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/*
* Copyright 2007 Jon Loeliger, Freescale Semiconductor, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*/
#include "srcpos.h"
/*
* This code should only be included into the lexical analysis.
* It references global context symbols that are only present
* in the generated lex.yy,c file.
*/
#ifdef FLEX_SCANNER
/*
* Stack of nested include file contexts.
*/
struct incl_file {
int filenum;
FILE *file;
YY_BUFFER_STATE yy_prev_buf;
int yy_prev_lineno;
struct incl_file *prev;
};
struct incl_file *incl_file_stack;
/*
* Detect infinite include recursion.
*/
#define MAX_INCLUDE_DEPTH (100)
static int incl_depth = 0;
int push_input_file(const char *filename)
{
FILE *f;
struct incl_file *incl_file;
if (!filename) {
yyerror("No include file name given.");
return 0;
}
if (incl_depth++ >= MAX_INCLUDE_DEPTH) {
yyerror("Includes nested too deeply");
return 0;
}
f = dtc_open_file(filename);
incl_file = malloc(sizeof(struct incl_file));
if (!incl_file) {
yyerror("Can not allocate include file space.");
return 0;
}
/*
* Save current context.
*/
incl_file->yy_prev_buf = YY_CURRENT_BUFFER;
incl_file->yy_prev_lineno = yylineno;
incl_file->filenum = srcpos_filenum;
incl_file->file = yyin;
incl_file->prev = incl_file_stack;
incl_file_stack = incl_file;
/*
* Establish new context.
*/
srcpos_filenum = lookup_file_name(filename, 0);
yylineno = 1;
yyin = f;
yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));
return 1;
}
int pop_input_file(void)
{
struct incl_file *incl_file;
if (incl_file_stack == 0)
return 0;
fclose(yyin);
/*
* Pop.
*/
--incl_depth;
incl_file = incl_file_stack;
incl_file_stack = incl_file->prev;
/*
* Recover old context.
*/
yy_delete_buffer(YY_CURRENT_BUFFER);
yy_switch_to_buffer(incl_file->yy_prev_buf);
yylineno = incl_file->yy_prev_lineno;
srcpos_filenum = incl_file->filenum;
yyin = incl_file->file;
/*
* Free old state.
*/
free(incl_file);
if (YY_CURRENT_BUFFER == 0)
return 0;
return 1;
}
#endif /* FLEX_SCANNER */
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