strbuf.c

   1 #include "git-compat-util.h"
   2 #include "alloc.h"
   3 #include "hex.h"
   4 #include "refs.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 *prefix1,
 344                         const char *prefix2,
 345                         const char *buf, size_t size)
 346 {
 347         while (size) {
 348                 const char *prefix;
 349                 const char *next = memchr(buf, '\n', size);
 350                 next = next ? (next + 1) : (buf + size);
 351
 352                 prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
 353                           ? prefix2 : prefix1);
 354                 strbuf_addstr(out, prefix);
 355                 strbuf_add(out, buf, next - buf);
 356                 size -= next - buf;
 357                 buf = next;
 358         }
 359         strbuf_complete_line(out);
 360 }
 361
 362 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 363 {
 364         static char prefix1[3];
 365         static char prefix2[2];
 366
 367         if (prefix1[0] != comment_line_char) {
 368                 xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
 369                 xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
 370         }
 371         add_lines(out, prefix1, prefix2, buf, size);
 372 }
 373
 374 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 375 {
 376         va_list params;
 377         struct strbuf buf = STRBUF_INIT;
 378         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 379
 380         va_start(params, fmt);
 381         strbuf_vaddf(&buf, fmt, params);
 382         va_end(params);
 383
 384         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 385         if (incomplete_line)
 386                 sb->buf[--sb->len] = '\0';
 387
 388         strbuf_release(&buf);
 389 }
 390
 391 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 392 {
 393         int len;
 394         va_list cp;
 395
 396         if (!strbuf_avail(sb))
 397                 strbuf_grow(sb, 64);
 398         va_copy(cp, ap);
 399         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 400         va_end(cp);
 401         if (len < 0)
 402                 BUG("your vsnprintf is broken (returned %d)", len);
 403         if (len > strbuf_avail(sb)) {
 404                 strbuf_grow(sb, len);
 405                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 406                 if (len > strbuf_avail(sb))
 407                         BUG("your vsnprintf is broken (insatiable)");
 408         }
 409         strbuf_setlen(sb, sb->len + len);
 410 }
 411
 412 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 413                    void *context)
 414 {
 415         for (;;) {
 416                 const char *percent;
 417                 size_t consumed;
 418
 419                 percent = strchrnul(format, '%');
 420                 strbuf_add(sb, format, percent - format);
 421                 if (!*percent)
 422                         break;
 423                 format = percent + 1;
 424
 425                 if (*format == '%') {
 426                         strbuf_addch(sb, '%');
 427                         format++;
 428                         continue;
 429                 }
 430
 431                 consumed = fn(sb, format, context);
 432                 if (consumed)
 433                         format += consumed;
 434                 else
 435                         strbuf_addch(sb, '%');
 436         }
 437 }
 438
 439 size_t strbuf_expand_literal_cb(struct strbuf *sb,
 440                                 const char *placeholder,
 441                                 void *context UNUSED)
 442 {
 443         int ch;
 444
 445         switch (placeholder[0]) {
 446         case 'n':               /* newline */
 447                 strbuf_addch(sb, '\n');
 448                 return 1;
 449         case 'x':
 450                 /* %x00 == NUL, %x0a == LF, etc. */
 451                 ch = hex2chr(placeholder + 1);
 452                 if (ch < 0)
 453                         return 0;
 454                 strbuf_addch(sb, ch);
 455                 return 3;
 456         }
 457         return 0;
 458 }
 459
 460 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 461                 void *context)
 462 {
 463         struct strbuf_expand_dict_entry *e = context;
 464         size_t len;
 465
 466         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 467                 if (!strncmp(placeholder, e->placeholder, len)) {
 468                         if (e->value)
 469                                 strbuf_addstr(sb, e->value);
 470                         return len;
 471                 }
 472         }
 473         return 0;
 474 }
 475
 476 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 477 {
 478         size_t i, len = src->len;
 479
 480         for (i = 0; i < len; i++) {
 481                 if (src->buf[i] == '%')
 482                         strbuf_addch(dst, '%');
 483                 strbuf_addch(dst, src->buf[i]);
 484         }
 485 }
 486
 487 #define URL_UNSAFE_CHARS " <>\"%{}|\\^`:?#[]@!$&'()*+,;="
 488
 489 void strbuf_add_percentencode(struct strbuf *dst, const char *src, int flags)
 490 {
 491         size_t i, len = strlen(src);
 492
 493         for (i = 0; i < len; i++) {
 494                 unsigned char ch = src[i];
 495                 if (ch <= 0x1F || ch >= 0x7F ||
 496                     (ch == '/' && (flags & STRBUF_ENCODE_SLASH)) ||
 497                     strchr(URL_UNSAFE_CHARS, ch))
 498                         strbuf_addf(dst, "%%%02X", (unsigned char)ch);
 499                 else
 500                         strbuf_addch(dst, ch);
 501         }
 502 }
 503
 504 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 505 {
 506         size_t res;
 507         size_t oldalloc = sb->alloc;
 508
 509         strbuf_grow(sb, size);
 510         res = fread(sb->buf + sb->len, 1, size, f);
 511         if (res > 0)
 512                 strbuf_setlen(sb, sb->len + res);
 513         else if (oldalloc == 0)
 514                 strbuf_release(sb);
 515         return res;
 516 }
 517
 518 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 519 {
 520         size_t oldlen = sb->len;
 521         size_t oldalloc = sb->alloc;
 522
 523         strbuf_grow(sb, hint ? hint : 8192);
 524         for (;;) {
 525                 ssize_t want = sb->alloc - sb->len - 1;
 526                 ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
 527
 528                 if (got < 0) {
 529                         if (oldalloc == 0)
 530                                 strbuf_release(sb);
 531                         else
 532                                 strbuf_setlen(sb, oldlen);
 533                         return -1;
 534                 }
 535                 sb->len += got;
 536                 if (got < want)
 537                         break;
 538                 strbuf_grow(sb, 8192);
 539         }
 540
 541         sb->buf[sb->len] = '\0';
 542         return sb->len - oldlen;
 543 }
 544
 545 ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
 546 {
 547         size_t oldalloc = sb->alloc;
 548         ssize_t cnt;
 549
 550         strbuf_grow(sb, hint ? hint : 8192);
 551         cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 552         if (cnt > 0)
 553                 strbuf_setlen(sb, sb->len + cnt);
 554         else if (oldalloc == 0)
 555                 strbuf_release(sb);
 556         return cnt;
 557 }
 558
 559 ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 560 {
 561         return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 562 }
 563
 564 #define STRBUF_MAXLINK (2*PATH_MAX)
 565
 566 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 567 {
 568         size_t oldalloc = sb->alloc;
 569
 570         if (hint < 32)
 571                 hint = 32;
 572
 573         while (hint < STRBUF_MAXLINK) {
 574                 ssize_t len;
 575
 576                 strbuf_grow(sb, hint);
 577                 len = readlink(path, sb->buf, hint);
 578                 if (len < 0) {
 579                         if (errno != ERANGE)
 580                                 break;
 581                 } else if (len < hint) {
 582                         strbuf_setlen(sb, len);
 583                         return 0;
 584                 }
 585
 586                 /* .. the buffer was too small - try again */
 587                 hint *= 2;
 588         }
 589         if (oldalloc == 0)
 590                 strbuf_release(sb);
 591         return -1;
 592 }
 593
 594 int strbuf_getcwd(struct strbuf *sb)
 595 {
 596         size_t oldalloc = sb->alloc;
 597         size_t guessed_len = 128;
 598
 599         for (;; guessed_len *= 2) {
 600                 strbuf_grow(sb, guessed_len);
 601                 if (getcwd(sb->buf, sb->alloc)) {
 602                         strbuf_setlen(sb, strlen(sb->buf));
 603                         return 0;
 604                 }
 605
 606                 /*
 607                  * If getcwd(3) is implemented as a syscall that falls
 608                  * back to a regular lookup using readdir(3) etc. then
 609                  * we may be able to avoid EACCES by providing enough
 610                  * space to the syscall as it's not necessarily bound
 611                  * to the same restrictions as the fallback.
 612                  */
 613                 if (errno == EACCES && guessed_len < PATH_MAX)
 614                         continue;
 615
 616                 if (errno != ERANGE)
 617                         break;
 618         }
 619         if (oldalloc == 0)
 620                 strbuf_release(sb);
 621         else
 622                 strbuf_reset(sb);
 623         return -1;
 624 }
 625
 626 #ifdef HAVE_GETDELIM
 627 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 628 {
 629         ssize_t r;
 630
 631         if (feof(fp))
 632                 return EOF;
 633
 634         strbuf_reset(sb);
 635
 636         /* Translate slopbuf to NULL, as we cannot call realloc on it */
 637         if (!sb->alloc)
 638                 sb->buf = NULL;
 639         errno = 0;
 640         r = getdelim(&sb->buf, &sb->alloc, term, fp);
 641
 642         if (r > 0) {
 643                 sb->len = r;
 644                 return 0;
 645         }
 646         assert(r == -1);
 647
 648         /*
 649          * Normally we would have called xrealloc, which will try to free
 650          * memory and recover. But we have no way to tell getdelim() to do so.
 651          * Worse, we cannot try to recover ENOMEM ourselves, because we have
 652          * no idea how many bytes were read by getdelim.
 653          *
 654          * Dying here is reasonable. It mirrors what xrealloc would do on
 655          * catastrophic memory failure. We skip the opportunity to free pack
 656          * memory and retry, but that's unlikely to help for a malloc small
 657          * enough to hold a single line of input, anyway.
 658          */
 659         if (errno == ENOMEM)
 660                 die("Out of memory, getdelim failed");
 661
 662         /*
 663          * Restore strbuf invariants; if getdelim left us with a NULL pointer,
 664          * we can just re-init, but otherwise we should make sure that our
 665          * length is empty, and that the result is NUL-terminated.
 666          */
 667         if (!sb->buf)
 668                 strbuf_init(sb, 0);
 669         else
 670                 strbuf_reset(sb);
 671         return EOF;
 672 }
 673 #else
 674 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 675 {
 676         int ch;
 677
 678         if (feof(fp))
 679                 return EOF;
 680
 681         strbuf_reset(sb);
 682         flockfile(fp);
 683         while ((ch = getc_unlocked(fp)) != EOF) {
 684                 if (!strbuf_avail(sb))
 685                         strbuf_grow(sb, 1);
 686                 sb->buf[sb->len++] = ch;
 687                 if (ch == term)
 688                         break;
 689         }
 690         funlockfile(fp);
 691         if (ch == EOF && sb->len == 0)
 692                 return EOF;
 693
 694         sb->buf[sb->len] = '\0';
 695         return 0;
 696 }
 697 #endif
 698
 699 int strbuf_appendwholeline(struct strbuf *sb, FILE *fp, int term)
 700 {
 701         struct strbuf line = STRBUF_INIT;
 702         if (strbuf_getwholeline(&line, fp, term))
 703                 return EOF;
 704         strbuf_addbuf(sb, &line);
 705         strbuf_release(&line);
 706         return 0;
 707 }
 708
 709 static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 710 {
 711         if (strbuf_getwholeline(sb, fp, term))
 712                 return EOF;
 713         if (sb->buf[sb->len - 1] == term)
 714                 strbuf_setlen(sb, sb->len - 1);
 715         return 0;
 716 }
 717
 718 int strbuf_getline(struct strbuf *sb, FILE *fp)
 719 {
 720         if (strbuf_getwholeline(sb, fp, '\n'))
 721                 return EOF;
 722         if (sb->buf[sb->len - 1] == '\n') {
 723                 strbuf_setlen(sb, sb->len - 1);
 724                 if (sb->len && sb->buf[sb->len - 1] == '\r')
 725                         strbuf_setlen(sb, sb->len - 1);
 726         }
 727         return 0;
 728 }
 729
 730 int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 731 {
 732         return strbuf_getdelim(sb, fp, '\n');
 733 }
 734
 735 int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 736 {
 737         return strbuf_getdelim(sb, fp, '\0');
 738 }
 739
 740 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 741 {
 742         strbuf_reset(sb);
 743
 744         while (1) {
 745                 char ch;
 746                 ssize_t len = xread(fd, &ch, 1);
 747                 if (len <= 0)
 748                         return EOF;
 749                 strbuf_addch(sb, ch);
 750                 if (ch == term)
 751                         break;
 752         }
 753         return 0;
 754 }
 755
 756 ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 757 {
 758         int fd;
 759         ssize_t len;
 760         int saved_errno;
 761
 762         fd = open(path, O_RDONLY);
 763         if (fd < 0)
 764                 return -1;
 765         len = strbuf_read(sb, fd, hint);
 766         saved_errno = errno;
 767         close(fd);
 768         if (len < 0) {
 769                 errno = saved_errno;
 770                 return -1;
 771         }
 772
 773         return len;
 774 }
 775
 776 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 777                       const char *buf, size_t size)
 778 {
 779         add_lines(out, prefix, NULL, buf, size);
 780 }
 781
 782 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 783 {
 784         while (*s) {
 785                 size_t len = strcspn(s, "\"<>&");
 786                 strbuf_add(buf, s, len);
 787                 s += len;
 788                 switch (*s) {
 789                 case '"':
 790                         strbuf_addstr(buf, "&quot;");
 791                         break;
 792                 case '<':
 793                         strbuf_addstr(buf, "&lt;");
 794                         break;
 795                 case '>':
 796                         strbuf_addstr(buf, "&gt;");
 797                         break;
 798                 case '&':
 799                         strbuf_addstr(buf, "&amp;");
 800                         break;
 801                 case 0:
 802                         return;
 803                 }
 804                 s++;
 805         }
 806 }
 807
 808 int is_rfc3986_reserved_or_unreserved(char ch)
 809 {
 810         if (is_rfc3986_unreserved(ch))
 811                 return 1;
 812         switch (ch) {
 813                 case '!': case '*': case '\'': case '(': case ')': case ';':
 814                 case ':': case '@': case '&': case '=': case '+': case '$':
 815                 case ',': case '/': case '?': case '#': case '[': case ']':
 816                         return 1;
 817         }
 818         return 0;
 819 }
 820
 821 int is_rfc3986_unreserved(char ch)
 822 {
 823         return isalnum(ch) ||
 824                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 825 }
 826
 827 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 828                                  char_predicate allow_unencoded_fn)
 829 {
 830         strbuf_grow(sb, len);
 831         while (len--) {
 832                 char ch = *s++;
 833                 if (allow_unencoded_fn(ch))
 834                         strbuf_addch(sb, ch);
 835                 else
 836                         strbuf_addf(sb, "%%%02x", (unsigned char)ch);
 837         }
 838 }
 839
 840 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 841                              char_predicate allow_unencoded_fn)
 842 {
 843         strbuf_add_urlencode(sb, s, strlen(s), allow_unencoded_fn);
 844 }
 845
 846 static void strbuf_humanise(struct strbuf *buf, off_t bytes,
 847                                  int humanise_rate)
 848 {
 849         if (bytes > 1 << 30) {
 850                 strbuf_addf(buf,
 851                                 humanise_rate == 0 ?
 852                                         /* TRANSLATORS: IEC 80000-13:2008 gibibyte */
 853                                         _("%u.%2.2u GiB") :
 854                                         /* TRANSLATORS: IEC 80000-13:2008 gibibyte/second */
 855                                         _("%u.%2.2u GiB/s"),
 856                             (unsigned)(bytes >> 30),
 857                             (unsigned)(bytes & ((1 << 30) - 1)) / 10737419);
 858         } else if (bytes > 1 << 20) {
 859                 unsigned x = bytes + 5243;  /* for rounding */
 860                 strbuf_addf(buf,
 861                                 humanise_rate == 0 ?
 862                                         /* TRANSLATORS: IEC 80000-13:2008 mebibyte */
 863                                         _("%u.%2.2u MiB") :
 864                                         /* TRANSLATORS: IEC 80000-13:2008 mebibyte/second */
 865                                         _("%u.%2.2u MiB/s"),
 866                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 867         } else if (bytes > 1 << 10) {
 868                 unsigned x = bytes + 5;  /* for rounding */
 869                 strbuf_addf(buf,
 870                                 humanise_rate == 0 ?
 871                                         /* TRANSLATORS: IEC 80000-13:2008 kibibyte */
 872                                         _("%u.%2.2u KiB") :
 873                                         /* TRANSLATORS: IEC 80000-13:2008 kibibyte/second */
 874                                         _("%u.%2.2u KiB/s"),
 875                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 876         } else {
 877                 strbuf_addf(buf,
 878                                 humanise_rate == 0 ?
 879                                         /* TRANSLATORS: IEC 80000-13:2008 byte */
 880                                         Q_("%u byte", "%u bytes", bytes) :
 881                                         /* TRANSLATORS: IEC 80000-13:2008 byte/second */
 882                                         Q_("%u byte/s", "%u bytes/s", bytes),
 883                                 (unsigned)bytes);
 884         }
 885 }
 886
 887 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 888 {
 889         strbuf_humanise(buf, bytes, 0);
 890 }
 891
 892 void strbuf_humanise_rate(struct strbuf *buf, off_t bytes)
 893 {
 894         strbuf_humanise(buf, bytes, 1);
 895 }
 896
 897 void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 898 {
 899         if (!*path)
 900                 die("The empty string is not a valid path");
 901         if (!is_absolute_path(path)) {
 902                 struct stat cwd_stat, pwd_stat;
 903                 size_t orig_len = sb->len;
 904                 char *cwd = xgetcwd();
 905                 char *pwd = getenv("PWD");
 906                 if (pwd && strcmp(pwd, cwd) &&
 907                     !stat(cwd, &cwd_stat) &&
 908                     (cwd_stat.st_dev || cwd_stat.st_ino) &&
 909                     !stat(pwd, &pwd_stat) &&
 910                     pwd_stat.st_dev == cwd_stat.st_dev &&
 911                     pwd_stat.st_ino == cwd_stat.st_ino)
 912                         strbuf_addstr(sb, pwd);
 913                 else
 914                         strbuf_addstr(sb, cwd);
 915                 if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 916                         strbuf_addch(sb, '/');
 917                 free(cwd);
 918         }
 919         strbuf_addstr(sb, path);
 920 }
 921
 922 void strbuf_add_real_path(struct strbuf *sb, const char *path)
 923 {
 924         if (sb->len) {
 925                 struct strbuf resolved = STRBUF_INIT;
 926                 strbuf_realpath(&resolved, path, 1);
 927                 strbuf_addbuf(sb, &resolved);
 928                 strbuf_release(&resolved);
 929         } else
 930                 strbuf_realpath(sb, path, 1);
 931 }
 932
 933 int printf_ln(const char *fmt, ...)
 934 {
 935         int ret;
 936         va_list ap;
 937         va_start(ap, fmt);
 938         ret = vprintf(fmt, ap);
 939         va_end(ap);
 940         if (ret < 0 || putchar('\n') == EOF)
 941                 return -1;
 942         return ret + 1;
 943 }
 944
 945 int fprintf_ln(FILE *fp, const char *fmt, ...)
 946 {
 947         int ret;
 948         va_list ap;
 949         va_start(ap, fmt);
 950         ret = vfprintf(fp, fmt, ap);
 951         va_end(ap);
 952         if (ret < 0 || putc('\n', fp) == EOF)
 953                 return -1;
 954         return ret + 1;
 955 }
 956
 957 char *xstrdup_tolower(const char *string)
 958 {
 959         char *result;
 960         size_t len, i;
 961
 962         len = strlen(string);
 963         result = xmallocz(len);
 964         for (i = 0; i < len; i++)
 965                 result[i] = tolower(string[i]);
 966         return result;
 967 }
 968
 969 char *xstrdup_toupper(const char *string)
 970 {
 971         char *result;
 972         size_t len, i;
 973
 974         len = strlen(string);
 975         result = xmallocz(len);
 976         for (i = 0; i < len; i++)
 977                 result[i] = toupper(string[i]);
 978         return result;
 979 }
 980
 981 char *xstrvfmt(const char *fmt, va_list ap)
 982 {
 983         struct strbuf buf = STRBUF_INIT;
 984         strbuf_vaddf(&buf, fmt, ap);
 985         return strbuf_detach(&buf, NULL);
 986 }
 987
 988 char *xstrfmt(const char *fmt, ...)
 989 {
 990         va_list ap;
 991         char *ret;
 992
 993         va_start(ap, fmt);
 994         ret = xstrvfmt(fmt, ap);
 995         va_end(ap);
 996
 997         return ret;
 998 }
 999
1000 void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
1001                      int tz_offset, int suppress_tz_name)
1002 {
1003         struct strbuf munged_fmt = STRBUF_INIT;
1004         size_t hint = 128;
1005         size_t len;
1006
1007         if (!*fmt)
1008                 return;
1009
1010         /*
1011          * There is no portable way to pass timezone information to
1012          * strftime, so we handle %z and %Z here. Likewise '%s', because
1013          * going back to an epoch time requires knowing the zone.
1014          *
1015          * Note that tz_offset is in the "[-+]HHMM" decimal form; this is what
1016          * we want for %z, but the computation for %s has to convert to number
1017          * of seconds.
1018          */
1019         for (;;) {
1020                 const char *percent = strchrnul(fmt, '%');
1021                 strbuf_add(&munged_fmt, fmt, percent - fmt);
1022                 if (!*percent)
1023                         break;
1024                 fmt = percent + 1;
1025                 switch (*fmt) {
1026                 case '%':
1027                         strbuf_addstr(&munged_fmt, "%%");
1028                         fmt++;
1029                         break;
1030                 case 's':
1031                         strbuf_addf(&munged_fmt, "%"PRItime,
1032                                     (timestamp_t)tm_to_time_t(tm) -
1033                                     3600 * (tz_offset / 100) -
1034                                     60 * (tz_offset % 100));
1035                         fmt++;
1036                         break;
1037                 case 'z':
1038                         strbuf_addf(&munged_fmt, "%+05d", tz_offset);
1039                         fmt++;
1040                         break;
1041                 case 'Z':
1042                         if (suppress_tz_name) {
1043                                 fmt++;
1044                                 break;
1045                         }
1046                         /* FALLTHROUGH */
1047                 default:
1048                         strbuf_addch(&munged_fmt, '%');
1049                 }
1050         }
1051         fmt = munged_fmt.buf;
1052
1053         strbuf_grow(sb, hint);
1054         len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
1055
1056         if (!len) {
1057                 /*
1058                  * strftime reports "0" if it could not fit the result in the buffer.
1059                  * Unfortunately, it also reports "0" if the requested time string
1060                  * takes 0 bytes. So our strategy is to munge the format so that the
1061                  * output contains at least one character, and then drop the extra
1062                  * character before returning.
1063                  */
1064                 strbuf_addch(&munged_fmt, ' ');
1065                 while (!len) {
1066                         hint *= 2;
1067                         strbuf_grow(sb, hint);
1068                         len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
1069                                        munged_fmt.buf, tm);
1070                 }
1071                 len--; /* drop munged space */
1072         }
1073         strbuf_release(&munged_fmt);
1074         strbuf_setlen(sb, sb->len + len);
1075 }
1076
1077 void strbuf_repo_add_unique_abbrev(struct strbuf *sb, struct repository *repo,
1078                                    const struct object_id *oid, int abbrev_len)
1079 {
1080         int r;
1081         strbuf_grow(sb, GIT_MAX_HEXSZ + 1);
1082         r = repo_find_unique_abbrev_r(repo, sb->buf + sb->len, oid, abbrev_len);
1083         strbuf_setlen(sb, sb->len + r);
1084 }
1085
1086 void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
1087                               int abbrev_len)
1088 {
1089         strbuf_repo_add_unique_abbrev(sb, the_repository, oid, abbrev_len);
1090 }
1091
1092 /*
1093  * Returns the length of a line, without trailing spaces.
1094  *
1095  * If the line ends with newline, it will be removed too.
1096  */
1097 static size_t cleanup(char *line, size_t len)
1098 {
1099         while (len) {
1100                 unsigned char c = line[len - 1];
1101                 if (!isspace(c))
1102                         break;
1103                 len--;
1104         }
1105
1106         return len;
1107 }
1108
1109 /*
1110  * Remove empty lines from the beginning and end
1111  * and also trailing spaces from every line.
1112  *
1113  * Turn multiple consecutive empty lines between paragraphs
1114  * into just one empty line.
1115  *
1116  * If the input has only empty lines and spaces,
1117  * no output will be produced.
1118  *
1119  * If last line does not have a newline at the end, one is added.
1120  *
1121  * Enable skip_comments to skip every line starting with comment
1122  * character.
1123  */
1124 void strbuf_stripspace(struct strbuf *sb, int skip_comments)
1125 {
1126         size_t empties = 0;
1127         size_t i, j, len, newlen;
1128         char *eol;
1129
1130         /* We may have to add a newline. */
1131         strbuf_grow(sb, 1);
1132
1133         for (i = j = 0; i < sb->len; i += len, j += newlen) {
1134                 eol = memchr(sb->buf + i, '\n', sb->len - i);
1135                 len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
1136
1137                 if (skip_comments && len && sb->buf[i] == comment_line_char) {
1138                         newlen = 0;
1139                         continue;
1140                 }
1141                 newlen = cleanup(sb->buf + i, len);
1142
1143                 /* Not just an empty line? */
1144                 if (newlen) {
1145                         if (empties > 0 && j > 0)
1146                                 sb->buf[j++] = '\n';
1147                         empties = 0;
1148                         memmove(sb->buf + j, sb->buf + i, newlen);
1149                         sb->buf[newlen + j++] = '\n';
1150                 } else {
1151                         empties++;
1152                 }
1153         }
1154
1155         strbuf_setlen(sb, j);
1156 }
1157
1158 int strbuf_normalize_path(struct strbuf *src)
1159 {
1160         struct strbuf dst = STRBUF_INIT;
1161
1162         strbuf_grow(&dst, src->len);
1163         if (normalize_path_copy(dst.buf, src->buf) < 0) {
1164                 strbuf_release(&dst);
1165                 return -1;
1166         }
1167
1168         /*
1169          * normalize_path does not tell us the new length, so we have to
1170          * compute it by looking for the new NUL it placed
1171          */
1172         strbuf_setlen(&dst, strlen(dst.buf));
1173         strbuf_swap(src, &dst);
1174         strbuf_release(&dst);
1175         return 0;
1176 }
1177
1178 int strbuf_edit_interactively(struct strbuf *buffer, const char *path,
1179                               const char *const *env)
1180 {
1181         char *path2 = NULL;
1182         int fd, res = 0;
1183
1184         if (!is_absolute_path(path))
1185                 path = path2 = xstrdup(git_path("%s", path));
1186
1187         fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0666);
1188         if (fd < 0)
1189                 res = error_errno(_("could not open '%s' for writing"), path);
1190         else if (write_in_full(fd, buffer->buf, buffer->len) < 0) {
1191                 res = error_errno(_("could not write to '%s'"), path);
1192                 close(fd);
1193         } else if (close(fd) < 0)
1194                 res = error_errno(_("could not close '%s'"), path);
1195         else {
1196                 strbuf_reset(buffer);
1197                 if (launch_editor(path, buffer, env) < 0)
1198                         res = error_errno(_("could not edit '%s'"), path);
1199                 unlink(path);
1200         }
1201
1202         free(path2);
1203         return res;
1204 }
1205
1206 void strbuf_strip_file_from_path(struct strbuf *sb)
1207 {
1208         char *path_sep = find_last_dir_sep(sb->buf);
1209         strbuf_setlen(sb, path_sep ? path_sep - sb->buf + 1 : 0);
1210 }