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 int istarts_with(const char *str, const char *prefix)
  15 {
  16         for (; ; str++, prefix++)
  17                 if (!*prefix)
  18                         return 1;
  19                 else if (tolower(*str) != tolower(*prefix))
  20                         return 0;
  21 }
  22
  23 int skip_to_optional_arg_default(const char *str, const char *prefix,
  24                                  const char **arg, const char *def)
  25 {
  26         const char *p;
  27
  28         if (!skip_prefix(str, prefix, &p))
  29                 return 0;
  30
  31         if (!*p) {
  32                 if (arg)
  33                         *arg = def;
  34                 return 1;
  35         }
  36
  37         if (*p != '=')
  38                 return 0;
  39
  40         if (arg)
  41                 *arg = p + 1;
  42         return 1;
  43 }
  44
  45 /*
  46  * Used as the default ->buf value, so that people can always assume
  47  * buf is non NULL and ->buf is NUL terminated even for a freshly
  48  * initialized strbuf.
  49  */
  50 char strbuf_slopbuf[1];
  51
  52 void strbuf_init(struct strbuf *sb, size_t hint)
  53 {
  54         sb->alloc = sb->len = 0;
  55         sb->buf = strbuf_slopbuf;
  56         if (hint)
  57                 strbuf_grow(sb, hint);
  58 }
  59
  60 void strbuf_release(struct strbuf *sb)
  61 {
  62         if (sb->alloc) {
  63                 free(sb->buf);
  64                 strbuf_init(sb, 0);
  65         }
  66 }
  67
  68 char *strbuf_detach(struct strbuf *sb, size_t *sz)
  69 {
  70         char *res;
  71         strbuf_grow(sb, 0);
  72         res = sb->buf;
  73         if (sz)
  74                 *sz = sb->len;
  75         strbuf_init(sb, 0);
  76         return res;
  77 }
  78
  79 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  80 {
  81         strbuf_release(sb);
  82         sb->buf   = buf;
  83         sb->len   = len;
  84         sb->alloc = alloc;
  85         strbuf_grow(sb, 0);
  86         sb->buf[sb->len] = '\0';
  87 }
  88
  89 void strbuf_grow(struct strbuf *sb, size_t extra)
  90 {
  91         int new_buf = !sb->alloc;
  92         if (unsigned_add_overflows(extra, 1) ||
  93             unsigned_add_overflows(sb->len, extra + 1))
  94                 die("you want to use way too much memory");
  95         if (new_buf)
  96                 sb->buf = NULL;
  97         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  98         if (new_buf)
  99                 sb->buf[0] = '\0';
 100 }
 101
 102 void strbuf_trim(struct strbuf *sb)
 103 {
 104         strbuf_rtrim(sb);
 105         strbuf_ltrim(sb);
 106 }
 107
 108 void strbuf_rtrim(struct strbuf *sb)
 109 {
 110         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
 111                 sb->len--;
 112         sb->buf[sb->len] = '\0';
 113 }
 114
 115 void strbuf_trim_trailing_dir_sep(struct strbuf *sb)
 116 {
 117         while (sb->len > 0 && is_dir_sep((unsigned char)sb->buf[sb->len - 1]))
 118                 sb->len--;
 119         sb->buf[sb->len] = '\0';
 120 }
 121
 122 void strbuf_ltrim(struct strbuf *sb)
 123 {
 124         char *b = sb->buf;
 125         while (sb->len > 0 && isspace(*b)) {
 126                 b++;
 127                 sb->len--;
 128         }
 129         memmove(sb->buf, b, sb->len);
 130         sb->buf[sb->len] = '\0';
 131 }
 132
 133 int strbuf_reencode(struct strbuf *sb, const char *from, const char *to)
 134 {
 135         char *out;
 136         int len;
 137
 138         if (same_encoding(from, to))
 139                 return 0;
 140
 141         out = reencode_string_len(sb->buf, sb->len, to, from, &len);
 142         if (!out)
 143                 return -1;
 144
 145         strbuf_attach(sb, out, len, len);
 146         return 0;
 147 }
 148
 149 void strbuf_tolower(struct strbuf *sb)
 150 {
 151         char *p = sb->buf, *end = sb->buf + sb->len;
 152         for (; p < end; p++)
 153                 *p = tolower(*p);
 154 }
 155
 156 struct strbuf **strbuf_split_buf(const char *str, size_t slen,
 157                                  int terminator, int max)
 158 {
 159         struct strbuf **ret = NULL;
 160         size_t nr = 0, alloc = 0;
 161         struct strbuf *t;
 162
 163         while (slen) {
 164                 int len = slen;
 165                 if (max <= 0 || nr + 1 < max) {
 166                         const char *end = memchr(str, terminator, slen);
 167                         if (end)
 168                                 len = end - str + 1;
 169                 }
 170                 t = xmalloc(sizeof(struct strbuf));
 171                 strbuf_init(t, len);
 172                 strbuf_add(t, str, len);
 173                 ALLOC_GROW(ret, nr + 2, alloc);
 174                 ret[nr++] = t;
 175                 str += len;
 176                 slen -= len;
 177         }
 178         ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 179         ret[nr] = NULL;
 180         return ret;
 181 }
 182
 183 void strbuf_list_free(struct strbuf **sbs)
 184 {
 185         struct strbuf **s = sbs;
 186
 187         while (*s) {
 188                 strbuf_release(*s);
 189                 free(*s++);
 190         }
 191         free(sbs);
 192 }
 193
 194 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 195 {
 196         int len = a->len < b->len ? a->len: b->len;
 197         int cmp = memcmp(a->buf, b->buf, len);
 198         if (cmp)
 199                 return cmp;
 200         return a->len < b->len ? -1: a->len != b->len;
 201 }
 202
 203 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 204                                    const void *data, size_t dlen)
 205 {
 206         if (unsigned_add_overflows(pos, len))
 207                 die("you want to use way too much memory");
 208         if (pos > sb->len)
 209                 die("`pos' is too far after the end of the buffer");
 210         if (pos + len > sb->len)
 211                 die("`pos + len' is too far after the end of the buffer");
 212
 213         if (dlen >= len)
 214                 strbuf_grow(sb, dlen - len);
 215         memmove(sb->buf + pos + dlen,
 216                         sb->buf + pos + len,
 217                         sb->len - pos - len);
 218         memcpy(sb->buf + pos, data, dlen);
 219         strbuf_setlen(sb, sb->len + dlen - len);
 220 }
 221
 222 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 223 {
 224         strbuf_splice(sb, pos, 0, data, len);
 225 }
 226
 227 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 228 {
 229         strbuf_splice(sb, pos, len, "", 0);
 230 }
 231
 232 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 233 {
 234         strbuf_grow(sb, len);
 235         memcpy(sb->buf + sb->len, data, len);
 236         strbuf_setlen(sb, sb->len + len);
 237 }
 238
 239 void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
 240 {
 241         strbuf_grow(sb, sb2->len);
 242         memcpy(sb->buf + sb->len, sb2->buf, sb2->len);
 243         strbuf_setlen(sb, sb->len + sb2->len);
 244 }
 245
 246 void strbuf_addchars(struct strbuf *sb, int c, size_t n)
 247 {
 248         strbuf_grow(sb, n);
 249         memset(sb->buf + sb->len, c, n);
 250         strbuf_setlen(sb, sb->len + n);
 251 }
 252
 253 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 254 {
 255         va_list ap;
 256         va_start(ap, fmt);
 257         strbuf_vaddf(sb, fmt, ap);
 258         va_end(ap);
 259 }
 260
 261 static void add_lines(struct strbuf *out,
 262                         const char *prefix1,
 263                         const char *prefix2,
 264                         const char *buf, size_t size)
 265 {
 266         while (size) {
 267                 const char *prefix;
 268                 const char *next = memchr(buf, '\n', size);
 269                 next = next ? (next + 1) : (buf + size);
 270
 271                 prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
 272                           ? prefix2 : prefix1);
 273                 strbuf_addstr(out, prefix);
 274                 strbuf_add(out, buf, next - buf);
 275                 size -= next - buf;
 276                 buf = next;
 277         }
 278         strbuf_complete_line(out);
 279 }
 280
 281 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 282 {
 283         static char prefix1[3];
 284         static char prefix2[2];
 285
 286         if (prefix1[0] != comment_line_char) {
 287                 xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
 288                 xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
 289         }
 290         add_lines(out, prefix1, prefix2, buf, size);
 291 }
 292
 293 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 294 {
 295         va_list params;
 296         struct strbuf buf = STRBUF_INIT;
 297         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 298
 299         va_start(params, fmt);
 300         strbuf_vaddf(&buf, fmt, params);
 301         va_end(params);
 302
 303         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 304         if (incomplete_line)
 305                 sb->buf[--sb->len] = '\0';
 306
 307         strbuf_release(&buf);
 308 }
 309
 310 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 311 {
 312         int len;
 313         va_list cp;
 314
 315         if (!strbuf_avail(sb))
 316                 strbuf_grow(sb, 64);
 317         va_copy(cp, ap);
 318         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 319         va_end(cp);
 320         if (len < 0)
 321                 die("BUG: your vsnprintf is broken (returned %d)", len);
 322         if (len > strbuf_avail(sb)) {
 323                 strbuf_grow(sb, len);
 324                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 325                 if (len > strbuf_avail(sb))
 326                         die("BUG: your vsnprintf is broken (insatiable)");
 327         }
 328         strbuf_setlen(sb, sb->len + len);
 329 }
 330
 331 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 332                    void *context)
 333 {
 334         for (;;) {
 335                 const char *percent;
 336                 size_t consumed;
 337
 338                 percent = strchrnul(format, '%');
 339                 strbuf_add(sb, format, percent - format);
 340                 if (!*percent)
 341                         break;
 342                 format = percent + 1;
 343
 344                 if (*format == '%') {
 345                         strbuf_addch(sb, '%');
 346                         format++;
 347                         continue;
 348                 }
 349
 350                 consumed = fn(sb, format, context);
 351                 if (consumed)
 352                         format += consumed;
 353                 else
 354                         strbuf_addch(sb, '%');
 355         }
 356 }
 357
 358 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 359                 void *context)
 360 {
 361         struct strbuf_expand_dict_entry *e = context;
 362         size_t len;
 363
 364         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 365                 if (!strncmp(placeholder, e->placeholder, len)) {
 366                         if (e->value)
 367                                 strbuf_addstr(sb, e->value);
 368                         return len;
 369                 }
 370         }
 371         return 0;
 372 }
 373
 374 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 375 {
 376         int i, len = src->len;
 377
 378         for (i = 0; i < len; i++) {
 379                 if (src->buf[i] == '%')
 380                         strbuf_addch(dst, '%');
 381                 strbuf_addch(dst, src->buf[i]);
 382         }
 383 }
 384
 385 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 386 {
 387         size_t res;
 388         size_t oldalloc = sb->alloc;
 389
 390         strbuf_grow(sb, size);
 391         res = fread(sb->buf + sb->len, 1, size, f);
 392         if (res > 0)
 393                 strbuf_setlen(sb, sb->len + res);
 394         else if (oldalloc == 0)
 395                 strbuf_release(sb);
 396         return res;
 397 }
 398
 399 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 400 {
 401         size_t oldlen = sb->len;
 402         size_t oldalloc = sb->alloc;
 403
 404         strbuf_grow(sb, hint ? hint : 8192);
 405         for (;;) {
 406                 ssize_t want = sb->alloc - sb->len - 1;
 407                 ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
 408
 409                 if (got < 0) {
 410                         if (oldalloc == 0)
 411                                 strbuf_release(sb);
 412                         else
 413                                 strbuf_setlen(sb, oldlen);
 414                         return -1;
 415                 }
 416                 sb->len += got;
 417                 if (got < want)
 418                         break;
 419                 strbuf_grow(sb, 8192);
 420         }
 421
 422         sb->buf[sb->len] = '\0';
 423         return sb->len - oldlen;
 424 }
 425
 426 ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
 427 {
 428         size_t oldalloc = sb->alloc;
 429         ssize_t cnt;
 430
 431         strbuf_grow(sb, hint ? hint : 8192);
 432         cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 433         if (cnt > 0)
 434                 strbuf_setlen(sb, sb->len + cnt);
 435         else if (oldalloc == 0)
 436                 strbuf_release(sb);
 437         return cnt;
 438 }
 439
 440 ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 441 {
 442         return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 443 }
 444
 445
 446 #define STRBUF_MAXLINK (2*PATH_MAX)
 447
 448 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 449 {
 450         size_t oldalloc = sb->alloc;
 451
 452         if (hint < 32)
 453                 hint = 32;
 454
 455         while (hint < STRBUF_MAXLINK) {
 456                 int len;
 457
 458                 strbuf_grow(sb, hint);
 459                 len = readlink(path, sb->buf, hint);
 460                 if (len < 0) {
 461                         if (errno != ERANGE)
 462                                 break;
 463                 } else if (len < hint) {
 464                         strbuf_setlen(sb, len);
 465                         return 0;
 466                 }
 467
 468                 /* .. the buffer was too small - try again */
 469                 hint *= 2;
 470         }
 471         if (oldalloc == 0)
 472                 strbuf_release(sb);
 473         return -1;
 474 }
 475
 476 int strbuf_getcwd(struct strbuf *sb)
 477 {
 478         size_t oldalloc = sb->alloc;
 479         size_t guessed_len = 128;
 480
 481         for (;; guessed_len *= 2) {
 482                 strbuf_grow(sb, guessed_len);
 483                 if (getcwd(sb->buf, sb->alloc)) {
 484                         strbuf_setlen(sb, strlen(sb->buf));
 485                         return 0;
 486                 }
 487
 488                 /*
 489                  * If getcwd(3) is implemented as a syscall that falls
 490                  * back to a regular lookup using readdir(3) etc. then
 491                  * we may be able to avoid EACCES by providing enough
 492                  * space to the syscall as it's not necessarily bound
 493                  * to the same restrictions as the fallback.
 494                  */
 495                 if (errno == EACCES && guessed_len < PATH_MAX)
 496                         continue;
 497
 498                 if (errno != ERANGE)
 499                         break;
 500         }
 501         if (oldalloc == 0)
 502                 strbuf_release(sb);
 503         else
 504                 strbuf_reset(sb);
 505         return -1;
 506 }
 507
 508 #ifdef HAVE_GETDELIM
 509 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 510 {
 511         ssize_t r;
 512
 513         if (feof(fp))
 514                 return EOF;
 515
 516         strbuf_reset(sb);
 517
 518         /* Translate slopbuf to NULL, as we cannot call realloc on it */
 519         if (!sb->alloc)
 520                 sb->buf = NULL;
 521         errno = 0;
 522         r = getdelim(&sb->buf, &sb->alloc, term, fp);
 523
 524         if (r > 0) {
 525                 sb->len = r;
 526                 return 0;
 527         }
 528         assert(r == -1);
 529
 530         /*
 531          * Normally we would have called xrealloc, which will try to free
 532          * memory and recover. But we have no way to tell getdelim() to do so.
 533          * Worse, we cannot try to recover ENOMEM ourselves, because we have
 534          * no idea how many bytes were read by getdelim.
 535          *
 536          * Dying here is reasonable. It mirrors what xrealloc would do on
 537          * catastrophic memory failure. We skip the opportunity to free pack
 538          * memory and retry, but that's unlikely to help for a malloc small
 539          * enough to hold a single line of input, anyway.
 540          */
 541         if (errno == ENOMEM)
 542                 die("Out of memory, getdelim failed");
 543
 544         /*
 545          * Restore strbuf invariants; if getdelim left us with a NULL pointer,
 546          * we can just re-init, but otherwise we should make sure that our
 547          * length is empty, and that the result is NUL-terminated.
 548          */
 549         if (!sb->buf)
 550                 strbuf_init(sb, 0);
 551         else
 552                 strbuf_reset(sb);
 553         return EOF;
 554 }
 555 #else
 556 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 557 {
 558         int ch;
 559
 560         if (feof(fp))
 561                 return EOF;
 562
 563         strbuf_reset(sb);
 564         flockfile(fp);
 565         while ((ch = getc_unlocked(fp)) != EOF) {
 566                 if (!strbuf_avail(sb))
 567                         strbuf_grow(sb, 1);
 568                 sb->buf[sb->len++] = ch;
 569                 if (ch == term)
 570                         break;
 571         }
 572         funlockfile(fp);
 573         if (ch == EOF && sb->len == 0)
 574                 return EOF;
 575
 576         sb->buf[sb->len] = '\0';
 577         return 0;
 578 }
 579 #endif
 580
 581 static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 582 {
 583         if (strbuf_getwholeline(sb, fp, term))
 584                 return EOF;
 585         if (sb->buf[sb->len - 1] == term)
 586                 strbuf_setlen(sb, sb->len - 1);
 587         return 0;
 588 }
 589
 590 int strbuf_getline(struct strbuf *sb, FILE *fp)
 591 {
 592         if (strbuf_getwholeline(sb, fp, '\n'))
 593                 return EOF;
 594         if (sb->buf[sb->len - 1] == '\n') {
 595                 strbuf_setlen(sb, sb->len - 1);
 596                 if (sb->len && sb->buf[sb->len - 1] == '\r')
 597                         strbuf_setlen(sb, sb->len - 1);
 598         }
 599         return 0;
 600 }
 601
 602 int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 603 {
 604         return strbuf_getdelim(sb, fp, '\n');
 605 }
 606
 607 int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 608 {
 609         return strbuf_getdelim(sb, fp, '\0');
 610 }
 611
 612 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 613 {
 614         strbuf_reset(sb);
 615
 616         while (1) {
 617                 char ch;
 618                 ssize_t len = xread(fd, &ch, 1);
 619                 if (len <= 0)
 620                         return EOF;
 621                 strbuf_addch(sb, ch);
 622                 if (ch == term)
 623                         break;
 624         }
 625         return 0;
 626 }
 627
 628 ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 629 {
 630         int fd;
 631         ssize_t len;
 632         int saved_errno;
 633
 634         fd = open(path, O_RDONLY);
 635         if (fd < 0)
 636                 return -1;
 637         len = strbuf_read(sb, fd, hint);
 638         saved_errno = errno;
 639         close(fd);
 640         if (len < 0) {
 641                 errno = saved_errno;
 642                 return -1;
 643         }
 644
 645         return len;
 646 }
 647
 648 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 649                       const char *buf, size_t size)
 650 {
 651         add_lines(out, prefix, NULL, buf, size);
 652 }
 653
 654 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 655 {
 656         while (*s) {
 657                 size_t len = strcspn(s, "\"<>&");
 658                 strbuf_add(buf, s, len);
 659                 s += len;
 660                 switch (*s) {
 661                 case '"':
 662                         strbuf_addstr(buf, "&quot;");
 663                         break;
 664                 case '<':
 665                         strbuf_addstr(buf, "&lt;");
 666                         break;
 667                 case '>':
 668                         strbuf_addstr(buf, "&gt;");
 669                         break;
 670                 case '&':
 671                         strbuf_addstr(buf, "&amp;");
 672                         break;
 673                 case 0:
 674                         return;
 675                 }
 676                 s++;
 677         }
 678 }
 679
 680 static int is_rfc3986_reserved(char ch)
 681 {
 682         switch (ch) {
 683                 case '!': case '*': case '\'': case '(': case ')': case ';':
 684                 case ':': case '@': case '&': case '=': case '+': case '$':
 685                 case ',': case '/': case '?': case '#': case '[': case ']':
 686                         return 1;
 687         }
 688         return 0;
 689 }
 690
 691 static int is_rfc3986_unreserved(char ch)
 692 {
 693         return isalnum(ch) ||
 694                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 695 }
 696
 697 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 698                                  int reserved)
 699 {
 700         strbuf_grow(sb, len);
 701         while (len--) {
 702                 char ch = *s++;
 703                 if (is_rfc3986_unreserved(ch) ||
 704                     (!reserved && is_rfc3986_reserved(ch)))
 705                         strbuf_addch(sb, ch);
 706                 else
 707                         strbuf_addf(sb, "%%%02x", (unsigned char)ch);
 708         }
 709 }
 710
 711 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 712                              int reserved)
 713 {
 714         strbuf_add_urlencode(sb, s, strlen(s), reserved);
 715 }
 716
 717 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 718 {
 719         if (bytes > 1 << 30) {
 720                 strbuf_addf(buf, "%u.%2.2u GiB",
 721                             (int)(bytes >> 30),
 722                             (int)(bytes & ((1 << 30) - 1)) / 10737419);
 723         } else if (bytes > 1 << 20) {
 724                 int x = bytes + 5243;  /* for rounding */
 725                 strbuf_addf(buf, "%u.%2.2u MiB",
 726                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 727         } else if (bytes > 1 << 10) {
 728                 int x = bytes + 5;  /* for rounding */
 729                 strbuf_addf(buf, "%u.%2.2u KiB",
 730                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 731         } else {
 732                 strbuf_addf(buf, "%u bytes", (int)bytes);
 733         }
 734 }
 735
 736 void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 737 {
 738         if (!*path)
 739                 die("The empty string is not a valid path");
 740         if (!is_absolute_path(path)) {
 741                 struct stat cwd_stat, pwd_stat;
 742                 size_t orig_len = sb->len;
 743                 char *cwd = xgetcwd();
 744                 char *pwd = getenv("PWD");
 745                 if (pwd && strcmp(pwd, cwd) &&
 746                     !stat(cwd, &cwd_stat) &&
 747                     (cwd_stat.st_dev || cwd_stat.st_ino) &&
 748                     !stat(pwd, &pwd_stat) &&
 749                     pwd_stat.st_dev == cwd_stat.st_dev &&
 750                     pwd_stat.st_ino == cwd_stat.st_ino)
 751                         strbuf_addstr(sb, pwd);
 752                 else
 753                         strbuf_addstr(sb, cwd);
 754                 if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 755                         strbuf_addch(sb, '/');
 756                 free(cwd);
 757         }
 758         strbuf_addstr(sb, path);
 759 }
 760
 761 void strbuf_add_real_path(struct strbuf *sb, const char *path)
 762 {
 763         if (sb->len) {
 764                 struct strbuf resolved = STRBUF_INIT;
 765                 strbuf_realpath(&resolved, path, 1);
 766                 strbuf_addbuf(sb, &resolved);
 767                 strbuf_release(&resolved);
 768         } else
 769                 strbuf_realpath(sb, path, 1);
 770 }
 771
 772 int printf_ln(const char *fmt, ...)
 773 {
 774         int ret;
 775         va_list ap;
 776         va_start(ap, fmt);
 777         ret = vprintf(fmt, ap);
 778         va_end(ap);
 779         if (ret < 0 || putchar('\n') == EOF)
 780                 return -1;
 781         return ret + 1;
 782 }
 783
 784 int fprintf_ln(FILE *fp, const char *fmt, ...)
 785 {
 786         int ret;
 787         va_list ap;
 788         va_start(ap, fmt);
 789         ret = vfprintf(fp, fmt, ap);
 790         va_end(ap);
 791         if (ret < 0 || putc('\n', fp) == EOF)
 792                 return -1;
 793         return ret + 1;
 794 }
 795
 796 char *xstrdup_tolower(const char *string)
 797 {
 798         char *result;
 799         size_t len, i;
 800
 801         len = strlen(string);
 802         result = xmallocz(len);
 803         for (i = 0; i < len; i++)
 804                 result[i] = tolower(string[i]);
 805         return result;
 806 }
 807
 808 char *xstrdup_toupper(const char *string)
 809 {
 810         char *result;
 811         size_t len, i;
 812
 813         len = strlen(string);
 814         result = xmallocz(len);
 815         for (i = 0; i < len; i++)
 816                 result[i] = toupper(string[i]);
 817         return result;
 818 }
 819
 820 char *xstrvfmt(const char *fmt, va_list ap)
 821 {
 822         struct strbuf buf = STRBUF_INIT;
 823         strbuf_vaddf(&buf, fmt, ap);
 824         return strbuf_detach(&buf, NULL);
 825 }
 826
 827 char *xstrfmt(const char *fmt, ...)
 828 {
 829         va_list ap;
 830         char *ret;
 831
 832         va_start(ap, fmt);
 833         ret = xstrvfmt(fmt, ap);
 834         va_end(ap);
 835
 836         return ret;
 837 }
 838
 839 void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 840                      int tz_offset, int suppress_tz_name)
 841 {
 842         struct strbuf munged_fmt = STRBUF_INIT;
 843         size_t hint = 128;
 844         size_t len;
 845
 846         if (!*fmt)
 847                 return;
 848
 849         /*
 850          * There is no portable way to pass timezone information to
 851          * strftime, so we handle %z and %Z here.
 852          */
 853         for (;;) {
 854                 const char *percent = strchrnul(fmt, '%');
 855                 strbuf_add(&munged_fmt, fmt, percent - fmt);
 856                 if (!*percent)
 857                         break;
 858                 fmt = percent + 1;
 859                 switch (*fmt) {
 860                 case '%':
 861                         strbuf_addstr(&munged_fmt, "%%");
 862                         fmt++;
 863                         break;
 864                 case 'z':
 865                         strbuf_addf(&munged_fmt, "%+05d", tz_offset);
 866                         fmt++;
 867                         break;
 868                 case 'Z':
 869                         if (suppress_tz_name) {
 870                                 fmt++;
 871                                 break;
 872                         }
 873                         /* FALLTHROUGH */
 874                 default:
 875                         strbuf_addch(&munged_fmt, '%');
 876                 }
 877         }
 878         fmt = munged_fmt.buf;
 879
 880         strbuf_grow(sb, hint);
 881         len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
 882
 883         if (!len) {
 884                 /*
 885                  * strftime reports "0" if it could not fit the result in the buffer.
 886                  * Unfortunately, it also reports "0" if the requested time string
 887                  * takes 0 bytes. So our strategy is to munge the format so that the
 888                  * output contains at least one character, and then drop the extra
 889                  * character before returning.
 890                  */
 891                 strbuf_addch(&munged_fmt, ' ');
 892                 while (!len) {
 893                         hint *= 2;
 894                         strbuf_grow(sb, hint);
 895                         len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
 896                                        munged_fmt.buf, tm);
 897                 }
 898                 len--; /* drop munged space */
 899         }
 900         strbuf_release(&munged_fmt);
 901         strbuf_setlen(sb, sb->len + len);
 902 }
 903
 904 void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
 905                               int abbrev_len)
 906 {
 907         int r;
 908         strbuf_grow(sb, GIT_SHA1_HEXSZ + 1);
 909         r = find_unique_abbrev_r(sb->buf + sb->len, oid, abbrev_len);
 910         strbuf_setlen(sb, sb->len + r);
 911 }
 912
 913 /*
 914  * Returns the length of a line, without trailing spaces.
 915  *
 916  * If the line ends with newline, it will be removed too.
 917  */
 918 static size_t cleanup(char *line, size_t len)
 919 {
 920         while (len) {
 921                 unsigned char c = line[len - 1];
 922                 if (!isspace(c))
 923                         break;
 924                 len--;
 925         }
 926
 927         return len;
 928 }
 929
 930 /*
 931  * Remove empty lines from the beginning and end
 932  * and also trailing spaces from every line.
 933  *
 934  * Turn multiple consecutive empty lines between paragraphs
 935  * into just one empty line.
 936  *
 937  * If the input has only empty lines and spaces,
 938  * no output will be produced.
 939  *
 940  * If last line does not have a newline at the end, one is added.
 941  *
 942  * Enable skip_comments to skip every line starting with comment
 943  * character.
 944  */
 945 void strbuf_stripspace(struct strbuf *sb, int skip_comments)
 946 {
 947         int empties = 0;
 948         size_t i, j, len, newlen;
 949         char *eol;
 950
 951         /* We may have to add a newline. */
 952         strbuf_grow(sb, 1);
 953
 954         for (i = j = 0; i < sb->len; i += len, j += newlen) {
 955                 eol = memchr(sb->buf + i, '\n', sb->len - i);
 956                 len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
 957
 958                 if (skip_comments && len && sb->buf[i] == comment_line_char) {
 959                         newlen = 0;
 960                         continue;
 961                 }
 962                 newlen = cleanup(sb->buf + i, len);
 963
 964                 /* Not just an empty line? */
 965                 if (newlen) {
 966                         if (empties > 0 && j > 0)
 967                                 sb->buf[j++] = '\n';
 968                         empties = 0;
 969                         memmove(sb->buf + j, sb->buf + i, newlen);
 970                         sb->buf[newlen + j++] = '\n';
 971                 } else {
 972                         empties++;
 973                 }
 974         }
 975
 976         strbuf_setlen(sb, j);
 977 }
 978
 979 int strbuf_normalize_path(struct strbuf *src)
 980 {
 981         struct strbuf dst = STRBUF_INIT;
 982
 983         strbuf_grow(&dst, src->len);
 984         if (normalize_path_copy(dst.buf, src->buf) < 0) {
 985                 strbuf_release(&dst);
 986                 return -1;
 987         }
 988
 989         /*
 990          * normalize_path does not tell us the new length, so we have to
 991          * compute it by looking for the new NUL it placed
 992          */
 993         strbuf_setlen(&dst, strlen(dst.buf));
 994         strbuf_swap(src, &dst);
 995         strbuf_release(&dst);
 996         return 0;
 997 }