/*
 * Copyright (C) 2015 University of Chicago.
 * See COPYRIGHT notice in top-level directory.
 *
 */

#define _GNU_SOURCE
#include "darshan-util-config.h"
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <stdlib.h>
#include <unistd.h>
#include <inttypes.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>

#include "darshan-logutils.h"

/* integer counter name strings for the STDIO module */
#define X(a) #a,
char *stdio_counter_names[] = {
    STDIO_COUNTERS
};

/* floating point counter name strings for the STDIO module */
char *stdio_f_counter_names[] = {
    STDIO_F_COUNTERS
};
#undef X

/* prototypes for each of the STDIO module's logutil functions */
static int darshan_log_get_stdio_record(darshan_fd fd, void* stdio_buf,
    darshan_record_id* rec_id);
static int darshan_log_put_stdio_record(darshan_fd fd, void* stdio_buf, int ver);
static void darshan_log_print_stdio_record(void *file_rec,
    char *file_name, char *mnt_pt, char *fs_type, int ver);
static void darshan_log_print_stdio_description(void);
static void darshan_log_print_stdio_record_diff(void *file_rec1, char *file_name1,
    void *file_rec2, char *file_name2);

/* structure storing each function needed for implementing the darshan
 * logutil interface. these functions are used for reading, writing, and
 * printing module data in a consistent manner.
 */
struct darshan_mod_logutil_funcs stdio_logutils =
{
    .log_get_record = &darshan_log_get_stdio_record,
    .log_put_record = &darshan_log_put_stdio_record,
    .log_print_record = &darshan_log_print_stdio_record,
    .log_print_description = &darshan_log_print_stdio_description,
    .log_print_diff = &darshan_log_print_stdio_record_diff
};

/* retrieve a STDIO record from log file descriptor 'fd', storing the
 * buffer in 'stdio_buf' and the corresponding Darshan record id in
 * 'rec_id'. Return 1 on successful record read, 0 on no more data,
 * and -1 on error.
 */
static int darshan_log_get_stdio_record(darshan_fd fd, void* stdio_buf, 
    darshan_record_id* rec_id)
{
    struct darshan_stdio_record *rec;
    int i;
    int ret;

    /* read a STDIO module record from the darshan log file */
    ret = darshan_log_getmod(fd, DARSHAN_STDIO_MOD, stdio_buf,
        sizeof(struct darshan_stdio_record));
    if(ret < 0)
        return(-1);
    else if(ret < sizeof(struct darshan_stdio_record))
        return(0);
    else
    {
        /* if the read was successful, do any necessary byte-swapping */
        rec = (struct darshan_stdio_record *)stdio_buf;
        if(fd->swap_flag)
        {
            /* swap bytes if necessary */
            DARSHAN_BSWAP64(&rec->f_id);
            DARSHAN_BSWAP64(&rec->rank);
            for(i=0; i<STDIO_NUM_INDICES; i++)
                DARSHAN_BSWAP64(&rec->counters[i]);
            for(i=0; i<STDIO_F_NUM_INDICES; i++)
                DARSHAN_BSWAP64(&rec->fcounters[i]);
        }

        /* set the output record id */
        *rec_id = rec->f_id;
        return(1);
    }
}

/* write the STDIO record stored in 'stdio_buf' to log file descriptor 'fd'.
 * Return 0 on success, -1 on failure
 */
static int darshan_log_put_stdio_record(darshan_fd fd, void* stdio_buf, int ver)
{
    struct darshan_stdio_record *rec = (struct darshan_stdio_record *)stdio_buf;
    int ret;

    /* append STDIO record to darshan log file */
    ret = darshan_log_putmod(fd, DARSHAN_STDIO_MOD, rec,
        sizeof(struct darshan_stdio_record), ver);
    if(ret < 0)
        return(-1);

    return(0);
}

/* print all I/O data record statistics for the given STDIO record */
static void darshan_log_print_stdio_record(void *file_rec, char *file_name,
    char *mnt_pt, char *fs_type, int ver)
{
    int i;
    struct darshan_stdio_record *stdio_rec =
        (struct darshan_stdio_record *)file_rec;

    /* print each of the integer and floating point counters for the STDIO module */
    for(i=0; i<STDIO_NUM_INDICES; i++)
    {
        /* macro defined in darshan-logutils.h */
        DARSHAN_COUNTER_PRINT(darshan_module_names[DARSHAN_STDIO_MOD],
            stdio_rec->rank, stdio_rec->f_id, stdio_counter_names[i],
            stdio_rec->counters[i], file_name, mnt_pt, fs_type);
    }

    for(i=0; i<STDIO_F_NUM_INDICES; i++)
    {
        /* macro defined in darshan-logutils.h */
        DARSHAN_F_COUNTER_PRINT(darshan_module_names[DARSHAN_STDIO_MOD],
            stdio_rec->rank, stdio_rec->f_id, stdio_f_counter_names[i],
            stdio_rec->fcounters[i], file_name, mnt_pt, fs_type);
    }

    return;
}

/* print out a description of the STDIO module record fields */
static void darshan_log_print_stdio_description()
{
    printf("\n# description of STDIO counters:\n");
    printf("#   STDIO_{OPENS|WRITES|READS} are types of operations.\n");
    printf("#   STDIO_BYTES_*: total bytes read and written.\n");
    printf("#   STDIO_MAX_BYTE_*: highest offset byte read and written.\n");
    printf("#   STDIO_F_*_START_TIMESTAMP: timestamp of the first call to that type of function.\n");
    printf("#   STDIO_F_*_END_TIMESTAMP: timestamp of the completion of the last call to that type of function.\n");
    printf("#   STDIO_F_*_TIME: cumulative time spent in different types of functions.\n");

    return;
}

static void darshan_log_print_stdio_record_diff(void *file_rec1, char *file_name1,
    void *file_rec2, char *file_name2)
{
    struct darshan_stdio_record *file1 = (struct darshan_stdio_record *)file_rec1;
    struct darshan_stdio_record *file2 = (struct darshan_stdio_record *)file_rec2;
    int i;

    /* NOTE: we assume that both input records are the same module format version */

    for(i=0; i<STDIO_NUM_INDICES; i++)
    {
        if(!file2)
        {
            printf("- ");
            DARSHAN_COUNTER_PRINT(darshan_module_names[DARSHAN_STDIO_MOD],
                file1->rank, file1->f_id, stdio_counter_names[i],
                file1->counters[i], file_name1, "", "");

        }
        else if(!file1)
        {
            printf("+ ");
            DARSHAN_COUNTER_PRINT(darshan_module_names[DARSHAN_STDIO_MOD],
                file2->rank, file2->f_id, stdio_counter_names[i],
                file2->counters[i], file_name2, "", "");
        }
        else if(file1->counters[i] != file2->counters[i])
        {
            printf("- ");
            DARSHAN_COUNTER_PRINT(darshan_module_names[DARSHAN_STDIO_MOD],
                file1->rank, file1->f_id, stdio_counter_names[i],
                file1->counters[i], file_name1, "", "");
            printf("+ ");
            DARSHAN_COUNTER_PRINT(darshan_module_names[DARSHAN_STDIO_MOD],
                file2->rank, file2->f_id, stdio_counter_names[i],
                file2->counters[i], file_name2, "", "");
        }
    }

    for(i=0; i<STDIO_F_NUM_INDICES; i++)
    {
        if(!file2)
        {
            printf("- ");
            DARSHAN_F_COUNTER_PRINT(darshan_module_names[DARSHAN_STDIO_MOD],
                file1->rank, file1->f_id, stdio_f_counter_names[i],
                file1->fcounters[i], file_name1, "", "");

        }
        else if(!file1)
        {
            printf("+ ");
            DARSHAN_F_COUNTER_PRINT(darshan_module_names[DARSHAN_STDIO_MOD],
                file2->rank, file2->f_id, stdio_f_counter_names[i],
                file2->fcounters[i], file_name2, "", "");
        }
        else if(file1->fcounters[i] != file2->fcounters[i])
        {
            printf("- ");
            DARSHAN_F_COUNTER_PRINT(darshan_module_names[DARSHAN_STDIO_MOD],
                file1->rank, file1->f_id, stdio_f_counter_names[i],
                file1->fcounters[i], file_name1, "", "");
            printf("+ ");
            DARSHAN_F_COUNTER_PRINT(darshan_module_names[DARSHAN_STDIO_MOD],
                file2->rank, file2->f_id, stdio_f_counter_names[i],
                file2->fcounters[i], file_name2, "", "");
        }
    }

    return;
}


/*
 * Local variables:
 *  c-indent-level: 4
 *  c-basic-offset: 4
 * End:
 *
 * vim: ts=8 sts=4 sw=4 expandtab
 */