daemon.c

linux下的多线程调试工具

/* Copyright (C) 2004,2005,2006  Bull S.A.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#if HAVE_CONFIG_H
#include <config.h>
#endif

#define _XOPEN_SOURCE 500
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <limits.h>
#include <errno.h>
#include <sys/times.h>
#include <sys/types.h>
#include <sys/wait.h>
#include "daemon.h"
#include "types.h"
#include "write_bin.h"
#include "debug.h"

#define PTT_SIZE (ptt_buf->size_buff)
#define TIMEOUT 0xfffff
#define YIELD_TIMEOUT 10

extern struct ptt_buffer * ptt_buf;

int daemon (ptt_header_t *header,char *binary) {
    unsigned int end_read = 0;
    size_t n;
    int status;
    unsigned int timeout = TIMEOUT;
    int pgid = getpgid (0);
#ifdef PTT_TRACE_INFO
    int nb_yield = 0, nb_loop = 0, nb_wait = 0, buf_per_cent = 0;
    int cur_buf, buf_max = 0;
    long cpu_clock;
    struct tms usage;
#endif /* PTT_TRACE_INFO */

    /* while the user function is running */
    while (waitpid (-pgid, &status, WNOHANG) != -1) {

#ifdef PTT_TRACE_INFO
        nb_loop++;
#endif /* PTT_TRACE_INFO */

        /* when more than half of the array is full, empty it */
        /* problem when back to zero */
        /* if ((ptt_buf->reserved - ptt_buf->beg_read) >= PTT_SIZE/2) */
        if (((ptt_buf->reserved >= ptt_buf->beg_read) &&
            ((ptt_buf->reserved - ptt_buf->beg_read) >= PTT_SIZE/2)) ||
           ((ptt_buf->reserved < ptt_buf->beg_read) &&
            (ptt_buf->reserved + (UINT_MAX - ptt_buf->beg_read) >= PTT_SIZE/2)
           )) {
            /* block writters processes to block reservation in the array */
            ptt_buf->PAUSE = 1;	
            /* wait for the end of the writting and get it */	
            while ((ptt_buf->written != ptt_buf->reserved) && --timeout) {
                if (timeout < (TIMEOUT - YIELD_TIMEOUT)) sched_yield();
#ifdef PTT_TRACE_INFO
                nb_wait++;
#endif /* PTT_TRACE_INFO */
            }
            if (timeout == 0) {
                PTT_TRACE_INTERNALS (PTT_DBG_ERROR,
                                     "the application hanged\n");
                write_bin (binary, header, ptt_buf->beg_read,
                           ptt_buf->reserved);
                close_bin ();
                abort ();
            }
            timeout = TIMEOUT;
            end_read = ptt_buf->written;
            /* unblock writters process */
            ptt_buf->PAUSE = 0;
            /* copy new written data, there are between beg_read and
             * end_read */
            n = write_bin (binary, header, ptt_buf->beg_read, end_read); 
#ifdef PTT_TRACE_INFO
            /* problem when back to zero */
            cur_buf = n * 100.0 / PTT_SIZE;
            if (cur_buf > buf_max)
            buf_max = cur_buf;
            buf_per_cent += cur_buf;
#endif /* PTT_TRACE_INFO */
            ptt_buf->beg_read += n;
        }
        else {
            struct timespec t1 = {0, 1}; /* ms */
            nanosleep (&t1, NULL);
#ifdef PTT_TRACE_INFO
            nb_yield++;
#endif /* PTT_TRACE_INFO */
        }
    }
    
    if (errno != ECHILD) perror ("Waitpid failed %d\n");

#ifdef PTT_TRACE_INFO
    PTT_TRACE_INTERNALS (PTT_DBG_STAT, "Daemon stat : %d loop, %d yield, "
                         "%d wait, %d buffer_write\n", nb_loop, nb_yield,
                         nb_wait, nb_loop-nb_yield);
    PTT_TRACE_INTERNALS (PTT_DBG_STAT, "buffer %f %% max %d %%\n", 
                         (float)buf_per_cent/(nb_loop-nb_yield), buf_max);
#endif /* PTT_TRACE_INFO */
    ptt_buf->current_level = 0;
    n = end_read;

    /* the user function is finished, this is the last trace_point */
    while ((ptt_buf->written != ptt_buf->reserved) && --timeout)
        sched_yield();
    if (!timeout) {
        PTT_TRACE_INTERNALS (PTT_DBG_ERROR, "Timeout : some trace_trace "
                             "were killed (%u<%u)\n", ptt_buf->written,
                             ptt_buf->reserved);
        ptt_buf->written = ptt_buf->reserved;
    }
    end_read = ptt_buf->written;
    if (n != end_read)
        /* copy new written data, there are between beg_read and end_read */
        n = write_bin (binary, header, ptt_buf->beg_read, end_read);
    close_bin ();
        
#ifdef PTT_TRACE_INFO
    cpu_clock = sysconf (_SC_CLK_TCK);
    times (&usage);
    PTT_TRACE_INTERNALS (PTT_DBG_STAT, "Child utime %lu.%.2lu stime "
                         "%lu.%.2lu\n", usage.tms_cutime/cpu_clock,
                         usage.tms_cutime%cpu_clock,
                         usage.tms_cstime/cpu_clock,
                         usage.tms_cstime%cpu_clock);
    PTT_TRACE_INTERNALS (PTT_DBG_STAT, "Daemon utime %lu.%.2lu stime "
                         "%lu.%.2lu\n", usage.tms_utime/cpu_clock,
                         usage.tms_utime%cpu_clock,
                         usage.tms_stime/cpu_clock,
                         usage.tms_stime%cpu_clock);
    PTT_TRACE_INTERNALS (PTT_DBG_STAT, "Tracetrace time %llu cpt %u "
                         "(%f call/s, %f clock/call)\n",
                         ptt_buf->stat_time, ptt_buf->stat_nb_trace,
                         (float)(ptt_buf->stat_nb_trace)/
                         usage.tms_cutime*cpu_clock,
                         (float)(ptt_buf->stat_time)/
                         ptt_buf->stat_nb_trace);
    PTT_TRACE_INTERNALS (PTT_DBG_STAT, "      nb pause %d nb wait %d "
                         "nb async %d\n", ptt_buf->stat_nb_pause,
                         ptt_buf->stat_nb_wait, ptt_buf->stat_async);

#endif /* PTT_TRACE_INFO */

    return status;		
}