strbuf.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "string-list.h"
   4 #include "utf8.h"
   5
   6 int starts_with(const char *str, const char *prefix)
   7 {
   8         for (; ; str++, prefix++)
   9                 if (!*prefix)
  10                         return 1;
  11                 else if (*str != *prefix)
  12                         return 0;
  13 }
  14
  15 int istarts_with(const char *str, const char *prefix)
  16 {
  17         for (; ; str++, prefix++)
  18                 if (!*prefix)
  19                         return 1;
  20                 else if (tolower(*str) != tolower(*prefix))
  21                         return 0;
  22 }
  23
  24 int skip_to_optional_arg_default(const char *str, const char *prefix,
  25                                  const char **arg, const char *def)
  26 {
  27         const char *p;
  28
  29         if (!skip_prefix(str, prefix, &p))
  30                 return 0;
  31
  32         if (!*p) {
  33                 if (arg)
  34                         *arg = def;
  35                 return 1;
  36         }
  37
  38         if (*p != '=')
  39                 return 0;
  40
  41         if (arg)
  42                 *arg = p + 1;
  43         return 1;
  44 }
  45
  46 /*
  47  * Used as the default ->buf value, so that people can always assume
  48  * buf is non NULL and ->buf is NUL terminated even for a freshly
  49  * initialized strbuf.
  50  */
  51 char strbuf_slopbuf[1];
  52
  53 void strbuf_init(struct strbuf *sb, size_t hint)
  54 {
  55         sb->alloc = sb->len = 0;
  56         sb->buf = strbuf_slopbuf;
  57         if (hint)
  58                 strbuf_grow(sb, hint);
  59 }
  60
  61 void strbuf_release(struct strbuf *sb)
  62 {
  63         if (sb->alloc) {
  64                 free(sb->buf);
  65                 strbuf_init(sb, 0);
  66         }
  67 }
  68
  69 char *strbuf_detach(struct strbuf *sb, size_t *sz)
  70 {
  71         char *res;
  72         strbuf_grow(sb, 0);
  73         res = sb->buf;
  74         if (sz)
  75                 *sz = sb->len;
  76         strbuf_init(sb, 0);
  77         return res;
  78 }
  79
  80 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  81 {
  82         strbuf_release(sb);
  83         sb->buf   = buf;
  84         sb->len   = len;
  85         sb->alloc = alloc;
  86         strbuf_grow(sb, 0);
  87         sb->buf[sb->len] = '\0';
  88 }
  89
  90 void strbuf_grow(struct strbuf *sb, size_t extra)
  91 {
  92         int new_buf = !sb->alloc;
  93         if (unsigned_add_overflows(extra, 1) ||
  94             unsigned_add_overflows(sb->len, extra + 1))
  95                 die("you want to use way too much memory");
  96         if (new_buf)
  97                 sb->buf = NULL;
  98         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  99         if (new_buf)
 100                 sb->buf[0] = '\0';
 101 }
 102
 103 void strbuf_trim(struct strbuf *sb)
 104 {
 105         strbuf_rtrim(sb);
 106         strbuf_ltrim(sb);
 107 }
 108
 109 void strbuf_rtrim(struct strbuf *sb)
 110 {
 111         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
 112                 sb->len--;
 113         sb->buf[sb->len] = '\0';
 114 }
 115
 116 void strbuf_trim_trailing_dir_sep(struct strbuf *sb)
 117 {
 118         while (sb->len > 0 && is_dir_sep((unsigned char)sb->buf[sb->len - 1]))
 119                 sb->len--;
 120         sb->buf[sb->len] = '\0';
 121 }
 122
 123 void strbuf_trim_trailing_newline(struct strbuf *sb)
 124 {
 125         if (sb->len > 0 && sb->buf[sb->len - 1] == '\n') {
 126                 if (--sb->len > 0 && sb->buf[sb->len - 1] == '\r')
 127                         --sb->len;
 128                 sb->buf[sb->len] = '\0';
 129         }
 130 }
 131
 132 void strbuf_ltrim(struct strbuf *sb)
 133 {
 134         char *b = sb->buf;
 135         while (sb->len > 0 && isspace(*b)) {
 136                 b++;
 137                 sb->len--;
 138         }
 139         memmove(sb->buf, b, sb->len);
 140         sb->buf[sb->len] = '\0';
 141 }
 142
 143 int strbuf_reencode(struct strbuf *sb, const char *from, const char *to)
 144 {
 145         char *out;
 146         size_t len;
 147
 148         if (same_encoding(from, to))
 149                 return 0;
 150
 151         out = reencode_string_len(sb->buf, sb->len, to, from, &len);
 152         if (!out)
 153                 return -1;
 154
 155         strbuf_attach(sb, out, len, len);
 156         return 0;
 157 }
 158
 159 void strbuf_tolower(struct strbuf *sb)
 160 {
 161         char *p = sb->buf, *end = sb->buf + sb->len;
 162         for (; p < end; p++)
 163                 *p = tolower(*p);
 164 }
 165
 166 struct strbuf **strbuf_split_buf(const char *str, size_t slen,
 167                                  int terminator, int max)
 168 {
 169         struct strbuf **ret = NULL;
 170         size_t nr = 0, alloc = 0;
 171         struct strbuf *t;
 172
 173         while (slen) {
 174                 int len = slen;
 175                 if (max <= 0 || nr + 1 < max) {
 176                         const char *end = memchr(str, terminator, slen);
 177                         if (end)
 178                                 len = end - str + 1;
 179                 }
 180                 t = xmalloc(sizeof(struct strbuf));
 181                 strbuf_init(t, len);
 182                 strbuf_add(t, str, len);
 183                 ALLOC_GROW(ret, nr + 2, alloc);
 184                 ret[nr++] = t;
 185                 str += len;
 186                 slen -= len;
 187         }
 188         ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 189         ret[nr] = NULL;
 190         return ret;
 191 }
 192
 193 void strbuf_add_separated_string_list(struct strbuf *str,
 194                                       const char *sep,
 195                                       struct string_list *slist)
 196 {
 197         struct string_list_item *item;
 198         int sep_needed = 0;
 199
 200         for_each_string_list_item(item, slist) {
 201                 if (sep_needed)
 202                         strbuf_addstr(str, sep);
 203                 strbuf_addstr(str, item->string);
 204                 sep_needed = 1;
 205         }
 206 }
 207
 208 void strbuf_list_free(struct strbuf **sbs)
 209 {
 210         struct strbuf **s = sbs;
 211
 212         while (*s) {
 213                 strbuf_release(*s);
 214                 free(*s++);
 215         }
 216         free(sbs);
 217 }
 218
 219 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 220 {
 221         size_t len = a->len < b->len ? a->len: b->len;
 222         int cmp = memcmp(a->buf, b->buf, len);
 223         if (cmp)
 224                 return cmp;
 225         return a->len < b->len ? -1: a->len != b->len;
 226 }
 227
 228 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 229                                    const void *data, size_t dlen)
 230 {
 231         if (unsigned_add_overflows(pos, len))
 232                 die("you want to use way too much memory");
 233         if (pos > sb->len)
 234                 die("`pos' is too far after the end of the buffer");
 235         if (pos + len > sb->len)
 236                 die("`pos + len' is too far after the end of the buffer");
 237
 238         if (dlen >= len)
 239                 strbuf_grow(sb, dlen - len);
 240         memmove(sb->buf + pos + dlen,
 241                         sb->buf + pos + len,
 242                         sb->len - pos - len);
 243         memcpy(sb->buf + pos, data, dlen);
 244         strbuf_setlen(sb, sb->len + dlen - len);
 245 }
 246
 247 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 248 {
 249         strbuf_splice(sb, pos, 0, data, len);
 250 }
 251
 252 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 253 {
 254         strbuf_splice(sb, pos, len, "", 0);
 255 }
 256
 257 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 258 {
 259         strbuf_grow(sb, len);
 260         memcpy(sb->buf + sb->len, data, len);
 261         strbuf_setlen(sb, sb->len + len);
 262 }
 263
 264 void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
 265 {
 266         strbuf_grow(sb, sb2->len);
 267         memcpy(sb->buf + sb->len, sb2->buf, sb2->len);
 268         strbuf_setlen(sb, sb->len + sb2->len);
 269 }
 270
 271 void strbuf_addchars(struct strbuf *sb, int c, size_t n)
 272 {
 273         strbuf_grow(sb, n);
 274         memset(sb->buf + sb->len, c, n);
 275         strbuf_setlen(sb, sb->len + n);
 276 }
 277
 278 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 279 {
 280         va_list ap;
 281         va_start(ap, fmt);
 282         strbuf_vaddf(sb, fmt, ap);
 283         va_end(ap);
 284 }
 285
 286 static void add_lines(struct strbuf *out,
 287                         const char *prefix1,
 288                         const char *prefix2,
 289                         const char *buf, size_t size)
 290 {
 291         while (size) {
 292                 const char *prefix;
 293                 const char *next = memchr(buf, '\n', size);
 294                 next = next ? (next + 1) : (buf + size);
 295
 296                 prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
 297                           ? prefix2 : prefix1);
 298                 strbuf_addstr(out, prefix);
 299                 strbuf_add(out, buf, next - buf);
 300                 size -= next - buf;
 301                 buf = next;
 302         }
 303         strbuf_complete_line(out);
 304 }
 305
 306 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 307 {
 308         static char prefix1[3];
 309         static char prefix2[2];
 310
 311         if (prefix1[0] != comment_line_char) {
 312                 xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
 313                 xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
 314         }
 315         add_lines(out, prefix1, prefix2, buf, size);
 316 }
 317
 318 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 319 {
 320         va_list params;
 321         struct strbuf buf = STRBUF_INIT;
 322         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 323
 324         va_start(params, fmt);
 325         strbuf_vaddf(&buf, fmt, params);
 326         va_end(params);
 327
 328         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 329         if (incomplete_line)
 330                 sb->buf[--sb->len] = '\0';
 331
 332         strbuf_release(&buf);
 333 }
 334
 335 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 336 {
 337         int len;
 338         va_list cp;
 339
 340         if (!strbuf_avail(sb))
 341                 strbuf_grow(sb, 64);
 342         va_copy(cp, ap);
 343         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 344         va_end(cp);
 345         if (len < 0)
 346                 BUG("your vsnprintf is broken (returned %d)", len);
 347         if (len > strbuf_avail(sb)) {
 348                 strbuf_grow(sb, len);
 349                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 350                 if (len > strbuf_avail(sb))
 351                         BUG("your vsnprintf is broken (insatiable)");
 352         }
 353         strbuf_setlen(sb, sb->len + len);
 354 }
 355
 356 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 357                    void *context)
 358 {
 359         for (;;) {
 360                 const char *percent;
 361                 size_t consumed;
 362
 363                 percent = strchrnul(format, '%');
 364                 strbuf_add(sb, format, percent - format);
 365                 if (!*percent)
 366                         break;
 367                 format = percent + 1;
 368
 369                 if (*format == '%') {
 370                         strbuf_addch(sb, '%');
 371                         format++;
 372                         continue;
 373                 }
 374
 375                 consumed = fn(sb, format, context);
 376                 if (consumed)
 377                         format += consumed;
 378                 else
 379                         strbuf_addch(sb, '%');
 380         }
 381 }
 382
 383 size_t strbuf_expand_literal_cb(struct strbuf *sb,
 384                                 const char *placeholder,
 385                                 void *context)
 386 {
 387         int ch;
 388
 389         switch (placeholder[0]) {
 390         case 'n':               /* newline */
 391                 strbuf_addch(sb, '\n');
 392                 return 1;
 393         case 'x':
 394                 /* %x00 == NUL, %x0a == LF, etc. */
 395                 ch = hex2chr(placeholder + 1);
 396                 if (ch < 0)
 397                         return 0;
 398                 strbuf_addch(sb, ch);
 399                 return 3;
 400         }
 401         return 0;
 402 }
 403
 404 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 405                 void *context)
 406 {
 407         struct strbuf_expand_dict_entry *e = context;
 408         size_t len;
 409
 410         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 411                 if (!strncmp(placeholder, e->placeholder, len)) {
 412                         if (e->value)
 413                                 strbuf_addstr(sb, e->value);
 414                         return len;
 415                 }
 416         }
 417         return 0;
 418 }
 419
 420 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 421 {
 422         size_t i, len = src->len;
 423
 424         for (i = 0; i < len; i++) {
 425                 if (src->buf[i] == '%')
 426                         strbuf_addch(dst, '%');
 427                 strbuf_addch(dst, src->buf[i]);
 428         }
 429 }
 430
 431 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 432 {
 433         size_t res;
 434         size_t oldalloc = sb->alloc;
 435
 436         strbuf_grow(sb, size);
 437         res = fread(sb->buf + sb->len, 1, size, f);
 438         if (res > 0)
 439                 strbuf_setlen(sb, sb->len + res);
 440         else if (oldalloc == 0)
 441                 strbuf_release(sb);
 442         return res;
 443 }
 444
 445 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 446 {
 447         size_t oldlen = sb->len;
 448         size_t oldalloc = sb->alloc;
 449
 450         strbuf_grow(sb, hint ? hint : 8192);
 451         for (;;) {
 452                 ssize_t want = sb->alloc - sb->len - 1;
 453                 ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
 454
 455                 if (got < 0) {
 456                         if (oldalloc == 0)
 457                                 strbuf_release(sb);
 458                         else
 459                                 strbuf_setlen(sb, oldlen);
 460                         return -1;
 461                 }
 462                 sb->len += got;
 463                 if (got < want)
 464                         break;
 465                 strbuf_grow(sb, 8192);
 466         }
 467
 468         sb->buf[sb->len] = '\0';
 469         return sb->len - oldlen;
 470 }
 471
 472 ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
 473 {
 474         size_t oldalloc = sb->alloc;
 475         ssize_t cnt;
 476
 477         strbuf_grow(sb, hint ? hint : 8192);
 478         cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 479         if (cnt > 0)
 480                 strbuf_setlen(sb, sb->len + cnt);
 481         else if (oldalloc == 0)
 482                 strbuf_release(sb);
 483         return cnt;
 484 }
 485
 486 ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 487 {
 488         return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 489 }
 490
 491
 492 #define STRBUF_MAXLINK (2*PATH_MAX)
 493
 494 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 495 {
 496         size_t oldalloc = sb->alloc;
 497
 498         if (hint < 32)
 499                 hint = 32;
 500
 501         while (hint < STRBUF_MAXLINK) {
 502                 ssize_t len;
 503
 504                 strbuf_grow(sb, hint);
 505                 len = readlink(path, sb->buf, hint);
 506                 if (len < 0) {
 507                         if (errno != ERANGE)
 508                                 break;
 509                 } else if (len < hint) {
 510                         strbuf_setlen(sb, len);
 511                         return 0;
 512                 }
 513
 514                 /* .. the buffer was too small - try again */
 515                 hint *= 2;
 516         }
 517         if (oldalloc == 0)
 518                 strbuf_release(sb);
 519         return -1;
 520 }
 521
 522 int strbuf_getcwd(struct strbuf *sb)
 523 {
 524         size_t oldalloc = sb->alloc;
 525         size_t guessed_len = 128;
 526
 527         for (;; guessed_len *= 2) {
 528                 strbuf_grow(sb, guessed_len);
 529                 if (getcwd(sb->buf, sb->alloc)) {
 530                         strbuf_setlen(sb, strlen(sb->buf));
 531                         return 0;
 532                 }
 533
 534                 /*
 535                  * If getcwd(3) is implemented as a syscall that falls
 536                  * back to a regular lookup using readdir(3) etc. then
 537                  * we may be able to avoid EACCES by providing enough
 538                  * space to the syscall as it's not necessarily bound
 539                  * to the same restrictions as the fallback.
 540                  */
 541                 if (errno == EACCES && guessed_len < PATH_MAX)
 542                         continue;
 543
 544                 if (errno != ERANGE)
 545                         break;
 546         }
 547         if (oldalloc == 0)
 548                 strbuf_release(sb);
 549         else
 550                 strbuf_reset(sb);
 551         return -1;
 552 }
 553
 554 #ifdef HAVE_GETDELIM
 555 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 556 {
 557         ssize_t r;
 558
 559         if (feof(fp))
 560                 return EOF;
 561
 562         strbuf_reset(sb);
 563
 564         /* Translate slopbuf to NULL, as we cannot call realloc on it */
 565         if (!sb->alloc)
 566                 sb->buf = NULL;
 567         errno = 0;
 568         r = getdelim(&sb->buf, &sb->alloc, term, fp);
 569
 570         if (r > 0) {
 571                 sb->len = r;
 572                 return 0;
 573         }
 574         assert(r == -1);
 575
 576         /*
 577          * Normally we would have called xrealloc, which will try to free
 578          * memory and recover. But we have no way to tell getdelim() to do so.
 579          * Worse, we cannot try to recover ENOMEM ourselves, because we have
 580          * no idea how many bytes were read by getdelim.
 581          *
 582          * Dying here is reasonable. It mirrors what xrealloc would do on
 583          * catastrophic memory failure. We skip the opportunity to free pack
 584          * memory and retry, but that's unlikely to help for a malloc small
 585          * enough to hold a single line of input, anyway.
 586          */
 587         if (errno == ENOMEM)
 588                 die("Out of memory, getdelim failed");
 589
 590         /*
 591          * Restore strbuf invariants; if getdelim left us with a NULL pointer,
 592          * we can just re-init, but otherwise we should make sure that our
 593          * length is empty, and that the result is NUL-terminated.
 594          */
 595         if (!sb->buf)
 596                 strbuf_init(sb, 0);
 597         else
 598                 strbuf_reset(sb);
 599         return EOF;
 600 }
 601 #else
 602 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 603 {
 604         int ch;
 605
 606         if (feof(fp))
 607                 return EOF;
 608
 609         strbuf_reset(sb);
 610         flockfile(fp);
 611         while ((ch = getc_unlocked(fp)) != EOF) {
 612                 if (!strbuf_avail(sb))
 613                         strbuf_grow(sb, 1);
 614                 sb->buf[sb->len++] = ch;
 615                 if (ch == term)
 616                         break;
 617         }
 618         funlockfile(fp);
 619         if (ch == EOF && sb->len == 0)
 620                 return EOF;
 621
 622         sb->buf[sb->len] = '\0';
 623         return 0;
 624 }
 625 #endif
 626
 627 static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 628 {
 629         if (strbuf_getwholeline(sb, fp, term))
 630                 return EOF;
 631         if (sb->buf[sb->len - 1] == term)
 632                 strbuf_setlen(sb, sb->len - 1);
 633         return 0;
 634 }
 635
 636 int strbuf_getline(struct strbuf *sb, FILE *fp)
 637 {
 638         if (strbuf_getwholeline(sb, fp, '\n'))
 639                 return EOF;
 640         if (sb->buf[sb->len - 1] == '\n') {
 641                 strbuf_setlen(sb, sb->len - 1);
 642                 if (sb->len && sb->buf[sb->len - 1] == '\r')
 643                         strbuf_setlen(sb, sb->len - 1);
 644         }
 645         return 0;
 646 }
 647
 648 int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 649 {
 650         return strbuf_getdelim(sb, fp, '\n');
 651 }
 652
 653 int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 654 {
 655         return strbuf_getdelim(sb, fp, '\0');
 656 }
 657
 658 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 659 {
 660         strbuf_reset(sb);
 661
 662         while (1) {
 663                 char ch;
 664                 ssize_t len = xread(fd, &ch, 1);
 665                 if (len <= 0)
 666                         return EOF;
 667                 strbuf_addch(sb, ch);
 668                 if (ch == term)
 669                         break;
 670         }
 671         return 0;
 672 }
 673
 674 ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 675 {
 676         int fd;
 677         ssize_t len;
 678         int saved_errno;
 679
 680         fd = open(path, O_RDONLY);
 681         if (fd < 0)
 682                 return -1;
 683         len = strbuf_read(sb, fd, hint);
 684         saved_errno = errno;
 685         close(fd);
 686         if (len < 0) {
 687                 errno = saved_errno;
 688                 return -1;
 689         }
 690
 691         return len;
 692 }
 693
 694 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 695                       const char *buf, size_t size)
 696 {
 697         add_lines(out, prefix, NULL, buf, size);
 698 }
 699
 700 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 701 {
 702         while (*s) {
 703                 size_t len = strcspn(s, "\"<>&");
 704                 strbuf_add(buf, s, len);
 705                 s += len;
 706                 switch (*s) {
 707                 case '"':
 708                         strbuf_addstr(buf, "&quot;");
 709                         break;
 710                 case '<':
 711                         strbuf_addstr(buf, "&lt;");
 712                         break;
 713                 case '>':
 714                         strbuf_addstr(buf, "&gt;");
 715                         break;
 716                 case '&':
 717                         strbuf_addstr(buf, "&amp;");
 718                         break;
 719                 case 0:
 720                         return;
 721                 }
 722                 s++;
 723         }
 724 }
 725
 726 static int is_rfc3986_reserved(char ch)
 727 {
 728         switch (ch) {
 729                 case '!': case '*': case '\'': case '(': case ')': case ';':
 730                 case ':': case '@': case '&': case '=': case '+': case '$':
 731                 case ',': case '/': case '?': case '#': case '[': case ']':
 732                         return 1;
 733         }
 734         return 0;
 735 }
 736
 737 static int is_rfc3986_unreserved(char ch)
 738 {
 739         return isalnum(ch) ||
 740                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 741 }
 742
 743 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 744                                  int reserved)
 745 {
 746         strbuf_grow(sb, len);
 747         while (len--) {
 748                 char ch = *s++;
 749                 if (is_rfc3986_unreserved(ch) ||
 750                     (!reserved && is_rfc3986_reserved(ch)))
 751                         strbuf_addch(sb, ch);
 752                 else
 753                         strbuf_addf(sb, "%%%02x", (unsigned char)ch);
 754         }
 755 }
 756
 757 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 758                              int reserved)
 759 {
 760         strbuf_add_urlencode(sb, s, strlen(s), reserved);
 761 }
 762
 763 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 764 {
 765         if (bytes > 1 << 30) {
 766                 strbuf_addf(buf, "%u.%2.2u GiB",
 767                             (unsigned)(bytes >> 30),
 768                             (unsigned)(bytes & ((1 << 30) - 1)) / 10737419);
 769         } else if (bytes > 1 << 20) {
 770                 unsigned x = bytes + 5243;  /* for rounding */
 771                 strbuf_addf(buf, "%u.%2.2u MiB",
 772                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 773         } else if (bytes > 1 << 10) {
 774                 unsigned x = bytes + 5;  /* for rounding */
 775                 strbuf_addf(buf, "%u.%2.2u KiB",
 776                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 777         } else {
 778                 strbuf_addf(buf, "%u bytes", (unsigned)bytes);
 779         }
 780 }
 781
 782 void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 783 {
 784         if (!*path)
 785                 die("The empty string is not a valid path");
 786         if (!is_absolute_path(path)) {
 787                 struct stat cwd_stat, pwd_stat;
 788                 size_t orig_len = sb->len;
 789                 char *cwd = xgetcwd();
 790                 char *pwd = getenv("PWD");
 791                 if (pwd && strcmp(pwd, cwd) &&
 792                     !stat(cwd, &cwd_stat) &&
 793                     (cwd_stat.st_dev || cwd_stat.st_ino) &&
 794                     !stat(pwd, &pwd_stat) &&
 795                     pwd_stat.st_dev == cwd_stat.st_dev &&
 796                     pwd_stat.st_ino == cwd_stat.st_ino)
 797                         strbuf_addstr(sb, pwd);
 798                 else
 799                         strbuf_addstr(sb, cwd);
 800                 if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 801                         strbuf_addch(sb, '/');
 802                 free(cwd);
 803         }
 804         strbuf_addstr(sb, path);
 805 }
 806
 807 void strbuf_add_real_path(struct strbuf *sb, const char *path)
 808 {
 809         if (sb->len) {
 810                 struct strbuf resolved = STRBUF_INIT;
 811                 strbuf_realpath(&resolved, path, 1);
 812                 strbuf_addbuf(sb, &resolved);
 813                 strbuf_release(&resolved);
 814         } else
 815                 strbuf_realpath(sb, path, 1);
 816 }
 817
 818 int printf_ln(const char *fmt, ...)
 819 {
 820         int ret;
 821         va_list ap;
 822         va_start(ap, fmt);
 823         ret = vprintf(fmt, ap);
 824         va_end(ap);
 825         if (ret < 0 || putchar('\n') == EOF)
 826                 return -1;
 827         return ret + 1;
 828 }
 829
 830 int fprintf_ln(FILE *fp, const char *fmt, ...)
 831 {
 832         int ret;
 833         va_list ap;
 834         va_start(ap, fmt);
 835         ret = vfprintf(fp, fmt, ap);
 836         va_end(ap);
 837         if (ret < 0 || putc('\n', fp) == EOF)
 838                 return -1;
 839         return ret + 1;
 840 }
 841
 842 char *xstrdup_tolower(const char *string)
 843 {
 844         char *result;
 845         size_t len, i;
 846
 847         len = strlen(string);
 848         result = xmallocz(len);
 849         for (i = 0; i < len; i++)
 850                 result[i] = tolower(string[i]);
 851         return result;
 852 }
 853
 854 char *xstrdup_toupper(const char *string)
 855 {
 856         char *result;
 857         size_t len, i;
 858
 859         len = strlen(string);
 860         result = xmallocz(len);
 861         for (i = 0; i < len; i++)
 862                 result[i] = toupper(string[i]);
 863         return result;
 864 }
 865
 866 char *xstrvfmt(const char *fmt, va_list ap)
 867 {
 868         struct strbuf buf = STRBUF_INIT;
 869         strbuf_vaddf(&buf, fmt, ap);
 870         return strbuf_detach(&buf, NULL);
 871 }
 872
 873 char *xstrfmt(const char *fmt, ...)
 874 {
 875         va_list ap;
 876         char *ret;
 877
 878         va_start(ap, fmt);
 879         ret = xstrvfmt(fmt, ap);
 880         va_end(ap);
 881
 882         return ret;
 883 }
 884
 885 void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 886                      int tz_offset, int suppress_tz_name)
 887 {
 888         struct strbuf munged_fmt = STRBUF_INIT;
 889         size_t hint = 128;
 890         size_t len;
 891
 892         if (!*fmt)
 893                 return;
 894
 895         /*
 896          * There is no portable way to pass timezone information to
 897          * strftime, so we handle %z and %Z here.
 898          */
 899         for (;;) {
 900                 const char *percent = strchrnul(fmt, '%');
 901                 strbuf_add(&munged_fmt, fmt, percent - fmt);
 902                 if (!*percent)
 903                         break;
 904                 fmt = percent + 1;
 905                 switch (*fmt) {
 906                 case '%':
 907                         strbuf_addstr(&munged_fmt, "%%");
 908                         fmt++;
 909                         break;
 910                 case 'z':
 911                         strbuf_addf(&munged_fmt, "%+05d", tz_offset);
 912                         fmt++;
 913                         break;
 914                 case 'Z':
 915                         if (suppress_tz_name) {
 916                                 fmt++;
 917                                 break;
 918                         }
 919                         /* FALLTHROUGH */
 920                 default:
 921                         strbuf_addch(&munged_fmt, '%');
 922                 }
 923         }
 924         fmt = munged_fmt.buf;
 925
 926         strbuf_grow(sb, hint);
 927         len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
 928
 929         if (!len) {
 930                 /*
 931                  * strftime reports "0" if it could not fit the result in the buffer.
 932                  * Unfortunately, it also reports "0" if the requested time string
 933                  * takes 0 bytes. So our strategy is to munge the format so that the
 934                  * output contains at least one character, and then drop the extra
 935                  * character before returning.
 936                  */
 937                 strbuf_addch(&munged_fmt, ' ');
 938                 while (!len) {
 939                         hint *= 2;
 940                         strbuf_grow(sb, hint);
 941                         len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
 942                                        munged_fmt.buf, tm);
 943                 }
 944                 len--; /* drop munged space */
 945         }
 946         strbuf_release(&munged_fmt);
 947         strbuf_setlen(sb, sb->len + len);
 948 }
 949
 950 void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
 951                               int abbrev_len)
 952 {
 953         int r;
 954         strbuf_grow(sb, GIT_MAX_HEXSZ + 1);
 955         r = find_unique_abbrev_r(sb->buf + sb->len, oid, abbrev_len);
 956         strbuf_setlen(sb, sb->len + r);
 957 }
 958
 959 /*
 960  * Returns the length of a line, without trailing spaces.
 961  *
 962  * If the line ends with newline, it will be removed too.
 963  */
 964 static size_t cleanup(char *line, size_t len)
 965 {
 966         while (len) {
 967                 unsigned char c = line[len - 1];
 968                 if (!isspace(c))
 969                         break;
 970                 len--;
 971         }
 972
 973         return len;
 974 }
 975
 976 /*
 977  * Remove empty lines from the beginning and end
 978  * and also trailing spaces from every line.
 979  *
 980  * Turn multiple consecutive empty lines between paragraphs
 981  * into just one empty line.
 982  *
 983  * If the input has only empty lines and spaces,
 984  * no output will be produced.
 985  *
 986  * If last line does not have a newline at the end, one is added.
 987  *
 988  * Enable skip_comments to skip every line starting with comment
 989  * character.
 990  */
 991 void strbuf_stripspace(struct strbuf *sb, int skip_comments)
 992 {
 993         size_t empties = 0;
 994         size_t i, j, len, newlen;
 995         char *eol;
 996
 997         /* We may have to add a newline. */
 998         strbuf_grow(sb, 1);
 999
1000         for (i = j = 0; i < sb->len; i += len, j += newlen) {
1001                 eol = memchr(sb->buf + i, '\n', sb->len - i);
1002                 len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
1003
1004                 if (skip_comments && len && sb->buf[i] == comment_line_char) {
1005                         newlen = 0;
1006                         continue;
1007                 }
1008                 newlen = cleanup(sb->buf + i, len);
1009
1010                 /* Not just an empty line? */
1011                 if (newlen) {
1012                         if (empties > 0 && j > 0)
1013                                 sb->buf[j++] = '\n';
1014                         empties = 0;
1015                         memmove(sb->buf + j, sb->buf + i, newlen);
1016                         sb->buf[newlen + j++] = '\n';
1017                 } else {
1018                         empties++;
1019                 }
1020         }
1021
1022         strbuf_setlen(sb, j);
1023 }
1024
1025 int strbuf_normalize_path(struct strbuf *src)
1026 {
1027         struct strbuf dst = STRBUF_INIT;
1028
1029         strbuf_grow(&dst, src->len);
1030         if (normalize_path_copy(dst.buf, src->buf) < 0) {
1031                 strbuf_release(&dst);
1032                 return -1;
1033         }
1034
1035         /*
1036          * normalize_path does not tell us the new length, so we have to
1037          * compute it by looking for the new NUL it placed
1038          */
1039         strbuf_setlen(&dst, strlen(dst.buf));
1040         strbuf_swap(src, &dst);
1041         strbuf_release(&dst);
1042         return 0;
1043 }