Willy Tarreau | baaee00 | 2006-06-26 02:48:02 +0200 | [diff] [blame^] | 1 | /* |
| 2 | include/proto/backend.h |
| 3 | Functions prototypes for the backend. |
| 4 | |
| 5 | Copyright (C) 2000-2006 Willy Tarreau - w@1wt.eu |
| 6 | |
| 7 | This library is free software; you can redistribute it and/or |
| 8 | modify it under the terms of the GNU Lesser General Public |
| 9 | License as published by the Free Software Foundation, version 2.1 |
| 10 | exclusively. |
| 11 | |
| 12 | This library is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | Lesser General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU Lesser General Public |
| 18 | License along with this library; if not, write to the Free Software |
| 19 | Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #ifndef _PROTO_BACKEND_H |
| 23 | #define _PROTO_BACKEND_H |
| 24 | |
| 25 | |
| 26 | #include <types/backend.h> |
| 27 | #include <types/session.h> |
| 28 | |
| 29 | #include <proto/queue.h> |
| 30 | |
| 31 | int assign_server(struct session *s); |
| 32 | int assign_server_address(struct session *s); |
| 33 | int assign_server_and_queue(struct session *s); |
| 34 | int connect_server(struct session *s); |
| 35 | int srv_count_retry_down(struct session *t, int conn_err); |
| 36 | int srv_retryable_connect(struct session *t); |
| 37 | int srv_redispatch_connect(struct session *t); |
| 38 | |
| 39 | void recount_servers(struct proxy *px); |
| 40 | void recalc_server_map(struct proxy *px); |
| 41 | |
| 42 | |
| 43 | /* |
| 44 | * This function tries to find a running server with free connection slots for |
| 45 | * the proxy <px> following the round-robin method. |
| 46 | * If any server is found, it will be returned and px->srv_rr_idx will be updated |
| 47 | * to point to the next server. If no valid server is found, NULL is returned. |
| 48 | */ |
| 49 | static inline struct server *get_server_rr_with_conns(struct proxy *px) |
| 50 | { |
| 51 | int newidx; |
| 52 | struct server *srv; |
| 53 | |
| 54 | if (px->srv_map_sz == 0) |
| 55 | return NULL; |
| 56 | |
| 57 | if (px->srv_rr_idx < 0 || px->srv_rr_idx >= px->srv_map_sz) |
| 58 | px->srv_rr_idx = 0; |
| 59 | newidx = px->srv_rr_idx; |
| 60 | |
| 61 | do { |
| 62 | srv = px->srv_map[newidx++]; |
| 63 | if (!srv->maxconn || srv->cur_sess < srv_dynamic_maxconn(srv)) { |
| 64 | px->srv_rr_idx = newidx; |
| 65 | return srv; |
| 66 | } |
| 67 | if (newidx == px->srv_map_sz) |
| 68 | newidx = 0; |
| 69 | } while (newidx != px->srv_rr_idx); |
| 70 | |
| 71 | return NULL; |
| 72 | } |
| 73 | |
| 74 | |
| 75 | /* |
| 76 | * This function tries to find a running server for the proxy <px> following |
| 77 | * the round-robin method. |
| 78 | * If any server is found, it will be returned and px->srv_rr_idx will be updated |
| 79 | * to point to the next server. If no valid server is found, NULL is returned. |
| 80 | */ |
| 81 | static inline struct server *get_server_rr(struct proxy *px) |
| 82 | { |
| 83 | if (px->srv_map_sz == 0) |
| 84 | return NULL; |
| 85 | |
| 86 | if (px->srv_rr_idx < 0 || px->srv_rr_idx >= px->srv_map_sz) |
| 87 | px->srv_rr_idx = 0; |
| 88 | return px->srv_map[px->srv_rr_idx++]; |
| 89 | } |
| 90 | |
| 91 | |
| 92 | /* |
| 93 | * This function tries to find a running server for the proxy <px> following |
| 94 | * the source hash method. Depending on the number of active/backup servers, |
| 95 | * it will either look for active servers, or for backup servers. |
| 96 | * If any server is found, it will be returned. If no valid server is found, |
| 97 | * NULL is returned. |
| 98 | */ |
| 99 | static inline struct server *get_server_sh(struct proxy *px, char *addr, int len) |
| 100 | { |
| 101 | unsigned int h, l; |
| 102 | |
| 103 | if (px->srv_map_sz == 0) |
| 104 | return NULL; |
| 105 | |
| 106 | l = h = 0; |
| 107 | if (px->srv_act > 1 || (px->srv_act == 0 && px->srv_bck > 1)) { |
| 108 | while ((l + sizeof (int)) <= len) { |
| 109 | h ^= ntohl(*(unsigned int *)(&addr[l])); |
| 110 | l += sizeof (int); |
| 111 | } |
| 112 | h %= px->srv_map_sz; |
| 113 | } |
| 114 | return px->srv_map[h]; |
| 115 | } |
| 116 | |
| 117 | |
| 118 | #endif /* _PROTO_BACKEND_H */ |
| 119 | |
| 120 | /* |
| 121 | * Local variables: |
| 122 | * c-indent-level: 8 |
| 123 | * c-basic-offset: 8 |
| 124 | * End: |
| 125 | */ |