X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fsystemd%2Fsd-resolv.h;fp=src%2Fsystemd%2Fsd-resolv.h;h=47608ce380bd51a5d7f946ab6857a7629060c34e;hb=5681d7fb8be37771c152d21ea6e95597d664e3f1;hp=0000000000000000000000000000000000000000;hpb=0b54473e9b73d867ed7807507a0fb5adc8137b10;p=elogind.git diff --git a/src/systemd/sd-resolv.h b/src/systemd/sd-resolv.h new file mode 100644 index 000000000..47608ce38 --- /dev/null +++ b/src/systemd/sd-resolv.h @@ -0,0 +1,158 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +#ifndef foosdresolvhfoo +#define foosdresolvhfoo + +/*** + This file is part of systemd. + + Copyright 2005-2008 Lennart Poettering + + systemd 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 2.1 of the License, or + (at your option) any later version. + + systemd 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 systemd; If not, see . +***/ + +#include +#include +#include +#include "_sd-common.h" + +_SD_BEGIN_DECLARATIONS; + +/** \mainpage + * + * \section moo Method of operation + * + * To use libasyncns allocate an asyncns_t object with + * asyncns_new(). This will spawn a number of worker threads (or processes, depending on what is available) which + * are subsequently used to process the queries the controlling + * program issues via asyncns_getaddrinfo() and + * asyncns_getnameinfo(). Use asyncns_free() to shut down the worker + * threads/processes. + * + * Since libasyncns may fork off new processes you have to make sure that + * your program is not irritated by spurious SIGCHLD signals. + */ + +/** An opaque libasyncns session structure */ +typedef struct asyncns asyncns_t; + +/** An opaque libasyncns query structure */ +typedef struct asyncns_query asyncns_query_t; + +/** Allocate a new libasyncns session with n_proc worker processes/threads */ +asyncns_t* asyncns_new(unsigned n_proc); + +/** Free a libasyncns session. This destroys all attached + * asyncns_query_t objects automatically */ +void asyncns_free(asyncns_t *asyncns); + +/** Return the UNIX file descriptor to select() for readability + * on. Use this function to integrate libasyncns with your custom main + * loop. */ +int asyncns_fd(asyncns_t *asyncns); + +/** Process pending responses. After this function is called you can + * get the next completed query object(s) using asyncns_getnext(). If + * block is non-zero wait until at least one response has been + * processed. If block is zero, process all pending responses and + * return. */ +int asyncns_wait(asyncns_t *asyncns, int block); + +/** Issue a name to address query on the specified session. The + * arguments are compatible with the ones of libc's + * getaddrinfo(3). The function returns a new query object. When the + * query is completed you may retrieve the results using + * asyncns_getaddrinfo_done().*/ +asyncns_query_t* asyncns_getaddrinfo(asyncns_t *asyncns, const char *node, const char *service, const struct addrinfo *hints); + +/** Retrieve the results of a preceding asyncns_getaddrinfo() + * call. Returns a addrinfo structure and a return value compatible + * with libc's getaddrinfo(3). The query object q is destroyed by this + * call and may not be used any further. Make sure to free the + * returned addrinfo structure with asyncns_freeaddrinfo() and not + * libc's freeaddrinfo(3)! If the query is not completed yet EAI_AGAIN + * is returned.*/ +int asyncns_getaddrinfo_done(asyncns_t *asyncns, asyncns_query_t* q, struct addrinfo **ret_res); + +/** Issue an address to name query on the specified session. The + * arguments are compatible with the ones of libc's + * getnameinfo(3). The function returns a new query object. When the + * query is completed you may retrieve the results using + * asyncns_getnameinfo_done(). Set gethost (resp. getserv) to non-zero + * if you want to query the hostname (resp. the service name). */ +asyncns_query_t* asyncns_getnameinfo(asyncns_t *asyncns, const struct sockaddr *sa, socklen_t salen, int flags, int gethost, int getserv); + +/** Retrieve the results of a preceding asyncns_getnameinfo() + * call. Returns the hostname and the service name in ret_host and + * ret_serv. The query object q is destroyed by this call and may not + * be used any further. If the query is not completed yet EAI_AGAIN is + * returned. */ +int asyncns_getnameinfo_done(asyncns_t *asyncns, asyncns_query_t* q, char *ret_host, size_t hostlen, char *ret_serv, size_t servlen); + +/** Issue a resolver query on the specified session. The arguments are + * compatible with the ones of libc's res_query(3). The function returns a new + * query object. When the query is completed you may retrieve the results using + * asyncns_res_done(). */ +asyncns_query_t* asyncns_res_query(asyncns_t *asyncns, const char *dname, int class, int type); + +/** Issue an resolver query on the specified session. The arguments are + * compatible with the ones of libc's res_search(3). The function returns a new + * query object. When the query is completed you may retrieve the results using + * asyncns_res_done(). */ +asyncns_query_t* asyncns_res_search(asyncns_t *asyncns, const char *dname, int class, int type); + +/** Retrieve the results of a preceding asyncns_res_query() or + * asyncns_res_search call. The query object q is destroyed by this + * call and may not be used any further. Returns a pointer to the + * answer of the res_query call. If the query is not completed yet + * -EAGAIN is returned, on failure -errno is returned, otherwise the + * length of answer is returned. Make sure to free the answer is a + * call to asyncns_freeanswer(). */ +int asyncns_res_done(asyncns_t *asyncns, asyncns_query_t* q, unsigned char **answer); + +/** Return the next completed query object. If no query has been + * completed yet, return NULL. Please note that you need to run + * asyncns_wait() before this function will return sensible data. */ +asyncns_query_t* asyncns_getnext(asyncns_t *asyncns); + +/** Return the number of query objects (completed or not) attached to + * this session */ +int asyncns_getnqueries(asyncns_t *asyncns); + +/** Cancel a currently running query. q is is destroyed by this call + * and may not be used any futher. */ +void asyncns_cancel(asyncns_t *asyncns, asyncns_query_t* q); + +/** Free the addrinfo structure as returned by + * asyncns_getaddrinfo_done(). Make sure to use this functions instead + * of the libc's freeaddrinfo()! */ +void asyncns_freeaddrinfo(struct addrinfo *ai); + +/** Free the answer data as returned by asyncns_res_done().*/ +void asyncns_freeanswer(unsigned char *answer); + +/** Returns non-zero when the query operation specified by q has been completed */ +int asyncns_isdone(asyncns_t *asyncns, asyncns_query_t*q); + +/** Assign some opaque userdata with a query object */ +void asyncns_setuserdata(asyncns_t *asyncns, asyncns_query_t *q, void *userdata); + +/** Return userdata assigned to a query object. Use + * asyncns_setuserdata() to set this data. If no data has been set + * prior to this call it returns NULL. */ +void* asyncns_getuserdata(asyncns_t *asyncns, asyncns_query_t *q); + +_SD_END_DECLARATIONS; + +#endif