strbuf.con commit Merge branch 'rk/commit-tree-make-F-verbatim' into maint (aec2eb8)
   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_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
 446                /*
 447                 * If getcwd(3) is implemented as a syscall that falls
 448                 * back to a regular lookup using readdir(3) etc. then
 449                 * we may be able to avoid EACCES by providing enough
 450                 * space to the syscall as it's not necessarily bound
 451                 * to the same restrictions as the fallback.
 452                 */
 453                if (errno == EACCES && guessed_len < PATH_MAX)
 454                        continue;
 455
 456                if (errno != ERANGE)
 457                        break;
 458        }
 459        if (oldalloc == 0)
 460                strbuf_release(sb);
 461        else
 462                strbuf_reset(sb);
 463        return -1;
 464}
 465
 466#ifdef HAVE_GETDELIM
 467int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 468{
 469        ssize_t r;
 470
 471        if (feof(fp))
 472                return EOF;
 473
 474        strbuf_reset(sb);
 475
 476        /* Translate slopbuf to NULL, as we cannot call realloc on it */
 477        if (!sb->alloc)
 478                sb->buf = NULL;
 479        errno = 0;
 480        r = getdelim(&sb->buf, &sb->alloc, term, fp);
 481
 482        if (r > 0) {
 483                sb->len = r;
 484                return 0;
 485        }
 486        assert(r == -1);
 487
 488        /*
 489         * Normally we would have called xrealloc, which will try to free
 490         * memory and recover. But we have no way to tell getdelim() to do so.
 491         * Worse, we cannot try to recover ENOMEM ourselves, because we have
 492         * no idea how many bytes were read by getdelim.
 493         *
 494         * Dying here is reasonable. It mirrors what xrealloc would do on
 495         * catastrophic memory failure. We skip the opportunity to free pack
 496         * memory and retry, but that's unlikely to help for a malloc small
 497         * enough to hold a single line of input, anyway.
 498         */
 499        if (errno == ENOMEM)
 500                die("Out of memory, getdelim failed");
 501
 502        /*
 503         * Restore strbuf invariants; if getdelim left us with a NULL pointer,
 504         * we can just re-init, but otherwise we should make sure that our
 505         * length is empty, and that the result is NUL-terminated.
 506         */
 507        if (!sb->buf)
 508                strbuf_init(sb, 0);
 509        else
 510                strbuf_reset(sb);
 511        return EOF;
 512}
 513#else
 514int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 515{
 516        int ch;
 517
 518        if (feof(fp))
 519                return EOF;
 520
 521        strbuf_reset(sb);
 522        flockfile(fp);
 523        while ((ch = getc_unlocked(fp)) != EOF) {
 524                if (!strbuf_avail(sb))
 525                        strbuf_grow(sb, 1);
 526                sb->buf[sb->len++] = ch;
 527                if (ch == term)
 528                        break;
 529        }
 530        funlockfile(fp);
 531        if (ch == EOF && sb->len == 0)
 532                return EOF;
 533
 534        sb->buf[sb->len] = '\0';
 535        return 0;
 536}
 537#endif
 538
 539static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
 540{
 541        if (strbuf_getwholeline(sb, fp, term))
 542                return EOF;
 543        if (sb->buf[sb->len - 1] == term)
 544                strbuf_setlen(sb, sb->len - 1);
 545        return 0;
 546}
 547
 548int strbuf_getline(struct strbuf *sb, FILE *fp)
 549{
 550        if (strbuf_getwholeline(sb, fp, '\n'))
 551                return EOF;
 552        if (sb->buf[sb->len - 1] == '\n') {
 553                strbuf_setlen(sb, sb->len - 1);
 554                if (sb->len && sb->buf[sb->len - 1] == '\r')
 555                        strbuf_setlen(sb, sb->len - 1);
 556        }
 557        return 0;
 558}
 559
 560int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
 561{
 562        return strbuf_getdelim(sb, fp, '\n');
 563}
 564
 565int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
 566{
 567        return strbuf_getdelim(sb, fp, '\0');
 568}
 569
 570int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 571{
 572        strbuf_reset(sb);
 573
 574        while (1) {
 575                char ch;
 576                ssize_t len = xread(fd, &ch, 1);
 577                if (len <= 0)
 578                        return EOF;
 579                strbuf_addch(sb, ch);
 580                if (ch == term)
 581                        break;
 582        }
 583        return 0;
 584}
 585
 586ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 587{
 588        int fd;
 589        ssize_t len;
 590
 591        fd = open(path, O_RDONLY);
 592        if (fd < 0)
 593                return -1;
 594        len = strbuf_read(sb, fd, hint);
 595        close(fd);
 596        if (len < 0)
 597                return -1;
 598
 599        return len;
 600}
 601
 602void strbuf_add_lines(struct strbuf *out, const char *prefix,
 603                      const char *buf, size_t size)
 604{
 605        add_lines(out, prefix, NULL, buf, size);
 606}
 607
 608void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 609{
 610        while (*s) {
 611                size_t len = strcspn(s, "\"<>&");
 612                strbuf_add(buf, s, len);
 613                s += len;
 614                switch (*s) {
 615                case '"':
 616                        strbuf_addstr(buf, "&quot;");
 617                        break;
 618                case '<':
 619                        strbuf_addstr(buf, "&lt;");
 620                        break;
 621                case '>':
 622                        strbuf_addstr(buf, "&gt;");
 623                        break;
 624                case '&':
 625                        strbuf_addstr(buf, "&amp;");
 626                        break;
 627                case 0:
 628                        return;
 629                }
 630                s++;
 631        }
 632}
 633
 634static int is_rfc3986_reserved(char ch)
 635{
 636        switch (ch) {
 637                case '!': case '*': case '\'': case '(': case ')': case ';':
 638                case ':': case '@': case '&': case '=': case '+': case '$':
 639                case ',': case '/': case '?': case '#': case '[': case ']':
 640                        return 1;
 641        }
 642        return 0;
 643}
 644
 645static int is_rfc3986_unreserved(char ch)
 646{
 647        return isalnum(ch) ||
 648                ch == '-' || ch == '_' || ch == '.' || ch == '~';
 649}
 650
 651static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 652                                 int reserved)
 653{
 654        strbuf_grow(sb, len);
 655        while (len--) {
 656                char ch = *s++;
 657                if (is_rfc3986_unreserved(ch) ||
 658                    (!reserved && is_rfc3986_reserved(ch)))
 659                        strbuf_addch(sb, ch);
 660                else
 661                        strbuf_addf(sb, "%%%02x", ch);
 662        }
 663}
 664
 665void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 666                             int reserved)
 667{
 668        strbuf_add_urlencode(sb, s, strlen(s), reserved);
 669}
 670
 671void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 672{
 673        if (bytes > 1 << 30) {
 674                strbuf_addf(buf, "%u.%2.2u GiB",
 675                            (int)(bytes >> 30),
 676                            (int)(bytes & ((1 << 30) - 1)) / 10737419);
 677        } else if (bytes > 1 << 20) {
 678                int x = bytes + 5243;  /* for rounding */
 679                strbuf_addf(buf, "%u.%2.2u MiB",
 680                            x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 681        } else if (bytes > 1 << 10) {
 682                int x = bytes + 5;  /* for rounding */
 683                strbuf_addf(buf, "%u.%2.2u KiB",
 684                            x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 685        } else {
 686                strbuf_addf(buf, "%u bytes", (int)bytes);
 687        }
 688}
 689
 690void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 691{
 692        if (!*path)
 693                die("The empty string is not a valid path");
 694        if (!is_absolute_path(path)) {
 695                struct stat cwd_stat, pwd_stat;
 696                size_t orig_len = sb->len;
 697                char *cwd = xgetcwd();
 698                char *pwd = getenv("PWD");
 699                if (pwd && strcmp(pwd, cwd) &&
 700                    !stat(cwd, &cwd_stat) &&
 701                    (cwd_stat.st_dev || cwd_stat.st_ino) &&
 702                    !stat(pwd, &pwd_stat) &&
 703                    pwd_stat.st_dev == cwd_stat.st_dev &&
 704                    pwd_stat.st_ino == cwd_stat.st_ino)
 705                        strbuf_addstr(sb, pwd);
 706                else
 707                        strbuf_addstr(sb, cwd);
 708                if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 709                        strbuf_addch(sb, '/');
 710                free(cwd);
 711        }
 712        strbuf_addstr(sb, path);
 713}
 714
 715void strbuf_add_real_path(struct strbuf *sb, const char *path)
 716{
 717        if (sb->len) {
 718                struct strbuf resolved = STRBUF_INIT;
 719                strbuf_realpath(&resolved, path, 1);
 720                strbuf_addbuf(sb, &resolved);
 721                strbuf_release(&resolved);
 722        } else
 723                strbuf_realpath(sb, path, 1);
 724}
 725
 726int printf_ln(const char *fmt, ...)
 727{
 728        int ret;
 729        va_list ap;
 730        va_start(ap, fmt);
 731        ret = vprintf(fmt, ap);
 732        va_end(ap);
 733        if (ret < 0 || putchar('\n') == EOF)
 734                return -1;
 735        return ret + 1;
 736}
 737
 738int fprintf_ln(FILE *fp, const char *fmt, ...)
 739{
 740        int ret;
 741        va_list ap;
 742        va_start(ap, fmt);
 743        ret = vfprintf(fp, fmt, ap);
 744        va_end(ap);
 745        if (ret < 0 || putc('\n', fp) == EOF)
 746                return -1;
 747        return ret + 1;
 748}
 749
 750char *xstrdup_tolower(const char *string)
 751{
 752        char *result;
 753        size_t len, i;
 754
 755        len = strlen(string);
 756        result = xmallocz(len);
 757        for (i = 0; i < len; i++)
 758                result[i] = tolower(string[i]);
 759        result[i] = '\0';
 760        return result;
 761}
 762
 763char *xstrvfmt(const char *fmt, va_list ap)
 764{
 765        struct strbuf buf = STRBUF_INIT;
 766        strbuf_vaddf(&buf, fmt, ap);
 767        return strbuf_detach(&buf, NULL);
 768}
 769
 770char *xstrfmt(const char *fmt, ...)
 771{
 772        va_list ap;
 773        char *ret;
 774
 775        va_start(ap, fmt);
 776        ret = xstrvfmt(fmt, ap);
 777        va_end(ap);
 778
 779        return ret;
 780}
 781
 782void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 783                     int tz_offset, int suppress_tz_name)
 784{
 785        struct strbuf munged_fmt = STRBUF_INIT;
 786        size_t hint = 128;
 787        size_t len;
 788
 789        if (!*fmt)
 790                return;
 791
 792        /*
 793         * There is no portable way to pass timezone information to
 794         * strftime, so we handle %z and %Z here.
 795         */
 796        for (;;) {
 797                const char *percent = strchrnul(fmt, '%');
 798                strbuf_add(&munged_fmt, fmt, percent - fmt);
 799                if (!*percent)
 800                        break;
 801                fmt = percent + 1;
 802                switch (*fmt) {
 803                case '%':
 804                        strbuf_addstr(&munged_fmt, "%%");
 805                        fmt++;
 806                        break;
 807                case 'z':
 808                        strbuf_addf(&munged_fmt, "%+05d", tz_offset);
 809                        fmt++;
 810                        break;
 811                case 'Z':
 812                        if (suppress_tz_name) {
 813                                fmt++;
 814                                break;
 815                        }
 816                        /* FALLTHROUGH */
 817                default:
 818                        strbuf_addch(&munged_fmt, '%');
 819                }
 820        }
 821        fmt = munged_fmt.buf;
 822
 823        strbuf_grow(sb, hint);
 824        len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
 825
 826        if (!len) {
 827                /*
 828                 * strftime reports "0" if it could not fit the result in the buffer.
 829                 * Unfortunately, it also reports "0" if the requested time string
 830                 * takes 0 bytes. So our strategy is to munge the format so that the
 831                 * output contains at least one character, and then drop the extra
 832                 * character before returning.
 833                 */
 834                strbuf_addch(&munged_fmt, ' ');
 835                while (!len) {
 836                        hint *= 2;
 837                        strbuf_grow(sb, hint);
 838                        len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
 839                                       munged_fmt.buf, tm);
 840                }
 841                len--; /* drop munged space */
 842        }
 843        strbuf_release(&munged_fmt);
 844        strbuf_setlen(sb, sb->len + len);
 845}
 846
 847void strbuf_add_unique_abbrev(struct strbuf *sb, const unsigned char *sha1,
 848                              int abbrev_len)
 849{
 850        int r;
 851        strbuf_grow(sb, GIT_SHA1_HEXSZ + 1);
 852        r = find_unique_abbrev_r(sb->buf + sb->len, sha1, abbrev_len);
 853        strbuf_setlen(sb, sb->len + r);
 854}
 855
 856/*
 857 * Returns the length of a line, without trailing spaces.
 858 *
 859 * If the line ends with newline, it will be removed too.
 860 */
 861static size_t cleanup(char *line, size_t len)
 862{
 863        while (len) {
 864                unsigned char c = line[len - 1];
 865                if (!isspace(c))
 866                        break;
 867                len--;
 868        }
 869
 870        return len;
 871}
 872
 873/*
 874 * Remove empty lines from the beginning and end
 875 * and also trailing spaces from every line.
 876 *
 877 * Turn multiple consecutive empty lines between paragraphs
 878 * into just one empty line.
 879 *
 880 * If the input has only empty lines and spaces,
 881 * no output will be produced.
 882 *
 883 * If last line does not have a newline at the end, one is added.
 884 *
 885 * Enable skip_comments to skip every line starting with comment
 886 * character.
 887 */
 888void strbuf_stripspace(struct strbuf *sb, int skip_comments)
 889{
 890        int empties = 0;
 891        size_t i, j, len, newlen;
 892        char *eol;
 893
 894        /* We may have to add a newline. */
 895        strbuf_grow(sb, 1);
 896
 897        for (i = j = 0; i < sb->len; i += len, j += newlen) {
 898                eol = memchr(sb->buf + i, '\n', sb->len - i);
 899                len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
 900
 901                if (skip_comments && len && sb->buf[i] == comment_line_char) {
 902                        newlen = 0;
 903                        continue;
 904                }
 905                newlen = cleanup(sb->buf + i, len);
 906
 907                /* Not just an empty line? */
 908                if (newlen) {
 909                        if (empties > 0 && j > 0)
 910                                sb->buf[j++] = '\n';
 911                        empties = 0;
 912                        memmove(sb->buf + j, sb->buf + i, newlen);
 913                        sb->buf[newlen + j++] = '\n';
 914                } else {
 915                        empties++;
 916                }
 917        }
 918
 919        strbuf_setlen(sb, j);
 920}
 921
 922int strbuf_normalize_path(struct strbuf *src)
 923{
 924        struct strbuf dst = STRBUF_INIT;
 925
 926        strbuf_grow(&dst, src->len);
 927        if (normalize_path_copy(dst.buf, src->buf) < 0) {
 928                strbuf_release(&dst);
 929                return -1;
 930        }
 931
 932        /*
 933         * normalize_path does not tell us the new length, so we have to
 934         * compute it by looking for the new NUL it placed
 935         */
 936        strbuf_setlen(&dst, strlen(dst.buf));
 937        strbuf_swap(src, &dst);
 938        strbuf_release(&dst);
 939        return 0;
 940}