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