Andrew's git / gitweb.git / strbuf.c
?
strbuf.con commit Merge branch 'cc/perf-bisect' (0264531)
   1#include "cache.h"
   2#include "refs.h"
   3#include "utf8.h"
   4
   5int starts_with(const char *str, const char *prefix)
   6{
   7        for (; ; str++, prefix++)
   8                if (!*prefix)
   9                        return 1;
  10                else if (*str != *prefix)
  11                        return 0;
  12}
  13
  14int skip_to_optional_arg_default(const char *str, const char *prefix,
  15                                 const char **arg, const char *def)
  16{
  17        const char *p;
  18
  19        if (!skip_prefix(str, prefix, &p))
  20                return 0;
  21
  22        if (!*p) {
  23                if (arg)
  24                        *arg = def;
  25                return 1;
  26        }
  27
  28        if (*p != '=')
  29                return 0;
  30
  31        if (arg)
  32                *arg = p + 1;
  33        return 1;
  34}
  35
  36/*
  37 * Used as the default ->buf value, so that people can always assume
  38 * buf is non NULL and ->buf is NUL terminated even for a freshly
  39 * initialized strbuf.
  40 */
  41char strbuf_slopbuf[1];
  42
  43void strbuf_init(struct strbuf *sb, size_t hint)
  44{
  45        sb->alloc = sb->len = 0;
  46        sb->buf = strbuf_slopbuf;
  47        if (hint)
  48                strbuf_grow(sb, hint);
  49}
  50
  51void strbuf_release(struct strbuf *sb)
  52{
  53        if (sb->alloc) {
  54                free(sb->buf);
  55                strbuf_init(sb, 0);
  56        }
  57}
  58
  59char *strbuf_detach(struct strbuf *sb, size_t *sz)
  60{
  61        char *res;
  62        strbuf_grow(sb, 0);
  63        res = sb->buf;
  64        if (sz)
  65                *sz = sb->len;
  66        strbuf_init(sb, 0);
  67        return res;
  68}
  69
  70void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  71{
  72        strbuf_release(sb);
  73        sb->buf   = buf;
  74        sb->len   = len;
  75        sb->alloc = alloc;
  76        strbuf_grow(sb, 0);
  77        sb->buf[sb->len] = '\0';
  78}
  79
  80void strbuf_grow(struct strbuf *sb, size_t extra)
  81{
  82        int new_buf = !sb->alloc;
  83        if (unsigned_add_overflows(extra, 1) ||
  84            unsigned_add_overflows(sb->len, extra + 1))
  85                die("you want to use way too much memory");
  86        if (new_buf)
  87                sb->buf = NULL;
  88        ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  89        if (new_buf)
  90                sb->buf[0] = '\0';
  91}
  92
  93void strbuf_trim(struct strbuf *sb)
  94{
  95        strbuf_rtrim(sb);
  96        strbuf_ltrim(sb);
  97}
  98
  99void strbuf_rtrim(struct strbuf *sb)
 100{
 101        while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
 102                sb->len--;
 103        sb->buf[sb->len] = '\0';
 104}
 105
 106void strbuf_trim_trailing_dir_sep(struct strbuf *sb)
 107{
 108        while (sb->len > 0 && is_dir_sep((unsigned char)sb->buf[sb->len - 1]))
 109                sb->len--;
 110        sb->buf[sb->len] = '\0';
 111}
 112
 113void strbuf_ltrim(struct strbuf *sb)
 114{
 115        char *b = sb->buf;
 116        while (sb->len > 0 && isspace(*b)) {
 117                b++;
 118                sb->len--;
 119        }
 120        memmove(sb->buf, b, sb->len);
 121        sb->buf[sb->len] = '\0';
 122}
 123
 124int strbuf_reencode(struct strbuf *sb, const char *from, const char *to)
 125{
 126        char *out;
 127        int len;
 128
 129        if (same_encoding(from, to))
 130                return 0;
 131
 132        out = reencode_string_len(sb->buf, sb->len, to, from, &len);
 133        if (!out)
 134                return -1;
 135
 136        strbuf_attach(sb, out, len, len);
 137        return 0;
 138}
 139
 140void strbuf_tolower(struct strbuf *sb)
 141{
 142        char *p = sb->buf, *end = sb->buf + sb->len;
 143        for (; p < end; p++)
 144                *p = tolower(*p);
 145}
 146
 147struct strbuf **strbuf_split_buf(const char *str, size_t slen,
 148                                 int terminator, int max)
 149{
 150        struct strbuf **ret = NULL;
 151        size_t nr = 0, alloc = 0;
 152        struct strbuf *t;
 153
 154        while (slen) {
 155                int len = slen;
 156                if (max <= 0 || nr + 1 < max) {
 157                        const char *end = memchr(str, terminator, slen);
 158                        if (end)
 159                                len = end - str + 1;
 160                }
 161                t = xmalloc(sizeof(struct strbuf));
 162                strbuf_init(t, len);
 163                strbuf_add(t, str, len);
 164                ALLOC_GROW(ret, nr + 2, alloc);
 165                ret[nr++] = t;
 166                str += len;
 167                slen -= len;
 168        }
 169        ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 170        ret[nr] = NULL;
 171        return ret;
 172}
 173
 174void strbuf_list_free(struct strbuf **sbs)
 175{
 176        struct strbuf **s = sbs;
 177
 178        while (*s) {
 179                strbuf_release(*s);
 180                free(*s++);
 181        }
 182        free(sbs);
 183}
 184
 185int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 186{
 187        int len = a->len < b->len ? a->len: b->len;
 188        int cmp = memcmp(a->buf, b->buf, len);
 189        if (cmp)
 190                return cmp;
 191        return a->len < b->len ? -1: a->len != b->len;
 192}
 193
 194void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 195                                   const void *data, size_t dlen)
 196{
 197        if (unsigned_add_overflows(pos, len))
 198                die("you want to use way too much memory");
 199        if (pos > sb->len)
 200                die("`pos' is too far after the end of the buffer");
 201        if (pos + len > sb->len)
 202                die("`pos + len' is too far after the end of the buffer");
 203
 204        if (dlen >= len)
 205                strbuf_grow(sb, dlen - len);
 206        memmove(sb->buf + pos + dlen,
 207                        sb->buf + pos + len,
 208                        sb->len - pos - len);
 209        memcpy(sb->buf + pos, data, dlen);
 210        strbuf_setlen(sb, sb->len + dlen - len);
 211}
 212
 213void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 214{
 215        strbuf_splice(sb, pos, 0, data, len);
 216}
 217
 218void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 219{
 220        strbuf_splice(sb, pos, len, "", 0);
 221}
 222
 223void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 224{
 225        strbuf_grow(sb, len);
 226        memcpy(sb->buf + sb->len, data, len);
 227        strbuf_setlen(sb, sb->len + len);
 228}
 229
 230void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
 231{
 232        strbuf_grow(sb, sb2->len);
 233        memcpy(sb->buf + sb->len, sb2->buf, sb2->len);
 234        strbuf_setlen(sb, sb->len + sb2->len);
 235}
 236
 237void strbuf_addchars(struct strbuf *sb, int c, size_t n)
 238{
 239        strbuf_grow(sb, n);
 240        memset(sb->buf + sb->len, c, n);
 241        strbuf_setlen(sb, sb->len + n);
 242}
 243
 244void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 245{
 246        va_list ap;
 247        va_start(ap, fmt);
 248        strbuf_vaddf(sb, fmt, ap);
 249        va_end(ap);
 250}
 251
 252static void add_lines(struct strbuf *out,
 253                        const char *prefix1,
 254                        const char *prefix2,
 255                        const char *buf, size_t size)
 256{
 257        while (size) {
 258                const char *prefix;
 259                const char *next = memchr(buf, '\n', size);
 260                next = next ? (next + 1) : (buf + size);
 261
 262                prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
 263                          ? prefix2 : prefix1);
 264                strbuf_addstr(out, prefix);
 265                strbuf_add(out, buf, next - buf);
 266                size -= next - buf;
 267                buf = next;
 268        }
 269        strbuf_complete_line(out);
 270}
 271
 272void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 273{
 274        static char prefix1[3];
 275        static char prefix2[2];
 276
 277        if (prefix1[0] != comment_line_char) {
 278                xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
 279                xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
 280        }
 281        add_lines(out, prefix1, prefix2, buf, size);
 282}
 283
 284void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 285{
 286        va_list params;
 287        struct strbuf buf = STRBUF_INIT;
 288        int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 289
 290        va_start(params, fmt);
 291        strbuf_vaddf(&buf, fmt, params);
 292        va_end(params);
 293
 294        strbuf_add_commented_lines(sb, buf.buf, buf.len);
 295        if (incomplete_line)
 296                sb->buf[--sb->len] = '\0';
 297
 298        strbuf_release(&buf);
 299}
 300
 301void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 302{
 303        int len;
 304        va_list cp;
 305
 306        if (!strbuf_avail(sb))
 307                strbuf_grow(sb, 64);
 308        va_copy(cp, ap);
 309        len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 310        va_end(cp);
 311        if (len < 0)
 312                die("BUG: your vsnprintf is broken (returned %d)", len);
 313        if (len > strbuf_avail(sb)) {
 314                strbuf_grow(sb, len);
 315                len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 316                if (len > strbuf_avail(sb))
 317                        die("BUG: your vsnprintf is broken (insatiable)");
 318        }
 319        strbuf_setlen(sb, sb->len + len);
 320}
 321
 322void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 323                   void *context)
 324{
 325        for (;;) {
 326                const char *percent;
 327                size_t consumed;
 328
 329                percent = strchrnul(format, '%');
 330                strbuf_add(sb, format, percent - format);
 331                if (!*percent)
 332                        break;
 333                format = percent + 1;
 334
 335                if (*format == '%') {
 336                        strbuf_addch(sb, '%');
 337                        format++;
 338                        continue;
 339                }
 340
 341                consumed = fn(sb, format, context);
 342                if (consumed)
 343                        format += consumed;
 344                else
 345                        strbuf_addch(sb, '%');
 346        }
 347}
 348
 349size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 350                void *context)
 351{
 352        struct strbuf_expand_dict_entry *e = context;
 353        size_t len;
 354
 355        for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 356                if (!strncmp(placeholder, e->placeholder, len)) {
 357                        if (e->value)
 358                                strbuf_addstr(sb, e->value);
 359                        return len;
 360                }
 361        }
 362        return 0;
 363}
 364
 365void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 366{
 367        int i, len = src->len;
 368
 369        for (i = 0; i < len; i++) {
 370                if (src->buf[i] == '%')
 371                        strbuf_addch(dst, '%');
 372                strbuf_addch(dst, src->buf[i]);
 373        }
 374}
 375
 376size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 377{
 378        size_t res;
 379        size_t oldalloc = sb->alloc;
 380
 381        strbuf_grow(sb, size);
 382        res = fread(sb->buf + sb->len, 1, size, f);
 383        if (res > 0)
 384                strbuf_setlen(sb, sb->len + res);
 385        else if (oldalloc == 0)
 386                strbuf_release(sb);
 387        return res;
 388}
 389
 390ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 391{
 392        size_t oldlen = sb->len;
 393        size_t oldalloc = sb->alloc;
 394
 395        strbuf_grow(sb, hint ? hint : 8192);
 396        for (;;) {
 397                ssize_t want = sb->alloc - sb->len - 1;
 398                ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
 399
 400                if (got < 0) {
 401                        if (oldalloc == 0)
 402                                strbuf_release(sb);
 403                        else
 404                                strbuf_setlen(sb, oldlen);
 405                        return -1;
 406                }
 407                sb->len += got;
 408                if (got < want)
 409                        break;
 410                strbuf_grow(sb, 8192);
 411        }
 412
 413        sb->buf[sb->len] = '\0';
 414        return sb->len - oldlen;
 415}
 416
 417ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
 418{
 419        size_t oldalloc = sb->alloc;
 420        ssize_t cnt;
 421
 422        strbuf_grow(sb, hint ? hint : 8192);
 423        cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 424        if (cnt > 0)
 425                strbuf_setlen(sb, sb->len + cnt);
 426        else if (oldalloc == 0)
 427                strbuf_release(sb);
 428        return cnt;
 429}
 430
 431ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 432{
 433        return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 434}
 435
 436
 437#define STRBUF_MAXLINK (2*PATH_MAX)
 438
 439int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 440{
 441        size_t oldalloc = sb->alloc;
 442
 443        if (hint < 32)
 444                hint = 32;
 445
 446        while (hint < STRBUF_MAXLINK) {
 447                int len;
 448
 449                strbuf_grow(sb, hint);
 450                len = readlink(path, sb->buf, hint);
 451                if (len < 0) {
 452                        if (errno != ERANGE)
 453                                break;
 454                } else if (len < hint) {
 455                        strbuf_setlen(sb, len);
 456                        return 0;
 457                }
 458
 459                /* .. the buffer was too small - try again */
 460                hint *= 2;
 461        }
 462        if (oldalloc == 0)
 463                strbuf_release(sb);
 464        return -1;
 465}
 466
 467int strbuf_getcwd(struct strbuf *sb)
 468{
 469        size_t oldalloc = sb->alloc;
 470        size_t guessed_len = 128;
 471
 472        for (;; guessed_len *= 2) {
 473                strbuf_grow(sb, guessed_len);
 474                if (getcwd(sb->buf, sb->alloc)) {
 475                        strbuf_setlen(sb, strlen(sb->buf));
 476                        return 0;
 477                }
 478
 479                /*
 480                 * If getcwd(3) is implemented as a syscall that falls
 481                 * back to a regular lookup using readdir(3) etc. then
 482                 * we may be able to avoid EACCES by providing enough
 483                 * space to the syscall as it's not necessarily bound
 484                 * to the same restrictions as the fallback.
 485                 */
 486                if (errno == EACCES && guessed_len < PATH_MAX)
 487                        continue;
 488
 489                if (errno != ERANGE)
 490                        break;
 491        }
 492        if (oldalloc == 0)
 493                strbuf_release(sb);
 494        else
 495                strbuf_reset(sb);
 496        return -1;
 497}
 498
 499#ifdef HAVE_GETDELIM
 500int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 501{
 502        ssize_t r;
 503
 504        if (feof(fp))
 505                return EOF;
 506
 507        strbuf_reset(sb);
 508
 509        /* Translate slopbuf to NULL, as we cannot call realloc on it */
 510        if (!sb->alloc)
 511                sb->buf = NULL;
 512        errno = 0;
 513        r = getdelim(&sb->buf, &sb->alloc, term, fp);
 514
 515        if (r > 0) {
 516                sb->len = r;
 517                return 0;
 518        }
 519        assert(r == -1);
 520
 521        /*
 522         * Normally we would have called xrealloc, which will try to free
 523         * memory and recover. But we have no way to tell getdelim() to do so.
 524         * Worse, we cannot try to recover ENOMEM ourselves, because we have
 525         * no idea how many bytes were read by getdelim.
 526         *
 527         * Dying here is reasonable. It mirrors what xrealloc would do on
 528         * catastrophic memory failure. We skip the opportunity to free pack
 529         * memory and retry, but that's unlikely to help for a malloc small
 530         * enough to hold a single line of input, anyway.
 531         */
 532        if (errno == ENOMEM)
 533                die("Out of memory, getdelim failed");
 534
 535        /*
 536         * Restore strbuf invariants; if getdelim left us with a NULL pointer,
 537         * we can just re-init, but otherwise we should make sure that our
 538         * length is empty, and that the result is NUL-terminated.
 539         */
 540        if (!sb->buf)
 541                strbuf_init(sb, 0);
 542        else
 543                strbuf_reset(sb);
 544        return EOF;
 545}
 546#else
 547int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 548{
 549        int ch;
 550
 551        if (feof(fp))
 552                return EOF;
 553
 554        strbuf_reset(sb);
 555        flockfile(fp);
 556        while ((ch = getc_unlocked(fp)) != EOF) {
 557                if (!strbuf_avail(sb))
 558                        strbuf_grow(sb, 1);
 559                sb->buf[sb->len++] = ch;
 560                if (ch == term)
 561                        break;
 562        }
 563        funlockfile(fp);
 564        if (ch == EOF && sb->len == 0)
 565                return EOF;
 566
 567        sb->buf[sb->len] = '\0';
 568        return 0;
 569}
 570#endif
 571
 572static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 573{
 574        if (strbuf_getwholeline(sb, fp, term))
 575                return EOF;
 576        if (sb->buf[sb->len - 1] == term)
 577                strbuf_setlen(sb, sb->len - 1);
 578        return 0;
 579}
 580
 581int strbuf_getline(struct strbuf *sb, FILE *fp)
 582{
 583        if (strbuf_getwholeline(sb, fp, '\n'))
 584                return EOF;
 585        if (sb->buf[sb->len - 1] == '\n') {
 586                strbuf_setlen(sb, sb->len - 1);
 587                if (sb->len && sb->buf[sb->len - 1] == '\r')
 588                        strbuf_setlen(sb, sb->len - 1);
 589        }
 590        return 0;
 591}
 592
 593int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 594{
 595        return strbuf_getdelim(sb, fp, '\n');
 596}
 597
 598int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 599{
 600        return strbuf_getdelim(sb, fp, '\0');
 601}
 602
 603int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 604{
 605        strbuf_reset(sb);
 606
 607        while (1) {
 608                char ch;
 609                ssize_t len = xread(fd, &ch, 1);
 610                if (len <= 0)
 611                        return EOF;
 612                strbuf_addch(sb, ch);
 613                if (ch == term)
 614                        break;
 615        }
 616        return 0;
 617}
 618
 619ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 620{
 621        int fd;
 622        ssize_t len;
 623        int saved_errno;
 624
 625        fd = open(path, O_RDONLY);
 626        if (fd < 0)
 627                return -1;
 628        len = strbuf_read(sb, fd, hint);
 629        saved_errno = errno;
 630        close(fd);
 631        if (len < 0) {
 632                errno = saved_errno;
 633                return -1;
 634        }
 635
 636        return len;
 637}
 638
 639void strbuf_add_lines(struct strbuf *out, const char *prefix,
 640                      const char *buf, size_t size)
 641{
 642        add_lines(out, prefix, NULL, buf, size);
 643}
 644
 645void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 646{
 647        while (*s) {
 648                size_t len = strcspn(s, "\"<>&");
 649                strbuf_add(buf, s, len);
 650                s += len;
 651                switch (*s) {
 652                case '"':
 653                        strbuf_addstr(buf, "&quot;");
 654                        break;
 655                case '<':
 656                        strbuf_addstr(buf, "&lt;");
 657                        break;
 658                case '>':
 659                        strbuf_addstr(buf, "&gt;");
 660                        break;
 661                case '&':
 662                        strbuf_addstr(buf, "&amp;");
 663                        break;
 664                case 0:
 665                        return;
 666                }
 667                s++;
 668        }
 669}
 670
 671static int is_rfc3986_reserved(char ch)
 672{
 673        switch (ch) {
 674                case '!': case '*': case '\'': case '(': case ')': case ';':
 675                case ':': case '@': case '&': case '=': case '+': case '$':
 676                case ',': case '/': case '?': case '#': case '[': case ']':
 677                        return 1;
 678        }
 679        return 0;
 680}
 681
 682static int is_rfc3986_unreserved(char ch)
 683{
 684        return isalnum(ch) ||
 685                ch == '-' || ch == '_' || ch == '.' || ch == '~';
 686}
 687
 688static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 689                                 int reserved)
 690{
 691        strbuf_grow(sb, len);
 692        while (len--) {
 693                char ch = *s++;
 694                if (is_rfc3986_unreserved(ch) ||
 695                    (!reserved && is_rfc3986_reserved(ch)))
 696                        strbuf_addch(sb, ch);
 697                else
 698                        strbuf_addf(sb, "%%%02x", (unsigned char)ch);
 699        }
 700}
 701
 702void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 703                             int reserved)
 704{
 705        strbuf_add_urlencode(sb, s, strlen(s), reserved);
 706}
 707
 708void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 709{
 710        if (bytes > 1 << 30) {
 711                strbuf_addf(buf, "%u.%2.2u GiB",
 712                            (int)(bytes >> 30),
 713                            (int)(bytes & ((1 << 30) - 1)) / 10737419);
 714        } else if (bytes > 1 << 20) {
 715                int x = bytes + 5243;  /* for rounding */
 716                strbuf_addf(buf, "%u.%2.2u MiB",
 717                            x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 718        } else if (bytes > 1 << 10) {
 719                int x = bytes + 5;  /* for rounding */
 720                strbuf_addf(buf, "%u.%2.2u KiB",
 721                            x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 722        } else {
 723                strbuf_addf(buf, "%u bytes", (int)bytes);
 724        }
 725}
 726
 727void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 728{
 729        if (!*path)
 730                die("The empty string is not a valid path");
 731        if (!is_absolute_path(path)) {
 732                struct stat cwd_stat, pwd_stat;
 733                size_t orig_len = sb->len;
 734                char *cwd = xgetcwd();
 735                char *pwd = getenv("PWD");
 736                if (pwd && strcmp(pwd, cwd) &&
 737                    !stat(cwd, &cwd_stat) &&
 738                    (cwd_stat.st_dev || cwd_stat.st_ino) &&
 739                    !stat(pwd, &pwd_stat) &&
 740                    pwd_stat.st_dev == cwd_stat.st_dev &&
 741                    pwd_stat.st_ino == cwd_stat.st_ino)
 742                        strbuf_addstr(sb, pwd);
 743                else
 744                        strbuf_addstr(sb, cwd);
 745                if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 746                        strbuf_addch(sb, '/');
 747                free(cwd);
 748        }
 749        strbuf_addstr(sb, path);
 750}
 751
 752void strbuf_add_real_path(struct strbuf *sb, const char *path)
 753{
 754        if (sb->len) {
 755                struct strbuf resolved = STRBUF_INIT;
 756                strbuf_realpath(&resolved, path, 1);
 757                strbuf_addbuf(sb, &resolved);
 758                strbuf_release(&resolved);
 759        } else
 760                strbuf_realpath(sb, path, 1);
 761}
 762
 763int printf_ln(const char *fmt, ...)
 764{
 765        int ret;
 766        va_list ap;
 767        va_start(ap, fmt);
 768        ret = vprintf(fmt, ap);
 769        va_end(ap);
 770        if (ret < 0 || putchar('\n') == EOF)
 771                return -1;
 772        return ret + 1;
 773}
 774
 775int fprintf_ln(FILE *fp, const char *fmt, ...)
 776{
 777        int ret;
 778        va_list ap;
 779        va_start(ap, fmt);
 780        ret = vfprintf(fp, fmt, ap);
 781        va_end(ap);
 782        if (ret < 0 || putc('\n', fp) == EOF)
 783                return -1;
 784        return ret + 1;
 785}
 786
 787char *xstrdup_tolower(const char *string)
 788{
 789        char *result;
 790        size_t len, i;
 791
 792        len = strlen(string);
 793        result = xmallocz(len);
 794        for (i = 0; i < len; i++)
 795                result[i] = tolower(string[i]);
 796        result[i] = '\0';
 797        return result;
 798}
 799
 800char *xstrvfmt(const char *fmt, va_list ap)
 801{
 802        struct strbuf buf = STRBUF_INIT;
 803        strbuf_vaddf(&buf, fmt, ap);
 804        return strbuf_detach(&buf, NULL);
 805}
 806
 807char *xstrfmt(const char *fmt, ...)
 808{
 809        va_list ap;
 810        char *ret;
 811
 812        va_start(ap, fmt);
 813        ret = xstrvfmt(fmt, ap);
 814        va_end(ap);
 815
 816        return ret;
 817}
 818
 819void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 820                     int tz_offset, int suppress_tz_name)
 821{
 822        struct strbuf munged_fmt = STRBUF_INIT;
 823        size_t hint = 128;
 824        size_t len;
 825
 826        if (!*fmt)
 827                return;
 828
 829        /*
 830         * There is no portable way to pass timezone information to
 831         * strftime, so we handle %z and %Z here.
 832         */
 833        for (;;) {
 834                const char *percent = strchrnul(fmt, '%');
 835                strbuf_add(&munged_fmt, fmt, percent - fmt);
 836                if (!*percent)
 837                        break;
 838                fmt = percent + 1;
 839                switch (*fmt) {
 840                case '%':
 841                        strbuf_addstr(&munged_fmt, "%%");
 842                        fmt++;
 843                        break;
 844                case 'z':
 845                        strbuf_addf(&munged_fmt, "%+05d", tz_offset);
 846                        fmt++;
 847                        break;
 848                case 'Z':
 849                        if (suppress_tz_name) {
 850                                fmt++;
 851                                break;
 852                        }
 853                        /* FALLTHROUGH */
 854                default:
 855                        strbuf_addch(&munged_fmt, '%');
 856                }
 857        }
 858        fmt = munged_fmt.buf;
 859
 860        strbuf_grow(sb, hint);
 861        len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
 862
 863        if (!len) {
 864                /*
 865                 * strftime reports "0" if it could not fit the result in the buffer.
 866                 * Unfortunately, it also reports "0" if the requested time string
 867                 * takes 0 bytes. So our strategy is to munge the format so that the
 868                 * output contains at least one character, and then drop the extra
 869                 * character before returning.
 870                 */
 871                strbuf_addch(&munged_fmt, ' ');
 872                while (!len) {
 873                        hint *= 2;
 874                        strbuf_grow(sb, hint);
 875                        len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
 876                                       munged_fmt.buf, tm);
 877                }
 878                len--; /* drop munged space */
 879        }
 880        strbuf_release(&munged_fmt);
 881        strbuf_setlen(sb, sb->len + len);
 882}
 883
 884void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
 885                              int abbrev_len)
 886{
 887        int r;
 888        strbuf_grow(sb, GIT_SHA1_HEXSZ + 1);
 889        r = find_unique_abbrev_r(sb->buf + sb->len, oid, abbrev_len);
 890        strbuf_setlen(sb, sb->len + r);
 891}
 892
 893/*
 894 * Returns the length of a line, without trailing spaces.
 895 *
 896 * If the line ends with newline, it will be removed too.
 897 */
 898static size_t cleanup(char *line, size_t len)
 899{
 900        while (len) {
 901                unsigned char c = line[len - 1];
 902                if (!isspace(c))
 903                        break;
 904                len--;
 905        }
 906
 907        return len;
 908}
 909
 910/*
 911 * Remove empty lines from the beginning and end
 912 * and also trailing spaces from every line.
 913 *
 914 * Turn multiple consecutive empty lines between paragraphs
 915 * into just one empty line.
 916 *
 917 * If the input has only empty lines and spaces,
 918 * no output will be produced.
 919 *
 920 * If last line does not have a newline at the end, one is added.
 921 *
 922 * Enable skip_comments to skip every line starting with comment
 923 * character.
 924 */
 925void strbuf_stripspace(struct strbuf *sb, int skip_comments)
 926{
 927        int empties = 0;
 928        size_t i, j, len, newlen;
 929        char *eol;
 930
 931        /* We may have to add a newline. */
 932        strbuf_grow(sb, 1);
 933
 934        for (i = j = 0; i < sb->len; i += len, j += newlen) {
 935                eol = memchr(sb->buf + i, '\n', sb->len - i);
 936                len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
 937
 938                if (skip_comments && len && sb->buf[i] == comment_line_char) {
 939                        newlen = 0;
 940                        continue;
 941                }
 942                newlen = cleanup(sb->buf + i, len);
 943
 944                /* Not just an empty line? */
 945                if (newlen) {
 946                        if (empties > 0 && j > 0)
 947                                sb->buf[j++] = '\n';
 948                        empties = 0;
 949                        memmove(sb->buf + j, sb->buf + i, newlen);
 950                        sb->buf[newlen + j++] = '\n';
 951                } else {
 952                        empties++;
 953                }
 954        }
 955
 956        strbuf_setlen(sb, j);
 957}
 958
 959int strbuf_normalize_path(struct strbuf *src)
 960{
 961        struct strbuf dst = STRBUF_INIT;
 962
 963        strbuf_grow(&dst, src->len);
 964        if (normalize_path_copy(dst.buf, src->buf) < 0) {
 965                strbuf_release(&dst);
 966                return -1;
 967        }
 968
 969        /*
 970         * normalize_path does not tell us the new length, so we have to
 971         * compute it by looking for the new NUL it placed
 972         */
 973        strbuf_setlen(&dst, strlen(dst.buf));
 974        strbuf_swap(src, &dst);
 975        strbuf_release(&dst);
 976        return 0;
 977}