1 /*- 2 * Copyright (c) 2000 Poul-Henning Kamp and Dag-Erling Co�dan Sm�rgrav 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 */ 30 31 #include <sys/param.h> 32 33 #ifdef _KERNEL 34 #include <sys/ctype.h> 35 #include <sys/kernel.h> 36 #include <sys/malloc.h> 37 #include <sys/systm.h> 38 #include <sys/uio.h> 39 #include <machine/stdarg.h> 40 #else /* _KERNEL */ 41 #include <ctype.h> 42 #include <stdarg.h> 43 #include <stdlib.h> 44 #endif /* _KERNEL */ 45 46 #include <sys/sbuf.h> 47 48 #ifdef _KERNEL 49 MALLOC_DEFINE(M_SBUF, "sbuf", "string buffers"); 50 #define SBMALLOC(size) malloc(size, M_SBUF, M_WAITOK) 51 #define SBFREE(buf) free(buf, M_SBUF) 52 #else /* _KERNEL */ 53 #define KASSERT(e, m) 54 #define SBMALLOC(size) malloc(size) 55 #define SBFREE(buf) free(buf) 56 #define min(x,y) MIN(x,y) 57 #endif /* _KERNEL */ 58 59 /* 60 * Predicates 61 */ 62 #define SBUF_ISDYNAMIC(s) ((s)->s_flags & SBUF_DYNAMIC) 63 #define SBUF_ISDYNSTRUCT(s) ((s)->s_flags & SBUF_DYNSTRUCT) 64 #define SBUF_ISFINISHED(s) ((s)->s_flags & SBUF_FINISHED) 65 #define SBUF_HASOVERFLOWED(s) ((s)->s_flags & SBUF_OVERFLOWED) 66 #define SBUF_HASROOM(s) ((s)->s_len < (s)->s_size - 1) 67 68 /* 69 * Set / clear flags 70 */ 71 #define SBUF_SETFLAG(s, f) do { (s)->s_flags |= (f); } while (0) 72 #define SBUF_CLEARFLAG(s, f) do { (s)->s_flags &= ~(f); } while (0) 73 74 /* 75 * Debugging support 76 */ 77 #if defined(_KERNEL) && defined(INVARIANTS) 78 static void 79 _assert_sbuf_integrity(char *fun, struct sbuf *s) 80 { 81 KASSERT(s != NULL, 82 ("%s called with a NULL sbuf pointer", fun)); 83 KASSERT(s->s_buf != NULL, 84 ("%s called with unitialized or corrupt sbuf", fun)); 85 KASSERT(s->s_len < s->s_size, 86 ("wrote past end of sbuf (%d >= %d)", s->s_len, s->s_size)); 87 } 88 89 static void 90 _assert_sbuf_state(char *fun, struct sbuf *s, int state) 91 { 92 KASSERT((s->s_flags & SBUF_FINISHED) == state, 93 ("%s called with %sfinished or corrupt sbuf", fun, 94 (state ? "un" : ""))); 95 } 96 #define assert_sbuf_integrity(s) _assert_sbuf_integrity(__func__, (s)) 97 #define assert_sbuf_state(s, i) _assert_sbuf_state(__func__, (s), (i)) 98 #else /* _KERNEL && INVARIANTS */ 99 #define assert_sbuf_integrity(s) do { } while (0) 100 #define assert_sbuf_state(s, i) do { } while (0) 101 #endif /* _KERNEL && INVARIANTS */ 102 103 /* 104 * Initialize an sbuf. 105 * If buf is non-NULL, it points to a static or already-allocated string 106 * big enough to hold at least length characters. 107 */ 108 struct sbuf * 109 sbuf_new(struct sbuf *s, char *buf, int length, int flags) 110 { 111 KASSERT(length >= 0, 112 ("attempt to create an sbuf of negative length (%d)", length)); 113 KASSERT(flags == 0, 114 ("%s called with non-zero flags", __func__)); 115 116 if (s == NULL) { 117 s = (struct sbuf *)SBMALLOC(sizeof *s); 118 if (s == NULL) 119 return (NULL); 120 bzero(s, sizeof *s); 121 SBUF_SETFLAG(s, SBUF_DYNSTRUCT); 122 } else { 123 bzero(s, sizeof *s); 124 } 125 s->s_size = length; 126 if (buf) { 127 s->s_buf = buf; 128 return (s); 129 } 130 s->s_buf = (char *)SBMALLOC(s->s_size); 131 if (s->s_buf == NULL) { 132 if (SBUF_ISDYNSTRUCT(s)) 133 SBFREE(s); 134 return (NULL); 135 } 136 SBUF_SETFLAG(s, SBUF_DYNAMIC); 137 return (s); 138 } 139 140 #ifdef _KERNEL 141 /* 142 * Create an sbuf with uio data 143 */ 144 struct sbuf * 145 sbuf_uionew(struct sbuf *s, struct uio *uio, int *error) 146 { 147 KASSERT(uio != NULL, 148 ("%s called with NULL uio pointer", __func__)); 149 KASSERT(error != NULL, 150 ("%s called with NULL error pointer", __func__)); 151 152 s = sbuf_new(s, NULL, uio->uio_resid + 1, 0); 153 if (s == NULL) { 154 *error = ENOMEM; 155 return (NULL); 156 } 157 *error = uiomove(s->s_buf, uio->uio_resid, uio); 158 if (*error != 0) { 159 sbuf_delete(s); 160 return (NULL); 161 } 162 s->s_len = s->s_size - 1; 163 *error = 0; 164 return (s); 165 } 166 #endif 167 168 /* 169 * Clear an sbuf and reset its position 170 */ 171 void 172 sbuf_clear(struct sbuf *s) 173 { 174 assert_sbuf_integrity(s); 175 /* don't care if it's finished or not */ 176 177 SBUF_CLEARFLAG(s, SBUF_FINISHED); 178 SBUF_CLEARFLAG(s, SBUF_OVERFLOWED); 179 s->s_len = 0; 180 } 181 182 /* 183 * Set the sbuf's position to an arbitrary value 184 */ 185 int 186 sbuf_setpos(struct sbuf *s, int pos) 187 { 188 assert_sbuf_integrity(s); 189 assert_sbuf_state(s, 0); 190 191 KASSERT(pos >= 0, 192 ("attempt to seek to a negative position (%d)", pos)); 193 KASSERT(pos < s->s_size, 194 ("attempt to seek past end of sbuf (%d >= %d)", pos, s->s_size)); 195 196 if (pos < 0 || pos > s->s_len) 197 return (-1); 198 s->s_len = pos; 199 return (0); 200 } 201 202 /* 203 * Append a byte string to an sbuf. 204 */ 205 int 206 sbuf_bcat(struct sbuf *s, const char *str, size_t len) 207 { 208 assert_sbuf_integrity(s); 209 assert_sbuf_state(s, 0); 210 211 if (SBUF_HASOVERFLOWED(s)) 212 return (-1); 213 214 while (len-- && SBUF_HASROOM(s)) 215 s->s_buf[s->s_len++] = *str++; 216 if (len) { 217 SBUF_SETFLAG(s, SBUF_OVERFLOWED); 218 return (-1); 219 } 220 return (0); 221 } 222 223 #ifdef _KERNEL 224 /* 225 * Copy a byte string from userland into an sbuf. 226 */ 227 int 228 sbuf_bcopyin(struct sbuf *s, const void *uaddr, size_t len) 229 { 230 assert_sbuf_integrity(s); 231 assert_sbuf_state(s, 0); 232 233 if (SBUF_HASOVERFLOWED(s)) 234 return (-1); 235 236 if (len == 0) 237 return (0); 238 if (len > (s->s_size - s->s_len - 1)) 239 len = s->s_size - s->s_len - 1; 240 if (copyin(uaddr, s->s_buf + s->s_len, len) != 0) 241 return (-1); 242 s->s_len += len; 243 244 return (0); 245 } 246 #endif 247 248 /* 249 * Copy a byte string into an sbuf. 250 */ 251 int 252 sbuf_bcpy(struct sbuf *s, const char *str, size_t len) 253 { 254 assert_sbuf_integrity(s); 255 assert_sbuf_state(s, 0); 256 257 sbuf_clear(s); 258 return (sbuf_bcat(s, str, len)); 259 } 260 261 /* 262 * Append a string to an sbuf. 263 */ 264 int 265 sbuf_cat(struct sbuf *s, const char *str) 266 { 267 assert_sbuf_integrity(s); 268 assert_sbuf_state(s, 0); 269 270 if (SBUF_HASOVERFLOWED(s)) 271 return (-1); 272 273 while (*str && SBUF_HASROOM(s)) 274 s->s_buf[s->s_len++] = *str++; 275 if (*str) { 276 SBUF_SETFLAG(s, SBUF_OVERFLOWED); 277 return (-1); 278 } 279 return (0); 280 } 281 282 #ifdef _KERNEL 283 /* 284 * Copy a string from userland into an sbuf. 285 */ 286 int 287 sbuf_copyin(struct sbuf *s, const void *uaddr, size_t len) 288 { 289 size_t done; 290 291 assert_sbuf_integrity(s); 292 assert_sbuf_state(s, 0); 293 294 if (SBUF_HASOVERFLOWED(s)) 295 return (-1); 296 297 if (len == 0 || len > (s->s_size - s->s_len - 1)) 298 len = s->s_size - s->s_len - 1; 299 switch (copyinstr(uaddr, s->s_buf + s->s_len, len + 1, &done)) { 300 case ENAMETOOLONG: 301 SBUF_SETFLAG(s, SBUF_OVERFLOWED); 302 /* fall through */ 303 case 0: 304 s->s_len += done - 1; 305 break; 306 default: 307 return (-1); /* XXX */ 308 } 309 310 return (0); 311 } 312 #endif 313 314 /* 315 * Copy a string into an sbuf. 316 */ 317 int 318 sbuf_cpy(struct sbuf *s, const char *str) 319 { 320 assert_sbuf_integrity(s); 321 assert_sbuf_state(s, 0); 322 323 sbuf_clear(s); 324 return (sbuf_cat(s, str)); 325 } 326 327 /* 328 * Format the given arguments and append the resulting string to an sbuf. 329 */ 330 int 331 sbuf_printf(struct sbuf *s, const char *fmt, ...) 332 { 333 va_list ap; 334 int len; 335 336 assert_sbuf_integrity(s); 337 assert_sbuf_state(s, 0); 338 339 KASSERT(fmt != NULL, 340 ("%s called with a NULL format string", __func__)); 341 342 if (SBUF_HASOVERFLOWED(s)) 343 return (-1); 344 345 va_start(ap, fmt); 346 len = vsnprintf(&s->s_buf[s->s_len], s->s_size - s->s_len, fmt, ap); 347 va_end(ap); 348 349 /* 350 * s->s_len is the length of the string, without the terminating nul. 351 * When updating s->s_len, we must subtract 1 from the length that 352 * we passed into vsnprintf() because that length includes the 353 * terminating nul. 354 * 355 * vsnprintf() returns the amount that would have been copied, 356 * given sufficient space, hence the min() calculation below. 357 */ 358 s->s_len += min(len, s->s_size - s->s_len - 1); 359 if (!SBUF_HASROOM(s)) 360 SBUF_SETFLAG(s, SBUF_OVERFLOWED); 361 362 KASSERT(s->s_len < s->s_size, 363 ("wrote past end of sbuf (%d >= %d)", s->s_len, s->s_size)); 364 365 if (SBUF_HASOVERFLOWED(s)) 366 return (-1); 367 return (0); 368 } 369 370 /* 371 * Append a character to an sbuf. 372 */ 373 int 374 sbuf_putc(struct sbuf *s, int c) 375 { 376 assert_sbuf_integrity(s); 377 assert_sbuf_state(s, 0); 378 379 if (SBUF_HASOVERFLOWED(s)) 380 return (-1); 381 382 if (!SBUF_HASROOM(s)) { 383 SBUF_SETFLAG(s, SBUF_OVERFLOWED); 384 return (-1); 385 } 386 if (c != '\0') 387 s->s_buf[s->s_len++] = c; 388 return (0); 389 } 390 391 /* 392 * Trim whitespace characters from an sbuf. 393 */ 394 int 395 sbuf_trim(struct sbuf *s) 396 { 397 assert_sbuf_integrity(s); 398 assert_sbuf_state(s, 0); 399 400 if (SBUF_HASOVERFLOWED(s)) 401 return (-1); 402 403 while (s->s_len && isspace(s->s_buf[s->s_len-1])) 404 --s->s_len; 405 406 return (0); 407 } 408 409 /* 410 * Check if an sbuf overflowed 411 */ 412 int 413 sbuf_overflowed(struct sbuf *s) 414 { 415 return SBUF_HASOVERFLOWED(s); 416 } 417 418 /* 419 * Finish off an sbuf. 420 */ 421 void 422 sbuf_finish(struct sbuf *s) 423 { 424 assert_sbuf_integrity(s); 425 assert_sbuf_state(s, 0); 426 427 s->s_buf[s->s_len] = '\0'; 428 SBUF_CLEARFLAG(s, SBUF_OVERFLOWED); 429 SBUF_SETFLAG(s, SBUF_FINISHED); 430 } 431 432 /* 433 * Return a pointer to the sbuf data. 434 */ 435 char * 436 sbuf_data(struct sbuf *s) 437 { 438 assert_sbuf_integrity(s); 439 assert_sbuf_state(s, SBUF_FINISHED); 440 441 return s->s_buf; 442 } 443 444 /* 445 * Return the length of the sbuf data. 446 */ 447 int 448 sbuf_len(struct sbuf *s) 449 { 450 assert_sbuf_integrity(s); 451 /* don't care if it's finished or not */ 452 453 if (SBUF_HASOVERFLOWED(s)) 454 return (-1); 455 return s->s_len; 456 } 457 458 /* 459 * Clear an sbuf, free its buffer if necessary. 460 */ 461 void 462 sbuf_delete(struct sbuf *s) 463 { 464 assert_sbuf_integrity(s); 465 /* don't care if it's finished or not */ 466 467 if (SBUF_ISDYNAMIC(s)) 468 SBFREE(s->s_buf); 469 bzero(s, sizeof *s); 470 if (SBUF_ISDYNSTRUCT(s)) 471 SBFREE(s); 472 } 473