| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Handle dynamically growing strings |
| 4 | * |
| 5 | * (c) 1998 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of the mLib utilities library. |
| 11 | * |
| 12 | * mLib is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU Library General Public License as |
| 14 | * published by the Free Software Foundation; either version 2 of the |
| 15 | * License, or (at your option) any later version. |
| 16 | * |
| 17 | * mLib is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU Library General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU Library General Public |
| 23 | * License along with mLib; if not, write to the Free |
| 24 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 25 | * MA 02111-1307, USA. |
| 26 | */ |
| 27 | |
| 28 | #ifndef MLIB_DSTR_H |
| 29 | #define MLIB_DSTR_H |
| 30 | |
| 31 | #ifdef __cplusplus |
| 32 | extern "C" { |
| 33 | #endif |
| 34 | |
| 35 | /*----- Rationale ---------------------------------------------------------* |
| 36 | * |
| 37 | * This file declares what is hopefully a fairly useful collection of |
| 38 | * primitive string handling functions. The idea is that the strings |
| 39 | * allocate memory for themselves as required. The @dstr@ routines don't |
| 40 | * assume any sort of terminator character, so arbitrary binary data can |
| 41 | * be stored in a dynamic string. With luck, this should put a stop to |
| 42 | * any buffer overflow problems. |
| 43 | */ |
| 44 | |
| 45 | /*----- Header files ------------------------------------------------------*/ |
| 46 | |
| 47 | #include <stdarg.h> |
| 48 | #include <stdio.h> |
| 49 | #include <stdlib.h> |
| 50 | |
| 51 | #ifndef MLIB_ALLOC_H |
| 52 | # include "alloc.h" |
| 53 | #endif |
| 54 | |
| 55 | #ifndef MLIB_ARENA_H |
| 56 | # include "arena.h" |
| 57 | #endif |
| 58 | |
| 59 | #ifndef MLIB_MACROS_H |
| 60 | # include "macros.h" |
| 61 | #endif |
| 62 | |
| 63 | /*----- Data structures ---------------------------------------------------*/ |
| 64 | |
| 65 | typedef struct dstr { |
| 66 | char *buf; /* Pointer to string buffer */ |
| 67 | size_t sz; /* Size of the buffer */ |
| 68 | size_t len; /* Length of the string */ |
| 69 | arena *a; /* Pointer to arena */ |
| 70 | } dstr; |
| 71 | |
| 72 | #define DSTR_INIT { 0, 0, 0, &arena_stdlib } /* How to initialize one */ |
| 73 | |
| 74 | /*----- Functions provided ------------------------------------------------*/ |
| 75 | |
| 76 | /* --- @dstr_create@ --- * |
| 77 | * |
| 78 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 79 | * |
| 80 | * Returns: --- |
| 81 | * |
| 82 | * Use: Initializes a dynamic string. |
| 83 | */ |
| 84 | |
| 85 | extern void dstr_create(dstr */*d*/); |
| 86 | |
| 87 | #define DCREATE(d) do { \ |
| 88 | dstr *_dd = (d); \ |
| 89 | _dd->buf = 0; \ |
| 90 | _dd->sz = 0; \ |
| 91 | _dd->len = 0; \ |
| 92 | _dd->a = &arena_stdlib; \ |
| 93 | } while (0) |
| 94 | |
| 95 | /* --- @dstr_destroy@ --- * |
| 96 | * |
| 97 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 98 | * |
| 99 | * Returns: --- |
| 100 | * |
| 101 | * Use: Reclaims the space used by a dynamic string. |
| 102 | */ |
| 103 | |
| 104 | extern void dstr_destroy(dstr */*d*/); |
| 105 | |
| 106 | #define DDESTROY(d) do { \ |
| 107 | dstr *_d = (d); \ |
| 108 | if (_d->buf) \ |
| 109 | x_free(_d->a, _d->buf); \ |
| 110 | DCREATE(_d); \ |
| 111 | } while (0) |
| 112 | |
| 113 | /* --- @dstr_reset@ --- * |
| 114 | * |
| 115 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 116 | * |
| 117 | * Returns: --- |
| 118 | * |
| 119 | * Use: Resets a string so that new data gets put at the beginning. |
| 120 | */ |
| 121 | |
| 122 | extern void dstr_reset(dstr */*d*/); |
| 123 | |
| 124 | #define DRESET(d) ((d)->len = 0) |
| 125 | |
| 126 | /* --- @dstr_ensure@ --- * |
| 127 | * |
| 128 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 129 | * @size_t sz@ = amount of free space to ensure |
| 130 | * |
| 131 | * Returns: --- |
| 132 | * |
| 133 | * Use: Ensures that at least @sz@ bytes are available in the |
| 134 | * given string. |
| 135 | */ |
| 136 | |
| 137 | extern void dstr_ensure(dstr */*d*/, size_t /*sz*/); |
| 138 | |
| 139 | #define DENSURE(d, rq) do { \ |
| 140 | dstr *_dd = (d); \ |
| 141 | size_t _rq = (rq); \ |
| 142 | if (_dd->len + _rq > _dd->sz) dstr_ensure(_dd, _rq); \ |
| 143 | } while (0) |
| 144 | |
| 145 | /* --- @dstr_putc@ --- * |
| 146 | * |
| 147 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 148 | * @int ch@ = character to append |
| 149 | * |
| 150 | * Returns: --- |
| 151 | * |
| 152 | * Use: Appends a character to a string. |
| 153 | */ |
| 154 | |
| 155 | extern void dstr_putc(dstr */*d*/, int /*ch*/); |
| 156 | |
| 157 | #define DPUTC(d, ch) do { \ |
| 158 | dstr *_d = (d); \ |
| 159 | DENSURE(_d, 1); \ |
| 160 | *((unsigned char *)_d->buf + _d->len++) = (ch); \ |
| 161 | } while (0) |
| 162 | |
| 163 | /* --- @dstr_putz@ --- * |
| 164 | * |
| 165 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 166 | * |
| 167 | * Returns: --- |
| 168 | * |
| 169 | * Use: Appends a null byte to a string. The null byte does not |
| 170 | * contribute to the string's length, and will be overwritten |
| 171 | * by subsequent `put' operations. |
| 172 | */ |
| 173 | |
| 174 | extern void dstr_putz(dstr */*d*/); |
| 175 | |
| 176 | #define DPUTZ(d) do { \ |
| 177 | dstr *_d = (d); \ |
| 178 | DENSURE(_d, 1); \ |
| 179 | _d->buf[_d->len] = 0; \ |
| 180 | } while (0) |
| 181 | |
| 182 | /* --- @dstr_puts@ --- * |
| 183 | * |
| 184 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 185 | * @const char *s@ = pointer to string to append |
| 186 | * |
| 187 | * Returns: --- |
| 188 | * |
| 189 | * Use: Appends a character string to a string. A trailing null |
| 190 | * byte is added, as for @dstr_putz@. |
| 191 | */ |
| 192 | |
| 193 | extern void dstr_puts(dstr */*d*/, const char */*s*/); |
| 194 | |
| 195 | #define DPUTS(d, s) do { \ |
| 196 | dstr *_d = (d); \ |
| 197 | const char *_s = (s); \ |
| 198 | size_t _sz = strlen(_s); \ |
| 199 | DENSURE(_d, _sz + 1); \ |
| 200 | memcpy(_d->buf + _d->len, _s, _sz + 1); \ |
| 201 | _d->len += _sz; \ |
| 202 | } while (0) |
| 203 | |
| 204 | /* --- @dstr_vputf@ --- * |
| 205 | * |
| 206 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 207 | * @const char *p@ = pointer to @printf@-style format string |
| 208 | * @va_list *ap@ = argument handle |
| 209 | * |
| 210 | * Returns: The number of characters written to the string. |
| 211 | * |
| 212 | * Use: As for @dstr_putf@, but may be used as a back-end to user- |
| 213 | * supplied functions with @printf@-style interfaces. |
| 214 | */ |
| 215 | |
| 216 | extern int dstr_vputf(dstr */*d*/, const char */*p*/, va_list */*ap*/); |
| 217 | |
| 218 | /* --- @dstr_putf@ --- * |
| 219 | * |
| 220 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 221 | * @const char *p@ = pointer to @printf@-style format string |
| 222 | * @...@ = argument handle |
| 223 | * |
| 224 | * Returns: The number of characters written to the string. |
| 225 | * |
| 226 | * Use: Writes a piece of text to a dynamic string, doing @printf@- |
| 227 | * style substitutions as it goes. Intended to be robust if |
| 228 | * faced with malicious arguments, but not if the format string |
| 229 | * itself is malicious. |
| 230 | */ |
| 231 | |
| 232 | extern int PRINTF_LIKE(2, 3) |
| 233 | dstr_putf(dstr */*d*/, const char */*p*/, ...); |
| 234 | |
| 235 | /* --- @dstr_putd@ --- * |
| 236 | * |
| 237 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 238 | * @const dstr *s@ = pointer to a dynamic string to append |
| 239 | * |
| 240 | * Returns: --- |
| 241 | * |
| 242 | * Use: Appends a dynamic string to a string. A trailing null |
| 243 | * byte is added, as for @dstr_putz@. |
| 244 | */ |
| 245 | |
| 246 | extern void dstr_putd(dstr */*d*/, const dstr */*s*/); |
| 247 | |
| 248 | #define DPUTD(d, s) do { \ |
| 249 | dstr *_d = (d); \ |
| 250 | const dstr *_s = (s); \ |
| 251 | DENSURE(_d, _s->len + 1); \ |
| 252 | memcpy(_d->buf + _d->len, _s->buf, _s->len); \ |
| 253 | _d->len += _s->len; \ |
| 254 | _d->buf[_d->len] = 0; \ |
| 255 | } while (0) |
| 256 | |
| 257 | /* --- @dstr_putm@ --- * |
| 258 | * |
| 259 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 260 | * @const void *p@ = pointer to a block to append |
| 261 | * @size_t sz@ = size of the block |
| 262 | * |
| 263 | * Returns: Appends an arbitrary data block to a string. No trailing |
| 264 | * null is appended. |
| 265 | */ |
| 266 | |
| 267 | extern void dstr_putm(dstr */*d*/, const void */*p*/, size_t /*sz*/); |
| 268 | |
| 269 | #define DPUTM(d, p, sz) do { \ |
| 270 | dstr *_d = (d); \ |
| 271 | size_t _sz = (sz); \ |
| 272 | DENSURE(_d, _sz); \ |
| 273 | memcpy(_d->buf + _d->len, (p), _sz); \ |
| 274 | _d->len += _sz; \ |
| 275 | } while (0) |
| 276 | |
| 277 | /* --- @dstr_tidy@ --- * |
| 278 | * |
| 279 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 280 | * |
| 281 | * Returns: --- |
| 282 | * |
| 283 | * Use: Reduces the amount of memory used by a string. A trailing |
| 284 | * null byte is added, as for @dstr_putz@. |
| 285 | */ |
| 286 | |
| 287 | extern void dstr_tidy(dstr */*d*/); |
| 288 | |
| 289 | /* --- @dstr_putline@ --- * |
| 290 | * |
| 291 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 292 | * @FILE *fp@ = a stream to read from |
| 293 | * |
| 294 | * Returns: The number of characters read into the buffer, or @EOF@ if |
| 295 | * end-of-file was reached before any characters were read. |
| 296 | * |
| 297 | * Use: Appends the next line from the given input stream to the |
| 298 | * string. A trailing newline is not added; a trailing null |
| 299 | * byte is appended, as for @dstr_putz@. |
| 300 | */ |
| 301 | |
| 302 | extern int dstr_putline(dstr */*d*/, FILE */*fp*/); |
| 303 | |
| 304 | /* --- @dstr_write@ --- * |
| 305 | * |
| 306 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 307 | * @FILE *fp@ = a stream to write on |
| 308 | * |
| 309 | * Returns: The number of bytes written (as for @fwrite@). |
| 310 | * |
| 311 | * Use: Writes a dynamic string to a file. |
| 312 | */ |
| 313 | |
| 314 | extern size_t dstr_write(const dstr */*d*/, FILE */*fp*/); |
| 315 | |
| 316 | #define DWRITE(d, fp) fwrite((d)->buf, 1, (d)->len, (fp)) |
| 317 | |
| 318 | /*----- That's all, folks -------------------------------------------------*/ |
| 319 | |
| 320 | #ifdef __cplusplus |
| 321 | } |
| 322 | #endif |
| 323 | |
| 324 | #endif |