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