GNUnet  0.20.0
plugin_datacache_postgres.c File Reference

postgres for an implementation of a database backend for the datacache More...

#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_pq_lib.h"
#include "gnunet_datacache_plugin.h"
Include dependency graph for plugin_datacache_postgres.c:

Go to the source code of this file.

Data Structures

struct  Plugin
 Handle for a plugin. More...
 
struct  HandleResultContext
 Closure for handle_results. More...
 
struct  ExtractResultContext
 Closure for extract_result_cb. More...
 

Macros

#define LOG(kind, ...)   GNUNET_log_from (kind, "datacache-postgres", __VA_ARGS__)
 
#define OVERHEAD   (sizeof(struct GNUNET_HashCode) + 24)
 Per-entry overhead estimate. More...
 

Functions

static enum GNUNET_GenericReturnValue init_connection (struct Plugin *plugin)
 Get a database handle. More...
 
static ssize_t postgres_plugin_put (void *cls, uint32_t prox, const struct GNUNET_DATACACHE_Block *block)
 Store an item in the datastore. More...
 
static void handle_results (void *cls, PGresult *result, unsigned int num_results)
 Function to be called with the results of a SELECT statement that has returned num_results results. More...
 
static unsigned int postgres_plugin_get (void *cls, const struct GNUNET_HashCode *key, enum GNUNET_BLOCK_Type type, GNUNET_DATACACHE_Iterator iter, void *iter_cls)
 Iterate over the results for a particular key in the datastore. More...
 
static enum GNUNET_GenericReturnValue postgres_plugin_del (void *cls)
 Delete the entry with the lowest expiration value from the datacache right now. More...
 
static void extract_result_cb (void *cls, PGresult *result, unsigned int num_results)
 Function to be called with the results of a SELECT statement that has returned num_results results. More...
 
static unsigned int postgres_plugin_get_closest (void *cls, const struct GNUNET_HashCode *key, enum GNUNET_BLOCK_Type type, unsigned int num_results, GNUNET_DATACACHE_Iterator iter, void *iter_cls)
 Iterate over the results that are "close" to a particular key in the datacache. More...
 
void * libgnunet_plugin_datacache_postgres_init (void *cls)
 Entry point for the plugin. More...
 
void * libgnunet_plugin_datacache_postgres_done (void *cls)
 Exit point from the plugin. More...
 

Detailed Description

postgres for an implementation of a database backend for the datacache

Author
Christian Grothoff

Definition in file plugin_datacache_postgres.c.

Macro Definition Documentation

◆ LOG

#define LOG (   kind,
  ... 
)    GNUNET_log_from (kind, "datacache-postgres", __VA_ARGS__)

Definition at line 31 of file plugin_datacache_postgres.c.

◆ OVERHEAD

#define OVERHEAD   (sizeof(struct GNUNET_HashCode) + 24)

Per-entry overhead estimate.

Definition at line 36 of file plugin_datacache_postgres.c.

Function Documentation

◆ init_connection()

static enum GNUNET_GenericReturnValue init_connection ( struct Plugin plugin)
static

Get a database handle.

Parameters
pluginglobal context
Returns
GNUNET_OK on success, GNUNET_SYSERR on error

Definition at line 1 of file plugin_datacache_postgres.c.

68 {
69  struct GNUNET_PQ_PreparedStatement ps[] = {
70  GNUNET_PQ_make_prepare ("getkt",
71  "SELECT expiration_time,type,ro,value,trunc,path"
72  " FROM datacache.gn180dc"
73  " WHERE key=$1 AND type=$2 AND expiration_time >= $3"),
74  GNUNET_PQ_make_prepare ("getk",
75  "SELECT expiration_time,type,ro,value,trunc,path"
76  " FROM datacache.gn180dc"
77  " WHERE key=$1 AND expiration_time >= $2"),
78  GNUNET_PQ_make_prepare ("getex",
79  "SELECT LENGTH(value) AS len,oid,key"
80  " FROM datacache.gn180dc"
81  " WHERE expiration_time < $1"
82  " ORDER BY expiration_time ASC LIMIT 1"),
83  GNUNET_PQ_make_prepare ("getm",
84  "SELECT LENGTH(value) AS len,oid,key"
85  " FROM datacache.gn180dc"
86  " ORDER BY prox ASC, expiration_time ASC LIMIT 1"),
87  GNUNET_PQ_make_prepare ("get_closest",
88  "(SELECT expiration_time,type,ro,value,trunc,path,key"
89  " FROM datacache.gn180dc"
90  " WHERE key >= $1"
91  " AND expiration_time >= $2"
92  " AND ( (type = $3) OR ( 0 = $3) )"
93  " ORDER BY key ASC"
94  " LIMIT $4)"
95  " UNION "
96  "(SELECT expiration_time,type,ro,value,trunc,path,key"
97  " FROM datacache.gn180dc"
98  " WHERE key <= $1"
99  " AND expiration_time >= $2"
100  " AND ( (type = $3) OR ( 0 = $3) )"
101  " ORDER BY key DESC"
102  " LIMIT $4)"),
103  GNUNET_PQ_make_prepare ("delrow",
104  "DELETE FROM datacache.gn180dc"
105  " WHERE oid=$1"),
106  GNUNET_PQ_make_prepare ("put",
107  "INSERT INTO datacache.gn180dc"
108  " (type, ro, prox, expiration_time, key, value, trunc, path) "
109  "VALUES ($1, $2, $3, $4, $5, $6, $7, $8)"),
111  };
112 
113  plugin->dbh = GNUNET_PQ_connect_with_cfg (plugin->env->cfg,
114  "datacache-postgres",
115  "datacache-",
116  NULL,
117  ps);
118  if (NULL == plugin->dbh)
119  return GNUNET_SYSERR;
120  return GNUNET_OK;
121 }
struct TestcasePlugin * plugin
The process handle to the testbed service.
struct GNUNET_PQ_Context * GNUNET_PQ_connect_with_cfg(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *load_path_suffix, const struct GNUNET_PQ_ExecuteStatement *es, const struct GNUNET_PQ_PreparedStatement *ps)
Connect to a postgres database using the configuration option "CONFIG" in section.
Definition: pq_connect.c:619
struct GNUNET_PQ_PreparedStatement GNUNET_PQ_make_prepare(const char *name, const char *sql)
Create a struct GNUNET_PQ_PreparedStatement.
Definition: pq_prepare.c:30
#define GNUNET_PQ_PREPARED_STATEMENT_END
Terminator for prepared statement list.
@ GNUNET_OK
@ GNUNET_SYSERR
Information needed to prepare a list of SQL statements using GNUNET_PQ_prepare_statements().

Referenced by libgnunet_plugin_datacache_postgres_init().

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◆ postgres_plugin_put()

static ssize_t postgres_plugin_put ( void *  cls,
uint32_t  prox,
const struct GNUNET_DATACACHE_Block block 
)
static

Store an item in the datastore.

Parameters
clsclosure (our struct Plugin)
proxproximity of key to my PID
blockdata to store
Returns
0 if duplicate, -1 on error, number of bytes used otherwise

Definition at line 133 of file plugin_datacache_postgres.c.

136 {
137  struct Plugin *plugin = cls;
138  uint32_t type32 = (uint32_t) block->type;
139  uint32_t ro32 = (uint32_t) block->type;
140  struct GNUNET_PQ_QueryParam params[] = {
147  block->data_size),
149  (0 == block->put_path_length)
152  block->put_path,
153  block->put_path_length
154  * sizeof(struct GNUNET_DHT_PathElement)),
156  };
158 
160  "put",
161  params);
162  if (0 > ret)
163  return -1;
164  plugin->num_items++;
165  return block->data_size + OVERHEAD;
166 }
static int ret
Return value of the commandline.
Definition: gnunet-abd.c:81
GNUNET_DB_QueryStatus
Status code returned from functions running database commands.
Definition: gnunet_db_lib.h:37
struct GNUNET_PQ_QueryParam GNUNET_PQ_query_param_fixed_size(const void *ptr, size_t ptr_size)
Generate query parameter for a buffer ptr of ptr_size bytes.
#define GNUNET_PQ_query_param_auto_from_type(x)
Generate fixed-size query parameter with size determined by variable type.
struct GNUNET_PQ_QueryParam GNUNET_PQ_query_param_null(void)
Generate query parameter to create a NULL value.
struct GNUNET_PQ_QueryParam GNUNET_PQ_query_param_absolute_time(const struct GNUNET_TIME_Absolute *x)
Generate query parameter for an absolute time value.
#define GNUNET_PQ_query_param_end
End of query parameter specification.
struct GNUNET_PQ_QueryParam GNUNET_PQ_query_param_uint32(const uint32_t *x)
Generate query parameter for an uint32_t in host byte order.
enum GNUNET_DB_QueryStatus GNUNET_PQ_eval_prepared_non_select(struct GNUNET_PQ_Context *db, const char *statement_name, const struct GNUNET_PQ_QueryParam *params)
Execute a named prepared statement that is NOT a SELECT statement in connection using the given param...
Definition: pq_eval.c:135
#define OVERHEAD
Per-entry overhead estimate.
const struct GNUNET_DHT_PathElement * put_path
PUT path taken by the block, array of peer identities.
enum GNUNET_BLOCK_Type type
Type of the block.
const void * data
Actual block data.
struct GNUNET_PeerIdentity trunc_peer
If the path was truncated, this is the peer ID at which the path was truncated.
struct GNUNET_HashCode key
Key of the block.
size_t data_size
Number of bytes in data.
unsigned int put_path_length
Length of the put_path array.
struct GNUNET_TIME_Absolute expiration_time
When does the block expire?
A (signed) path tracking a block's flow through the DHT is represented by an array of path elements,...
Description of a DB query parameter.
Definition: gnunet_pq_lib.h:83
Handle for a plugin.
Definition: block.c:38

References GNUNET_DATACACHE_Block::data, GNUNET_DATACACHE_Block::data_size, GNUNET_DATACACHE_Block::expiration_time, GNUNET_PQ_eval_prepared_non_select(), GNUNET_PQ_query_param_absolute_time(), GNUNET_PQ_query_param_auto_from_type, GNUNET_PQ_query_param_end, GNUNET_PQ_query_param_fixed_size(), GNUNET_PQ_query_param_null(), GNUNET_PQ_query_param_uint32(), GNUNET_DATACACHE_Block::key, OVERHEAD, plugin, GNUNET_DATACACHE_Block::put_path, GNUNET_DATACACHE_Block::put_path_length, ret, GNUNET_DATACACHE_Block::trunc_peer, and GNUNET_DATACACHE_Block::type.

Referenced by libgnunet_plugin_datacache_postgres_init().

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◆ handle_results()

static void handle_results ( void *  cls,
PGresult *  result,
unsigned int  num_results 
)
static

Function to be called with the results of a SELECT statement that has returned num_results results.

Parse the result and call the callback given in cls

Parameters
clsclosure of type struct HandleResultContext
resultthe postgres result
num_resultsthe number of results in result

Definition at line 201 of file plugin_datacache_postgres.c.

204 {
205  struct HandleResultContext *hrc = cls;
206 
207  for (unsigned int i = 0; i < num_results; i++)
208  {
209  uint32_t type32;
210  uint32_t bro32;
211  void *data;
212  struct GNUNET_DATACACHE_Block block;
213  void *path = NULL;
214  size_t path_size = 0;
215  struct GNUNET_PQ_ResultSpec rs[] = {
216  GNUNET_PQ_result_spec_absolute_time ("expiration_time",
217  &block.expiration_time),
219  &type32),
221  &bro32),
223  &data,
224  &block.data_size),
226  &block.trunc_peer),
229  &path,
230  &path_size),
231  NULL),
233  };
234 
235  if (GNUNET_YES !=
237  rs,
238  i))
239  {
240  GNUNET_break (0);
241  return;
242  }
243  if (0 != (path_size % sizeof(struct GNUNET_DHT_PathElement)))
244  {
245  GNUNET_break (0);
246  path_size = 0;
247  path = NULL;
248  }
249  block.data = data;
250  block.put_path = path;
251  block.put_path_length
252  = path_size / sizeof (struct GNUNET_DHT_PathElement);
253  block.type = (enum GNUNET_BLOCK_Type) type32;
254  block.ro = (enum GNUNET_DHT_RouteOption) bro32;
255  block.key = *hrc->key;
257  "Found result of size %u bytes and type %u in database\n",
258  (unsigned int) block.data_size,
259  (unsigned int) block.type);
260  if ( (NULL != hrc->iter) &&
261  (GNUNET_SYSERR ==
262  hrc->iter (hrc->iter_cls,
263  &block)) )
264  {
266  "Ending iteration (client error)\n");
268  return;
269  }
271  }
272 }
GNUNET_BLOCK_Type
WARNING: This header is generated! In order to add DHT block types, you must register them in GANA,...
uint32_t data
The data value.
static int result
Global testing status.
struct GNUNET_PQ_ResultSpec GNUNET_PQ_result_spec_uint32(const char *name, uint32_t *u32)
uint32_t expected.
#define GNUNET_PQ_result_spec_auto_from_type(name, dst)
We expect a fixed-size result, with size determined by the type of * dst
struct GNUNET_PQ_ResultSpec GNUNET_PQ_result_spec_allow_null(struct GNUNET_PQ_ResultSpec rs, bool *is_null)
Allow NULL value to be found in the database for the given value.
struct GNUNET_PQ_ResultSpec GNUNET_PQ_result_spec_absolute_time(const char *name, struct GNUNET_TIME_Absolute *at)
Absolute time expected.
struct GNUNET_PQ_ResultSpec GNUNET_PQ_result_spec_variable_size(const char *name, void **dst, size_t *sptr)
Variable-size result expected.
void GNUNET_PQ_cleanup_result(struct GNUNET_PQ_ResultSpec *rs)
Free all memory that was allocated in rs during GNUNET_PQ_extract_result().
Definition: pq.c:139
enum GNUNET_GenericReturnValue GNUNET_PQ_extract_result(PGresult *result, struct GNUNET_PQ_ResultSpec *rs, int row)
Extract results from a query result according to the given specification.
Definition: pq.c:149
#define GNUNET_PQ_result_spec_end
End of result parameter specification.
GNUNET_DHT_RouteOption
Options for routing.
@ GNUNET_YES
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur.
@ GNUNET_ERROR_TYPE_DEBUG
#define LOG(kind,...)
Information about a block stored in the datacache.
Description of a DB result cell.
Closure for handle_results.
void * iter_cls
Closure for iter.
const struct GNUNET_HashCode * key
Key used.
GNUNET_DATACACHE_Iterator iter
Function to call on each result, may be NULL.

References GNUNET_DATACACHE_Block::data, data, GNUNET_DATACACHE_Block::data_size, GNUNET_DATACACHE_Block::expiration_time, GNUNET_break, GNUNET_ERROR_TYPE_DEBUG, GNUNET_PQ_cleanup_result(), GNUNET_PQ_extract_result(), GNUNET_PQ_result_spec_absolute_time(), GNUNET_PQ_result_spec_allow_null(), GNUNET_PQ_result_spec_auto_from_type, GNUNET_PQ_result_spec_end, GNUNET_PQ_result_spec_uint32(), GNUNET_PQ_result_spec_variable_size(), GNUNET_SYSERR, GNUNET_YES, HandleResultContext::iter, HandleResultContext::iter_cls, HandleResultContext::key, GNUNET_DATACACHE_Block::key, LOG, GNUNET_DATACACHE_Block::put_path, GNUNET_DATACACHE_Block::put_path_length, result, GNUNET_DATACACHE_Block::ro, GNUNET_DATACACHE_Block::trunc_peer, and GNUNET_DATACACHE_Block::type.

Referenced by postgres_plugin_del().

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◆ postgres_plugin_get()

static unsigned int postgres_plugin_get ( void *  cls,
const struct GNUNET_HashCode key,
enum GNUNET_BLOCK_Type  type,
GNUNET_DATACACHE_Iterator  iter,
void *  iter_cls 
)
static

Iterate over the results for a particular key in the datastore.

Parameters
clsclosure (our struct Plugin)
keykey to look for
typeentries of which type are relevant?
itermaybe NULL (to just count)
iter_clsclosure for iter
Returns
the number of results found

Definition at line 287 of file plugin_datacache_postgres.c.

292 {
293  struct Plugin *plugin = cls;
294  uint32_t type32 = (uint32_t) type;
295  struct GNUNET_TIME_Absolute now = { 0 };
296  struct GNUNET_PQ_QueryParam paramk[] = {
300  };
301  struct GNUNET_PQ_QueryParam paramkt[] = {
306  };
308  struct HandleResultContext hr_ctx;
309 
310  now = GNUNET_TIME_absolute_get ();
311  hr_ctx.iter = iter;
312  hr_ctx.iter_cls = iter_cls;
313  hr_ctx.key = key;
315  (0 == type) ? "getk" : "getkt",
316  (0 == type) ? paramk : paramkt,
318  &hr_ctx);
319  if (res < 0)
320  return 0;
321  return res;
322 }
static int res
struct GNUNET_HashCode key
The key used in the DHT.
enum GNUNET_DB_QueryStatus GNUNET_PQ_eval_prepared_multi_select(struct GNUNET_PQ_Context *db, const char *statement_name, const struct GNUNET_PQ_QueryParam *params, GNUNET_PQ_PostgresResultHandler rh, void *rh_cls)
Execute a named prepared statement that is a SELECT statement which may return multiple results in co...
Definition: pq_eval.c:165
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_get(void)
Get the current time.
Definition: time.c:111
static void handle_results(void *cls, PGresult *result, unsigned int num_results)
Function to be called with the results of a SELECT statement that has returned num_results results.
Time for absolute times used by GNUnet, in microseconds.
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model

Referenced by libgnunet_plugin_datacache_postgres_init().

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◆ postgres_plugin_del()

static enum GNUNET_GenericReturnValue postgres_plugin_del ( void *  cls)
static

Delete the entry with the lowest expiration value from the datacache right now.

Parameters
clsclosure (our struct Plugin)
Returns
GNUNET_OK on success, GNUNET_SYSERR on error

Definition at line 287 of file plugin_datacache_postgres.c.

334 {
335  struct Plugin *plugin = cls;
336  struct GNUNET_PQ_QueryParam pempty[] = {
338  };
339  uint32_t size;
340  uint64_t oid;
341  struct GNUNET_HashCode key;
342  struct GNUNET_PQ_ResultSpec rs[] = {
344  &size),
346  &oid),
348  &key),
350  };
352  struct GNUNET_PQ_QueryParam dparam[] = {
355  };
356  struct GNUNET_TIME_Absolute now;
357  struct GNUNET_PQ_QueryParam xparam[] = {
360  };
361 
362  now = GNUNET_TIME_absolute_get ();
364  "getex",
365  xparam,
366  rs);
367  if (0 >= res)
369  "getm",
370  pempty,
371  rs);
372  if (0 > res)
373  return GNUNET_SYSERR;
375  {
376  /* no result */
378  "Ending iteration (no more results)\n");
379  return 0;
380  }
382  "delrow",
383  dparam);
384  if (0 > res)
385  {
387  return GNUNET_SYSERR;
388  }
389  plugin->num_items--;
390  plugin->env->delete_notify (plugin->env->cls,
391  &key,
392  size + OVERHEAD);
394  return GNUNET_OK;
395 }
@ GNUNET_DB_STATUS_SUCCESS_NO_RESULTS
The transaction succeeded, but yielded zero results.
Definition: gnunet_db_lib.h:55
struct GNUNET_PQ_QueryParam GNUNET_PQ_query_param_uint64(const uint64_t *x)
Generate query parameter for an uint16_t in host byte order.
enum GNUNET_DB_QueryStatus GNUNET_PQ_eval_prepared_singleton_select(struct GNUNET_PQ_Context *db, const char *statement_name, const struct GNUNET_PQ_QueryParam *params, struct GNUNET_PQ_ResultSpec *rs)
Execute a named prepared statement that is a SELECT statement which must return a single result in co...
Definition: pq_eval.c:199
struct GNUNET_PQ_ResultSpec GNUNET_PQ_result_spec_uint64(const char *name, uint64_t *u64)
uint64_t expected.
uint32_t oid
Definition: gnunet_pq_lib.h:2
static unsigned int size
Size of the "table".
Definition: peer.c:68
A 512-bit hashcode.

References GNUNET_PQ_eval_prepared_multi_select(), GNUNET_PQ_query_param_absolute_time(), GNUNET_PQ_query_param_auto_from_type, GNUNET_PQ_query_param_end, GNUNET_PQ_query_param_uint32(), GNUNET_TIME_absolute_get(), handle_results(), HandleResultContext::iter, HandleResultContext::iter_cls, HandleResultContext::key, key, plugin, res, and type.

Referenced by libgnunet_plugin_datacache_postgres_init().

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◆ extract_result_cb()

static void extract_result_cb ( void *  cls,
PGresult *  result,
unsigned int  num_results 
)
static

Function to be called with the results of a SELECT statement that has returned num_results results.

Calls the iter from cls for each result.

Parameters
clsclosure with the struct ExtractResultContext
resultthe postgres result
num_resultsthe number of results in result

Definition at line 425 of file plugin_datacache_postgres.c.

428 {
429  struct ExtractResultContext *erc = cls;
430 
431  if (NULL == erc->iter)
432  return;
433  for (unsigned int i = 0; i < num_results; i++)
434  {
435  uint32_t type32;
436  uint32_t bro32;
437  struct GNUNET_DATACACHE_Block block;
438  void *data;
439  void *path;
440  size_t path_size;
441  struct GNUNET_PQ_ResultSpec rs[] = {
442  GNUNET_PQ_result_spec_absolute_time ("expiration_time",
443  &block.expiration_time),
445  &type32),
447  &bro32),
449  &data,
450  &block.data_size),
452  &block.trunc_peer),
454  &path,
455  &path_size),
457  &block.key),
459  };
460 
461  if (GNUNET_YES !=
463  rs,
464  i))
465  {
466  GNUNET_break (0);
467  return;
468  }
469  if (0 != (path_size % sizeof(struct GNUNET_DHT_PathElement)))
470  {
471  GNUNET_break (0);
472  path_size = 0;
473  path = NULL;
474  }
475  block.type = (enum GNUNET_BLOCK_Type) type32;
476  block.ro = (enum GNUNET_DHT_RouteOption) bro32;
477  block.data = data;
478  block.put_path = path;
479  block.put_path_length = path_size / sizeof (struct GNUNET_DHT_PathElement);
481  "Found result of size %u bytes and type %u in database\n",
482  (unsigned int) block.data_size,
483  (unsigned int) block.type);
484  if ( (NULL != erc->iter) &&
485  (GNUNET_SYSERR ==
486  erc->iter (erc->iter_cls,
487  &block)) )
488  {
490  "Ending iteration (client error)\n");
492  break;
493  }
495  }
496 }
Closure for extract_result_cb.
void * iter_cls
Closure for iter.
GNUNET_DATACACHE_Iterator iter
Function to call for each result found.

References GNUNET_DATACACHE_Block::data, data, GNUNET_DATACACHE_Block::data_size, GNUNET_DATACACHE_Block::expiration_time, GNUNET_break, GNUNET_ERROR_TYPE_DEBUG, GNUNET_PQ_cleanup_result(), GNUNET_PQ_extract_result(), GNUNET_PQ_result_spec_absolute_time(), GNUNET_PQ_result_spec_auto_from_type, GNUNET_PQ_result_spec_end, GNUNET_PQ_result_spec_uint32(), GNUNET_PQ_result_spec_variable_size(), GNUNET_SYSERR, GNUNET_YES, ExtractResultContext::iter, ExtractResultContext::iter_cls, GNUNET_DATACACHE_Block::key, LOG, GNUNET_DATACACHE_Block::put_path, GNUNET_DATACACHE_Block::put_path_length, result, GNUNET_DATACACHE_Block::ro, GNUNET_DATACACHE_Block::trunc_peer, and GNUNET_DATACACHE_Block::type.

Referenced by postgres_plugin_get_closest().

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◆ postgres_plugin_get_closest()

static unsigned int postgres_plugin_get_closest ( void *  cls,
const struct GNUNET_HashCode key,
enum GNUNET_BLOCK_Type  type,
unsigned int  num_results,
GNUNET_DATACACHE_Iterator  iter,
void *  iter_cls 
)
static

Iterate over the results that are "close" to a particular key in the datacache.

"close" is defined as numerically larger than key (when interpreted as a circular address space), with small distance.

Parameters
clsclosure (internal context for the plugin)
keyarea of the keyspace to look into
typedesired block type for the replies
num_resultsnumber of results that should be returned to iter
itermaybe NULL (to just count)
iter_clsclosure for iter
Returns
the number of results found

Definition at line 514 of file plugin_datacache_postgres.c.

520 {
521  struct Plugin *plugin = cls;
522  uint32_t num_results32 = (uint32_t) num_results;
523  uint32_t type32 = (uint32_t) type;
524  struct GNUNET_TIME_Absolute now;
525  struct GNUNET_PQ_QueryParam params[] = {
529  GNUNET_PQ_query_param_uint32 (&num_results32),
531  };
533  struct ExtractResultContext erc;
534 
535  erc.iter = iter;
536  erc.iter_cls = iter_cls;
537  now = GNUNET_TIME_absolute_get ();
539  "get_closest",
540  params,
542  &erc);
543  if (0 > res)
544  {
546  "Ending iteration (postgres error)\n");
547  return 0;
548  }
550  {
551  /* no result */
553  "Ending iteration (no more results)\n");
554  return 0;
555  }
556  return res;
557 }
static void extract_result_cb(void *cls, PGresult *result, unsigned int num_results)
Function to be called with the results of a SELECT statement that has returned num_results results.

References extract_result_cb(), GNUNET_DB_STATUS_SUCCESS_NO_RESULTS, GNUNET_ERROR_TYPE_DEBUG, GNUNET_PQ_eval_prepared_multi_select(), GNUNET_PQ_query_param_absolute_time(), GNUNET_PQ_query_param_auto_from_type, GNUNET_PQ_query_param_end, GNUNET_PQ_query_param_uint32(), GNUNET_TIME_absolute_get(), ExtractResultContext::iter, ExtractResultContext::iter_cls, key, LOG, plugin, res, and type.

Referenced by libgnunet_plugin_datacache_postgres_init().

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◆ libgnunet_plugin_datacache_postgres_init()

void* libgnunet_plugin_datacache_postgres_init ( void *  cls)

Entry point for the plugin.

Parameters
clsclosure (the struct GNUNET_DATACACHE_PluginEnvironmnet)
Returns
the plugin's closure (our struct Plugin)

Definition at line 567 of file plugin_datacache_postgres.c.

568 {
571  struct Plugin *plugin;
572 
573  plugin = GNUNET_new (struct Plugin);
574  plugin->env = env;
575 
577  {
579  return NULL;
580  }
581 
583  api->cls = plugin;
584  api->get = &postgres_plugin_get;
585  api->put = &postgres_plugin_put;
586  api->del = &postgres_plugin_del;
587  api->get_closest = &postgres_plugin_get_closest;
589  "Postgres datacache running\n");
590  return api;
591 }
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
@ GNUNET_ERROR_TYPE_INFO
#define GNUNET_new(type)
Allocate a struct or union of the given type.
#define GNUNET_free(ptr)
Wrapper around free.
static ssize_t postgres_plugin_put(void *cls, uint32_t prox, const struct GNUNET_DATACACHE_Block *block)
Store an item in the datastore.
static enum GNUNET_GenericReturnValue postgres_plugin_del(void *cls)
Delete the entry with the lowest expiration value from the datacache right now.
static enum GNUNET_GenericReturnValue init_connection(struct Plugin *plugin)
Get a database handle.
static unsigned int postgres_plugin_get(void *cls, const struct GNUNET_HashCode *key, enum GNUNET_BLOCK_Type type, GNUNET_DATACACHE_Iterator iter, void *iter_cls)
Iterate over the results for a particular key in the datastore.
static unsigned int postgres_plugin_get_closest(void *cls, const struct GNUNET_HashCode *key, enum GNUNET_BLOCK_Type type, unsigned int num_results, GNUNET_DATACACHE_Iterator iter, void *iter_cls)
Iterate over the results that are "close" to a particular key in the datacache.
void * cls
Closure for all of the callbacks.
The datastore service will pass a pointer to a struct of this type as the first and only argument to ...
void * cls
Closure to use for callbacks.
struct returned by the initialization function of the plugin
struct GNUNET_BLOCK_PluginFunctions * api
Plugin API.
Definition: block.c:47

References Plugin::api, GNUNET_BLOCK_PluginFunctions::cls, GNUNET_DATACACHE_PluginEnvironment::cls, env, GNUNET_ERROR_TYPE_INFO, GNUNET_free, GNUNET_new, GNUNET_OK, init_connection(), LOG, plugin, postgres_plugin_del(), postgres_plugin_get(), postgres_plugin_get_closest(), and postgres_plugin_put().

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◆ libgnunet_plugin_datacache_postgres_done()

void* libgnunet_plugin_datacache_postgres_done ( void *  cls)

Exit point from the plugin.

Parameters
clsclosure (our struct Plugin)
Returns
NULL

Definition at line 601 of file plugin_datacache_postgres.c.

602 {
604  struct Plugin *plugin = api->cls;
605 
608  "datacache-drop"));
611  GNUNET_free (api);
612  return NULL;
613 }
void GNUNET_PQ_disconnect(struct GNUNET_PQ_Context *db)
Disconnect from the database, destroying the prepared statements and releasing other associated resou...
Definition: pq_connect.c:684
enum GNUNET_GenericReturnValue GNUNET_PQ_exec_sql(struct GNUNET_PQ_Context *db, const char *buf)
Execute SQL statements from buf against db.
Definition: pq_connect.c:144
void * cls
Closure to pass to all plugin functions.

References Plugin::api, GNUNET_BLOCK_PluginFunctions::cls, GNUNET_DATACACHE_PluginFunctions::cls, GNUNET_break, GNUNET_free, GNUNET_OK, GNUNET_PQ_disconnect(), GNUNET_PQ_exec_sql(), and plugin.

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