util/kconfig/lexer.l

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
   4  */
   5 %option nostdinit noyywrap never-interactive full ecs
   6 %option 8bit nodefault yylineno
   7 %x ASSIGN_VAL HELP STRING
   8 %{
   9
  10 #include <assert.h>
  11 #include <glob.h>
  12 #include <limits.h>
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16
  17 #include "lkc.h"
  18 #include "parser.tab.h"
  19
  20 #define YY_DECL         static int yylex1(void)
  21
  22 #define START_STRSIZE   16
  23
  24 static struct {
  25         struct file *file;
  26         int lineno;
  27 } current_pos;
  28
  29 static int prev_prev_token = T_EOL;
  30 static int prev_token = T_EOL;
  31 static char *text;
  32 static int text_size, text_asize;
  33
  34 struct buffer {
  35         struct buffer *parent;
  36         YY_BUFFER_STATE state;
  37 };
  38
  39 static struct buffer *current_buf;
  40
  41 static int last_ts, first_ts;
  42
  43 static char *expand_token(const char *in, size_t n);
  44 static void append_expanded_string(const char *in);
  45 static void zconf_endhelp(void);
  46 static void zconf_endfile(void);
  47
  48 static void new_string(void)
  49 {
  50         text = xmalloc(START_STRSIZE);
  51         text_asize = START_STRSIZE;
  52         text_size = 0;
  53         *text = 0;
  54 }
  55
  56 static void append_string(const char *str, int size)
  57 {
  58         int new_size = text_size + size + 1;
  59         if (new_size > text_asize) {
  60                 new_size += START_STRSIZE - 1;
  61                 new_size &= -START_STRSIZE;
  62                 text = xrealloc(text, new_size);
  63                 text_asize = new_size;
  64         }
  65         memcpy(text + text_size, str, size);
  66         text_size += size;
  67         text[text_size] = 0;
  68 }
  69
  70 static void alloc_string(const char *str, int size)
  71 {
  72         text = xmalloc(size + 1);
  73         memcpy(text, str, size);
  74         text[size] = 0;
  75 }
  76
  77 static void warn_ignored_character(char chr)
  78 {
  79         fprintf(stderr,
  80                 "%s:%d:warning: ignoring unsupported character '%c'\n",
  81                 current_file->name, yylineno, chr);
  82 }
  83 %}
  84
  85 n       [A-Za-z0-9_-]
  86
  87 %%
  88         char open_quote = 0;
  89
  90 #.*                     /* ignore comment */
  91 [ \t]*                  /* whitespaces */
  92 \\\n                    /* escaped new line */
  93 \n                      return T_EOL;
  94 "bool"                  return T_BOOL;
  95 "choice"                return T_CHOICE;
  96 "comment"               return T_COMMENT;
  97 "config"                return T_CONFIG;
  98 "def_bool"              return T_DEF_BOOL;
  99 "def_tristate"          return T_DEF_TRISTATE;
 100 "default"               return T_DEFAULT;
 101 "depends"               return T_DEPENDS;
 102 "endchoice"             return T_ENDCHOICE;
 103 "endif"                 return T_ENDIF;
 104 "endmenu"               return T_ENDMENU;
 105 "help"                  return T_HELP;
 106 "hex"                   return T_HEX;
 107 "if"                    return T_IF;
 108 "imply"                 return T_IMPLY;
 109 "int"                   return T_INT;
 110 "mainmenu"              return T_MAINMENU;
 111 "menu"                  return T_MENU;
 112 "menuconfig"            return T_MENUCONFIG;
 113 "modules"               return T_MODULES;
 114 "on"                    return T_ON;
 115 "optional"              return T_OPTIONAL;
 116 "prompt"                return T_PROMPT;
 117 "range"                 return T_RANGE;
 118 "select"                return T_SELECT;
 119 "source"                return T_SOURCE;
 120 "string"                return T_STRING;
 121 "tristate"              return T_TRISTATE;
 122 "visible"               return T_VISIBLE;
 123 "||"                    return T_OR;
 124 "&&"                    return T_AND;
 125 "="                     return T_EQUAL;
 126 "!="                    return T_UNEQUAL;
 127 "<"                     return T_LESS;
 128 "<="                    return T_LESS_EQUAL;
 129 ">"                     return T_GREATER;
 130 ">="                    return T_GREATER_EQUAL;
 131 "!"                     return T_NOT;
 132 "("                     return T_OPEN_PAREN;
 133 ")"                     return T_CLOSE_PAREN;
 134 ":="                    return T_COLON_EQUAL;
 135 "+="                    return T_PLUS_EQUAL;
 136 \"|\'                   {
 137                                 open_quote = yytext[0];
 138                                 new_string();
 139                                 BEGIN(STRING);
 140                         }
 141 {n}+                    {
 142                                 alloc_string(yytext, yyleng);
 143                                 yylval.string = text;
 144                                 return T_WORD;
 145                         }
 146 ({n}|$)+                {
 147                                 /* this token includes at least one '$' */
 148                                 yylval.string = expand_token(yytext, yyleng);
 149                                 if (strlen(yylval.string))
 150                                         return T_WORD;
 151                                 free(yylval.string);
 152                         }
 153 .                       warn_ignored_character(*yytext);
 154
 155 <ASSIGN_VAL>{
 156         [^[:blank:]\n]+.*       {
 157                 alloc_string(yytext, yyleng);
 158                 yylval.string = text;
 159                 return T_ASSIGN_VAL;
 160         }
 161         \n      { BEGIN(INITIAL); return T_EOL; }
 162         .
 163 }
 164
 165 <STRING>{
 166         "$".*   append_expanded_string(yytext);
 167         [^$'"\\\n]+     {
 168                 append_string(yytext, yyleng);
 169         }
 170         \\.?    {
 171                 append_string(yytext + 1, yyleng - 1);
 172         }
 173         \'|\"   {
 174                 if (open_quote == yytext[0]) {
 175                         BEGIN(INITIAL);
 176                         yylval.string = text;
 177                         return T_WORD_QUOTE;
 178                 } else
 179                         append_string(yytext, 1);
 180         }
 181         \n      {
 182                 fprintf(stderr,
 183                         "%s:%d:warning: multi-line strings not supported\n",
 184                         zconf_curname(), zconf_lineno());
 185                 unput('\n');
 186                 BEGIN(INITIAL);
 187                 yylval.string = text;
 188                 return T_WORD_QUOTE;
 189         }
 190         <<EOF>> {
 191                 BEGIN(INITIAL);
 192                 yylval.string = text;
 193                 return T_WORD_QUOTE;
 194         }
 195 }
 196
 197 <HELP>{
 198         [ \t]+  {
 199                 int ts, i;
 200
 201                 ts = 0;
 202                 for (i = 0; i < yyleng; i++) {
 203                         if (yytext[i] == '\t')
 204                                 ts = (ts & ~7) + 8;
 205                         else
 206                                 ts++;
 207                 }
 208                 last_ts = ts;
 209                 if (first_ts) {
 210                         if (ts < first_ts) {
 211                                 zconf_endhelp();
 212                                 return T_HELPTEXT;
 213                         }
 214                         ts -= first_ts;
 215                         while (ts > 8) {
 216                                 append_string("        ", 8);
 217                                 ts -= 8;
 218                         }
 219                         append_string("        ", ts);
 220                 }
 221         }
 222         [ \t]*\n/[^ \t\n] {
 223                 zconf_endhelp();
 224                 return T_HELPTEXT;
 225         }
 226         [ \t]*\n        {
 227                 append_string("\n", 1);
 228         }
 229         [^ \t\n].* {
 230                 while (yyleng) {
 231                         if ((yytext[yyleng-1] != ' ') && (yytext[yyleng-1] != '\t'))
 232                                 break;
 233                         yyleng--;
 234                 }
 235                 append_string(yytext, yyleng);
 236                 if (!first_ts)
 237                         first_ts = last_ts;
 238         }
 239         <<EOF>> {
 240                 zconf_endhelp();
 241                 return T_HELPTEXT;
 242         }
 243 }
 244
 245 <<EOF>> {
 246         BEGIN(INITIAL);
 247
 248         if (prev_token != T_EOL && prev_token != T_HELPTEXT)
 249                 fprintf(stderr, "%s:%d:warning: no new line at end of file\n",
 250                         current_file->name, yylineno);
 251
 252         if (current_file) {
 253                 zconf_endfile();
 254                 return T_EOL;
 255         }
 256         fclose(yyin);
 257         yyterminate();
 258 }
 259
 260 %%
 261
 262 /* second stage lexer */
 263 int yylex(void)
 264 {
 265         int token;
 266
 267 repeat:
 268         token = yylex1();
 269
 270         if (prev_token == T_EOL || prev_token == T_HELPTEXT) {
 271                 if (token == T_EOL) {
 272                         /* Do not pass unneeded T_EOL to the parser. */
 273                         goto repeat;
 274                 } else {
 275                         /*
 276                          * For the parser, update file/lineno at the first token
 277                          * of each statement. Generally, \n is a statement
 278                          * terminator in Kconfig, but it is not always true
 279                          * because \n could be escaped by a backslash.
 280                          */
 281                         current_pos.file = current_file;
 282                         current_pos.lineno = yylineno;
 283                 }
 284         }
 285
 286         if (prev_prev_token == T_EOL && prev_token == T_WORD &&
 287             (token == T_EQUAL || token == T_COLON_EQUAL || token == T_PLUS_EQUAL))
 288                 BEGIN(ASSIGN_VAL);
 289
 290         prev_prev_token = prev_token;
 291         prev_token = token;
 292
 293         return token;
 294 }
 295
 296 static char *expand_token(const char *in, size_t n)
 297 {
 298         char *out;
 299         int c;
 300         char c2;
 301         const char *rest, *end;
 302
 303         new_string();
 304         append_string(in, n);
 305
 306         /* get the whole line because we do not know the end of token. */
 307         while ((c = input()) != EOF) {
 308                 if (c == '\n') {
 309                         unput(c);
 310                         break;
 311                 }
 312                 c2 = c;
 313                 append_string(&c2, 1);
 314         }
 315
 316         rest = text;
 317         out = expand_one_token(&rest);
 318
 319         /* push back unused characters to the input stream */
 320         end = rest + strlen(rest);
 321         while (end > rest)
 322                 unput(*--end);
 323
 324         free(text);
 325
 326         return out;
 327 }
 328
 329 static void append_expanded_string(const char *str)
 330 {
 331         const char *end;
 332         char *res;
 333
 334         str++;
 335
 336         res = expand_dollar(&str);
 337
 338         /* push back unused characters to the input stream */
 339         end = str + strlen(str);
 340         while (end > str)
 341                 unput(*--end);
 342
 343         append_string(res, strlen(res));
 344
 345         free(res);
 346 }
 347
 348 void zconf_starthelp(void)
 349 {
 350         new_string();
 351         last_ts = first_ts = 0;
 352         BEGIN(HELP);
 353 }
 354
 355 static void zconf_endhelp(void)
 356 {
 357         yylval.string = text;
 358         BEGIN(INITIAL);
 359 }
 360
 361
 362 /*
 363  * Try to open specified file with following names:
 364  * ./name
 365  * $(srctree)/name
 366  * The latter is used when srctree is separate from objtree
 367  * when compiling the kernel.
 368  * Return NULL if file is not found.
 369  */
 370 FILE *zconf_fopen(const char *name)
 371 {
 372         char *env, fullname[PATH_MAX+1];
 373         FILE *f;
 374
 375         f = fopen(name, "r");
 376         if (!f && name != NULL && name[0] != '/') {
 377                 env = getenv(SRCTREE);
 378                 if (env) {
 379                         snprintf(fullname, sizeof(fullname),
 380                                  "%s/%s", env, name);
 381                         f = fopen(fullname, "r");
 382                 }
 383         }
 384         return f;
 385 }
 386
 387 void zconf_initscan(const char *name)
 388 {
 389         yyin = zconf_fopen(name);
 390         if (!yyin) {
 391                 fprintf(stderr, "can't find file %s\n", name);
 392                 exit(1);
 393         }
 394
 395         current_buf = xmalloc(sizeof(*current_buf));
 396         memset(current_buf, 0, sizeof(*current_buf));
 397
 398         current_file = file_lookup(name);
 399         yylineno = 1;
 400 }
 401
 402 void zconf_nextfile(const char *name)
 403 {
 404         struct file *iter;
 405         struct file *file = file_lookup(name);
 406         struct buffer *buf = xmalloc(sizeof(*buf));
 407         memset(buf, 0, sizeof(*buf));
 408
 409         current_buf->state = YY_CURRENT_BUFFER;
 410         yyin = zconf_fopen(file->name);
 411         if (!yyin) {
 412                 fprintf(stderr, "%s:%d: can't open file \"%s\"\n",
 413                         zconf_curname(), zconf_lineno(), file->name);
 414                 exit(1);
 415         }
 416         yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));
 417         buf->parent = current_buf;
 418         current_buf = buf;
 419
 420         current_file->lineno = yylineno;
 421         file->parent = current_file;
 422
 423         for (iter = current_file; iter; iter = iter->parent) {
 424                 if (!strcmp(iter->name, file->name)) {
 425                         fprintf(stderr,
 426                                 "Recursive inclusion detected.\n"
 427                                 "Inclusion path:\n"
 428                                 "  current file : %s\n", file->name);
 429                         iter = file;
 430                         do {
 431                                 iter = iter->parent;
 432                                 fprintf(stderr, "  included from: %s:%d\n",
 433                                         iter->name, iter->lineno - 1);
 434                         } while (strcmp(iter->name, file->name));
 435                         exit(1);
 436                 }
 437         }
 438
 439         yylineno = 1;
 440         current_file = file;
 441 }
 442
 443 void zconf_nextfiles(const char *wildcard)
 444 {
 445         glob_t g;
 446         char **w;
 447         int i;
 448
 449         if (glob(wildcard, 0, NULL, &g) != 0) {
 450                 return;
 451         }
 452         if (g.gl_pathv == NULL) {
 453                 globfree(&g);
 454                 return;
 455         }
 456
 457         /* working through files backwards, since
 458          * we're first pushing them on a stack
 459          * before actually handling them.
 460          */
 461         for (i = g.gl_pathc; i > 0; i--) {
 462                 w = &g.gl_pathv[i - 1];
 463                 zconf_nextfile(*w);
 464         }
 465
 466         globfree(&g);
 467 }
 468
 469 static void zconf_endfile(void)
 470 {
 471         struct buffer *parent;
 472
 473         current_file = current_file->parent;
 474         if (current_file)
 475                 yylineno = current_file->lineno;
 476
 477         parent = current_buf->parent;
 478         if (parent) {
 479                 fclose(yyin);
 480                 yy_delete_buffer(YY_CURRENT_BUFFER);
 481                 yy_switch_to_buffer(parent->state);
 482         }
 483         free(current_buf);
 484         current_buf = parent;
 485 }
 486
 487 int zconf_lineno(void)
 488 {
 489         return current_pos.lineno;
 490 }
 491
 492 const char *zconf_curname(void)
 493 {
 494         return current_pos.file ? current_pos.file->name : "<none>";
 495 }