| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: util.c,v 1.1 2001/02/04 17:14:42 mdw Exp $ |
| 4 | * |
| 5 | * Various useful utilities, stolen from mLib |
| 6 | * |
| 7 | * (c) 2001 Mark Wooding |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Anag: a simple wordgame helper. |
| 13 | * |
| 14 | * Anag 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 | * Anag 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 Anag; 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: util.c,v $ |
| 32 | * Revision 1.1 2001/02/04 17:14:42 mdw |
| 33 | * Initial checkin |
| 34 | * |
| 35 | */ |
| 36 | |
| 37 | /*----- Header files ------------------------------------------------------*/ |
| 38 | |
| 39 | #include "anag.h" |
| 40 | |
| 41 | /*----- Static variables --------------------------------------------------*/ |
| 42 | |
| 43 | static const char *quis = "<unset>"; |
| 44 | |
| 45 | /*----- Error reporting ---------------------------------------------------*/ |
| 46 | |
| 47 | /* --- @ego@ --- * |
| 48 | * |
| 49 | * Arguments: @const char *p@ = pointer to program name |
| 50 | * |
| 51 | * Returns: --- |
| 52 | * |
| 53 | * Use: Stores what the program's name is. |
| 54 | */ |
| 55 | |
| 56 | #ifndef PATHSEP |
| 57 | # if defined(__riscos) |
| 58 | # define PATHSEP '.' |
| 59 | # elif defined(__unix) || defined(unix) |
| 60 | # define PATHSEP '/' |
| 61 | # else |
| 62 | # define PATHSEP '\\' |
| 63 | # endif |
| 64 | #endif |
| 65 | |
| 66 | void ego(const char *p) |
| 67 | { |
| 68 | const char *q = p; |
| 69 | while (*q) { |
| 70 | if (*q++ == PATHSEP) |
| 71 | p = q; |
| 72 | } |
| 73 | if (*p == '-') |
| 74 | p++; |
| 75 | quis = p; |
| 76 | } |
| 77 | |
| 78 | #undef PATHSEP |
| 79 | |
| 80 | /* --- @pquis@ --- * |
| 81 | * |
| 82 | * Arguments: @FILE *fp@ = output stream to write on |
| 83 | * @const char *p@ = pointer to string to write |
| 84 | * |
| 85 | * Returns: Zero if everything worked, EOF if not. |
| 86 | * |
| 87 | * Use: Writes the string @p@ to the output stream @fp@. Occurrences |
| 88 | * of the character `$' in @p@ are replaced by the program name |
| 89 | * as reported by @quis@. A `$$' is replaced by a single `$' |
| 90 | * sign. |
| 91 | */ |
| 92 | |
| 93 | int pquis(FILE *fp, const char *p) |
| 94 | { |
| 95 | size_t sz; |
| 96 | |
| 97 | while (*p) { |
| 98 | sz = strcspn(p, "$"); |
| 99 | if (sz) { |
| 100 | if (fwrite(p, 1, sz, fp) < sz) |
| 101 | return (EOF); |
| 102 | p += sz; |
| 103 | } |
| 104 | if (*p == '$') { |
| 105 | p++; |
| 106 | if (*p == '$') { |
| 107 | if (fputc('$', fp) == EOF) |
| 108 | return (EOF); |
| 109 | p++; |
| 110 | } else { |
| 111 | if (fputs(quis, fp) == EOF) |
| 112 | return (EOF); |
| 113 | } |
| 114 | } |
| 115 | } |
| 116 | return (0); |
| 117 | } |
| 118 | |
| 119 | /* --- @die@ --- * |
| 120 | * |
| 121 | * Arguments: @const char *f@ = a @printf@-style format string |
| 122 | * @...@ = other arguments |
| 123 | * |
| 124 | * Returns: Never. |
| 125 | * |
| 126 | * Use: Reports an error and exits. |
| 127 | */ |
| 128 | |
| 129 | void die(const char *f, ...) |
| 130 | { |
| 131 | va_list ap; |
| 132 | va_start(ap, f); |
| 133 | fprintf(stderr, "%s: ", quis); |
| 134 | vfprintf(stderr, f, ap); |
| 135 | va_end(ap); |
| 136 | putc('\n', stderr); |
| 137 | exit(EXIT_FAILURE); |
| 138 | } |
| 139 | |
| 140 | /*----- Memory allocation -------------------------------------------------*/ |
| 141 | |
| 142 | /* --- @xmalloc@ --- * |
| 143 | * |
| 144 | * Arguments: @size_t sz@ = size of block to allocate |
| 145 | * |
| 146 | * Returns: Pointer to allocated block. |
| 147 | * |
| 148 | * Use: Allocates memory. If there's not enough memory, the |
| 149 | * program exits. |
| 150 | */ |
| 151 | |
| 152 | void *xmalloc(size_t sz) |
| 153 | { |
| 154 | void *p = malloc(sz); |
| 155 | if (!p) |
| 156 | die("not enough memory"); |
| 157 | return (p); |
| 158 | } |
| 159 | |
| 160 | /* --- @xrealloc@ --- * |
| 161 | * |
| 162 | * Arguments: @void *p@ = a pointer to allocated memory |
| 163 | * @size_t sz@ = new size of block wanted |
| 164 | * |
| 165 | * Returns: Pointer to resized block. |
| 166 | * |
| 167 | * Use: Resizes an allocated block. If there's not enough memory, |
| 168 | * the program exits. |
| 169 | */ |
| 170 | |
| 171 | void *xrealloc(void *p, size_t sz) |
| 172 | { |
| 173 | p = realloc(p, sz); |
| 174 | if (!p) |
| 175 | die("not enough memory"); |
| 176 | return (p); |
| 177 | } |
| 178 | |
| 179 | /*----- Dynamic string handling -------------------------------------------*/ |
| 180 | |
| 181 | #define DSTR_INITSZ 64 |
| 182 | |
| 183 | /* --- @dstr_destroy@ --- * |
| 184 | * |
| 185 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 186 | * |
| 187 | * Returns: --- |
| 188 | * |
| 189 | * Use: Reclaims the space used by a dynamic string. |
| 190 | */ |
| 191 | |
| 192 | void dstr_destroy(dstr *d) { free(d->buf); d->len = 0; d->sz = 0; } |
| 193 | |
| 194 | /* --- @dstr_reset@ --- * |
| 195 | * |
| 196 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 197 | * |
| 198 | * Returns: --- |
| 199 | * |
| 200 | * Use: Resets a string so that new data gets put at the beginning. |
| 201 | */ |
| 202 | |
| 203 | void dstr_reset(dstr *d) { d->len = 0; } |
| 204 | |
| 205 | /* --- @dstr_ensure@ --- * |
| 206 | * |
| 207 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 208 | * @size_t sz@ = amount of free space to ensure |
| 209 | * |
| 210 | * Returns: --- |
| 211 | * |
| 212 | * Use: Ensures that at least @sz@ bytes are available in the |
| 213 | * given string. |
| 214 | */ |
| 215 | |
| 216 | void dstr_ensure(dstr *d, size_t sz) |
| 217 | { |
| 218 | size_t rq = d->len + sz; |
| 219 | size_t nsz; |
| 220 | |
| 221 | /* --- If we have enough space, just leave it --- */ |
| 222 | |
| 223 | if (rq <= d->sz) |
| 224 | return; |
| 225 | |
| 226 | /* --- Grow the buffer --- */ |
| 227 | |
| 228 | nsz = d->sz; |
| 229 | |
| 230 | if (nsz == 0) |
| 231 | nsz = (DSTR_INITSZ >> 1); |
| 232 | do nsz <<= 1; while (nsz < rq); |
| 233 | |
| 234 | if (d->buf) |
| 235 | d->buf = xrealloc(d->buf, nsz); |
| 236 | else |
| 237 | d->buf = xmalloc(nsz); |
| 238 | d->sz = nsz; |
| 239 | } |
| 240 | |
| 241 | /* --- @dstr_putline@ --- * |
| 242 | * |
| 243 | * Arguments: @dstr *d@ = pointer to a dynamic string block |
| 244 | * @FILE *fp@ = a stream to read from |
| 245 | * |
| 246 | * Returns: The number of characters read into the buffer, or @EOF@ if |
| 247 | * end-of-file was reached before any characters were read. |
| 248 | * |
| 249 | * Use: Appends the next line from the given input stream to the |
| 250 | * string. A trailing newline is not added; a trailing null |
| 251 | * byte is appended, as for @dstr_putz@. |
| 252 | */ |
| 253 | |
| 254 | int dstr_putline(dstr *d, FILE *fp) |
| 255 | { |
| 256 | size_t left = d->sz - d->len; |
| 257 | size_t off = d->len; |
| 258 | int rd = 0; |
| 259 | int ch; |
| 260 | |
| 261 | for (;;) { |
| 262 | |
| 263 | /* --- Read the next byte --- */ |
| 264 | |
| 265 | ch = getc(fp); |
| 266 | |
| 267 | /* --- End-of-file when no characters read is special --- */ |
| 268 | |
| 269 | if (ch == EOF && !rd) |
| 270 | return (EOF); |
| 271 | |
| 272 | /* --- Make sure there's some buffer space --- */ |
| 273 | |
| 274 | if (!left) { |
| 275 | d->len = off; |
| 276 | dstr_ensure(d, 1); |
| 277 | left = d->sz - off; |
| 278 | } |
| 279 | |
| 280 | /* --- End-of-file or newline ends the loop --- */ |
| 281 | |
| 282 | if (ch == EOF || ch == '\n') { |
| 283 | d->buf[off] = 0; |
| 284 | d->len = off; |
| 285 | return rd; |
| 286 | } |
| 287 | |
| 288 | /* --- Append the character and continue --- */ |
| 289 | |
| 290 | d->buf[off++] = ch; |
| 291 | left--; rd++; |
| 292 | } |
| 293 | } |
| 294 | |
| 295 | /*----- That's all, folks -------------------------------------------------*/ |