source: drbl_ui/backup/test_busybox/busybox-1.7.2/scripts/kconfig/zconf.l @ 20

%option backup nostdinit noyywrap never-interactive full ecs
%option 8bit backup nodefault perf-report perf-report
%x COMMAND HELP STRING PARAM
%{
/*
 * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
 * Released under the terms of the GNU GPL v2.0.
 */

#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#define LKC_DIRECT_LINK
#include "lkc.h"

#define START_STRSIZE 16

static struct {
  struct file *file;
  int lineno;
} current_pos;

static char *text;
static int text_size, text_asize;

struct buffer {
        struct buffer *parent;
        YY_BUFFER_STATE state;
};

struct buffer *current_buf;

static int last_ts, first_ts;

static void zconf_endhelp(void);
static void zconf_endfile(void);

void new_string(void)
{
  text = malloc(START_STRSIZE);
  text_asize = START_STRSIZE;
  text_size = 0;
  *text = 0;
}

void append_string(const char *str, int size)
{
  int new_size = text_size + size + 1;
  if (new_size > text_asize) {
    new_size += START_STRSIZE - 1;
    new_size &= -START_STRSIZE;
    text = realloc(text, new_size);
    text_asize = new_size;
  }
  memcpy(text + text_size, str, size);
  text_size += size;
  text[text_size] = 0;
}

void alloc_string(const char *str, int size)
{
  text = malloc(size + 1);
  memcpy(text, str, size);
  text[size] = 0;
}
%}

ws  [ \n\t]
n [A-Za-z0-9_]

%%
  int str = 0;
  int ts, i;

[ \t]*#.*\n |
[ \t]*\n  {
  current_file->lineno++;
  return T_EOL;
}
[ \t]*#.*


[ \t]+  {
  BEGIN(COMMAND);
}

. {
  unput(yytext[0]);
  BEGIN(COMMAND);
}


<COMMAND>{
  {n}+  {
    struct kconf_id *id = kconf_id_lookup(yytext, yyleng);
    BEGIN(PARAM);
    current_pos.file = current_file;
    current_pos.lineno = current_file->lineno;
    if (id && id->flags & TF_COMMAND) {
      zconflval.id = id;
      return id->token;
    }
    alloc_string(yytext, yyleng);
    zconflval.string = text;
    return T_WORD;
  }
  .
  \n  {
    BEGIN(INITIAL);
    current_file->lineno++;
    return T_EOL;
  }
}

<PARAM>{
  "&&"  return T_AND;
  "||"  return T_OR;
  "(" return T_OPEN_PAREN;
  ")" return T_CLOSE_PAREN;
  "!" return T_NOT;
  "=" return T_EQUAL;
  "!="  return T_UNEQUAL;
  \"|\' {
    str = yytext[0];
    new_string();
    BEGIN(STRING);
  }
  \n  BEGIN(INITIAL); current_file->lineno++; return T_EOL;
  --- /* ignore */
  ({n}|[-/.])+  {
    struct kconf_id *id = kconf_id_lookup(yytext, yyleng);
    if (id && id->flags & TF_PARAM) {
      zconflval.id = id;
      return id->token;
    }
    alloc_string(yytext, yyleng);
    zconflval.string = text;
    return T_WORD;
  }
  #.* /* comment */
  \\\n  current_file->lineno++;
  .
  <<EOF>> {
    BEGIN(INITIAL);
  }
}

<STRING>{
  [^'"\\\n]+/\n {
    append_string(yytext, yyleng);
    zconflval.string = text;
    return T_WORD_QUOTE;
  }
  [^'"\\\n]+  {
    append_string(yytext, yyleng);
  }
  \\.?/\n {
    append_string(yytext + 1, yyleng - 1);
    zconflval.string = text;
    return T_WORD_QUOTE;
  }
  \\.?  {
    append_string(yytext + 1, yyleng - 1);
  }
  \'|\" {
    if (str == yytext[0]) {
      BEGIN(PARAM);
      zconflval.string = text;
      return T_WORD_QUOTE;
    } else
      append_string(yytext, 1);
  }
  \n  {
    printf("%s:%d:warning: multi-line strings not supported\n", zconf_curname(), zconf_lineno());
    current_file->lineno++;
    BEGIN(INITIAL);
    return T_EOL;
  }
  <<EOF>> {
    BEGIN(INITIAL);
  }
}

<HELP>{
  [ \t]+  {
    ts = 0;
    for (i = 0; i < yyleng; i++) {
      if (yytext[i] == '\t')
        ts = (ts & ~7) + 8;
      else
        ts++;
    }
    last_ts = ts;
    if (first_ts) {
      if (ts < first_ts) {
        zconf_endhelp();
        return T_HELPTEXT;
      }
      ts -= first_ts;
      while (ts > 8) {
        append_string("        ", 8);
        ts -= 8;
      }
      append_string("        ", ts);
    }
  }
  [ \t]*\n/[^ \t\n] {
    current_file->lineno++;
    zconf_endhelp();
    return T_HELPTEXT;
  }
  [ \t]*\n  {
    current_file->lineno++;
    append_string("\n", 1);
  }
  [^ \t\n].* {
    append_string(yytext, yyleng);
    if (!first_ts)
      first_ts = last_ts;
  }
  <<EOF>> {
    zconf_endhelp();
    return T_HELPTEXT;
  }
}

<<EOF>> {
  if (current_file) {
    zconf_endfile();
    return T_EOL;
  }
  fclose(yyin);
  yyterminate();
}

%%
void zconf_starthelp(void)
{
  new_string();
  last_ts = first_ts = 0;
  BEGIN(HELP);
}

static void zconf_endhelp(void)
{
  zconflval.string = text;
  BEGIN(INITIAL);
}


/*
 * Try to open specified file with following names:
 * ./name
 * $(srctree)/name
 * The latter is used when srctree is separate from objtree
 * when compiling the kernel.
 * Return NULL if file is not found.
 */
FILE *zconf_fopen(const char *name)
{
  char *env, fullname[PATH_MAX+1];
  FILE *f;

  f = fopen(name, "r");
  if (!f && name[0] != '/') {
    env = getenv(SRCTREE);
    if (env) {
      sprintf(fullname, "%s/%s", env, name);
      f = fopen(fullname, "r");
    }
  }
  return f;
}

void zconf_initscan(const char *name)
{
  yyin = zconf_fopen(name);
  if (!yyin) {
    printf("can't find file %s\n", name);
    exit(1);
  }

  current_buf = malloc(sizeof(*current_buf));
  memset(current_buf, 0, sizeof(*current_buf));

  current_file = file_lookup(name);
  current_file->lineno = 1;
  current_file->flags = FILE_BUSY;
}

void zconf_nextfile(const char *name)
{
  struct file *file = file_lookup(name);
  struct buffer *buf = malloc(sizeof(*buf));
  memset(buf, 0, sizeof(*buf));

  current_buf->state = YY_CURRENT_BUFFER;
  yyin = zconf_fopen(name);
  if (!yyin) {
    printf("%s:%d: can't open file \"%s\"\n", zconf_curname(), zconf_lineno(), name);
    exit(1);
  }
  yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));
  buf->parent = current_buf;
  current_buf = buf;

  if (file->flags & FILE_BUSY) {
    printf("recursive scan (%s)?\n", name);
    exit(1);
  }
  if (file->flags & FILE_SCANNED) {
    printf("file %s already scanned?\n", name);
    exit(1);
  }
  file->flags |= FILE_BUSY;
  file->lineno = 1;
  file->parent = current_file;
  current_file = file;
}

static void zconf_endfile(void)
{
  struct buffer *parent;

  current_file->flags |= FILE_SCANNED;
  current_file->flags &= ~FILE_BUSY;
  current_file = current_file->parent;

  parent = current_buf->parent;
  if (parent) {
    fclose(yyin);
    yy_delete_buffer(YY_CURRENT_BUFFER);
    yy_switch_to_buffer(parent->state);
  }
  free(current_buf);
  current_buf = parent;
}

int zconf_lineno(void)
{
  return current_pos.lineno;
}

char *zconf_curname(void)
{
  return current_pos.file ? current_pos.file->name : "<none>";
}