strbuf.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "utf8.h"
   4
   5 int 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  */
  19 char strbuf_slopbuf[1];
  20
  21 void 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
  29 void strbuf_release(struct strbuf *sb)
  30 {
  31         if (sb->alloc) {
  32                 free(sb->buf);
  33                 strbuf_init(sb, 0);
  34         }
  35 }
  36
  37 char *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
  48 void 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
  58 void 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
  71 void strbuf_trim(struct strbuf *sb)
  72 {
  73         strbuf_rtrim(sb);
  74         strbuf_ltrim(sb);
  75 }
  76 void 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
  83 void 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
  94 int 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
 110 void 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
 117 struct 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
 144 void 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
 155 int 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
 164 void 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
 183 void 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
 188 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 189 {
 190         strbuf_splice(sb, pos, len, NULL, 0);
 191 }
 192
 193 void 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
 200 void 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
 207 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 208 {
 209         va_list ap;
 210         va_start(ap, fmt);
 211         strbuf_vaddf(sb, fmt, ap);
 212         va_end(ap);
 213 }
 214
 215 static void add_lines(struct strbuf *out,
 216                         const char *prefix1,
 217                         const char *prefix2,
 218                         const char *buf, size_t size)
 219 {
 220         while (size) {
 221                 const char *prefix;
 222                 const char *next = memchr(buf, '\n', size);
 223                 next = next ? (next + 1) : (buf + size);
 224
 225                 prefix = (prefix2 && buf[0] == '\n') ? prefix2 : prefix1;
 226                 strbuf_addstr(out, prefix);
 227                 strbuf_add(out, buf, next - buf);
 228                 size -= next - buf;
 229                 buf = next;
 230         }
 231         strbuf_complete_line(out);
 232 }
 233
 234 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 235 {
 236         static char prefix1[3];
 237         static char prefix2[2];
 238
 239         if (prefix1[0] != comment_line_char) {
 240                 sprintf(prefix1, "%c ", comment_line_char);
 241                 sprintf(prefix2, "%c", comment_line_char);
 242         }
 243         add_lines(out, prefix1, prefix2, buf, size);
 244 }
 245
 246 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 247 {
 248         va_list params;
 249         struct strbuf buf = STRBUF_INIT;
 250         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 251
 252         va_start(params, fmt);
 253         strbuf_vaddf(&buf, fmt, params);
 254         va_end(params);
 255
 256         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 257         if (incomplete_line)
 258                 sb->buf[--sb->len] = '\0';
 259
 260         strbuf_release(&buf);
 261 }
 262
 263 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 264 {
 265         int len;
 266         va_list cp;
 267
 268         if (!strbuf_avail(sb))
 269                 strbuf_grow(sb, 64);
 270         va_copy(cp, ap);
 271         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 272         va_end(cp);
 273         if (len < 0)
 274                 die("BUG: your vsnprintf is broken (returned %d)", len);
 275         if (len > strbuf_avail(sb)) {
 276                 strbuf_grow(sb, len);
 277                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 278                 if (len > strbuf_avail(sb))
 279                         die("BUG: your vsnprintf is broken (insatiable)");
 280         }
 281         strbuf_setlen(sb, sb->len + len);
 282 }
 283
 284 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 285                    void *context)
 286 {
 287         for (;;) {
 288                 const char *percent;
 289                 size_t consumed;
 290
 291                 percent = strchrnul(format, '%');
 292                 strbuf_add(sb, format, percent - format);
 293                 if (!*percent)
 294                         break;
 295                 format = percent + 1;
 296
 297                 if (*format == '%') {
 298                         strbuf_addch(sb, '%');
 299                         format++;
 300                         continue;
 301                 }
 302
 303                 consumed = fn(sb, format, context);
 304                 if (consumed)
 305                         format += consumed;
 306                 else
 307                         strbuf_addch(sb, '%');
 308         }
 309 }
 310
 311 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 312                 void *context)
 313 {
 314         struct strbuf_expand_dict_entry *e = context;
 315         size_t len;
 316
 317         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 318                 if (!strncmp(placeholder, e->placeholder, len)) {
 319                         if (e->value)
 320                                 strbuf_addstr(sb, e->value);
 321                         return len;
 322                 }
 323         }
 324         return 0;
 325 }
 326
 327 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 328 {
 329         int i, len = src->len;
 330
 331         for (i = 0; i < len; i++) {
 332                 if (src->buf[i] == '%')
 333                         strbuf_addch(dst, '%');
 334                 strbuf_addch(dst, src->buf[i]);
 335         }
 336 }
 337
 338 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 339 {
 340         size_t res;
 341         size_t oldalloc = sb->alloc;
 342
 343         strbuf_grow(sb, size);
 344         res = fread(sb->buf + sb->len, 1, size, f);
 345         if (res > 0)
 346                 strbuf_setlen(sb, sb->len + res);
 347         else if (oldalloc == 0)
 348                 strbuf_release(sb);
 349         return res;
 350 }
 351
 352 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 353 {
 354         size_t oldlen = sb->len;
 355         size_t oldalloc = sb->alloc;
 356
 357         strbuf_grow(sb, hint ? hint : 8192);
 358         for (;;) {
 359                 ssize_t cnt;
 360
 361                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 362                 if (cnt < 0) {
 363                         if (oldalloc == 0)
 364                                 strbuf_release(sb);
 365                         else
 366                                 strbuf_setlen(sb, oldlen);
 367                         return -1;
 368                 }
 369                 if (!cnt)
 370                         break;
 371                 sb->len += cnt;
 372                 strbuf_grow(sb, 8192);
 373         }
 374
 375         sb->buf[sb->len] = '\0';
 376         return sb->len - oldlen;
 377 }
 378
 379 #define STRBUF_MAXLINK (2*PATH_MAX)
 380
 381 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 382 {
 383         size_t oldalloc = sb->alloc;
 384
 385         if (hint < 32)
 386                 hint = 32;
 387
 388         while (hint < STRBUF_MAXLINK) {
 389                 int len;
 390
 391                 strbuf_grow(sb, hint);
 392                 len = readlink(path, sb->buf, hint);
 393                 if (len < 0) {
 394                         if (errno != ERANGE)
 395                                 break;
 396                 } else if (len < hint) {
 397                         strbuf_setlen(sb, len);
 398                         return 0;
 399                 }
 400
 401                 /* .. the buffer was too small - try again */
 402                 hint *= 2;
 403         }
 404         if (oldalloc == 0)
 405                 strbuf_release(sb);
 406         return -1;
 407 }
 408
 409 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 410 {
 411         int ch;
 412
 413         if (feof(fp))
 414                 return EOF;
 415
 416         strbuf_reset(sb);
 417         while ((ch = fgetc(fp)) != EOF) {
 418                 strbuf_grow(sb, 1);
 419                 sb->buf[sb->len++] = ch;
 420                 if (ch == term)
 421                         break;
 422         }
 423         if (ch == EOF && sb->len == 0)
 424                 return EOF;
 425
 426         sb->buf[sb->len] = '\0';
 427         return 0;
 428 }
 429
 430 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 431 {
 432         if (strbuf_getwholeline(sb, fp, term))
 433                 return EOF;
 434         if (sb->buf[sb->len-1] == term)
 435                 strbuf_setlen(sb, sb->len-1);
 436         return 0;
 437 }
 438
 439 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 440 {
 441         strbuf_reset(sb);
 442
 443         while (1) {
 444                 char ch;
 445                 ssize_t len = xread(fd, &ch, 1);
 446                 if (len <= 0)
 447                         return EOF;
 448                 strbuf_addch(sb, ch);
 449                 if (ch == term)
 450                         break;
 451         }
 452         return 0;
 453 }
 454
 455 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 456 {
 457         int fd, len;
 458
 459         fd = open(path, O_RDONLY);
 460         if (fd < 0)
 461                 return -1;
 462         len = strbuf_read(sb, fd, hint);
 463         close(fd);
 464         if (len < 0)
 465                 return -1;
 466
 467         return len;
 468 }
 469
 470 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 471                       const char *buf, size_t size)
 472 {
 473         add_lines(out, prefix, NULL, buf, size);
 474 }
 475
 476 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 477 {
 478         while (*s) {
 479                 size_t len = strcspn(s, "\"<>&");
 480                 strbuf_add(buf, s, len);
 481                 s += len;
 482                 switch (*s) {
 483                 case '"':
 484                         strbuf_addstr(buf, "&quot;");
 485                         break;
 486                 case '<':
 487                         strbuf_addstr(buf, "&lt;");
 488                         break;
 489                 case '>':
 490                         strbuf_addstr(buf, "&gt;");
 491                         break;
 492                 case '&':
 493                         strbuf_addstr(buf, "&amp;");
 494                         break;
 495                 case 0:
 496                         return;
 497                 }
 498                 s++;
 499         }
 500 }
 501
 502 static int is_rfc3986_reserved(char ch)
 503 {
 504         switch (ch) {
 505                 case '!': case '*': case '\'': case '(': case ')': case ';':
 506                 case ':': case '@': case '&': case '=': case '+': case '$':
 507                 case ',': case '/': case '?': case '#': case '[': case ']':
 508                         return 1;
 509         }
 510         return 0;
 511 }
 512
 513 static int is_rfc3986_unreserved(char ch)
 514 {
 515         return isalnum(ch) ||
 516                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 517 }
 518
 519 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 520                                  int reserved)
 521 {
 522         strbuf_grow(sb, len);
 523         while (len--) {
 524                 char ch = *s++;
 525                 if (is_rfc3986_unreserved(ch) ||
 526                     (!reserved && is_rfc3986_reserved(ch)))
 527                         strbuf_addch(sb, ch);
 528                 else
 529                         strbuf_addf(sb, "%%%02x", ch);
 530         }
 531 }
 532
 533 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 534                              int reserved)
 535 {
 536         strbuf_add_urlencode(sb, s, strlen(s), reserved);
 537 }
 538
 539 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 540 {
 541         if (bytes > 1 << 30) {
 542                 strbuf_addf(buf, "%u.%2.2u GiB",
 543                             (int)(bytes >> 30),
 544                             (int)(bytes & ((1 << 30) - 1)) / 10737419);
 545         } else if (bytes > 1 << 20) {
 546                 int x = bytes + 5243;  /* for rounding */
 547                 strbuf_addf(buf, "%u.%2.2u MiB",
 548                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 549         } else if (bytes > 1 << 10) {
 550                 int x = bytes + 5;  /* for rounding */
 551                 strbuf_addf(buf, "%u.%2.2u KiB",
 552                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 553         } else {
 554                 strbuf_addf(buf, "%u bytes", (int)bytes);
 555         }
 556 }
 557
 558 int printf_ln(const char *fmt, ...)
 559 {
 560         int ret;
 561         va_list ap;
 562         va_start(ap, fmt);
 563         ret = vprintf(fmt, ap);
 564         va_end(ap);
 565         if (ret < 0 || putchar('\n') == EOF)
 566                 return -1;
 567         return ret + 1;
 568 }
 569
 570 int fprintf_ln(FILE *fp, const char *fmt, ...)
 571 {
 572         int ret;
 573         va_list ap;
 574         va_start(ap, fmt);
 575         ret = vfprintf(fp, fmt, ap);
 576         va_end(ap);
 577         if (ret < 0 || putc('\n', fp) == EOF)
 578                 return -1;
 579         return ret + 1;
 580 }
 581
 582 char *xstrdup_tolower(const char *string)
 583 {
 584         char *result;
 585         size_t len, i;
 586
 587         len = strlen(string);
 588         result = xmalloc(len + 1);
 589         for (i = 0; i < len; i++)
 590                 result[i] = tolower(string[i]);
 591         result[i] = '\0';
 592         return result;
 593 }
 594
 595 char *xstrvfmt(const char *fmt, va_list ap)
 596 {
 597         struct strbuf buf = STRBUF_INIT;
 598         strbuf_vaddf(&buf, fmt, ap);
 599         return strbuf_detach(&buf, NULL);
 600 }
 601
 602 char *xstrfmt(const char *fmt, ...)
 603 {
 604         va_list ap;
 605         char *ret;
 606
 607         va_start(ap, fmt);
 608         ret = xstrvfmt(fmt, ap);
 609         va_end(ap);
 610
 611         return ret;
 612 }