strbuf.con commit archive: convert sha1_file_to_archive to struct object_id (e5ec981)
   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}
  98void strbuf_rtrim(struct strbuf *sb)
  99{
 100        while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
 101                sb->len--;
 102        sb->buf[sb->len] = '\0';
 103}
 104
 105void strbuf_ltrim(struct strbuf *sb)
 106{
 107        char *b = sb->buf;
 108        while (sb->len > 0 && isspace(*b)) {
 109                b++;
 110                sb->len--;
 111        }
 112        memmove(sb->buf, b, sb->len);
 113        sb->buf[sb->len] = '\0';
 114}
 115
 116int strbuf_reencode(struct strbuf *sb, const char *from, const char *to)
 117{
 118        char *out;
 119        int len;
 120
 121        if (same_encoding(from, to))
 122                return 0;
 123
 124        out = reencode_string_len(sb->buf, sb->len, to, from, &len);
 125        if (!out)
 126                return -1;
 127
 128        strbuf_attach(sb, out, len, len);
 129        return 0;
 130}
 131
 132void strbuf_tolower(struct strbuf *sb)
 133{
 134        char *p = sb->buf, *end = sb->buf + sb->len;
 135        for (; p < end; p++)
 136                *p = tolower(*p);
 137}
 138
 139struct strbuf **strbuf_split_buf(const char *str, size_t slen,
 140                                 int terminator, int max)
 141{
 142        struct strbuf **ret = NULL;
 143        size_t nr = 0, alloc = 0;
 144        struct strbuf *t;
 145
 146        while (slen) {
 147                int len = slen;
 148                if (max <= 0 || nr + 1 < max) {
 149                        const char *end = memchr(str, terminator, slen);
 150                        if (end)
 151                                len = end - str + 1;
 152                }
 153                t = xmalloc(sizeof(struct strbuf));
 154                strbuf_init(t, len);
 155                strbuf_add(t, str, len);
 156                ALLOC_GROW(ret, nr + 2, alloc);
 157                ret[nr++] = t;
 158                str += len;
 159                slen -= len;
 160        }
 161        ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 162        ret[nr] = NULL;
 163        return ret;
 164}
 165
 166void strbuf_list_free(struct strbuf **sbs)
 167{
 168        struct strbuf **s = sbs;
 169
 170        while (*s) {
 171                strbuf_release(*s);
 172                free(*s++);
 173        }
 174        free(sbs);
 175}
 176
 177int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 178{
 179        int len = a->len < b->len ? a->len: b->len;
 180        int cmp = memcmp(a->buf, b->buf, len);
 181        if (cmp)
 182                return cmp;
 183        return a->len < b->len ? -1: a->len != b->len;
 184}
 185
 186void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 187                                   const void *data, size_t dlen)
 188{
 189        if (unsigned_add_overflows(pos, len))
 190                die("you want to use way too much memory");
 191        if (pos > sb->len)
 192                die("`pos' is too far after the end of the buffer");
 193        if (pos + len > sb->len)
 194                die("`pos + len' is too far after the end of the buffer");
 195
 196        if (dlen >= len)
 197                strbuf_grow(sb, dlen - len);
 198        memmove(sb->buf + pos + dlen,
 199                        sb->buf + pos + len,
 200                        sb->len - pos - len);
 201        memcpy(sb->buf + pos, data, dlen);
 202        strbuf_setlen(sb, sb->len + dlen - len);
 203}
 204
 205void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 206{
 207        strbuf_splice(sb, pos, 0, data, len);
 208}
 209
 210void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 211{
 212        strbuf_splice(sb, pos, len, "", 0);
 213}
 214
 215void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 216{
 217        strbuf_grow(sb, len);
 218        memcpy(sb->buf + sb->len, data, len);
 219        strbuf_setlen(sb, sb->len + len);
 220}
 221
 222void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
 223{
 224        strbuf_grow(sb, sb2->len);
 225        memcpy(sb->buf + sb->len, sb2->buf, sb2->len);
 226        strbuf_setlen(sb, sb->len + sb2->len);
 227}
 228
 229void strbuf_addchars(struct strbuf *sb, int c, size_t n)
 230{
 231        strbuf_grow(sb, n);
 232        memset(sb->buf + sb->len, c, n);
 233        strbuf_setlen(sb, sb->len + n);
 234}
 235
 236void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 237{
 238        va_list ap;
 239        va_start(ap, fmt);
 240        strbuf_vaddf(sb, fmt, ap);
 241        va_end(ap);
 242}
 243
 244static void add_lines(struct strbuf *out,
 245                        const char *prefix1,
 246                        const char *prefix2,
 247                        const char *buf, size_t size)
 248{
 249        while (size) {
 250                const char *prefix;
 251                const char *next = memchr(buf, '\n', size);
 252                next = next ? (next + 1) : (buf + size);
 253
 254                prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
 255                          ? prefix2 : prefix1);
 256                strbuf_addstr(out, prefix);
 257                strbuf_add(out, buf, next - buf);
 258                size -= next - buf;
 259                buf = next;
 260        }
 261        strbuf_complete_line(out);
 262}
 263
 264void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 265{
 266        static char prefix1[3];
 267        static char prefix2[2];
 268
 269        if (prefix1[0] != comment_line_char) {
 270                xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
 271                xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
 272        }
 273        add_lines(out, prefix1, prefix2, buf, size);
 274}
 275
 276void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 277{
 278        va_list params;
 279        struct strbuf buf = STRBUF_INIT;
 280        int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 281
 282        va_start(params, fmt);
 283        strbuf_vaddf(&buf, fmt, params);
 284        va_end(params);
 285
 286        strbuf_add_commented_lines(sb, buf.buf, buf.len);
 287        if (incomplete_line)
 288                sb->buf[--sb->len] = '\0';
 289
 290        strbuf_release(&buf);
 291}
 292
 293void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 294{
 295        int len;
 296        va_list cp;
 297
 298        if (!strbuf_avail(sb))
 299                strbuf_grow(sb, 64);
 300        va_copy(cp, ap);
 301        len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 302        va_end(cp);
 303        if (len < 0)
 304                die("BUG: your vsnprintf is broken (returned %d)", len);
 305        if (len > strbuf_avail(sb)) {
 306                strbuf_grow(sb, len);
 307                len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 308                if (len > strbuf_avail(sb))
 309                        die("BUG: your vsnprintf is broken (insatiable)");
 310        }
 311        strbuf_setlen(sb, sb->len + len);
 312}
 313
 314void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 315                   void *context)
 316{
 317        for (;;) {
 318                const char *percent;
 319                size_t consumed;
 320
 321                percent = strchrnul(format, '%');
 322                strbuf_add(sb, format, percent - format);
 323                if (!*percent)
 324                        break;
 325                format = percent + 1;
 326
 327                if (*format == '%') {
 328                        strbuf_addch(sb, '%');
 329                        format++;
 330                        continue;
 331                }
 332
 333                consumed = fn(sb, format, context);
 334                if (consumed)
 335                        format += consumed;
 336                else
 337                        strbuf_addch(sb, '%');
 338        }
 339}
 340
 341size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 342                void *context)
 343{
 344        struct strbuf_expand_dict_entry *e = context;
 345        size_t len;
 346
 347        for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 348                if (!strncmp(placeholder, e->placeholder, len)) {
 349                        if (e->value)
 350                                strbuf_addstr(sb, e->value);
 351                        return len;
 352                }
 353        }
 354        return 0;
 355}
 356
 357void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 358{
 359        int i, len = src->len;
 360
 361        for (i = 0; i < len; i++) {
 362                if (src->buf[i] == '%')
 363                        strbuf_addch(dst, '%');
 364                strbuf_addch(dst, src->buf[i]);
 365        }
 366}
 367
 368size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 369{
 370        size_t res;
 371        size_t oldalloc = sb->alloc;
 372
 373        strbuf_grow(sb, size);
 374        res = fread(sb->buf + sb->len, 1, size, f);
 375        if (res > 0)
 376                strbuf_setlen(sb, sb->len + res);
 377        else if (oldalloc == 0)
 378                strbuf_release(sb);
 379        return res;
 380}
 381
 382ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 383{
 384        size_t oldlen = sb->len;
 385        size_t oldalloc = sb->alloc;
 386
 387        strbuf_grow(sb, hint ? hint : 8192);
 388        for (;;) {
 389                ssize_t want = sb->alloc - sb->len - 1;
 390                ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
 391
 392                if (got < 0) {
 393                        if (oldalloc == 0)
 394                                strbuf_release(sb);
 395                        else
 396                                strbuf_setlen(sb, oldlen);
 397                        return -1;
 398                }
 399                sb->len += got;
 400                if (got < want)
 401                        break;
 402                strbuf_grow(sb, 8192);
 403        }
 404
 405        sb->buf[sb->len] = '\0';
 406        return sb->len - oldlen;
 407}
 408
 409ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
 410{
 411        size_t oldalloc = sb->alloc;
 412        ssize_t cnt;
 413
 414        strbuf_grow(sb, hint ? hint : 8192);
 415        cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 416        if (cnt > 0)
 417                strbuf_setlen(sb, sb->len + cnt);
 418        else if (oldalloc == 0)
 419                strbuf_release(sb);
 420        return cnt;
 421}
 422
 423ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 424{
 425        return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 426}
 427
 428
 429#define STRBUF_MAXLINK (2*PATH_MAX)
 430
 431int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 432{
 433        size_t oldalloc = sb->alloc;
 434
 435        if (hint < 32)
 436                hint = 32;
 437
 438        while (hint < STRBUF_MAXLINK) {
 439                int len;
 440
 441                strbuf_grow(sb, hint);
 442                len = readlink(path, sb->buf, hint);
 443                if (len < 0) {
 444                        if (errno != ERANGE)
 445                                break;
 446                } else if (len < hint) {
 447                        strbuf_setlen(sb, len);
 448                        return 0;
 449                }
 450
 451                /* .. the buffer was too small - try again */
 452                hint *= 2;
 453        }
 454        if (oldalloc == 0)
 455                strbuf_release(sb);
 456        return -1;
 457}
 458
 459int strbuf_getcwd(struct strbuf *sb)
 460{
 461        size_t oldalloc = sb->alloc;
 462        size_t guessed_len = 128;
 463
 464        for (;; guessed_len *= 2) {
 465                strbuf_grow(sb, guessed_len);
 466                if (getcwd(sb->buf, sb->alloc)) {
 467                        strbuf_setlen(sb, strlen(sb->buf));
 468                        return 0;
 469                }
 470
 471                /*
 472                 * If getcwd(3) is implemented as a syscall that falls
 473                 * back to a regular lookup using readdir(3) etc. then
 474                 * we may be able to avoid EACCES by providing enough
 475                 * space to the syscall as it's not necessarily bound
 476                 * to the same restrictions as the fallback.
 477                 */
 478                if (errno == EACCES && guessed_len < PATH_MAX)
 479                        continue;
 480
 481                if (errno != ERANGE)
 482                        break;
 483        }
 484        if (oldalloc == 0)
 485                strbuf_release(sb);
 486        else
 487                strbuf_reset(sb);
 488        return -1;
 489}
 490
 491#ifdef HAVE_GETDELIM
 492int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 493{
 494        ssize_t r;
 495
 496        if (feof(fp))
 497                return EOF;
 498
 499        strbuf_reset(sb);
 500
 501        /* Translate slopbuf to NULL, as we cannot call realloc on it */
 502        if (!sb->alloc)
 503                sb->buf = NULL;
 504        errno = 0;
 505        r = getdelim(&sb->buf, &sb->alloc, term, fp);
 506
 507        if (r > 0) {
 508                sb->len = r;
 509                return 0;
 510        }
 511        assert(r == -1);
 512
 513        /*
 514         * Normally we would have called xrealloc, which will try to free
 515         * memory and recover. But we have no way to tell getdelim() to do so.
 516         * Worse, we cannot try to recover ENOMEM ourselves, because we have
 517         * no idea how many bytes were read by getdelim.
 518         *
 519         * Dying here is reasonable. It mirrors what xrealloc would do on
 520         * catastrophic memory failure. We skip the opportunity to free pack
 521         * memory and retry, but that's unlikely to help for a malloc small
 522         * enough to hold a single line of input, anyway.
 523         */
 524        if (errno == ENOMEM)
 525                die("Out of memory, getdelim failed");
 526
 527        /*
 528         * Restore strbuf invariants; if getdelim left us with a NULL pointer,
 529         * we can just re-init, but otherwise we should make sure that our
 530         * length is empty, and that the result is NUL-terminated.
 531         */
 532        if (!sb->buf)
 533                strbuf_init(sb, 0);
 534        else
 535                strbuf_reset(sb);
 536        return EOF;
 537}
 538#else
 539int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 540{
 541        int ch;
 542
 543        if (feof(fp))
 544                return EOF;
 545
 546        strbuf_reset(sb);
 547        flockfile(fp);
 548        while ((ch = getc_unlocked(fp)) != EOF) {
 549                if (!strbuf_avail(sb))
 550                        strbuf_grow(sb, 1);
 551                sb->buf[sb->len++] = ch;
 552                if (ch == term)
 553                        break;
 554        }
 555        funlockfile(fp);
 556        if (ch == EOF && sb->len == 0)
 557                return EOF;
 558
 559        sb->buf[sb->len] = '\0';
 560        return 0;
 561}
 562#endif
 563
 564static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 565{
 566        if (strbuf_getwholeline(sb, fp, term))
 567                return EOF;
 568        if (sb->buf[sb->len - 1] == term)
 569                strbuf_setlen(sb, sb->len - 1);
 570        return 0;
 571}
 572
 573int strbuf_getline(struct strbuf *sb, FILE *fp)
 574{
 575        if (strbuf_getwholeline(sb, fp, '\n'))
 576                return EOF;
 577        if (sb->buf[sb->len - 1] == '\n') {
 578                strbuf_setlen(sb, sb->len - 1);
 579                if (sb->len && sb->buf[sb->len - 1] == '\r')
 580                        strbuf_setlen(sb, sb->len - 1);
 581        }
 582        return 0;
 583}
 584
 585int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 586{
 587        return strbuf_getdelim(sb, fp, '\n');
 588}
 589
 590int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 591{
 592        return strbuf_getdelim(sb, fp, '\0');
 593}
 594
 595int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 596{
 597        strbuf_reset(sb);
 598
 599        while (1) {
 600                char ch;
 601                ssize_t len = xread(fd, &ch, 1);
 602                if (len <= 0)
 603                        return EOF;
 604                strbuf_addch(sb, ch);
 605                if (ch == term)
 606                        break;
 607        }
 608        return 0;
 609}
 610
 611ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 612{
 613        int fd;
 614        ssize_t len;
 615        int saved_errno;
 616
 617        fd = open(path, O_RDONLY);
 618        if (fd < 0)
 619                return -1;
 620        len = strbuf_read(sb, fd, hint);
 621        saved_errno = errno;
 622        close(fd);
 623        if (len < 0) {
 624                errno = saved_errno;
 625                return -1;
 626        }
 627
 628        return len;
 629}
 630
 631void strbuf_add_lines(struct strbuf *out, const char *prefix,
 632                      const char *buf, size_t size)
 633{
 634        add_lines(out, prefix, NULL, buf, size);
 635}
 636
 637void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 638{
 639        while (*s) {
 640                size_t len = strcspn(s, "\"<>&");
 641                strbuf_add(buf, s, len);
 642                s += len;
 643                switch (*s) {
 644                case '"':
 645                        strbuf_addstr(buf, "&quot;");
 646                        break;
 647                case '<':
 648                        strbuf_addstr(buf, "&lt;");
 649                        break;
 650                case '>':
 651                        strbuf_addstr(buf, "&gt;");
 652                        break;
 653                case '&':
 654                        strbuf_addstr(buf, "&amp;");
 655                        break;
 656                case 0:
 657                        return;
 658                }
 659                s++;
 660        }
 661}
 662
 663static int is_rfc3986_reserved(char ch)
 664{
 665        switch (ch) {
 666                case '!': case '*': case '\'': case '(': case ')': case ';':
 667                case ':': case '@': case '&': case '=': case '+': case '$':
 668                case ',': case '/': case '?': case '#': case '[': case ']':
 669                        return 1;
 670        }
 671        return 0;
 672}
 673
 674static int is_rfc3986_unreserved(char ch)
 675{
 676        return isalnum(ch) ||
 677                ch == '-' || ch == '_' || ch == '.' || ch == '~';
 678}
 679
 680static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 681                                 int reserved)
 682{
 683        strbuf_grow(sb, len);
 684        while (len--) {
 685                char ch = *s++;
 686                if (is_rfc3986_unreserved(ch) ||
 687                    (!reserved && is_rfc3986_reserved(ch)))
 688                        strbuf_addch(sb, ch);
 689                else
 690                        strbuf_addf(sb, "%%%02x", (unsigned char)ch);
 691        }
 692}
 693
 694void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 695                             int reserved)
 696{
 697        strbuf_add_urlencode(sb, s, strlen(s), reserved);
 698}
 699
 700void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 701{
 702        if (bytes > 1 << 30) {
 703                strbuf_addf(buf, "%u.%2.2u GiB",
 704                            (int)(bytes >> 30),
 705                            (int)(bytes & ((1 << 30) - 1)) / 10737419);
 706        } else if (bytes > 1 << 20) {
 707                int x = bytes + 5243;  /* for rounding */
 708                strbuf_addf(buf, "%u.%2.2u MiB",
 709                            x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 710        } else if (bytes > 1 << 10) {
 711                int x = bytes + 5;  /* for rounding */
 712                strbuf_addf(buf, "%u.%2.2u KiB",
 713                            x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 714        } else {
 715                strbuf_addf(buf, "%u bytes", (int)bytes);
 716        }
 717}
 718
 719void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 720{
 721        if (!*path)
 722                die("The empty string is not a valid path");
 723        if (!is_absolute_path(path)) {
 724                struct stat cwd_stat, pwd_stat;
 725                size_t orig_len = sb->len;
 726                char *cwd = xgetcwd();
 727                char *pwd = getenv("PWD");
 728                if (pwd && strcmp(pwd, cwd) &&
 729                    !stat(cwd, &cwd_stat) &&
 730                    (cwd_stat.st_dev || cwd_stat.st_ino) &&
 731                    !stat(pwd, &pwd_stat) &&
 732                    pwd_stat.st_dev == cwd_stat.st_dev &&
 733                    pwd_stat.st_ino == cwd_stat.st_ino)
 734                        strbuf_addstr(sb, pwd);
 735                else
 736                        strbuf_addstr(sb, cwd);
 737                if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 738                        strbuf_addch(sb, '/');
 739                free(cwd);
 740        }
 741        strbuf_addstr(sb, path);
 742}
 743
 744void strbuf_add_real_path(struct strbuf *sb, const char *path)
 745{
 746        if (sb->len) {
 747                struct strbuf resolved = STRBUF_INIT;
 748                strbuf_realpath(&resolved, path, 1);
 749                strbuf_addbuf(sb, &resolved);
 750                strbuf_release(&resolved);
 751        } else
 752                strbuf_realpath(sb, path, 1);
 753}
 754
 755int printf_ln(const char *fmt, ...)
 756{
 757        int ret;
 758        va_list ap;
 759        va_start(ap, fmt);
 760        ret = vprintf(fmt, ap);
 761        va_end(ap);
 762        if (ret < 0 || putchar('\n') == EOF)
 763                return -1;
 764        return ret + 1;
 765}
 766
 767int fprintf_ln(FILE *fp, const char *fmt, ...)
 768{
 769        int ret;
 770        va_list ap;
 771        va_start(ap, fmt);
 772        ret = vfprintf(fp, fmt, ap);
 773        va_end(ap);
 774        if (ret < 0 || putc('\n', fp) == EOF)
 775                return -1;
 776        return ret + 1;
 777}
 778
 779char *xstrdup_tolower(const char *string)
 780{
 781        char *result;
 782        size_t len, i;
 783
 784        len = strlen(string);
 785        result = xmallocz(len);
 786        for (i = 0; i < len; i++)
 787                result[i] = tolower(string[i]);
 788        result[i] = '\0';
 789        return result;
 790}
 791
 792char *xstrvfmt(const char *fmt, va_list ap)
 793{
 794        struct strbuf buf = STRBUF_INIT;
 795        strbuf_vaddf(&buf, fmt, ap);
 796        return strbuf_detach(&buf, NULL);
 797}
 798
 799char *xstrfmt(const char *fmt, ...)
 800{
 801        va_list ap;
 802        char *ret;
 803
 804        va_start(ap, fmt);
 805        ret = xstrvfmt(fmt, ap);
 806        va_end(ap);
 807
 808        return ret;
 809}
 810
 811void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 812                     int tz_offset, int suppress_tz_name)
 813{
 814        struct strbuf munged_fmt = STRBUF_INIT;
 815        size_t hint = 128;
 816        size_t len;
 817
 818        if (!*fmt)
 819                return;
 820
 821        /*
 822         * There is no portable way to pass timezone information to
 823         * strftime, so we handle %z and %Z here.
 824         */
 825        for (;;) {
 826                const char *percent = strchrnul(fmt, '%');
 827                strbuf_add(&munged_fmt, fmt, percent - fmt);
 828                if (!*percent)
 829                        break;
 830                fmt = percent + 1;
 831                switch (*fmt) {
 832                case '%':
 833                        strbuf_addstr(&munged_fmt, "%%");
 834                        fmt++;
 835                        break;
 836                case 'z':
 837                        strbuf_addf(&munged_fmt, "%+05d", tz_offset);
 838                        fmt++;
 839                        break;
 840                case 'Z':
 841                        if (suppress_tz_name) {
 842                                fmt++;
 843                                break;
 844                        }
 845                        /* FALLTHROUGH */
 846                default:
 847                        strbuf_addch(&munged_fmt, '%');
 848                }
 849        }
 850        fmt = munged_fmt.buf;
 851
 852        strbuf_grow(sb, hint);
 853        len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
 854
 855        if (!len) {
 856                /*
 857                 * strftime reports "0" if it could not fit the result in the buffer.
 858                 * Unfortunately, it also reports "0" if the requested time string
 859                 * takes 0 bytes. So our strategy is to munge the format so that the
 860                 * output contains at least one character, and then drop the extra
 861                 * character before returning.
 862                 */
 863                strbuf_addch(&munged_fmt, ' ');
 864                while (!len) {
 865                        hint *= 2;
 866                        strbuf_grow(sb, hint);
 867                        len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
 868                                       munged_fmt.buf, tm);
 869                }
 870                len--; /* drop munged space */
 871        }
 872        strbuf_release(&munged_fmt);
 873        strbuf_setlen(sb, sb->len + len);
 874}
 875
 876void strbuf_add_unique_abbrev(struct strbuf *sb, const struct object_id *oid,
 877                              int abbrev_len)
 878{
 879        int r;
 880        strbuf_grow(sb, GIT_SHA1_HEXSZ + 1);
 881        r = find_unique_abbrev_r(sb->buf + sb->len, oid, abbrev_len);
 882        strbuf_setlen(sb, sb->len + r);
 883}
 884
 885/*
 886 * Returns the length of a line, without trailing spaces.
 887 *
 888 * If the line ends with newline, it will be removed too.
 889 */
 890static size_t cleanup(char *line, size_t len)
 891{
 892        while (len) {
 893                unsigned char c = line[len - 1];
 894                if (!isspace(c))
 895                        break;
 896                len--;
 897        }
 898
 899        return len;
 900}
 901
 902/*
 903 * Remove empty lines from the beginning and end
 904 * and also trailing spaces from every line.
 905 *
 906 * Turn multiple consecutive empty lines between paragraphs
 907 * into just one empty line.
 908 *
 909 * If the input has only empty lines and spaces,
 910 * no output will be produced.
 911 *
 912 * If last line does not have a newline at the end, one is added.
 913 *
 914 * Enable skip_comments to skip every line starting with comment
 915 * character.
 916 */
 917void strbuf_stripspace(struct strbuf *sb, int skip_comments)
 918{
 919        int empties = 0;
 920        size_t i, j, len, newlen;
 921        char *eol;
 922
 923        /* We may have to add a newline. */
 924        strbuf_grow(sb, 1);
 925
 926        for (i = j = 0; i < sb->len; i += len, j += newlen) {
 927                eol = memchr(sb->buf + i, '\n', sb->len - i);
 928                len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
 929
 930                if (skip_comments && len && sb->buf[i] == comment_line_char) {
 931                        newlen = 0;
 932                        continue;
 933                }
 934                newlen = cleanup(sb->buf + i, len);
 935
 936                /* Not just an empty line? */
 937                if (newlen) {
 938                        if (empties > 0 && j > 0)
 939                                sb->buf[j++] = '\n';
 940                        empties = 0;
 941                        memmove(sb->buf + j, sb->buf + i, newlen);
 942                        sb->buf[newlen + j++] = '\n';
 943                } else {
 944                        empties++;
 945                }
 946        }
 947
 948        strbuf_setlen(sb, j);
 949}
 950
 951int strbuf_normalize_path(struct strbuf *src)
 952{
 953        struct strbuf dst = STRBUF_INIT;
 954
 955        strbuf_grow(&dst, src->len);
 956        if (normalize_path_copy(dst.buf, src->buf) < 0) {
 957                strbuf_release(&dst);
 958                return -1;
 959        }
 960
 961        /*
 962         * normalize_path does not tell us the new length, so we have to
 963         * compute it by looking for the new NUL it placed
 964         */
 965        strbuf_setlen(&dst, strlen(dst.buf));
 966        strbuf_swap(src, &dst);
 967        strbuf_release(&dst);
 968        return 0;
 969}