| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: dstr.c,v 1.2 1998/12/15 23:53:22 mdw Exp $ |
| 4 | * |
| 5 | * Handle dynamically growing strings |
| 6 | * |
| 7 | * (c) 1998 Straylight/Edgeware |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of the mLib utilities library. |
| 13 | * |
| 14 | * mLib is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2 of the License, or |
| 17 | * (at your option) any later version. |
| 18 | * |
| 19 | * mLib is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License |
| 25 | * along with mLib; if not, write to the Free Software Foundation, |
| 26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 27 | */ |
| 28 | |
| 29 | /*----- Revision history --------------------------------------------------* |
| 30 | * |
| 31 | * $Log: dstr.c,v $ |
| 32 | * Revision 1.2 1998/12/15 23:53:22 mdw |
| 33 | * New functions `dstr_putf' and `dstr_vputf' which do `printf'-style |
| 34 | * formatting in a safe way. |
| 35 | * |
| 36 | * Revision 1.1.1.1 1998/06/17 23:44:42 mdw |
| 37 | * Initial version of mLib |
| 38 | * |
| 39 | */ |
| 40 | |
| 41 | /*----- Header files ------------------------------------------------------*/ |
| 42 | |
| 43 | #include <ctype.h> |
| 44 | #include <float.h> |
| 45 | #include <math.h> |
| 46 | #include <stdarg.h> |
| 47 | #include <stdio.h> |
| 48 | #include <stdlib.h> |
| 49 | #include <string.h> |
| 50 | |
| 51 | #include "alloc.h" |
| 52 | #include "dstr.h" |
| 53 | |
| 54 | /*----- Tunable constants -------------------------------------------------*/ |
| 55 | |
| 56 | #define DSTR_INITSZ 256 /* Initial buffer size */ |
| 57 | #define DSTR_INCSZ 4096 /* Threshhold for doubling */ |
| 58 | #define DSTR_PUTFSTEP 64 /* Buffer size for @putf@ */ |
| 59 | |
| 60 | /*----- Main code ---------------------------------------------------------*/ |
| 61 | |
| 62 | /* --- @dstr_create@ --- * |
| 63 | * |
| 64 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 65 | * |
| 66 | * Returns: --- |
| 67 | * |
| 68 | * Use: Initialises a dynamic string. |
| 69 | */ |
| 70 | |
| 71 | void dstr_create(dstr *d) |
| 72 | { |
| 73 | d->sz = 0; |
| 74 | d->len = 0; |
| 75 | d->buf = 0; |
| 76 | } |
| 77 | |
| 78 | /* --- @dstr_destroy@ --- * |
| 79 | * |
| 80 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 81 | * |
| 82 | * Returns: --- |
| 83 | * |
| 84 | * Use: Reclaims the space used by a dynamic string. |
| 85 | */ |
| 86 | |
| 87 | void dstr_destroy(dstr *d) |
| 88 | { |
| 89 | if (d->buf) |
| 90 | free(d->buf); |
| 91 | d->buf = 0; |
| 92 | d->len = 0; |
| 93 | d->sz = 0; |
| 94 | } |
| 95 | |
| 96 | /* --- @dstr_reset@ --- * |
| 97 | * |
| 98 | * Arguments: @dstr *d@ = pointer to a dynaimc string block |
| 99 | * |
| 100 | * Returns: --- |
| 101 | * |
| 102 | * Use: Resets a string so that new data gets put at the beginning. |
| 103 | */ |
| 104 | |
| 105 | void dstr_reset(dstr *d) |
| 106 | { |
| 107 | d->len = 0; |
| 108 | } |
| 109 | |
| 110 | /* --- @dstr_ensure@ --- * |
| 111 | * |
| 112 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 113 | * @size_t sz@ = amount of free space to ensure |
| 114 | * |
| 115 | * Returns: --- |
| 116 | * |
| 117 | * Use: Ensures that at least @sz@ bytes are available in the |
| 118 | * given string. |
| 119 | */ |
| 120 | |
| 121 | void dstr_ensure(dstr *d, size_t sz) |
| 122 | { |
| 123 | size_t rq = d->len + sz; |
| 124 | size_t nsz; |
| 125 | |
| 126 | /* --- If we have enough space, just leave it --- */ |
| 127 | |
| 128 | if (rq <= d->sz) |
| 129 | return; |
| 130 | |
| 131 | /* --- Grow the buffer --- * |
| 132 | * |
| 133 | * For small buffers, just double the size. For big buffers, make them |
| 134 | * a multiple of some suitably large chunk size. |
| 135 | */ |
| 136 | |
| 137 | nsz = d->sz; |
| 138 | |
| 139 | do { |
| 140 | if (nsz == 0) |
| 141 | nsz = DSTR_INITSZ; |
| 142 | else if (d->sz < 0x1000) |
| 143 | nsz <<= 1; |
| 144 | else |
| 145 | nsz = (rq + 0x0fff) & ~0x0fff; |
| 146 | } while (rq > nsz); |
| 147 | |
| 148 | if (d->buf) |
| 149 | d->buf = xrealloc(d->buf, nsz); |
| 150 | else |
| 151 | d->buf = xmalloc(nsz); |
| 152 | d->sz = nsz; |
| 153 | } |
| 154 | |
| 155 | /* --- @dstr_putc@ --- * |
| 156 | * |
| 157 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 158 | * @char ch@ = character to append |
| 159 | * |
| 160 | * Returns: --- |
| 161 | * |
| 162 | * Use: Appends a character to a string. |
| 163 | */ |
| 164 | |
| 165 | void dstr_putc(dstr *d, char ch) |
| 166 | { |
| 167 | DPUTC(d, ch); |
| 168 | } |
| 169 | |
| 170 | /* --- @dstr_putz@ --- * |
| 171 | * |
| 172 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 173 | * |
| 174 | * Returns: --- |
| 175 | * |
| 176 | * Use: Appends a null byte to a string. The null byte does not |
| 177 | * contribute to the string's length, and will be overwritten |
| 178 | * by subsequent `put' operations. |
| 179 | */ |
| 180 | |
| 181 | void dstr_putz(dstr *d) |
| 182 | { |
| 183 | DPUTZ(d); |
| 184 | } |
| 185 | |
| 186 | /* --- @dstr_puts@ --- * |
| 187 | * |
| 188 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 189 | * @const char *s@ = pointer to string to append |
| 190 | * |
| 191 | * Returns: --- |
| 192 | * |
| 193 | * Use: Appends a character string to a string. A trailing null |
| 194 | * byte is added, as for @dstr_putz@. |
| 195 | */ |
| 196 | |
| 197 | void dstr_puts(dstr *d, const char *s) |
| 198 | { |
| 199 | DPUTS(d, s); |
| 200 | } |
| 201 | |
| 202 | /* --- @dstr_vputf@ --- * |
| 203 | * |
| 204 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 205 | * @const char *p@ = pointer to @printf@-style format string |
| 206 | * @va_list ap@ = argument handle |
| 207 | * |
| 208 | * Returns: --- |
| 209 | * |
| 210 | * Use: As for @dstr_putf@, but may be used as a back-end to user- |
| 211 | * supplied functions with @printf@-style interfaces. |
| 212 | */ |
| 213 | |
| 214 | int dstr_vputf(dstr *d, const char *p, va_list ap) |
| 215 | { |
| 216 | const char *q = p; |
| 217 | size_t n = d->len; |
| 218 | size_t sz; |
| 219 | |
| 220 | while (*p) { |
| 221 | unsigned f; |
| 222 | int wd, prec; |
| 223 | dstr dd; |
| 224 | |
| 225 | enum { |
| 226 | f_short = 1, |
| 227 | f_long = 2, |
| 228 | f_Long = 4, |
| 229 | f_wd = 8, |
| 230 | f_prec = 16 |
| 231 | }; |
| 232 | |
| 233 | /* --- Most stuff gets passed on through --- */ |
| 234 | |
| 235 | if (*p != '%') { |
| 236 | p++; |
| 237 | continue; |
| 238 | } |
| 239 | |
| 240 | /* --- Dump out what's between @q@ and @p@ --- */ |
| 241 | |
| 242 | DPUTM(d, q, p - q); |
| 243 | p++; |
| 244 | |
| 245 | /* --- Sort out the various silly flags and things --- */ |
| 246 | |
| 247 | dstr_create(&dd); |
| 248 | DPUTC(&dd, '%'); |
| 249 | f = 0; |
| 250 | sz = DSTR_PUTFSTEP; |
| 251 | |
| 252 | for (;;) { |
| 253 | switch (*p) { |
| 254 | |
| 255 | /* --- Various simple flags --- */ |
| 256 | |
| 257 | case '+': |
| 258 | case '-': |
| 259 | case '#': |
| 260 | case '0': |
| 261 | goto putch; |
| 262 | case 'h': |
| 263 | f |= f_short; |
| 264 | goto putch; |
| 265 | case 'l': |
| 266 | f |= f_long; |
| 267 | goto putch; |
| 268 | case 'L': |
| 269 | f |= f_Long; |
| 270 | goto putch; |
| 271 | case 0: |
| 272 | goto finished; |
| 273 | |
| 274 | /* --- Field widths and precision specifiers --- */ |
| 275 | |
| 276 | { |
| 277 | int *ip; |
| 278 | |
| 279 | case '.': |
| 280 | DPUTC(&dd, '.'); |
| 281 | ip = ≺ |
| 282 | f |= f_prec; |
| 283 | goto getnum; |
| 284 | case '*': |
| 285 | ip = &wd; |
| 286 | f |= f_wd; |
| 287 | goto getnum; |
| 288 | default: |
| 289 | if (isdigit((unsigned char)*p)) { |
| 290 | f |= f_prec; |
| 291 | ip = &wd; |
| 292 | goto getnum; |
| 293 | } |
| 294 | DPUTC(d, *p); |
| 295 | goto formatted; |
| 296 | getnum: |
| 297 | *ip = 0; |
| 298 | if (*p == '*') { |
| 299 | *ip = va_arg(ap, int); |
| 300 | DENSURE(&dd, DSTR_PUTFSTEP); |
| 301 | dd.len += sprintf(dd.buf + dd.len, "%i", *ip); |
| 302 | } else { |
| 303 | *ip = *p + '0'; |
| 304 | DPUTC(&dd, *p); |
| 305 | p++; |
| 306 | while (isdigit((unsigned char)*p)) { |
| 307 | DPUTC(&dd, *p); |
| 308 | *ip = 10 * *ip + *p++ + '0'; |
| 309 | } |
| 310 | } |
| 311 | break; |
| 312 | } |
| 313 | |
| 314 | /* --- Output formatting --- */ |
| 315 | |
| 316 | case 'd': case 'i': case 'x': case 'X': case 'o': case 'u': |
| 317 | DPUTC(&dd, *p); |
| 318 | DPUTZ(&dd); |
| 319 | if ((f & f_prec) && prec + 16 > sz) |
| 320 | sz = prec + 16; |
| 321 | if ((f & f_wd) && wd + 1> sz) |
| 322 | sz = wd + 1; |
| 323 | DENSURE(d, sz); |
| 324 | if (f & f_long) |
| 325 | d->len += sprintf(d->buf + d->len, dd.buf, |
| 326 | va_arg(ap, unsigned long)); |
| 327 | else |
| 328 | d->len += sprintf(d->buf + d->len, dd.buf, |
| 329 | va_arg(ap, unsigned int)); |
| 330 | goto formatted; |
| 331 | |
| 332 | case 'e': case 'E': case 'f': case 'F': case 'g': case 'G': |
| 333 | DPUTC(&dd, *p); |
| 334 | DPUTZ(&dd); |
| 335 | if (*p == 'f') { |
| 336 | size_t mx = (f & f_Long ? LDBL_MAX_10_EXP : DBL_MAX_10_EXP) + 16; |
| 337 | if (mx > sz) |
| 338 | sz = mx; |
| 339 | } |
| 340 | if ((f & f_prec) == 0) |
| 341 | prec = 6; |
| 342 | if ((f & f_prec)) |
| 343 | sz += prec + 16; |
| 344 | if ((f & f_wd) && wd + 1 > sz) |
| 345 | sz = wd + 1; |
| 346 | DENSURE(d, sz); |
| 347 | if (f & f_Long) |
| 348 | d->len += sprintf(d->buf + d->len, dd.buf, |
| 349 | va_arg(ap, long double)); |
| 350 | else |
| 351 | d->len += sprintf(d->buf + d->len, dd.buf, |
| 352 | va_arg(ap, double)); |
| 353 | goto formatted; |
| 354 | |
| 355 | case 'c': |
| 356 | DPUTC(&dd, *p); |
| 357 | DPUTZ(&dd); |
| 358 | if ((f & f_wd) && wd + 1> sz) |
| 359 | sz = wd + 1; |
| 360 | DENSURE(d, sz); |
| 361 | d->len += sprintf(d->buf + d->len, dd.buf, |
| 362 | va_arg(ap, unsigned char)); |
| 363 | goto formatted; |
| 364 | |
| 365 | case 's': { |
| 366 | const char *s = va_arg(ap, const char *); |
| 367 | sz = strlen(s); |
| 368 | DPUTC(&dd, *p); |
| 369 | DPUTZ(&dd); |
| 370 | if (f & f_prec) |
| 371 | sz = prec; |
| 372 | if ((f & f_wd) && wd > sz) |
| 373 | sz = wd; |
| 374 | DENSURE(d, sz + 1); |
| 375 | d->len += sprintf(d->buf + d->len, dd.buf, s); |
| 376 | goto formatted; |
| 377 | } |
| 378 | |
| 379 | case 'p': |
| 380 | DPUTC(&dd, *p); |
| 381 | DPUTZ(&dd); |
| 382 | if ((f & f_prec) && prec + 16 > sz) |
| 383 | sz = prec + 16; |
| 384 | if ((f & f_wd) && wd + 1> sz) |
| 385 | sz = wd + 1; |
| 386 | DENSURE(d, sz); |
| 387 | d->len += sprintf(d->buf + d->len, dd.buf, |
| 388 | va_arg(ap, const void *)); |
| 389 | goto formatted; |
| 390 | |
| 391 | case 'n': |
| 392 | if (f & f_long) |
| 393 | *va_arg(ap, long *) = (long)(d->len - n); |
| 394 | else if (f & f_short) |
| 395 | *va_arg(ap, short *) = (short)(d->len - n); |
| 396 | else |
| 397 | *va_arg(ap, int *) = (int)(d->len - n); |
| 398 | goto formatted; |
| 399 | |
| 400 | /* --- Other random stuff --- */ |
| 401 | |
| 402 | putch: |
| 403 | DPUTC(&dd, *p); |
| 404 | p++; |
| 405 | break; |
| 406 | } |
| 407 | } |
| 408 | |
| 409 | formatted: |
| 410 | dstr_destroy(&dd); |
| 411 | q = ++p; |
| 412 | } |
| 413 | |
| 414 | DPUTM(d, q, p - q); |
| 415 | finished: |
| 416 | DPUTZ(d); |
| 417 | return (d->len - n); |
| 418 | } |
| 419 | |
| 420 | /* --- @dstr_putf@ --- * |
| 421 | * |
| 422 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 423 | * @const char *p@ = pointer to @printf@-style format string |
| 424 | * @...@ = argument handle |
| 425 | * |
| 426 | * Returns: --- |
| 427 | * |
| 428 | * Use: Writes a piece of text to a dynamic string, doing @printf@- |
| 429 | * style substitutions as it goes. Intended to be robust if |
| 430 | * faced with malicious arguments, but not if the format string |
| 431 | * itself is malicious. |
| 432 | */ |
| 433 | |
| 434 | int dstr_putf(dstr *d, const char *p, ...) |
| 435 | { |
| 436 | int n; |
| 437 | va_list ap; |
| 438 | va_start(ap, p); |
| 439 | n = dstr_vputf(d, p, ap); |
| 440 | va_end(ap); |
| 441 | return (n); |
| 442 | } |
| 443 | |
| 444 | /* --- @dstr_putd@ --- * |
| 445 | * |
| 446 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 447 | * @const dstr *s@ = pointer to a dynamic string to append |
| 448 | * |
| 449 | * Returns: --- |
| 450 | * |
| 451 | * Use: Appends a dynamic string to a string. A trailing null |
| 452 | * byte is added, as for @dstr_putz@. |
| 453 | */ |
| 454 | |
| 455 | void dstr_putd(dstr *d, const dstr *s) |
| 456 | { |
| 457 | DPUTD(d, s); |
| 458 | } |
| 459 | |
| 460 | /* --- @dstr_putm@ --- * |
| 461 | * |
| 462 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 463 | * @const void *p@ = pointer to a block to append |
| 464 | * @size_t sz@ = size of the block |
| 465 | * |
| 466 | * Returns: Appends an arbitrary data block to a string. No trailing |
| 467 | * null is appended. |
| 468 | */ |
| 469 | |
| 470 | void dstr_putm(dstr *d, const void *p, size_t sz) |
| 471 | { |
| 472 | DPUTM(d, p, sz); |
| 473 | } |
| 474 | |
| 475 | /* --- @dstr_tidy@ --- * |
| 476 | * |
| 477 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 478 | * |
| 479 | * Returns: --- |
| 480 | * |
| 481 | * Use: Reduces the amount of memory used by a string. A trailing |
| 482 | * null byte is added, as for @dstr_putz@. |
| 483 | */ |
| 484 | |
| 485 | void dstr_tidy(dstr *d) |
| 486 | { |
| 487 | dstr_putz(d); |
| 488 | d->buf = xrealloc(d->buf, d->len + 1); |
| 489 | d->sz = d->len + 1; |
| 490 | } |
| 491 | |
| 492 | /* --- @dstr_putline@ --- * |
| 493 | * |
| 494 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 495 | * @FILE *fp@ = a stream to read from |
| 496 | * |
| 497 | * Returns: The number of characters read into the buffer, or @EOF@ if |
| 498 | * end-of-file was reached before any characters were read. |
| 499 | * |
| 500 | * Use: Appends the next line from the given input stream to the |
| 501 | * string. A trailing newline is not added; a trailing null |
| 502 | * byte is appended, as for @dstr_putz@. |
| 503 | */ |
| 504 | |
| 505 | int dstr_putline(dstr *d, FILE *fp) |
| 506 | { |
| 507 | size_t left = d->sz - d->len; |
| 508 | size_t off = d->len; |
| 509 | int rd = 0; |
| 510 | int ch; |
| 511 | |
| 512 | for (;;) { |
| 513 | |
| 514 | /* --- Make sure there's some buffer space --- */ |
| 515 | |
| 516 | if (!left) { |
| 517 | dstr_ensure(d, 1); |
| 518 | left = d->sz - off; |
| 519 | } |
| 520 | |
| 521 | /* --- Read the next byte --- */ |
| 522 | |
| 523 | ch = getc(fp); |
| 524 | |
| 525 | /* --- End-of-file when no characters read is special --- */ |
| 526 | |
| 527 | if (ch == EOF && !rd) |
| 528 | return (EOF); |
| 529 | |
| 530 | /* --- End-of-file or newline ends the loop --- */ |
| 531 | |
| 532 | if (ch == EOF || ch == '\n') { |
| 533 | d->buf[off] = 0; |
| 534 | d->len = off; |
| 535 | return rd; |
| 536 | } |
| 537 | |
| 538 | /* --- Append the character and continue --- */ |
| 539 | |
| 540 | d->buf[off++] = ch; |
| 541 | left--; rd++; |
| 542 | } |
| 543 | } |
| 544 | |
| 545 | /* --- @dstr_write@ --- * |
| 546 | * |
| 547 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 548 | * @FILE *fp@ = a stream to write on |
| 549 | * |
| 550 | * Returns: The number of bytes written (as for @fwrite@). |
| 551 | * |
| 552 | * Use: Writes a dynamic string to a file. |
| 553 | */ |
| 554 | |
| 555 | size_t dstr_write(dstr *d, FILE *fp) |
| 556 | { |
| 557 | return (fwrite(d->buf, 1, d->len, fp)); |
| 558 | } |
| 559 | |
| 560 | /*----- That's all, folks -------------------------------------------------*/ |