| rsc | be7cbb4 | 2005-07-12 15:24:18 +0000 | [diff] [blame] | 1 | .TH VENTI-SERVER 3 |
| 2 | .SH NAME |
| 3 | vtsrvhello, vtlisten, vtgetreq, vtrespond \- Venti server |
| 4 | .SH SYNOPSIS |
| 5 | .PP |
| 6 | .ft L |
| 7 | #include <u.h> |
| 8 | .br |
| 9 | #include <libc.h> |
| 10 | .br |
| 11 | #include <venti.h> |
| 12 | .ta +\w'\fLVtReq* 'u |
| 13 | .PP |
| 14 | .ft L |
| 15 | .nf |
| 16 | typedef struct VtReq |
| 17 | { |
| 18 | VtFcall tx; |
| 19 | VtFcall rx; |
| 20 | ... |
| 21 | } VtReq; |
| 22 | .PP |
| 23 | .B |
| 24 | int vtsrvhello(VtConn *z) |
| 25 | .PP |
| 26 | .B |
| 27 | VtSrv* vtlisten(char *addr) |
| 28 | .PP |
| 29 | .B |
| 30 | VtReq* vtgetreq(VtSrv *srv) |
| 31 | .PP |
| 32 | .B |
| 33 | void vtrespond(VtReq *req) |
| 34 | .SH DESCRIPTION |
| 35 | These routines execute the server side of the |
| 36 | .IR venti (7) |
| 37 | protocol. |
| 38 | .PP |
| 39 | .I Vtsrvhello |
| 40 | executes the server side of the initial |
| 41 | .B hello |
| 42 | transaction. |
| 43 | It sets |
| 44 | .IB z -> uid |
| 45 | with the user name claimed by the other side. |
| 46 | Each new connection must be initialized by running |
| 47 | .I vtversion |
| 48 | and then |
| 49 | .IR vtsrvhello . |
| 50 | The framework below takes care of this detail automatically; |
| 51 | .I vtsrvhello |
| 52 | is provided for programs that do not use the functions below. |
| 53 | .PP |
| 54 | .IR Vtlisten , |
| 55 | .IR vtgetreq , |
| 56 | and |
| 57 | .I vtrespond |
| 58 | provide a simple framework for writing Venti servers. |
| 59 | .PP |
| 60 | .I Vtlisten |
| 61 | announces at the network address |
| 62 | .IR addr , |
| 63 | returning a fresh |
| 64 | .B VtSrv |
| 65 | structure representing the service. |
| 66 | .PP |
| 67 | .I Vtgetreq |
| 68 | waits for and returns |
| 69 | the next |
| 70 | .BR read , |
| 71 | .BR write , |
| 72 | .BR sync , |
| 73 | or |
| 74 | .B ping |
| 75 | request from any client connected to |
| 76 | the service |
| 77 | .IR srv . |
| 78 | .B Hello |
| 79 | and |
| 80 | .B goodbye |
| 81 | messages are handled internally and not returned to the client. |
| 82 | The interface does not distinguish between the |
| 83 | different clients that may be connected at any given time. |
| 84 | The request can be found in the |
| 85 | .I tx |
| 86 | field of the returned |
| 87 | .BR VtReq . |
| 88 | .PP |
| 89 | Once a request has been served and a response stored in |
| 90 | .IB r ->rx \fR, |
| 91 | the server should call |
| 92 | .IR vtrespond |
| 93 | to send the response to the client. |
| 94 | .I Vtrespond |
| 95 | frees the structure |
| 96 | .I r |
| 97 | as well as the packets |
| 98 | .IB r ->tx.data |
| 99 | and |
| 100 | .IB r ->rx.data \fR. |
| 101 | .SH EXAMPLE |
| 102 | .B \*9/src/venti/cmd |
| 103 | contains two simple Venti servers |
| 104 | .B ro.c |
| 105 | and |
| 106 | .B devnull.c |
| 107 | written using these routines. |
| 108 | .I Ro |
| 109 | is a read-only Venti proxy (it rejects |
| 110 | .B write |
| 111 | requests). |
| 112 | .I Devnull |
| 113 | is a write-only Venti server: it discards all |
| 114 | blocks written to it and returns error on all reads. |
| 115 | .SH SOURCE |
| 116 | .B \*9/src/libventi |
| 117 | .SH SEE ALSO |
| 118 | .IR venti (1), |
| 119 | .IR venti (3), |
| 120 | .IR venti-conn (3), |
| 121 | .IR venti-packet (3) |
