Andrew's git / gitweb.git / strbuf.c
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strbuf.con commit submodule: ignore trailing slash on superproject URL (0878850)
   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, NULL, 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_adddup(struct strbuf *sb, size_t pos, size_t len)
 201{
 202        strbuf_grow(sb, len);
 203        memcpy(sb->buf + sb->len, sb->buf + pos, len);
 204        strbuf_setlen(sb, sb->len + len);
 205}
 206
 207void strbuf_addchars(struct strbuf *sb, int c, size_t n)
 208{
 209        strbuf_grow(sb, n);
 210        memset(sb->buf + sb->len, c, n);
 211        strbuf_setlen(sb, sb->len + n);
 212}
 213
 214void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 215{
 216        va_list ap;
 217        va_start(ap, fmt);
 218        strbuf_vaddf(sb, fmt, ap);
 219        va_end(ap);
 220}
 221
 222static void add_lines(struct strbuf *out,
 223                        const char *prefix1,
 224                        const char *prefix2,
 225                        const char *buf, size_t size)
 226{
 227        while (size) {
 228                const char *prefix;
 229                const char *next = memchr(buf, '\n', size);
 230                next = next ? (next + 1) : (buf + size);
 231
 232                prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
 233                          ? prefix2 : prefix1);
 234                strbuf_addstr(out, prefix);
 235                strbuf_add(out, buf, next - buf);
 236                size -= next - buf;
 237                buf = next;
 238        }
 239        strbuf_complete_line(out);
 240}
 241
 242void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 243{
 244        static char prefix1[3];
 245        static char prefix2[2];
 246
 247        if (prefix1[0] != comment_line_char) {
 248                xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
 249                xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
 250        }
 251        add_lines(out, prefix1, prefix2, buf, size);
 252}
 253
 254void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 255{
 256        va_list params;
 257        struct strbuf buf = STRBUF_INIT;
 258        int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 259
 260        va_start(params, fmt);
 261        strbuf_vaddf(&buf, fmt, params);
 262        va_end(params);
 263
 264        strbuf_add_commented_lines(sb, buf.buf, buf.len);
 265        if (incomplete_line)
 266                sb->buf[--sb->len] = '\0';
 267
 268        strbuf_release(&buf);
 269}
 270
 271void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 272{
 273        int len;
 274        va_list cp;
 275
 276        if (!strbuf_avail(sb))
 277                strbuf_grow(sb, 64);
 278        va_copy(cp, ap);
 279        len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 280        va_end(cp);
 281        if (len < 0)
 282                die("BUG: your vsnprintf is broken (returned %d)", len);
 283        if (len > strbuf_avail(sb)) {
 284                strbuf_grow(sb, len);
 285                len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 286                if (len > strbuf_avail(sb))
 287                        die("BUG: your vsnprintf is broken (insatiable)");
 288        }
 289        strbuf_setlen(sb, sb->len + len);
 290}
 291
 292void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 293                   void *context)
 294{
 295        for (;;) {
 296                const char *percent;
 297                size_t consumed;
 298
 299                percent = strchrnul(format, '%');
 300                strbuf_add(sb, format, percent - format);
 301                if (!*percent)
 302                        break;
 303                format = percent + 1;
 304
 305                if (*format == '%') {
 306                        strbuf_addch(sb, '%');
 307                        format++;
 308                        continue;
 309                }
 310
 311                consumed = fn(sb, format, context);
 312                if (consumed)
 313                        format += consumed;
 314                else
 315                        strbuf_addch(sb, '%');
 316        }
 317}
 318
 319size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 320                void *context)
 321{
 322        struct strbuf_expand_dict_entry *e = context;
 323        size_t len;
 324
 325        for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 326                if (!strncmp(placeholder, e->placeholder, len)) {
 327                        if (e->value)
 328                                strbuf_addstr(sb, e->value);
 329                        return len;
 330                }
 331        }
 332        return 0;
 333}
 334
 335void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 336{
 337        int i, len = src->len;
 338
 339        for (i = 0; i < len; i++) {
 340                if (src->buf[i] == '%')
 341                        strbuf_addch(dst, '%');
 342                strbuf_addch(dst, src->buf[i]);
 343        }
 344}
 345
 346size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 347{
 348        size_t res;
 349        size_t oldalloc = sb->alloc;
 350
 351        strbuf_grow(sb, size);
 352        res = fread(sb->buf + sb->len, 1, size, f);
 353        if (res > 0)
 354                strbuf_setlen(sb, sb->len + res);
 355        else if (oldalloc == 0)
 356                strbuf_release(sb);
 357        return res;
 358}
 359
 360ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 361{
 362        size_t oldlen = sb->len;
 363        size_t oldalloc = sb->alloc;
 364
 365        strbuf_grow(sb, hint ? hint : 8192);
 366        for (;;) {
 367                ssize_t want = sb->alloc - sb->len - 1;
 368                ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
 369
 370                if (got < 0) {
 371                        if (oldalloc == 0)
 372                                strbuf_release(sb);
 373                        else
 374                                strbuf_setlen(sb, oldlen);
 375                        return -1;
 376                }
 377                sb->len += got;
 378                if (got < want)
 379                        break;
 380                strbuf_grow(sb, 8192);
 381        }
 382
 383        sb->buf[sb->len] = '\0';
 384        return sb->len - oldlen;
 385}
 386
 387ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
 388{
 389        ssize_t cnt;
 390
 391        strbuf_grow(sb, hint ? hint : 8192);
 392        cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 393        if (cnt > 0)
 394                strbuf_setlen(sb, sb->len + cnt);
 395        return cnt;
 396}
 397
 398ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 399{
 400        return sb->len ? fwrite(sb->buf, 1, sb->len, f) : 0;
 401}
 402
 403
 404#define STRBUF_MAXLINK (2*PATH_MAX)
 405
 406int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 407{
 408        size_t oldalloc = sb->alloc;
 409
 410        if (hint < 32)
 411                hint = 32;
 412
 413        while (hint < STRBUF_MAXLINK) {
 414                int len;
 415
 416                strbuf_grow(sb, hint);
 417                len = readlink(path, sb->buf, hint);
 418                if (len < 0) {
 419                        if (errno != ERANGE)
 420                                break;
 421                } else if (len < hint) {
 422                        strbuf_setlen(sb, len);
 423                        return 0;
 424                }
 425
 426                /* .. the buffer was too small - try again */
 427                hint *= 2;
 428        }
 429        if (oldalloc == 0)
 430                strbuf_release(sb);
 431        return -1;
 432}
 433
 434int strbuf_getcwd(struct strbuf *sb)
 435{
 436        size_t oldalloc = sb->alloc;
 437        size_t guessed_len = 128;
 438
 439        for (;; guessed_len *= 2) {
 440                strbuf_grow(sb, guessed_len);
 441                if (getcwd(sb->buf, sb->alloc)) {
 442                        strbuf_setlen(sb, strlen(sb->buf));
 443                        return 0;
 444                }
 445                if (errno != ERANGE)
 446                        break;
 447        }
 448        if (oldalloc == 0)
 449                strbuf_release(sb);
 450        else
 451                strbuf_reset(sb);
 452        return -1;
 453}
 454
 455#ifdef HAVE_GETDELIM
 456int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 457{
 458        ssize_t r;
 459
 460        if (feof(fp))
 461                return EOF;
 462
 463        strbuf_reset(sb);
 464
 465        /* Translate slopbuf to NULL, as we cannot call realloc on it */
 466        if (!sb->alloc)
 467                sb->buf = NULL;
 468        r = getdelim(&sb->buf, &sb->alloc, term, fp);
 469
 470        if (r > 0) {
 471                sb->len = r;
 472                return 0;
 473        }
 474        assert(r == -1);
 475
 476        /*
 477         * Normally we would have called xrealloc, which will try to free
 478         * memory and recover. But we have no way to tell getdelim() to do so.
 479         * Worse, we cannot try to recover ENOMEM ourselves, because we have
 480         * no idea how many bytes were read by getdelim.
 481         *
 482         * Dying here is reasonable. It mirrors what xrealloc would do on
 483         * catastrophic memory failure. We skip the opportunity to free pack
 484         * memory and retry, but that's unlikely to help for a malloc small
 485         * enough to hold a single line of input, anyway.
 486         */
 487        if (errno == ENOMEM)
 488                die("Out of memory, getdelim failed");
 489
 490        /* Restore slopbuf that we moved out of the way before */
 491        if (!sb->buf)
 492                strbuf_init(sb, 0);
 493        return EOF;
 494}
 495#else
 496int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 497{
 498        int ch;
 499
 500        if (feof(fp))
 501                return EOF;
 502
 503        strbuf_reset(sb);
 504        flockfile(fp);
 505        while ((ch = getc_unlocked(fp)) != EOF) {
 506                if (!strbuf_avail(sb))
 507                        strbuf_grow(sb, 1);
 508                sb->buf[sb->len++] = ch;
 509                if (ch == term)
 510                        break;
 511        }
 512        funlockfile(fp);
 513        if (ch == EOF && sb->len == 0)
 514                return EOF;
 515
 516        sb->buf[sb->len] = '\0';
 517        return 0;
 518}
 519#endif
 520
 521static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 522{
 523        if (strbuf_getwholeline(sb, fp, term))
 524                return EOF;
 525        if (sb->buf[sb->len - 1] == term)
 526                strbuf_setlen(sb, sb->len - 1);
 527        return 0;
 528}
 529
 530int strbuf_getline(struct strbuf *sb, FILE *fp)
 531{
 532        if (strbuf_getwholeline(sb, fp, '\n'))
 533                return EOF;
 534        if (sb->buf[sb->len - 1] == '\n') {
 535                strbuf_setlen(sb, sb->len - 1);
 536                if (sb->len && sb->buf[sb->len - 1] == '\r')
 537                        strbuf_setlen(sb, sb->len - 1);
 538        }
 539        return 0;
 540}
 541
 542int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 543{
 544        return strbuf_getdelim(sb, fp, '\n');
 545}
 546
 547int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 548{
 549        return strbuf_getdelim(sb, fp, '\0');
 550}
 551
 552int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 553{
 554        strbuf_reset(sb);
 555
 556        while (1) {
 557                char ch;
 558                ssize_t len = xread(fd, &ch, 1);
 559                if (len <= 0)
 560                        return EOF;
 561                strbuf_addch(sb, ch);
 562                if (ch == term)
 563                        break;
 564        }
 565        return 0;
 566}
 567
 568ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 569{
 570        int fd;
 571        ssize_t len;
 572
 573        fd = open(path, O_RDONLY);
 574        if (fd < 0)
 575                return -1;
 576        len = strbuf_read(sb, fd, hint);
 577        close(fd);
 578        if (len < 0)
 579                return -1;
 580
 581        return len;
 582}
 583
 584void strbuf_add_lines(struct strbuf *out, const char *prefix,
 585                      const char *buf, size_t size)
 586{
 587        add_lines(out, prefix, NULL, buf, size);
 588}
 589
 590void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 591{
 592        while (*s) {
 593                size_t len = strcspn(s, "\"<>&");
 594                strbuf_add(buf, s, len);
 595                s += len;
 596                switch (*s) {
 597                case '"':
 598                        strbuf_addstr(buf, "&quot;");
 599                        break;
 600                case '<':
 601                        strbuf_addstr(buf, "&lt;");
 602                        break;
 603                case '>':
 604                        strbuf_addstr(buf, "&gt;");
 605                        break;
 606                case '&':
 607                        strbuf_addstr(buf, "&amp;");
 608                        break;
 609                case 0:
 610                        return;
 611                }
 612                s++;
 613        }
 614}
 615
 616static int is_rfc3986_reserved(char ch)
 617{
 618        switch (ch) {
 619                case '!': case '*': case '\'': case '(': case ')': case ';':
 620                case ':': case '@': case '&': case '=': case '+': case '$':
 621                case ',': case '/': case '?': case '#': case '[': case ']':
 622                        return 1;
 623        }
 624        return 0;
 625}
 626
 627static int is_rfc3986_unreserved(char ch)
 628{
 629        return isalnum(ch) ||
 630                ch == '-' || ch == '_' || ch == '.' || ch == '~';
 631}
 632
 633static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 634                                 int reserved)
 635{
 636        strbuf_grow(sb, len);
 637        while (len--) {
 638                char ch = *s++;
 639                if (is_rfc3986_unreserved(ch) ||
 640                    (!reserved && is_rfc3986_reserved(ch)))
 641                        strbuf_addch(sb, ch);
 642                else
 643                        strbuf_addf(sb, "%%%02x", ch);
 644        }
 645}
 646
 647void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 648                             int reserved)
 649{
 650        strbuf_add_urlencode(sb, s, strlen(s), reserved);
 651}
 652
 653void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 654{
 655        if (bytes > 1 << 30) {
 656                strbuf_addf(buf, "%u.%2.2u GiB",
 657                            (int)(bytes >> 30),
 658                            (int)(bytes & ((1 << 30) - 1)) / 10737419);
 659        } else if (bytes > 1 << 20) {
 660                int x = bytes + 5243;  /* for rounding */
 661                strbuf_addf(buf, "%u.%2.2u MiB",
 662                            x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 663        } else if (bytes > 1 << 10) {
 664                int x = bytes + 5;  /* for rounding */
 665                strbuf_addf(buf, "%u.%2.2u KiB",
 666                            x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 667        } else {
 668                strbuf_addf(buf, "%u bytes", (int)bytes);
 669        }
 670}
 671
 672void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 673{
 674        if (!*path)
 675                die("The empty string is not a valid path");
 676        if (!is_absolute_path(path)) {
 677                struct stat cwd_stat, pwd_stat;
 678                size_t orig_len = sb->len;
 679                char *cwd = xgetcwd();
 680                char *pwd = getenv("PWD");
 681                if (pwd && strcmp(pwd, cwd) &&
 682                    !stat(cwd, &cwd_stat) &&
 683                    (cwd_stat.st_dev || cwd_stat.st_ino) &&
 684                    !stat(pwd, &pwd_stat) &&
 685                    pwd_stat.st_dev == cwd_stat.st_dev &&
 686                    pwd_stat.st_ino == cwd_stat.st_ino)
 687                        strbuf_addstr(sb, pwd);
 688                else
 689                        strbuf_addstr(sb, cwd);
 690                if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 691                        strbuf_addch(sb, '/');
 692                free(cwd);
 693        }
 694        strbuf_addstr(sb, path);
 695}
 696
 697int printf_ln(const char *fmt, ...)
 698{
 699        int ret;
 700        va_list ap;
 701        va_start(ap, fmt);
 702        ret = vprintf(fmt, ap);
 703        va_end(ap);
 704        if (ret < 0 || putchar('\n') == EOF)
 705                return -1;
 706        return ret + 1;
 707}
 708
 709int fprintf_ln(FILE *fp, const char *fmt, ...)
 710{
 711        int ret;
 712        va_list ap;
 713        va_start(ap, fmt);
 714        ret = vfprintf(fp, fmt, ap);
 715        va_end(ap);
 716        if (ret < 0 || putc('\n', fp) == EOF)
 717                return -1;
 718        return ret + 1;
 719}
 720
 721char *xstrdup_tolower(const char *string)
 722{
 723        char *result;
 724        size_t len, i;
 725
 726        len = strlen(string);
 727        result = xmallocz(len);
 728        for (i = 0; i < len; i++)
 729                result[i] = tolower(string[i]);
 730        result[i] = '\0';
 731        return result;
 732}
 733
 734char *xstrvfmt(const char *fmt, va_list ap)
 735{
 736        struct strbuf buf = STRBUF_INIT;
 737        strbuf_vaddf(&buf, fmt, ap);
 738        return strbuf_detach(&buf, NULL);
 739}
 740
 741char *xstrfmt(const char *fmt, ...)
 742{
 743        va_list ap;
 744        char *ret;
 745
 746        va_start(ap, fmt);
 747        ret = xstrvfmt(fmt, ap);
 748        va_end(ap);
 749
 750        return ret;
 751}
 752
 753void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm)
 754{
 755        size_t hint = 128;
 756        size_t len;
 757
 758        if (!*fmt)
 759                return;
 760
 761        strbuf_grow(sb, hint);
 762        len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
 763
 764        if (!len) {
 765                /*
 766                 * strftime reports "0" if it could not fit the result in the buffer.
 767                 * Unfortunately, it also reports "0" if the requested time string
 768                 * takes 0 bytes. So our strategy is to munge the format so that the
 769                 * output contains at least one character, and then drop the extra
 770                 * character before returning.
 771                 */
 772                struct strbuf munged_fmt = STRBUF_INIT;
 773                strbuf_addf(&munged_fmt, "%s ", fmt);
 774                while (!len) {
 775                        hint *= 2;
 776                        strbuf_grow(sb, hint);
 777                        len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
 778                                       munged_fmt.buf, tm);
 779                }
 780                strbuf_release(&munged_fmt);
 781                len--; /* drop munged space */
 782        }
 783        strbuf_setlen(sb, sb->len + len);
 784}
 785
 786void strbuf_add_unique_abbrev(struct strbuf *sb, const unsigned char *sha1,
 787                              int abbrev_len)
 788{
 789        int r;
 790        strbuf_grow(sb, GIT_SHA1_HEXSZ + 1);
 791        r = find_unique_abbrev_r(sb->buf + sb->len, sha1, abbrev_len);
 792        strbuf_setlen(sb, sb->len + r);
 793}
 794
 795/*
 796 * Returns the length of a line, without trailing spaces.
 797 *
 798 * If the line ends with newline, it will be removed too.
 799 */
 800static size_t cleanup(char *line, size_t len)
 801{
 802        while (len) {
 803                unsigned char c = line[len - 1];
 804                if (!isspace(c))
 805                        break;
 806                len--;
 807        }
 808
 809        return len;
 810}
 811
 812/*
 813 * Remove empty lines from the beginning and end
 814 * and also trailing spaces from every line.
 815 *
 816 * Turn multiple consecutive empty lines between paragraphs
 817 * into just one empty line.
 818 *
 819 * If the input has only empty lines and spaces,
 820 * no output will be produced.
 821 *
 822 * If last line does not have a newline at the end, one is added.
 823 *
 824 * Enable skip_comments to skip every line starting with comment
 825 * character.
 826 */
 827void strbuf_stripspace(struct strbuf *sb, int skip_comments)
 828{
 829        int empties = 0;
 830        size_t i, j, len, newlen;
 831        char *eol;
 832
 833        /* We may have to add a newline. */
 834        strbuf_grow(sb, 1);
 835
 836        for (i = j = 0; i < sb->len; i += len, j += newlen) {
 837                eol = memchr(sb->buf + i, '\n', sb->len - i);
 838                len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
 839
 840                if (skip_comments && len && sb->buf[i] == comment_line_char) {
 841                        newlen = 0;
 842                        continue;
 843                }
 844                newlen = cleanup(sb->buf + i, len);
 845
 846                /* Not just an empty line? */
 847                if (newlen) {
 848                        if (empties > 0 && j > 0)
 849                                sb->buf[j++] = '\n';
 850                        empties = 0;
 851                        memmove(sb->buf + j, sb->buf + i, newlen);
 852                        sb->buf[newlen + j++] = '\n';
 853                } else {
 854                        empties++;
 855                }
 856        }
 857
 858        strbuf_setlen(sb, j);
 859}