1 /* $OpenBSD: prompt.c,v 1.5 2001/11/19 19:02:14 mpech Exp $ */ 2 3 /* 4 * Copyright (c) 1984,1985,1989,1994,1995 Mark Nudelman 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice in the documentation and/or other materials provided with 14 * the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY 17 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 22 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 23 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE 25 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN 26 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 30 /* 31 * Prompting and other messages. 32 * There are three flavors of prompts, SHORT, MEDIUM and LONG, 33 * selected by the -m/-M options. 34 * There is also the "equals message", printed by the = command. 35 * A prompt is a message composed of various pieces, such as the 36 * name of the file being viewed, the percentage into the file, etc. 37 */ 38 39 #include "less.h" 40 #include "position.h" 41 42 extern int pr_type; 43 extern int hit_eof; 44 extern int new_file; 45 extern int sc_width; 46 extern int so_s_width, so_e_width; 47 extern int linenums; 48 extern int sc_height; 49 extern int jump_sline; 50 extern IFILE curr_ifile; 51 #if EDITOR 52 extern char *editor; 53 #endif 54 55 /* 56 * Prototypes for the three flavors of prompts. 57 * These strings are expanded by pr_expand(). 58 */ 59 static char s_proto[] = 60 "?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\\: %x..%t"; 61 static char m_proto[] = 62 "?f%f .?m(file %i of %m) .?e(END) ?x- Next\\: %x.:(?pB%pB\\%:byte %bB?s/%s..).%t"; 63 static char M_proto[] = 64 "?f%f .?n?m(file %i of %m) ..?ltline %lt?L/%L. :byte %bB?s/%s. .?e(END) ?x- Next\\: %x.:?pB%pB\\%..%t"; 65 static char e_proto[] = 66 "?f%f .?m(file %i of %m) .?ltline %lt?L/%L. .byte %bB?s/%s. ?e(END) :?pB%pB\\%..%t"; 67 68 public char *prproto[3]; 69 public char *eqproto = e_proto; 70 71 static char message[250]; 72 static char *mp; 73 74 /* 75 * Initialize the prompt prototype strings. 76 */ 77 public void 78 init_prompt() 79 { 80 prproto[0] = save(s_proto); 81 prproto[1] = save(m_proto); 82 prproto[2] = save(M_proto); 83 eqproto = save(e_proto); 84 } 85 86 /* 87 * Set the message pointer to the end of the message string. 88 */ 89 static void 90 setmp() 91 { 92 while (*mp != '\0') 93 mp++; 94 } 95 96 /* 97 * Append a POSITION (as a decimal integer) to the end of the message. 98 */ 99 static void 100 ap_pos(pos) 101 POSITION pos; 102 { 103 sprintf(mp, "%qd", pos); 104 setmp(); 105 } 106 107 /* 108 * Append an integer to the end of the message. 109 */ 110 static void 111 ap_int(n) 112 int n; 113 { 114 sprintf(mp, "%d", n); 115 setmp(); 116 } 117 118 /* 119 * Append a string to the end of the message. 120 */ 121 static void 122 ap_str(s) 123 char *s; 124 { 125 strtcpy(mp, s, (unsigned int)(&message[sizeof(message)] - mp)); 126 setmp(); 127 } 128 129 /* 130 * Append a question mark to the end of the message. 131 */ 132 static void 133 ap_quest() 134 { 135 *mp++ = '?'; 136 } 137 138 /* 139 * Return the "current" byte offset in the file. 140 */ 141 static POSITION 142 curr_byte(where) 143 int where; 144 { 145 POSITION pos; 146 147 pos = position(where); 148 while (pos == NULL_POSITION && where >= 0 && where < sc_height) 149 pos = position(++where); 150 if (pos == NULL_POSITION) 151 pos = ch_length(); 152 return (pos); 153 } 154 155 /* 156 * Return the value of a prototype conditional. 157 * A prototype string may include conditionals which consist of a 158 * question mark followed by a single letter. 159 * Here we decode that letter and return the appropriate boolean value. 160 */ 161 static int 162 cond(c, where) 163 char c; 164 int where; 165 { 166 switch (c) 167 { 168 case 'a': /* Anything in the message yet? */ 169 return (mp > message); 170 case 'b': /* Current byte offset known? */ 171 return (curr_byte(where) != NULL_POSITION); 172 case 'e': /* At end of file? */ 173 return (hit_eof); 174 case 'f': /* Filename known? */ 175 return (strcmp(get_filename(curr_ifile), "-") != 0); 176 case 'l': /* Line number known? */ 177 return (linenums); 178 case 'L': /* Final line number known? */ 179 return (linenums && ch_length() != NULL_POSITION); 180 case 'm': /* More than one file? */ 181 return (nifile() > 1); 182 case 'n': /* First prompt in a new file? */ 183 return (new_file); 184 case 'p': /* Percent into file known? */ 185 return (curr_byte(where) != NULL_POSITION && 186 ch_length() > 0); 187 case 's': /* Size of file known? */ 188 case 'B': 189 return (ch_length() != NULL_POSITION); 190 case 'x': /* Is there a "next" file? */ 191 return (next_ifile(curr_ifile) != NULL_IFILE); 192 } 193 return (0); 194 } 195 196 /* 197 * Decode a "percent" prototype character. 198 * A prototype string may include various "percent" escapes; 199 * that is, a percent sign followed by a single letter. 200 * Here we decode that letter and take the appropriate action, 201 * usually by appending something to the message being built. 202 */ 203 static void 204 protochar(c, where) 205 int c; 206 int where; 207 { 208 POSITION pos; 209 POSITION len; 210 int n; 211 IFILE h; 212 213 switch (c) 214 { 215 case 'b': /* Current byte offset */ 216 pos = curr_byte(where); 217 if (pos != NULL_POSITION) 218 ap_pos(pos); 219 else 220 ap_quest(); 221 break; 222 #if EDITOR 223 case 'E': /* Editor name */ 224 ap_str(editor); 225 break; 226 #endif 227 case 'f': /* File name */ 228 ap_str(get_filename(curr_ifile)); 229 break; 230 case 'i': /* Index into list of files */ 231 ap_int(get_index(curr_ifile)); 232 break; 233 case 'l': /* Current line number */ 234 n = currline(where); 235 if (n != 0) 236 ap_int(n); 237 else 238 ap_quest(); 239 break; 240 case 'L': /* Final line number */ 241 len = ch_length(); 242 if (len == NULL_POSITION || len == ch_zero() || 243 (n = find_linenum(len)) <= 0) 244 ap_quest(); 245 else 246 ap_int(n-1); 247 break; 248 case 'm': /* Number of files */ 249 ap_int(nifile()); 250 break; 251 case 'p': /* Percent into file */ 252 pos = curr_byte(where); 253 len = ch_length(); 254 if (pos != NULL_POSITION && len > 0) 255 ap_int(percentage(pos,len)); 256 else 257 ap_quest(); 258 break; 259 case 's': /* Size of file */ 260 case 'B': 261 len = ch_length(); 262 if (len != NULL_POSITION) 263 ap_pos(len); 264 else 265 ap_quest(); 266 break; 267 case 't': /* Truncate trailing spaces in the message */ 268 while (mp > message && mp[-1] == ' ') 269 mp--; 270 break; 271 case 'x': /* Name of next file */ 272 h = next_ifile(curr_ifile); 273 if (h != NULL_IFILE) 274 ap_str(get_filename(h)); 275 else 276 ap_quest(); 277 break; 278 } 279 } 280 281 /* 282 * Skip a false conditional. 283 * When a false condition is found (either a false IF or the ELSE part 284 * of a true IF), this routine scans the prototype string to decide 285 * where to resume parsing the string. 286 * We must keep track of nested IFs and skip them properly. 287 */ 288 static char * 289 skipcond(p) 290 char *p; 291 { 292 int iflevel; 293 294 /* 295 * We came in here after processing a ? or :, 296 * so we start nested one level deep. 297 */ 298 iflevel = 1; 299 300 for (;;) switch (*++p) 301 { 302 case '?': 303 /* 304 * Start of a nested IF. 305 */ 306 iflevel++; 307 break; 308 case ':': 309 /* 310 * Else. 311 * If this matches the IF we came in here with, 312 * then we're done. 313 */ 314 if (iflevel == 1) 315 return (p); 316 break; 317 case '.': 318 /* 319 * Endif. 320 * If this matches the IF we came in here with, 321 * then we're done. 322 */ 323 if (--iflevel == 0) 324 return (p); 325 break; 326 case '\\': 327 /* 328 * Backslash escapes the next character. 329 */ 330 ++p; 331 break; 332 case '\0': 333 /* 334 * Whoops. Hit end of string. 335 * This is a malformed conditional, but just treat it 336 * as if all active conditionals ends here. 337 */ 338 return (p-1); 339 } 340 /*NOTREACHED*/ 341 } 342 343 static char * 344 wherechar(p, wp) 345 char *p; 346 int *wp; 347 { 348 switch (*p) 349 { 350 case 'b': case 'l': case 'p': 351 switch (*++p) 352 { 353 case 't': *wp = TOP; break; 354 case 'm': *wp = MIDDLE; break; 355 case 'b': *wp = BOTTOM; break; 356 case 'B': *wp = BOTTOM_PLUS_ONE; break; 357 case 'j': *wp = adjsline(jump_sline); break; 358 default: *wp = TOP; p--; break; 359 } 360 } 361 return (p); 362 } 363 364 /* 365 * Construct a message based on a prototype string. 366 */ 367 public char * 368 pr_expand(proto, maxwidth) 369 char *proto; 370 int maxwidth; 371 { 372 char *p; 373 int c; 374 int where; 375 376 mp = message; 377 378 if (*proto == '\0') 379 return (""); 380 381 for (p = proto; *p != '\0'; p++) 382 { 383 switch (*p) 384 { 385 default: /* Just put the character in the message */ 386 *mp++ = *p; 387 break; 388 case '\\': /* Backslash escapes the next character */ 389 p++; 390 *mp++ = *p; 391 break; 392 case '?': /* Conditional (IF) */ 393 if ((c = *++p) == '\0') 394 --p; 395 else 396 { 397 p = wherechar(p, &where); 398 if (!cond(c, where)) 399 p = skipcond(p); 400 } 401 break; 402 case ':': /* ELSE */ 403 p = skipcond(p); 404 break; 405 case '.': /* ENDIF */ 406 break; 407 case '%': /* Percent escape */ 408 if ((c = *++p) == '\0') 409 --p; 410 else 411 { 412 p = wherechar(p, &where); 413 protochar(c, where); 414 } 415 break; 416 } 417 } 418 419 new_file = 0; 420 if (mp == message) 421 return (NULL); 422 *mp = '\0'; 423 if (maxwidth > 0 && mp >= message + maxwidth) 424 { 425 /* 426 * Message is too long. 427 * Return just the final portion of it. 428 */ 429 return (mp - maxwidth); 430 } 431 return (message); 432 } 433 434 /* 435 * Return a message suitable for printing by the "=" command. 436 */ 437 public char * 438 eq_message() 439 { 440 return (pr_expand(eqproto, 0)); 441 } 442 443 /* 444 * Return a prompt. 445 * This depends on the prompt type (SHORT, MEDIUM, LONG), etc. 446 * If we can't come up with an appropriate prompt, return NULL 447 * and the caller will prompt with a colon. 448 */ 449 public char * 450 pr_string() 451 { 452 return (pr_expand(prproto[pr_type], sc_width-so_s_width-so_e_width-2)); 453 } 454