strbuf.c

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