example/backends.h

   1 /*
   2  * 2008+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
   3  * All rights reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #ifndef __DNET_BACKENDS_H
  17 #define __DNET_BACKENDS_H
  18
  19 #ifdef __cplusplus
  20 extern "C" {
  21 #endif
  22
  23 #include <strings.h>
  24
  25 #include "elliptics/core.h"
  26 #include "elliptics/packet.h"
  27
  28 static inline int64_t dnet_backend_check_get_size(struct dnet_io_attr *io, uint64_t record_size)
  29 {
  30         uint64_t size = io->size;
  31
  32         if (record_size <= io->offset)
  33                 return 0;
  34
  35         if (!record_size && size)
  36                 return -E2BIG;
  37
  38         if (!size || size + io->offset >= record_size) {
  39                 if (!size)
  40                         size = record_size;
  41
  42                 if (size + io->offset >= record_size) {
  43                         if (io->offset >= record_size)
  44                                 size = 0;
  45                         else
  46                                 size = record_size - io->offset;
  47                 }
  48         }
  49
  50         return size;
  51 }
  52
  53 int backend_stat(void *state, char *path, struct dnet_cmd *cmd);
  54
  55 int backend_stat_low_level(const char *path, struct dnet_stat *st);
  56
  57 static inline char *file_backend_get_dir(const unsigned char *id, uint64_t bit_num, char *dst)
  58 {
  59         char *res = dnet_dump_id_len_raw(id, ALIGN(bit_num, 8) / 8, dst);
  60
  61         if (res)
  62                 res[bit_num / 4] = '\0';
  63         return res;
  64 }
  65
  66 struct dnet_config_backend;
  67 struct dnet_config_entry {
  68         char            key[64];
  69         int             (*callback)(struct dnet_config_backend *b, char *key, char *value);
  70 };
  71
  72 struct dnet_config_backend {
  73         char                            name[64];
  74         struct dnet_config_entry        *ent;
  75         int                             num;
  76         int                             size;
  77         void                            *data;
  78
  79         unsigned long long              storage_size;
  80         unsigned long long              storage_free;
  81
  82         struct dnet_log                 *log;
  83
  84         int                             (* init)(struct dnet_config_backend *b, struct dnet_config *cfg);
  85         void                            (* cleanup)(struct dnet_config_backend *b);
  86
  87         struct dnet_backend_callbacks   cb;
  88 };
  89
  90 int dnet_backend_register(struct dnet_config_backend *b);
  91
  92 int dnet_file_backend_init(void);
  93 void dnet_file_backend_exit(void);
  94
  95 int dnet_eblob_backend_init(void);
  96 void dnet_eblob_backend_exit(void);
  97
  98 int backend_storage_size(struct dnet_config_backend *b, const char *root);
  99
 100 int dnet_backend_check_log_mask(uint32_t mask);
 101 void dnet_backend_log_raw(uint32_t mask, const char *fmt, ...) __attribute__ ((format(printf, 2, 3)));
 102 #define dnet_backend_log(mask, format, a...)                            \
 103         do {                                                            \
 104                 if (dnet_backend_check_log_mask(mask))                  \
 105                         dnet_backend_log_raw(mask, format, ##a);        \
 106         } while (0)
 107
 108 #ifdef __cplusplus
 109 }
 110 #endif
 111
 112 #endif /* __DNET_BACKENDS_H */