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Diffstat (limited to 'src/providers/fail_over.h')
| -rw-r--r-- | src/providers/fail_over.h | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/src/providers/fail_over.h b/src/providers/fail_over.h new file mode 100644 index 00000000..e581fbaf --- /dev/null +++ b/src/providers/fail_over.h @@ -0,0 +1,108 @@ +#ifndef __FAIL_OVER_H__ +#define __FAIL_OVER_H__ + +#include <stdbool.h> +#include <talloc.h> + +/* Some forward declarations that don't have to do anything with fail over. */ +struct hostent; +struct resolv_ctx; +struct tevent_context; +struct tevent_req; + +enum port_status { + PORT_NEUTRAL, /* We didn't try this port yet. */ + PORT_WORKING, /* This port was reported to work. */ + PORT_NOT_WORKING /* This port was reported to not work. */ +}; + +enum server_status { + SERVER_NAME_NOT_RESOLVED, /* We didn't yet resolved the host name. */ + SERVER_RESOLVING_NAME, /* Name resolving is in progress. */ + SERVER_NAME_RESOLVED, /* We resolved the host name but didn't try to connect. */ + SERVER_WORKING, /* We successfully connected to the server. */ + SERVER_NOT_WORKING /* We tried and failed to connect to the server. */ +}; + +struct fo_ctx; +struct fo_service; +struct fo_server; + +/* + * Create a new fail over context. The 'retry_timeout' argument specifies the + * duration in seconds of how long a server or port will be considered + * non-working after being marked as such. + */ +struct fo_ctx *fo_context_init(TALLOC_CTX *mem_ctx, + time_t retry_timeout); + +/* + * Create a new service structure for 'ctx', saving it to the location pointed + * to by '_service'. The needed memory will be allocated from 'ctx'. + * Service name will be set to 'name'. + */ +int fo_new_service(struct fo_ctx *ctx, + const char *name, + struct fo_service **_service); + +/* + * Look up service named 'name' from the 'ctx' service list. Target of + * '_service' will be set to the service if it was found. + */ +int fo_get_service(struct fo_ctx *ctx, + const char *name, + struct fo_service **_service); + +/* + * Adds a server 'name' to the 'service'. Port 'port' will be used for + * connection. If 'name' is NULL, no server resolution will be done. + */ +int fo_add_server(struct fo_service *service, + const char *name, + int port, + void *user_data); + +/* + * Request the first server from the service's list of servers. It is only + * considered if it is not marked as not working (or the retry interval already + * passed). If the server address wasn't resolved yet, it will be done. + */ +struct tevent_req *fo_resolve_service_send(TALLOC_CTX *mem_ctx, + struct tevent_context *ev, + struct resolv_ctx *resolv, + struct fo_service *service); + +int fo_resolve_service_recv(struct tevent_req *req, + struct fo_server **server); + +/* + * Set feedback about 'server'. Caller should use this to indicate a problem + * with the server itself, not only with the service on that server. This + * should be used, for example, when the IP address of the server can't be + * reached. This setting can affect other services as well, since they can + * share the same server. + */ +void fo_set_server_status(struct fo_server *server, + enum server_status status); + +/* + * Set feedback about the port status. This function should be used when + * the server itself is working but the service is not. When status is set + * to PORT_WORKING, 'server' is also marked as an "active server" for its + * service. When the next fo_resolve_service_send() function is called, this + * server will be preferred. This will hold as long as it is not marked as + * not-working. + */ +void fo_set_port_status(struct fo_server *server, + enum port_status status); + + +void *fo_get_server_user_data(struct fo_server *server); + +int fo_get_server_port(struct fo_server *server); + +const char *fo_get_server_name(struct fo_server *server); + +struct hostent *fo_get_server_hostent(struct fo_server *server); + +#endif /* !__FAIL_OVER_H__ */ |