portaudio/src/common/pa_debugprint.c

/*
 * $Id: pa_log.c $
 * Portable Audio I/O Library Multi-Host API front end
 * Validate function parameters and manage multiple host APIs.
 *
 * Based on the Open Source API proposed by Ross Bencina
 * Copyright (c) 1999-2006 Ross Bencina, Phil Burk
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/*
 * The text above constitutes the entire PortAudio license; however,
 * the PortAudio community also makes the following non-binding requests:
 *
 * Any person wishing to distribute modifications to the Software is
 * requested to send the modifications to the original developer so that
 * they can be incorporated into the canonical version. It is also
 * requested that these non-binding requests be included along with the
 * license above.
 */

/** @file
 @ingroup common_src

 @brief Implements log function.

    PaUtil_SetLogPrintFunction can be user called to replace the provided
    DefaultLogPrint function, which writes to stderr.
    One can NOT pass var_args across compiler/dll boundaries as it is not
    "byte code/abi portable". So the technique used here is to allocate a local
    a static array, write in it, then callback the user with a pointer to its
    start.
*/

#include <stdio.h>
#include <stdarg.h>

#include "pa_debugprint.h"

// for OutputDebugStringA
#if defined(_MSC_VER) && defined(PA_ENABLE_MSVC_DEBUG_OUTPUT)
    #define WIN32_LEAN_AND_MEAN // exclude rare headers
    #include "windows.h"
#endif

// User callback
static PaUtilLogCallback userCB = NULL;

// Sets user callback
void PaUtil_SetDebugPrintFunction(PaUtilLogCallback cb)
{
    userCB = cb;
}

/*
 If your platform doesn't have vsnprintf, you are stuck with a
 VERY dangerous alternative, vsprintf (with no n)
*/
#if _MSC_VER
    /* Some Windows Mobile SDKs don't define vsnprintf but all define _vsnprintf (hopefully).
       According to MSDN "vsnprintf is identical to _vsnprintf". So we use _vsnprintf with MSC.
    */
    #define VSNPRINTF  _vsnprintf
#else
    #define VSNPRINTF  vsnprintf
#endif

#define PA_LOG_BUF_SIZE 2048

void PaUtil_DebugPrint( const char *format, ... )
{
    // Optional logging into Output console of Visual Studio
#if defined(_MSC_VER) && defined(PA_ENABLE_MSVC_DEBUG_OUTPUT)
    {
        char buf[PA_LOG_BUF_SIZE];
        va_list ap;
        va_start(ap, format);
        VSNPRINTF(buf, sizeof(buf), format, ap);
        buf[sizeof(buf)-1] = 0;
        OutputDebugStringA(buf);
        va_end(ap);
    }
#endif

    // Output to User-Callback
    if (userCB != NULL)
    {
        char strdump[PA_LOG_BUF_SIZE];
        va_list ap;
        va_start(ap, format);
        VSNPRINTF(strdump, sizeof(strdump), format, ap);
        strdump[sizeof(strdump)-1] = 0;
        userCB(strdump);
        va_end(ap);
    }
    else
    // Standard output to stderr
    {
        va_list ap;
        va_start(ap, format);
        vfprintf(stderr, format, ap);
        va_end(ap);
        fflush(stderr);
    }
}