strbuf.c

   1 #include "cache.h"
   2 #include "refs.h"
   3
   4 int prefixcmp(const char *str, const char *prefix)
   5 {
   6         for (; ; str++, prefix++)
   7                 if (!*prefix)
   8                         return 0;
   9                 else if (*str != *prefix)
  10                         return (unsigned char)*prefix - (unsigned char)*str;
  11 }
  12
  13 int suffixcmp(const char *str, const char *suffix)
  14 {
  15         int len = strlen(str), suflen = strlen(suffix);
  16         if (len < suflen)
  17                 return -1;
  18         else
  19                 return strcmp(str + len - suflen, suffix);
  20 }
  21
  22 /*
  23  * Used as the default ->buf value, so that people can always assume
  24  * buf is non NULL and ->buf is NUL terminated even for a freshly
  25  * initialized strbuf.
  26  */
  27 char strbuf_slopbuf[1];
  28
  29 void strbuf_init(struct strbuf *sb, size_t hint)
  30 {
  31         sb->alloc = sb->len = 0;
  32         sb->buf = strbuf_slopbuf;
  33         if (hint)
  34                 strbuf_grow(sb, hint);
  35 }
  36
  37 void strbuf_release(struct strbuf *sb)
  38 {
  39         if (sb->alloc) {
  40                 free(sb->buf);
  41                 strbuf_init(sb, 0);
  42         }
  43 }
  44
  45 char *strbuf_detach(struct strbuf *sb, size_t *sz)
  46 {
  47         char *res;
  48         strbuf_grow(sb, 0);
  49         res = sb->buf;
  50         if (sz)
  51                 *sz = sb->len;
  52         strbuf_init(sb, 0);
  53         return res;
  54 }
  55
  56 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  57 {
  58         strbuf_release(sb);
  59         sb->buf   = buf;
  60         sb->len   = len;
  61         sb->alloc = alloc;
  62         strbuf_grow(sb, 0);
  63         sb->buf[sb->len] = '\0';
  64 }
  65
  66 void strbuf_grow(struct strbuf *sb, size_t extra)
  67 {
  68         int new_buf = !sb->alloc;
  69         if (unsigned_add_overflows(extra, 1) ||
  70             unsigned_add_overflows(sb->len, extra + 1))
  71                 die("you want to use way too much memory");
  72         if (new_buf)
  73                 sb->buf = NULL;
  74         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  75         if (new_buf)
  76                 sb->buf[0] = '\0';
  77 }
  78
  79 void strbuf_trim(struct strbuf *sb)
  80 {
  81         char *b = sb->buf;
  82         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  83                 sb->len--;
  84         while (sb->len > 0 && isspace(*b)) {
  85                 b++;
  86                 sb->len--;
  87         }
  88         memmove(sb->buf, b, sb->len);
  89         sb->buf[sb->len] = '\0';
  90 }
  91 void strbuf_rtrim(struct strbuf *sb)
  92 {
  93         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
  94                 sb->len--;
  95         sb->buf[sb->len] = '\0';
  96 }
  97
  98 void strbuf_ltrim(struct strbuf *sb)
  99 {
 100         char *b = sb->buf;
 101         while (sb->len > 0 && isspace(*b)) {
 102                 b++;
 103                 sb->len--;
 104         }
 105         memmove(sb->buf, b, sb->len);
 106         sb->buf[sb->len] = '\0';
 107 }
 108
 109 struct strbuf **strbuf_split_buf(const char *str, size_t slen,
 110                                  int terminator, int max)
 111 {
 112         struct strbuf **ret = NULL;
 113         size_t nr = 0, alloc = 0;
 114         struct strbuf *t;
 115
 116         while (slen) {
 117                 int len = slen;
 118                 if (max <= 0 || nr + 1 < max) {
 119                         const char *end = memchr(str, terminator, slen);
 120                         if (end)
 121                                 len = end - str + 1;
 122                 }
 123                 t = xmalloc(sizeof(struct strbuf));
 124                 strbuf_init(t, len);
 125                 strbuf_add(t, str, len);
 126                 ALLOC_GROW(ret, nr + 2, alloc);
 127                 ret[nr++] = t;
 128                 str += len;
 129                 slen -= len;
 130         }
 131         ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 132         ret[nr] = NULL;
 133         return ret;
 134 }
 135
 136 void strbuf_list_free(struct strbuf **sbs)
 137 {
 138         struct strbuf **s = sbs;
 139
 140         while (*s) {
 141                 strbuf_release(*s);
 142                 free(*s++);
 143         }
 144         free(sbs);
 145 }
 146
 147 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 148 {
 149         int len = a->len < b->len ? a->len: b->len;
 150         int cmp = memcmp(a->buf, b->buf, len);
 151         if (cmp)
 152                 return cmp;
 153         return a->len < b->len ? -1: a->len != b->len;
 154 }
 155
 156 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 157                                    const void *data, size_t dlen)
 158 {
 159         if (unsigned_add_overflows(pos, len))
 160                 die("you want to use way too much memory");
 161         if (pos > sb->len)
 162                 die("`pos' is too far after the end of the buffer");
 163         if (pos + len > sb->len)
 164                 die("`pos + len' is too far after the end of the buffer");
 165
 166         if (dlen >= len)
 167                 strbuf_grow(sb, dlen - len);
 168         memmove(sb->buf + pos + dlen,
 169                         sb->buf + pos + len,
 170                         sb->len - pos - len);
 171         memcpy(sb->buf + pos, data, dlen);
 172         strbuf_setlen(sb, sb->len + dlen - len);
 173 }
 174
 175 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 176 {
 177         strbuf_splice(sb, pos, 0, data, len);
 178 }
 179
 180 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 181 {
 182         strbuf_splice(sb, pos, len, NULL, 0);
 183 }
 184
 185 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 186 {
 187         strbuf_grow(sb, len);
 188         memcpy(sb->buf + sb->len, data, len);
 189         strbuf_setlen(sb, sb->len + len);
 190 }
 191
 192 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 193 {
 194         strbuf_grow(sb, len);
 195         memcpy(sb->buf + sb->len, sb->buf + pos, len);
 196         strbuf_setlen(sb, sb->len + len);
 197 }
 198
 199 void strbuf_addchars(struct strbuf *sb, int c, size_t n)
 200 {
 201         strbuf_grow(sb, n);
 202         memset(sb->buf + sb->len, c, n);
 203         strbuf_setlen(sb, sb->len + n);
 204 }
 205
 206 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 207 {
 208         va_list ap;
 209         va_start(ap, fmt);
 210         strbuf_vaddf(sb, fmt, ap);
 211         va_end(ap);
 212 }
 213
 214 static void add_lines(struct strbuf *out,
 215                         const char *prefix1,
 216                         const char *prefix2,
 217                         const char *buf, size_t size)
 218 {
 219         while (size) {
 220                 const char *prefix;
 221                 const char *next = memchr(buf, '\n', size);
 222                 next = next ? (next + 1) : (buf + size);
 223
 224                 prefix = (prefix2 && buf[0] == '\n') ? prefix2 : prefix1;
 225                 strbuf_addstr(out, prefix);
 226                 strbuf_add(out, buf, next - buf);
 227                 size -= next - buf;
 228                 buf = next;
 229         }
 230         strbuf_complete_line(out);
 231 }
 232
 233 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 234 {
 235         static char prefix1[3];
 236         static char prefix2[2];
 237
 238         if (prefix1[0] != comment_line_char) {
 239                 sprintf(prefix1, "%c ", comment_line_char);
 240                 sprintf(prefix2, "%c", comment_line_char);
 241         }
 242         add_lines(out, prefix1, prefix2, buf, size);
 243 }
 244
 245 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 246 {
 247         va_list params;
 248         struct strbuf buf = STRBUF_INIT;
 249         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 250
 251         va_start(params, fmt);
 252         strbuf_vaddf(&buf, fmt, params);
 253         va_end(params);
 254
 255         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 256         if (incomplete_line)
 257                 sb->buf[--sb->len] = '\0';
 258
 259         strbuf_release(&buf);
 260 }
 261
 262 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 263 {
 264         int len;
 265         va_list cp;
 266
 267         if (!strbuf_avail(sb))
 268                 strbuf_grow(sb, 64);
 269         va_copy(cp, ap);
 270         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 271         va_end(cp);
 272         if (len < 0)
 273                 die("BUG: your vsnprintf is broken (returned %d)", len);
 274         if (len > strbuf_avail(sb)) {
 275                 strbuf_grow(sb, len);
 276                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 277                 if (len > strbuf_avail(sb))
 278                         die("BUG: your vsnprintf is broken (insatiable)");
 279         }
 280         strbuf_setlen(sb, sb->len + len);
 281 }
 282
 283 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 284                    void *context)
 285 {
 286         for (;;) {
 287                 const char *percent;
 288                 size_t consumed;
 289
 290                 percent = strchrnul(format, '%');
 291                 strbuf_add(sb, format, percent - format);
 292                 if (!*percent)
 293                         break;
 294                 format = percent + 1;
 295
 296                 if (*format == '%') {
 297                         strbuf_addch(sb, '%');
 298                         format++;
 299                         continue;
 300                 }
 301
 302                 consumed = fn(sb, format, context);
 303                 if (consumed)
 304                         format += consumed;
 305                 else
 306                         strbuf_addch(sb, '%');
 307         }
 308 }
 309
 310 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 311                 void *context)
 312 {
 313         struct strbuf_expand_dict_entry *e = context;
 314         size_t len;
 315
 316         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 317                 if (!strncmp(placeholder, e->placeholder, len)) {
 318                         if (e->value)
 319                                 strbuf_addstr(sb, e->value);
 320                         return len;
 321                 }
 322         }
 323         return 0;
 324 }
 325
 326 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 327 {
 328         int i, len = src->len;
 329
 330         for (i = 0; i < len; i++) {
 331                 if (src->buf[i] == '%')
 332                         strbuf_addch(dst, '%');
 333                 strbuf_addch(dst, src->buf[i]);
 334         }
 335 }
 336
 337 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 338 {
 339         size_t res;
 340         size_t oldalloc = sb->alloc;
 341
 342         strbuf_grow(sb, size);
 343         res = fread(sb->buf + sb->len, 1, size, f);
 344         if (res > 0)
 345                 strbuf_setlen(sb, sb->len + res);
 346         else if (oldalloc == 0)
 347                 strbuf_release(sb);
 348         return res;
 349 }
 350
 351 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 352 {
 353         size_t oldlen = sb->len;
 354         size_t oldalloc = sb->alloc;
 355
 356         strbuf_grow(sb, hint ? hint : 8192);
 357         for (;;) {
 358                 ssize_t cnt;
 359
 360                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 361                 if (cnt < 0) {
 362                         if (oldalloc == 0)
 363                                 strbuf_release(sb);
 364                         else
 365                                 strbuf_setlen(sb, oldlen);
 366                         return -1;
 367                 }
 368                 if (!cnt)
 369                         break;
 370                 sb->len += cnt;
 371                 strbuf_grow(sb, 8192);
 372         }
 373
 374         sb->buf[sb->len] = '\0';
 375         return sb->len - oldlen;
 376 }
 377
 378 #define STRBUF_MAXLINK (2*PATH_MAX)
 379
 380 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 381 {
 382         size_t oldalloc = sb->alloc;
 383
 384         if (hint < 32)
 385                 hint = 32;
 386
 387         while (hint < STRBUF_MAXLINK) {
 388                 int len;
 389
 390                 strbuf_grow(sb, hint);
 391                 len = readlink(path, sb->buf, hint);
 392                 if (len < 0) {
 393                         if (errno != ERANGE)
 394                                 break;
 395                 } else if (len < hint) {
 396                         strbuf_setlen(sb, len);
 397                         return 0;
 398                 }
 399
 400                 /* .. the buffer was too small - try again */
 401                 hint *= 2;
 402         }
 403         if (oldalloc == 0)
 404                 strbuf_release(sb);
 405         return -1;
 406 }
 407
 408 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 409 {
 410         int ch;
 411
 412         if (feof(fp))
 413                 return EOF;
 414
 415         strbuf_reset(sb);
 416         while ((ch = fgetc(fp)) != EOF) {
 417                 strbuf_grow(sb, 1);
 418                 sb->buf[sb->len++] = ch;
 419                 if (ch == term)
 420                         break;
 421         }
 422         if (ch == EOF && sb->len == 0)
 423                 return EOF;
 424
 425         sb->buf[sb->len] = '\0';
 426         return 0;
 427 }
 428
 429 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 430 {
 431         if (strbuf_getwholeline(sb, fp, term))
 432                 return EOF;
 433         if (sb->buf[sb->len-1] == term)
 434                 strbuf_setlen(sb, sb->len-1);
 435         return 0;
 436 }
 437
 438 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 439 {
 440         strbuf_reset(sb);
 441
 442         while (1) {
 443                 char ch;
 444                 ssize_t len = xread(fd, &ch, 1);
 445                 if (len <= 0)
 446                         return EOF;
 447                 strbuf_addch(sb, ch);
 448                 if (ch == term)
 449                         break;
 450         }
 451         return 0;
 452 }
 453
 454 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 455 {
 456         int fd, len;
 457
 458         fd = open(path, O_RDONLY);
 459         if (fd < 0)
 460                 return -1;
 461         len = strbuf_read(sb, fd, hint);
 462         close(fd);
 463         if (len < 0)
 464                 return -1;
 465
 466         return len;
 467 }
 468
 469 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 470                       const char *buf, size_t size)
 471 {
 472         add_lines(out, prefix, NULL, buf, size);
 473 }
 474
 475 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 476 {
 477         while (*s) {
 478                 size_t len = strcspn(s, "\"<>&");
 479                 strbuf_add(buf, s, len);
 480                 s += len;
 481                 switch (*s) {
 482                 case '"':
 483                         strbuf_addstr(buf, "&quot;");
 484                         break;
 485                 case '<':
 486                         strbuf_addstr(buf, "&lt;");
 487                         break;
 488                 case '>':
 489                         strbuf_addstr(buf, "&gt;");
 490                         break;
 491                 case '&':
 492                         strbuf_addstr(buf, "&amp;");
 493                         break;
 494                 case 0:
 495                         return;
 496                 }
 497                 s++;
 498         }
 499 }
 500
 501 static int is_rfc3986_reserved(char ch)
 502 {
 503         switch (ch) {
 504                 case '!': case '*': case '\'': case '(': case ')': case ';':
 505                 case ':': case '@': case '&': case '=': case '+': case '$':
 506                 case ',': case '/': case '?': case '#': case '[': case ']':
 507                         return 1;
 508         }
 509         return 0;
 510 }
 511
 512 static int is_rfc3986_unreserved(char ch)
 513 {
 514         return isalnum(ch) ||
 515                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 516 }
 517
 518 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 519                                  int reserved)
 520 {
 521         strbuf_grow(sb, len);
 522         while (len--) {
 523                 char ch = *s++;
 524                 if (is_rfc3986_unreserved(ch) ||
 525                     (!reserved && is_rfc3986_reserved(ch)))
 526                         strbuf_addch(sb, ch);
 527                 else
 528                         strbuf_addf(sb, "%%%02x", ch);
 529         }
 530 }
 531
 532 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 533                              int reserved)
 534 {
 535         strbuf_add_urlencode(sb, s, strlen(s), reserved);
 536 }
 537
 538 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 539 {
 540         if (bytes > 1 << 30) {
 541                 strbuf_addf(buf, "%u.%2.2u GiB",
 542                             (int)(bytes >> 30),
 543                             (int)(bytes & ((1 << 30) - 1)) / 10737419);
 544         } else if (bytes > 1 << 20) {
 545                 int x = bytes + 5243;  /* for rounding */
 546                 strbuf_addf(buf, "%u.%2.2u MiB",
 547                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 548         } else if (bytes > 1 << 10) {
 549                 int x = bytes + 5;  /* for rounding */
 550                 strbuf_addf(buf, "%u.%2.2u KiB",
 551                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 552         } else {
 553                 strbuf_addf(buf, "%u bytes", (int)bytes);
 554         }
 555 }
 556
 557 int printf_ln(const char *fmt, ...)
 558 {
 559         int ret;
 560         va_list ap;
 561         va_start(ap, fmt);
 562         ret = vprintf(fmt, ap);
 563         va_end(ap);
 564         if (ret < 0 || putchar('\n') == EOF)
 565                 return -1;
 566         return ret + 1;
 567 }
 568
 569 int fprintf_ln(FILE *fp, const char *fmt, ...)
 570 {
 571         int ret;
 572         va_list ap;
 573         va_start(ap, fmt);
 574         ret = vfprintf(fp, fmt, ap);
 575         va_end(ap);
 576         if (ret < 0 || putc('\n', fp) == EOF)
 577                 return -1;
 578         return ret + 1;
 579 }