strbuf.c

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