strbuf.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "string-list.h"
   4 #include "utf8.h"
   5 #include "date.h"
   6
   7 int starts_with(const char *str, const char *prefix)
   8 {
   9         for (; ; str++, prefix++)
  10                 if (!*prefix)
  11                         return 1;
  12                 else if (*str != *prefix)
  13                         return 0;
  14 }
  15
  16 int istarts_with(const char *str, const char *prefix)
  17 {
  18         for (; ; str++, prefix++)
  19                 if (!*prefix)
  20                         return 1;
  21                 else if (tolower(*str) != tolower(*prefix))
  22                         return 0;
  23 }
  24
  25 int skip_to_optional_arg_default(const char *str, const char *prefix,
  26                                  const char **arg, const char *def)
  27 {
  28         const char *p;
  29
  30         if (!skip_prefix(str, prefix, &p))
  31                 return 0;
  32
  33         if (!*p) {
  34                 if (arg)
  35                         *arg = def;
  36                 return 1;
  37         }
  38
  39         if (*p != '=')
  40                 return 0;
  41
  42         if (arg)
  43                 *arg = p + 1;
  44         return 1;
  45 }
  46
  47 /*
  48  * Used as the default ->buf value, so that people can always assume
  49  * buf is non NULL and ->buf is NUL terminated even for a freshly
  50  * initialized strbuf.
  51  */
  52 char strbuf_slopbuf[1];
  53
  54 void strbuf_init(struct strbuf *sb, size_t hint)
  55 {
  56         struct strbuf blank = STRBUF_INIT;
  57         memcpy(sb, &blank, sizeof(*sb));
  58         if (hint)
  59                 strbuf_grow(sb, hint);
  60 }
  61
  62 void strbuf_release(struct strbuf *sb)
  63 {
  64         if (sb->alloc) {
  65                 free(sb->buf);
  66                 strbuf_init(sb, 0);
  67         }
  68 }
  69
  70 char *strbuf_detach(struct strbuf *sb, size_t *sz)
  71 {
  72         char *res;
  73         strbuf_grow(sb, 0);
  74         res = sb->buf;
  75         if (sz)
  76                 *sz = sb->len;
  77         strbuf_init(sb, 0);
  78         return res;
  79 }
  80
  81 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  82 {
  83         strbuf_release(sb);
  84         sb->buf   = buf;
  85         sb->len   = len;
  86         sb->alloc = alloc;
  87         strbuf_grow(sb, 0);
  88         sb->buf[sb->len] = '\0';
  89 }
  90
  91 void strbuf_grow(struct strbuf *sb, size_t extra)
  92 {
  93         int new_buf = !sb->alloc;
  94         if (unsigned_add_overflows(extra, 1) ||
  95             unsigned_add_overflows(sb->len, extra + 1))
  96                 die("you want to use way too much memory");
  97         if (new_buf)
  98                 sb->buf = NULL;
  99         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
 100         if (new_buf)
 101                 sb->buf[0] = '\0';
 102 }
 103
 104 void strbuf_trim(struct strbuf *sb)
 105 {
 106         strbuf_rtrim(sb);
 107         strbuf_ltrim(sb);
 108 }
 109
 110 void strbuf_rtrim(struct strbuf *sb)
 111 {
 112         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
 113                 sb->len--;
 114         sb->buf[sb->len] = '\0';
 115 }
 116
 117 void strbuf_trim_trailing_dir_sep(struct strbuf *sb)
 118 {
 119         while (sb->len > 0 && is_dir_sep((unsigned char)sb->buf[sb->len - 1]))
 120                 sb->len--;
 121         sb->buf[sb->len] = '\0';
 122 }
 123
 124 void strbuf_trim_trailing_newline(struct strbuf *sb)
 125 {
 126         if (sb->len > 0 && sb->buf[sb->len - 1] == '\n') {
 127                 if (--sb->len > 0 && sb->buf[sb->len - 1] == '\r')
 128                         --sb->len;
 129                 sb->buf[sb->len] = '\0';
 130         }
 131 }
 132
 133 void strbuf_ltrim(struct strbuf *sb)
 134 {
 135         char *b = sb->buf;
 136         while (sb->len > 0 && isspace(*b)) {
 137                 b++;
 138                 sb->len--;
 139         }
 140         memmove(sb->buf, b, sb->len);
 141         sb->buf[sb->len] = '\0';
 142 }
 143
 144 int strbuf_reencode(struct strbuf *sb, const char *from, const char *to)
 145 {
 146         char *out;
 147         size_t len;
 148
 149         if (same_encoding(from, to))
 150                 return 0;
 151
 152         out = reencode_string_len(sb->buf, sb->len, to, from, &len);
 153         if (!out)
 154                 return -1;
 155
 156         strbuf_attach(sb, out, len, len);
 157         return 0;
 158 }
 159
 160 void strbuf_tolower(struct strbuf *sb)
 161 {
 162         char *p = sb->buf, *end = sb->buf + sb->len;
 163         for (; p < end; p++)
 164                 *p = tolower(*p);
 165 }
 166
 167 struct strbuf **strbuf_split_buf(const char *str, size_t slen,
 168                                  int terminator, int max)
 169 {
 170         struct strbuf **ret = NULL;
 171         size_t nr = 0, alloc = 0;
 172         struct strbuf *t;
 173
 174         while (slen) {
 175                 int len = slen;
 176                 if (max <= 0 || nr + 1 < max) {
 177                         const char *end = memchr(str, terminator, slen);
 178                         if (end)
 179                                 len = end - str + 1;
 180                 }
 181                 t = xmalloc(sizeof(struct strbuf));
 182                 strbuf_init(t, len);
 183                 strbuf_add(t, str, len);
 184                 ALLOC_GROW(ret, nr + 2, alloc);
 185                 ret[nr++] = t;
 186                 str += len;
 187                 slen -= len;
 188         }
 189         ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 190         ret[nr] = NULL;
 191         return ret;
 192 }
 193
 194 void strbuf_add_separated_string_list(struct strbuf *str,
 195                                       const char *sep,
 196                                       struct string_list *slist)
 197 {
 198         struct string_list_item *item;
 199         int sep_needed = 0;
 200
 201         for_each_string_list_item(item, slist) {
 202                 if (sep_needed)
 203                         strbuf_addstr(str, sep);
 204                 strbuf_addstr(str, item->string);
 205                 sep_needed = 1;
 206         }
 207 }
 208
 209 void strbuf_list_free(struct strbuf **sbs)
 210 {
 211         struct strbuf **s = sbs;
 212
 213         if (!s)
 214                 return;
 215         while (*s) {
 216                 strbuf_release(*s);
 217                 free(*s++);
 218         }
 219         free(sbs);
 220 }
 221
 222 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 223 {
 224         size_t len = a->len < b->len ? a->len: b->len;
 225         int cmp = memcmp(a->buf, b->buf, len);
 226         if (cmp)
 227                 return cmp;
 228         return a->len < b->len ? -1: a->len != b->len;
 229 }
 230
 231 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 232                                    const void *data, size_t dlen)
 233 {
 234         if (unsigned_add_overflows(pos, len))
 235                 die("you want to use way too much memory");
 236         if (pos > sb->len)
 237                 die("`pos' is too far after the end of the buffer");
 238         if (pos + len > sb->len)
 239                 die("`pos + len' is too far after the end of the buffer");
 240
 241         if (dlen >= len)
 242                 strbuf_grow(sb, dlen - len);
 243         memmove(sb->buf + pos + dlen,
 244                         sb->buf + pos + len,
 245                         sb->len - pos - len);
 246         memcpy(sb->buf + pos, data, dlen);
 247         strbuf_setlen(sb, sb->len + dlen - len);
 248 }
 249
 250 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 251 {
 252         strbuf_splice(sb, pos, 0, data, len);
 253 }
 254
 255 void strbuf_vinsertf(struct strbuf *sb, size_t pos, const char *fmt, va_list ap)
 256 {
 257         int len, len2;
 258         char save;
 259         va_list cp;
 260
 261         if (pos > sb->len)
 262                 die("`pos' is too far after the end of the buffer");
 263         va_copy(cp, ap);
 264         len = vsnprintf(sb->buf + sb->len, 0, fmt, cp);
 265         va_end(cp);
 266         if (len < 0)
 267                 BUG("your vsnprintf is broken (returned %d)", len);
 268         if (!len)
 269                 return; /* nothing to do */
 270         if (unsigned_add_overflows(sb->len, len))
 271                 die("you want to use way too much memory");
 272         strbuf_grow(sb, len);
 273         memmove(sb->buf + pos + len, sb->buf + pos, sb->len - pos);
 274         /* vsnprintf() will append a NUL, overwriting one of our characters */
 275         save = sb->buf[pos + len];
 276         len2 = vsnprintf(sb->buf + pos, len + 1, fmt, ap);
 277         sb->buf[pos + len] = save;
 278         if (len2 != len)
 279                 BUG("your vsnprintf is broken (returns inconsistent lengths)");
 280         strbuf_setlen(sb, sb->len + len);
 281 }
 282
 283 void strbuf_insertf(struct strbuf *sb, size_t pos, const char *fmt, ...)
 284 {
 285         va_list ap;
 286         va_start(ap, fmt);
 287         strbuf_vinsertf(sb, pos, fmt, ap);
 288         va_end(ap);
 289 }
 290
 291 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 292 {
 293         strbuf_splice(sb, pos, len, "", 0);
 294 }
 295
 296 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 297 {
 298         strbuf_grow(sb, len);
 299         memcpy(sb->buf + sb->len, data, len);
 300         strbuf_setlen(sb, sb->len + len);
 301 }
 302
 303 void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
 304 {
 305         strbuf_grow(sb, sb2->len);
 306         memcpy(sb->buf + sb->len, sb2->buf, sb2->len);
 307         strbuf_setlen(sb, sb->len + sb2->len);
 308 }
 309
 310 const char *strbuf_join_argv(struct strbuf *buf,
 311                              int argc, const char **argv, char delim)
 312 {
 313         if (!argc)
 314                 return buf->buf;
 315
 316         strbuf_addstr(buf, *argv);
 317         while (--argc) {
 318                 strbuf_addch(buf, delim);
 319                 strbuf_addstr(buf, *(++argv));
 320         }
 321
 322         return buf->buf;
 323 }
 324
 325 void strbuf_addchars(struct strbuf *sb, int c, size_t n)
 326 {
 327         strbuf_grow(sb, n);
 328         memset(sb->buf + sb->len, c, n);
 329         strbuf_setlen(sb, sb->len + n);
 330 }
 331
 332 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 333 {
 334         va_list ap;
 335         va_start(ap, fmt);
 336         strbuf_vaddf(sb, fmt, ap);
 337         va_end(ap);
 338 }
 339
 340 static void add_lines(struct strbuf *out,
 341                         const char *prefix1,
 342                         const char *prefix2,
 343                         const char *buf, size_t size)
 344 {
 345         while (size) {
 346                 const char *prefix;
 347                 const char *next = memchr(buf, '\n', size);
 348                 next = next ? (next + 1) : (buf + size);
 349
 350                 prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
 351                           ? prefix2 : prefix1);
 352                 strbuf_addstr(out, prefix);
 353                 strbuf_add(out, buf, next - buf);
 354                 size -= next - buf;
 355                 buf = next;
 356         }
 357         strbuf_complete_line(out);
 358 }
 359
 360 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 361 {
 362         static char prefix1[3];
 363         static char prefix2[2];
 364
 365         if (prefix1[0] != comment_line_char) {
 366                 xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
 367                 xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
 368         }
 369         add_lines(out, prefix1, prefix2, buf, size);
 370 }
 371
 372 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 373 {
 374         va_list params;
 375         struct strbuf buf = STRBUF_INIT;
 376         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 377
 378         va_start(params, fmt);
 379         strbuf_vaddf(&buf, fmt, params);
 380         va_end(params);
 381
 382         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 383         if (incomplete_line)
 384                 sb->buf[--sb->len] = '\0';
 385
 386         strbuf_release(&buf);
 387 }
 388
 389 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 390 {
 391         int len;
 392         va_list cp;
 393
 394         if (!strbuf_avail(sb))
 395                 strbuf_grow(sb, 64);
 396         va_copy(cp, ap);
 397         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 398         va_end(cp);
 399         if (len < 0)
 400                 BUG("your vsnprintf is broken (returned %d)", len);
 401         if (len > strbuf_avail(sb)) {
 402                 strbuf_grow(sb, len);
 403                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 404                 if (len > strbuf_avail(sb))
 405                         BUG("your vsnprintf is broken (insatiable)");
 406         }
 407         strbuf_setlen(sb, sb->len + len);
 408 }
 409
 410 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 411                    void *context)
 412 {
 413         for (;;) {
 414                 const char *percent;
 415                 size_t consumed;
 416
 417                 percent = strchrnul(format, '%');
 418                 strbuf_add(sb, format, percent - format);
 419                 if (!*percent)
 420                         break;
 421                 format = percent + 1;
 422
 423                 if (*format == '%') {
 424                         strbuf_addch(sb, '%');
 425                         format++;
 426                         continue;
 427                 }
 428
 429                 consumed = fn(sb, format, context);
 430                 if (consumed)
 431                         format += consumed;
 432                 else
 433                         strbuf_addch(sb, '%');
 434         }
 435 }
 436
 437 size_t strbuf_expand_literal_cb(struct strbuf *sb,
 438                                 const char *placeholder,
 439                                 void *context UNUSED)
 440 {
 441         int ch;
 442
 443         switch (placeholder[0]) {
 444         case 'n':               /* newline */
 445                 strbuf_addch(sb, '\n');
 446                 return 1;
 447         case 'x':
 448                 /* %x00 == NUL, %x0a == LF, etc. */
 449                 ch = hex2chr(placeholder + 1);
 450                 if (ch < 0)
 451                         return 0;
 452                 strbuf_addch(sb, ch);
 453                 return 3;
 454         }
 455         return 0;
 456 }
 457
 458 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 459                 void *context)
 460 {
 461         struct strbuf_expand_dict_entry *e = context;
 462         size_t len;
 463
 464         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 465                 if (!strncmp(placeholder, e->placeholder, len)) {
 466                         if (e->value)
 467                                 strbuf_addstr(sb, e->value);
 468                         return len;
 469                 }
 470         }
 471         return 0;
 472 }
 473
 474 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 475 {
 476         size_t i, len = src->len;
 477
 478         for (i = 0; i < len; i++) {
 479                 if (src->buf[i] == '%')
 480                         strbuf_addch(dst, '%');
 481                 strbuf_addch(dst, src->buf[i]);
 482         }
 483 }
 484
 485 #define URL_UNSAFE_CHARS " <>\"%{}|\\^`:?#[]@!$&'()*+,;="
 486
 487 void strbuf_add_percentencode(struct strbuf *dst, const char *src, int flags)
 488 {
 489         size_t i, len = strlen(src);
 490
 491         for (i = 0; i < len; i++) {
 492                 unsigned char ch = src[i];
 493                 if (ch <= 0x1F || ch >= 0x7F ||
 494                     (ch == '/' && (flags & STRBUF_ENCODE_SLASH)) ||
 495                     strchr(URL_UNSAFE_CHARS, ch))
 496                         strbuf_addf(dst, "%%%02X", (unsigned char)ch);
 497                 else
 498                         strbuf_addch(dst, ch);
 499         }
 500 }
 501
 502 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 503 {
 504         size_t res;
 505         size_t oldalloc = sb->alloc;
 506
 507         strbuf_grow(sb, size);
 508         res = fread(sb->buf + sb->len, 1, size, f);
 509         if (res > 0)
 510                 strbuf_setlen(sb, sb->len + res);
 511         else if (oldalloc == 0)
 512                 strbuf_release(sb);
 513         return res;
 514 }
 515
 516 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 517 {
 518         size_t oldlen = sb->len;
 519         size_t oldalloc = sb->alloc;
 520
 521         strbuf_grow(sb, hint ? hint : 8192);
 522         for (;;) {
 523                 ssize_t want = sb->alloc - sb->len - 1;
 524                 ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
 525
 526                 if (got < 0) {
 527                         if (oldalloc == 0)
 528                                 strbuf_release(sb);
 529                         else
 530                                 strbuf_setlen(sb, oldlen);
 531                         return -1;
 532                 }
 533                 sb->len += got;
 534                 if (got < want)
 535                         break;
 536                 strbuf_grow(sb, 8192);
 537         }
 538
 539         sb->buf[sb->len] = '\0';
 540         return sb->len - oldlen;
 541 }
 542
 543 ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
 544 {
 545         size_t oldalloc = sb->alloc;
 546         ssize_t cnt;
 547
 548         strbuf_grow(sb, hint ? hint : 8192);
 549         cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 550         if (cnt > 0)
 551                 strbuf_setlen(sb, sb->len + cnt);
 552         else if (oldalloc == 0)
 553                 strbuf_release(sb);
 554         return cnt;
 555 }
 556
 557 ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 558 {
 559         return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 560 }
 561
 562 #define STRBUF_MAXLINK (2*PATH_MAX)
 563
 564 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 565 {
 566         size_t oldalloc = sb->alloc;
 567
 568         if (hint < 32)
 569                 hint = 32;
 570
 571         while (hint < STRBUF_MAXLINK) {
 572                 ssize_t len;
 573
 574                 strbuf_grow(sb, hint);
 575                 len = readlink(path, sb->buf, hint);
 576                 if (len < 0) {
 577                         if (errno != ERANGE)
 578                                 break;
 579                 } else if (len < hint) {
 580                         strbuf_setlen(sb, len);
 581                         return 0;
 582                 }
 583
 584                 /* .. the buffer was too small - try again */
 585                 hint *= 2;
 586         }
 587         if (oldalloc == 0)
 588                 strbuf_release(sb);
 589         return -1;
 590 }
 591
 592 int strbuf_getcwd(struct strbuf *sb)
 593 {
 594         size_t oldalloc = sb->alloc;
 595         size_t guessed_len = 128;
 596
 597         for (;; guessed_len *= 2) {
 598                 strbuf_grow(sb, guessed_len);
 599                 if (getcwd(sb->buf, sb->alloc)) {
 600                         strbuf_setlen(sb, strlen(sb->buf));
 601                         return 0;
 602                 }
 603
 604                 /*
 605                  * If getcwd(3) is implemented as a syscall that falls
 606                  * back to a regular lookup using readdir(3) etc. then
 607                  * we may be able to avoid EACCES by providing enough
 608                  * space to the syscall as it's not necessarily bound
 609                  * to the same restrictions as the fallback.
 610                  */
 611                 if (errno == EACCES && guessed_len < PATH_MAX)
 612                         continue;
 613
 614                 if (errno != ERANGE)
 615                         break;
 616         }
 617         if (oldalloc == 0)
 618                 strbuf_release(sb);
 619         else
 620                 strbuf_reset(sb);
 621         return -1;
 622 }
 623
 624 #ifdef HAVE_GETDELIM
 625 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 626 {
 627         ssize_t r;
 628
 629         if (feof(fp))
 630                 return EOF;
 631
 632         strbuf_reset(sb);
 633
 634         /* Translate slopbuf to NULL, as we cannot call realloc on it */
 635         if (!sb->alloc)
 636                 sb->buf = NULL;
 637         errno = 0;
 638         r = getdelim(&sb->buf, &sb->alloc, term, fp);
 639
 640         if (r > 0) {
 641                 sb->len = r;
 642                 return 0;
 643         }
 644         assert(r == -1);
 645
 646         /*
 647          * Normally we would have called xrealloc, which will try to free
 648          * memory and recover. But we have no way to tell getdelim() to do so.
 649          * Worse, we cannot try to recover ENOMEM ourselves, because we have
 650          * no idea how many bytes were read by getdelim.
 651          *
 652          * Dying here is reasonable. It mirrors what xrealloc would do on
 653          * catastrophic memory failure. We skip the opportunity to free pack
 654          * memory and retry, but that's unlikely to help for a malloc small
 655          * enough to hold a single line of input, anyway.
 656          */
 657         if (errno == ENOMEM)
 658                 die("Out of memory, getdelim failed");
 659
 660         /*
 661          * Restore strbuf invariants; if getdelim left us with a NULL pointer,
 662          * we can just re-init, but otherwise we should make sure that our
 663          * length is empty, and that the result is NUL-terminated.
 664          */
 665         if (!sb->buf)
 666                 strbuf_init(sb, 0);
 667         else
 668                 strbuf_reset(sb);
 669         return EOF;
 670 }
 671 #else
 672 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 673 {
 674         int ch;
 675
 676         if (feof(fp))
 677                 return EOF;
 678
 679         strbuf_reset(sb);
 680         flockfile(fp);
 681         while ((ch = getc_unlocked(fp)) != EOF) {
 682                 if (!strbuf_avail(sb))
 683                         strbuf_grow(sb, 1);
 684                 sb->buf[sb->len++] = ch;
 685                 if (ch == term)
 686                         break;
 687         }
 688         funlockfile(fp);
 689         if (ch == EOF && sb->len == 0)
 690                 return EOF;
 691
 692         sb->buf[sb->len] = '\0';
 693         return 0;
 694 }
 695 #endif
 696
 697 int strbuf_appendwholeline(struct strbuf *sb, FILE *fp, int term)
 698 {
 699         struct strbuf line = STRBUF_INIT;
 700         if (strbuf_getwholeline(&line, fp, term))
 701                 return EOF;
 702         strbuf_addbuf(sb, &line);
 703         strbuf_release(&line);
 704         return 0;
 705 }
 706
 707 static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 708 {
 709         if (strbuf_getwholeline(sb, fp, term))
 710                 return EOF;
 711         if (sb->buf[sb->len - 1] == term)
 712                 strbuf_setlen(sb, sb->len - 1);
 713         return 0;
 714 }
 715
 716 int strbuf_getline(struct strbuf *sb, FILE *fp)
 717 {
 718         if (strbuf_getwholeline(sb, fp, '\n'))
 719                 return EOF;
 720         if (sb->buf[sb->len - 1] == '\n') {
 721                 strbuf_setlen(sb, sb->len - 1);
 722                 if (sb->len && sb->buf[sb->len - 1] == '\r')
 723                         strbuf_setlen(sb, sb->len - 1);
 724         }
 725         return 0;
 726 }
 727
 728 int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 729 {
 730         return strbuf_getdelim(sb, fp, '\n');
 731 }
 732
 733 int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 734 {
 735         return strbuf_getdelim(sb, fp, '\0');
 736 }
 737
 738 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 739 {
 740         strbuf_reset(sb);
 741
 742         while (1) {
 743                 char ch;
 744                 ssize_t len = xread(fd, &ch, 1);
 745                 if (len <= 0)
 746                         return EOF;
 747                 strbuf_addch(sb, ch);
 748                 if (ch == term)
 749                         break;
 750         }
 751         return 0;
 752 }
 753
 754 ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 755 {
 756         int fd;
 757         ssize_t len;
 758         int saved_errno;
 759
 760         fd = open(path, O_RDONLY);
 761         if (fd < 0)
 762                 return -1;
 763         len = strbuf_read(sb, fd, hint);
 764         saved_errno = errno;
 765         close(fd);
 766         if (len < 0) {
 767                 errno = saved_errno;
 768                 return -1;
 769         }
 770
 771         return len;
 772 }
 773
 774 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 775                       const char *buf, size_t size)
 776 {
 777         add_lines(out, prefix, NULL, buf, size);
 778 }
 779
 780 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 781 {
 782         while (*s) {
 783                 size_t len = strcspn(s, "\"<>&");
 784                 strbuf_add(buf, s, len);
 785                 s += len;
 786                 switch (*s) {
 787                 case '"':
 788                         strbuf_addstr(buf, "&quot;");
 789                         break;
 790                 case '<':
 791                         strbuf_addstr(buf, "&lt;");
 792                         break;
 793                 case '>':
 794                         strbuf_addstr(buf, "&gt;");
 795                         break;
 796                 case '&':
 797                         strbuf_addstr(buf, "&amp;");
 798                         break;
 799                 case 0:
 800                         return;
 801                 }
 802                 s++;
 803         }
 804 }
 805
 806 int is_rfc3986_reserved_or_unreserved(char ch)
 807 {
 808         if (is_rfc3986_unreserved(ch))
 809                 return 1;
 810         switch (ch) {
 811                 case '!': case '*': case '\'': case '(': case ')': case ';':
 812                 case ':': case '@': case '&': case '=': case '+': case '$':
 813                 case ',': case '/': case '?': case '#': case '[': case ']':
 814                         return 1;
 815         }
 816         return 0;
 817 }
 818
 819 int is_rfc3986_unreserved(char ch)
 820 {
 821         return isalnum(ch) ||
 822                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 823 }
 824
 825 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 826                                  char_predicate allow_unencoded_fn)
 827 {
 828         strbuf_grow(sb, len);
 829         while (len--) {
 830                 char ch = *s++;
 831                 if (allow_unencoded_fn(ch))
 832                         strbuf_addch(sb, ch);
 833                 else
 834                         strbuf_addf(sb, "%%%02x", (unsigned char)ch);
 835         }
 836 }
 837
 838 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 839                              char_predicate allow_unencoded_fn)
 840 {
 841         strbuf_add_urlencode(sb, s, strlen(s), allow_unencoded_fn);
 842 }
 843
 844 static void strbuf_humanise(struct strbuf *buf, off_t bytes,
 845                                  int humanise_rate)
 846 {
 847         if (bytes > 1 << 30) {
 848                 strbuf_addf(buf,
 849                                 humanise_rate == 0 ?
 850                                         /* TRANSLATORS: IEC 80000-13:2008 gibibyte */
 851                                         _("%u.%2.2u GiB") :
 852                                         /* TRANSLATORS: IEC 80000-13:2008 gibibyte/second */
 853                                         _("%u.%2.2u GiB/s"),
 854                             (unsigned)(bytes >> 30),
 855                             (unsigned)(bytes & ((1 << 30) - 1)) / 10737419);
 856         } else if (bytes > 1 << 20) {
 857                 unsigned x = bytes + 5243;  /* for rounding */
 858                 strbuf_addf(buf,
 859                                 humanise_rate == 0 ?
 860                                         /* TRANSLATORS: IEC 80000-13:2008 mebibyte */
 861                                         _("%u.%2.2u MiB") :
 862                                         /* TRANSLATORS: IEC 80000-13:2008 mebibyte/second */
 863                                         _("%u.%2.2u MiB/s"),
 864                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 865         } else if (bytes > 1 << 10) {
 866                 unsigned x = bytes + 5;  /* for rounding */
 867                 strbuf_addf(buf,
 868                                 humanise_rate == 0 ?
 869                                         /* TRANSLATORS: IEC 80000-13:2008 kibibyte */
 870                                         _("%u.%2.2u KiB") :
 871                                         /* TRANSLATORS: IEC 80000-13:2008 kibibyte/second */
 872                                         _("%u.%2.2u KiB/s"),
 873                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 874         } else {
 875                 strbuf_addf(buf,
 876                                 humanise_rate == 0 ?
 877                                         /* TRANSLATORS: IEC 80000-13:2008 byte */
 878                                         Q_("%u byte", "%u bytes", bytes) :
 879                                         /* TRANSLATORS: IEC 80000-13:2008 byte/second */
 880                                         Q_("%u byte/s", "%u bytes/s", bytes),
 881                                 (unsigned)bytes);
 882         }
 883 }
 884
 885 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 886 {
 887         strbuf_humanise(buf, bytes, 0);
 888 }
 889
 890 void strbuf_humanise_rate(struct strbuf *buf, off_t bytes)
 891 {
 892         strbuf_humanise(buf, bytes, 1);
 893 }
 894
 895 void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 896 {
 897         if (!*path)
 898                 die("The empty string is not a valid path");
 899         if (!is_absolute_path(path)) {
 900                 struct stat cwd_stat, pwd_stat;
 901                 size_t orig_len = sb->len;
 902                 char *cwd = xgetcwd();
 903                 char *pwd = getenv("PWD");
 904                 if (pwd && strcmp(pwd, cwd) &&
 905                     !stat(cwd, &cwd_stat) &&
 906                     (cwd_stat.st_dev || cwd_stat.st_ino) &&
 907                     !stat(pwd, &pwd_stat) &&
 908                     pwd_stat.st_dev == cwd_stat.st_dev &&
 909                     pwd_stat.st_ino == cwd_stat.st_ino)
 910                         strbuf_addstr(sb, pwd);
 911                 else
 912                         strbuf_addstr(sb, cwd);
 913                 if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 914                         strbuf_addch(sb, '/');
 915                 free(cwd);
 916         }
 917         strbuf_addstr(sb, path);
 918 }
 919
 920 void strbuf_add_real_path(struct strbuf *sb, const char *path)
 921 {
 922         if (sb->len) {
 923                 struct strbuf resolved = STRBUF_INIT;
 924                 strbuf_realpath(&resolved, path, 1);
 925                 strbuf_addbuf(sb, &resolved);
 926                 strbuf_release(&resolved);
 927         } else
 928                 strbuf_realpath(sb, path, 1);
 929 }
 930
 931 int printf_ln(const char *fmt, ...)
 932 {
 933         int ret;
 934         va_list ap;
 935         va_start(ap, fmt);
 936         ret = vprintf(fmt, ap);
 937         va_end(ap);
 938         if (ret < 0 || putchar('\n') == EOF)
 939                 return -1;
 940         return ret + 1;
 941 }
 942
 943 int fprintf_ln(FILE *fp, const char *fmt, ...)
 944 {
 945         int ret;
 946         va_list ap;
 947         va_start(ap, fmt);
 948         ret = vfprintf(fp, fmt, ap);
 949         va_end(ap);
 950         if (ret < 0 || putc('\n', fp) == EOF)
 951                 return -1;
 952         return ret + 1;
 953 }
 954
 955 char *xstrdup_tolower(const char *string)
 956 {
 957         char *result;
 958         size_t len, i;
 959
 960         len = strlen(string);
 961         result = xmallocz(len);
 962         for (i = 0; i < len; i++)
 963                 result[i] = tolower(string[i]);
 964         return result;
 965 }
 966
 967 char *xstrdup_toupper(const char *string)
 968 {
 969         char *result;
 970         size_t len, i;
 971
 972         len = strlen(string);
 973         result = xmallocz(len);
 974         for (i = 0; i < len; i++)
 975                 result[i] = toupper(string[i]);
 976         return result;
 977 }
 978
 979 char *xstrvfmt(const char *fmt, va_list ap)
 980 {
 981         struct strbuf buf = STRBUF_INIT;
 982         strbuf_vaddf(&buf, fmt, ap);
 983         return strbuf_detach(&buf, NULL);
 984 }
 985
 986 char *xstrfmt(const char *fmt, ...)
 987 {
 988         va_list ap;
 989         char *ret;
 990
 991         va_start(ap, fmt);
 992         ret = xstrvfmt(fmt, ap);
 993         va_end(ap);
 994
 995         return ret;
 996 }
 997
 998 void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 999                      int tz_offset, int suppress_tz_name)
1000 {
1001         struct strbuf munged_fmt = STRBUF_INIT;
1002         size_t hint = 128;
1003         size_t len;
1004
1005         if (!*fmt)
1006                 return;
1007
1008         /*
1009          * There is no portable way to pass timezone information to
1010          * strftime, so we handle %z and %Z here. Likewise '%s', because
1011          * going back to an epoch time requires knowing the zone.
1012          *
1013          * Note that tz_offset is in the "[-+]HHMM" decimal form; this is what
1014          * we want for %z, but the computation for %s has to convert to number
1015          * of seconds.
1016          */
1017         for (;;) {
1018                 const char *percent = strchrnul(fmt, '%');
1019                 strbuf_add(&munged_fmt, fmt, percent - fmt);
1020                 if (!*percent)
1021                         break;
1022                 fmt = percent + 1;
1023                 switch (*fmt) {
1024                 case '%':
1025                         strbuf_addstr(&munged_fmt, "%%");
1026                         fmt++;
1027                         break;
1028                 case 's':
1029                         strbuf_addf(&munged_fmt, "%"PRItime,
1030                                     (timestamp_t)tm_to_time_t(tm) -
1031                                     3600 * (tz_offset / 100) -
1032                                     60 * (tz_offset % 100));
1033                         fmt++;
1034                         break;
1035                 case 'z':
1036                         strbuf_addf(&munged_fmt, "%+05d", tz_offset);
1037                         fmt++;
1038                         break;
1039                 case 'Z':
1040                         if (suppress_tz_name) {
1041                                 fmt++;
1042                                 break;
1043                         }
1044                         /* FALLTHROUGH */
1045                 default:
1046                         strbuf_addch(&munged_fmt, '%');
1047                 }
1048         }
1049         fmt = munged_fmt.buf;
1050
1051         strbuf_grow(sb, hint);
1052         len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
1053
1054         if (!len) {
1055                 /*
1056                  * strftime reports "0" if it could not fit the result in the buffer.
1057                  * Unfortunately, it also reports "0" if the requested time string
1058                  * takes 0 bytes. So our strategy is to munge the format so that the
1059                  * output contains at least one character, and then drop the extra
1060                  * character before returning.
1061                  */
1062                 strbuf_addch(&munged_fmt, ' ');
1063                 while (!len) {
1064                         hint *= 2;
1065                         strbuf_grow(sb, hint);
1066                         len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
1067                                        munged_fmt.buf, tm);
1068                 }
1069                 len--; /* drop munged space */
1070         }
1071         strbuf_release(&munged_fmt);
1072         strbuf_setlen(sb, sb->len + len);
1073 }
1074
1075 void strbuf_repo_add_unique_abbrev(struct strbuf *sb, struct repository *repo,
1076                                    const struct object_id *oid, int abbrev_len)
1077 {
1078         int r;
1079         strbuf_grow(sb, GIT_MAX_HEXSZ + 1);
1080         r = repo_find_unique_abbrev_r(repo, sb->buf + sb->len, oid, abbrev_len);
1081         strbuf_setlen(sb, sb->len + r);
1082 }
1083
1084 void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
1085                               int abbrev_len)
1086 {
1087         strbuf_repo_add_unique_abbrev(sb, the_repository, oid, abbrev_len);
1088 }
1089
1090 /*
1091  * Returns the length of a line, without trailing spaces.
1092  *
1093  * If the line ends with newline, it will be removed too.
1094  */
1095 static size_t cleanup(char *line, size_t len)
1096 {
1097         while (len) {
1098                 unsigned char c = line[len - 1];
1099                 if (!isspace(c))
1100                         break;
1101                 len--;
1102         }
1103
1104         return len;
1105 }
1106
1107 /*
1108  * Remove empty lines from the beginning and end
1109  * and also trailing spaces from every line.
1110  *
1111  * Turn multiple consecutive empty lines between paragraphs
1112  * into just one empty line.
1113  *
1114  * If the input has only empty lines and spaces,
1115  * no output will be produced.
1116  *
1117  * If last line does not have a newline at the end, one is added.
1118  *
1119  * Enable skip_comments to skip every line starting with comment
1120  * character.
1121  */
1122 void strbuf_stripspace(struct strbuf *sb, int skip_comments)
1123 {
1124         size_t empties = 0;
1125         size_t i, j, len, newlen;
1126         char *eol;
1127
1128         /* We may have to add a newline. */
1129         strbuf_grow(sb, 1);
1130
1131         for (i = j = 0; i < sb->len; i += len, j += newlen) {
1132                 eol = memchr(sb->buf + i, '\n', sb->len - i);
1133                 len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
1134
1135                 if (skip_comments && len && sb->buf[i] == comment_line_char) {
1136                         newlen = 0;
1137                         continue;
1138                 }
1139                 newlen = cleanup(sb->buf + i, len);
1140
1141                 /* Not just an empty line? */
1142                 if (newlen) {
1143                         if (empties > 0 && j > 0)
1144                                 sb->buf[j++] = '\n';
1145                         empties = 0;
1146                         memmove(sb->buf + j, sb->buf + i, newlen);
1147                         sb->buf[newlen + j++] = '\n';
1148                 } else {
1149                         empties++;
1150                 }
1151         }
1152
1153         strbuf_setlen(sb, j);
1154 }
1155
1156 int strbuf_normalize_path(struct strbuf *src)
1157 {
1158         struct strbuf dst = STRBUF_INIT;
1159
1160         strbuf_grow(&dst, src->len);
1161         if (normalize_path_copy(dst.buf, src->buf) < 0) {
1162                 strbuf_release(&dst);
1163                 return -1;
1164         }
1165
1166         /*
1167          * normalize_path does not tell us the new length, so we have to
1168          * compute it by looking for the new NUL it placed
1169          */
1170         strbuf_setlen(&dst, strlen(dst.buf));
1171         strbuf_swap(src, &dst);
1172         strbuf_release(&dst);
1173         return 0;
1174 }
1175
1176 int strbuf_edit_interactively(struct strbuf *buffer, const char *path,
1177                               const char *const *env)
1178 {
1179         char *path2 = NULL;
1180         int fd, res = 0;
1181
1182         if (!is_absolute_path(path))
1183                 path = path2 = xstrdup(git_path("%s", path));
1184
1185         fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0666);
1186         if (fd < 0)
1187                 res = error_errno(_("could not open '%s' for writing"), path);
1188         else if (write_in_full(fd, buffer->buf, buffer->len) < 0) {
1189                 res = error_errno(_("could not write to '%s'"), path);
1190                 close(fd);
1191         } else if (close(fd) < 0)
1192                 res = error_errno(_("could not close '%s'"), path);
1193         else {
1194                 strbuf_reset(buffer);
1195                 if (launch_editor(path, buffer, env) < 0)
1196                         res = error_errno(_("could not edit '%s'"), path);
1197                 unlink(path);
1198         }
1199
1200         free(path2);
1201         return res;
1202 }
1203
1204 void strbuf_strip_file_from_path(struct strbuf *sb)
1205 {
1206         char *path_sep = find_last_dir_sep(sb->buf);
1207         strbuf_setlen(sb, path_sep ? path_sep - sb->buf + 1 : 0);
1208 }