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 prefixcmp(const char *str, const char *prefix)
  14 {
  15         for (; ; str++, prefix++)
  16                 if (!*prefix)
  17                         return 0;
  18                 else if (*str != *prefix)
  19                         return (unsigned char)*prefix - (unsigned char)*str;
  20 }
  21
  22 int ends_with(const char *str, const char *suffix)
  23 {
  24         int len = strlen(str), suflen = strlen(suffix);
  25         if (len < suflen)
  26                 return 0;
  27         else
  28                 return !strcmp(str + len - suflen, suffix);
  29 }
  30
  31 int suffixcmp(const char *str, const char *suffix)
  32 {
  33         int len = strlen(str), suflen = strlen(suffix);
  34         if (len < suflen)
  35                 return -1;
  36         else
  37                 return strcmp(str + len - suflen, suffix);
  38 }
  39
  40 /*
  41  * Used as the default ->buf value, so that people can always assume
  42  * buf is non NULL and ->buf is NUL terminated even for a freshly
  43  * initialized strbuf.
  44  */
  45 char strbuf_slopbuf[1];
  46
  47 void strbuf_init(struct strbuf *sb, size_t hint)
  48 {
  49         sb->alloc = sb->len = 0;
  50         sb->buf = strbuf_slopbuf;
  51         if (hint)
  52                 strbuf_grow(sb, hint);
  53 }
  54
  55 void strbuf_release(struct strbuf *sb)
  56 {
  57         if (sb->alloc) {
  58                 free(sb->buf);
  59                 strbuf_init(sb, 0);
  60         }
  61 }
  62
  63 char *strbuf_detach(struct strbuf *sb, size_t *sz)
  64 {
  65         char *res;
  66         strbuf_grow(sb, 0);
  67         res = sb->buf;
  68         if (sz)
  69                 *sz = sb->len;
  70         strbuf_init(sb, 0);
  71         return res;
  72 }
  73
  74 void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
  75 {
  76         strbuf_release(sb);
  77         sb->buf   = buf;
  78         sb->len   = len;
  79         sb->alloc = alloc;
  80         strbuf_grow(sb, 0);
  81         sb->buf[sb->len] = '\0';
  82 }
  83
  84 void strbuf_grow(struct strbuf *sb, size_t extra)
  85 {
  86         int new_buf = !sb->alloc;
  87         if (unsigned_add_overflows(extra, 1) ||
  88             unsigned_add_overflows(sb->len, extra + 1))
  89                 die("you want to use way too much memory");
  90         if (new_buf)
  91                 sb->buf = NULL;
  92         ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
  93         if (new_buf)
  94                 sb->buf[0] = '\0';
  95 }
  96
  97 void strbuf_trim(struct strbuf *sb)
  98 {
  99         char *b = sb->buf;
 100         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
 101                 sb->len--;
 102         while (sb->len > 0 && isspace(*b)) {
 103                 b++;
 104                 sb->len--;
 105         }
 106         memmove(sb->buf, b, sb->len);
 107         sb->buf[sb->len] = '\0';
 108 }
 109 void strbuf_rtrim(struct strbuf *sb)
 110 {
 111         while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
 112                 sb->len--;
 113         sb->buf[sb->len] = '\0';
 114 }
 115
 116 void strbuf_ltrim(struct strbuf *sb)
 117 {
 118         char *b = sb->buf;
 119         while (sb->len > 0 && isspace(*b)) {
 120                 b++;
 121                 sb->len--;
 122         }
 123         memmove(sb->buf, b, sb->len);
 124         sb->buf[sb->len] = '\0';
 125 }
 126
 127 struct strbuf **strbuf_split_buf(const char *str, size_t slen,
 128                                  int terminator, int max)
 129 {
 130         struct strbuf **ret = NULL;
 131         size_t nr = 0, alloc = 0;
 132         struct strbuf *t;
 133
 134         while (slen) {
 135                 int len = slen;
 136                 if (max <= 0 || nr + 1 < max) {
 137                         const char *end = memchr(str, terminator, slen);
 138                         if (end)
 139                                 len = end - str + 1;
 140                 }
 141                 t = xmalloc(sizeof(struct strbuf));
 142                 strbuf_init(t, len);
 143                 strbuf_add(t, str, len);
 144                 ALLOC_GROW(ret, nr + 2, alloc);
 145                 ret[nr++] = t;
 146                 str += len;
 147                 slen -= len;
 148         }
 149         ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 150         ret[nr] = NULL;
 151         return ret;
 152 }
 153
 154 void strbuf_list_free(struct strbuf **sbs)
 155 {
 156         struct strbuf **s = sbs;
 157
 158         while (*s) {
 159                 strbuf_release(*s);
 160                 free(*s++);
 161         }
 162         free(sbs);
 163 }
 164
 165 int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
 166 {
 167         int len = a->len < b->len ? a->len: b->len;
 168         int cmp = memcmp(a->buf, b->buf, len);
 169         if (cmp)
 170                 return cmp;
 171         return a->len < b->len ? -1: a->len != b->len;
 172 }
 173
 174 void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
 175                                    const void *data, size_t dlen)
 176 {
 177         if (unsigned_add_overflows(pos, len))
 178                 die("you want to use way too much memory");
 179         if (pos > sb->len)
 180                 die("`pos' is too far after the end of the buffer");
 181         if (pos + len > sb->len)
 182                 die("`pos + len' is too far after the end of the buffer");
 183
 184         if (dlen >= len)
 185                 strbuf_grow(sb, dlen - len);
 186         memmove(sb->buf + pos + dlen,
 187                         sb->buf + pos + len,
 188                         sb->len - pos - len);
 189         memcpy(sb->buf + pos, data, dlen);
 190         strbuf_setlen(sb, sb->len + dlen - len);
 191 }
 192
 193 void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
 194 {
 195         strbuf_splice(sb, pos, 0, data, len);
 196 }
 197
 198 void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
 199 {
 200         strbuf_splice(sb, pos, len, NULL, 0);
 201 }
 202
 203 void strbuf_add(struct strbuf *sb, const void *data, size_t len)
 204 {
 205         strbuf_grow(sb, len);
 206         memcpy(sb->buf + sb->len, data, len);
 207         strbuf_setlen(sb, sb->len + len);
 208 }
 209
 210 void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 211 {
 212         strbuf_grow(sb, len);
 213         memcpy(sb->buf + sb->len, sb->buf + pos, len);
 214         strbuf_setlen(sb, sb->len + len);
 215 }
 216
 217 void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 218 {
 219         va_list ap;
 220         va_start(ap, fmt);
 221         strbuf_vaddf(sb, fmt, ap);
 222         va_end(ap);
 223 }
 224
 225 static void add_lines(struct strbuf *out,
 226                         const char *prefix1,
 227                         const char *prefix2,
 228                         const char *buf, size_t size)
 229 {
 230         while (size) {
 231                 const char *prefix;
 232                 const char *next = memchr(buf, '\n', size);
 233                 next = next ? (next + 1) : (buf + size);
 234
 235                 prefix = (prefix2 && buf[0] == '\n') ? prefix2 : prefix1;
 236                 strbuf_addstr(out, prefix);
 237                 strbuf_add(out, buf, next - buf);
 238                 size -= next - buf;
 239                 buf = next;
 240         }
 241         strbuf_complete_line(out);
 242 }
 243
 244 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 245 {
 246         static char prefix1[3];
 247         static char prefix2[2];
 248
 249         if (prefix1[0] != comment_line_char) {
 250                 sprintf(prefix1, "%c ", comment_line_char);
 251                 sprintf(prefix2, "%c", comment_line_char);
 252         }
 253         add_lines(out, prefix1, prefix2, buf, size);
 254 }
 255
 256 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 257 {
 258         va_list params;
 259         struct strbuf buf = STRBUF_INIT;
 260         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 261
 262         va_start(params, fmt);
 263         strbuf_vaddf(&buf, fmt, params);
 264         va_end(params);
 265
 266         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 267         if (incomplete_line)
 268                 sb->buf[--sb->len] = '\0';
 269
 270         strbuf_release(&buf);
 271 }
 272
 273 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 274 {
 275         int len;
 276         va_list cp;
 277
 278         if (!strbuf_avail(sb))
 279                 strbuf_grow(sb, 64);
 280         va_copy(cp, ap);
 281         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 282         va_end(cp);
 283         if (len < 0)
 284                 die("BUG: your vsnprintf is broken (returned %d)", len);
 285         if (len > strbuf_avail(sb)) {
 286                 strbuf_grow(sb, len);
 287                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 288                 if (len > strbuf_avail(sb))
 289                         die("BUG: your vsnprintf is broken (insatiable)");
 290         }
 291         strbuf_setlen(sb, sb->len + len);
 292 }
 293
 294 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 295                    void *context)
 296 {
 297         for (;;) {
 298                 const char *percent;
 299                 size_t consumed;
 300
 301                 percent = strchrnul(format, '%');
 302                 strbuf_add(sb, format, percent - format);
 303                 if (!*percent)
 304                         break;
 305                 format = percent + 1;
 306
 307                 if (*format == '%') {
 308                         strbuf_addch(sb, '%');
 309                         format++;
 310                         continue;
 311                 }
 312
 313                 consumed = fn(sb, format, context);
 314                 if (consumed)
 315                         format += consumed;
 316                 else
 317                         strbuf_addch(sb, '%');
 318         }
 319 }
 320
 321 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 322                 void *context)
 323 {
 324         struct strbuf_expand_dict_entry *e = context;
 325         size_t len;
 326
 327         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 328                 if (!strncmp(placeholder, e->placeholder, len)) {
 329                         if (e->value)
 330                                 strbuf_addstr(sb, e->value);
 331                         return len;
 332                 }
 333         }
 334         return 0;
 335 }
 336
 337 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 338 {
 339         int i, len = src->len;
 340
 341         for (i = 0; i < len; i++) {
 342                 if (src->buf[i] == '%')
 343                         strbuf_addch(dst, '%');
 344                 strbuf_addch(dst, src->buf[i]);
 345         }
 346 }
 347
 348 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 349 {
 350         size_t res;
 351         size_t oldalloc = sb->alloc;
 352
 353         strbuf_grow(sb, size);
 354         res = fread(sb->buf + sb->len, 1, size, f);
 355         if (res > 0)
 356                 strbuf_setlen(sb, sb->len + res);
 357         else if (oldalloc == 0)
 358                 strbuf_release(sb);
 359         return res;
 360 }
 361
 362 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 363 {
 364         size_t oldlen = sb->len;
 365         size_t oldalloc = sb->alloc;
 366
 367         strbuf_grow(sb, hint ? hint : 8192);
 368         for (;;) {
 369                 ssize_t cnt;
 370
 371                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 372                 if (cnt < 0) {
 373                         if (oldalloc == 0)
 374                                 strbuf_release(sb);
 375                         else
 376                                 strbuf_setlen(sb, oldlen);
 377                         return -1;
 378                 }
 379                 if (!cnt)
 380                         break;
 381                 sb->len += cnt;
 382                 strbuf_grow(sb, 8192);
 383         }
 384
 385         sb->buf[sb->len] = '\0';
 386         return sb->len - oldlen;
 387 }
 388
 389 #define STRBUF_MAXLINK (2*PATH_MAX)
 390
 391 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 392 {
 393         size_t oldalloc = sb->alloc;
 394
 395         if (hint < 32)
 396                 hint = 32;
 397
 398         while (hint < STRBUF_MAXLINK) {
 399                 int len;
 400
 401                 strbuf_grow(sb, hint);
 402                 len = readlink(path, sb->buf, hint);
 403                 if (len < 0) {
 404                         if (errno != ERANGE)
 405                                 break;
 406                 } else if (len < hint) {
 407                         strbuf_setlen(sb, len);
 408                         return 0;
 409                 }
 410
 411                 /* .. the buffer was too small - try again */
 412                 hint *= 2;
 413         }
 414         if (oldalloc == 0)
 415                 strbuf_release(sb);
 416         return -1;
 417 }
 418
 419 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 420 {
 421         int ch;
 422
 423         if (feof(fp))
 424                 return EOF;
 425
 426         strbuf_reset(sb);
 427         while ((ch = fgetc(fp)) != EOF) {
 428                 strbuf_grow(sb, 1);
 429                 sb->buf[sb->len++] = ch;
 430                 if (ch == term)
 431                         break;
 432         }
 433         if (ch == EOF && sb->len == 0)
 434                 return EOF;
 435
 436         sb->buf[sb->len] = '\0';
 437         return 0;
 438 }
 439
 440 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 441 {
 442         if (strbuf_getwholeline(sb, fp, term))
 443                 return EOF;
 444         if (sb->buf[sb->len-1] == term)
 445                 strbuf_setlen(sb, sb->len-1);
 446         return 0;
 447 }
 448
 449 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 450 {
 451         strbuf_reset(sb);
 452
 453         while (1) {
 454                 char ch;
 455                 ssize_t len = xread(fd, &ch, 1);
 456                 if (len <= 0)
 457                         return EOF;
 458                 strbuf_addch(sb, ch);
 459                 if (ch == term)
 460                         break;
 461         }
 462         return 0;
 463 }
 464
 465 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 466 {
 467         int fd, len;
 468
 469         fd = open(path, O_RDONLY);
 470         if (fd < 0)
 471                 return -1;
 472         len = strbuf_read(sb, fd, hint);
 473         close(fd);
 474         if (len < 0)
 475                 return -1;
 476
 477         return len;
 478 }
 479
 480 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 481                       const char *buf, size_t size)
 482 {
 483         add_lines(out, prefix, NULL, buf, size);
 484 }
 485
 486 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 487 {
 488         while (*s) {
 489                 size_t len = strcspn(s, "\"<>&");
 490                 strbuf_add(buf, s, len);
 491                 s += len;
 492                 switch (*s) {
 493                 case '"':
 494                         strbuf_addstr(buf, "&quot;");
 495                         break;
 496                 case '<':
 497                         strbuf_addstr(buf, "&lt;");
 498                         break;
 499                 case '>':
 500                         strbuf_addstr(buf, "&gt;");
 501                         break;
 502                 case '&':
 503                         strbuf_addstr(buf, "&amp;");
 504                         break;
 505                 case 0:
 506                         return;
 507                 }
 508                 s++;
 509         }
 510 }
 511
 512 static int is_rfc3986_reserved(char ch)
 513 {
 514         switch (ch) {
 515                 case '!': case '*': case '\'': case '(': case ')': case ';':
 516                 case ':': case '@': case '&': case '=': case '+': case '$':
 517                 case ',': case '/': case '?': case '#': case '[': case ']':
 518                         return 1;
 519         }
 520         return 0;
 521 }
 522
 523 static int is_rfc3986_unreserved(char ch)
 524 {
 525         return isalnum(ch) ||
 526                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 527 }
 528
 529 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 530                                  int reserved)
 531 {
 532         strbuf_grow(sb, len);
 533         while (len--) {
 534                 char ch = *s++;
 535                 if (is_rfc3986_unreserved(ch) ||
 536                     (!reserved && is_rfc3986_reserved(ch)))
 537                         strbuf_addch(sb, ch);
 538                 else
 539                         strbuf_addf(sb, "%%%02x", ch);
 540         }
 541 }
 542
 543 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 544                              int reserved)
 545 {
 546         strbuf_add_urlencode(sb, s, strlen(s), reserved);
 547 }
 548
 549 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 550 {
 551         if (bytes > 1 << 30) {
 552                 strbuf_addf(buf, "%u.%2.2u GiB",
 553                             (int)(bytes >> 30),
 554                             (int)(bytes & ((1 << 30) - 1)) / 10737419);
 555         } else if (bytes > 1 << 20) {
 556                 int x = bytes + 5243;  /* for rounding */
 557                 strbuf_addf(buf, "%u.%2.2u MiB",
 558                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 559         } else if (bytes > 1 << 10) {
 560                 int x = bytes + 5;  /* for rounding */
 561                 strbuf_addf(buf, "%u.%2.2u KiB",
 562                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 563         } else {
 564                 strbuf_addf(buf, "%u bytes", (int)bytes);
 565         }
 566 }
 567
 568 int printf_ln(const char *fmt, ...)
 569 {
 570         int ret;
 571         va_list ap;
 572         va_start(ap, fmt);
 573         ret = vprintf(fmt, ap);
 574         va_end(ap);
 575         if (ret < 0 || putchar('\n') == EOF)
 576                 return -1;
 577         return ret + 1;
 578 }
 579
 580 int fprintf_ln(FILE *fp, const char *fmt, ...)
 581 {
 582         int ret;
 583         va_list ap;
 584         va_start(ap, fmt);
 585         ret = vfprintf(fp, fmt, ap);
 586         va_end(ap);
 587         if (ret < 0 || putc('\n', fp) == EOF)
 588                 return -1;
 589         return ret + 1;
 590 }