src/SDL_log.c

/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2024 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/
#include "SDL_internal.h"

#if defined(SDL_PLATFORM_WIN32) || defined(SDL_PLATFORM_WINRT) || defined(SDL_PLATFORM_GDK)
#include "core/windows/SDL_windows.h"
#endif

/* Simple log messages in SDL */

#include "SDL_log_c.h"

#ifdef HAVE_STDIO_H
#include <stdio.h>
#endif

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

#include "stdlib/SDL_vacopy.h"

/* The size of the stack buffer to use for rendering log messages. */
#define SDL_MAX_LOG_MESSAGE_STACK 256

#define DEFAULT_CATEGORY -1

typedef struct SDL_LogLevel
{
    int category;
    SDL_LogPriority priority;
    struct SDL_LogLevel *next;
} SDL_LogLevel;

/* The default log output function */
static void SDLCALL SDL_LogOutput(void *userdata, int category, SDL_LogPriority priority, const char *message);

static SDL_LogLevel *SDL_loglevels;
static SDL_bool SDL_forced_priority = SDL_FALSE;
static SDL_LogPriority SDL_forced_priority_level;
static SDL_LogOutputFunction SDL_log_function = SDL_LogOutput;
static void *SDL_log_userdata = NULL;
static SDL_Mutex *log_function_mutex = NULL;

#ifdef HAVE_GCC_DIAGNOSTIC_PRAGMA
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-variable"
#endif

/* If this list changes, update the documentation for SDL_HINT_LOGGING */
static const char *SDL_priority_prefixes[] = {
    NULL,
    "VERBOSE",
    "DEBUG",
    "INFO",
    "WARN",
    "ERROR",
    "CRITICAL"
};
SDL_COMPILE_TIME_ASSERT(priority_prefixes, SDL_arraysize(SDL_priority_prefixes) == SDL_NUM_LOG_PRIORITIES);

/* If this list changes, update the documentation for SDL_HINT_LOGGING */
static const char *SDL_category_prefixes[] = {
    "APP",
    "ERROR",
    "ASSERT",
    "SYSTEM",
    "AUDIO",
    "VIDEO",
    "RENDER",
    "INPUT",
    "TEST"
};
SDL_COMPILE_TIME_ASSERT(category_prefixes, SDL_arraysize(SDL_category_prefixes) == SDL_LOG_CATEGORY_RESERVED1);

#ifdef HAVE_GCC_DIAGNOSTIC_PRAGMA
#pragma GCC diagnostic pop
#endif

#ifdef SDL_PLATFORM_ANDROID
static int SDL_android_priority[SDL_NUM_LOG_PRIORITIES] = {
    ANDROID_LOG_UNKNOWN,
    ANDROID_LOG_VERBOSE,
    ANDROID_LOG_DEBUG,
    ANDROID_LOG_INFO,
    ANDROID_LOG_WARN,
    ANDROID_LOG_ERROR,
    ANDROID_LOG_FATAL
};
#endif /* SDL_PLATFORM_ANDROID */

void SDL_InitLog(void)
{
    if (!log_function_mutex) {
        /* if this fails we'll try to continue without it. */
        log_function_mutex = SDL_CreateMutex();
    }
}

void SDL_QuitLog(void)
{
    SDL_LogResetPriorities();
    if (log_function_mutex) {
        SDL_DestroyMutex(log_function_mutex);
        log_function_mutex = NULL;
    }
}

void SDL_LogSetAllPriority(SDL_LogPriority priority)
{
    SDL_LogLevel *entry;

    for (entry = SDL_loglevels; entry; entry = entry->next) {
        entry->priority = priority;
    }

    SDL_forced_priority = SDL_TRUE;
    SDL_forced_priority_level = priority;
}

void SDL_LogSetPriority(int category, SDL_LogPriority priority)
{
    SDL_LogLevel *entry;

    for (entry = SDL_loglevels; entry; entry = entry->next) {
        if (entry->category == category) {
            entry->priority = priority;
            return;
        }
    }

    /* Create a new entry */
    entry = (SDL_LogLevel *)SDL_malloc(sizeof(*entry));
    if (entry) {
        entry->category = category;
        entry->priority = priority;
        entry->next = SDL_loglevels;
        SDL_loglevels = entry;
    }
}

static SDL_bool SDL_ParseLogCategory(const char *string, size_t length, int *category)
{
    int i;

    if (SDL_isdigit(*string)) {
        *category = SDL_atoi(string);
        return SDL_TRUE;
    }

    if (*string == '*') {
        *category = DEFAULT_CATEGORY;
        return SDL_TRUE;
    }

    for (i = 0; i < SDL_arraysize(SDL_category_prefixes); ++i) {
        if (SDL_strncasecmp(string, SDL_category_prefixes[i], length) == 0) {
            *category = i;
            return SDL_TRUE;
        }
    }
    return SDL_FALSE;
}

static SDL_bool SDL_ParseLogPriority(const char *string, size_t length, SDL_LogPriority *priority)
{
    int i;

    if (SDL_isdigit(*string)) {
        i = SDL_atoi(string);
        if (i == 0) {
            /* 0 has a special meaning of "disable this category" */
            *priority = SDL_NUM_LOG_PRIORITIES;
            return SDL_TRUE;
        }
        if (i >= SDL_LOG_PRIORITY_VERBOSE && i < SDL_NUM_LOG_PRIORITIES) {
            *priority = (SDL_LogPriority)i;
            return SDL_TRUE;
        }
        return SDL_FALSE;
    }

    if (SDL_strncasecmp(string, "quiet", length) == 0) {
        *priority = SDL_NUM_LOG_PRIORITIES;
        return SDL_TRUE;
    }

    for (i = SDL_LOG_PRIORITY_VERBOSE; i < SDL_NUM_LOG_PRIORITIES; ++i) {
        if (SDL_strncasecmp(string, SDL_priority_prefixes[i], length) == 0) {
            *priority = (SDL_LogPriority)i;
            return SDL_TRUE;
        }
    }
    return SDL_FALSE;
}

static SDL_bool SDL_ParseLogCategoryPriority(const char *hint, int category, SDL_LogPriority *priority)
{
    const char *name, *next;
    int current_category;

    if (category == DEFAULT_CATEGORY && SDL_strchr(hint, '=') == NULL) {
        return SDL_ParseLogPriority(hint, SDL_strlen(hint), priority);
    }

    for (name = hint; name; name = next) {
        const char *sep = SDL_strchr(name, '=');
        if (!sep) {
            break;
        }
        next = SDL_strchr(sep, ',');
        if (next) {
            ++next;
        }

        if (SDL_ParseLogCategory(name, (sep - name), &current_category)) {
            if (current_category == category) {
                const char *value = sep + 1;
                size_t len;
                if (next) {
                    len = (next - value - 1);
                } else {
                    len = SDL_strlen(value);
                }
                return SDL_ParseLogPriority(value, len, priority);
            }
        }
    }
    return SDL_FALSE;
}

static SDL_LogPriority SDL_GetDefaultLogPriority(int category)
{
    const char *hint = SDL_GetHint(SDL_HINT_LOGGING);
    if (hint) {
        SDL_LogPriority priority;

        if (SDL_ParseLogCategoryPriority(hint, category, &priority)) {
            return priority;
        }
        if (SDL_ParseLogCategoryPriority(hint, DEFAULT_CATEGORY, &priority)) {
            return priority;
        }
    }

    switch (category) {
    case SDL_LOG_CATEGORY_APPLICATION:
        return SDL_LOG_PRIORITY_INFO;
    case SDL_LOG_CATEGORY_ASSERT:
        return SDL_LOG_PRIORITY_WARN;
    case SDL_LOG_CATEGORY_TEST:
        return SDL_LOG_PRIORITY_VERBOSE;
    default:
        return SDL_LOG_PRIORITY_ERROR;
    }
}

SDL_LogPriority SDL_LogGetPriority(int category)
{
    SDL_LogLevel *entry;

    for (entry = SDL_loglevels; entry; entry = entry->next) {
        if (entry->category == category) {
            return entry->priority;
        }
    }

    if (SDL_forced_priority) {
        return SDL_forced_priority_level;
    }

    return SDL_GetDefaultLogPriority(category);
}

void SDL_LogResetPriorities(void)
{
    SDL_LogLevel *entry;

    while (SDL_loglevels) {
        entry = SDL_loglevels;
        SDL_loglevels = entry->next;
        SDL_free(entry);
    }
    SDL_forced_priority = SDL_FALSE;
}

void SDL_Log(SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    SDL_LogMessageV(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO, fmt, ap);
    va_end(ap);
}

void SDL_LogVerbose(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    SDL_LogMessageV(category, SDL_LOG_PRIORITY_VERBOSE, fmt, ap);
    va_end(ap);
}

void SDL_LogDebug(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    SDL_LogMessageV(category, SDL_LOG_PRIORITY_DEBUG, fmt, ap);
    va_end(ap);
}

void SDL_LogInfo(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    SDL_LogMessageV(category, SDL_LOG_PRIORITY_INFO, fmt, ap);
    va_end(ap);
}

void SDL_LogWarn(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    SDL_LogMessageV(category, SDL_LOG_PRIORITY_WARN, fmt, ap);
    va_end(ap);
}

void SDL_LogError(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    SDL_LogMessageV(category, SDL_LOG_PRIORITY_ERROR, fmt, ap);
    va_end(ap);
}

void SDL_LogCritical(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    SDL_LogMessageV(category, SDL_LOG_PRIORITY_CRITICAL, fmt, ap);
    va_end(ap);
}

void SDL_LogMessage(int category, SDL_LogPriority priority, SDL_PRINTF_FORMAT_STRING const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    SDL_LogMessageV(category, priority, fmt, ap);
    va_end(ap);
}

#ifdef SDL_PLATFORM_ANDROID
static const char *GetCategoryPrefix(int category)
{
    if (category < SDL_LOG_CATEGORY_RESERVED1) {
        return SDL_category_prefixes[category];
    }
    if (category < SDL_LOG_CATEGORY_CUSTOM) {
        return "RESERVED";
    }
    return "CUSTOM";
}
#endif /* SDL_PLATFORM_ANDROID */

void SDL_LogMessageV(int category, SDL_LogPriority priority, SDL_PRINTF_FORMAT_STRING const char *fmt, va_list ap)
{
    char *message = NULL;
    char stack_buf[SDL_MAX_LOG_MESSAGE_STACK];
    size_t len_plus_term;
    int len;
    va_list aq;

    /* Nothing to do if we don't have an output function */
    if (!SDL_log_function) {
        return;
    }

    /* Make sure we don't exceed array bounds */
    if ((int)priority < 0 || priority >= SDL_NUM_LOG_PRIORITIES) {
        return;
    }

    /* See if we want to do anything with this message */
    if (priority < SDL_LogGetPriority(category)) {
        return;
    }

    if (!log_function_mutex) {
        /* this mutex creation can race if you log from two threads at startup. You should have called SDL_Init first! */
        log_function_mutex = SDL_CreateMutex();
    }

    /* Render into stack buffer */
    va_copy(aq, ap);
    len = SDL_vsnprintf(stack_buf, sizeof(stack_buf), fmt, aq);
    va_end(aq);

    if (len < 0) {
        return;
    }

    /* If message truncated, allocate and re-render */
    if (len >= sizeof(stack_buf) && SDL_size_add_overflow(len, 1, &len_plus_term) == 0) {
        /* Allocate exactly what we need, including the zero-terminator */
        message = (char *)SDL_malloc(len_plus_term);
        if (!message) {
            return;
        }
        va_copy(aq, ap);
        len = SDL_vsnprintf(message, len_plus_term, fmt, aq);
        va_end(aq);
    } else {
        message = stack_buf;
    }

    /* Chop off final endline. */
    if ((len > 0) && (message[len - 1] == '\n')) {
        message[--len] = '\0';
        if ((len > 0) && (message[len - 1] == '\r')) { /* catch "\r\n", too. */
            message[--len] = '\0';
        }
    }

    SDL_LockMutex(log_function_mutex);
    SDL_log_function(SDL_log_userdata, category, priority, message);
    SDL_UnlockMutex(log_function_mutex);

    /* Free only if dynamically allocated */
    if (message != stack_buf) {
        SDL_free(message);
    }
}

#if defined(SDL_PLATFORM_WIN32) && !defined(HAVE_STDIO_H) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK)
/* Flag tracking the attachment of the console: 0=unattached, 1=attached to a console, 2=attached to a file, -1=error */
static int consoleAttached = 0;

/* Handle to stderr output of console. */
static HANDLE stderrHandle = NULL;
#endif

static void SDLCALL SDL_LogOutput(void *userdata, int category, SDL_LogPriority priority,
                                  const char *message)
{
#if defined(SDL_PLATFORM_WIN32) || defined(SDL_PLATFORM_WINRT) || defined(SDL_PLATFORM_GDK)
    /* Way too many allocations here, urgh */
    /* Note: One can't call SDL_SetError here, since that function itself logs. */
    {
        char *output;
        size_t length;
        LPTSTR tstr;
        SDL_bool isstack;

#if !defined(HAVE_STDIO_H) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK)
        BOOL attachResult;
        DWORD attachError;
        DWORD charsWritten;
        DWORD consoleMode;

        /* Maybe attach console and get stderr handle */
        if (consoleAttached == 0) {
            attachResult = AttachConsole(ATTACH_PARENT_PROCESS);
            if (!attachResult) {
                attachError = GetLastError();
                if (attachError == ERROR_INVALID_HANDLE) {
                    /* This is expected when running from Visual Studio */
                    /*OutputDebugString(TEXT("Parent process has no console\r\n"));*/
                    consoleAttached = -1;
                } else if (attachError == ERROR_GEN_FAILURE) {
                    OutputDebugString(TEXT("Could not attach to console of parent process\r\n"));
                    consoleAttached = -1;
                } else if (attachError == ERROR_ACCESS_DENIED) {
                    /* Already attached */
                    consoleAttached = 1;
                } else {
                    OutputDebugString(TEXT("Error attaching console\r\n"));
                    consoleAttached = -1;
                }
            } else {
                /* Newly attached */
                consoleAttached = 1;
            }

            if (consoleAttached == 1) {
                stderrHandle = GetStdHandle(STD_ERROR_HANDLE);

                if (GetConsoleMode(stderrHandle, &consoleMode) == 0) {
                    /* WriteConsole fails if the output is redirected to a file. Must use WriteFile instead. */
                    consoleAttached = 2;
                }
            }
        }
#endif /* !defined(HAVE_STDIO_H) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK) */

        length = SDL_strlen(SDL_priority_prefixes[priority]) + 2 + SDL_strlen(message) + 1 + 1 + 1;
        output = SDL_small_alloc(char, length, &isstack);
        (void)SDL_snprintf(output, length, "%s: %s\r\n", SDL_priority_prefixes[priority], message);
        tstr = WIN_UTF8ToString(output);

        /* Output to debugger */
        OutputDebugString(tstr);

#if !defined(HAVE_STDIO_H) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK)
        /* Screen output to stderr, if console was attached. */
        if (consoleAttached == 1) {
            if (!WriteConsole(stderrHandle, tstr, (DWORD)SDL_tcslen(tstr), &charsWritten, NULL)) {
                OutputDebugString(TEXT("Error calling WriteConsole\r\n"));
                if (GetLastError() == ERROR_NOT_ENOUGH_MEMORY) {
                    OutputDebugString(TEXT("Insufficient heap memory to write message\r\n"));
                }
            }

        } else if (consoleAttached == 2) {
            if (!WriteFile(stderrHandle, output, (DWORD)SDL_strlen(output), &charsWritten, NULL)) {
                OutputDebugString(TEXT("Error calling WriteFile\r\n"));
            }
        }
#endif /* !defined(HAVE_STDIO_H) && !defined(SDL_PLATFORM_WINRT) && !defined(SDL_PLATFORM_GDK) */

        SDL_free(tstr);
        SDL_small_free(output, isstack);
    }
#elif defined(SDL_PLATFORM_ANDROID)
    {
        char tag[32];

        SDL_snprintf(tag, SDL_arraysize(tag), "SDL/%s", GetCategoryPrefix(category));
        __android_log_write(SDL_android_priority[priority], tag, message);
    }
#elif defined(SDL_PLATFORM_APPLE) && (defined(SDL_VIDEO_DRIVER_COCOA) || defined(SDL_VIDEO_DRIVER_UIKIT))
    /* Technically we don't need Cocoa/UIKit, but that's where this function is defined for now.
     */
    extern void SDL_NSLog(const char *prefix, const char *text);
    {
        SDL_NSLog(SDL_priority_prefixes[priority], message);
        return;
    }
#elif defined(SDL_PLATFORM_PSP) || defined(SDL_PLATFORM_PS2)
    {
        FILE *pFile;
        pFile = fopen("SDL_Log.txt", "a");
        if (pFile) {
            (void)fprintf(pFile, "%s: %s\n", SDL_priority_prefixes[priority], message);
            (void)fclose(pFile);
        }
    }
#elif defined(SDL_PLATFORM_VITA)
    {
        FILE *pFile;
        pFile = fopen("ux0:/data/SDL_Log.txt", "a");
        if (pFile) {
            (void)fprintf(pFile, "%s: %s\n", SDL_priority_prefixes[priority], message);
            (void)fclose(pFile);
        }
    }
#elif defined(SDL_PLATFORM_3DS)
    {
        FILE *pFile;
        pFile = fopen("sdmc:/3ds/SDL_Log.txt", "a");
        if (pFile) {
            (void)fprintf(pFile, "%s: %s\n", SDL_priority_prefixes[priority], message);
            (void)fclose(pFile);
        }
    }
#endif
#if defined(HAVE_STDIO_H) && \
    !(defined(SDL_PLATFORM_APPLE) && (defined(SDL_VIDEO_DRIVER_COCOA) || defined(SDL_VIDEO_DRIVER_UIKIT)))
    (void)fprintf(stderr, "%s: %s\n", SDL_priority_prefixes[priority], message);
#endif
}

void SDL_GetLogOutputFunction(SDL_LogOutputFunction *callback, void **userdata)
{
    if (callback) {
        *callback = SDL_log_function;
    }
    if (userdata) {
        *userdata = SDL_log_userdata;
    }
}

void SDL_SetLogOutputFunction(SDL_LogOutputFunction callback, void *userdata)
{
    SDL_log_function = callback;
    SDL_log_userdata = userdata;
}