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Diffstat (limited to 'man/man3/9pfid.3')
| -rw-r--r-- | man/man3/9pfid.3 | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/man/man3/9pfid.3 b/man/man3/9pfid.3 new file mode 100644 index 00000000..ac0f2bfc --- /dev/null +++ b/man/man3/9pfid.3 @@ -0,0 +1,204 @@ +.TH 9PFID 3 +.SH NAME +Fid, Fidpool, allocfidpool, freefidpool, allocfid, closefid, lookupfid, removefid, +Req, Reqpool, allocreqpool, freereqpool, allocreq, closereq, lookupreq, removereq \- 9P fid, request tracking +.SH SYNOPSIS +.ft L +.nf +#include <u.h> +#include <libc.h> +#include <fcall.h> +#include <thread.h> +#include <9p.h> +.fi +.PP +.ft L +.nf +.ta \w'\fL 'u +\w'\fLulong 'u +typedef struct Fid +{ + ulong fid; + char omode; /* -1 if not open */ + char *uid; + Qid qid; + File *file; + void *aux; + \fI...\fP +} Fid; +.fi +.PP +.ft L +.nf +.ta \w'\fL 'u +\w'\fLulong 'u +typedef struct Req +{ + ulong tag; + Fcall ifcall; + Fcall ofcall; + Req *oldreq; + void *aux; + \fI...\fP +} Req; +.fi +.PP +.ft L +.nf +.ta \w'\fLFidpool* 'u +Fidpool* allocfidpool(void (*destroy)(Fid*)) +void freefidpool(Fidpool *p) +Fid* allocfid(Fidpool *p, ulong fid) +Fid* lookupfid(Fidpool *p, ulong fid) +void closefid(Fid *f) +void removefid(Fid *f) +.fi +.PP +.ft L +.nf +.ta \w'\fLReqpool* 'u +Reqpool* allocreqpool(void (*destroy)(Req*)) +void freereqpool(Reqpool *p) +Req* allocreq(Reqpool *p, ulong tag) +Req* lookupreq(Reqpool *p, ulong tag) +void closereq(Req *f) +void removereq(Req *r) +.fi +.SH DESCRIPTION +These routines provide management of +.B Fid +and +.B Req +structures from +.BR Fidpool s +and +.BR Reqpool s. +They are primarily used by the 9P server loop +described in +.IR 9p (2). +.PP +.B Fid +structures are intended to represent +active fids in a 9P connection, as +.B Chan +structures do in the Plan 9 kernel. +The +.B fid +element is the integer fid used in the 9P +connection. +.B Omode +is the mode under which the fid was opened, or +.B -1 +if this fid has not been opened yet. +Note that in addition to the values +.BR OREAD , +.BR OWRITE , +and +.BR ORDWR , +.B omode +can contain the various flags permissible in +an open call. +To ignore the flags, use +.BR omode&OMASK . +.B Omode +should not be changed by the client. +The fid derives from a successful authentication by +.BR uid . +.B Qid +contains the qid returned in the last successful +.B walk +or +.B create +transaction involving the fid. +In a file tree-based server, the +.BR Fid 's +.B file +element points at a +.B File +structure +(see +.IR 9pfile (2)) +corresponding to the fid. +The +.B aux +member is intended for use by the +client to hold information specific to a particular +.BR Fid . +With the exception of +.BR aux , +these elements should be treated +as read-only by the client. +.PP +.I Allocfidpool +creates a new +.BR Fidpool . +.I Freefidpool +destroys such a pool. +.I Allocfid +returns a new +.B Fid +whose fid number is +.IR fid . +There must not already be an extant +.B Fid +with that number in the pool. +Once a +.B Fid +has been allocated, it can be looked up by +fid number using +.IR lookupfid . +.BR Fid s +are reference counted: both +.I allocfid +and +.I lookupfid +increment the reference count on the +.B Fid +structure before +returning. +When a reference to a +.B Fid +is no longer needed, +.I closefid +should be called to note the destruction of the reference. +When the last reference to a +.B Fid +is removed, if +.I destroy +(supplied when creating the fid pool) +is not zero, it is called with the +.B Fid +as a parameter. +It should perform whatever cleanup is necessary +regarding the +.B aux +element. +.I Removefid +is equivalent to +.I closefid +but also removes the +.B Fid +from the pool. +Note that due to lingering references, +the return of +.I removefid +may not mean that +.I destroy +has been called. +.PP +.IR Allocreqpool , +.IR freereqpool , +.IR allocreq , +.IR lookupreq , +.IR closereq , +and +.I removereq +are analogous but +operate on +.BR Reqpool s +and +.B Req +structures. +.SH SOURCE +.B /sys/src/lib9p +.SH SEE ALSO +.IR 9p (2), +.IR 9pfile (2) |