Andrew's git / gitweb.git / strbuf.c
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strbuf.con commit refs.c: make get_main_ref_store() public and use it (077be78)
   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
  14/*
  15 * Used as the default ->buf value, so that people can always assume
  16 * buf is non NULL and ->buf is NUL terminated even for a freshly
  17 * initialized strbuf.
  18 */
  19char strbuf_slopbuf[1];
  20
  21void strbuf_init(struct strbuf *sb, size_t hint)
  22{
  23        sb->alloc = sb->len = 0;
  24        sb->buf = strbuf_slopbuf;
  25        if (hint)
  26                strbuf_grow(sb, hint);
  27}
  28
  29void strbuf_release(struct strbuf *sb)
  30{
  31        if (sb->alloc) {
  32                free(sb->buf);
  33                strbuf_init(sb, 0);
  34        }
  35}
  36
  37char *strbuf_detach(struct strbuf *sb, size_t *sz)
  38{
  39        char *res;
  40        strbuf_grow(sb, 0);
  41        res = sb->buf;
  42        if (sz)
  43                *sz = sb->len;
  44        strbuf_init(sb, 0);
  45        return res;
  46}
  47
  48void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  49{
  50        strbuf_release(sb);
  51        sb->buf   = buf;
  52        sb->len   = len;
  53        sb->alloc = alloc;
  54        strbuf_grow(sb, 0);
  55        sb->buf[sb->len] = '\0';
  56}
  57
  58void strbuf_grow(struct strbuf *sb, size_t extra)
  59{
  60        int new_buf = !sb->alloc;
  61        if (unsigned_add_overflows(extra, 1) ||
  62            unsigned_add_overflows(sb->len, extra + 1))
  63                die("you want to use way too much memory");
  64        if (new_buf)
  65                sb->buf = NULL;
  66        ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  67        if (new_buf)
  68                sb->buf[0] = '\0';
  69}
  70
  71void strbuf_trim(struct strbuf *sb)
  72{
  73        strbuf_rtrim(sb);
  74        strbuf_ltrim(sb);
  75}
  76void strbuf_rtrim(struct strbuf *sb)
  77{
  78        while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  79                sb->len--;
  80        sb->buf[sb->len] = '\0';
  81}
  82
  83void strbuf_ltrim(struct strbuf *sb)
  84{
  85        char *b = sb->buf;
  86        while (sb->len > 0 && isspace(*b)) {
  87                b++;
  88                sb->len--;
  89        }
  90        memmove(sb->buf, b, sb->len);
  91        sb->buf[sb->len] = '\0';
  92}
  93
  94int strbuf_reencode(struct strbuf *sb, const char *from, const char *to)
  95{
  96        char *out;
  97        int len;
  98
  99        if (same_encoding(from, to))
 100                return 0;
 101
 102        out = reencode_string_len(sb->buf, sb->len, to, from, &len);
 103        if (!out)
 104                return -1;
 105
 106        strbuf_attach(sb, out, len, len);
 107        return 0;
 108}
 109
 110void strbuf_tolower(struct strbuf *sb)
 111{
 112        char *p = sb->buf, *end = sb->buf + sb->len;
 113        for (; p < end; p++)
 114                *p = tolower(*p);
 115}
 116
 117struct strbuf **strbuf_split_buf(const char *str, size_t slen,
 118                                 int terminator, int max)
 119{
 120        struct strbuf **ret = NULL;
 121        size_t nr = 0, alloc = 0;
 122        struct strbuf *t;
 123
 124        while (slen) {
 125                int len = slen;
 126                if (max <= 0 || nr + 1 < max) {
 127                        const char *end = memchr(str, terminator, slen);
 128                        if (end)
 129                                len = end - str + 1;
 130                }
 131                t = xmalloc(sizeof(struct strbuf));
 132                strbuf_init(t, len);
 133                strbuf_add(t, str, len);
 134                ALLOC_GROW(ret, nr + 2, alloc);
 135                ret[nr++] = t;
 136                str += len;
 137                slen -= len;
 138        }
 139        ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 140        ret[nr] = NULL;
 141        return ret;
 142}
 143
 144void strbuf_list_free(struct strbuf **sbs)
 145{
 146        struct strbuf **s = sbs;
 147
 148        while (*s) {
 149                strbuf_release(*s);
 150                free(*s++);
 151        }
 152        free(sbs);
 153}
 154
 155int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 156{
 157        int len = a->len < b->len ? a->len: b->len;
 158        int cmp = memcmp(a->buf, b->buf, len);
 159        if (cmp)
 160                return cmp;
 161        return a->len < b->len ? -1: a->len != b->len;
 162}
 163
 164void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 165                                   const void *data, size_t dlen)
 166{
 167        if (unsigned_add_overflows(pos, len))
 168                die("you want to use way too much memory");
 169        if (pos > sb->len)
 170                die("`pos' is too far after the end of the buffer");
 171        if (pos + len > sb->len)
 172                die("`pos + len' is too far after the end of the buffer");
 173
 174        if (dlen >= len)
 175                strbuf_grow(sb, dlen - len);
 176        memmove(sb->buf + pos + dlen,
 177                        sb->buf + pos + len,
 178                        sb->len - pos - len);
 179        memcpy(sb->buf + pos, data, dlen);
 180        strbuf_setlen(sb, sb->len + dlen - len);
 181}
 182
 183void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 184{
 185        strbuf_splice(sb, pos, 0, data, len);
 186}
 187
 188void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 189{
 190        strbuf_splice(sb, pos, len, "", 0);
 191}
 192
 193void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 194{
 195        strbuf_grow(sb, len);
 196        memcpy(sb->buf + sb->len, data, len);
 197        strbuf_setlen(sb, sb->len + len);
 198}
 199
 200void strbuf_addbuf(struct strbuf *sb, const struct strbuf *sb2)
 201{
 202        strbuf_grow(sb, sb2->len);
 203        memcpy(sb->buf + sb->len, sb2->buf, sb2->len);
 204        strbuf_setlen(sb, sb->len + sb2->len);
 205}
 206
 207void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 208{
 209        strbuf_grow(sb, len);
 210        memcpy(sb->buf + sb->len, sb->buf + pos, len);
 211        strbuf_setlen(sb, sb->len + len);
 212}
 213
 214void strbuf_addchars(struct strbuf *sb, int c, size_t n)
 215{
 216        strbuf_grow(sb, n);
 217        memset(sb->buf + sb->len, c, n);
 218        strbuf_setlen(sb, sb->len + n);
 219}
 220
 221void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 222{
 223        va_list ap;
 224        va_start(ap, fmt);
 225        strbuf_vaddf(sb, fmt, ap);
 226        va_end(ap);
 227}
 228
 229static void add_lines(struct strbuf *out,
 230                        const char *prefix1,
 231                        const char *prefix2,
 232                        const char *buf, size_t size)
 233{
 234        while (size) {
 235                const char *prefix;
 236                const char *next = memchr(buf, '\n', size);
 237                next = next ? (next + 1) : (buf + size);
 238
 239                prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
 240                          ? prefix2 : prefix1);
 241                strbuf_addstr(out, prefix);
 242                strbuf_add(out, buf, next - buf);
 243                size -= next - buf;
 244                buf = next;
 245        }
 246        strbuf_complete_line(out);
 247}
 248
 249void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 250{
 251        static char prefix1[3];
 252        static char prefix2[2];
 253
 254        if (prefix1[0] != comment_line_char) {
 255                xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
 256                xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
 257        }
 258        add_lines(out, prefix1, prefix2, buf, size);
 259}
 260
 261void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 262{
 263        va_list params;
 264        struct strbuf buf = STRBUF_INIT;
 265        int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 266
 267        va_start(params, fmt);
 268        strbuf_vaddf(&buf, fmt, params);
 269        va_end(params);
 270
 271        strbuf_add_commented_lines(sb, buf.buf, buf.len);
 272        if (incomplete_line)
 273                sb->buf[--sb->len] = '\0';
 274
 275        strbuf_release(&buf);
 276}
 277
 278void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 279{
 280        int len;
 281        va_list cp;
 282
 283        if (!strbuf_avail(sb))
 284                strbuf_grow(sb, 64);
 285        va_copy(cp, ap);
 286        len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 287        va_end(cp);
 288        if (len < 0)
 289                die("BUG: your vsnprintf is broken (returned %d)", len);
 290        if (len > strbuf_avail(sb)) {
 291                strbuf_grow(sb, len);
 292                len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 293                if (len > strbuf_avail(sb))
 294                        die("BUG: your vsnprintf is broken (insatiable)");
 295        }
 296        strbuf_setlen(sb, sb->len + len);
 297}
 298
 299void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 300                   void *context)
 301{
 302        for (;;) {
 303                const char *percent;
 304                size_t consumed;
 305
 306                percent = strchrnul(format, '%');
 307                strbuf_add(sb, format, percent - format);
 308                if (!*percent)
 309                        break;
 310                format = percent + 1;
 311
 312                if (*format == '%') {
 313                        strbuf_addch(sb, '%');
 314                        format++;
 315                        continue;
 316                }
 317
 318                consumed = fn(sb, format, context);
 319                if (consumed)
 320                        format += consumed;
 321                else
 322                        strbuf_addch(sb, '%');
 323        }
 324}
 325
 326size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 327                void *context)
 328{
 329        struct strbuf_expand_dict_entry *e = context;
 330        size_t len;
 331
 332        for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 333                if (!strncmp(placeholder, e->placeholder, len)) {
 334                        if (e->value)
 335                                strbuf_addstr(sb, e->value);
 336                        return len;
 337                }
 338        }
 339        return 0;
 340}
 341
 342void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 343{
 344        int i, len = src->len;
 345
 346        for (i = 0; i < len; i++) {
 347                if (src->buf[i] == '%')
 348                        strbuf_addch(dst, '%');
 349                strbuf_addch(dst, src->buf[i]);
 350        }
 351}
 352
 353size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 354{
 355        size_t res;
 356        size_t oldalloc = sb->alloc;
 357
 358        strbuf_grow(sb, size);
 359        res = fread(sb->buf + sb->len, 1, size, f);
 360        if (res > 0)
 361                strbuf_setlen(sb, sb->len + res);
 362        else if (oldalloc == 0)
 363                strbuf_release(sb);
 364        return res;
 365}
 366
 367ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 368{
 369        size_t oldlen = sb->len;
 370        size_t oldalloc = sb->alloc;
 371
 372        strbuf_grow(sb, hint ? hint : 8192);
 373        for (;;) {
 374                ssize_t want = sb->alloc - sb->len - 1;
 375                ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
 376
 377                if (got < 0) {
 378                        if (oldalloc == 0)
 379                                strbuf_release(sb);
 380                        else
 381                                strbuf_setlen(sb, oldlen);
 382                        return -1;
 383                }
 384                sb->len += got;
 385                if (got < want)
 386                        break;
 387                strbuf_grow(sb, 8192);
 388        }
 389
 390        sb->buf[sb->len] = '\0';
 391        return sb->len - oldlen;
 392}
 393
 394ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
 395{
 396        ssize_t cnt;
 397
 398        strbuf_grow(sb, hint ? hint : 8192);
 399        cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 400        if (cnt > 0)
 401                strbuf_setlen(sb, sb->len + cnt);
 402        return cnt;
 403}
 404
 405ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 406{
 407        return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 408}
 409
 410
 411#define STRBUF_MAXLINK (2*PATH_MAX)
 412
 413int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 414{
 415        size_t oldalloc = sb->alloc;
 416
 417        if (hint < 32)
 418                hint = 32;
 419
 420        while (hint < STRBUF_MAXLINK) {
 421                int len;
 422
 423                strbuf_grow(sb, hint);
 424                len = readlink(path, sb->buf, hint);
 425                if (len < 0) {
 426                        if (errno != ERANGE)
 427                                break;
 428                } else if (len < hint) {
 429                        strbuf_setlen(sb, len);
 430                        return 0;
 431                }
 432
 433                /* .. the buffer was too small - try again */
 434                hint *= 2;
 435        }
 436        if (oldalloc == 0)
 437                strbuf_release(sb);
 438        return -1;
 439}
 440
 441int strbuf_getcwd(struct strbuf *sb)
 442{
 443        size_t oldalloc = sb->alloc;
 444        size_t guessed_len = 128;
 445
 446        for (;; guessed_len *= 2) {
 447                strbuf_grow(sb, guessed_len);
 448                if (getcwd(sb->buf, sb->alloc)) {
 449                        strbuf_setlen(sb, strlen(sb->buf));
 450                        return 0;
 451                }
 452                if (errno != ERANGE)
 453                        break;
 454        }
 455        if (oldalloc == 0)
 456                strbuf_release(sb);
 457        else
 458                strbuf_reset(sb);
 459        return -1;
 460}
 461
 462#ifdef HAVE_GETDELIM
 463int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 464{
 465        ssize_t r;
 466
 467        if (feof(fp))
 468                return EOF;
 469
 470        strbuf_reset(sb);
 471
 472        /* Translate slopbuf to NULL, as we cannot call realloc on it */
 473        if (!sb->alloc)
 474                sb->buf = NULL;
 475        r = getdelim(&sb->buf, &sb->alloc, term, fp);
 476
 477        if (r > 0) {
 478                sb->len = r;
 479                return 0;
 480        }
 481        assert(r == -1);
 482
 483        /*
 484         * Normally we would have called xrealloc, which will try to free
 485         * memory and recover. But we have no way to tell getdelim() to do so.
 486         * Worse, we cannot try to recover ENOMEM ourselves, because we have
 487         * no idea how many bytes were read by getdelim.
 488         *
 489         * Dying here is reasonable. It mirrors what xrealloc would do on
 490         * catastrophic memory failure. We skip the opportunity to free pack
 491         * memory and retry, but that's unlikely to help for a malloc small
 492         * enough to hold a single line of input, anyway.
 493         */
 494        if (errno == ENOMEM)
 495                die("Out of memory, getdelim failed");
 496
 497        /*
 498         * Restore strbuf invariants; if getdelim left us with a NULL pointer,
 499         * we can just re-init, but otherwise we should make sure that our
 500         * length is empty, and that the result is NUL-terminated.
 501         */
 502        if (!sb->buf)
 503                strbuf_init(sb, 0);
 504        else
 505                strbuf_reset(sb);
 506        return EOF;
 507}
 508#else
 509int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 510{
 511        int ch;
 512
 513        if (feof(fp))
 514                return EOF;
 515
 516        strbuf_reset(sb);
 517        flockfile(fp);
 518        while ((ch = getc_unlocked(fp)) != EOF) {
 519                if (!strbuf_avail(sb))
 520                        strbuf_grow(sb, 1);
 521                sb->buf[sb->len++] = ch;
 522                if (ch == term)
 523                        break;
 524        }
 525        funlockfile(fp);
 526        if (ch == EOF && sb->len == 0)
 527                return EOF;
 528
 529        sb->buf[sb->len] = '\0';
 530        return 0;
 531}
 532#endif
 533
 534static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 535{
 536        if (strbuf_getwholeline(sb, fp, term))
 537                return EOF;
 538        if (sb->buf[sb->len - 1] == term)
 539                strbuf_setlen(sb, sb->len - 1);
 540        return 0;
 541}
 542
 543int strbuf_getline(struct strbuf *sb, FILE *fp)
 544{
 545        if (strbuf_getwholeline(sb, fp, '\n'))
 546                return EOF;
 547        if (sb->buf[sb->len - 1] == '\n') {
 548                strbuf_setlen(sb, sb->len - 1);
 549                if (sb->len && sb->buf[sb->len - 1] == '\r')
 550                        strbuf_setlen(sb, sb->len - 1);
 551        }
 552        return 0;
 553}
 554
 555int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 556{
 557        return strbuf_getdelim(sb, fp, '\n');
 558}
 559
 560int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 561{
 562        return strbuf_getdelim(sb, fp, '\0');
 563}
 564
 565int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 566{
 567        strbuf_reset(sb);
 568
 569        while (1) {
 570                char ch;
 571                ssize_t len = xread(fd, &ch, 1);
 572                if (len <= 0)
 573                        return EOF;
 574                strbuf_addch(sb, ch);
 575                if (ch == term)
 576                        break;
 577        }
 578        return 0;
 579}
 580
 581ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 582{
 583        int fd;
 584        ssize_t len;
 585
 586        fd = open(path, O_RDONLY);
 587        if (fd < 0)
 588                return -1;
 589        len = strbuf_read(sb, fd, hint);
 590        close(fd);
 591        if (len < 0)
 592                return -1;
 593
 594        return len;
 595}
 596
 597void strbuf_add_lines(struct strbuf *out, const char *prefix,
 598                      const char *buf, size_t size)
 599{
 600        add_lines(out, prefix, NULL, buf, size);
 601}
 602
 603void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 604{
 605        while (*s) {
 606                size_t len = strcspn(s, "\"<>&");
 607                strbuf_add(buf, s, len);
 608                s += len;
 609                switch (*s) {
 610                case '"':
 611                        strbuf_addstr(buf, "&quot;");
 612                        break;
 613                case '<':
 614                        strbuf_addstr(buf, "&lt;");
 615                        break;
 616                case '>':
 617                        strbuf_addstr(buf, "&gt;");
 618                        break;
 619                case '&':
 620                        strbuf_addstr(buf, "&amp;");
 621                        break;
 622                case 0:
 623                        return;
 624                }
 625                s++;
 626        }
 627}
 628
 629static int is_rfc3986_reserved(char ch)
 630{
 631        switch (ch) {
 632                case '!': case '*': case '\'': case '(': case ')': case ';':
 633                case ':': case '@': case '&': case '=': case '+': case '$':
 634                case ',': case '/': case '?': case '#': case '[': case ']':
 635                        return 1;
 636        }
 637        return 0;
 638}
 639
 640static int is_rfc3986_unreserved(char ch)
 641{
 642        return isalnum(ch) ||
 643                ch == '-' || ch == '_' || ch == '.' || ch == '~';
 644}
 645
 646static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 647                                 int reserved)
 648{
 649        strbuf_grow(sb, len);
 650        while (len--) {
 651                char ch = *s++;
 652                if (is_rfc3986_unreserved(ch) ||
 653                    (!reserved && is_rfc3986_reserved(ch)))
 654                        strbuf_addch(sb, ch);
 655                else
 656                        strbuf_addf(sb, "%%%02x", ch);
 657        }
 658}
 659
 660void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 661                             int reserved)
 662{
 663        strbuf_add_urlencode(sb, s, strlen(s), reserved);
 664}
 665
 666void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 667{
 668        if (bytes > 1 << 30) {
 669                strbuf_addf(buf, "%u.%2.2u GiB",
 670                            (int)(bytes >> 30),
 671                            (int)(bytes & ((1 << 30) - 1)) / 10737419);
 672        } else if (bytes > 1 << 20) {
 673                int x = bytes + 5243;  /* for rounding */
 674                strbuf_addf(buf, "%u.%2.2u MiB",
 675                            x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 676        } else if (bytes > 1 << 10) {
 677                int x = bytes + 5;  /* for rounding */
 678                strbuf_addf(buf, "%u.%2.2u KiB",
 679                            x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 680        } else {
 681                strbuf_addf(buf, "%u bytes", (int)bytes);
 682        }
 683}
 684
 685void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 686{
 687        if (!*path)
 688                die("The empty string is not a valid path");
 689        if (!is_absolute_path(path)) {
 690                struct stat cwd_stat, pwd_stat;
 691                size_t orig_len = sb->len;
 692                char *cwd = xgetcwd();
 693                char *pwd = getenv("PWD");
 694                if (pwd && strcmp(pwd, cwd) &&
 695                    !stat(cwd, &cwd_stat) &&
 696                    (cwd_stat.st_dev || cwd_stat.st_ino) &&
 697                    !stat(pwd, &pwd_stat) &&
 698                    pwd_stat.st_dev == cwd_stat.st_dev &&
 699                    pwd_stat.st_ino == cwd_stat.st_ino)
 700                        strbuf_addstr(sb, pwd);
 701                else
 702                        strbuf_addstr(sb, cwd);
 703                if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 704                        strbuf_addch(sb, '/');
 705                free(cwd);
 706        }
 707        strbuf_addstr(sb, path);
 708}
 709
 710void strbuf_add_real_path(struct strbuf *sb, const char *path)
 711{
 712        if (sb->len) {
 713                struct strbuf resolved = STRBUF_INIT;
 714                strbuf_realpath(&resolved, path, 1);
 715                strbuf_addbuf(sb, &resolved);
 716                strbuf_release(&resolved);
 717        } else
 718                strbuf_realpath(sb, path, 1);
 719}
 720
 721int printf_ln(const char *fmt, ...)
 722{
 723        int ret;
 724        va_list ap;
 725        va_start(ap, fmt);
 726        ret = vprintf(fmt, ap);
 727        va_end(ap);
 728        if (ret < 0 || putchar('\n') == EOF)
 729                return -1;
 730        return ret + 1;
 731}
 732
 733int fprintf_ln(FILE *fp, const char *fmt, ...)
 734{
 735        int ret;
 736        va_list ap;
 737        va_start(ap, fmt);
 738        ret = vfprintf(fp, fmt, ap);
 739        va_end(ap);
 740        if (ret < 0 || putc('\n', fp) == EOF)
 741                return -1;
 742        return ret + 1;
 743}
 744
 745char *xstrdup_tolower(const char *string)
 746{
 747        char *result;
 748        size_t len, i;
 749
 750        len = strlen(string);
 751        result = xmallocz(len);
 752        for (i = 0; i < len; i++)
 753                result[i] = tolower(string[i]);
 754        result[i] = '\0';
 755        return result;
 756}
 757
 758char *xstrvfmt(const char *fmt, va_list ap)
 759{
 760        struct strbuf buf = STRBUF_INIT;
 761        strbuf_vaddf(&buf, fmt, ap);
 762        return strbuf_detach(&buf, NULL);
 763}
 764
 765char *xstrfmt(const char *fmt, ...)
 766{
 767        va_list ap;
 768        char *ret;
 769
 770        va_start(ap, fmt);
 771        ret = xstrvfmt(fmt, ap);
 772        va_end(ap);
 773
 774        return ret;
 775}
 776
 777void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm)
 778{
 779        size_t hint = 128;
 780        size_t len;
 781
 782        if (!*fmt)
 783                return;
 784
 785        strbuf_grow(sb, hint);
 786        len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
 787
 788        if (!len) {
 789                /*
 790                 * strftime reports "0" if it could not fit the result in the buffer.
 791                 * Unfortunately, it also reports "0" if the requested time string
 792                 * takes 0 bytes. So our strategy is to munge the format so that the
 793                 * output contains at least one character, and then drop the extra
 794                 * character before returning.
 795                 */
 796                struct strbuf munged_fmt = STRBUF_INIT;
 797                strbuf_addf(&munged_fmt, "%s ", fmt);
 798                while (!len) {
 799                        hint *= 2;
 800                        strbuf_grow(sb, hint);
 801                        len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
 802                                       munged_fmt.buf, tm);
 803                }
 804                strbuf_release(&munged_fmt);
 805                len--; /* drop munged space */
 806        }
 807        strbuf_setlen(sb, sb->len + len);
 808}
 809
 810void strbuf_add_unique_abbrev(struct strbuf *sb, const unsigned char *sha1,
 811                              int abbrev_len)
 812{
 813        int r;
 814        strbuf_grow(sb, GIT_SHA1_HEXSZ + 1);
 815        r = find_unique_abbrev_r(sb->buf + sb->len, sha1, abbrev_len);
 816        strbuf_setlen(sb, sb->len + r);
 817}
 818
 819/*
 820 * Returns the length of a line, without trailing spaces.
 821 *
 822 * If the line ends with newline, it will be removed too.
 823 */
 824static size_t cleanup(char *line, size_t len)
 825{
 826        while (len) {
 827                unsigned char c = line[len - 1];
 828                if (!isspace(c))
 829                        break;
 830                len--;
 831        }
 832
 833        return len;
 834}
 835
 836/*
 837 * Remove empty lines from the beginning and end
 838 * and also trailing spaces from every line.
 839 *
 840 * Turn multiple consecutive empty lines between paragraphs
 841 * into just one empty line.
 842 *
 843 * If the input has only empty lines and spaces,
 844 * no output will be produced.
 845 *
 846 * If last line does not have a newline at the end, one is added.
 847 *
 848 * Enable skip_comments to skip every line starting with comment
 849 * character.
 850 */
 851void strbuf_stripspace(struct strbuf *sb, int skip_comments)
 852{
 853        int empties = 0;
 854        size_t i, j, len, newlen;
 855        char *eol;
 856
 857        /* We may have to add a newline. */
 858        strbuf_grow(sb, 1);
 859
 860        for (i = j = 0; i < sb->len; i += len, j += newlen) {
 861                eol = memchr(sb->buf + i, '\n', sb->len - i);
 862                len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
 863
 864                if (skip_comments && len && sb->buf[i] == comment_line_char) {
 865                        newlen = 0;
 866                        continue;
 867                }
 868                newlen = cleanup(sb->buf + i, len);
 869
 870                /* Not just an empty line? */
 871                if (newlen) {
 872                        if (empties > 0 && j > 0)
 873                                sb->buf[j++] = '\n';
 874                        empties = 0;
 875                        memmove(sb->buf + j, sb->buf + i, newlen);
 876                        sb->buf[newlen + j++] = '\n';
 877                } else {
 878                        empties++;
 879                }
 880        }
 881
 882        strbuf_setlen(sb, j);
 883}
 884
 885int strbuf_normalize_path(struct strbuf *src)
 886{
 887        struct strbuf dst = STRBUF_INIT;
 888
 889        strbuf_grow(&dst, src->len);
 890        if (normalize_path_copy(dst.buf, src->buf) < 0) {
 891                strbuf_release(&dst);
 892                return -1;
 893        }
 894
 895        /*
 896         * normalize_path does not tell us the new length, so we have to
 897         * compute it by looking for the new NUL it placed
 898         */
 899        strbuf_setlen(&dst, strlen(dst.buf));
 900        strbuf_swap(src, &dst);
 901        strbuf_release(&dst);
 902        return 0;
 903}