Andrew's git / gitweb.git / strbuf.c
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strbuf.con commit Documentation/git-bisect.txt: git bisect term → git bisect terms (bbd374d)
   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                sprintf(prefix1, "%c ", comment_line_char);
 249                sprintf(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 cnt;
 368
 369                cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 370                if (cnt < 0) {
 371                        if (oldalloc == 0)
 372                                strbuf_release(sb);
 373                        else
 374                                strbuf_setlen(sb, oldlen);
 375                        return -1;
 376                }
 377                if (!cnt)
 378                        break;
 379                sb->len += cnt;
 380                strbuf_grow(sb, 8192);
 381        }
 382
 383        sb->buf[sb->len] = '\0';
 384        return sb->len - oldlen;
 385}
 386
 387#define STRBUF_MAXLINK (2*PATH_MAX)
 388
 389int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 390{
 391        size_t oldalloc = sb->alloc;
 392
 393        if (hint < 32)
 394                hint = 32;
 395
 396        while (hint < STRBUF_MAXLINK) {
 397                int len;
 398
 399                strbuf_grow(sb, hint);
 400                len = readlink(path, sb->buf, hint);
 401                if (len < 0) {
 402                        if (errno != ERANGE)
 403                                break;
 404                } else if (len < hint) {
 405                        strbuf_setlen(sb, len);
 406                        return 0;
 407                }
 408
 409                /* .. the buffer was too small - try again */
 410                hint *= 2;
 411        }
 412        if (oldalloc == 0)
 413                strbuf_release(sb);
 414        return -1;
 415}
 416
 417int strbuf_getcwd(struct strbuf *sb)
 418{
 419        size_t oldalloc = sb->alloc;
 420        size_t guessed_len = 128;
 421
 422        for (;; guessed_len *= 2) {
 423                strbuf_grow(sb, guessed_len);
 424                if (getcwd(sb->buf, sb->alloc)) {
 425                        strbuf_setlen(sb, strlen(sb->buf));
 426                        return 0;
 427                }
 428                if (errno != ERANGE)
 429                        break;
 430        }
 431        if (oldalloc == 0)
 432                strbuf_release(sb);
 433        else
 434                strbuf_reset(sb);
 435        return -1;
 436}
 437
 438#ifdef HAVE_GETDELIM
 439int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 440{
 441        ssize_t r;
 442
 443        if (feof(fp))
 444                return EOF;
 445
 446        strbuf_reset(sb);
 447
 448        /* Translate slopbuf to NULL, as we cannot call realloc on it */
 449        if (!sb->alloc)
 450                sb->buf = NULL;
 451        r = getdelim(&sb->buf, &sb->alloc, term, fp);
 452
 453        if (r > 0) {
 454                sb->len = r;
 455                return 0;
 456        }
 457        assert(r == -1);
 458
 459        /*
 460         * Normally we would have called xrealloc, which will try to free
 461         * memory and recover. But we have no way to tell getdelim() to do so.
 462         * Worse, we cannot try to recover ENOMEM ourselves, because we have
 463         * no idea how many bytes were read by getdelim.
 464         *
 465         * Dying here is reasonable. It mirrors what xrealloc would do on
 466         * catastrophic memory failure. We skip the opportunity to free pack
 467         * memory and retry, but that's unlikely to help for a malloc small
 468         * enough to hold a single line of input, anyway.
 469         */
 470        if (errno == ENOMEM)
 471                die("Out of memory, getdelim failed");
 472
 473        /* Restore slopbuf that we moved out of the way before */
 474        if (!sb->buf)
 475                strbuf_init(sb, 0);
 476        return EOF;
 477}
 478#else
 479int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 480{
 481        int ch;
 482
 483        if (feof(fp))
 484                return EOF;
 485
 486        strbuf_reset(sb);
 487        flockfile(fp);
 488        while ((ch = getc_unlocked(fp)) != EOF) {
 489                if (!strbuf_avail(sb))
 490                        strbuf_grow(sb, 1);
 491                sb->buf[sb->len++] = ch;
 492                if (ch == term)
 493                        break;
 494        }
 495        funlockfile(fp);
 496        if (ch == EOF && sb->len == 0)
 497                return EOF;
 498
 499        sb->buf[sb->len] = '\0';
 500        return 0;
 501}
 502#endif
 503
 504int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 505{
 506        if (strbuf_getwholeline(sb, fp, term))
 507                return EOF;
 508        if (sb->buf[sb->len-1] == term)
 509                strbuf_setlen(sb, sb->len-1);
 510        return 0;
 511}
 512
 513int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 514{
 515        strbuf_reset(sb);
 516
 517        while (1) {
 518                char ch;
 519                ssize_t len = xread(fd, &ch, 1);
 520                if (len <= 0)
 521                        return EOF;
 522                strbuf_addch(sb, ch);
 523                if (ch == term)
 524                        break;
 525        }
 526        return 0;
 527}
 528
 529int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 530{
 531        int fd, len;
 532
 533        fd = open(path, O_RDONLY);
 534        if (fd < 0)
 535                return -1;
 536        len = strbuf_read(sb, fd, hint);
 537        close(fd);
 538        if (len < 0)
 539                return -1;
 540
 541        return len;
 542}
 543
 544void strbuf_add_lines(struct strbuf *out, const char *prefix,
 545                      const char *buf, size_t size)
 546{
 547        add_lines(out, prefix, NULL, buf, size);
 548}
 549
 550void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 551{
 552        while (*s) {
 553                size_t len = strcspn(s, "\"<>&");
 554                strbuf_add(buf, s, len);
 555                s += len;
 556                switch (*s) {
 557                case '"':
 558                        strbuf_addstr(buf, "&quot;");
 559                        break;
 560                case '<':
 561                        strbuf_addstr(buf, "&lt;");
 562                        break;
 563                case '>':
 564                        strbuf_addstr(buf, "&gt;");
 565                        break;
 566                case '&':
 567                        strbuf_addstr(buf, "&amp;");
 568                        break;
 569                case 0:
 570                        return;
 571                }
 572                s++;
 573        }
 574}
 575
 576static int is_rfc3986_reserved(char ch)
 577{
 578        switch (ch) {
 579                case '!': case '*': case '\'': case '(': case ')': case ';':
 580                case ':': case '@': case '&': case '=': case '+': case '$':
 581                case ',': case '/': case '?': case '#': case '[': case ']':
 582                        return 1;
 583        }
 584        return 0;
 585}
 586
 587static int is_rfc3986_unreserved(char ch)
 588{
 589        return isalnum(ch) ||
 590                ch == '-' || ch == '_' || ch == '.' || ch == '~';
 591}
 592
 593static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 594                                 int reserved)
 595{
 596        strbuf_grow(sb, len);
 597        while (len--) {
 598                char ch = *s++;
 599                if (is_rfc3986_unreserved(ch) ||
 600                    (!reserved && is_rfc3986_reserved(ch)))
 601                        strbuf_addch(sb, ch);
 602                else
 603                        strbuf_addf(sb, "%%%02x", ch);
 604        }
 605}
 606
 607void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 608                             int reserved)
 609{
 610        strbuf_add_urlencode(sb, s, strlen(s), reserved);
 611}
 612
 613void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 614{
 615        if (bytes > 1 << 30) {
 616                strbuf_addf(buf, "%u.%2.2u GiB",
 617                            (int)(bytes >> 30),
 618                            (int)(bytes & ((1 << 30) - 1)) / 10737419);
 619        } else if (bytes > 1 << 20) {
 620                int x = bytes + 5243;  /* for rounding */
 621                strbuf_addf(buf, "%u.%2.2u MiB",
 622                            x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 623        } else if (bytes > 1 << 10) {
 624                int x = bytes + 5;  /* for rounding */
 625                strbuf_addf(buf, "%u.%2.2u KiB",
 626                            x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 627        } else {
 628                strbuf_addf(buf, "%u bytes", (int)bytes);
 629        }
 630}
 631
 632void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 633{
 634        if (!*path)
 635                die("The empty string is not a valid path");
 636        if (!is_absolute_path(path)) {
 637                struct stat cwd_stat, pwd_stat;
 638                size_t orig_len = sb->len;
 639                char *cwd = xgetcwd();
 640                char *pwd = getenv("PWD");
 641                if (pwd && strcmp(pwd, cwd) &&
 642                    !stat(cwd, &cwd_stat) &&
 643                    (cwd_stat.st_dev || cwd_stat.st_ino) &&
 644                    !stat(pwd, &pwd_stat) &&
 645                    pwd_stat.st_dev == cwd_stat.st_dev &&
 646                    pwd_stat.st_ino == cwd_stat.st_ino)
 647                        strbuf_addstr(sb, pwd);
 648                else
 649                        strbuf_addstr(sb, cwd);
 650                if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 651                        strbuf_addch(sb, '/');
 652                free(cwd);
 653        }
 654        strbuf_addstr(sb, path);
 655}
 656
 657int printf_ln(const char *fmt, ...)
 658{
 659        int ret;
 660        va_list ap;
 661        va_start(ap, fmt);
 662        ret = vprintf(fmt, ap);
 663        va_end(ap);
 664        if (ret < 0 || putchar('\n') == EOF)
 665                return -1;
 666        return ret + 1;
 667}
 668
 669int fprintf_ln(FILE *fp, const char *fmt, ...)
 670{
 671        int ret;
 672        va_list ap;
 673        va_start(ap, fmt);
 674        ret = vfprintf(fp, fmt, ap);
 675        va_end(ap);
 676        if (ret < 0 || putc('\n', fp) == EOF)
 677                return -1;
 678        return ret + 1;
 679}
 680
 681char *xstrdup_tolower(const char *string)
 682{
 683        char *result;
 684        size_t len, i;
 685
 686        len = strlen(string);
 687        result = xmalloc(len + 1);
 688        for (i = 0; i < len; i++)
 689                result[i] = tolower(string[i]);
 690        result[i] = '\0';
 691        return result;
 692}
 693
 694char *xstrvfmt(const char *fmt, va_list ap)
 695{
 696        struct strbuf buf = STRBUF_INIT;
 697        strbuf_vaddf(&buf, fmt, ap);
 698        return strbuf_detach(&buf, NULL);
 699}
 700
 701char *xstrfmt(const char *fmt, ...)
 702{
 703        va_list ap;
 704        char *ret;
 705
 706        va_start(ap, fmt);
 707        ret = xstrvfmt(fmt, ap);
 708        va_end(ap);
 709
 710        return ret;
 711}