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/* Database structures and declarations. |
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* |
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* IRC Services is copyright (c) 1996-2009 Andrew Church. |
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* E-mail: <achurch@achurch.org> |
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* Parts written by Andrew Kempe and others. |
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* This program is free but copyrighted software; see the file GPL.txt for |
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* details. |
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*/ |
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|
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#ifndef DATABASE_H |
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#define DATABASE_H |
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|
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#ifndef MODULES_H |
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# include "modules.h" |
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#endif |
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|
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/*************************************************************************/ |
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|
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/* Type constants for DBField.type */ |
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typedef enum { |
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DBTYPE_INT8, |
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DBTYPE_UINT8, |
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DBTYPE_INT16, |
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DBTYPE_UINT16, |
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DBTYPE_INT32, |
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DBTYPE_UINT32, |
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DBTYPE_TIME, |
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DBTYPE_STRING, |
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DBTYPE_BUFFER, /* Buffer size in DBField.length */ |
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DBTYPE_PASSWORD, |
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} DBType; |
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|
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/* Structure that describes a field of a database table */ |
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typedef struct dbfield_ { |
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const char *name; /* Field name */ |
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DBType type; /* Field type */ |
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int offset; /* Offset to field from start of structure |
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* (use standard `offsetof' macro) */ |
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int length; /* Length of DBTYPE_BUFFER fields */ |
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int load_only; /* If nonzero, field is not saved (use for reading |
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* obsolete fields) */ |
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void (*get)(const void *record, void **value_ret); |
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/* Function to retrieve the field's value when |
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* saving; `value_ret' points to a variable of |
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* the appropriate type (for DBTYPE_STRING, the |
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* string should be malloc'd if not NULL) */ |
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void (*put)(void *record, const void *value); |
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/* Function to set the field's value on load; |
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* `value' points to a variable of the |
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* appropriate type */ |
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} DBField; |
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|
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/* Structure that describes a database table */ |
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typedef struct dbtable_ { |
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const char *name; /* Table name */ |
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DBField *fields; /* Array of fields, terminated with name==NULL */ |
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void *(*newrec)(void); |
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/* Routine to allocate a new record */ |
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void (*freerec)(void *record); |
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/* Routine to free an allocated record (that has |
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* not been inserted into the table) */ |
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void (*insert)(void *record); |
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/* Routine to insert a record (used when loading, |
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* returns nonzero for success or 0 for failure) */ |
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void *(*first)(void), *(*next)(void); |
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/* Routines to iterate through all records (used |
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* when saving) */ |
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int (*postload)(void); |
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/* Routine called after all records have been loaded; |
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* returns nonzero for success or 0 for failure */ |
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} DBTable; |
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|
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/* Container for module-implemented database functions */ |
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typedef struct dbmodule_ { |
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/* Load the given table from permanent storage, returning nonzero for |
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* success, zero for failure. */ |
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int (*load_table)(DBTable *table); |
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/* Save the given table to permanent storage, returning nonzero for |
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* success, zero for failure */ |
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int (*save_table)(DBTable *table); |
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} DBModule; |
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|
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/*************************************************************************/ |
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|
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/* Macro to return a pointer to a field in a record */ |
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#define DB_FIELDPTR(record,field) ((int8 *)(record) + (field)->offset) |
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|
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/*************************************************************************/ |
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|
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/* Initialization/cleanup routines. */ |
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extern int database_init(int ac, char **av); |
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extern void database_cleanup(void); |
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|
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/* Register a new database table. Returns nonzero on success, zero on |
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* error. */ |
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#define register_dbtable(table) _register_dbtable((table), THIS_MODULE) |
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extern int _register_dbtable(DBTable *table, const Module *caller); |
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|
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/* Unregister a database table. Does nothing if the table was not |
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* registered in the first place. */ |
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extern void unregister_dbtable(DBTable *table); |
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|
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/* Save all registered database tables to permanent storage. Returns 1 if |
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* all tables were successfully saved or no tables are registered, 0 if |
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* some tables were successfully saved (but some were not), or -1 if no |
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* tables were successfully saved. */ |
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extern int save_all_dbtables(void); |
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|
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/* Register a database module. Returns nonzero on success, zero on error. |
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* On success, all registered tables which have not already been loaded |
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* will be loaded from permanent storage. Only one database module can be |
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* registered. */ |
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extern int register_dbmodule(DBModule *module); |
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|
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/* Unregister a database module. Does nothing if the module was not |
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* registered in the first place. */ |
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extern void unregister_dbmodule(DBModule *module); |
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|
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/* Read a value from a database field. The value buffer is assumed to be |
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* large enough to hold the retrieved value. */ |
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extern void get_dbfield(const void *record, const DBField *field, |
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void *buffer); |
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|
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/* Store a value to a database field. */ |
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extern void put_dbfield(void *record, const DBField *field, const void *value); |
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|
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/*************************************************************************/ |
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|
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#endif /* DATABASE_H */ |
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|
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/* |
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* Local variables: |
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* c-file-style: "stroustrup" |
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* c-file-offsets: ((case-label . *) (statement-case-intro . *)) |
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* indent-tabs-mode: nil |
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* End: |
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* |
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* vim: expandtab shiftwidth=4: |
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*/ |