CTDB Project ibwrapper
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File ibwrapper.h:
/* * Infiniband Verbs API socket-like wrapper * Copyright (C) Peter Somogyi 2006 * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* Server communication state */ typedef enum { IBWS_INIT = 0, /* ctx start - after ibw_init */ IBWS_READY, /* after ibw_bind & ibw_listen */ IBWS_CONNECT_REQUEST, /* after [IBWS_READY + incoming request] */ /* => [(ibw_accept)IBWS_READY | (ibw_disconnect)STOPPED | ERROR] */ IBWS_STOPPED, /* normal stop <= ibw_disconnect+(IBWS_READY | IBWS_CONNECT_REQUEST) */ IBWS_ERROR /* abnormal state; ibw_stop must be called after this */ } ibw_state_ctx; /* Connection state */ typedef struct _ibw_ctx { void *ctx_userdata; /* see ibw_init */ ibw_state_ctx state; void *internal; } ibw_ctx; typedef enum { IBWC_INIT = 0, /* conn start - internal state */ IBWC_CONNECTED, /* after ibw_accept or ibw_connect */ IBWC_DISCONNECTED, /* after ibw_disconnect */ IBWC_ERROR } ibw_state_conn; typedef struct _ibw_conn { ibw_ctx *ctx; ibw_state_conn state; void *conn_userdata; /* see ibw_connect and ibw_accept */ void *internal; } ibw_conn; /* * (name, value) pair for array param of ibw_init */ typedef struct _ibw_initattr { const char *name; const char *value; } ibw_initattr; /* * Callback function definition which should inform you about * connection state change * This callback is invoked from within ibw_process_event. * Both <conn> and <ctx> can be NULL if their state didn't change. * Return nonzero on error. */ typedef int (*ibw_connstate_fn_t)(ibw_ctx *ctx, ibw_conn *conn); /* * Callback function definition which should process incoming packets * This callback is invoked from within ibw_process_event. * Return nonzero on error. * * Important: you mustn't store buf pointer for later use. Process its contents before returning. */ typedef int (*ibw_receive_fn_t)(ibw_conn *conn, void *buf, int n); /* * Callback function to request ibw_process_event to be called with fd_index * when this fd is set. * This is necessary because upper layer shouldn't be aware of when to use that fd. * fd_index is a unique value (normally index of the internal fd array) * * It's up to the actual implementation of this interface when this callback is called * (e.g. in ibw_init, ibw_bind, ibw_listen ...) */ typedef int (*ibw_add_event_fn_t)(int fd, int fd_index, void *ctx_userdata); /* * Callback function to request this fd shouldn't be used any more. * * fd_index is a unique value (normally index of the internal fd array) - upper * layer possibly needn't use this. * * It's up to the actual implementation of this interface when this callback is called * (e.g. in ibw_destroy, talloc_free, ...) */ typedef int (*ibw_rm_event_fn_t)(int fd, int fd_index, void *ctx_userdata); /* * settings: array of (name, value) pairs * where name is one of: * dev_name [default is the first one] * rx_depth [default is 500] * mtu [default is 1024] * ib_port [default is 1] * * Must be called _ONCE_ for each node. * * returns non-NULL on success * * talloc_free must be called for the result in IBWS_STOPPED; * it will close resources by destructor * connections(ibw_conn *) must have been closed prior talloc_free */ ibw_ctx *ibw_init(ibw_initattr *attr, int nattr, void *ctx_userdata, ibw_connstate_fn_t ibw_connstate, ibw_receive_fn_t ibw_receive, ibw_add_event_fn_t ibw_add_event, ibw_rm_event_fn_t ibw_rm_event); /* * Must be called in states of (IBWS_ERROR, IBWS_READY, IBWS_CONNECT_REQUEST) * * It will send out disconnect requests and free up ibw_conn structures. * The ctx->state will transit to IBWS_STOPPED after every conn are disconnected. * During that time, you mustn't send/recv/disconnect any more. * Only after ctx->state=IBWS_STOPPED you can talloc_free the ctx. */ int ibw_stop(ibw_ctx *ctx); /*************** connection initiation - like stream sockets *****/ /* * works like socket bind * needs a normal internet address here * * return 0 on success */ int ibw_bind(ibw_ctx *ctx, struct sockaddr_in *my_addr); /* * works like socket listen * non-blocking * enables accepting incoming connections (after IBWS_READY) * (it doesn't touch ctx->state by itself) * * returns 0 on success */ int ibw_listen(ibw_ctx *ctx, int backlog); /* * works like socket accept * initializes a connection to a client * must be called when state=IBWS_CONNECT_REQUEST * * returns 0 on success * * You have +1 waiting here: you will get ibw_conn (having the * same <conn_userdata> member) structure in ibw_connstate_fn_t. * * Important: you won't get remote IP address (only internal conn info) */ int ibw_accept(ibw_ctx *ctx, void *conn_userdata); /* * Needs a normal internet address here * can be called within IBWS_READY|IBWS_CONNECT_REQUEST * * returns non-NULL on success * * You have +1 waiting here: you will get ibw_conn (having the * same <conn_userdata> member) structure in ibw_connstate_fn_t. */ int ibw_connect(ibw_ctx *ctx, struct sockaddr_in *serv_addr, void *conn_userdata); /* * Sends out a disconnect request. * You should process fds after calling this function * and then process it with ibw_process_event normally * until you get conn->state = IBWC_DISCONNECTED * * You mustn't talloc_free <conn> yet right after this, * first wait for IBWC_DISCONNECTED. */ void ibw_disconnect(ibw_conn *conn); /************ Infiniband specific event loop wrapping ******************/ /* * Must be called in all cases after selecting/polling * for FDs set via ibw_add_event_fn_t. * * fd_index: fd identifier passed in ibw_add_event_fn_t * with the same fd was set there. */ int ibw_process_event(ibw_ctx *ctx, int fd_index); /* * You have to use this buf to fill in before send. * It's just to avoid memcpy.in ibw_send. * Use the same (buf, key) pair with ibw_send. * * Returns 0 on success. */ int ibw_alloc_send_buf(ibw_conn *conn, void **buf, void **key, int n); /* * Send the message in one * Can be invoked any times (should fit into buffers) and at any time * (in conn->state=IBWC_CONNECTED) * * You mustn't use (buf, key) any more for sending. */ int ibw_send(ibw_conn *conn, void *buf, void *key, int n); /* * Retrieves the last error * result: always non-zero, mustn't be freed (static) */ const char *ibw_getLastError();