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