Annotation of src/usr.bin/less/decode.c, Revision 1.18
1.1 etheisen 1: /*
1.7 shadchin 2: * Copyright (C) 1984-2012 Mark Nudelman
1.10 nicm 3: * Modified for use with illumos by Garrett D'Amore.
4: * Copyright 2014 Garrett D'Amore <garrett@damore.org>
1.1 etheisen 5: *
1.4 millert 6: * You may distribute under the terms of either the GNU General Public
7: * License or the Less License, as specified in the README file.
1.1 etheisen 8: *
1.7 shadchin 9: * For more information, see the README file.
1.8 nicm 10: */
1.1 etheisen 11:
12: /*
13: * Routines to decode user commands.
14: *
15: * This is all table driven.
16: * A command table is a sequence of command descriptors.
17: * Each command descriptor is a sequence of bytes with the following format:
18: * <c1><c2>...<cN><0><action>
19: * The characters c1,c2,...,cN are the command string; that is,
20: * the characters which the user must type.
21: * It is terminated by a null <0> byte.
22: * The byte after the null byte is the action code associated
23: * with the command string.
24: * If an action byte is OR-ed with A_EXTRA, this indicates
25: * that the option byte is followed by an extra string.
26: *
27: * There may be many command tables.
28: * The first (default) table is built-in.
29: * Other tables are read in from "lesskey" files.
30: * All the tables are linked together and are searched in order.
31: */
32:
1.17 mmcc 33: #include "cmd.h"
1.1 etheisen 34: #include "less.h"
35: #include "lesskey.h"
36:
1.6 shadchin 37: extern int erase_char, erase2_char, kill_char;
1.8 nicm 38: extern int secure, less_is_more;
1.1 etheisen 39:
1.8 nicm 40: #define SK(k) \
1.4 millert 41: SK_SPECIAL_KEY, (k), 6, 1, 1, 1
1.1 etheisen 42: /*
43: * Command table is ordered roughly according to expected
44: * frequency of use, so the common commands are near the beginning.
45: */
1.4 millert 46:
1.1 etheisen 47: static unsigned char cmdtable[] =
48: {
1.8 nicm 49: '\r', 0, A_F_LINE,
50: '\n', 0, A_F_LINE,
51: 'e', 0, A_F_LINE,
52: 'j', 0, A_F_LINE,
53: SK(SK_DOWN_ARROW), 0, A_F_LINE,
54: CONTROL('E'), 0, A_F_LINE,
55: CONTROL('N'), 0, A_F_LINE,
56: 'k', 0, A_B_LINE,
57: 'y', 0, A_B_LINE,
58: CONTROL('Y'), 0, A_B_LINE,
59: SK(SK_CONTROL_K), 0, A_B_LINE,
60: CONTROL('P'), 0, A_B_LINE,
61: SK(SK_UP_ARROW), 0, A_B_LINE,
62: 'J', 0, A_FF_LINE,
63: 'K', 0, A_BF_LINE,
64: 'Y', 0, A_BF_LINE,
65: 'd', 0, A_F_SCROLL,
66: CONTROL('D'), 0, A_F_SCROLL,
67: 'u', 0, A_B_SCROLL,
68: CONTROL('U'), 0, A_B_SCROLL,
69: ' ', 0, A_F_SCREEN,
70: 'f', 0, A_F_SCREEN,
71: CONTROL('F'), 0, A_F_SCREEN,
72: CONTROL('V'), 0, A_F_SCREEN,
73: SK(SK_PAGE_DOWN), 0, A_F_SCREEN,
74: 'b', 0, A_B_SCREEN,
75: CONTROL('B'), 0, A_B_SCREEN,
76: ESC, 'v', 0, A_B_SCREEN,
77: SK(SK_PAGE_UP), 0, A_B_SCREEN,
78: 'z', 0, A_F_WINDOW,
79: 'w', 0, A_B_WINDOW,
80: ESC, ' ', 0, A_FF_SCREEN,
81: 'F', 0, A_F_FOREVER,
82: ESC, 'F', 0, A_F_UNTIL_HILITE,
83: 'R', 0, A_FREPAINT,
84: 'r', 0, A_REPAINT,
85: CONTROL('R'), 0, A_REPAINT,
86: CONTROL('L'), 0, A_REPAINT,
87: ESC, 'u', 0, A_UNDO_SEARCH,
88: 'g', 0, A_GOLINE,
89: SK(SK_HOME), 0, A_GOLINE,
90: '<', 0, A_GOLINE,
91: ESC, '<', 0, A_GOLINE,
92: 'p', 0, A_PERCENT,
93: '%', 0, A_PERCENT,
94: ESC, '[', 0, A_LSHIFT,
95: ESC, ']', 0, A_RSHIFT,
96: ESC, '(', 0, A_LSHIFT,
97: ESC, ')', 0, A_RSHIFT,
98: SK(SK_RIGHT_ARROW), 0, A_RSHIFT,
99: SK(SK_LEFT_ARROW), 0, A_LSHIFT,
100: '{', 0, A_F_BRACKET|A_EXTRA, '{', '}', 0,
101: '}', 0, A_B_BRACKET|A_EXTRA, '{', '}', 0,
102: '(', 0, A_F_BRACKET|A_EXTRA, '(', ')', 0,
103: ')', 0, A_B_BRACKET|A_EXTRA, '(', ')', 0,
104: '[', 0, A_F_BRACKET|A_EXTRA, '[', ']', 0,
105: ']', 0, A_B_BRACKET|A_EXTRA, '[', ']', 0,
106: ESC, CONTROL('F'), 0, A_F_BRACKET,
107: ESC, CONTROL('B'), 0, A_B_BRACKET,
108: 'G', 0, A_GOEND,
109: ESC, '>', 0, A_GOEND,
110: '>', 0, A_GOEND,
111: SK(SK_END), 0, A_GOEND,
112: 'P', 0, A_GOPOS,
113:
114: '0', 0, A_DIGIT,
115: '1', 0, A_DIGIT,
116: '2', 0, A_DIGIT,
117: '3', 0, A_DIGIT,
118: '4', 0, A_DIGIT,
119: '5', 0, A_DIGIT,
120: '6', 0, A_DIGIT,
121: '7', 0, A_DIGIT,
122: '8', 0, A_DIGIT,
123: '9', 0, A_DIGIT,
124: '.', 0, A_DIGIT,
125:
126: '=', 0, A_STAT,
127: CONTROL('G'), 0, A_STAT,
128: ':', 'f', 0, A_STAT,
129: '/', 0, A_F_SEARCH,
130: '?', 0, A_B_SEARCH,
131: ESC, '/', 0, A_F_SEARCH|A_EXTRA, '*', 0,
132: ESC, '?', 0, A_B_SEARCH|A_EXTRA, '*', 0,
133: 'n', 0, A_AGAIN_SEARCH,
134: ESC, 'n', 0, A_T_AGAIN_SEARCH,
135: 'N', 0, A_REVERSE_SEARCH,
136: ESC, 'N', 0, A_T_REVERSE_SEARCH,
137: '&', 0, A_FILTER,
138: 'm', 0, A_SETMARK,
139: '\'', 0, A_GOMARK,
140: CONTROL('X'), CONTROL('X'), 0, A_GOMARK,
141: 'E', 0, A_EXAMINE,
142: ':', 'e', 0, A_EXAMINE,
143: CONTROL('X'), CONTROL('V'), 0, A_EXAMINE,
144: ':', 'n', 0, A_NEXT_FILE,
145: ':', 'p', 0, A_PREV_FILE,
146: 't', 0, A_NEXT_TAG,
147: 'T', 0, A_PREV_TAG,
148: ':', 'x', 0, A_INDEX_FILE,
149: ':', 'd', 0, A_REMOVE_FILE,
150: ':', 't', 0, A_OPT_TOGGLE|A_EXTRA, 't', 0,
151: '|', 0, A_PIPE,
152: 'v', 0, A_VISUAL,
153: '+', 0, A_FIRSTCMD,
154:
155: 'H', 0, A_HELP,
156: 'h', 0, A_HELP,
157: SK(SK_F1), 0, A_HELP,
158: 'V', 0, A_VERSION,
159: 'q', 0, A_QUIT,
160: 'Q', 0, A_QUIT,
161: ':', 'q', 0, A_QUIT,
162: ':', 'Q', 0, A_QUIT,
163: 'Z', 'Z', 0, A_QUIT
164: };
165:
166: static unsigned char lesstable[] = {
167: '-', 0, A_OPT_TOGGLE,
168: 's', 0, A_OPT_TOGGLE|A_EXTRA, 'o', 0,
169: '_', 0, A_DISP_OPTION
170: };
171:
172: static unsigned char moretable[] = {
173: 's', 0, A_F_SKIP
1.1 etheisen 174: };
175:
176: static unsigned char edittable[] =
177: {
1.9 deraadt 178: '\t', 0, EC_F_COMPLETE, /* TAB */
1.8 nicm 179: '\17', 0, EC_B_COMPLETE, /* BACKTAB */
180: SK(SK_BACKTAB), 0, EC_B_COMPLETE, /* BACKTAB */
181: ESC, '\t', 0, EC_B_COMPLETE, /* ESC TAB */
182: CONTROL('L'), 0, EC_EXPAND, /* CTRL-L */
183: CONTROL('V'), 0, EC_LITERAL, /* BACKSLASH */
184: CONTROL('A'), 0, EC_LITERAL, /* BACKSLASH */
185: ESC, 'l', 0, EC_RIGHT, /* ESC l */
186: SK(SK_RIGHT_ARROW), 0, EC_RIGHT, /* RIGHTARROW */
187: ESC, 'h', 0, EC_LEFT, /* ESC h */
188: SK(SK_LEFT_ARROW), 0, EC_LEFT, /* LEFTARROW */
189: ESC, 'b', 0, EC_W_LEFT, /* ESC b */
190: ESC, SK(SK_LEFT_ARROW), 0, EC_W_LEFT, /* ESC LEFTARROW */
191: SK(SK_CTL_LEFT_ARROW), 0, EC_W_LEFT, /* CTRL-LEFTARROW */
192: ESC, 'w', 0, EC_W_RIGHT, /* ESC w */
193: ESC, SK(SK_RIGHT_ARROW), 0, EC_W_RIGHT, /* ESC RIGHTARROW */
194: SK(SK_CTL_RIGHT_ARROW), 0, EC_W_RIGHT, /* CTRL-RIGHTARROW */
195: ESC, 'i', 0, EC_INSERT, /* ESC i */
196: SK(SK_INSERT), 0, EC_INSERT, /* INSERT */
197: ESC, 'x', 0, EC_DELETE, /* ESC x */
198: SK(SK_DELETE), 0, EC_DELETE, /* DELETE */
199: ESC, 'X', 0, EC_W_DELETE, /* ESC X */
200: ESC, SK(SK_DELETE), 0, EC_W_DELETE, /* ESC DELETE */
201: SK(SK_CTL_DELETE), 0, EC_W_DELETE, /* CTRL-DELETE */
202: SK(SK_CTL_BACKSPACE), 0, EC_W_BACKSPACE, /* CTRL-BACKSPACE */
203: ESC, '\b', 0, EC_W_BACKSPACE, /* ESC BACKSPACE */
204: ESC, '0', 0, EC_HOME, /* ESC 0 */
205: SK(SK_HOME), 0, EC_HOME, /* HOME */
206: ESC, '$', 0, EC_END, /* ESC $ */
207: SK(SK_END), 0, EC_END, /* END */
208: ESC, 'k', 0, EC_UP, /* ESC k */
209: SK(SK_UP_ARROW), 0, EC_UP, /* UPARROW */
210: ESC, 'j', 0, EC_DOWN, /* ESC j */
211: SK(SK_DOWN_ARROW), 0, EC_DOWN, /* DOWNARROW */
212: CONTROL('G'), 0, EC_ABORT, /* CTRL-G */
1.1 etheisen 213: };
214:
215: /*
216: * Structure to support a list of command tables.
217: */
1.14 deraadt 218: struct tablelist {
1.1 etheisen 219: struct tablelist *t_next;
220: char *t_start;
221: char *t_end;
222: };
223:
224: /*
225: * List of command tables and list of line-edit tables.
226: */
227: static struct tablelist *list_fcmd_tables = NULL;
228: static struct tablelist *list_ecmd_tables = NULL;
1.4 millert 229: static struct tablelist *list_var_tables = NULL;
230: static struct tablelist *list_sysvar_tables = NULL;
1.1 etheisen 231:
232:
233: /*
1.4 millert 234: * Expand special key abbreviations in a command table.
235: */
1.8 nicm 236: static void
237: expand_special_keys(char *table, int len)
238: {
239: char *fm;
240: char *to;
241: int a;
1.4 millert 242: char *repl;
243: int klen;
244:
1.18 ! deraadt 245: for (fm = table; fm < table + len; ) {
1.4 millert 246: /*
247: * Rewrite each command in the table with any
248: * special key abbreviations expanded.
249: */
1.18 ! deraadt 250: for (to = fm; *fm != '\0'; ) {
1.8 nicm 251: if (*fm != SK_SPECIAL_KEY) {
1.4 millert 252: *to++ = *fm++;
253: continue;
254: }
255: /*
256: * After SK_SPECIAL_KEY, next byte is the type
257: * of special key (one of the SK_* contants),
258: * and the byte after that is the number of bytes,
259: * N, reserved by the abbreviation (including the
260: * SK_SPECIAL_KEY and key type bytes).
261: * Replace all N bytes with the actual bytes
262: * output by the special key on this terminal.
263: */
264: repl = special_key_str(fm[1]);
265: klen = fm[2] & 0377;
266: fm += klen;
1.8 nicm 267: if (repl == NULL || strlen(repl) > klen)
1.4 millert 268: repl = "\377";
269: while (*repl != '\0')
270: *to++ = *repl++;
271: }
272: *to++ = '\0';
273: /*
1.8 nicm 274: * Fill any unused bytes between end of command and
1.4 millert 275: * the action byte with A_SKIP.
276: */
277: while (to <= fm)
278: *to++ = A_SKIP;
279: fm++;
280: a = *fm++ & 0377;
1.8 nicm 281: if (a & A_EXTRA) {
1.4 millert 282: while (*fm++ != '\0')
283: continue;
284: }
285: }
286: }
287:
288: /*
1.1 etheisen 289: * Initialize the command lists.
290: */
1.8 nicm 291: void
292: init_cmds(void)
1.1 etheisen 293: {
294: /*
295: * Add the default command tables.
296: */
1.8 nicm 297: add_fcmd_table((char *)cmdtable, sizeof (cmdtable));
298: add_ecmd_table((char *)edittable, sizeof (edittable));
299: if (less_is_more) {
300: add_fcmd_table((char *)moretable, sizeof (moretable));
301: return;
302: } else {
303: add_fcmd_table((char *)lesstable, sizeof (lesstable));
304: }
305:
1.4 millert 306: /*
307: * Try to add the tables in the system lesskey file.
308: */
309: add_hometable("LESSKEY_SYSTEM", LESSKEYFILE_SYS, 1);
310: /*
1.1 etheisen 311: * Try to add the tables in the standard lesskey file "$HOME/.less".
312: */
1.4 millert 313: add_hometable("LESSKEY", LESSKEYFILE, 0);
1.1 etheisen 314: }
315:
316: /*
1.4 millert 317: * Add a command table.
1.1 etheisen 318: */
1.8 nicm 319: static int
320: add_cmd_table(struct tablelist **tlist, char *buf, int len)
1.1 etheisen 321: {
1.8 nicm 322: struct tablelist *t;
1.1 etheisen 323:
324: if (len == 0)
325: return (0);
326: /*
1.8 nicm 327: * Allocate a tablelist structure, initialize it,
1.1 etheisen 328: * and link it into the list of tables.
329: */
1.8 nicm 330: if ((t = calloc(1, sizeof (struct tablelist))) == NULL) {
1.1 etheisen 331: return (-1);
332: }
1.4 millert 333: expand_special_keys(buf, len);
1.1 etheisen 334: t->t_start = buf;
335: t->t_end = buf + len;
336: t->t_next = *tlist;
337: *tlist = t;
338: return (0);
339: }
340:
341: /*
342: * Add a command table.
343: */
1.8 nicm 344: void
345: add_fcmd_table(char *buf, int len)
1.1 etheisen 346: {
347: if (add_cmd_table(&list_fcmd_tables, buf, len) < 0)
1.15 deraadt 348: error("Warning: some commands disabled", NULL);
1.1 etheisen 349: }
350:
351: /*
352: * Add an editing command table.
353: */
1.8 nicm 354: void
355: add_ecmd_table(char *buf, int len)
1.1 etheisen 356: {
357: if (add_cmd_table(&list_ecmd_tables, buf, len) < 0)
1.15 deraadt 358: error("Warning: some edit commands disabled", NULL);
1.1 etheisen 359: }
360:
361: /*
1.4 millert 362: * Add an environment variable table.
363: */
1.8 nicm 364: static void
365: add_var_table(struct tablelist **tlist, char *buf, int len)
1.4 millert 366: {
367: if (add_cmd_table(tlist, buf, len) < 0)
1.8 nicm 368: error("Warning: environment variables from "
1.15 deraadt 369: "lesskey file unavailable", NULL);
1.4 millert 370: }
371:
372: /*
1.1 etheisen 373: * Search a single command table for the command string in cmd.
374: */
1.8 nicm 375: static int
376: cmd_search(const char *cmd, char *table, char *endtable, char **sp)
377: {
378: char *p;
379: const char *q;
380: int a;
1.1 etheisen 381:
1.4 millert 382: *sp = NULL;
1.18 ! deraadt 383: for (p = table, q = cmd; p < endtable; p++, q++) {
1.8 nicm 384: if (*p == *q) {
1.1 etheisen 385: /*
386: * Current characters match.
387: * If we're at the end of the string, we've found it.
388: * Return the action code, which is the character
389: * after the null at the end of the string
390: * in the command table.
391: */
1.8 nicm 392: if (*p == '\0') {
1.1 etheisen 393: a = *++p & 0377;
1.4 millert 394: while (a == A_SKIP)
395: a = *++p & 0377;
1.8 nicm 396: if (a == A_END_LIST) {
1.1 etheisen 397: /*
398: * We get here only if the original
399: * cmd string passed in was empty ("").
400: * I don't think that can happen,
401: * but just in case ...
402: */
403: return (A_UINVALID);
404: }
405: /*
406: * Check for an "extra" string.
407: */
1.8 nicm 408: if (a & A_EXTRA) {
1.1 etheisen 409: *sp = ++p;
410: a &= ~A_EXTRA;
1.4 millert 411: }
1.1 etheisen 412: return (a);
413: }
1.8 nicm 414: } else if (*q == '\0') {
1.1 etheisen 415: /*
416: * Hit the end of the user's command,
417: * but not the end of the string in the command table.
418: * The user's command is incomplete.
419: */
420: return (A_PREFIX);
1.8 nicm 421: } else {
1.1 etheisen 422: /*
423: * Not a match.
424: * Skip ahead to the next command in the
425: * command table, and reset the pointer
426: * to the beginning of the user's command.
427: */
1.8 nicm 428: if (*p == '\0' && p[1] == A_END_LIST) {
1.1 etheisen 429: /*
1.8 nicm 430: * A_END_LIST is a special marker that tells
1.1 etheisen 431: * us to abort the cmd search.
432: */
433: return (A_UINVALID);
434: }
1.4 millert 435: while (*p++ != '\0')
436: continue;
437: while (*p == A_SKIP)
438: p++;
1.1 etheisen 439: if (*p & A_EXTRA)
1.4 millert 440: while (*++p != '\0')
441: continue;
1.1 etheisen 442: q = cmd-1;
443: }
444: }
445: /*
446: * No match found in the entire command table.
447: */
448: return (A_INVALID);
449: }
450:
451: /*
452: * Decode a command character and return the associated action.
453: * The "extra" string, if any, is returned in sp.
454: */
1.8 nicm 455: static int
456: cmd_decode(struct tablelist *tlist, const char *cmd, char **sp)
1.1 etheisen 457: {
1.8 nicm 458: struct tablelist *t;
459: int action = A_INVALID;
1.1 etheisen 460:
461: /*
462: * Search thru all the command tables.
463: * Stop when we find an action which is not A_INVALID.
464: */
1.18 ! deraadt 465: for (t = tlist; t != NULL; t = t->t_next) {
1.1 etheisen 466: action = cmd_search(cmd, t->t_start, t->t_end, sp);
467: if (action != A_INVALID)
468: break;
469: }
1.4 millert 470: if (action == A_UINVALID)
471: action = A_INVALID;
1.1 etheisen 472: return (action);
473: }
474:
475: /*
476: * Decode a command from the cmdtables list.
477: */
1.8 nicm 478: int
479: fcmd_decode(const char *cmd, char **sp)
1.1 etheisen 480: {
481: return (cmd_decode(list_fcmd_tables, cmd, sp));
482: }
483:
484: /*
485: * Decode a command from the edittables list.
486: */
1.8 nicm 487: int
488: ecmd_decode(const char *cmd, char **sp)
1.1 etheisen 489: {
490: return (cmd_decode(list_ecmd_tables, cmd, sp));
491: }
492:
1.4 millert 493: /*
494: * Get the value of an environment variable.
495: * Looks first in the lesskey file, then in the real environment.
496: */
1.8 nicm 497: char *
498: lgetenv(char *var)
1.4 millert 499: {
500: int a;
501: char *s;
502:
1.8 nicm 503: /*
504: * Ignore lookups of any LESS* setting when we are more, and ignore
505: * the less key files
506: */
507: if (less_is_more) {
508: if (strncmp(var, "LESS", 4) == 0) {
509: return (NULL);
510: }
511: return (getenv(var));
512: }
1.4 millert 513: a = cmd_decode(list_var_tables, var, &s);
514: if (a == EV_OK)
515: return (s);
516: s = getenv(var);
517: if (s != NULL && *s != '\0')
518: return (s);
519: a = cmd_decode(list_sysvar_tables, var, &s);
520: if (a == EV_OK)
521: return (s);
522: return (NULL);
523: }
524:
525: /*
526: * Get an "integer" from a lesskey file.
1.8 nicm 527: * Integers are stored in a funny format:
1.4 millert 528: * two bytes, low order first, in radix KRADIX.
529: */
1.8 nicm 530: static int
531: gint(char **sp)
1.1 etheisen 532: {
533: int n;
534:
535: n = *(*sp)++;
536: n += *(*sp)++ * KRADIX;
537: return (n);
538: }
539:
1.4 millert 540: /*
541: * Process an old (pre-v241) lesskey file.
542: */
1.8 nicm 543: static int
544: old_lesskey(char *buf, int len)
1.1 etheisen 545: {
546: /*
547: * Old-style lesskey file.
1.8 nicm 548: * The file must end with either
1.9 deraadt 549: * ..,cmd,0,action
1.8 nicm 550: * or ...,cmd,0,action|A_EXTRA,string,0
1.1 etheisen 551: * So the last byte or the second to last byte must be zero.
552: */
553: if (buf[len-1] != '\0' && buf[len-2] != '\0')
554: return (-1);
555: add_fcmd_table(buf, len);
556: return (0);
557: }
558:
1.8 nicm 559: /*
1.4 millert 560: * Process a new (post-v241) lesskey file.
561: */
1.8 nicm 562: static int
563: new_lesskey(char *buf, int len, int sysvar)
1.1 etheisen 564: {
565: char *p;
1.8 nicm 566: int c;
567: int n;
1.1 etheisen 568:
569: /*
570: * New-style lesskey file.
571: * Extract the pieces.
572: */
573: if (buf[len-3] != C0_END_LESSKEY_MAGIC ||
574: buf[len-2] != C1_END_LESSKEY_MAGIC ||
575: buf[len-1] != C2_END_LESSKEY_MAGIC)
576: return (-1);
577: p = buf + 4;
1.8 nicm 578: for (;;) {
1.1 etheisen 579: c = *p++;
1.8 nicm 580: switch (c) {
1.1 etheisen 581: case CMD_SECTION:
582: n = gint(&p);
583: add_fcmd_table(p, n);
584: p += n;
585: break;
586: case EDIT_SECTION:
587: n = gint(&p);
588: add_ecmd_table(p, n);
589: p += n;
590: break;
1.4 millert 591: case VAR_SECTION:
592: n = gint(&p);
1.8 nicm 593: add_var_table((sysvar) ?
594: &list_sysvar_tables : &list_var_tables, p, n);
1.4 millert 595: p += n;
596: break;
1.1 etheisen 597: case END_SECTION:
1.4 millert 598: return (0);
1.1 etheisen 599: default:
1.4 millert 600: /*
601: * Unrecognized section type.
602: */
1.1 etheisen 603: return (-1);
604: }
605: }
606: }
607:
608: /*
609: * Set up a user command table, based on a "lesskey" file.
610: */
1.8 nicm 611: int
612: lesskey(char *filename, int sysvar)
1.1 etheisen 613: {
1.8 nicm 614: char *buf;
615: off_t len;
616: long n;
617: int f;
1.1 etheisen 618:
1.4 millert 619: if (secure)
620: return (1);
1.1 etheisen 621: /*
622: * Try to open the lesskey file.
623: */
1.4 millert 624: filename = shell_unquote(filename);
1.13 deraadt 625: f = open(filename, O_RDONLY);
1.4 millert 626: free(filename);
1.1 etheisen 627: if (f < 0)
628: return (1);
629:
630: /*
631: * Read the file into a buffer.
632: * We first figure out the size of the file and allocate space for it.
633: * {{ Minimal error checking is done here.
634: * A garbage .less file will produce strange results.
635: * To avoid a large amount of error checking code here, we
636: * rely on the lesskey program to generate a good .less file. }}
637: */
638: len = filesize(f);
1.8 nicm 639: if (len == -1 || len < 3) {
1.1 etheisen 640: /*
641: * Bad file (valid file must have at least 3 chars).
642: */
1.8 nicm 643: (void) close(f);
1.1 etheisen 644: return (-1);
645: }
1.8 nicm 646: if ((buf = calloc((int)len, sizeof (char))) == NULL) {
647: (void) close(f);
1.1 etheisen 648: return (-1);
649: }
1.16 deraadt 650: if (lseek(f, (off_t)0, SEEK_SET) == (off_t)-1) {
1.1 etheisen 651: free(buf);
1.8 nicm 652: (void) close(f);
1.1 etheisen 653: return (-1);
654: }
655: n = read(f, buf, (unsigned int) len);
656: close(f);
1.8 nicm 657: if (n != len) {
1.1 etheisen 658: free(buf);
659: return (-1);
660: }
661:
662: /*
663: * Figure out if this is an old-style (before version 241)
664: * or new-style lesskey file format.
665: */
666: if (buf[0] != C0_LESSKEY_MAGIC || buf[1] != C1_LESSKEY_MAGIC ||
667: buf[2] != C2_LESSKEY_MAGIC || buf[3] != C3_LESSKEY_MAGIC)
668: return (old_lesskey(buf, (int)len));
1.4 millert 669: return (new_lesskey(buf, (int)len, sysvar));
1.1 etheisen 670: }
671:
672: /*
673: * Add the standard lesskey file "$HOME/.less"
674: */
1.8 nicm 675: void
676: add_hometable(char *envname, char *def_filename, int sysvar)
1.1 etheisen 677: {
678: char *filename;
679: PARG parg;
680:
1.4 millert 681: if (envname != NULL && (filename = lgetenv(envname)) != NULL)
1.12 tedu 682: filename = estrdup(filename);
1.4 millert 683: else if (sysvar)
1.12 tedu 684: filename = estrdup(def_filename);
1.4 millert 685: else
686: filename = homefile(def_filename);
1.1 etheisen 687: if (filename == NULL)
688: return;
1.8 nicm 689: if (lesskey(filename, sysvar) < 0) {
1.1 etheisen 690: parg.p_string = filename;
691: error("Cannot use lesskey file \"%s\"", &parg);
692: }
693: free(filename);
694: }
695:
696: /*
697: * See if a char is a special line-editing command.
698: */
1.8 nicm 699: int
700: editchar(int c, int flags)
1.1 etheisen 701: {
702: int action;
703: int nch;
704: char *s;
705: char usercmd[MAX_CMDLEN+1];
1.8 nicm 706:
1.1 etheisen 707: /*
708: * An editing character could actually be a sequence of characters;
709: * for example, an escape sequence sent by pressing the uparrow key.
710: * To match the editing string, we use the command decoder
711: * but give it the edit-commands command table
712: * This table is constructed to match the user's keyboard.
713: */
1.6 shadchin 714: if (c == erase_char || c == erase2_char)
1.1 etheisen 715: return (EC_BACKSPACE);
716: if (c == kill_char)
717: return (EC_LINEKILL);
1.8 nicm 718:
1.1 etheisen 719: /*
720: * Collect characters in a buffer.
721: * Start with the one we have, and get more if we need them.
722: */
723: nch = 0;
724: do {
1.8 nicm 725: if (nch > 0)
1.1 etheisen 726: c = getcc();
1.8 nicm 727: usercmd[nch] = (char)c;
1.1 etheisen 728: usercmd[nch+1] = '\0';
729: nch++;
730: action = ecmd_decode(usercmd, &s);
731: } while (action == A_PREFIX);
1.8 nicm 732:
733: if (flags & EC_NORIGHTLEFT) {
734: switch (action) {
1.4 millert 735: case EC_RIGHT:
736: case EC_LEFT:
737: action = A_INVALID;
738: break;
739: }
740: }
1.8 nicm 741: if (flags & EC_NOHISTORY) {
1.1 etheisen 742: /*
743: * The caller says there is no history list.
744: * Reject any history-manipulation action.
745: */
1.8 nicm 746: switch (action) {
1.1 etheisen 747: case EC_UP:
748: case EC_DOWN:
749: action = A_INVALID;
750: break;
751: }
752: }
1.8 nicm 753: if (flags & EC_NOCOMPLETE) {
1.1 etheisen 754: /*
755: * The caller says we don't want any filename completion cmds.
756: * Reject them.
757: */
1.8 nicm 758: switch (action) {
1.1 etheisen 759: case EC_F_COMPLETE:
760: case EC_B_COMPLETE:
761: case EC_EXPAND:
762: action = A_INVALID;
763: break;
764: }
765: }
1.8 nicm 766: if ((flags & EC_PEEK) || action == A_INVALID) {
1.1 etheisen 767: /*
768: * We're just peeking, or we didn't understand the command.
769: * Unget all the characters we read in the loop above.
1.8 nicm 770: * This does NOT include the original character that was
1.1 etheisen 771: * passed in as a parameter.
772: */
1.8 nicm 773: while (nch > 1) {
1.1 etheisen 774: ungetcc(usercmd[--nch]);
775: }
1.8 nicm 776: } else {
1.1 etheisen 777: if (s != NULL)
778: ungetsc(s);
779: }
1.8 nicm 780: return (action);
1.1 etheisen 781: }