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