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         struct strbuf blank = STRBUF_INIT;
  56         memcpy(sb, &blank, sizeof(*sb));
  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         if (!s)
 213                 return;
 214         while (*s) {
 215                 strbuf_release(*s);
 216                 free(*s++);
 217         }
 218         free(sbs);
 219 }
 220
 221 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 222 {
 223         size_t len = a->len < b->len ? a->len: b->len;
 224         int cmp = memcmp(a->buf, b->buf, len);
 225         if (cmp)
 226                 return cmp;
 227         return a->len < b->len ? -1: a->len != b->len;
 228 }
 229
 230 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 231                                    const void *data, size_t dlen)
 232 {
 233         if (unsigned_add_overflows(pos, len))
 234                 die("you want to use way too much memory");
 235         if (pos > sb->len)
 236                 die("`pos' is too far after the end of the buffer");
 237         if (pos + len > sb->len)
 238                 die("`pos + len' is too far after the end of the buffer");
 239
 240         if (dlen >= len)
 241                 strbuf_grow(sb, dlen - len);
 242         memmove(sb->buf + pos + dlen,
 243                         sb->buf + pos + len,
 244                         sb->len - pos - len);
 245         memcpy(sb->buf + pos, data, dlen);
 246         strbuf_setlen(sb, sb->len + dlen - len);
 247 }
 248
 249 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 250 {
 251         strbuf_splice(sb, pos, 0, data, len);
 252 }
 253
 254 void strbuf_vinsertf(struct strbuf *sb, size_t pos, const char *fmt, va_list ap)
 255 {
 256         int len, len2;
 257         char save;
 258         va_list cp;
 259
 260         if (pos > sb->len)
 261                 die("`pos' is too far after the end of the buffer");
 262         va_copy(cp, ap);
 263         len = vsnprintf(sb->buf + sb->len, 0, fmt, cp);
 264         va_end(cp);
 265         if (len < 0)
 266                 BUG("your vsnprintf is broken (returned %d)", len);
 267         if (!len)
 268                 return; /* nothing to do */
 269         if (unsigned_add_overflows(sb->len, len))
 270                 die("you want to use way too much memory");
 271         strbuf_grow(sb, len);
 272         memmove(sb->buf + pos + len, sb->buf + pos, sb->len - pos);
 273         /* vsnprintf() will append a NUL, overwriting one of our characters */
 274         save = sb->buf[pos + len];
 275         len2 = vsnprintf(sb->buf + pos, len + 1, fmt, ap);
 276         sb->buf[pos + len] = save;
 277         if (len2 != len)
 278                 BUG("your vsnprintf is broken (returns inconsistent lengths)");
 279         strbuf_setlen(sb, sb->len + len);
 280 }
 281
 282 void strbuf_insertf(struct strbuf *sb, size_t pos, const char *fmt, ...)
 283 {
 284         va_list ap;
 285         va_start(ap, fmt);
 286         strbuf_vinsertf(sb, pos, fmt, ap);
 287         va_end(ap);
 288 }
 289
 290 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 291 {
 292         strbuf_splice(sb, pos, len, "", 0);
 293 }
 294
 295 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 296 {
 297         strbuf_grow(sb, len);
 298         memcpy(sb->buf + sb->len, data, len);
 299         strbuf_setlen(sb, sb->len + len);
 300 }
 301
 302 void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
 303 {
 304         strbuf_grow(sb, sb2->len);
 305         memcpy(sb->buf + sb->len, sb2->buf, sb2->len);
 306         strbuf_setlen(sb, sb->len + sb2->len);
 307 }
 308
 309 const char *strbuf_join_argv(struct strbuf *buf,
 310                              int argc, const char **argv, char delim)
 311 {
 312         if (!argc)
 313                 return buf->buf;
 314
 315         strbuf_addstr(buf, *argv);
 316         while (--argc) {
 317                 strbuf_addch(buf, delim);
 318                 strbuf_addstr(buf, *(++argv));
 319         }
 320
 321         return buf->buf;
 322 }
 323
 324 void strbuf_addchars(struct strbuf *sb, int c, size_t n)
 325 {
 326         strbuf_grow(sb, n);
 327         memset(sb->buf + sb->len, c, n);
 328         strbuf_setlen(sb, sb->len + n);
 329 }
 330
 331 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 332 {
 333         va_list ap;
 334         va_start(ap, fmt);
 335         strbuf_vaddf(sb, fmt, ap);
 336         va_end(ap);
 337 }
 338
 339 static void add_lines(struct strbuf *out,
 340                         const char *prefix1,
 341                         const char *prefix2,
 342                         const char *buf, size_t size)
 343 {
 344         while (size) {
 345                 const char *prefix;
 346                 const char *next = memchr(buf, '\n', size);
 347                 next = next ? (next + 1) : (buf + size);
 348
 349                 prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
 350                           ? prefix2 : prefix1);
 351                 strbuf_addstr(out, prefix);
 352                 strbuf_add(out, buf, next - buf);
 353                 size -= next - buf;
 354                 buf = next;
 355         }
 356         strbuf_complete_line(out);
 357 }
 358
 359 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 360 {
 361         static char prefix1[3];
 362         static char prefix2[2];
 363
 364         if (prefix1[0] != comment_line_char) {
 365                 xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
 366                 xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
 367         }
 368         add_lines(out, prefix1, prefix2, buf, size);
 369 }
 370
 371 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 372 {
 373         va_list params;
 374         struct strbuf buf = STRBUF_INIT;
 375         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 376
 377         va_start(params, fmt);
 378         strbuf_vaddf(&buf, fmt, params);
 379         va_end(params);
 380
 381         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 382         if (incomplete_line)
 383                 sb->buf[--sb->len] = '\0';
 384
 385         strbuf_release(&buf);
 386 }
 387
 388 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 389 {
 390         int len;
 391         va_list cp;
 392
 393         if (!strbuf_avail(sb))
 394                 strbuf_grow(sb, 64);
 395         va_copy(cp, ap);
 396         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 397         va_end(cp);
 398         if (len < 0)
 399                 BUG("your vsnprintf is broken (returned %d)", len);
 400         if (len > strbuf_avail(sb)) {
 401                 strbuf_grow(sb, len);
 402                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 403                 if (len > strbuf_avail(sb))
 404                         BUG("your vsnprintf is broken (insatiable)");
 405         }
 406         strbuf_setlen(sb, sb->len + len);
 407 }
 408
 409 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 410                    void *context)
 411 {
 412         for (;;) {
 413                 const char *percent;
 414                 size_t consumed;
 415
 416                 percent = strchrnul(format, '%');
 417                 strbuf_add(sb, format, percent - format);
 418                 if (!*percent)
 419                         break;
 420                 format = percent + 1;
 421
 422                 if (*format == '%') {
 423                         strbuf_addch(sb, '%');
 424                         format++;
 425                         continue;
 426                 }
 427
 428                 consumed = fn(sb, format, context);
 429                 if (consumed)
 430                         format += consumed;
 431                 else
 432                         strbuf_addch(sb, '%');
 433         }
 434 }
 435
 436 size_t strbuf_expand_literal_cb(struct strbuf *sb,
 437                                 const char *placeholder,
 438                                 void *context)
 439 {
 440         int ch;
 441
 442         switch (placeholder[0]) {
 443         case 'n':               /* newline */
 444                 strbuf_addch(sb, '\n');
 445                 return 1;
 446         case 'x':
 447                 /* %x00 == NUL, %x0a == LF, etc. */
 448                 ch = hex2chr(placeholder + 1);
 449                 if (ch < 0)
 450                         return 0;
 451                 strbuf_addch(sb, ch);
 452                 return 3;
 453         }
 454         return 0;
 455 }
 456
 457 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 458                 void *context)
 459 {
 460         struct strbuf_expand_dict_entry *e = context;
 461         size_t len;
 462
 463         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 464                 if (!strncmp(placeholder, e->placeholder, len)) {
 465                         if (e->value)
 466                                 strbuf_addstr(sb, e->value);
 467                         return len;
 468                 }
 469         }
 470         return 0;
 471 }
 472
 473 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 474 {
 475         size_t i, len = src->len;
 476
 477         for (i = 0; i < len; i++) {
 478                 if (src->buf[i] == '%')
 479                         strbuf_addch(dst, '%');
 480                 strbuf_addch(dst, src->buf[i]);
 481         }
 482 }
 483
 484 #define URL_UNSAFE_CHARS " <>\"%{}|\\^`:?#[]@!$&'()*+,;="
 485
 486 void strbuf_add_percentencode(struct strbuf *dst, const char *src, int flags)
 487 {
 488         size_t i, len = strlen(src);
 489
 490         for (i = 0; i < len; i++) {
 491                 unsigned char ch = src[i];
 492                 if (ch <= 0x1F || ch >= 0x7F ||
 493                     (ch == '/' && (flags & STRBUF_ENCODE_SLASH)) ||
 494                     strchr(URL_UNSAFE_CHARS, ch))
 495                         strbuf_addf(dst, "%%%02X", (unsigned char)ch);
 496                 else
 497                         strbuf_addch(dst, ch);
 498         }
 499 }
 500
 501 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 502 {
 503         size_t res;
 504         size_t oldalloc = sb->alloc;
 505
 506         strbuf_grow(sb, size);
 507         res = fread(sb->buf + sb->len, 1, size, f);
 508         if (res > 0)
 509                 strbuf_setlen(sb, sb->len + res);
 510         else if (oldalloc == 0)
 511                 strbuf_release(sb);
 512         return res;
 513 }
 514
 515 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 516 {
 517         size_t oldlen = sb->len;
 518         size_t oldalloc = sb->alloc;
 519
 520         strbuf_grow(sb, hint ? hint : 8192);
 521         for (;;) {
 522                 ssize_t want = sb->alloc - sb->len - 1;
 523                 ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
 524
 525                 if (got < 0) {
 526                         if (oldalloc == 0)
 527                                 strbuf_release(sb);
 528                         else
 529                                 strbuf_setlen(sb, oldlen);
 530                         return -1;
 531                 }
 532                 sb->len += got;
 533                 if (got < want)
 534                         break;
 535                 strbuf_grow(sb, 8192);
 536         }
 537
 538         sb->buf[sb->len] = '\0';
 539         return sb->len - oldlen;
 540 }
 541
 542 ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
 543 {
 544         size_t oldalloc = sb->alloc;
 545         ssize_t cnt;
 546
 547         strbuf_grow(sb, hint ? hint : 8192);
 548         cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 549         if (cnt > 0)
 550                 strbuf_setlen(sb, sb->len + cnt);
 551         else if (oldalloc == 0)
 552                 strbuf_release(sb);
 553         return cnt;
 554 }
 555
 556 ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 557 {
 558         return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 559 }
 560
 561 #define STRBUF_MAXLINK (2*PATH_MAX)
 562
 563 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 564 {
 565         size_t oldalloc = sb->alloc;
 566
 567         if (hint < 32)
 568                 hint = 32;
 569
 570         while (hint < STRBUF_MAXLINK) {
 571                 ssize_t len;
 572
 573                 strbuf_grow(sb, hint);
 574                 len = readlink(path, sb->buf, hint);
 575                 if (len < 0) {
 576                         if (errno != ERANGE)
 577                                 break;
 578                 } else if (len < hint) {
 579                         strbuf_setlen(sb, len);
 580                         return 0;
 581                 }
 582
 583                 /* .. the buffer was too small - try again */
 584                 hint *= 2;
 585         }
 586         if (oldalloc == 0)
 587                 strbuf_release(sb);
 588         return -1;
 589 }
 590
 591 int strbuf_getcwd(struct strbuf *sb)
 592 {
 593         size_t oldalloc = sb->alloc;
 594         size_t guessed_len = 128;
 595
 596         for (;; guessed_len *= 2) {
 597                 strbuf_grow(sb, guessed_len);
 598                 if (getcwd(sb->buf, sb->alloc)) {
 599                         strbuf_setlen(sb, strlen(sb->buf));
 600                         return 0;
 601                 }
 602
 603                 /*
 604                  * If getcwd(3) is implemented as a syscall that falls
 605                  * back to a regular lookup using readdir(3) etc. then
 606                  * we may be able to avoid EACCES by providing enough
 607                  * space to the syscall as it's not necessarily bound
 608                  * to the same restrictions as the fallback.
 609                  */
 610                 if (errno == EACCES && guessed_len < PATH_MAX)
 611                         continue;
 612
 613                 if (errno != ERANGE)
 614                         break;
 615         }
 616         if (oldalloc == 0)
 617                 strbuf_release(sb);
 618         else
 619                 strbuf_reset(sb);
 620         return -1;
 621 }
 622
 623 #ifdef HAVE_GETDELIM
 624 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 625 {
 626         ssize_t r;
 627
 628         if (feof(fp))
 629                 return EOF;
 630
 631         strbuf_reset(sb);
 632
 633         /* Translate slopbuf to NULL, as we cannot call realloc on it */
 634         if (!sb->alloc)
 635                 sb->buf = NULL;
 636         errno = 0;
 637         r = getdelim(&sb->buf, &sb->alloc, term, fp);
 638
 639         if (r > 0) {
 640                 sb->len = r;
 641                 return 0;
 642         }
 643         assert(r == -1);
 644
 645         /*
 646          * Normally we would have called xrealloc, which will try to free
 647          * memory and recover. But we have no way to tell getdelim() to do so.
 648          * Worse, we cannot try to recover ENOMEM ourselves, because we have
 649          * no idea how many bytes were read by getdelim.
 650          *
 651          * Dying here is reasonable. It mirrors what xrealloc would do on
 652          * catastrophic memory failure. We skip the opportunity to free pack
 653          * memory and retry, but that's unlikely to help for a malloc small
 654          * enough to hold a single line of input, anyway.
 655          */
 656         if (errno == ENOMEM)
 657                 die("Out of memory, getdelim failed");
 658
 659         /*
 660          * Restore strbuf invariants; if getdelim left us with a NULL pointer,
 661          * we can just re-init, but otherwise we should make sure that our
 662          * length is empty, and that the result is NUL-terminated.
 663          */
 664         if (!sb->buf)
 665                 strbuf_init(sb, 0);
 666         else
 667                 strbuf_reset(sb);
 668         return EOF;
 669 }
 670 #else
 671 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 672 {
 673         int ch;
 674
 675         if (feof(fp))
 676                 return EOF;
 677
 678         strbuf_reset(sb);
 679         flockfile(fp);
 680         while ((ch = getc_unlocked(fp)) != EOF) {
 681                 if (!strbuf_avail(sb))
 682                         strbuf_grow(sb, 1);
 683                 sb->buf[sb->len++] = ch;
 684                 if (ch == term)
 685                         break;
 686         }
 687         funlockfile(fp);
 688         if (ch == EOF && sb->len == 0)
 689                 return EOF;
 690
 691         sb->buf[sb->len] = '\0';
 692         return 0;
 693 }
 694 #endif
 695
 696 int strbuf_appendwholeline(struct strbuf *sb, FILE *fp, int term)
 697 {
 698         struct strbuf line = STRBUF_INIT;
 699         if (strbuf_getwholeline(&line, fp, term))
 700                 return EOF;
 701         strbuf_addbuf(sb, &line);
 702         strbuf_release(&line);
 703         return 0;
 704 }
 705
 706 static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 707 {
 708         if (strbuf_getwholeline(sb, fp, term))
 709                 return EOF;
 710         if (sb->buf[sb->len - 1] == term)
 711                 strbuf_setlen(sb, sb->len - 1);
 712         return 0;
 713 }
 714
 715 int strbuf_getline(struct strbuf *sb, FILE *fp)
 716 {
 717         if (strbuf_getwholeline(sb, fp, '\n'))
 718                 return EOF;
 719         if (sb->buf[sb->len - 1] == '\n') {
 720                 strbuf_setlen(sb, sb->len - 1);
 721                 if (sb->len && sb->buf[sb->len - 1] == '\r')
 722                         strbuf_setlen(sb, sb->len - 1);
 723         }
 724         return 0;
 725 }
 726
 727 int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 728 {
 729         return strbuf_getdelim(sb, fp, '\n');
 730 }
 731
 732 int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 733 {
 734         return strbuf_getdelim(sb, fp, '\0');
 735 }
 736
 737 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 738 {
 739         strbuf_reset(sb);
 740
 741         while (1) {
 742                 char ch;
 743                 ssize_t len = xread(fd, &ch, 1);
 744                 if (len <= 0)
 745                         return EOF;
 746                 strbuf_addch(sb, ch);
 747                 if (ch == term)
 748                         break;
 749         }
 750         return 0;
 751 }
 752
 753 ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 754 {
 755         int fd;
 756         ssize_t len;
 757         int saved_errno;
 758
 759         fd = open(path, O_RDONLY);
 760         if (fd < 0)
 761                 return -1;
 762         len = strbuf_read(sb, fd, hint);
 763         saved_errno = errno;
 764         close(fd);
 765         if (len < 0) {
 766                 errno = saved_errno;
 767                 return -1;
 768         }
 769
 770         return len;
 771 }
 772
 773 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 774                       const char *buf, size_t size)
 775 {
 776         add_lines(out, prefix, NULL, buf, size);
 777 }
 778
 779 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 780 {
 781         while (*s) {
 782                 size_t len = strcspn(s, "\"<>&");
 783                 strbuf_add(buf, s, len);
 784                 s += len;
 785                 switch (*s) {
 786                 case '"':
 787                         strbuf_addstr(buf, "&quot;");
 788                         break;
 789                 case '<':
 790                         strbuf_addstr(buf, "&lt;");
 791                         break;
 792                 case '>':
 793                         strbuf_addstr(buf, "&gt;");
 794                         break;
 795                 case '&':
 796                         strbuf_addstr(buf, "&amp;");
 797                         break;
 798                 case 0:
 799                         return;
 800                 }
 801                 s++;
 802         }
 803 }
 804
 805 int is_rfc3986_reserved_or_unreserved(char ch)
 806 {
 807         if (is_rfc3986_unreserved(ch))
 808                 return 1;
 809         switch (ch) {
 810                 case '!': case '*': case '\'': case '(': case ')': case ';':
 811                 case ':': case '@': case '&': case '=': case '+': case '$':
 812                 case ',': case '/': case '?': case '#': case '[': case ']':
 813                         return 1;
 814         }
 815         return 0;
 816 }
 817
 818 int is_rfc3986_unreserved(char ch)
 819 {
 820         return isalnum(ch) ||
 821                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 822 }
 823
 824 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 825                                  char_predicate allow_unencoded_fn)
 826 {
 827         strbuf_grow(sb, len);
 828         while (len--) {
 829                 char ch = *s++;
 830                 if (allow_unencoded_fn(ch))
 831                         strbuf_addch(sb, ch);
 832                 else
 833                         strbuf_addf(sb, "%%%02x", (unsigned char)ch);
 834         }
 835 }
 836
 837 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 838                              char_predicate allow_unencoded_fn)
 839 {
 840         strbuf_add_urlencode(sb, s, strlen(s), allow_unencoded_fn);
 841 }
 842
 843 static void strbuf_humanise(struct strbuf *buf, off_t bytes,
 844                                  int humanise_rate)
 845 {
 846         if (bytes > 1 << 30) {
 847                 strbuf_addf(buf,
 848                                 humanise_rate == 0 ?
 849                                         /* TRANSLATORS: IEC 80000-13:2008 gibibyte */
 850                                         _("%u.%2.2u GiB") :
 851                                         /* TRANSLATORS: IEC 80000-13:2008 gibibyte/second */
 852                                         _("%u.%2.2u GiB/s"),
 853                             (unsigned)(bytes >> 30),
 854                             (unsigned)(bytes & ((1 << 30) - 1)) / 10737419);
 855         } else if (bytes > 1 << 20) {
 856                 unsigned x = bytes + 5243;  /* for rounding */
 857                 strbuf_addf(buf,
 858                                 humanise_rate == 0 ?
 859                                         /* TRANSLATORS: IEC 80000-13:2008 mebibyte */
 860                                         _("%u.%2.2u MiB") :
 861                                         /* TRANSLATORS: IEC 80000-13:2008 mebibyte/second */
 862                                         _("%u.%2.2u MiB/s"),
 863                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 864         } else if (bytes > 1 << 10) {
 865                 unsigned x = bytes + 5;  /* for rounding */
 866                 strbuf_addf(buf,
 867                                 humanise_rate == 0 ?
 868                                         /* TRANSLATORS: IEC 80000-13:2008 kibibyte */
 869                                         _("%u.%2.2u KiB") :
 870                                         /* TRANSLATORS: IEC 80000-13:2008 kibibyte/second */
 871                                         _("%u.%2.2u KiB/s"),
 872                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 873         } else {
 874                 strbuf_addf(buf,
 875                                 humanise_rate == 0 ?
 876                                         /* TRANSLATORS: IEC 80000-13:2008 byte */
 877                                         Q_("%u byte", "%u bytes", (unsigned)bytes) :
 878                                         /* TRANSLATORS: IEC 80000-13:2008 byte/second */
 879                                         Q_("%u byte/s", "%u bytes/s", (unsigned)bytes),
 880                                 (unsigned)bytes);
 881         }
 882 }
 883
 884 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 885 {
 886         strbuf_humanise(buf, bytes, 0);
 887 }
 888
 889 void strbuf_humanise_rate(struct strbuf *buf, off_t bytes)
 890 {
 891         strbuf_humanise(buf, bytes, 1);
 892 }
 893
 894 void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 895 {
 896         if (!*path)
 897                 die("The empty string is not a valid path");
 898         if (!is_absolute_path(path)) {
 899                 struct stat cwd_stat, pwd_stat;
 900                 size_t orig_len = sb->len;
 901                 char *cwd = xgetcwd();
 902                 char *pwd = getenv("PWD");
 903                 if (pwd && strcmp(pwd, cwd) &&
 904                     !stat(cwd, &cwd_stat) &&
 905                     (cwd_stat.st_dev || cwd_stat.st_ino) &&
 906                     !stat(pwd, &pwd_stat) &&
 907                     pwd_stat.st_dev == cwd_stat.st_dev &&
 908                     pwd_stat.st_ino == cwd_stat.st_ino)
 909                         strbuf_addstr(sb, pwd);
 910                 else
 911                         strbuf_addstr(sb, cwd);
 912                 if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 913                         strbuf_addch(sb, '/');
 914                 free(cwd);
 915         }
 916         strbuf_addstr(sb, path);
 917 }
 918
 919 void strbuf_add_real_path(struct strbuf *sb, const char *path)
 920 {
 921         if (sb->len) {
 922                 struct strbuf resolved = STRBUF_INIT;
 923                 strbuf_realpath(&resolved, path, 1);
 924                 strbuf_addbuf(sb, &resolved);
 925                 strbuf_release(&resolved);
 926         } else
 927                 strbuf_realpath(sb, path, 1);
 928 }
 929
 930 int printf_ln(const char *fmt, ...)
 931 {
 932         int ret;
 933         va_list ap;
 934         va_start(ap, fmt);
 935         ret = vprintf(fmt, ap);
 936         va_end(ap);
 937         if (ret < 0 || putchar('\n') == EOF)
 938                 return -1;
 939         return ret + 1;
 940 }
 941
 942 int fprintf_ln(FILE *fp, const char *fmt, ...)
 943 {
 944         int ret;
 945         va_list ap;
 946         va_start(ap, fmt);
 947         ret = vfprintf(fp, fmt, ap);
 948         va_end(ap);
 949         if (ret < 0 || putc('\n', fp) == EOF)
 950                 return -1;
 951         return ret + 1;
 952 }
 953
 954 char *xstrdup_tolower(const char *string)
 955 {
 956         char *result;
 957         size_t len, i;
 958
 959         len = strlen(string);
 960         result = xmallocz(len);
 961         for (i = 0; i < len; i++)
 962                 result[i] = tolower(string[i]);
 963         return result;
 964 }
 965
 966 char *xstrdup_toupper(const char *string)
 967 {
 968         char *result;
 969         size_t len, i;
 970
 971         len = strlen(string);
 972         result = xmallocz(len);
 973         for (i = 0; i < len; i++)
 974                 result[i] = toupper(string[i]);
 975         return result;
 976 }
 977
 978 char *xstrvfmt(const char *fmt, va_list ap)
 979 {
 980         struct strbuf buf = STRBUF_INIT;
 981         strbuf_vaddf(&buf, fmt, ap);
 982         return strbuf_detach(&buf, NULL);
 983 }
 984
 985 char *xstrfmt(const char *fmt, ...)
 986 {
 987         va_list ap;
 988         char *ret;
 989
 990         va_start(ap, fmt);
 991         ret = xstrvfmt(fmt, ap);
 992         va_end(ap);
 993
 994         return ret;
 995 }
 996
 997 void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 998                      int tz_offset, int suppress_tz_name)
 999 {
1000         struct strbuf munged_fmt = STRBUF_INIT;
1001         size_t hint = 128;
1002         size_t len;
1003
1004         if (!*fmt)
1005                 return;
1006
1007         /*
1008          * There is no portable way to pass timezone information to
1009          * strftime, so we handle %z and %Z here. Likewise '%s', because
1010          * going back to an epoch time requires knowing the zone.
1011          *
1012          * Note that tz_offset is in the "[-+]HHMM" decimal form; this is what
1013          * we want for %z, but the computation for %s has to convert to number
1014          * of seconds.
1015          */
1016         for (;;) {
1017                 const char *percent = strchrnul(fmt, '%');
1018                 strbuf_add(&munged_fmt, fmt, percent - fmt);
1019                 if (!*percent)
1020                         break;
1021                 fmt = percent + 1;
1022                 switch (*fmt) {
1023                 case '%':
1024                         strbuf_addstr(&munged_fmt, "%%");
1025                         fmt++;
1026                         break;
1027                 case 's':
1028                         strbuf_addf(&munged_fmt, "%"PRItime,
1029                                     (timestamp_t)tm_to_time_t(tm) -
1030                                     3600 * (tz_offset / 100) -
1031                                     60 * (tz_offset % 100));
1032                         fmt++;
1033                         break;
1034                 case 'z':
1035                         strbuf_addf(&munged_fmt, "%+05d", tz_offset);
1036                         fmt++;
1037                         break;
1038                 case 'Z':
1039                         if (suppress_tz_name) {
1040                                 fmt++;
1041                                 break;
1042                         }
1043                         /* FALLTHROUGH */
1044                 default:
1045                         strbuf_addch(&munged_fmt, '%');
1046                 }
1047         }
1048         fmt = munged_fmt.buf;
1049
1050         strbuf_grow(sb, hint);
1051         len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
1052
1053         if (!len) {
1054                 /*
1055                  * strftime reports "0" if it could not fit the result in the buffer.
1056                  * Unfortunately, it also reports "0" if the requested time string
1057                  * takes 0 bytes. So our strategy is to munge the format so that the
1058                  * output contains at least one character, and then drop the extra
1059                  * character before returning.
1060                  */
1061                 strbuf_addch(&munged_fmt, ' ');
1062                 while (!len) {
1063                         hint *= 2;
1064                         strbuf_grow(sb, hint);
1065                         len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
1066                                        munged_fmt.buf, tm);
1067                 }
1068                 len--; /* drop munged space */
1069         }
1070         strbuf_release(&munged_fmt);
1071         strbuf_setlen(sb, sb->len + len);
1072 }
1073
1074 void strbuf_repo_add_unique_abbrev(struct strbuf *sb, struct repository *repo,
1075                                    const struct object_id *oid, int abbrev_len)
1076 {
1077         int r;
1078         strbuf_grow(sb, GIT_MAX_HEXSZ + 1);
1079         r = repo_find_unique_abbrev_r(repo, sb->buf + sb->len, oid, abbrev_len);
1080         strbuf_setlen(sb, sb->len + r);
1081 }
1082
1083 void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
1084                               int abbrev_len)
1085 {
1086         strbuf_repo_add_unique_abbrev(sb, the_repository, oid, abbrev_len);
1087 }
1088
1089 /*
1090  * Returns the length of a line, without trailing spaces.
1091  *
1092  * If the line ends with newline, it will be removed too.
1093  */
1094 static size_t cleanup(char *line, size_t len)
1095 {
1096         while (len) {
1097                 unsigned char c = line[len - 1];
1098                 if (!isspace(c))
1099                         break;
1100                 len--;
1101         }
1102
1103         return len;
1104 }
1105
1106 /*
1107  * Remove empty lines from the beginning and end
1108  * and also trailing spaces from every line.
1109  *
1110  * Turn multiple consecutive empty lines between paragraphs
1111  * into just one empty line.
1112  *
1113  * If the input has only empty lines and spaces,
1114  * no output will be produced.
1115  *
1116  * If last line does not have a newline at the end, one is added.
1117  *
1118  * Enable skip_comments to skip every line starting with comment
1119  * character.
1120  */
1121 void strbuf_stripspace(struct strbuf *sb, int skip_comments)
1122 {
1123         size_t empties = 0;
1124         size_t i, j, len, newlen;
1125         char *eol;
1126
1127         /* We may have to add a newline. */
1128         strbuf_grow(sb, 1);
1129
1130         for (i = j = 0; i < sb->len; i += len, j += newlen) {
1131                 eol = memchr(sb->buf + i, '\n', sb->len - i);
1132                 len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
1133
1134                 if (skip_comments && len && sb->buf[i] == comment_line_char) {
1135                         newlen = 0;
1136                         continue;
1137                 }
1138                 newlen = cleanup(sb->buf + i, len);
1139
1140                 /* Not just an empty line? */
1141                 if (newlen) {
1142                         if (empties > 0 && j > 0)
1143                                 sb->buf[j++] = '\n';
1144                         empties = 0;
1145                         memmove(sb->buf + j, sb->buf + i, newlen);
1146                         sb->buf[newlen + j++] = '\n';
1147                 } else {
1148                         empties++;
1149                 }
1150         }
1151
1152         strbuf_setlen(sb, j);
1153 }
1154
1155 int strbuf_normalize_path(struct strbuf *src)
1156 {
1157         struct strbuf dst = STRBUF_INIT;
1158
1159         strbuf_grow(&dst, src->len);
1160         if (normalize_path_copy(dst.buf, src->buf) < 0) {
1161                 strbuf_release(&dst);
1162                 return -1;
1163         }
1164
1165         /*
1166          * normalize_path does not tell us the new length, so we have to
1167          * compute it by looking for the new NUL it placed
1168          */
1169         strbuf_setlen(&dst, strlen(dst.buf));
1170         strbuf_swap(src, &dst);
1171         strbuf_release(&dst);
1172         return 0;
1173 }
1174
1175 int strbuf_edit_interactively(struct strbuf *buffer, const char *path,
1176                               const char *const *env)
1177 {
1178         char *path2 = NULL;
1179         int fd, res = 0;
1180
1181         if (!is_absolute_path(path))
1182                 path = path2 = xstrdup(git_path("%s", path));
1183
1184         fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0666);
1185         if (fd < 0)
1186                 res = error_errno(_("could not open '%s' for writing"), path);
1187         else if (write_in_full(fd, buffer->buf, buffer->len) < 0) {
1188                 res = error_errno(_("could not write to '%s'"), path);
1189                 close(fd);
1190         } else if (close(fd) < 0)
1191                 res = error_errno(_("could not close '%s'"), path);
1192         else {
1193                 strbuf_reset(buffer);
1194                 if (launch_editor(path, buffer, env) < 0)
1195                         res = error_errno(_("could not edit '%s'"), path);
1196                 unlink(path);
1197         }
1198
1199         free(path2);
1200         return res;
1201 }