1 /**************************************************************************** 2 * Copyright (c) 2005-2006,2007 Free Software Foundation, Inc. * 3 * * 4 * Permission is hereby granted, free of charge, to any person obtaining a * 5 * copy of this software and associated documentation files (the * 6 * "Software"), to deal in the Software without restriction, including * 7 * without limitation the rights to use, copy, modify, merge, publish, * 8 * distribute, distribute with modifications, sublicense, and/or sell * 9 * copies of the Software, and to permit persons to whom the Software is * 10 * furnished to do so, subject to the following conditions: * 11 * * 12 * The above copyright notice and this permission notice shall be included * 13 * in all copies or substantial portions of the Software. * 14 * * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * 16 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * 17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * 18 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * 19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * 20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR * 21 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. * 22 * * 23 * Except as contained in this notice, the name(s) of the above copyright * 24 * holders shall not be used in advertising or otherwise to promote the * 25 * sale, use or other dealings in this Software without prior written * 26 * authorization. * 27 ****************************************************************************/ 28 29 /**************************************************************************** 30 * Author: Thomas Dickey * 31 ****************************************************************************/ 32 33 #include <curses.priv.h> 34 35 #include <ctype.h> 36 37 #include <tic.h> 38 #include <term_entry.h> 39 40 MODULE_ID("$Id: trim_sgr0.c,v 1.8 2007/04/07 17:14:11 tom Exp $") 41 42 #undef CUR 43 #define CUR tp-> 44 45 #define CSI 233 46 #define ESC 033 /* ^[ */ 47 #define L_BRACK '[' 48 49 static char * 50 set_attribute_9(TERMTYPE *tp, int flag) 51 { 52 const char *result; 53 54 if ((result = tparm(set_attributes, 0, 0, 0, 0, 0, 0, 0, 0, flag)) == 0) 55 result = ""; 56 return strdup(result); 57 } 58 59 static int 60 is_csi(const char *s) 61 { 62 if (UChar(s[0]) == CSI) 63 return 1; 64 else if (s[0] == ESC && s[1] == L_BRACK) 65 return 2; 66 return 0; 67 } 68 69 static char * 70 skip_zero(char *s) 71 { 72 if (s[0] == '0') { 73 if (s[1] == ';') 74 s += 2; 75 else if (isalpha(UChar(s[1]))) 76 s += 1; 77 } 78 return s; 79 } 80 81 static const char * 82 skip_delay(const char *s) 83 { 84 if (s[0] == '$' && s[1] == '<') { 85 s += 2; 86 while (isdigit(UChar(*s)) || *s == '/') 87 ++s; 88 if (*s == '>') 89 ++s; 90 } 91 return s; 92 } 93 94 /* 95 * Improve similar_sgr a little by moving the attr-string from the beginning 96 * to the end of the s-string. 97 */ 98 static bool 99 rewrite_sgr(char *s, char *attr) 100 { 101 if (PRESENT(s)) { 102 if (PRESENT(attr)) { 103 unsigned len_s = strlen(s); 104 unsigned len_a = strlen(attr); 105 106 if (len_s > len_a && !strncmp(attr, s, len_a)) { 107 unsigned n; 108 TR(TRACE_DATABASE, ("rewrite:\n\t%s", s)); 109 for (n = 0; n < len_s - len_a; ++n) { 110 s[n] = s[n + len_a]; 111 } 112 strcpy(s + n, attr); 113 TR(TRACE_DATABASE, ("to:\n\t%s", s)); 114 } 115 } 116 return TRUE; 117 } 118 return FALSE; /* oops */ 119 } 120 121 static bool 122 similar_sgr(char *a, char *b) 123 { 124 bool result = FALSE; 125 int csi_a = is_csi(a); 126 int csi_b = is_csi(b); 127 unsigned len_a; 128 unsigned len_b; 129 130 TR(TRACE_DATABASE, ("similar_sgr:\n\t%s\n\t%s", 131 _nc_visbuf2(1, a), 132 _nc_visbuf2(2, b))); 133 if (csi_a != 0 && csi_b != 0 && csi_a == csi_b) { 134 a += csi_a; 135 b += csi_b; 136 if (*a != *b) { 137 a = skip_zero(a); 138 b = skip_zero(b); 139 } 140 } 141 len_a = strlen(a); 142 len_b = strlen(b); 143 if (len_a && len_b) { 144 if (len_a > len_b) 145 result = (strncmp(a, b, len_b) == 0); 146 else 147 result = (strncmp(a, b, len_a) == 0); 148 } 149 TR(TRACE_DATABASE, ("...similar_sgr: %d\n\t%s\n\t%s", result, 150 _nc_visbuf2(1, a), 151 _nc_visbuf2(2, b))); 152 return result; 153 } 154 155 static unsigned 156 chop_out(char *string, unsigned i, unsigned j) 157 { 158 TR(TRACE_DATABASE, ("chop_out %d..%d from %s", i, j, _nc_visbuf(string))); 159 while (string[j] != '\0') { 160 string[i++] = string[j++]; 161 } 162 string[i] = '\0'; 163 return i; 164 } 165 166 /* 167 * Compare, ignoring delays. Some of the delay values are inconsistent, and 168 * we do not want to be stopped by that. 169 * 170 * Returns the number of chars from 'full' that we matched. If any mismatch 171 * occurs, return zero. 172 */ 173 static int 174 compare_part(const char *part, const char *full) 175 { 176 const char *next_part; 177 const char *next_full; 178 int used_full = 0; 179 int used_delay = 0; 180 181 while (*part != 0) { 182 if (*part != *full) { 183 used_full = 0; 184 break; 185 } 186 187 /* 188 * Adjust the return-value to allow the rare case of 189 * string<delay>string 190 * to remove the whole piece. The most common case is a delay at the 191 * end of the string. The adjusted string will retain the delay, which 192 * is conservative. 193 */ 194 if (used_delay != 0) { 195 used_full += used_delay; 196 used_delay = 0; 197 } 198 if (*part == '$' && *full == '$') { 199 next_part = skip_delay(part); 200 next_full = skip_delay(full); 201 if (next_part != part && next_full != full) { 202 used_delay += (next_full - full); 203 full = next_full; 204 part = next_part; 205 continue; 206 } 207 } 208 ++used_full; 209 ++part; 210 ++full; 211 } 212 return used_full; 213 } 214 215 /* 216 * While 'sgr0' is the "same" as termcap 'me', there is a compatibility issue. 217 * The sgr/sgr0 capabilities include setting/clearing alternate character set 218 * mode. A termcap application cannot use sgr, so sgr0 strings that reset 219 * alternate character set mode will be misinterpreted. Here, we remove those 220 * from the more common ISO/ANSI/VT100 entries, which have sgr0 agreeing with 221 * sgr. 222 * 223 * This function returns the modified sgr0 if it can be modified, a null if 224 * an error occurs, or the original sgr0 if no change is needed. 225 */ 226 NCURSES_EXPORT(char *) 227 _nc_trim_sgr0(TERMTYPE *tp) 228 { 229 char *result = exit_attribute_mode; 230 231 T((T_CALLED("_nc_trim_sgr0()"))); 232 233 if (PRESENT(exit_attribute_mode) 234 && PRESENT(set_attributes)) { 235 bool found = FALSE; 236 char *on = set_attribute_9(tp, 1); 237 char *off = set_attribute_9(tp, 0); 238 char *end = strdup(exit_attribute_mode); 239 char *tmp; 240 size_t i, j, k; 241 242 TR(TRACE_DATABASE, ("checking if we can trim sgr0 based on sgr")); 243 TR(TRACE_DATABASE, ("sgr0 %s", _nc_visbuf(end))); 244 TR(TRACE_DATABASE, ("sgr(9:off) %s", _nc_visbuf(off))); 245 TR(TRACE_DATABASE, ("sgr(9:on) %s", _nc_visbuf(on))); 246 247 if (!rewrite_sgr(on, enter_alt_charset_mode) 248 || !rewrite_sgr(off, exit_alt_charset_mode) 249 || !rewrite_sgr(end, exit_alt_charset_mode)) { 250 FreeIfNeeded(off); 251 } else if (similar_sgr(off, end) 252 && !similar_sgr(off, on)) { 253 TR(TRACE_DATABASE, ("adjusting sgr(9:off) : %s", _nc_visbuf(off))); 254 result = off; 255 /* 256 * If rmacs is a substring of sgr(0), remove that chunk. 257 */ 258 if (exit_alt_charset_mode != 0) { 259 TR(TRACE_DATABASE, ("scan for rmacs %s", _nc_visbuf(exit_alt_charset_mode))); 260 j = strlen(off); 261 k = strlen(exit_alt_charset_mode); 262 if (j > k) { 263 for (i = 0; i <= (j - k); ++i) { 264 int k2 = compare_part(exit_alt_charset_mode, off + i); 265 if (k2 != 0) { 266 found = TRUE; 267 chop_out(off, i, i + k2); 268 break; 269 } 270 } 271 } 272 } 273 /* 274 * SGR 10 would reset to normal font. 275 */ 276 if (!found) { 277 if ((i = is_csi(off)) != 0 278 && off[strlen(off) - 1] == 'm') { 279 TR(TRACE_DATABASE, ("looking for SGR 10 in %s", 280 _nc_visbuf(off))); 281 tmp = skip_zero(off + i); 282 if (tmp[0] == '1' 283 && skip_zero(tmp + 1) != tmp + 1) { 284 i = tmp - off; 285 if (off[i - 1] == ';') 286 i--; 287 j = skip_zero(tmp + 1) - off; 288 i = chop_out(off, i, j); 289 found = TRUE; 290 } 291 } 292 } 293 if (!found 294 && (tmp = strstr(end, off)) != 0 295 && strcmp(end, off) != 0) { 296 i = tmp - end; 297 j = strlen(off); 298 tmp = strdup(end); 299 chop_out(tmp, i, j); 300 free(off); 301 result = tmp; 302 } 303 TR(TRACE_DATABASE, ("...adjusted sgr0 : %s", _nc_visbuf(result))); 304 if (!strcmp(result, exit_attribute_mode)) { 305 TR(TRACE_DATABASE, ("...same result, discard")); 306 free(result); 307 result = exit_attribute_mode; 308 } 309 } else { 310 /* 311 * Either the sgr does not reference alternate character set, 312 * or it is incorrect. That's too hard to decide right now. 313 */ 314 free(off); 315 } 316 FreeIfNeeded(end); 317 FreeIfNeeded(on); 318 } else { 319 /* 320 * Possibly some applications are confused if sgr0 contains rmacs, 321 * but that would be a different bug report -TD 322 */ 323 } 324 325 returnPtr(result); 326 } 327