/*
    Authors:
        Simo Sorce <ssorce@redhat.com>
        Stephen Gallagher <sgallagh@redhat.com>

    Copyright (C) 2009 Red Hat

    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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "config.h"

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

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>

#include "util/util.h"

const char *debug_prg_name = "sssd";

int debug_level = SSSDBG_UNRESOLVED;
int debug_timestamps = SSSDBG_TIMESTAMP_UNRESOLVED;
int debug_microseconds = SSSDBG_MICROSECONDS_UNRESOLVED;
int debug_to_file = 0;
const char *debug_log_file = "sssd";
FILE *debug_file = NULL;

errno_t set_debug_file_from_fd(const int fd)
{
    FILE *dummy;
    errno_t ret;

    errno = 0;
    dummy = fdopen(fd, "a");
    if (dummy == NULL) {
        ret = errno;
        DEBUG(1, ("fdopen failed [%d][%s].\n", ret, strerror(ret)));
        sss_log(SSS_LOG_ERR,
                "Could not open debug file descriptor [%d]. "
                "Debug messages will not be written to the file "
                "for this child process [%s][%s]\n",
                fd, debug_prg_name, strerror(ret));
        return ret;
    }

    debug_file = dummy;

    return EOK;
}

int debug_convert_old_level(int old_level)
{
    if ((old_level != 0) && !(old_level & 0x000F))
        return old_level;

    int new_level = SSSDBG_FATAL_FAILURE;

    if (old_level <= 0)
        return new_level;

    if (old_level >= 1)
        new_level |= SSSDBG_CRIT_FAILURE;

    if (old_level >= 2)
        new_level |= SSSDBG_OP_FAILURE;

    if (old_level >= 3)
        new_level |= SSSDBG_MINOR_FAILURE;

    if (old_level >= 4)
        new_level |= SSSDBG_CONF_SETTINGS;

    if (old_level >= 5)
        new_level |= SSSDBG_FUNC_DATA;

    if (old_level >= 6)
        new_level |= SSSDBG_TRACE_FUNC;

    if (old_level >= 7)
        new_level |= SSSDBG_TRACE_LIBS;

    if (old_level >= 8)
        new_level |= SSSDBG_TRACE_INTERNAL;

    if (old_level >= 9)
        new_level |= SSSDBG_TRACE_ALL;

    return new_level;
}

void debug_fn(const char *format, ...)
{
    va_list ap;

    va_start(ap, format);

    vfprintf(debug_file ? debug_file : stderr, format, ap);
    fflush(debug_file ? debug_file : stderr);

    va_end(ap);
}

int debug_get_level(int old_level)
{
    if ((old_level != 0) && !(old_level & 0x000F))
        return old_level;

    if ((old_level > 9) || (old_level < 0))
        return SSSDBG_FATAL_FAILURE;

    int levels[] = {
        SSSDBG_FATAL_FAILURE,   /* 0 */
        SSSDBG_CRIT_FAILURE,
        SSSDBG_OP_FAILURE,
        SSSDBG_MINOR_FAILURE,
        SSSDBG_CONF_SETTINGS,
        SSSDBG_FUNC_DATA,
        SSSDBG_TRACE_FUNC,
        SSSDBG_TRACE_LIBS,
        SSSDBG_TRACE_INTERNAL,
        SSSDBG_TRACE_ALL        /* 9 */
    };

    return levels[old_level];
}

void ldb_debug_messages(void *context, enum ldb_debug_level level,
                        const char *fmt, va_list ap)
{
    int loglevel = SSSDBG_UNRESOLVED;
    int ret;
    char * message = NULL;

    switch(level) {
    case LDB_DEBUG_FATAL:
        loglevel = SSSDBG_FATAL_FAILURE;
        break;
    case LDB_DEBUG_ERROR:
        loglevel = SSSDBG_CRIT_FAILURE;
        break;
    case LDB_DEBUG_WARNING:
        loglevel = SSSDBG_TRACE_FUNC;
        break;
    case LDB_DEBUG_TRACE:
        loglevel = SSSDBG_TRACE_ALL;
        break;
    }

    ret = vasprintf(&message, fmt, ap);
    if (ret < 0) {
        /* ENOMEM */
        return;
    }

    DEBUG_MSG(loglevel, "ldb", message);

    free(message);
}

int open_debug_file_ex(const char *filename, FILE **filep)
{
    FILE *f = NULL;
    char *logpath;
    const char *log_file;
    mode_t old_umask;
    int ret;
    int debug_fd;
    int flags;

    if (filename == NULL) {
        log_file = debug_log_file;
    } else {
        log_file = filename;
    }

    ret = asprintf(&logpath, "%s/%s.log", LOG_PATH, log_file);
    if (ret == -1) {
        return ENOMEM;
    }

    if (debug_file && !filep) fclose(debug_file);

    old_umask = umask(0177);
    errno = 0;
    f = fopen(logpath, "a");
    if (f == NULL) {
        sss_log(SSS_LOG_EMERG, "Could not open file [%s]. Error: [%d][%s]\n",
                               logpath, errno, strerror(errno));
        free(logpath);
        return EIO;
    }
    umask(old_umask);

    debug_fd = fileno(f);
    if (debug_fd == -1) {
        fclose(f);
        free(logpath);
        return EIO;
    }

    flags = fcntl(debug_fd, F_GETFD, 0);
    (void) fcntl(debug_fd, F_SETFD, flags | FD_CLOEXEC);

    if (filep == NULL) {
        debug_file = f;
    } else {
        *filep = f;
    }
    free(logpath);
    return EOK;
}

int open_debug_file(void)
{
    return open_debug_file_ex(NULL, NULL);
}

int rotate_debug_files(void)
{
    int ret;
    errno_t error;

    if (!debug_to_file) return EOK;

    do {
        error = 0;
        ret = fclose(debug_file);
        if (ret != 0) {
            error = errno;
        }

        /* Check for EINTR, which means we should retry
         * because the system call was interrupted by a
         * signal
         */
    } while (error == EINTR);

    if (error != 0) {
        /* Even if we were unable to close the debug log, we need to make
         * sure that we open up a new one. Log rotation will remove the
         * current file, so all debug messages will be disappearing.
         *
         * We should write an error to the syslog warning of the resource
         * leak and then proceed with opening the new file.
         */
        sss_log(SSS_LOG_ALERT, "Could not close debug file [%s]. [%d][%s]\n",
                               debug_log_file, error, strerror(error));
        sss_log(SSS_LOG_ALERT, "Attempting to open new file anyway. "
                               "Be aware that this is a resource leak\n");
    }

    debug_file = NULL;

    return open_debug_file();
}