view src/SDL_error.c @ 5082:de59e0218aa2

Fixed bug #1011 Daniel Ellis 2010-06-25 15:20:31 PDT SDL based applications sometimes display the wrong application name in the Sound Preferences dialog when using pulseaudio. I can see from the code that the SDL pulse module is initiating a new pulse audio context and passing an application name using the function get_progname(). The get_progname() function returns the name of the current process. However, the process name is often not a suitable name to use. For example, the OpenShot video editor is a python application, and so "python" is displayed in the Sound Preferences window (see Bug #596504), when it should be displaying "OpenShot". PulseAudio allows applications to specify the application name, either at the time the context is created (as SDL does currently), or by special environment variables (see http://www.pulseaudio.org/wiki/ApplicationProperties). If no name is specified, then pulseaudio will determine the name based on the process. If you specify the application name when initiating the pulseaudio context, then that will override any application name specified using an environment variable. As libsdl is a library, I believe the solution is for libsdl to not specify any application name when initiating a pulseaudio context, which will enable applications to specify the application name using environment variables. In the case that the applications do not specify anything, pulseaudio will fall back to using the process name anyway. The attached patch removes the get_progname() function and passes NULL as the application name when creating the pulseaudio context, which fixes the issue.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 23 Jan 2011 21:55:04 -0800
parents b12d76ef05e2
children 2ee8112bfc6b
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2010 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library 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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* Simple error handling in SDL */

#ifdef __ANDROID__
#include <android/log.h>
#endif

#include "SDL_error.h"
#include "SDL_error_c.h"

/*#define DEBUG_ERROR*/

/* Routine to get the thread-specific error variable */
#if SDL_THREADS_DISABLED
/* The default (non-thread-safe) global error variable */
static SDL_error SDL_global_error;
#define SDL_GetErrBuf()	(&SDL_global_error)
#else
extern SDL_error *SDL_GetErrBuf(void);
#endif /* SDL_THREADS_DISABLED */

#define SDL_ERRBUFIZE	1024

/* Private functions */

static const char *
SDL_LookupString(const char *key)
{
    /* FIXME: Add code to lookup key in language string hash-table */
    return key;
}

/* Public functions */

void
SDL_SetError(const char *fmt, ...)
{
    va_list ap;
    SDL_error *error;

    /* Copy in the key, mark error as valid */
    error = SDL_GetErrBuf();
    error->error = 1;
    SDL_strlcpy((char *) error->key, fmt, sizeof(error->key));

    va_start(ap, fmt);
    error->argc = 0;
    while (*fmt) {
        if (*fmt++ == '%') {
            while (*fmt == '.' || (*fmt >= '0' && *fmt <= '9')) {
                ++fmt;
            }
            switch (*fmt++) {
            case 0:            /* Malformed format string.. */
                --fmt;
                break;
            case 'c':
            case 'i':
            case 'd':
            case 'u':
            case 'o':
            case 'x':
            case 'X':
                error->args[error->argc++].value_i = va_arg(ap, int);
                break;
            case 'f':
                error->args[error->argc++].value_f = va_arg(ap, double);
                break;
            case 'p':
                error->args[error->argc++].value_ptr = va_arg(ap, void *);
                break;
            case 's':
                {
                    int i = error->argc;
                    const char *str = va_arg(ap, const char *);
                    if (str == NULL)
                        str = "(null)";
                    SDL_strlcpy((char *) error->args[i].buf, str,
                                ERR_MAX_STRLEN);
                    error->argc++;
                }
                break;
            default:
                break;
            }
            if (error->argc >= ERR_MAX_ARGS) {
                break;
            }
        }
    }
    va_end(ap);

    /* If we are in debug mode, print out an error message */
#ifdef DEBUG_ERROR
    fprintf(stderr, "SDL_SetError: %s\n", SDL_GetError());
#ifdef __ANDROID__
    __android_log_print(ANDROID_LOG_INFO, "SDL", "ERROR: %s", SDL_GetError());
#endif
#endif /* DEBUG_ERROR */
}

/* This function has a bit more overhead than most error functions
   so that it supports internationalization and thread-safe errors.
*/
static char *
SDL_GetErrorMsg(char *errstr, unsigned int maxlen)
{
    SDL_error *error;

    /* Clear the error string */
    *errstr = '\0';
    --maxlen;

    /* Get the thread-safe error, and print it out */
    error = SDL_GetErrBuf();
    if (error->error) {
        const char *fmt;
        char *msg = errstr;
        int len;
        int argi;

        fmt = SDL_LookupString(error->key);
        argi = 0;
        while (*fmt && (maxlen > 0)) {
            if (*fmt == '%') {
                char tmp[32], *spot = tmp;
                *spot++ = *fmt++;
                while ((*fmt == '.' || (*fmt >= '0' && *fmt <= '9'))
                       && spot < (tmp + SDL_arraysize(tmp) - 2)) {
                    *spot++ = *fmt++;
                }
                *spot++ = *fmt++;
                *spot++ = '\0';
                switch (spot[-2]) {
                case '%':
                    *msg++ = '%';
                    maxlen -= 1;
                    break;
                case 'c':
                case 'i':
                case 'd':
                case 'u':
                case 'o':
                case 'x':
                case 'X':
                    len =
                        SDL_snprintf(msg, maxlen, tmp,
                                     error->args[argi++].value_i);
                    msg += len;
                    maxlen -= len;
                    break;
                case 'f':
                    len =
                        SDL_snprintf(msg, maxlen, tmp,
                                     error->args[argi++].value_f);
                    msg += len;
                    maxlen -= len;
                    break;
                case 'p':
                    len =
                        SDL_snprintf(msg, maxlen, tmp,
                                     error->args[argi++].value_ptr);
                    msg += len;
                    maxlen -= len;
                    break;
                case 's':
                    len =
                        SDL_snprintf(msg, maxlen, tmp,
                                     SDL_LookupString(error->args[argi++].
                                                      buf));
                    msg += len;
                    maxlen -= len;
                    break;
                }
            } else {
                *msg++ = *fmt++;
                maxlen -= 1;
            }
        }
        *msg = 0;               /* NULL terminate the string */
    }
    return (errstr);
}

/* Available for backwards compatibility */
const char *
SDL_GetError(void)
{
    static char errmsg[SDL_ERRBUFIZE];

    return SDL_GetErrorMsg(errmsg, SDL_ERRBUFIZE);
}

void
SDL_ClearError(void)
{
    SDL_error *error;

    error = SDL_GetErrBuf();
    error->error = 0;
}

/* Very common errors go here */
void
SDL_Error(SDL_errorcode code)
{
    switch (code) {
    case SDL_ENOMEM:
        SDL_SetError("Out of memory");
        break;
    case SDL_EFREAD:
        SDL_SetError("Error reading from datastream");
        break;
    case SDL_EFWRITE:
        SDL_SetError("Error writing to datastream");
        break;
    case SDL_EFSEEK:
        SDL_SetError("Error seeking in datastream");
        break;
    case SDL_UNSUPPORTED:
        SDL_SetError("That operation is not supported");
        break;
    default:
        SDL_SetError("Unknown SDL error");
        break;
    }
}

#ifdef TEST_ERROR
int
main(int argc, char *argv[])
{
    char buffer[BUFSIZ + 1];

    SDL_SetError("Hi there!");
    printf("Error 1: %s\n", SDL_GetError());
    SDL_ClearError();
    SDL_memset(buffer, '1', BUFSIZ);
    buffer[BUFSIZ] = 0;
    SDL_SetError("This is the error: %s (%f)", buffer, 1.0);
    printf("Error 2: %s\n", SDL_GetError());
    exit(0);
}
#endif

/* vi: set ts=4 sw=4 expandtab: */