dat.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

#include	"all.h"

Uid*	uid;
char*	uidspace;
short*	gidspace;
RWLock	mainlock;
long	boottime;
Tlock	*tlocks;
Conf	conf;
Cons	cons;
Chan	*chan;
char	service[2*NAMELEN];
char	*progname;
char	*procname;
int	RBUFSIZE;
int	BUFSIZE;
int	DIRPERBUF;
int	INDPERBUF;
int	INDPERBUF2;
int	FEPERBUF;

Filsys	filesys[MAXFILSYS] =
{
	{"main",	{Devwren, 0, 0, 0},	0},
};

Device 	devnone = {Devnone, 0, 0, 0};

Devcall devcall[MAXDEV] = {
	[Devnone]	{0},
	[Devwren]	{wreninit, wrenream, wrencheck, wrensuper, wrenroot, wrensize, wrenread, wrenwrite},
};

char*	tagnames[] =
{
	[Tbuck]		"Tbuck",
	[Tdir]		"Tdir",
	[Tfile]		"Tfile",
	[Tfree]		"Tfree",
	[Tind1]		"Tind1",
	[Tind2]		"Tind2",
	[Tnone]		"Tnone",
	[Tsuper]	"Tsuper",
	[Tvirgo]	"Tvirgo",
	[Tcache]	"Tcache",
};

char	*errstring[MAXERR] =
{
	[Ebadspc]	"attach -- bad specifier",
	[Efid]		"unknown fid",
	[Echar]		"bad character in directory name",
	[Eopen]		"read/write -- on non open fid",
	[Ecount]	"read/write -- count too big",
	[Ealloc]	"phase error -- directory entry not allocated",
	[Eqid]		"phase error -- qid does not match",
	[Eauth]		"authentication failed",
	[Eauthmsg]	"kfs: authentication not required",
	[Eaccess]	"access permission denied",
	[Eentry]	"directory entry not found",
	[Emode]		"open/create -- unknown mode",
	[Edir1]		"walk -- in a non-directory",
	[Edir2]		"create -- in a non-directory",
	[Ephase]	"phase error -- cannot happen",
	[Eexist]	"create -- file exists",
	[Edot]		"create -- . and .. illegal names",
	[Eempty]	"remove -- directory not empty",
	[Ebadu]		"attach -- privileged user",
	[Enotu]		"wstat -- not owner",
	[Enotg]		"wstat -- not in group",
	[Enotl]		"wstat -- attempt to change length",
	[Enotd]		"wstat -- attempt to change directory",
	[Enotm]		"wstat -- unknown type/mode",
	[Ename]		"create/wstat -- bad character in file name",
	[Ewalk]		"walk -- too many (system wide)",
	[Eronly]	"file system read only",
	[Efull]		"file system full",
	[Eoffset]	"read/write -- offset negative",
	[Elocked]	"open/create -- file is locked",
	[Ebroken]	"close/read/write -- lock is broken",
	[Efidinuse]	"fid already in use",
	[Etoolong]	"name too long",
	[Ersc]	"it's russ's fault.  bug him.",
	[Econvert]	"protocol botch",
	[Eqidmode]	"wstat -- qid.type/dir.mode mismatch",
	[Esystem]	"kfs system error",
};