strio.c revision 95154
1/* 2 * Copyright (c) 2000-2002 Sendmail, Inc. and its suppliers. 3 * All rights reserved. 4 * Copyright (c) 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Chris Torek. 9 * 10 * By using this file, you agree to the terms and conditions set 11 * forth in the LICENSE file which can be found at the top level of 12 * the sendmail distribution. 13 */ 14 15#include <sm/gen.h> 16SM_IDSTR(id, "@(#)$Id: strio.c,v 1.1.1.2 2002/04/10 03:04:56 gshapiro Exp $") 17#include <stdlib.h> 18#include <unistd.h> 19#include <fcntl.h> 20#include <string.h> 21#include <errno.h> 22#include <sm/rpool.h> 23#include <sm/io.h> 24#include <sm/heap.h> 25#include <sm/conf.h> 26#include "local.h" 27 28/* 29** Cookie structure for the "strio" file type 30*/ 31 32struct sm_str_obj 33{ 34 char *strio_base; 35 char *strio_end; 36 size_t strio_size; 37 size_t strio_offset; 38 int strio_flags; 39 const void *strio_rpool; 40}; 41 42typedef struct sm_str_obj SM_STR_OBJ_T; 43 44/* 45** SM_STRGROW -- increase storage space for string 46** 47** Parameters: 48** s -- current cookie 49** size -- new storage size request 50** 51** Returns: 52** true iff successful. 53*/ 54 55static bool sm_strgrow __P((SM_STR_OBJ_T *, size_t)); 56 57static bool 58sm_strgrow(s, size) 59 SM_STR_OBJ_T *s; 60 size_t size; 61{ 62 register void *p; 63 64 if (s->strio_size >= size) 65 return true; 66 p = sm_realloc(s->strio_base, size); 67 if (p == NULL) 68 return false; 69 s->strio_base = p; 70 s->strio_end = s->strio_base + size; 71 s->strio_size = size; 72 return true; 73} 74 75/* 76** SM_STRREAD -- read a portion of the string 77** 78** Parameters: 79** fp -- the file pointer 80** buf -- location to place read data 81** n -- number of bytes to read 82** 83** Returns: 84** Failure: -1 and sets errno 85** Success: >=0, number of bytes read 86*/ 87 88ssize_t 89sm_strread(fp, buf, n) 90 SM_FILE_T *fp; 91 char *buf; 92 size_t n; 93{ 94 register SM_STR_OBJ_T *s = fp->f_cookie; 95 int len; 96 97 if (!(s->strio_flags & SMRD) && !(s->strio_flags & SMRW)) 98 { 99 errno = EBADF; 100 return -1; 101 } 102 len = SM_MIN(s->strio_size - s->strio_offset, n); 103 (void) memmove(buf, s->strio_base + s->strio_offset, len); 104 s->strio_offset += len; 105 return len; 106} 107 108/* 109** SM_STRWRITE -- write a portion of the string 110** 111** Parameters: 112** fp -- the file pointer 113** buf -- location of data for writing 114** n -- number of bytes to write 115** 116** Returns: 117** Failure: -1 and sets errno 118** Success: >=0, number of bytes written 119*/ 120 121ssize_t 122sm_strwrite(fp, buf, n) 123 SM_FILE_T *fp; 124 char const *buf; 125 size_t n; 126{ 127 register SM_STR_OBJ_T *s = fp->f_cookie; 128 129 if (!(s->strio_flags & SMWR) && !(s->strio_flags & SMRW)) 130 { 131 errno = EBADF; 132 return -1; 133 } 134 if (n + s->strio_offset > s->strio_size) 135 { 136 if (!sm_strgrow(s, n + s->strio_offset)) 137 return 0; 138 } 139 (void) memmove(s->strio_base + s->strio_offset, buf, n); 140 s->strio_offset += n; 141 return n; 142} 143 144/* 145** SM_STRSEEK -- position the offset pointer for the string 146** 147** Only SM_IO_SEEK_SET, SM_IO_SEEK_CUR and SM_IO_SEEK_END are valid 148** values for whence. 149** 150** Parameters: 151** fp -- the file pointer 152** offset -- number of bytes offset from "base" 153** whence -- determines "base" for 'offset' 154** 155** Returns: 156** Failure: -1 and sets errno 157** Success: >=0, number of bytes read 158*/ 159 160off_t 161sm_strseek(fp, offset, whence) 162 SM_FILE_T *fp; 163 off_t offset; 164 int whence; 165{ 166 register off_t ret; 167 register SM_STR_OBJ_T *s = fp->f_cookie; 168 169reseek: 170 switch (whence) 171 { 172 case SM_IO_SEEK_SET: 173 ret = offset; 174 break; 175 case SM_IO_SEEK_CUR: 176 ret = s->strio_offset + offset; 177 break; 178 case SM_IO_SEEK_END: 179 ret = s->strio_size; 180 break; 181 default: 182 errno = EINVAL; 183 return -1; 184 } 185 if (ret < 0 || ret > (off_t)(size_t)(-1)) /* XXX ugly */ 186 return -1; 187 if ((size_t) ret > s->strio_size) 188 { 189 if (sm_strgrow(s, (size_t)ret)) 190 goto reseek; 191 192 /* errno set by sm_strgrow */ 193 return -1; 194 } 195 s->strio_offset = (size_t) ret; 196 return ret; 197} 198 199/* 200** SM_STROPEN -- open a string file type 201** 202** Parameters: 203** fp -- file pointer open to be associated with 204** info -- initial contents (NULL for none) 205** flags -- flags for methods of access (was mode) 206** rpool -- resource pool to use memory from (if applicable) 207** 208** Results: 209** Success: 0 (zero) 210** Failure: -1 and sets errno 211*/ 212 213int 214sm_stropen(fp, info, flags, rpool) 215 SM_FILE_T *fp; 216 const void *info; 217 int flags; 218 const void *rpool; 219{ 220 register SM_STR_OBJ_T *s; 221 222#if SM_RPOOL 223 s = sm_rpool_malloc_x(rpool, sizeof(SM_STR_OBJ_T)); 224#else /* SM_RPOOL */ 225 s = sm_malloc(sizeof(SM_STR_OBJ_T)); 226 if (s == NULL) 227 return -1; 228#endif /* SM_RPOOL */ 229 230 fp->f_cookie = s; 231 s->strio_rpool = rpool; 232 s->strio_offset = 0; 233 s->strio_size = 0; 234 s->strio_base = NULL; 235 s->strio_end = 0; 236 237 switch (flags) 238 { 239 case SM_IO_RDWR: 240 s->strio_flags = SMRW; 241 break; 242 case SM_IO_RDONLY: 243 s->strio_flags = SMRD; 244 break; 245 case SM_IO_WRONLY: 246 s->strio_flags = SMWR; 247 break; 248 case SM_IO_APPEND: 249 if (s->strio_rpool == NULL) 250 sm_free(s); 251 errno = EINVAL; 252 return -1; 253 default: 254 if (s->strio_rpool == NULL) 255 sm_free(s); 256 errno = EINVAL; 257 return -1; 258 } 259 260 if (info != NULL) 261 { 262 s->strio_base = sm_strdup_x(info); 263 if (s->strio_base == NULL) 264 { 265 int save_errno = errno; 266 267 if (s->strio_rpool == NULL) 268 sm_free(s); 269 errno = save_errno; 270 return -1; 271 } 272 s->strio_size = strlen(info); 273 s->strio_end = s->strio_base + s->strio_size; 274 } 275 return 0; 276} 277 278/* 279** SM_STRCLOSE -- close the string file type and free resources 280** 281** Parameters: 282** fp -- file pointer 283** 284** Results: 285** Success: 0 (zero) 286*/ 287 288int 289sm_strclose(fp) 290 SM_FILE_T *fp; 291{ 292 SM_STR_OBJ_T *s = fp->f_cookie; 293 294#if !SM_RPOOL 295 sm_free(s->strio_base); 296 s->strio_base = NULL; 297#endif /* !SM_RPOOL */ 298 return 0; 299} 300 301/* 302** SM_STRSETMODE -- set mode info for the file 303** 304** Note: changing the mode can be a safe way to have the "parent" 305** set up a string that the "child" is not to modify 306** 307** Parameters: 308** fp -- the file pointer 309** mode -- location of new mode to set 310** 311** Results: 312** Success: 0 (zero) 313** Failure: -1 and sets errno 314*/ 315 316int 317sm_strsetmode(fp, mode) 318 SM_FILE_T *fp; 319 const int *mode; 320{ 321 register SM_STR_OBJ_T *s = fp->f_cookie; 322 int flags; 323 324 switch (*mode) 325 { 326 case SM_IO_RDWR: 327 flags = SMRW; 328 break; 329 case SM_IO_RDONLY: 330 flags = SMRD; 331 break; 332 case SM_IO_WRONLY: 333 flags = SMWR; 334 break; 335 case SM_IO_APPEND: 336 errno = EINVAL; 337 return -1; 338 default: 339 errno = EINVAL; 340 return -1; 341 } 342 s->strio_flags &= ~SMMODEMASK; 343 s->strio_flags |= flags; 344 return 0; 345} 346 347/* 348** SM_STRGETMODE -- get mode info for the file 349** 350** Parameters: 351** fp -- the file pointer 352** mode -- location to store current mode 353** 354** Results: 355** Success: 0 (zero) 356** Failure: -1 and sets errno 357*/ 358 359int 360sm_strgetmode(fp, mode) 361 SM_FILE_T *fp; 362 int *mode; 363{ 364 register SM_STR_OBJ_T *s = fp->f_cookie; 365 366 switch (s->strio_flags & SMMODEMASK) 367 { 368 case SMRW: 369 *mode = SM_IO_RDWR; 370 break; 371 case SMRD: 372 *mode = SM_IO_RDONLY; 373 break; 374 case SMWR: 375 *mode = SM_IO_WRONLY; 376 break; 377 default: 378 errno = EINVAL; 379 return -1; 380 } 381 return 0; 382} 383 384/* 385** SM_STRSETINFO -- set info for the file 386** 387** Currently only SM_IO_WHAT_MODE is supported for 'what'. 388** 389** Parameters: 390** fp -- the file pointer 391** what -- type of information to set 392** valp -- location to data for doing set 393** 394** Results: 395** Failure: -1 and sets errno 396** Success: sm_strsetmode() return [0 (zero)] 397*/ 398 399int 400sm_strsetinfo(fp, what, valp) 401 SM_FILE_T *fp; 402 int what; 403 void *valp; 404{ 405 switch(what) 406 { 407 case SM_IO_WHAT_MODE: 408 return sm_strsetmode(fp, (int *) valp); 409 default: 410 errno = EINVAL; 411 return -1; 412 } 413} 414 415/* 416** SM_STRGETINFO -- get info for the file 417** 418** Currently only SM_IO_WHAT_MODE is supported for 'what'. 419** 420** Parameters: 421** fp -- the file pointer 422** what -- type of information requested 423** valp -- location to return information in 424** 425** Results: 426** Failure: -1 and sets errno 427** Success: sm_strgetmode() return [0 (zero)] 428*/ 429 430int 431sm_strgetinfo(fp, what, valp) 432 SM_FILE_T *fp; 433 int what; 434 void *valp; 435{ 436 switch(what) 437 { 438 case SM_IO_WHAT_MODE: 439 return sm_strgetmode(fp, (int *) valp); 440 default: 441 errno = EINVAL; 442 return -1; 443 } 444} 445 446/* 447** SM_STRIO_INIT -- initializes a write-only string type 448** 449** Original comments below. This function does not appear to be used anywhere. 450** The same functionality can be done by changing the mode of the file. 451** ------------ 452** sm_strio_init initializes an SM_FILE_T structure as a write-only file 453** that writes into the specified buffer: 454** - Use sm_io_putc, sm_io_fprintf, etc, to write into the buffer. 455** Attempts to write more than size-1 characters into the buffer will fail 456** silently (no error is reported). 457** - Use sm_io_fflush to nul terminate the string in the buffer 458** (the write pointer is not advanced). 459** No memory is allocated either by sm_strio_init or by sm_io_{putc,write} etc. 460** 461** Parameters: 462** fp -- file pointer 463** buf -- memory location for stored data 464** size -- size of 'buf' 465** 466** Results: 467** none. 468*/ 469 470void 471sm_strio_init(fp, buf, size) 472 SM_FILE_T *fp; 473 char *buf; 474 size_t size; 475{ 476 fp->sm_magic = SmFileMagic; 477 fp->f_flags = SMWR | SMSTR; 478 fp->f_file = -1; 479 fp->f_bf.smb_base = fp->f_p = (unsigned char *) buf; 480 fp->f_bf.smb_size = fp->f_w = (size ? size - 1 : 0); 481 fp->f_lbfsize = 0; 482 fp->f_r = 0; 483 fp->f_read = NULL; 484 fp->f_seek = NULL; 485 fp->f_getinfo = NULL; 486 fp->f_setinfo = NULL; 487} 488