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         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_addf(struct strbuf *sb, const char *fmt, ...)
 200 {
 201         va_list ap;
 202         va_start(ap, fmt);
 203         strbuf_vaddf(sb, fmt, ap);
 204         va_end(ap);
 205 }
 206
 207 static void add_lines(struct strbuf *out,
 208                         const char *prefix1,
 209                         const char *prefix2,
 210                         const char *buf, size_t size)
 211 {
 212         while (size) {
 213                 const char *prefix;
 214                 const char *next = memchr(buf, '\n', size);
 215                 next = next ? (next + 1) : (buf + size);
 216
 217                 prefix = (prefix2 && buf[0] == '\n') ? prefix2 : prefix1;
 218                 strbuf_addstr(out, prefix);
 219                 strbuf_add(out, buf, next - buf);
 220                 size -= next - buf;
 221                 buf = next;
 222         }
 223         strbuf_complete_line(out);
 224 }
 225
 226 void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
 227 {
 228         static char prefix1[3];
 229         static char prefix2[2];
 230
 231         if (prefix1[0] != comment_line_char) {
 232                 sprintf(prefix1, "%c ", comment_line_char);
 233                 sprintf(prefix2, "%c", comment_line_char);
 234         }
 235         add_lines(out, prefix1, prefix2, buf, size);
 236 }
 237
 238 void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
 239 {
 240         va_list params;
 241         struct strbuf buf = STRBUF_INIT;
 242         int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
 243
 244         va_start(params, fmt);
 245         strbuf_vaddf(&buf, fmt, params);
 246         va_end(params);
 247
 248         strbuf_add_commented_lines(sb, buf.buf, buf.len);
 249         if (incomplete_line)
 250                 sb->buf[--sb->len] = '\0';
 251
 252         strbuf_release(&buf);
 253 }
 254
 255 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 256 {
 257         int len;
 258         va_list cp;
 259
 260         if (!strbuf_avail(sb))
 261                 strbuf_grow(sb, 64);
 262         va_copy(cp, ap);
 263         len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
 264         va_end(cp);
 265         if (len < 0)
 266                 die("BUG: your vsnprintf is broken (returned %d)", len);
 267         if (len > strbuf_avail(sb)) {
 268                 strbuf_grow(sb, len);
 269                 len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 270                 if (len > strbuf_avail(sb))
 271                         die("BUG: your vsnprintf is broken (insatiable)");
 272         }
 273         strbuf_setlen(sb, sb->len + len);
 274 }
 275
 276 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 277                    void *context)
 278 {
 279         for (;;) {
 280                 const char *percent;
 281                 size_t consumed;
 282
 283                 percent = strchrnul(format, '%');
 284                 strbuf_add(sb, format, percent - format);
 285                 if (!*percent)
 286                         break;
 287                 format = percent + 1;
 288
 289                 if (*format == '%') {
 290                         strbuf_addch(sb, '%');
 291                         format++;
 292                         continue;
 293                 }
 294
 295                 consumed = fn(sb, format, context);
 296                 if (consumed)
 297                         format += consumed;
 298                 else
 299                         strbuf_addch(sb, '%');
 300         }
 301 }
 302
 303 size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
 304                 void *context)
 305 {
 306         struct strbuf_expand_dict_entry *e = context;
 307         size_t len;
 308
 309         for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
 310                 if (!strncmp(placeholder, e->placeholder, len)) {
 311                         if (e->value)
 312                                 strbuf_addstr(sb, e->value);
 313                         return len;
 314                 }
 315         }
 316         return 0;
 317 }
 318
 319 void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
 320 {
 321         int i, len = src->len;
 322
 323         for (i = 0; i < len; i++) {
 324                 if (src->buf[i] == '%')
 325                         strbuf_addch(dst, '%');
 326                 strbuf_addch(dst, src->buf[i]);
 327         }
 328 }
 329
 330 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 331 {
 332         size_t res;
 333         size_t oldalloc = sb->alloc;
 334
 335         strbuf_grow(sb, size);
 336         res = fread(sb->buf + sb->len, 1, size, f);
 337         if (res > 0)
 338                 strbuf_setlen(sb, sb->len + res);
 339         else if (oldalloc == 0)
 340                 strbuf_release(sb);
 341         return res;
 342 }
 343
 344 ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
 345 {
 346         size_t oldlen = sb->len;
 347         size_t oldalloc = sb->alloc;
 348
 349         strbuf_grow(sb, hint ? hint : 8192);
 350         for (;;) {
 351                 ssize_t cnt;
 352
 353                 cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
 354                 if (cnt < 0) {
 355                         if (oldalloc == 0)
 356                                 strbuf_release(sb);
 357                         else
 358                                 strbuf_setlen(sb, oldlen);
 359                         return -1;
 360                 }
 361                 if (!cnt)
 362                         break;
 363                 sb->len += cnt;
 364                 strbuf_grow(sb, 8192);
 365         }
 366
 367         sb->buf[sb->len] = '\0';
 368         return sb->len - oldlen;
 369 }
 370
 371 #define STRBUF_MAXLINK (2*PATH_MAX)
 372
 373 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 374 {
 375         size_t oldalloc = sb->alloc;
 376
 377         if (hint < 32)
 378                 hint = 32;
 379
 380         while (hint < STRBUF_MAXLINK) {
 381                 int len;
 382
 383                 strbuf_grow(sb, hint);
 384                 len = readlink(path, sb->buf, hint);
 385                 if (len < 0) {
 386                         if (errno != ERANGE)
 387                                 break;
 388                 } else if (len < hint) {
 389                         strbuf_setlen(sb, len);
 390                         return 0;
 391                 }
 392
 393                 /* .. the buffer was too small - try again */
 394                 hint *= 2;
 395         }
 396         if (oldalloc == 0)
 397                 strbuf_release(sb);
 398         return -1;
 399 }
 400
 401 int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
 402 {
 403         int ch;
 404
 405         if (feof(fp))
 406                 return EOF;
 407
 408         strbuf_reset(sb);
 409         while ((ch = fgetc(fp)) != EOF) {
 410                 strbuf_grow(sb, 1);
 411                 sb->buf[sb->len++] = ch;
 412                 if (ch == term)
 413                         break;
 414         }
 415         if (ch == EOF && sb->len == 0)
 416                 return EOF;
 417
 418         sb->buf[sb->len] = '\0';
 419         return 0;
 420 }
 421
 422 int strbuf_getline(struct strbuf *sb, FILE *fp, int term)
 423 {
 424         if (strbuf_getwholeline(sb, fp, term))
 425                 return EOF;
 426         if (sb->buf[sb->len-1] == term)
 427                 strbuf_setlen(sb, sb->len-1);
 428         return 0;
 429 }
 430
 431 int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
 432 {
 433         strbuf_reset(sb);
 434
 435         while (1) {
 436                 char ch;
 437                 ssize_t len = xread(fd, &ch, 1);
 438                 if (len <= 0)
 439                         return EOF;
 440                 strbuf_addch(sb, ch);
 441                 if (ch == term)
 442                         break;
 443         }
 444         return 0;
 445 }
 446
 447 int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 448 {
 449         int fd, len;
 450
 451         fd = open(path, O_RDONLY);
 452         if (fd < 0)
 453                 return -1;
 454         len = strbuf_read(sb, fd, hint);
 455         close(fd);
 456         if (len < 0)
 457                 return -1;
 458
 459         return len;
 460 }
 461
 462 void strbuf_add_lines(struct strbuf *out, const char *prefix,
 463                       const char *buf, size_t size)
 464 {
 465         add_lines(out, prefix, NULL, buf, size);
 466 }
 467
 468 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 469 {
 470         while (*s) {
 471                 size_t len = strcspn(s, "\"<>&");
 472                 strbuf_add(buf, s, len);
 473                 s += len;
 474                 switch (*s) {
 475                 case '"':
 476                         strbuf_addstr(buf, "&quot;");
 477                         break;
 478                 case '<':
 479                         strbuf_addstr(buf, "&lt;");
 480                         break;
 481                 case '>':
 482                         strbuf_addstr(buf, "&gt;");
 483                         break;
 484                 case '&':
 485                         strbuf_addstr(buf, "&amp;");
 486                         break;
 487                 case 0:
 488                         return;
 489                 }
 490                 s++;
 491         }
 492 }
 493
 494 static int is_rfc3986_reserved(char ch)
 495 {
 496         switch (ch) {
 497                 case '!': case '*': case '\'': case '(': case ')': case ';':
 498                 case ':': case '@': case '&': case '=': case '+': case '$':
 499                 case ',': case '/': case '?': case '#': case '[': case ']':
 500                         return 1;
 501         }
 502         return 0;
 503 }
 504
 505 static int is_rfc3986_unreserved(char ch)
 506 {
 507         return isalnum(ch) ||
 508                 ch == '-' || ch == '_' || ch == '.' || ch == '~';
 509 }
 510
 511 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 512                                  int reserved)
 513 {
 514         strbuf_grow(sb, len);
 515         while (len--) {
 516                 char ch = *s++;
 517                 if (is_rfc3986_unreserved(ch) ||
 518                     (!reserved && is_rfc3986_reserved(ch)))
 519                         strbuf_addch(sb, ch);
 520                 else
 521                         strbuf_addf(sb, "%%%02x", ch);
 522         }
 523 }
 524
 525 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
 526                              int reserved)
 527 {
 528         strbuf_add_urlencode(sb, s, strlen(s), reserved);
 529 }
 530
 531 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
 532 {
 533         if (bytes > 1 << 30) {
 534                 strbuf_addf(buf, "%u.%2.2u GiB",
 535                             (int)(bytes >> 30),
 536                             (int)(bytes & ((1 << 30) - 1)) / 10737419);
 537         } else if (bytes > 1 << 20) {
 538                 int x = bytes + 5243;  /* for rounding */
 539                 strbuf_addf(buf, "%u.%2.2u MiB",
 540                             x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
 541         } else if (bytes > 1 << 10) {
 542                 int x = bytes + 5;  /* for rounding */
 543                 strbuf_addf(buf, "%u.%2.2u KiB",
 544                             x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
 545         } else {
 546                 strbuf_addf(buf, "%u bytes", (int)bytes);
 547         }
 548 }
 549
 550 int printf_ln(const char *fmt, ...)
 551 {
 552         int ret;
 553         va_list ap;
 554         va_start(ap, fmt);
 555         ret = vprintf(fmt, ap);
 556         va_end(ap);
 557         if (ret < 0 || putchar('\n') == EOF)
 558                 return -1;
 559         return ret + 1;
 560 }
 561
 562 int fprintf_ln(FILE *fp, const char *fmt, ...)
 563 {
 564         int ret;
 565         va_list ap;
 566         va_start(ap, fmt);
 567         ret = vfprintf(fp, fmt, ap);
 568         va_end(ap);
 569         if (ret < 0 || putc('\n', fp) == EOF)
 570                 return -1;
 571         return ret + 1;
 572 }