cfg.c

LINUX lilo-22.7 源代码。

/* cfg.c  -  Configuration file parser */
/*
Copyright 1992-1997 Werner Almesberger.
Copyright 1999-2004 John Coffman.
All rights reserved.

Licensed under the terms contained in the file 'COPYING' in the 
source directory.

*/


#define _GNU_SOURCE
#include <sys/stat.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <stdarg.h>
#include <ctype.h>
#include <string.h>

#include "lilo.h"
#include "common.h"
#include "temp.h"
#include "cfg.h"

#define NEW_PARSE !__MSDOS__

#define MAX_VAR_NAME MAX_TOKEN

#if !__MSDOS__
extern void do_image(void);
extern void do_other(void);
extern void do_disk(void);
extern void do_partition(void);

extern void id_image(void);
extern void id_other(void);

extern void do_map_drive(void);
extern void do_cr(void);
extern void do_change(void);
extern void do_cr_type(void);
extern void do_cr_reset(void);
extern void do_cr_part(void);
extern void do_cr_auto(void);


CONFIG cf_top[] = {
  { cft_strg, "image",		do_image,	NULL,NULL },
  { cft_strg, "other",		do_other,	NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};

CONFIG cf_identify[] = {
  { cft_strg, "image",		id_image,	NULL,NULL },
  { cft_strg, "other",		id_other,	NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};
#endif /* !__MSDOS__ */

CONFIG cf_options[] = {
#if !__MSDOS__
  { cft_strg, "append",		NULL,		NULL,NULL },
/*#ifdef LCF_ATARAID*/
#if 0
  { cft_flag, "ataraid",	NULL,		NULL,NULL },
#endif
  { cft_strg, "backup",		NULL,		NULL,NULL },
  { cft_strg, "bios-passes-dl",	NULL,		NULL,NULL },
  { cft_strg, "bitmap",		NULL,		NULL,NULL },
  { cft_strg, "bmp-colors",	NULL,		NULL,NULL },
  { cft_flag, "bmp-retain",	NULL,		NULL,NULL },
  { cft_strg, "bmp-table",	NULL,		NULL,NULL },
  { cft_strg, "bmp-timer",	NULL,		NULL,NULL },
  { cft_strg, "boot",		NULL,		NULL,NULL },
  { cft_strg, "boot-as",	NULL,		NULL,NULL },
  { cft_flag, "change-rules",	do_cr,		NULL,NULL },
  { cft_flag, "compact",	NULL,		NULL,NULL },
  { cft_strg, "default",	NULL,		NULL,NULL },
  { cft_strg, "delay",		NULL,		NULL,NULL },
  { cft_strg, "disk",		do_disk,	NULL,NULL },
  { cft_strg, "disktab",	NULL,		NULL,NULL },
  { cft_flag, "el-torito-bootable-cd",	NULL,		NULL,NULL },
  { cft_strg, "fallback",	NULL,		NULL,NULL },
  { cft_flag, "fix-table",     	NULL,		NULL,NULL },
  { cft_strg, "force-backup",	NULL,		NULL,NULL },
  { cft_flag, "geometric",      NULL,           NULL,NULL }, 
  { cft_flag, "ignore-table",   NULL,		NULL,NULL },
  { cft_strg, "initrd",		NULL,		NULL,NULL },
  { cft_strg, "install",	NULL,		NULL,NULL },
  { cft_strg, "keytable",	NULL,		NULL,NULL },
  { cft_flag, "large-memory",	NULL,		NULL,NULL },
  { cft_flag, "lba32",          NULL,           NULL,NULL }, 
  { cft_flag, "linear",     	NULL,		NULL,NULL },
  { cft_strg, "loader",		NULL,		NULL,NULL },
  { cft_flag, "lock",		NULL,		NULL,NULL },
  { cft_flag, "mandatory",	NULL,		NULL,NULL },
#endif /* !__MSDOS__ */
  { cft_strg, "map",		NULL,		NULL,NULL },
#if !__MSDOS__
  { cft_flag, "master-boot",	NULL,		NULL,NULL },
  { cft_strg, "menu-scheme",	NULL,		NULL,NULL },
  { cft_strg, "menu-title",	NULL,		NULL,NULL },
  { cft_strg, "message",	NULL,		NULL,NULL },
  { cft_flag, "nowarn",		NULL,		NULL,NULL },
  { cft_flag, "optional",	NULL,		NULL,NULL },
  { cft_strg, "password",	NULL,		NULL,NULL },
  { cft_flag, "prompt",		NULL,		NULL,NULL },
  { cft_strg, RAID_EXTRA_BOOT,	NULL,		NULL,NULL },
  { cft_strg, "ramdisk",	NULL,		NULL,NULL },
  { cft_flag, "read-only",	NULL,		NULL,NULL },
  { cft_flag, "read-write",	NULL,		NULL,NULL },
  { cft_flag, "restricted",	NULL,		NULL,NULL },
  { cft_strg, "root",		NULL,		NULL,NULL },
  { cft_strg, "serial",		NULL,		NULL,NULL },
  { cft_flag, "single-key",	NULL,		NULL,NULL },
  { cft_flag, "static-bios-codes",	NULL,		NULL,NULL },
  { cft_flag, "suppress-boot-time-BIOS-data",	NULL,	NULL,NULL },
  { cft_strg, "timeout",	NULL,		NULL,NULL },
  { cft_flag, "unattended",	NULL,		NULL,NULL },
  { cft_strg, "verbose",	NULL,		NULL,NULL },
  { cft_strg, "vga",		NULL,		NULL,NULL },
  { cft_strg, "vmdefault",	NULL,		NULL,NULL },
#endif /* !__MSDOS__ */
  { cft_end,  NULL,		NULL,		NULL,NULL }};

#if !__MSDOS__
CONFIG cf_all[] = {
  { cft_strg, "alias",		NULL,		NULL,NULL },
  { cft_flag, "bmp-retain",	NULL,		NULL,NULL },
  { cft_flag, "bypass",		NULL,		NULL,NULL },
  { cft_strg, "fallback",	NULL,		NULL,NULL },
  { cft_strg, "label",		NULL,		NULL,NULL },
  { cft_strg, "literal",	NULL,		NULL,NULL },
  { cft_flag, "lock",		NULL,		NULL,NULL },
  { cft_flag, "mandatory",	NULL,		NULL,NULL },
  { cft_flag, "optional",	NULL,		NULL,NULL },
  { cft_strg, "password",	NULL,		NULL,NULL },
  { cft_flag, "restricted",	NULL,		NULL,NULL },
  { cft_flag, "single-key",	NULL,		NULL,NULL },
  { cft_flag, "vmdisable",	NULL,		NULL,NULL },
  { cft_flag, "vmwarn",		NULL,		NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};

CONFIG cf_kernel[] = {
  { cft_strg, "addappend",	NULL,		NULL,NULL },
  { cft_strg, "append",		NULL,		NULL,NULL },
  { cft_strg, "initrd",		NULL,		NULL,NULL },
  { cft_strg, "ramdisk",	NULL,		NULL,NULL },
  { cft_flag, "read-only",	NULL,		NULL,NULL },
  { cft_flag, "read-write",	NULL,		NULL,NULL },
  { cft_strg, "root",		NULL,		NULL,NULL },
  { cft_strg, "vga",		NULL,		NULL,NULL },
  { cft_link, NULL,		&cf_all,	NULL,NULL }};

CONFIG cf_image[] = {
  { cft_strg, "range",		NULL,		NULL,NULL },
  { cft_link, NULL,		&cf_kernel,	NULL,NULL }};

CONFIG cf_other[] = {
  { cft_strg, "boot-as",	NULL,		NULL,NULL },
  { cft_flag, "change",		do_change,	NULL,NULL },
  { cft_strg, "loader",		NULL,		NULL,NULL },
  { cft_strg, "map-drive",	do_map_drive,	NULL,NULL },
  { cft_flag, "master-boot",	NULL,		NULL,NULL },
  { cft_strg, "table",		NULL,		NULL,NULL },
  { cft_flag, "unsafe",		NULL,		NULL,NULL },
  { cft_link, NULL,		&cf_all,	NULL,NULL }};

CONFIG cf_disk[] = {
  { cft_strg, "bios",		NULL,		NULL,NULL },
  { cft_strg, "cylinders",	NULL,		NULL,NULL },
  { cft_strg, "heads",		NULL,		NULL,NULL },
  { cft_flag, "inaccessible",	NULL,		NULL,NULL },
  { cft_strg, "max-partitions",	NULL,		NULL,NULL },
  { cft_strg, "sectors",	NULL,		NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};

CONFIG cf_partitions[] = {
  { cft_strg, "partition",	do_partition,	NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};

CONFIG cf_partition[] = {
  { cft_strg, "start",		NULL,		NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};

CONFIG cf_map_drive[] = {
  { cft_strg, "to",		NULL,		NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};

CONFIG cf_change_rules[] = {
  { cft_flag, "reset",		do_cr_reset,	NULL,NULL },
  { cft_strg, "type",		do_cr_type,	NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};

CONFIG cf_change_rule[] = {
  { cft_strg, "hidden",		NULL,		NULL,NULL },
  { cft_strg, "normal",		NULL,		NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};

CONFIG cf_change[] = {
  { cft_flag, "automatic",	do_cr_auto,	NULL,NULL },
  { cft_strg, "partition",	do_cr_part,	NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};

CONFIG cf_change_dsc[] = {
  { cft_flag, "activate",	NULL,		NULL,NULL },
  { cft_flag, "deactivate",	NULL,		NULL,NULL },
  { cft_strg, "set",		NULL,		NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};

CONFIG cf_bitmap[] = {
  { cft_strg, "bitmap",		NULL,		NULL,NULL },
  { cft_strg, "bmp-colors",	NULL,		NULL,NULL },
  { cft_strg, "bmp-table",	NULL,		NULL,NULL },
  { cft_strg, "bmp-timer",	NULL,		NULL,NULL },
  { cft_end,  NULL,		NULL,		NULL,NULL }};
#endif /* !__MSDOS__ */

#if NEW_PARSE

static CONFIG *keywords[] = {cf_top, cf_identify, cf_options, cf_all,
	cf_kernel, cf_image, cf_other, cf_disk, cf_partitions, cf_partition,
	cf_map_drive, cf_change_rules, cf_change_rule, cf_change, 
	cf_change_dsc, cf_bitmap, NULL };

#endif
	
static FILE *file;
static char flag_set;
static char *last_token = NULL,*last_item = NULL,*last_value = NULL;
static int line_num;
static char *file_name = NULL;
static int back = 0; /* can go back by one char */


int cfg_open(char *name)
{
    line_num = 1;
    if (!strcmp(name,"-")) file = stdin;

#if __MSDOS__
    else if (!strcasecmp(name,"none")) return -1;
#endif /* __MSDOS__ */

    else if (!(file = fopen(file_name = name,"r"))) {
#if !__MSDOS__
		die("Cannot open: %s", name);
#else  /* __MSDOS__ */
		fprintf(errstd,"No configuration file: %s\n", name);
		return -1;
#endif /* __MSDOS__ */
    }

    return fileno(file);
}


void cfg_error(char *msg,...)
{
    va_list ap;

    fflush(stdout);
    va_start(ap,msg);
    vfprintf(errstd,msg,ap);
    va_end(ap);
    if (!file_name) fputc('\n',errstd);
    else fprintf(errstd," at or above line %d in file '%s'\n",line_num,file_name);
    exit(1);
}


static int next_raw(void)
{
    int ch;

    if (!back) return getc(file);
    ch = back;
    back = 0;
    return ch;
}


static int next(void)
{
    static char *var;
    char buffer[MAX_VAR_NAME+1];
    int ch,braced;
    char *put;

    if (back) {
	ch = back;
	back = 0;
	return ch;
    }
    if (var && *var) return *var++;
    ch = getc(file);
    if (ch == '\r')		/* strip DOS <cr> */
        ch = getc(file);
    if (ch == '\\') {
	ch = getc(file);
	if (ch == '$') return ch;
	ungetc(ch,file);
	return '\\';
    }
    if (ch != '$') return ch;
    ch = getc(file);
    braced = ch == '{';
    put = buffer;
    if (!braced) *put++ = ch;
    while (1) {
	ch = getc(file);
#if 0
	if (!braced && ch < ' ') {
	    ungetc(ch,file);
	    break;
	}
#endif
	if (ch == EOF) cfg_error("EOF in variable name");
	if (ch < ' ') cfg_error("control character in variable name");
	if (braced && ch == '}') break;
	if (!braced && !isalpha(ch) && !isdigit(ch) && ch != '_') {
	    ungetc(ch,file);
	    break;
	}
	if (put-buffer == MAX_VAR_NAME) cfg_error("variable name too long");
	*put++ = ch;
    }
    *put = 0;
#if !__MSDOS__
    if (!(var = getenv(buffer))) cfg_error("unknown variable \"%s\"",buffer);
#endif /* !__MSDOS__ */
    return next();
}


static void again(int ch)
{
    if (back) die("internal error: again invoked twice");
    back = ch;
}