parse.y

开放源码的Boot

%{
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include "nodes.h"

void yyerror (char *s);

struct node *config_node;

extern void *xmalloc (size_t size);

%}

%union {
	char *string;
	struct node *node;
	unsigned long integer;
	unsigned int flags;
};

%token ARGS
%token FLAGS
%token <integer> INTEGER
%token INITRD
%token KERNEL
%token NAME
%token NORDLOAD
%token NORDPROMPT
%token PASSWORD
%token PATH
%token PONARGS
%token <size> RAMDISK
%token RDLOAD
%token RDPROMPT
%token RDSTART
%token READONLY
%token READWRITE
%token RISCOS
%token ROOT
%token <string> STRING
%token CONFIG

%type <node> kernelpart
%type <node> kernelbits
%type <node> kernel
%type <node> riscos
%type <node> file
%type <node> descriptor
%type <node> riscospart
%type <node> riscosbits
%type <node> configpart
%type <node> configbits
%type <node> cfg
%type <flags> flags
%type <flags> flagbits;

%%

config:		file
		{
			config_node = $1;
		}
	;

file:		descriptor
		{
			$$ = $1;
		}
	|	descriptor file
		{
			$1->next = $2;
			$$ = $1;
		}
	;

descriptor:	kernel
		{
			$$ = $1;
		}
	|	riscos
		{
			$$ = $1;
		}
	|	cfg
		{
			$$ = $1;
		}
	;

kernel:		KERNEL '{' kernelbits
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = KERNEL;
			node->u.n = $3;
			$$ = node;
		}
	;

riscos:		RISCOS '{' riscosbits
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = RISCOS;
			node->u.n = $3;
			$$ = node;
		}
	;

cfg:		CONFIG '{' configbits
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = CONFIG;
			node->u.n = $3;
			$$ = node;
		}
	;

kernelbits:	kernelpart '}' ';'
		{
			$$ = $1;
		}
	|	kernelpart kernelbits
		{
			$1->next = $2;
			$$ = $1;
		}
	;

riscosbits:	riscospart '}' ';'
		{
			$$ = $1;
		}
	|	riscospart riscosbits
		{
			$1->next = $2;
			$$ = $1;
		}
	;

configbits:	configpart '}' ';'
		{
			$$ = $1;
		}
	;

kernelpart:	NAME '=' STRING ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = NAME;
			node->u.string = xmalloc (strlen ($3)+1);
			strcpy (node->u.string, $3);
			$$ = node;
		}
	|	ARGS '=' STRING ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = ARGS;
			node->u.string = xmalloc (strlen ($3)+1);
			strcpy (node->u.string, $3);
			$$ = node;
		}
	|	FLAGS '=' flags
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = FLAGS;
			node->u.flags = $3;
			$$ = node;
		}
	|	INITRD '=' STRING ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = INITRD;
			node->u.string = xmalloc (strlen ($3)+1);
			strcpy (node->u.string, $3);
			$$ = node;
		}
	|	PASSWORD '=' STRING ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = PASSWORD;
			node->u.string = xmalloc (strlen ($3)+1);
			strcpy (node->u.string, $3);
			$$ = node;
		}
	|	PATH '=' STRING ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = PATH;
			node->u.string = xmalloc (strlen ($3)+1);
			strcpy (node->u.string, $3);
			$$ = node;
		}
	|	RAMDISK '=' INTEGER ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = RAMDISK;
			node->u.size = $3;
			$$ = node;
		}
	|	RDSTART '=' INTEGER ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = RDSTART;
			node->u.offset = $3;
			$$ = node;
		}
	|	ROOT '=' STRING ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = ROOT;
			node->u.string = xmalloc (strlen ($3)+1);
			strcpy (node->u.string, $3);
			$$ = node;
		}
	;

riscospart:	NAME '=' STRING ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = NAME;
			node->u.string = xmalloc (strlen ($3)+1);
			strcpy (node->u.string, $3);
			$$ = node;
		}
	|	ARGS '=' STRING ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = ARGS;
			node->u.string = xmalloc (strlen ($3)+1);
			strcpy (node->u.string, $3);
			$$ = node;
		}
	|	PASSWORD '=' STRING ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = PASSWORD;
			node->u.string = xmalloc (strlen ($3)+1);
			strcpy (node->u.string, $3);
			$$ = node;
		}
	;

configpart:	ROOT '=' STRING ';'
		{
			struct node *node;
			node = xmalloc (sizeof (struct node));
			node->type = ROOT;
			node->u.string = xmalloc (strlen ($3)+1);
			strcpy (node->u.string, $3);
			$$ = node;
		}
	;

flags:		flagbits ';'
		{
			$$ = $1;
		}
	|	flagbits flags
		{
			$$ = $1 | $2;
			$$ = $$ & ((~$$) >> 16);
		}

flagbits:	RDLOAD
		{
			$$ = FLAG_RDLOAD;
		}
	|	NORDLOAD
		{
			$$ = FLAG_RDLOAD << 16;
		}
	|	RDPROMPT
		{
			$$ = FLAG_RDPROMPT;
		}
	|	NORDPROMPT
		{
			$$ = FLAG_RDPROMPT << 16;
		}
	|	READONLY
		{
			$$ = FLAG_READONLY;
		}
	|	READWRITE
		{
			$$ = FLAG_READONLY << 16;
		}
	|	PONARGS
		{
			$$ = FLAG_PONARGS;
		}
	;		
%%

void yyerror (char *s)
{
	fprintf (stderr, "%s\n", s);
}