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 int ends_with(const char *str, const char *suffix)
  15 {
  16         int len = strlen(str), suflen = strlen(suffix);
  17         if (len < suflen)
  18                 return 0;
  19         else
  20                 return !strcmp(str + len - suflen, suffix);
  21 }
  22
  23 /*
  24  * Used as the default ->buf value, so that people can always assume
  25  * buf is non NULL and ->buf is NUL terminated even for a freshly
  26  * initialized strbuf.
  27  */
  28 char strbuf_slopbuf[1];
  29
  30 void strbuf_init(struct strbuf *sb, size_t hint)
  31 {
  32         sb->alloc = sb->len = 0;
  33         sb->buf = strbuf_slopbuf;
  34         if (hint)
  35                 strbuf_grow(sb, hint);
  36 }
  37
  38 void strbuf_release(struct strbuf *sb)
  39 {
  40         if (sb->alloc) {
  41                 free(sb->buf);
  42                 strbuf_init(sb, 0);
  43         }
  44 }
  45
  46 char *strbuf_detach(struct strbuf *sb, size_t *sz)
  47 {
  48         char *res;
  49         strbuf_grow(sb, 0);
  50         res = sb->buf;
  51         if (sz)
  52                 *sz = sb->len;
  53         strbuf_init(sb, 0);
  54         return res;
  55 }
  56
  57 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  58 {
  59         strbuf_release(sb);
  60         sb->buf   = buf;
  61         sb->len   = len;
  62         sb->alloc = alloc;
  63         strbuf_grow(sb, 0);
  64         sb->buf[sb->len] = '\0';
  65 }
  66
  67 void strbuf_grow(struct strbuf *sb, size_t extra)
  68 {
  69         int new_buf = !sb->alloc;
  70         if (unsigned_add_overflows(extra, 1) ||
  71             unsigned_add_overflows(sb->len, extra + 1))
  72                 die("you want to use way too much memory");
  73         if (new_buf)
  74                 sb->buf = NULL;
  75         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  76         if (new_buf)
  77                 sb->buf[0] = '\0';
  78 }
  79
  80 void strbuf_trim(struct strbuf *sb)
  81 {
  82         strbuf_rtrim(sb);
  83         strbuf_ltrim(sb);
  84 }
  85 void strbuf_rtrim(struct strbuf *sb)
  86 {
  87         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  88                 sb->len--;
  89         sb->buf[sb->len] = '\0';
  90 }
  91
  92 void strbuf_ltrim(struct strbuf *sb)
  93 {
  94         char *b = sb->buf;
  95         while (sb->len > 0 && isspace(*b)) {
  96                 b++;
  97                 sb->len--;
  98         }
  99         memmove(sb->buf, b, sb->len);
 100         sb->buf[sb->len] = '\0';
 101 }
 102
 103 int strbuf_reencode(struct strbuf *sb, const char *from, const char *to)
 104 {
 105         char *out;
 106         int len;
 107
 108         if (same_encoding(from, to))
 109                 return 0;
 110
 111         out = reencode_string_len(sb->buf, sb->len, to, from, &len);
 112         if (!out)
 113                 return -1;
 114
 115         strbuf_attach(sb, out, len, len);
 116         return 0;
 117 }
 118
 119 void strbuf_tolower(struct strbuf *sb)
 120 {
 121         char *p = sb->buf, *end = sb->buf + sb->len;
 122         for (; p < end; p++)
 123                 *p = tolower(*p);
 124 }
 125
 126 struct strbuf **strbuf_split_buf(const char *str, size_t slen,
 127                                  int terminator, int max)
 128 {
 129         struct strbuf **ret = NULL;
 130         size_t nr = 0, alloc = 0;
 131         struct strbuf *t;
 132
 133         while (slen) {
 134                 int len = slen;
 135                 if (max <= 0 || nr + 1 < max) {
 136                         const char *end = memchr(str, terminator, slen);
 137                         if (end)
 138                                 len = end - str + 1;
 139                 }
 140                 t = xmalloc(sizeof(struct strbuf));
 141                 strbuf_init(t, len);
 142                 strbuf_add(t, str, len);
 143                 ALLOC_GROW(ret, nr + 2, alloc);
 144                 ret[nr++] = t;
 145                 str += len;
 146                 slen -= len;
 147         }
 148         ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 149         ret[nr] = NULL;
 150         return ret;
 151 }
 152
 153 void strbuf_list_free(struct strbuf **sbs)
 154 {
 155         struct strbuf **s = sbs;
 156
 157         while (*s) {
 158                 strbuf_release(*s);
 159                 free(*s++);
 160         }
 161         free(sbs);
 162 }
 163
 164 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 165 {
 166         int len = a->len < b->len ? a->len: b->len;
 167         int cmp = memcmp(a->buf, b->buf, len);
 168         if (cmp)
 169                 return cmp;
 170         return a->len < b->len ? -1: a->len != b->len;
 171 }
 172
 173 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 174                                    const void *data, size_t dlen)
 175 {
 176         if (unsigned_add_overflows(pos, len))
 177                 die("you want to use way too much memory");
 178         if (pos > sb->len)
 179                 die("`pos' is too far after the end of the buffer");
 180         if (pos + len > sb->len)
 181                 die("`pos + len' is too far after the end of the buffer");
 182
 183         if (dlen >= len)
 184                 strbuf_grow(sb, dlen - len);
 185         memmove(sb->buf + pos + dlen,
 186                         sb->buf + pos + len,
 187                         sb->len - pos - len);
 188         memcpy(sb->buf + pos, data, dlen);
 189         strbuf_setlen(sb, sb->len + dlen - len);
 190 }
 191
 192 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 193 {
 194         strbuf_splice(sb, pos, 0, data, len);
 195 }
 196
 197 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 198 {
 199         strbuf_splice(sb, pos, len, NULL, 0);
 200 }
 201
 202 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 203 {
 204         strbuf_grow(sb, len);
 205         memcpy(sb->buf + sb->len, data, len);
 206         strbuf_setlen(sb, sb->len + len);
 207 }
 208
 209 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 210 {
 211         strbuf_grow(sb, len);
 212         memcpy(sb->buf + sb->len, sb->buf + pos, len);
 213         strbuf_setlen(sb, sb->len + len);
 214 }
 215
 216 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 217 {
 218         va_list ap;
 219         va_start(ap, fmt);
 220         strbuf_vaddf(sb, fmt, ap);
 221         va_end(ap);
 222 }
 223
 224 static void add_lines(struct strbuf *out,
 225                         const char *prefix1,
 226                         const char *prefix2,
 227                         const char *buf, size_t size)
 228 {
 229         while (size) {
 230                 const char *prefix;
 231                 const char *next = memchr(buf, '\n', size);
 232                 next = next ? (next + 1) : (buf + size);
 233
 234                 prefix = (prefix2 && buf[0] == '\n') ? prefix2 : prefix1;
 235                 strbuf_addstr(out, prefix);
 236                 strbuf_add(out, buf, next - buf);
 237                 size -= next - buf;
 238                 buf = next;
 239         }
 240         strbuf_complete_line(out);
 241 }
 242
 243 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 244 {
 245         static char prefix1[3];
 246         static char prefix2[2];
 247
 248         if (prefix1[0] != comment_line_char) {
 249                 sprintf(prefix1, "%c ", comment_line_char);
 250                 sprintf(prefix2, "%c", comment_line_char);
 251         }
 252         add_lines(out, prefix1, prefix2, buf, size);
 253 }
 254
 255 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 256 {
 257         va_list params;
 258         struct strbuf buf = STRBUF_INIT;
 259         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 260
 261         va_start(params, fmt);
 262         strbuf_vaddf(&buf, fmt, params);
 263         va_end(params);
 264
 265         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 266         if (incomplete_line)
 267                 sb->buf[--sb->len] = '\0';
 268
 269         strbuf_release(&buf);
 270 }
 271
 272 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 273 {
 274         int len;
 275         va_list cp;
 276
 277         if (!strbuf_avail(sb))
 278                 strbuf_grow(sb, 64);
 279         va_copy(cp, ap);
 280         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 281         va_end(cp);
 282         if (len < 0)
 283                 die("BUG: your vsnprintf is broken (returned %d)", len);
 284         if (len > strbuf_avail(sb)) {
 285                 strbuf_grow(sb, len);
 286                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 287                 if (len > strbuf_avail(sb))
 288                         die("BUG: your vsnprintf is broken (insatiable)");
 289         }
 290         strbuf_setlen(sb, sb->len + len);
 291 }
 292
 293 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 294                    void *context)
 295 {
 296         for (;;) {
 297                 const char *percent;
 298                 size_t consumed;
 299
 300                 percent = strchrnul(format, '%');
 301                 strbuf_add(sb, format, percent - format);
 302                 if (!*percent)
 303                         break;
 304                 format = percent + 1;
 305
 306                 if (*format == '%') {
 307                         strbuf_addch(sb, '%');
 308                         format++;
 309                         continue;
 310                 }
 311
 312                 consumed = fn(sb, format, context);
 313                 if (consumed)
 314                         format += consumed;
 315                 else
 316                         strbuf_addch(sb, '%');
 317         }
 318 }
 319
 320 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 321                 void *context)
 322 {
 323         struct strbuf_expand_dict_entry *e = context;
 324         size_t len;
 325
 326         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 327                 if (!strncmp(placeholder, e->placeholder, len)) {
 328                         if (e->value)
 329                                 strbuf_addstr(sb, e->value);
 330                         return len;
 331                 }
 332         }
 333         return 0;
 334 }
 335
 336 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 337 {
 338         int i, len = src->len;
 339
 340         for (i = 0; i < len; i++) {
 341                 if (src->buf[i] == '%')
 342                         strbuf_addch(dst, '%');
 343                 strbuf_addch(dst, src->buf[i]);
 344         }
 345 }
 346
 347 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 348 {
 349         size_t res;
 350         size_t oldalloc = sb->alloc;
 351
 352         strbuf_grow(sb, size);
 353         res = fread(sb->buf + sb->len, 1, size, f);
 354         if (res > 0)
 355                 strbuf_setlen(sb, sb->len + res);
 356         else if (oldalloc == 0)
 357                 strbuf_release(sb);
 358         return res;
 359 }
 360
 361 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 362 {
 363         size_t oldlen = sb->len;
 364         size_t oldalloc = sb->alloc;
 365
 366         strbuf_grow(sb, hint ? hint : 8192);
 367         for (;;) {
 368                 ssize_t cnt;
 369
 370                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 371                 if (cnt < 0) {
 372                         if (oldalloc == 0)
 373                                 strbuf_release(sb);
 374                         else
 375                                 strbuf_setlen(sb, oldlen);
 376                         return -1;
 377                 }
 378                 if (!cnt)
 379                         break;
 380                 sb->len += cnt;
 381                 strbuf_grow(sb, 8192);
 382         }
 383
 384         sb->buf[sb->len] = '\0';
 385         return sb->len - oldlen;
 386 }
 387
 388 #define STRBUF_MAXLINK (2*PATH_MAX)
 389
 390 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 391 {
 392         size_t oldalloc = sb->alloc;
 393
 394         if (hint < 32)
 395                 hint = 32;
 396
 397         while (hint < STRBUF_MAXLINK) {
 398                 int len;
 399
 400                 strbuf_grow(sb, hint);
 401                 len = readlink(path, sb->buf, hint);
 402                 if (len < 0) {
 403                         if (errno != ERANGE)
 404                                 break;
 405                 } else if (len < hint) {
 406                         strbuf_setlen(sb, len);
 407                         return 0;
 408                 }
 409
 410                 /* .. the buffer was too small - try again */
 411                 hint *= 2;
 412         }
 413         if (oldalloc == 0)
 414                 strbuf_release(sb);
 415         return -1;
 416 }
 417
 418 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 419 {
 420         int ch;
 421
 422         if (feof(fp))
 423                 return EOF;
 424
 425         strbuf_reset(sb);
 426         while ((ch = fgetc(fp)) != EOF) {
 427                 strbuf_grow(sb, 1);
 428                 sb->buf[sb->len++] = ch;
 429                 if (ch == term)
 430                         break;
 431         }
 432         if (ch == EOF && sb->len == 0)
 433                 return EOF;
 434
 435         sb->buf[sb->len] = '\0';
 436         return 0;
 437 }
 438
 439 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 440 {
 441         if (strbuf_getwholeline(sb, fp, term))
 442                 return EOF;
 443         if (sb->buf[sb->len-1] == term)
 444                 strbuf_setlen(sb, sb->len-1);
 445         return 0;
 446 }
 447
 448 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 449 {
 450         strbuf_reset(sb);
 451
 452         while (1) {
 453                 char ch;
 454                 ssize_t len = xread(fd, &ch, 1);
 455                 if (len <= 0)
 456                         return EOF;
 457                 strbuf_addch(sb, ch);
 458                 if (ch == term)
 459                         break;
 460         }
 461         return 0;
 462 }
 463
 464 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 465 {
 466         int fd, len;
 467
 468         fd = open(path, O_RDONLY);
 469         if (fd < 0)
 470                 return -1;
 471         len = strbuf_read(sb, fd, hint);
 472         close(fd);
 473         if (len < 0)
 474                 return -1;
 475
 476         return len;
 477 }
 478
 479 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 480                       const char *buf, size_t size)
 481 {
 482         add_lines(out, prefix, NULL, buf, size);
 483 }
 484
 485 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 486 {
 487         while (*s) {
 488                 size_t len = strcspn(s, "\"<>&");
 489                 strbuf_add(buf, s, len);
 490                 s += len;
 491                 switch (*s) {
 492                 case '"':
 493                         strbuf_addstr(buf, "&quot;");
 494                         break;
 495                 case '<':
 496                         strbuf_addstr(buf, "&lt;");
 497                         break;
 498                 case '>':
 499                         strbuf_addstr(buf, "&gt;");
 500                         break;
 501                 case '&':
 502                         strbuf_addstr(buf, "&amp;");
 503                         break;
 504                 case 0:
 505                         return;
 506                 }
 507                 s++;
 508         }
 509 }
 510
 511 static int is_rfc3986_reserved(char ch)
 512 {
 513         switch (ch) {
 514                 case '!': case '*': case '\'': case '(': case ')': case ';':
 515                 case ':': case '@': case '&': case '=': case '+': case '$':
 516                 case ',': case '/': case '?': case '#': case '[': case ']':
 517                         return 1;
 518         }
 519         return 0;
 520 }
 521
 522 static int is_rfc3986_unreserved(char ch)
 523 {
 524         return isalnum(ch) ||
 525                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 526 }
 527
 528 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 529                                  int reserved)
 530 {
 531         strbuf_grow(sb, len);
 532         while (len--) {
 533                 char ch = *s++;
 534                 if (is_rfc3986_unreserved(ch) ||
 535                     (!reserved && is_rfc3986_reserved(ch)))
 536                         strbuf_addch(sb, ch);
 537                 else
 538                         strbuf_addf(sb, "%%%02x", ch);
 539         }
 540 }
 541
 542 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 543                              int reserved)
 544 {
 545         strbuf_add_urlencode(sb, s, strlen(s), reserved);
 546 }
 547
 548 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 549 {
 550         if (bytes > 1 << 30) {
 551                 strbuf_addf(buf, "%u.%2.2u GiB",
 552                             (int)(bytes >> 30),
 553                             (int)(bytes & ((1 << 30) - 1)) / 10737419);
 554         } else if (bytes > 1 << 20) {
 555                 int x = bytes + 5243;  /* for rounding */
 556                 strbuf_addf(buf, "%u.%2.2u MiB",
 557                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 558         } else if (bytes > 1 << 10) {
 559                 int x = bytes + 5;  /* for rounding */
 560                 strbuf_addf(buf, "%u.%2.2u KiB",
 561                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 562         } else {
 563                 strbuf_addf(buf, "%u bytes", (int)bytes);
 564         }
 565 }
 566
 567 int printf_ln(const char *fmt, ...)
 568 {
 569         int ret;
 570         va_list ap;
 571         va_start(ap, fmt);
 572         ret = vprintf(fmt, ap);
 573         va_end(ap);
 574         if (ret < 0 || putchar('\n') == EOF)
 575                 return -1;
 576         return ret + 1;
 577 }
 578
 579 int fprintf_ln(FILE *fp, const char *fmt, ...)
 580 {
 581         int ret;
 582         va_list ap;
 583         va_start(ap, fmt);
 584         ret = vfprintf(fp, fmt, ap);
 585         va_end(ap);
 586         if (ret < 0 || putc('\n', fp) == EOF)
 587                 return -1;
 588         return ret + 1;
 589 }
 590
 591 char *xstrdup_tolower(const char *string)
 592 {
 593         char *result;
 594         size_t len, i;
 595
 596         len = strlen(string);
 597         result = xmalloc(len + 1);
 598         for (i = 0; i < len; i++)
 599                 result[i] = tolower(string[i]);
 600         result[i] = '\0';
 601         return result;
 602 }
 603
 604 char *xstrvfmt(const char *fmt, va_list ap)
 605 {
 606         struct strbuf buf = STRBUF_INIT;
 607         strbuf_vaddf(&buf, fmt, ap);
 608         return strbuf_detach(&buf, NULL);
 609 }
 610
 611 char *xstrfmt(const char *fmt, ...)
 612 {
 613         va_list ap;
 614         char *ret;
 615
 616         va_start(ap, fmt);
 617         ret = xstrvfmt(fmt, ap);
 618         va_end(ap);
 619
 620         return ret;
 621 }