Andrew's git / gitweb.git / strbuf.c
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strbuf.con commit Merge branch 'da/mergetool-meld' (48f662d)
   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') ? prefix2 : prefix1;
 233                strbuf_addstr(out, prefix);
 234                strbuf_add(out, buf, next - buf);
 235                size -= next - buf;
 236                buf = next;
 237        }
 238        strbuf_complete_line(out);
 239}
 240
 241void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 242{
 243        static char prefix1[3];
 244        static char prefix2[2];
 245
 246        if (prefix1[0] != comment_line_char) {
 247                sprintf(prefix1, "%c ", comment_line_char);
 248                sprintf(prefix2, "%c", comment_line_char);
 249        }
 250        add_lines(out, prefix1, prefix2, buf, size);
 251}
 252
 253void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 254{
 255        va_list params;
 256        struct strbuf buf = STRBUF_INIT;
 257        int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 258
 259        va_start(params, fmt);
 260        strbuf_vaddf(&buf, fmt, params);
 261        va_end(params);
 262
 263        strbuf_add_commented_lines(sb, buf.buf, buf.len);
 264        if (incomplete_line)
 265                sb->buf[--sb->len] = '\0';
 266
 267        strbuf_release(&buf);
 268}
 269
 270void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 271{
 272        int len;
 273        va_list cp;
 274
 275        if (!strbuf_avail(sb))
 276                strbuf_grow(sb, 64);
 277        va_copy(cp, ap);
 278        len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 279        va_end(cp);
 280        if (len < 0)
 281                die("BUG: your vsnprintf is broken (returned %d)", len);
 282        if (len > strbuf_avail(sb)) {
 283                strbuf_grow(sb, len);
 284                len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 285                if (len > strbuf_avail(sb))
 286                        die("BUG: your vsnprintf is broken (insatiable)");
 287        }
 288        strbuf_setlen(sb, sb->len + len);
 289}
 290
 291void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 292                   void *context)
 293{
 294        for (;;) {
 295                const char *percent;
 296                size_t consumed;
 297
 298                percent = strchrnul(format, '%');
 299                strbuf_add(sb, format, percent - format);
 300                if (!*percent)
 301                        break;
 302                format = percent + 1;
 303
 304                if (*format == '%') {
 305                        strbuf_addch(sb, '%');
 306                        format++;
 307                        continue;
 308                }
 309
 310                consumed = fn(sb, format, context);
 311                if (consumed)
 312                        format += consumed;
 313                else
 314                        strbuf_addch(sb, '%');
 315        }
 316}
 317
 318size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 319                void *context)
 320{
 321        struct strbuf_expand_dict_entry *e = context;
 322        size_t len;
 323
 324        for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 325                if (!strncmp(placeholder, e->placeholder, len)) {
 326                        if (e->value)
 327                                strbuf_addstr(sb, e->value);
 328                        return len;
 329                }
 330        }
 331        return 0;
 332}
 333
 334void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 335{
 336        int i, len = src->len;
 337
 338        for (i = 0; i < len; i++) {
 339                if (src->buf[i] == '%')
 340                        strbuf_addch(dst, '%');
 341                strbuf_addch(dst, src->buf[i]);
 342        }
 343}
 344
 345size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 346{
 347        size_t res;
 348        size_t oldalloc = sb->alloc;
 349
 350        strbuf_grow(sb, size);
 351        res = fread(sb->buf + sb->len, 1, size, f);
 352        if (res > 0)
 353                strbuf_setlen(sb, sb->len + res);
 354        else if (oldalloc == 0)
 355                strbuf_release(sb);
 356        return res;
 357}
 358
 359ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 360{
 361        size_t oldlen = sb->len;
 362        size_t oldalloc = sb->alloc;
 363
 364        strbuf_grow(sb, hint ? hint : 8192);
 365        for (;;) {
 366                ssize_t cnt;
 367
 368                cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 369                if (cnt < 0) {
 370                        if (oldalloc == 0)
 371                                strbuf_release(sb);
 372                        else
 373                                strbuf_setlen(sb, oldlen);
 374                        return -1;
 375                }
 376                if (!cnt)
 377                        break;
 378                sb->len += cnt;
 379                strbuf_grow(sb, 8192);
 380        }
 381
 382        sb->buf[sb->len] = '\0';
 383        return sb->len - oldlen;
 384}
 385
 386#define STRBUF_MAXLINK (2*PATH_MAX)
 387
 388int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 389{
 390        size_t oldalloc = sb->alloc;
 391
 392        if (hint < 32)
 393                hint = 32;
 394
 395        while (hint < STRBUF_MAXLINK) {
 396                int len;
 397
 398                strbuf_grow(sb, hint);
 399                len = readlink(path, sb->buf, hint);
 400                if (len < 0) {
 401                        if (errno != ERANGE)
 402                                break;
 403                } else if (len < hint) {
 404                        strbuf_setlen(sb, len);
 405                        return 0;
 406                }
 407
 408                /* .. the buffer was too small - try again */
 409                hint *= 2;
 410        }
 411        if (oldalloc == 0)
 412                strbuf_release(sb);
 413        return -1;
 414}
 415
 416int strbuf_getcwd(struct strbuf *sb)
 417{
 418        size_t oldalloc = sb->alloc;
 419        size_t guessed_len = 128;
 420
 421        for (;; guessed_len *= 2) {
 422                strbuf_grow(sb, guessed_len);
 423                if (getcwd(sb->buf, sb->alloc)) {
 424                        strbuf_setlen(sb, strlen(sb->buf));
 425                        return 0;
 426                }
 427                if (errno != ERANGE)
 428                        break;
 429        }
 430        if (oldalloc == 0)
 431                strbuf_release(sb);
 432        else
 433                strbuf_reset(sb);
 434        return -1;
 435}
 436
 437int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 438{
 439        int ch;
 440
 441        if (feof(fp))
 442                return EOF;
 443
 444        strbuf_reset(sb);
 445        while ((ch = fgetc(fp)) != EOF) {
 446                strbuf_grow(sb, 1);
 447                sb->buf[sb->len++] = ch;
 448                if (ch == term)
 449                        break;
 450        }
 451        if (ch == EOF && sb->len == 0)
 452                return EOF;
 453
 454        sb->buf[sb->len] = '\0';
 455        return 0;
 456}
 457
 458int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 459{
 460        if (strbuf_getwholeline(sb, fp, term))
 461                return EOF;
 462        if (sb->buf[sb->len-1] == term)
 463                strbuf_setlen(sb, sb->len-1);
 464        return 0;
 465}
 466
 467int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 468{
 469        strbuf_reset(sb);
 470
 471        while (1) {
 472                char ch;
 473                ssize_t len = xread(fd, &ch, 1);
 474                if (len <= 0)
 475                        return EOF;
 476                strbuf_addch(sb, ch);
 477                if (ch == term)
 478                        break;
 479        }
 480        return 0;
 481}
 482
 483int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 484{
 485        int fd, len;
 486
 487        fd = open(path, O_RDONLY);
 488        if (fd < 0)
 489                return -1;
 490        len = strbuf_read(sb, fd, hint);
 491        close(fd);
 492        if (len < 0)
 493                return -1;
 494
 495        return len;
 496}
 497
 498void strbuf_add_lines(struct strbuf *out, const char *prefix,
 499                      const char *buf, size_t size)
 500{
 501        add_lines(out, prefix, NULL, buf, size);
 502}
 503
 504void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 505{
 506        while (*s) {
 507                size_t len = strcspn(s, "\"<>&");
 508                strbuf_add(buf, s, len);
 509                s += len;
 510                switch (*s) {
 511                case '"':
 512                        strbuf_addstr(buf, "&quot;");
 513                        break;
 514                case '<':
 515                        strbuf_addstr(buf, "&lt;");
 516                        break;
 517                case '>':
 518                        strbuf_addstr(buf, "&gt;");
 519                        break;
 520                case '&':
 521                        strbuf_addstr(buf, "&amp;");
 522                        break;
 523                case 0:
 524                        return;
 525                }
 526                s++;
 527        }
 528}
 529
 530static int is_rfc3986_reserved(char ch)
 531{
 532        switch (ch) {
 533                case '!': case '*': case '\'': case '(': case ')': case ';':
 534                case ':': case '@': case '&': case '=': case '+': case '$':
 535                case ',': case '/': case '?': case '#': case '[': case ']':
 536                        return 1;
 537        }
 538        return 0;
 539}
 540
 541static int is_rfc3986_unreserved(char ch)
 542{
 543        return isalnum(ch) ||
 544                ch == '-' || ch == '_' || ch == '.' || ch == '~';
 545}
 546
 547static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 548                                 int reserved)
 549{
 550        strbuf_grow(sb, len);
 551        while (len--) {
 552                char ch = *s++;
 553                if (is_rfc3986_unreserved(ch) ||
 554                    (!reserved && is_rfc3986_reserved(ch)))
 555                        strbuf_addch(sb, ch);
 556                else
 557                        strbuf_addf(sb, "%%%02x", ch);
 558        }
 559}
 560
 561void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 562                             int reserved)
 563{
 564        strbuf_add_urlencode(sb, s, strlen(s), reserved);
 565}
 566
 567void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 568{
 569        if (bytes > 1 << 30) {
 570                strbuf_addf(buf, "%u.%2.2u GiB",
 571                            (int)(bytes >> 30),
 572                            (int)(bytes & ((1 << 30) - 1)) / 10737419);
 573        } else if (bytes > 1 << 20) {
 574                int x = bytes + 5243;  /* for rounding */
 575                strbuf_addf(buf, "%u.%2.2u MiB",
 576                            x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 577        } else if (bytes > 1 << 10) {
 578                int x = bytes + 5;  /* for rounding */
 579                strbuf_addf(buf, "%u.%2.2u KiB",
 580                            x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 581        } else {
 582                strbuf_addf(buf, "%u bytes", (int)bytes);
 583        }
 584}
 585
 586void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
 587{
 588        if (!*path)
 589                die("The empty string is not a valid path");
 590        if (!is_absolute_path(path)) {
 591                struct stat cwd_stat, pwd_stat;
 592                size_t orig_len = sb->len;
 593                char *cwd = xgetcwd();
 594                char *pwd = getenv("PWD");
 595                if (pwd && strcmp(pwd, cwd) &&
 596                    !stat(cwd, &cwd_stat) &&
 597                    (cwd_stat.st_dev || cwd_stat.st_ino) &&
 598                    !stat(pwd, &pwd_stat) &&
 599                    pwd_stat.st_dev == cwd_stat.st_dev &&
 600                    pwd_stat.st_ino == cwd_stat.st_ino)
 601                        strbuf_addstr(sb, pwd);
 602                else
 603                        strbuf_addstr(sb, cwd);
 604                if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
 605                        strbuf_addch(sb, '/');
 606                free(cwd);
 607        }
 608        strbuf_addstr(sb, path);
 609}
 610
 611int printf_ln(const char *fmt, ...)
 612{
 613        int ret;
 614        va_list ap;
 615        va_start(ap, fmt);
 616        ret = vprintf(fmt, ap);
 617        va_end(ap);
 618        if (ret < 0 || putchar('\n') == EOF)
 619                return -1;
 620        return ret + 1;
 621}
 622
 623int fprintf_ln(FILE *fp, const char *fmt, ...)
 624{
 625        int ret;
 626        va_list ap;
 627        va_start(ap, fmt);
 628        ret = vfprintf(fp, fmt, ap);
 629        va_end(ap);
 630        if (ret < 0 || putc('\n', fp) == EOF)
 631                return -1;
 632        return ret + 1;
 633}
 634
 635char *xstrdup_tolower(const char *string)
 636{
 637        char *result;
 638        size_t len, i;
 639
 640        len = strlen(string);
 641        result = xmalloc(len + 1);
 642        for (i = 0; i < len; i++)
 643                result[i] = tolower(string[i]);
 644        result[i] = '\0';
 645        return result;
 646}
 647
 648char *xstrvfmt(const char *fmt, va_list ap)
 649{
 650        struct strbuf buf = STRBUF_INIT;
 651        strbuf_vaddf(&buf, fmt, ap);
 652        return strbuf_detach(&buf, NULL);
 653}
 654
 655char *xstrfmt(const char *fmt, ...)
 656{
 657        va_list ap;
 658        char *ret;
 659
 660        va_start(ap, fmt);
 661        ret = xstrvfmt(fmt, ap);
 662        va_end(ap);
 663
 664        return ret;
 665}