strbuf.c

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