/* Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; version 2 of the License.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software Foundation,
 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */

#ifndef _SQL_PROFILE_H
#define _SQL_PROFILE_H

class Item;
struct TABLE_LIST;
class THD;
typedef struct st_field_info ST_FIELD_INFO;
typedef struct st_schema_table ST_SCHEMA_TABLE;

extern ST_FIELD_INFO query_profile_statistics_info[];
int fill_query_profile_statistics_info(THD *thd, TABLE_LIST *tables, Item *cond);
int make_profile_table_for_show(THD *thd, ST_SCHEMA_TABLE *schema_table);


#define PROFILE_NONE (uint)0
#define PROFILE_CPU (uint)(1<<0)
#define PROFILE_MEMORY (uint)(1<<1)
#define PROFILE_BLOCK_IO (uint)(1<<2)
#define PROFILE_CONTEXT (uint)(1<<3)
#define PROFILE_PAGE_FAULTS (uint)(1<<4)
#define PROFILE_IPC (uint)(1<<5)
#define PROFILE_SWAPS (uint)(1<<6)
#define PROFILE_SOURCE (uint)(1<<16)
#define PROFILE_ALL (uint)(~0)


#if defined(ENABLED_PROFILING)
#include "sql_priv.h"
#include "unireg.h"

#ifdef HAVE_SYS_RESOURCE_H
#include <sys/resource.h>
#endif


class PROF_MEASUREMENT;
class QUERY_PROFILE;
class PROFILING;


/**
 Implements a persistent FIFO using server List method names. Not
 thread-safe. Intended to be used on thread-local data only. 
*/
template <class T> class Queue
{
private:

 struct queue_item
 {
 T *payload;
 struct queue_item *next, *previous;
 };

 struct queue_item *first, *last;

public:
 Queue()
 {
 elements= 0;
 first= last= NULL;
 }

 void empty()
 {
 struct queue_item *i, *after_i;
 for (i= first; i != NULL; i= after_i)
 {
 after_i= i->next;
 my_free(i);
 }
 elements= 0;
 }

 ulong elements; /* The count of items in the Queue */

 void push_back(T *payload)
 {
 struct queue_item *new_item;

 new_item= (struct queue_item *) my_malloc(sizeof(struct queue_item), MYF(0));

 new_item->payload= payload;

 if (first == NULL)
 first= new_item;
 if (last != NULL)
 {
 DBUG_ASSERT(last->next == NULL);
 last->next= new_item;
 }
 new_item->previous= last;
 new_item->next= NULL;
 last= new_item;

 elements++;
 }

 T *pop()
 {
 struct queue_item *old_item= first;
 T *ret= NULL;

 if (first == NULL)
 {
 DBUG_PRINT("warning", ("tried to pop nonexistent item from Queue"));
 return NULL;
 }

 ret= old_item->payload;
 if (first->next != NULL)
 first->next->previous= NULL;
 else
 last= NULL;
 first= first->next;

 my_free(old_item);
 elements--;

 return ret;
 }

 bool is_empty()
 {
 DBUG_ASSERT(((elements > 0) && (first != NULL)) || ((elements == 0) || (first == NULL)));
 return (elements == 0);
 }

 void *new_iterator()
 {
 return first;
 }

 void *iterator_next(void *current)
 {
 return ((struct queue_item *) current)->next;
 }

 T *iterator_value(void *current)
 {
 return ((struct queue_item *) current)->payload;
 }

};


/**
 A single entry in a single profile.
*/
class PROF_MEASUREMENT
{
 QUERY_PROFILE *profile;

 char *allocated_status_memory;

 void set_label(const char *status_arg, const char *function_arg, 
 const char *file_arg, unsigned int line_arg);
 void clean_up();

public:
 char *status;
#ifdef HAVE_GETRUSAGE
 struct rusage rusage;
#elif defined(_WIN32)
 FILETIME ftKernel, ftUser;
#endif

 char *function;
 char *file;
 unsigned int line;

 ulong m_seq;
 double time_usecs;
 double cpu_time_usecs;
 PROF_MEASUREMENT();
 PROF_MEASUREMENT(QUERY_PROFILE *profile_arg, const char *status_arg);
 PROF_MEASUREMENT(QUERY_PROFILE *profile_arg, const char *status_arg,
 const char *function_arg,
 const char *file_arg, unsigned int line_arg);
 ~PROF_MEASUREMENT();
 void collect();
};


/**
 The full profile for a single query, and includes multiple PROF_MEASUREMENT
 objects.
*/
class QUERY_PROFILE
{
private:
 friend class PROFILING;

 PROFILING *profiling;

 query_id_t profiling_query_id; /* Session-specific id. */
 char *query_source;

 double m_start_time_usecs;
 double m_end_time_usecs;
 ulong m_seq_counter;
 Queue<PROF_MEASUREMENT> entries;


 QUERY_PROFILE(PROFILING *profiling_arg, const char *status_arg);
 ~QUERY_PROFILE();

 void set_query_source(char *query_source_arg, uint query_length_arg);

 /* Add a profile status change to the current profile. */
 void new_status(const char *status_arg,
 const char *function_arg,
 const char *file_arg, unsigned int line_arg);

 /* Reset the contents of this profile entry. */
 void reset();

 /* Show this profile. This is called by PROFILING. */
 bool show(uint options);

public:

 inline PROFILING * get_profiling() { return profiling; };

};


/**
 Profiling state for a single THD; contains multiple QUERY_PROFILE objects.
*/
class PROFILING
{
private:
 friend class PROF_MEASUREMENT;
 friend class QUERY_PROFILE;

 /* 
 Not the system query_id, but a counter unique to profiling. 
 */
 query_id_t profile_id_counter; 
 THD *thd;
 bool keeping;
 bool enabled;

 QUERY_PROFILE *current;
 QUERY_PROFILE *last;
 Queue<QUERY_PROFILE> history;
 
 query_id_t next_profile_id() { return(profile_id_counter++); }

public:
 PROFILING();
 ~PROFILING();
 void set_query_source(char *query_source_arg, uint query_length_arg);

 void start_new_query(const char *initial_state= "starting");

 void discard_current_query();

 void finish_current_query();

 void status_change(const char *status_arg,
 const char *function_arg,
 const char *file_arg, unsigned int line_arg);

 inline void set_thd(THD *thd_arg) { thd= thd_arg; };

 /* SHOW PROFILES */
 bool show_profiles();
 bool enabled_getrusage();

 /* ... from INFORMATION_SCHEMA.PROFILING ... */
 int fill_statistics_info(THD *thd, TABLE_LIST *tables, Item *cond);
 int print_current(IO_CACHE *log_file);
};

# endif /* HAVE_PROFILING */
#endif /* _SQL_PROFILE_H */