strbuf.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "string-list.h"
   4 #include "utf8.h"
   5
   6 int starts_with(const char *str, const char *prefix)
   7 {
   8         for (; ; str++, prefix++)
   9                 if (!*prefix)
  10                         return 1;
  11                 else if (*str != *prefix)
  12                         return 0;
  13 }
  14
  15 int istarts_with(const char *str, const char *prefix)
  16 {
  17         for (; ; str++, prefix++)
  18                 if (!*prefix)
  19                         return 1;
  20                 else if (tolower(*str) != tolower(*prefix))
  21                         return 0;
  22 }
  23
  24 int skip_to_optional_arg_default(const char *str, const char *prefix,
  25                                  const char **arg, const char *def)
  26 {
  27         const char *p;
  28
  29         if (!skip_prefix(str, prefix, &p))
  30                 return 0;
  31
  32         if (!*p) {
  33                 if (arg)
  34                         *arg = def;
  35                 return 1;
  36         }
  37
  38         if (*p != '=')
  39                 return 0;
  40
  41         if (arg)
  42                 *arg = p + 1;
  43         return 1;
  44 }
  45
  46 /*
  47  * Used as the default ->buf value, so that people can always assume
  48  * buf is non NULL and ->buf is NUL terminated even for a freshly
  49  * initialized strbuf.
  50  */
  51 char strbuf_slopbuf[1];
  52
  53 void strbuf_init(struct strbuf *sb, size_t hint)
  54 {
  55         sb->alloc = sb->len = 0;
  56         sb->buf = strbuf_slopbuf;
  57         if (hint)
  58                 strbuf_grow(sb, hint);
  59 }
  60
  61 void strbuf_release(struct strbuf *sb)
  62 {
  63         if (sb->alloc) {
  64                 free(sb->buf);
  65                 strbuf_init(sb, 0);
  66         }
  67 }
  68
  69 char *strbuf_detach(struct strbuf *sb, size_t *sz)
  70 {
  71         char *res;
  72         strbuf_grow(sb, 0);
  73         res = sb->buf;
  74         if (sz)
  75                 *sz = sb->len;
  76         strbuf_init(sb, 0);
  77         return res;
  78 }
  79
  80 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  81 {
  82         strbuf_release(sb);
  83         sb->buf   = buf;
  84         sb->len   = len;
  85         sb->alloc = alloc;
  86         strbuf_grow(sb, 0);
  87         sb->buf[sb->len] = '\0';
  88 }
  89
  90 void strbuf_grow(struct strbuf *sb, size_t extra)
  91 {
  92         int new_buf = !sb->alloc;
  93         if (unsigned_add_overflows(extra, 1) ||
  94             unsigned_add_overflows(sb->len, extra + 1))
  95                 die("you want to use way too much memory");
  96         if (new_buf)
  97                 sb->buf = NULL;
  98         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  99         if (new_buf)
 100                 sb->buf[0] = '\0';
 101 }
 102
 103 void strbuf_trim(struct strbuf *sb)
 104 {
 105         strbuf_rtrim(sb);
 106         strbuf_ltrim(sb);
 107 }
 108
 109 void strbuf_rtrim(struct strbuf *sb)
 110 {
 111         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
 112                 sb->len--;
 113         sb->buf[sb->len] = '\0';
 114 }
 115
 116 void strbuf_trim_trailing_dir_sep(struct strbuf *sb)
 117 {
 118         while (sb->len > 0 && is_dir_sep((unsigned char)sb->buf[sb->len - 1]))
 119                 sb->len--;
 120         sb->buf[sb->len] = '\0';
 121 }
 122
 123 void strbuf_trim_trailing_newline(struct strbuf *sb)
 124 {
 125         if (sb->len > 0 && sb->buf[sb->len - 1] == '\n') {
 126                 if (--sb->len > 0 && sb->buf[sb->len - 1] == '\r')
 127                         --sb->len;
 128                 sb->buf[sb->len] = '\0';
 129         }
 130 }
 131
 132 void strbuf_ltrim(struct strbuf *sb)
 133 {
 134         char *b = sb->buf;
 135         while (sb->len > 0 && isspace(*b)) {
 136                 b++;
 137                 sb->len--;
 138         }
 139         memmove(sb->buf, b, sb->len);
 140         sb->buf[sb->len] = '\0';
 141 }
 142
 143 int strbuf_reencode(struct strbuf *sb, const char *from, const char *to)
 144 {
 145         char *out;
 146         size_t len;
 147
 148         if (same_encoding(from, to))
 149                 return 0;
 150
 151         out = reencode_string_len(sb->buf, sb->len, to, from, &len);
 152         if (!out)
 153                 return -1;
 154
 155         strbuf_attach(sb, out, len, len);
 156         return 0;
 157 }
 158
 159 void strbuf_tolower(struct strbuf *sb)
 160 {
 161         char *p = sb->buf, *end = sb->buf + sb->len;
 162         for (; p < end; p++)
 163                 *p = tolower(*p);
 164 }
 165
 166 struct strbuf **strbuf_split_buf(const char *str, size_t slen,
 167                                  int terminator, int max)
 168 {
 169         struct strbuf **ret = NULL;
 170         size_t nr = 0, alloc = 0;
 171         struct strbuf *t;
 172
 173         while (slen) {
 174                 int len = slen;
 175                 if (max <= 0 || nr + 1 < max) {
 176                         const char *end = memchr(str, terminator, slen);
 177                         if (end)
 178                                 len = end - str + 1;
 179                 }
 180                 t = xmalloc(sizeof(struct strbuf));
 181                 strbuf_init(t, len);
 182                 strbuf_add(t, str, len);
 183                 ALLOC_GROW(ret, nr + 2, alloc);
 184                 ret[nr++] = t;
 185                 str += len;
 186                 slen -= len;
 187         }
 188         ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 189         ret[nr] = NULL;
 190         return ret;
 191 }
 192
 193 void strbuf_add_separated_string_list(struct strbuf *str,
 194                                       const char *sep,
 195                                       struct string_list *slist)
 196 {
 197         struct string_list_item *item;
 198         int sep_needed = 0;
 199
 200         for_each_string_list_item(item, slist) {
 201                 if (sep_needed)
 202                         strbuf_addstr(str, sep);
 203                 strbuf_addstr(str, item->string);
 204                 sep_needed = 1;
 205         }
 206 }
 207
 208 void strbuf_list_free(struct strbuf **sbs)
 209 {
 210         struct strbuf **s = sbs;
 211
 212         while (*s) {
 213                 strbuf_release(*s);
 214                 free(*s++);
 215         }
 216         free(sbs);
 217 }
 218
 219 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 220 {
 221         size_t len = a->len < b->len ? a->len: b->len;
 222         int cmp = memcmp(a->buf, b->buf, len);
 223         if (cmp)
 224                 return cmp;
 225         return a->len < b->len ? -1: a->len != b->len;
 226 }
 227
 228 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 229                                    const void *data, size_t dlen)
 230 {
 231         if (unsigned_add_overflows(pos, len))
 232                 die("you want to use way too much memory");
 233         if (pos > sb->len)
 234                 die("`pos' is too far after the end of the buffer");
 235         if (pos + len > sb->len)
 236                 die("`pos + len' is too far after the end of the buffer");
 237
 238         if (dlen >= len)
 239                 strbuf_grow(sb, dlen - len);
 240         memmove(sb->buf + pos + dlen,
 241                         sb->buf + pos + len,
 242                         sb->len - pos - len);
 243         memcpy(sb->buf + pos, data, dlen);
 244         strbuf_setlen(sb, sb->len + dlen - len);
 245 }
 246
 247 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 248 {
 249         strbuf_splice(sb, pos, 0, data, len);
 250 }
 251
 252 void strbuf_vinsertf(struct strbuf *sb, size_t pos, const char *fmt, va_list ap)
 253 {
 254         int len, len2;
 255         char save;
 256         va_list cp;
 257
 258         if (pos > sb->len)
 259                 die("`pos' is too far after the end of the buffer");
 260         va_copy(cp, ap);
 261         len = vsnprintf(sb->buf + sb->len, 0, fmt, cp);
 262         va_end(cp);
 263         if (len < 0)
 264                 BUG("your vsnprintf is broken (returned %d)", len);
 265         if (!len)
 266                 return; /* nothing to do */
 267         if (unsigned_add_overflows(sb->len, len))
 268                 die("you want to use way too much memory");
 269         strbuf_grow(sb, len);
 270         memmove(sb->buf + pos + len, sb->buf + pos, sb->len - pos);
 271         /* vsnprintf() will append a NUL, overwriting one of our characters */
 272         save = sb->buf[pos + len];
 273         len2 = vsnprintf(sb->buf + pos, len + 1, fmt, ap);
 274         sb->buf[pos + len] = save;
 275         if (len2 != len)
 276                 BUG("your vsnprintf is broken (returns inconsistent lengths)");
 277         strbuf_setlen(sb, sb->len + len);
 278 }
 279
 280 void strbuf_insertf(struct strbuf *sb, size_t pos, const char *fmt, ...)
 281 {
 282         va_list ap;
 283         va_start(ap, fmt);
 284         strbuf_vinsertf(sb, pos, fmt, ap);
 285         va_end(ap);
 286 }
 287
 288 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 289 {
 290         strbuf_splice(sb, pos, len, "", 0);
 291 }
 292
 293 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 294 {
 295         strbuf_grow(sb, len);
 296         memcpy(sb->buf + sb->len, data, len);
 297         strbuf_setlen(sb, sb->len + len);
 298 }
 299
 300 void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
 301 {
 302         strbuf_grow(sb, sb2->len);
 303         memcpy(sb->buf + sb->len, sb2->buf, sb2->len);
 304         strbuf_setlen(sb, sb->len + sb2->len);
 305 }
 306
 307 const char *strbuf_join_argv(struct strbuf *buf,
 308                              int argc, const char **argv, char delim)
 309 {
 310         if (!argc)
 311                 return buf->buf;
 312
 313         strbuf_addstr(buf, *argv);
 314         while (--argc) {
 315                 strbuf_addch(buf, delim);
 316                 strbuf_addstr(buf, *(++argv));
 317         }
 318
 319         return buf->buf;
 320 }
 321
 322 void strbuf_addchars(struct strbuf *sb, int c, size_t n)
 323 {
 324         strbuf_grow(sb, n);
 325         memset(sb->buf + sb->len, c, n);
 326         strbuf_setlen(sb, sb->len + n);
 327 }
 328
 329 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 330 {
 331         va_list ap;
 332         va_start(ap, fmt);
 333         strbuf_vaddf(sb, fmt, ap);
 334         va_end(ap);
 335 }
 336
 337 static void add_lines(struct strbuf *out,
 338                         const char *prefix1,
 339                         const char *prefix2,
 340                         const char *buf, size_t size)
 341 {
 342         while (size) {
 343                 const char *prefix;
 344                 const char *next = memchr(buf, '\n', size);
 345                 next = next ? (next + 1) : (buf + size);
 346
 347                 prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
 348                           ? prefix2 : prefix1);
 349                 strbuf_addstr(out, prefix);
 350                 strbuf_add(out, buf, next - buf);
 351                 size -= next - buf;
 352                 buf = next;
 353         }
 354         strbuf_complete_line(out);
 355 }
 356
 357 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 358 {
 359         static char prefix1[3];
 360         static char prefix2[2];
 361
 362         if (prefix1[0] != comment_line_char) {
 363                 xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
 364                 xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
 365         }
 366         add_lines(out, prefix1, prefix2, buf, size);
 367 }
 368
 369 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 370 {
 371         va_list params;
 372         struct strbuf buf = STRBUF_INIT;
 373         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 374
 375         va_start(params, fmt);
 376         strbuf_vaddf(&buf, fmt, params);
 377         va_end(params);
 378
 379         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 380         if (incomplete_line)
 381                 sb->buf[--sb->len] = '\0';
 382
 383         strbuf_release(&buf);
 384 }
 385
 386 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 387 {
 388         int len;
 389         va_list cp;
 390
 391         if (!strbuf_avail(sb))
 392                 strbuf_grow(sb, 64);
 393         va_copy(cp, ap);
 394         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 395         va_end(cp);
 396         if (len < 0)
 397                 BUG("your vsnprintf is broken (returned %d)", len);
 398         if (len > strbuf_avail(sb)) {
 399                 strbuf_grow(sb, len);
 400                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 401                 if (len > strbuf_avail(sb))
 402                         BUG("your vsnprintf is broken (insatiable)");
 403         }
 404         strbuf_setlen(sb, sb->len + len);
 405 }
 406
 407 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 408                    void *context)
 409 {
 410         for (;;) {
 411                 const char *percent;
 412                 size_t consumed;
 413
 414                 percent = strchrnul(format, '%');
 415                 strbuf_add(sb, format, percent - format);
 416                 if (!*percent)
 417                         break;
 418                 format = percent + 1;
 419
 420                 if (*format == '%') {
 421                         strbuf_addch(sb, '%');
 422                         format++;
 423                         continue;
 424                 }
 425
 426                 consumed = fn(sb, format, context);
 427                 if (consumed)
 428                         format += consumed;
 429                 else
 430                         strbuf_addch(sb, '%');
 431         }
 432 }
 433
 434 size_t strbuf_expand_literal_cb(struct strbuf *sb,
 435                                 const char *placeholder,
 436                                 void *context)
 437 {
 438         int ch;
 439
 440         switch (placeholder[0]) {
 441         case 'n':               /* newline */
 442                 strbuf_addch(sb, '\n');
 443                 return 1;
 444         case 'x':
 445                 /* %x00 == NUL, %x0a == LF, etc. */
 446                 ch = hex2chr(placeholder + 1);
 447                 if (ch < 0)
 448                         return 0;
 449                 strbuf_addch(sb, ch);
 450                 return 3;
 451         }
 452         return 0;
 453 }
 454
 455 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 456                 void *context)
 457 {
 458         struct strbuf_expand_dict_entry *e = context;
 459         size_t len;
 460
 461         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 462                 if (!strncmp(placeholder, e->placeholder, len)) {
 463                         if (e->value)
 464                                 strbuf_addstr(sb, e->value);
 465                         return len;
 466                 }
 467         }
 468         return 0;
 469 }
 470
 471 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 472 {
 473         size_t i, len = src->len;
 474
 475         for (i = 0; i < len; i++) {
 476                 if (src->buf[i] == '%')
 477                         strbuf_addch(dst, '%');
 478                 strbuf_addch(dst, src->buf[i]);
 479         }
 480 }
 481
 482 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 483 {
 484         size_t res;
 485         size_t oldalloc = sb->alloc;
 486
 487         strbuf_grow(sb, size);
 488         res = fread(sb->buf + sb->len, 1, size, f);
 489         if (res > 0)
 490                 strbuf_setlen(sb, sb->len + res);
 491         else if (oldalloc == 0)
 492                 strbuf_release(sb);
 493         return res;
 494 }
 495
 496 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 497 {
 498         size_t oldlen = sb->len;
 499         size_t oldalloc = sb->alloc;
 500
 501         strbuf_grow(sb, hint ? hint : 8192);
 502         for (;;) {
 503                 ssize_t want = sb->alloc - sb->len - 1;
 504                 ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
 505
 506                 if (got < 0) {
 507                         if (oldalloc == 0)
 508                                 strbuf_release(sb);
 509                         else
 510                                 strbuf_setlen(sb, oldlen);
 511                         return -1;
 512                 }
 513                 sb->len += got;
 514                 if (got < want)
 515                         break;
 516                 strbuf_grow(sb, 8192);
 517         }
 518
 519         sb->buf[sb->len] = '\0';
 520         return sb->len - oldlen;
 521 }
 522
 523 ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
 524 {
 525         size_t oldalloc = sb->alloc;
 526         ssize_t cnt;
 527
 528         strbuf_grow(sb, hint ? hint : 8192);
 529         cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 530         if (cnt > 0)
 531                 strbuf_setlen(sb, sb->len + cnt);
 532         else if (oldalloc == 0)
 533                 strbuf_release(sb);
 534         return cnt;
 535 }
 536
 537 ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 538 {
 539         return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 540 }
 541
 542 ssize_t strbuf_write_fd(struct strbuf *sb, int fd)
 543 {
 544         return sb->len ? write(fd, sb->buf, sb->len) : 0;
 545 }
 546
 547 #define STRBUF_MAXLINK (2*PATH_MAX)
 548
 549 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 550 {
 551         size_t oldalloc = sb->alloc;
 552
 553         if (hint < 32)
 554                 hint = 32;
 555
 556         while (hint < STRBUF_MAXLINK) {
 557                 ssize_t len;
 558
 559                 strbuf_grow(sb, hint);
 560                 len = readlink(path, sb->buf, hint);
 561                 if (len < 0) {
 562                         if (errno != ERANGE)
 563                                 break;
 564                 } else if (len < hint) {
 565                         strbuf_setlen(sb, len);
 566                         return 0;
 567                 }
 568
 569                 /* .. the buffer was too small - try again */
 570                 hint *= 2;
 571         }
 572         if (oldalloc == 0)
 573                 strbuf_release(sb);
 574         return -1;
 575 }
 576
 577 int strbuf_getcwd(struct strbuf *sb)
 578 {
 579         size_t oldalloc = sb->alloc;
 580         size_t guessed_len = 128;
 581
 582         for (;; guessed_len *= 2) {
 583                 strbuf_grow(sb, guessed_len);
 584                 if (getcwd(sb->buf, sb->alloc)) {
 585                         strbuf_setlen(sb, strlen(sb->buf));
 586                         return 0;
 587                 }
 588
 589                 /*
 590                  * If getcwd(3) is implemented as a syscall that falls
 591                  * back to a regular lookup using readdir(3) etc. then
 592                  * we may be able to avoid EACCES by providing enough
 593                  * space to the syscall as it's not necessarily bound
 594                  * to the same restrictions as the fallback.
 595                  */
 596                 if (errno == EACCES && guessed_len < PATH_MAX)
 597                         continue;
 598
 599                 if (errno != ERANGE)
 600                         break;
 601         }
 602         if (oldalloc == 0)
 603                 strbuf_release(sb);
 604         else
 605                 strbuf_reset(sb);
 606         return -1;
 607 }
 608
 609 #ifdef HAVE_GETDELIM
 610 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 611 {
 612         ssize_t r;
 613
 614         if (feof(fp))
 615                 return EOF;
 616
 617         strbuf_reset(sb);
 618
 619         /* Translate slopbuf to NULL, as we cannot call realloc on it */
 620         if (!sb->alloc)
 621                 sb->buf = NULL;
 622         errno = 0;
 623         r = getdelim(&sb->buf, &sb->alloc, term, fp);
 624
 625         if (r > 0) {
 626                 sb->len = r;
 627                 return 0;
 628         }
 629         assert(r == -1);
 630
 631         /*
 632          * Normally we would have called xrealloc, which will try to free
 633          * memory and recover. But we have no way to tell getdelim() to do so.
 634          * Worse, we cannot try to recover ENOMEM ourselves, because we have
 635          * no idea how many bytes were read by getdelim.
 636          *
 637          * Dying here is reasonable. It mirrors what xrealloc would do on
 638          * catastrophic memory failure. We skip the opportunity to free pack
 639          * memory and retry, but that's unlikely to help for a malloc small
 640          * enough to hold a single line of input, anyway.
 641          */
 642         if (errno == ENOMEM)
 643                 die("Out of memory, getdelim failed");
 644
 645         /*
 646          * Restore strbuf invariants; if getdelim left us with a NULL pointer,
 647          * we can just re-init, but otherwise we should make sure that our
 648          * length is empty, and that the result is NUL-terminated.
 649          */
 650         if (!sb->buf)
 651                 strbuf_init(sb, 0);
 652         else
 653                 strbuf_reset(sb);
 654         return EOF;
 655 }
 656 #else
 657 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 658 {
 659         int ch;
 660
 661         if (feof(fp))
 662                 return EOF;
 663
 664         strbuf_reset(sb);
 665         flockfile(fp);
 666         while ((ch = getc_unlocked(fp)) != EOF) {
 667                 if (!strbuf_avail(sb))
 668                         strbuf_grow(sb, 1);
 669                 sb->buf[sb->len++] = ch;
 670                 if (ch == term)
 671                         break;
 672         }
 673         funlockfile(fp);
 674         if (ch == EOF && sb->len == 0)
 675                 return EOF;
 676
 677         sb->buf[sb->len] = '\0';
 678         return 0;
 679 }
 680 #endif
 681
 682 static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 683 {
 684         if (strbuf_getwholeline(sb, fp, term))
 685                 return EOF;
 686         if (sb->buf[sb->len - 1] == term)
 687                 strbuf_setlen(sb, sb->len - 1);
 688         return 0;
 689 }
 690
 691 int strbuf_getline(struct strbuf *sb, FILE *fp)
 692 {
 693         if (strbuf_getwholeline(sb, fp, '\n'))
 694                 return EOF;
 695         if (sb->buf[sb->len - 1] == '\n') {
 696                 strbuf_setlen(sb, sb->len - 1);
 697                 if (sb->len && sb->buf[sb->len - 1] == '\r')
 698                         strbuf_setlen(sb, sb->len - 1);
 699         }
 700         return 0;
 701 }
 702
 703 int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 704 {
 705         return strbuf_getdelim(sb, fp, '\n');
 706 }
 707
 708 int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 709 {
 710         return strbuf_getdelim(sb, fp, '\0');
 711 }
 712
 713 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 714 {
 715         strbuf_reset(sb);
 716
 717         while (1) {
 718                 char ch;
 719                 ssize_t len = xread(fd, &ch, 1);
 720                 if (len <= 0)
 721                         return EOF;
 722                 strbuf_addch(sb, ch);
 723                 if (ch == term)
 724                         break;
 725         }
 726         return 0;
 727 }
 728
 729 ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 730 {
 731         int fd;
 732         ssize_t len;
 733         int saved_errno;
 734
 735         fd = open(path, O_RDONLY);
 736         if (fd < 0)
 737                 return -1;
 738         len = strbuf_read(sb, fd, hint);
 739         saved_errno = errno;
 740         close(fd);
 741         if (len < 0) {
 742                 errno = saved_errno;
 743                 return -1;
 744         }
 745
 746         return len;
 747 }
 748
 749 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 750                       const char *buf, size_t size)
 751 {
 752         add_lines(out, prefix, NULL, buf, size);
 753 }
 754
 755 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 756 {
 757         while (*s) {
 758                 size_t len = strcspn(s, "\"<>&");
 759                 strbuf_add(buf, s, len);
 760                 s += len;
 761                 switch (*s) {
 762                 case '"':
 763                         strbuf_addstr(buf, "&quot;");
 764                         break;
 765                 case '<':
 766                         strbuf_addstr(buf, "&lt;");
 767                         break;
 768                 case '>':
 769                         strbuf_addstr(buf, "&gt;");
 770                         break;
 771                 case '&':
 772                         strbuf_addstr(buf, "&amp;");
 773                         break;
 774                 case 0:
 775                         return;
 776                 }
 777                 s++;
 778         }
 779 }
 780
 781 int is_rfc3986_reserved_or_unreserved(char ch)
 782 {
 783         if (is_rfc3986_unreserved(ch))
 784                 return 1;
 785         switch (ch) {
 786                 case '!': case '*': case '\'': case '(': case ')': case ';':
 787                 case ':': case '@': case '&': case '=': case '+': case '$':
 788                 case ',': case '/': case '?': case '#': case '[': case ']':
 789                         return 1;
 790         }
 791         return 0;
 792 }
 793
 794 int is_rfc3986_unreserved(char ch)
 795 {
 796         return isalnum(ch) ||
 797                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 798 }
 799
 800 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 801                                  char_predicate allow_unencoded_fn)
 802 {
 803         strbuf_grow(sb, len);
 804         while (len--) {
 805                 char ch = *s++;
 806                 if (allow_unencoded_fn(ch))
 807                         strbuf_addch(sb, ch);
 808                 else
 809                         strbuf_addf(sb, "%%%02x", (unsigned char)ch);
 810         }
 811 }
 812
 813 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 814                              char_predicate allow_unencoded_fn)
 815 {
 816         strbuf_add_urlencode(sb, s, strlen(s), allow_unencoded_fn);
 817 }
 818
 819 static void strbuf_humanise(struct strbuf *buf, off_t bytes,
 820                                  int humanise_rate)
 821 {
 822         if (bytes > 1 << 30) {
 823                 strbuf_addf(buf,
 824                                 humanise_rate == 0 ?
 825                                         /* TRANSLATORS: IEC 80000-13:2008 gibibyte */
 826                                         _("%u.%2.2u GiB") :
 827                                         /* TRANSLATORS: IEC 80000-13:2008 gibibyte/second */
 828                                         _("%u.%2.2u GiB/s"),
 829                             (unsigned)(bytes >> 30),
 830                             (unsigned)(bytes & ((1 << 30) - 1)) / 10737419);
 831         } else if (bytes > 1 << 20) {
 832                 unsigned x = bytes + 5243;  /* for rounding */
 833                 strbuf_addf(buf,
 834                                 humanise_rate == 0 ?
 835                                         /* TRANSLATORS: IEC 80000-13:2008 mebibyte */
 836                                         _("%u.%2.2u MiB") :
 837                                         /* TRANSLATORS: IEC 80000-13:2008 mebibyte/second */
 838                                         _("%u.%2.2u MiB/s"),
 839                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 840         } else if (bytes > 1 << 10) {
 841                 unsigned x = bytes + 5;  /* for rounding */
 842                 strbuf_addf(buf,
 843                                 humanise_rate == 0 ?
 844                                         /* TRANSLATORS: IEC 80000-13:2008 kibibyte */
 845                                         _("%u.%2.2u KiB") :
 846                                         /* TRANSLATORS: IEC 80000-13:2008 kibibyte/second */
 847                                         _("%u.%2.2u KiB/s"),
 848                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 849         } else {
 850                 strbuf_addf(buf,
 851                                 humanise_rate == 0 ?
 852                                         /* TRANSLATORS: IEC 80000-13:2008 byte */
 853                                         Q_("%u byte", "%u bytes", (unsigned)bytes) :
 854                                         /* TRANSLATORS: IEC 80000-13:2008 byte/second */
 855                                         Q_("%u byte/s", "%u bytes/s", (unsigned)bytes),
 856                                 (unsigned)bytes);
 857         }
 858 }
 859
 860 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 861 {
 862         strbuf_humanise(buf, bytes, 0);
 863 }
 864
 865 void strbuf_humanise_rate(struct strbuf *buf, off_t bytes)
 866 {
 867         strbuf_humanise(buf, bytes, 1);
 868 }
 869
 870 void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 871 {
 872         if (!*path)
 873                 die("The empty string is not a valid path");
 874         if (!is_absolute_path(path)) {
 875                 struct stat cwd_stat, pwd_stat;
 876                 size_t orig_len = sb->len;
 877                 char *cwd = xgetcwd();
 878                 char *pwd = getenv("PWD");
 879                 if (pwd && strcmp(pwd, cwd) &&
 880                     !stat(cwd, &cwd_stat) &&
 881                     (cwd_stat.st_dev || cwd_stat.st_ino) &&
 882                     !stat(pwd, &pwd_stat) &&
 883                     pwd_stat.st_dev == cwd_stat.st_dev &&
 884                     pwd_stat.st_ino == cwd_stat.st_ino)
 885                         strbuf_addstr(sb, pwd);
 886                 else
 887                         strbuf_addstr(sb, cwd);
 888                 if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 889                         strbuf_addch(sb, '/');
 890                 free(cwd);
 891         }
 892         strbuf_addstr(sb, path);
 893 }
 894
 895 void strbuf_add_real_path(struct strbuf *sb, const char *path)
 896 {
 897         if (sb->len) {
 898                 struct strbuf resolved = STRBUF_INIT;
 899                 strbuf_realpath(&resolved, path, 1);
 900                 strbuf_addbuf(sb, &resolved);
 901                 strbuf_release(&resolved);
 902         } else
 903                 strbuf_realpath(sb, path, 1);
 904 }
 905
 906 int printf_ln(const char *fmt, ...)
 907 {
 908         int ret;
 909         va_list ap;
 910         va_start(ap, fmt);
 911         ret = vprintf(fmt, ap);
 912         va_end(ap);
 913         if (ret < 0 || putchar('\n') == EOF)
 914                 return -1;
 915         return ret + 1;
 916 }
 917
 918 int fprintf_ln(FILE *fp, const char *fmt, ...)
 919 {
 920         int ret;
 921         va_list ap;
 922         va_start(ap, fmt);
 923         ret = vfprintf(fp, fmt, ap);
 924         va_end(ap);
 925         if (ret < 0 || putc('\n', fp) == EOF)
 926                 return -1;
 927         return ret + 1;
 928 }
 929
 930 char *xstrdup_tolower(const char *string)
 931 {
 932         char *result;
 933         size_t len, i;
 934
 935         len = strlen(string);
 936         result = xmallocz(len);
 937         for (i = 0; i < len; i++)
 938                 result[i] = tolower(string[i]);
 939         return result;
 940 }
 941
 942 char *xstrdup_toupper(const char *string)
 943 {
 944         char *result;
 945         size_t len, i;
 946
 947         len = strlen(string);
 948         result = xmallocz(len);
 949         for (i = 0; i < len; i++)
 950                 result[i] = toupper(string[i]);
 951         return result;
 952 }
 953
 954 char *xstrvfmt(const char *fmt, va_list ap)
 955 {
 956         struct strbuf buf = STRBUF_INIT;
 957         strbuf_vaddf(&buf, fmt, ap);
 958         return strbuf_detach(&buf, NULL);
 959 }
 960
 961 char *xstrfmt(const char *fmt, ...)
 962 {
 963         va_list ap;
 964         char *ret;
 965
 966         va_start(ap, fmt);
 967         ret = xstrvfmt(fmt, ap);
 968         va_end(ap);
 969
 970         return ret;
 971 }
 972
 973 void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 974                      int tz_offset, int suppress_tz_name)
 975 {
 976         struct strbuf munged_fmt = STRBUF_INIT;
 977         size_t hint = 128;
 978         size_t len;
 979
 980         if (!*fmt)
 981                 return;
 982
 983         /*
 984          * There is no portable way to pass timezone information to
 985          * strftime, so we handle %z and %Z here.
 986          */
 987         for (;;) {
 988                 const char *percent = strchrnul(fmt, '%');
 989                 strbuf_add(&munged_fmt, fmt, percent - fmt);
 990                 if (!*percent)
 991                         break;
 992                 fmt = percent + 1;
 993                 switch (*fmt) {
 994                 case '%':
 995                         strbuf_addstr(&munged_fmt, "%%");
 996                         fmt++;
 997                         break;
 998                 case 'z':
 999                         strbuf_addf(&munged_fmt, "%+05d", tz_offset);
1000                         fmt++;
1001                         break;
1002                 case 'Z':
1003                         if (suppress_tz_name) {
1004                                 fmt++;
1005                                 break;
1006                         }
1007                         /* FALLTHROUGH */
1008                 default:
1009                         strbuf_addch(&munged_fmt, '%');
1010                 }
1011         }
1012         fmt = munged_fmt.buf;
1013
1014         strbuf_grow(sb, hint);
1015         len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
1016
1017         if (!len) {
1018                 /*
1019                  * strftime reports "0" if it could not fit the result in the buffer.
1020                  * Unfortunately, it also reports "0" if the requested time string
1021                  * takes 0 bytes. So our strategy is to munge the format so that the
1022                  * output contains at least one character, and then drop the extra
1023                  * character before returning.
1024                  */
1025                 strbuf_addch(&munged_fmt, ' ');
1026                 while (!len) {
1027                         hint *= 2;
1028                         strbuf_grow(sb, hint);
1029                         len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
1030                                        munged_fmt.buf, tm);
1031                 }
1032                 len--; /* drop munged space */
1033         }
1034         strbuf_release(&munged_fmt);
1035         strbuf_setlen(sb, sb->len + len);
1036 }
1037
1038 void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
1039                               int abbrev_len)
1040 {
1041         int r;
1042         strbuf_grow(sb, GIT_MAX_HEXSZ + 1);
1043         r = find_unique_abbrev_r(sb->buf + sb->len, oid, abbrev_len);
1044         strbuf_setlen(sb, sb->len + r);
1045 }
1046
1047 /*
1048  * Returns the length of a line, without trailing spaces.
1049  *
1050  * If the line ends with newline, it will be removed too.
1051  */
1052 static size_t cleanup(char *line, size_t len)
1053 {
1054         while (len) {
1055                 unsigned char c = line[len - 1];
1056                 if (!isspace(c))
1057                         break;
1058                 len--;
1059         }
1060
1061         return len;
1062 }
1063
1064 /*
1065  * Remove empty lines from the beginning and end
1066  * and also trailing spaces from every line.
1067  *
1068  * Turn multiple consecutive empty lines between paragraphs
1069  * into just one empty line.
1070  *
1071  * If the input has only empty lines and spaces,
1072  * no output will be produced.
1073  *
1074  * If last line does not have a newline at the end, one is added.
1075  *
1076  * Enable skip_comments to skip every line starting with comment
1077  * character.
1078  */
1079 void strbuf_stripspace(struct strbuf *sb, int skip_comments)
1080 {
1081         size_t empties = 0;
1082         size_t i, j, len, newlen;
1083         char *eol;
1084
1085         /* We may have to add a newline. */
1086         strbuf_grow(sb, 1);
1087
1088         for (i = j = 0; i < sb->len; i += len, j += newlen) {
1089                 eol = memchr(sb->buf + i, '\n', sb->len - i);
1090                 len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
1091
1092                 if (skip_comments && len && sb->buf[i] == comment_line_char) {
1093                         newlen = 0;
1094                         continue;
1095                 }
1096                 newlen = cleanup(sb->buf + i, len);
1097
1098                 /* Not just an empty line? */
1099                 if (newlen) {
1100                         if (empties > 0 && j > 0)
1101                                 sb->buf[j++] = '\n';
1102                         empties = 0;
1103                         memmove(sb->buf + j, sb->buf + i, newlen);
1104                         sb->buf[newlen + j++] = '\n';
1105                 } else {
1106                         empties++;
1107                 }
1108         }
1109
1110         strbuf_setlen(sb, j);
1111 }
1112
1113 int strbuf_normalize_path(struct strbuf *src)
1114 {
1115         struct strbuf dst = STRBUF_INIT;
1116
1117         strbuf_grow(&dst, src->len);
1118         if (normalize_path_copy(dst.buf, src->buf) < 0) {
1119                 strbuf_release(&dst);
1120                 return -1;
1121         }
1122
1123         /*
1124          * normalize_path does not tell us the new length, so we have to
1125          * compute it by looking for the new NUL it placed
1126          */
1127         strbuf_setlen(&dst, strlen(dst.buf));
1128         strbuf_swap(src, &dst);
1129         strbuf_release(&dst);
1130         return 0;
1131 }
1132
1133 int strbuf_edit_interactively(struct strbuf *buffer, const char *path,
1134                               const char *const *env)
1135 {
1136         char *path2 = NULL;
1137         int fd, res = 0;
1138
1139         if (!is_absolute_path(path))
1140                 path = path2 = xstrdup(git_path("%s", path));
1141
1142         fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0666);
1143         if (fd < 0)
1144                 res = error_errno(_("could not open '%s' for writing"), path);
1145         else if (write_in_full(fd, buffer->buf, buffer->len) < 0) {
1146                 res = error_errno(_("could not write to '%s'"), path);
1147                 close(fd);
1148         } else if (close(fd) < 0)
1149                 res = error_errno(_("could not close '%s'"), path);
1150         else {
1151                 strbuf_reset(buffer);
1152                 if (launch_editor(path, buffer, env) < 0)
1153                         res = error_errno(_("could not edit '%s'"), path);
1154                 unlink(path);
1155         }
1156
1157         free(path2);
1158         return res;
1159 }