messages.c
上传用户:riyaled888
上传日期:2009-03-27
资源大小:7338k
文件大小:17k
- /*****************************************************************************
- * messages.c: messages interface
- * This library provides an interface to the message queue to be used by other
- * modules, especially intf modules. See config.h for output configuration.
- *****************************************************************************
- * Copyright (C) 1998-2004 VideoLAN
- * $Id: messages.c 8905 2004-10-04 13:34:42Z gbazin $
- *
- * Authors: Vincent Seguin <seguin@via.ecp.fr>
- * Samuel Hocevar <sam@zoy.org>
- *
- * 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; either version 2 of the License, or
- * (at your option) any later version.
- *
- * 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, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
- *****************************************************************************/
- /*****************************************************************************
- * Preamble
- *****************************************************************************/
- #include <stdio.h> /* required */
- #include <stdarg.h> /* va_list for BSD */
- #include <stdlib.h> /* malloc() */
- #include <string.h> /* strerror() */
- #include <vlc/vlc.h>
- #ifdef HAVE_FCNTL_H
- # include <fcntl.h> /* O_CREAT, O_TRUNC, O_WRONLY, O_SYNC */
- #endif
- #include <errno.h> /* errno */
- #ifdef HAVE_UNISTD_H
- # include <unistd.h> /* close(), write() */
- #endif
- #include "vlc_interface.h"
- /*****************************************************************************
- * Local macros
- *****************************************************************************/
- #if defined(HAVE_VA_COPY)
- # define vlc_va_copy(dest,src) va_copy(dest,src)
- #elif defined(HAVE___VA_COPY)
- # define vlc_va_copy(dest,src) __va_copy(dest,src)
- #else
- # define vlc_va_copy(dest,src) (dest)=(src)
- #endif
- /*****************************************************************************
- * Local prototypes
- *****************************************************************************/
- static void QueueMsg ( vlc_object_t *, int , const char *,
- const char *, va_list );
- static void FlushMsg ( msg_bank_t * );
- static void PrintMsg ( vlc_object_t *, msg_item_t * );
- /**
- * Initialize messages interface
- *
- * This functions has to be called before any call to other msg_* functions.
- * It set up the locks and the message queue if it is used.
- */
- void __msg_Create( vlc_object_t *p_this )
- {
- /* Message queue initialization */
- vlc_mutex_init( p_this, &p_this->p_libvlc->msg_bank.lock );
- p_this->p_libvlc->msg_bank.b_configured = VLC_FALSE;
- p_this->p_libvlc->msg_bank.b_overflow = VLC_FALSE;
- p_this->p_libvlc->msg_bank.i_start = 0;
- p_this->p_libvlc->msg_bank.i_stop = 0;
- p_this->p_libvlc->msg_bank.i_sub = 0;
- p_this->p_libvlc->msg_bank.pp_sub = NULL;
- #ifdef UNDER_CE
- p_this->p_libvlc->msg_bank.logfile =
- CreateFile( L"vlc-log.txt", GENERIC_WRITE,
- FILE_SHARE_READ|FILE_SHARE_WRITE, NULL,
- CREATE_ALWAYS, 0, NULL );
- SetFilePointer( p_this->p_libvlc->msg_bank.logfile, 0, NULL, FILE_END );
- #endif
- }
- /**
- * Flush the message queue
- */
- void __msg_Flush( vlc_object_t *p_this )
- {
- int i_index;
- vlc_mutex_lock( &p_this->p_libvlc->msg_bank.lock );
- p_this->p_libvlc->msg_bank.b_configured = VLC_TRUE;
- for( i_index = p_this->p_libvlc->msg_bank.i_start;
- i_index != p_this->p_libvlc->msg_bank.i_stop;
- i_index = (i_index+1) % VLC_MSG_QSIZE )
- {
- PrintMsg( p_this, &p_this->p_libvlc->msg_bank.msg[i_index] );
- }
- FlushMsg( &p_this->p_libvlc->msg_bank );
- vlc_mutex_unlock( &p_this->p_libvlc->msg_bank.lock );
- }
- /**
- * Free resources allocated by msg_Create
- *
- * This functions prints all messages remaining in queue, then free all the
- * resources allocated by msg_Create.
- * No other messages interface functions should be called after this one.
- */
- void __msg_Destroy( vlc_object_t *p_this )
- {
- if( p_this->p_libvlc->msg_bank.i_sub )
- {
- msg_Err( p_this, "stale interface subscribers" );
- }
- /* Flush the queue */
- if( !p_this->p_libvlc->msg_bank.b_configured )
- {
- msg_Flush( p_this );
- }
- else
- {
- FlushMsg( &p_this->p_libvlc->msg_bank );
- }
- #ifdef UNDER_CE
- CloseHandle( p_this->p_libvlc->msg_bank.logfile );
- #endif
- /* Destroy lock */
- vlc_mutex_destroy( &p_this->p_libvlc->msg_bank.lock );
- }
- /**
- * Subscribe to the message queue.
- */
- msg_subscription_t *__msg_Subscribe( vlc_object_t *p_this )
- {
- msg_bank_t *p_bank = &p_this->p_libvlc->msg_bank;
- msg_subscription_t *p_sub = malloc( sizeof( msg_subscription_t ) );
- vlc_mutex_lock( &p_bank->lock );
- /* Add subscription to the list */
- INSERT_ELEM( p_bank->pp_sub, p_bank->i_sub, p_bank->i_sub, p_sub );
- p_sub->i_start = p_bank->i_start;
- p_sub->pi_stop = &p_bank->i_stop;
- p_sub->p_msg = p_bank->msg;
- p_sub->p_lock = &p_bank->lock;
- vlc_mutex_unlock( &p_bank->lock );
- return p_sub;
- }
- /**
- * Unsubscribe from the message queue.
- */
- void __msg_Unsubscribe( vlc_object_t *p_this, msg_subscription_t *p_sub )
- {
- msg_bank_t *p_bank = &p_this->p_libvlc->msg_bank;
- int i_index;
- vlc_mutex_lock( &p_bank->lock );
- /* Sanity check */
- if( !p_bank->i_sub )
- {
- msg_Err( p_this, "no subscriber in the list" );
- return;
- }
- /* Look for the appropriate subscription */
- for( i_index = 0; i_index < p_bank->i_sub; i_index++ )
- {
- if( p_bank->pp_sub[ i_index ] == p_sub )
- {
- break;
- }
- }
- if( p_bank->pp_sub[ i_index ] != p_sub )
- {
- msg_Err( p_this, "subscriber not found" );
- vlc_mutex_unlock( &p_bank->lock );
- return;
- }
- /* Remove this subscription */
- REMOVE_ELEM( p_bank->pp_sub, p_bank->i_sub, i_index );
- vlc_mutex_unlock( &p_bank->lock );
- }
- /*****************************************************************************
- * __msg_*: print a message
- *****************************************************************************
- * These functions queue a message for later printing.
- *****************************************************************************/
- void __msg_Generic( vlc_object_t *p_this, int i_type, const char *psz_module,
- const char *psz_format, ... )
- {
- va_list args;
- va_start( args, psz_format );
- QueueMsg( p_this, i_type, psz_module, psz_format, args );
- va_end( args );
- }
- void __msg_GenericVa( vlc_object_t *p_this, int i_type, const char *psz_module,
- const char *psz_format, va_list args )
- {
- QueueMsg( p_this, i_type, psz_module, psz_format, args );
- }
- /* Generic functions used when variadic macros are not available. */
- #define DECLARE_MSG_FN( FN_NAME, FN_TYPE )
- void FN_NAME( vlc_object_t *p_this, const char *psz_format, ... )
- {
- va_list args;
- va_start( args, psz_format );
- QueueMsg( (vlc_object_t *)p_this, FN_TYPE, "unknown",
- psz_format, args );
- va_end( args );
- }
- struct _
- /**
- * Output an informational message.
- * note Do not use this for debug messages
- * see input_AddInfo
- */
- DECLARE_MSG_FN( __msg_Info, VLC_MSG_INFO );
- /**
- * Output an error message.
- */
- DECLARE_MSG_FN( __msg_Err, VLC_MSG_ERR );
- /**
- * Output a waring message
- */
- DECLARE_MSG_FN( __msg_Warn, VLC_MSG_WARN );
- /**
- * Output a debug message
- */
- DECLARE_MSG_FN( __msg_Dbg, VLC_MSG_DBG );
- /**
- * Add a message to a queue
- *
- * This function provides basic functionnalities to other msg_* functions.
- * It adds a message to a queue (after having printed all stored messages if it
- * is full). If the message can't be converted to string in memory, it issues
- * a warning.
- */
- static void QueueMsg( vlc_object_t *p_this, int i_type, const char *psz_module,
- const char *psz_format, va_list _args )
- {
- msg_bank_t * p_bank = &p_this->p_libvlc->msg_bank; /* message bank */
- char * psz_str = NULL; /* formatted message string */
- va_list args;
- msg_item_t * p_item = NULL; /* pointer to message */
- msg_item_t item; /* message in case of a full queue */
- #if !defined(HAVE_VASPRINTF) || defined(SYS_DARWIN) || defined(SYS_BEOS)
- int i_size = strlen(psz_format) + INTF_MAX_MSG_SIZE;
- #endif
- /*
- * Convert message to string
- */
- #if defined(HAVE_VASPRINTF) && !defined(SYS_DARWIN) && !defined( SYS_BEOS )
- vlc_va_copy( args, _args );
- vasprintf( &psz_str, psz_format, args );
- va_end( args );
- #else
- psz_str = (char*) malloc( i_size * sizeof(char) );
- #endif
- if( psz_str == NULL )
- {
- fprintf( stderr, "main warning: can't store message (%s): ",
- strerror(errno) );
- vlc_va_copy( args, _args );
- vfprintf( stderr, psz_format, args );
- va_end( args );
- fprintf( stderr, "n" );
- return;
- }
- #if !defined(HAVE_VASPRINTF) || defined(SYS_DARWIN) || defined(SYS_BEOS)
- vlc_va_copy( args, _args );
- vsnprintf( psz_str, i_size, psz_format, args );
- va_end( args );
- psz_str[ i_size - 1 ] = 0; /* Just in case */
- #endif
- /* Put message in queue */
- vlc_mutex_lock( &p_bank->lock );
- /* Check there is room in the queue for our message */
- if( p_bank->b_overflow )
- {
- FlushMsg( p_bank );
- if( ((p_bank->i_stop - p_bank->i_start + 1) % VLC_MSG_QSIZE) == 0 )
- {
- /* Still in overflow mode, print from a dummy item */
- p_item = &item;
- }
- else
- {
- /* Pheeew, at last, there is room in the queue! */
- p_bank->b_overflow = VLC_FALSE;
- }
- }
- else if( ((p_bank->i_stop - p_bank->i_start + 2) % VLC_MSG_QSIZE) == 0 )
- {
- FlushMsg( p_bank );
- if( ((p_bank->i_stop - p_bank->i_start + 2) % VLC_MSG_QSIZE) == 0 )
- {
- p_bank->b_overflow = VLC_TRUE;
- /* Put the overflow message in the queue */
- p_item = p_bank->msg + p_bank->i_stop;
- p_bank->i_stop = (p_bank->i_stop + 1) % VLC_MSG_QSIZE;
- p_item->i_type = VLC_MSG_WARN;
- p_item->i_object_id = p_this->i_object_id;
- p_item->i_object_type = p_this->i_object_type;
- p_item->psz_module = strdup( "message" );
- p_item->psz_msg = strdup( "message queue overflowed" );
- PrintMsg( p_this, p_item );
- /* We print from a dummy item */
- p_item = &item;
- }
- }
- if( !p_bank->b_overflow )
- {
- /* Put the message in the queue */
- p_item = p_bank->msg + p_bank->i_stop;
- p_bank->i_stop = (p_bank->i_stop + 1) % VLC_MSG_QSIZE;
- }
- /* Fill message information fields */
- p_item->i_type = i_type;
- p_item->i_object_id = p_this->i_object_id;
- p_item->i_object_type = p_this->i_object_type;
- p_item->psz_module = strdup( psz_module );
- p_item->psz_msg = psz_str;
- PrintMsg( p_this, p_item );
- if( p_bank->b_overflow )
- {
- free( p_item->psz_module );
- free( p_item->psz_msg );
- }
- vlc_mutex_unlock( &p_bank->lock );
- }
- /* following functions are local */
- /*****************************************************************************
- * FlushMsg
- *****************************************************************************
- * Print all messages remaining in queue. MESSAGE QUEUE MUST BE LOCKED, since
- * this function does not check the lock.
- *****************************************************************************/
- static void FlushMsg ( msg_bank_t *p_bank )
- {
- int i_index, i_start, i_stop;
- /* Only flush the queue if it has been properly configured */
- if( !p_bank->b_configured )
- {
- return;
- }
- /* Get the maximum message index that can be freed */
- i_stop = p_bank->i_stop;
- /* Check until which value we can free messages */
- for( i_index = 0; i_index < p_bank->i_sub; i_index++ )
- {
- i_start = p_bank->pp_sub[ i_index ]->i_start;
- /* If this subscriber is late, we don't free messages before
- * his i_start value, otherwise he'll miss messages */
- if( ( i_start < i_stop
- && (p_bank->i_stop <= i_start || i_stop <= p_bank->i_stop) )
- || ( i_stop < i_start
- && (i_stop <= p_bank->i_stop && p_bank->i_stop <= i_start) ) )
- {
- i_stop = i_start;
- }
- }
- /* Free message data */
- for( i_index = p_bank->i_start;
- i_index != i_stop;
- i_index = (i_index+1) % VLC_MSG_QSIZE )
- {
- free( p_bank->msg[i_index].psz_msg );
- free( p_bank->msg[i_index].psz_module );
- }
- /* Update the new start value */
- p_bank->i_start = i_index;
- }
- /*****************************************************************************
- * PrintMsg: output a message item to stderr
- *****************************************************************************
- * Print a message to stderr, with colour formatting if needed.
- *****************************************************************************/
- static void PrintMsg ( vlc_object_t * p_this, msg_item_t * p_item )
- {
- # define COL(x) "