat) &&
702 pwd_stat.st_dev == cwd_stat.st_dev &&
703 pwd_stat.st_ino == cwd_stat.st_ino)
704 strbuf_addstr(sb, pwd);
705 else
706 strbuf_addstr(sb, cwd);
707 if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
708 strbuf_addch(sb, '/');
709 free(cwd);
710 }
711 strbuf_addstr(sb, path);
712 }
713
714 void strbuf_add_real_path(struct strbuf *sb, const char *path)
715 {
716 if (sb->len) {
717 struct strbuf resolved = STRBUF_INIT;
718 strbuf_realpath(&resolved, path, 1);
719 strbuf_addbuf(sb, &resolved);
720 strbuf_release(&resolved);
721 } else
722 strbuf_realpath(sb, path, 1);
723 }
724
725 int printf_ln(const char *fmt, ...)
726 {
727 int ret;
728 va_list ap;
729 va_start(ap, fmt);
730 ret = vprintf(fmt, ap);
731 va_end(ap);
732 if (ret < 0 || putchar('\n') == EOF)
733 return -1;
734 return ret + 1;
735 }
736
737 int fprintf_ln(FILE *fp, const char *fmt, ...)
738 {
739 int ret;
740 va_list ap;
741 va_start(ap, fmt);
742 ret = vfprintf(fp, fmt, ap);
743 va_end(ap);
744 if (ret < 0 || putc('\n', fp) == EOF)
745 return -1;
746 return ret + 1;
747 }
748
749 char *xstrdup_tolower(const char *string)
750 {
751 char *result;
752 size_t len, i;
753
754 len = strlen(string);
755 result = xmallocz(len);
756 for (i = 0; i < len; i++)
757 result[i] = tolower(string[i]);
758 result[i] = '\0';
759 return result;
760 }
761
762 char *xstrvfmt(const char *fmt, va_list ap)
763 {
764 struct strbuf buf = STRBUF_INIT;
765 strbuf_vaddf(&buf, fmt, ap);
766 return strbuf_detach(&buf, NULL);
767 }
768
769 char *xstrfmt(const char *fmt, ...)
770 {
771 va_list ap;
772 char *ret;
773
774 va_start(ap, fmt);
775 ret = xstrvfmt(fmt, ap);
776 va_end(ap);
777
778 return ret;
779 }
780
781 void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
782 int tz_offset, int suppress_tz_name)
783 {
784 struct strbuf munged_fmt = STRBUF_INIT;
785 size_t hint = 128;
786 size_t len;
787
788 if (!*fmt)
789 return;
790
791 /*
792 * There is no portable way to pass timezone information to
793 * strftime, so we handle %z and %Z here.
794 */
795 for (;;) {
796 const char *percent = strchrnul(fmt, '%');
797 strbuf_add(&munged_fmt, fmt, percent - fmt);
798 if (!*percent)
799 break;
800 fmt = percent + 1;
801 switch (*fmt) {
802 case '%':
803 strbuf_addstr(&munged_fmt, "%%");
804 fmt++;
805 break;
806 case 'z':
807 strbuf_addf(&munged_fmt, "%+05d", tz_offset);
808 fmt++;
809 break;
810 case 'Z':
811 if (suppress_tz_name) {
812 fmt++;
813 break;
814 }
815 /* FALLTHROUGH */
816 default:
817 strbuf_addch(&munged_fmt, '%');
818 }
819 }
820 fmt = munged_fmt.buf;
821
822 strbuf_grow(sb, hint);
823 len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
824
825 if (!len) {
826 /*
827 * strftime reports "0" if it could not fit the result in the buffer.
828 * Unfortunately, it also reports "0" if the requested time string
829 * takes 0 bytes. So our strategy is to munge the format so that the
830 * output contains at least one character, and then drop the extra
831 * character before returning.
832 */
833 strbuf_addch(&munged_fmt, ' ');
834 while (!len) {
835 hint *= 2;
836 strbuf_grow(sb, hint);
837 len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
838 munged_fmt.buf, tm);
839 }
840 len--; /* drop munged space */
841 }
842 strbuf_release(&munged_fmt);
843 strbuf_setlen(sb, sb->len + len);
844 }
845
846 void strbuf_add_unique_abbrev(struct strbuf *sb, const unsigned char *sha1,
847 int abbrev_len)
848 {
849 int r;
850 strbuf_grow(sb, GIT_SHA1_HEXSZ + 1);
851 r = find_unique_abbrev_r(sb->buf + sb->len, sha1, abbrev_len);
852 strbuf_setlen(sb, sb->len + r);
853 }
854
855 /*
856 * Returns the length of a line, without trailing spaces.
857 *
858 * If the line ends with newline, it will be removed too.
859 */
860 static size_t cleanup(char *line, size_t len)
861 {
862 while (len) {
863 unsigned char c = line[len - 1];
864 if (!isspace(c))
865 break;
866 len--;
867 }
868
869 return len;
870 }
871
872 /*
873 * Remove empty lines from the beginning and end
874 * and also trailing spaces from every line.
875 *
876 * Turn multiple consecutive empty lines between paragraphs
877 * into just one empty line.
878 *
879 * If the input has only empty lines and spaces,
880 * no output will be produced.
881 *
882 * If last line does not have a newline at the end, one is added.
883 *
884 * Enable skip_comments to skip every line starting with comment
885 * character.
886 */
887 void strbuf_stripspace(struct strbuf *sb, int skip_comments)
888 {
889 int empties = 0;
890 size_t i, j, len, newlen;
891 char *eol;
892
893 /* We may have to add a newline. */
894 strbuf_grow(sb, 1);
895
896 for (i = j = 0; i < sb->len; i += len, j += newlen) {
897 eol = memchr(sb->buf + i, '\n', sb->len - i);
898 len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
899
900 if (skip_comments && len && sb->buf[i] == comment_line_char) {
901 newlen = 0;
902 continue;
903 }
904 newlen = cleanup(sb->buf + i, len);
905
906 /* Not just an empty line? */
907 if (newlen) {
908 if (empties > 0 && j > 0)
909 sb->buf[j++] = '\n';
910 empties = 0;
911 memmove(sb->buf + j, sb->buf + i, newlen);
912 sb->buf[newlen + j++] = '\n';
913 } else {
914 empties++;
915 }
916 }
917
918 strbuf_setlen(sb, j);
919 }
920
921 int strbuf_normalize_path(struct strbuf *src)
922 {
923 struct strbuf dst = STRBUF_INIT;
924
925 strbuf_grow(&dst, src->len);
926 if (normalize_path_copy(dst.buf, src->buf) < 0) {
927 strbuf_release(&dst);
928 return -1;
929 }
930
931 /*
932 * normalize_path does not tell us the new length, so we have to
933 * compute it by looking for the new NUL it placed
934 */
935 strbuf_setlen(&dst, strlen(dst.buf));
936 strbuf_swap(src, &dst);
937 strbuf_release(&dst);
938 return 0;
939 }