darshan-posix.c

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

#define _XOPEN_SOURCE 500
#define _GNU_SOURCE

#include "darshan-runtime-config.h"
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdarg.h>
#include <string.h>
#include <time.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/uio.h>
#include <sys/mman.h>
#include <search.h>
#include <assert.h>
#include <libgen.h>
#include <aio.h>
#include <pthread.h>

#include "utlist.h"
#include "darshan.h"
#include "darshan-dynamic.h"
#include "darshan-dxt.h"

#ifndef HAVE_OFF64_T
typedef int64_t off64_t;
#endif
#ifndef HAVE_AIOCB64
#define aiocb64 aiocb
#endif


DARSHAN_FORWARD_DECL(open, int, (const char *path, int flags, ...));
DARSHAN_FORWARD_DECL(open64, int, (const char *path, int flags, ...));
DARSHAN_FORWARD_DECL(__open_2, int, (const char *path, int oflag));
DARSHAN_FORWARD_DECL(creat, int, (const char* path, mode_t mode));
DARSHAN_FORWARD_DECL(creat64, int, (const char* path, mode_t mode));
DARSHAN_FORWARD_DECL(dup, int, (int oldfd));
DARSHAN_FORWARD_DECL(dup2, int, (int oldfd, int newfd));
DARSHAN_FORWARD_DECL(dup3, int, (int oldfd, int newfd, int flags));
DARSHAN_FORWARD_DECL(fileno, int, (FILE *stream));
DARSHAN_FORWARD_DECL(mkstemp, int, (char *template));
DARSHAN_FORWARD_DECL(mkostemp, int, (char *template, int flags));
DARSHAN_FORWARD_DECL(mkstemps, int, (char *template, int suffixlen));
DARSHAN_FORWARD_DECL(mkostemps, int, (char *template, int suffixlen, int flags));
DARSHAN_FORWARD_DECL(read, ssize_t, (int fd, void *buf, size_t count));
DARSHAN_FORWARD_DECL(write, ssize_t, (int fd, const void *buf, size_t count));
DARSHAN_FORWARD_DECL(pread, ssize_t, (int fd, void *buf, size_t count, off_t offset));
DARSHAN_FORWARD_DECL(pwrite, ssize_t, (int fd, const void *buf, size_t count, off_t offset));
DARSHAN_FORWARD_DECL(pread64, ssize_t, (int fd, void *buf, size_t count, off64_t offset));
DARSHAN_FORWARD_DECL(pwrite64, ssize_t, (int fd, const void *buf, size_t count, off64_t offset));
DARSHAN_FORWARD_DECL(readv, ssize_t, (int fd, const struct iovec *iov, int iovcnt));
DARSHAN_FORWARD_DECL(writev, ssize_t, (int fd, const struct iovec *iov, int iovcnt));
DARSHAN_FORWARD_DECL(lseek, off_t, (int fd, off_t offset, int whence));
DARSHAN_FORWARD_DECL(lseek64, off64_t, (int fd, off64_t offset, int whence));
DARSHAN_FORWARD_DECL(__xstat, int, (int vers, const char* path, struct stat *buf));
DARSHAN_FORWARD_DECL(__xstat64, int, (int vers, const char* path, struct stat64 *buf));
DARSHAN_FORWARD_DECL(__lxstat, int, (int vers, const char* path, struct stat *buf));
DARSHAN_FORWARD_DECL(__lxstat64, int, (int vers, const char* path, struct stat64 *buf));
DARSHAN_FORWARD_DECL(__fxstat, int, (int vers, int fd, struct stat *buf));
DARSHAN_FORWARD_DECL(__fxstat64, int, (int vers, int fd, struct stat64 *buf));
#ifdef DARSHAN_WRAP_MMAP
DARSHAN_FORWARD_DECL(mmap, void*, (void *addr, size_t length, int prot, int flags, int fd, off_t offset));
DARSHAN_FORWARD_DECL(mmap64, void*, (void *addr, size_t length, int prot, int flags, int fd, off64_t offset));
#endif /* DARSHAN_WRAP_MMAP */
DARSHAN_FORWARD_DECL(fsync, int, (int fd));
DARSHAN_FORWARD_DECL(fdatasync, int, (int fd));
DARSHAN_FORWARD_DECL(close, int, (int fd));
DARSHAN_FORWARD_DECL(aio_read, int, (struct aiocb *aiocbp));
DARSHAN_FORWARD_DECL(aio_write, int, (struct aiocb *aiocbp));
DARSHAN_FORWARD_DECL(aio_read64, int, (struct aiocb64 *aiocbp));
DARSHAN_FORWARD_DECL(aio_write64, int, (struct aiocb64 *aiocbp));
DARSHAN_FORWARD_DECL(aio_return, ssize_t, (struct aiocb *aiocbp));
DARSHAN_FORWARD_DECL(aio_return64, ssize_t, (struct aiocb64 *aiocbp));
DARSHAN_FORWARD_DECL(lio_listio, int, (int mode, struct aiocb *const aiocb_list[], int nitems, struct sigevent *sevp));
DARSHAN_FORWARD_DECL(lio_listio64, int, (int mode, struct aiocb64 *const aiocb_list[], int nitems, struct sigevent *sevp));
DARSHAN_FORWARD_DECL(rename, int, (const char *oldpath, const char *newpath));

/* The posix_file_record_ref structure maintains necessary runtime metadata
 * for the POSIX file record (darshan_posix_file structure, defined in
 * darshan-posix-log-format.h) pointed to by 'file_rec'. This metadata
 * assists with the instrumenting of specific statistics in the file record.
 *
 * RATIONALE: the POSIX module needs to track some stateful, volatile 
 * information about each open file (like the current file offset, most recent 
 * access time, etc.) to aid in instrumentation, but this information can't be
 * stored in the darshan_posix_file struct because we don't want it to appear in
 * the final darshan log file.  We therefore associate a posix_file_record_ref
 * struct with each darshan_posix_file struct in order to track this information
 * (i.e., the mapping between posix_file_record_ref structs to darshan_posix_file
 * structs is one-to-one).
 *
 * NOTE: we use the 'darshan_record_ref' interface (in darshan-common) to
 * associate different types of handles with this posix_file_record_ref struct.
 * This allows us to index this struct (and the underlying file record) by using
 * either the corresponding Darshan record identifier (derived from the filename)
 * or by a generated file descriptor, for instance. Note that, while there should
 * only be a single Darshan record identifier that indexes a posix_file_record_ref,
 * there could be multiple open file descriptors that index it.
 */
struct posix_file_record_ref
{
    struct darshan_posix_file *file_rec;
    int64_t offset;
    int64_t last_byte_read;
    int64_t last_byte_written;
    enum darshan_io_type last_io_type;
    double last_meta_end;
    double last_read_end;
    double last_write_end;
    void *access_root;
    int access_count;
    void *stride_root;
    int stride_count;
    struct posix_aio_tracker* aio_list;
    int fs_type; /* same as darshan_fs_info->fs_type */
};

/* The posix_runtime structure maintains necessary state for storing
 * POSIX file records and for coordinating with darshan-core at 
 * shutdown time.
 */
struct posix_runtime
{
    void *rec_id_hash;
    void *fd_hash;
    int file_rec_count;
};

/* struct to track information about aio operations in flight */
struct posix_aio_tracker
{
    double tm1;
    void *aiocbp;
    struct posix_aio_tracker *next;
};

static void posix_runtime_initialize(
    void);
static struct posix_file_record_ref *posix_track_new_file_record(
    darshan_record_id rec_id, const char *path);
static void posix_aio_tracker_add(
    int fd, void *aiocbp);
static struct posix_aio_tracker* posix_aio_tracker_del(
    int fd, void *aiocbp);
static void posix_finalize_file_records(
    void *rec_ref_p);
static void posix_record_reduction_op(
    void* infile_v, void* inoutfile_v, int *len, MPI_Datatype *datatype);
static void posix_shared_record_variance(
    MPI_Comm mod_comm, struct darshan_posix_file *inrec_array,
    struct darshan_posix_file *outrec_array, int shared_rec_count);
static void posix_cleanup_runtime(
    void);

static void posix_shutdown(
    MPI_Comm mod_comm, darshan_record_id *shared_recs,
    int shared_rec_count, void **posix_buf, int *posix_buf_sz);

/* extern function def for querying record name from a STDIO stream */
extern char *darshan_stdio_lookup_record_name(FILE *stream);

static struct posix_runtime *posix_runtime = NULL;
static pthread_mutex_t posix_runtime_mutex = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
static int my_rank = -1;
static int darshan_mem_alignment = 1;

#define POSIX_LOCK() pthread_mutex_lock(&posix_runtime_mutex)
#define POSIX_UNLOCK() pthread_mutex_unlock(&posix_runtime_mutex)

#define POSIX_PRE_RECORD() do { \
    POSIX_LOCK(); \
    if(!darshan_core_disabled_instrumentation()) { \
        if(!posix_runtime) { \
            posix_runtime_initialize(); \
        } \
        if(posix_runtime) break; \
    } \
    POSIX_UNLOCK(); \
    return(ret); \
} while(0)

#define POSIX_POST_RECORD() do { \
    POSIX_UNLOCK(); \
} while(0)

#define POSIX_RECORD_OPEN(__ret, __path, __mode, __tm1, __tm2) do { \
    darshan_record_id __rec_id; \
    struct posix_file_record_ref *__rec_ref; \
    char *__newpath; \
    if(__ret < 0) break; \
    __newpath = darshan_clean_file_path(__path); \
    if(!__newpath) __newpath = (char *)__path; \
    if(darshan_core_excluded_path(__newpath)) { \
        if(__newpath != __path) free(__newpath); \
        break; \
    } \
    __rec_id = darshan_core_gen_record_id(__newpath); \
    __rec_ref = darshan_lookup_record_ref(posix_runtime->rec_id_hash, &__rec_id, sizeof(darshan_record_id)); \
    if(!__rec_ref) __rec_ref = posix_track_new_file_record(__rec_id, __newpath); \
    if(!__rec_ref) { \
        if(__newpath != __path) free(__newpath); \
        break; \
    } \
    _POSIX_RECORD_OPEN(__ret, __rec_ref, __mode, __tm1, __tm2, 1, -1); \
    darshan_instrument_fs_data(__rec_ref->fs_type, __newpath, __ret); \
    if(__newpath != __path) free(__newpath); \
} while(0)

#define POSIX_RECORD_REFOPEN(__ret, __rec_ref, __tm1, __tm2, __ref_counter) do { \
    if(__ret < 0 || !__rec_ref) break; \
    _POSIX_RECORD_OPEN(__ret, __rec_ref, 0, __tm1, __tm2, 0, __ref_counter); \
} while(0)

#define _POSIX_RECORD_OPEN(__ret, __rec_ref, __mode, __tm1, __tm2, __reset_flag, __ref_counter) do { \
    if(__mode) __rec_ref->file_rec->counters[POSIX_MODE] = __mode; \
    if(__reset_flag) { \
        __rec_ref->offset = 0; \
        __rec_ref->last_byte_written = 0; \
        __rec_ref->last_byte_read = 0; \
    } \
    __rec_ref->file_rec->counters[POSIX_OPENS] += 1; \
    if(__ref_counter >= 0) __rec_ref->file_rec->counters[__ref_counter] += 1; \
    if(__rec_ref->file_rec->fcounters[POSIX_F_OPEN_START_TIMESTAMP] == 0 || \
     __rec_ref->file_rec->fcounters[POSIX_F_OPEN_START_TIMESTAMP] > __tm1) \
        __rec_ref->file_rec->fcounters[POSIX_F_OPEN_START_TIMESTAMP] = __tm1; \
    __rec_ref->file_rec->fcounters[POSIX_F_OPEN_END_TIMESTAMP] = __tm2; \
    DARSHAN_TIMER_INC_NO_OVERLAP(__rec_ref->file_rec->fcounters[POSIX_F_META_TIME], \
        __tm1, __tm2, __rec_ref->last_meta_end); \
    darshan_add_record_ref(&(posix_runtime->fd_hash), &__ret, sizeof(int), __rec_ref); \
} while(0)

#define POSIX_RECORD_READ(__ret, __fd, __pread_flag, __pread_offset, __aligned, __tm1, __tm2) do { \
    struct posix_file_record_ref* rec_ref; \
    size_t stride; \
    int64_t this_offset; \
    int64_t file_alignment; \
    double __elapsed = __tm2-__tm1; \
    if(__ret < 0) break; \
    rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &(__fd), sizeof(int)); \
    if(!rec_ref) break; \
    if(__pread_flag) \
        this_offset = __pread_offset; \
    else \
        this_offset = rec_ref->offset; \
    /* DXT to record detailed read tracing information */ \
    dxt_posix_read(rec_ref->file_rec->base_rec.id, this_offset, __ret, __tm1, __tm2); \
    if(this_offset > rec_ref->last_byte_read) \
        rec_ref->file_rec->counters[POSIX_SEQ_READS] += 1;  \
    if(this_offset == (rec_ref->last_byte_read + 1)) \
        rec_ref->file_rec->counters[POSIX_CONSEC_READS] += 1;  \
    if(this_offset > 0 && this_offset > rec_ref->last_byte_read \
        && rec_ref->last_byte_read != 0) \
        stride = this_offset - rec_ref->last_byte_read - 1; \
    else \
        stride = 0; \
    rec_ref->last_byte_read = this_offset + __ret - 1; \
    rec_ref->offset = this_offset + __ret; \
    if(rec_ref->file_rec->counters[POSIX_MAX_BYTE_READ] < (this_offset + __ret - 1)) \
        rec_ref->file_rec->counters[POSIX_MAX_BYTE_READ] = (this_offset + __ret - 1); \
    rec_ref->file_rec->counters[POSIX_BYTES_READ] += __ret; \
    rec_ref->file_rec->counters[POSIX_READS] += 1; \
    DARSHAN_BUCKET_INC(&(rec_ref->file_rec->counters[POSIX_SIZE_READ_0_100]), __ret); \
    darshan_common_val_counter(&rec_ref->access_root, &rec_ref->access_count, __ret, \
        &(rec_ref->file_rec->counters[POSIX_ACCESS1_ACCESS]), \
        &(rec_ref->file_rec->counters[POSIX_ACCESS1_COUNT])); \
    darshan_common_val_counter(&rec_ref->stride_root, &rec_ref->stride_count, stride, \
        &(rec_ref->file_rec->counters[POSIX_STRIDE1_STRIDE]), \
        &(rec_ref->file_rec->counters[POSIX_STRIDE1_COUNT])); \
    if(!__aligned) \
        rec_ref->file_rec->counters[POSIX_MEM_NOT_ALIGNED] += 1; \
    file_alignment = rec_ref->file_rec->counters[POSIX_FILE_ALIGNMENT]; \
    if(file_alignment > 0 && (this_offset % file_alignment) != 0) \
        rec_ref->file_rec->counters[POSIX_FILE_NOT_ALIGNED] += 1; \
    if(rec_ref->last_io_type == DARSHAN_IO_WRITE) \
        rec_ref->file_rec->counters[POSIX_RW_SWITCHES] += 1; \
    rec_ref->last_io_type = DARSHAN_IO_READ; \
    if(rec_ref->file_rec->fcounters[POSIX_F_READ_START_TIMESTAMP] == 0 || \
     rec_ref->file_rec->fcounters[POSIX_F_READ_START_TIMESTAMP] > __tm1) \
        rec_ref->file_rec->fcounters[POSIX_F_READ_START_TIMESTAMP] = __tm1; \
    rec_ref->file_rec->fcounters[POSIX_F_READ_END_TIMESTAMP] = __tm2; \
    if(rec_ref->file_rec->fcounters[POSIX_F_MAX_READ_TIME] < __elapsed) { \
        rec_ref->file_rec->fcounters[POSIX_F_MAX_READ_TIME] = __elapsed; \
        rec_ref->file_rec->counters[POSIX_MAX_READ_TIME_SIZE] = __ret; } \
    DARSHAN_TIMER_INC_NO_OVERLAP(rec_ref->file_rec->fcounters[POSIX_F_READ_TIME], \
        __tm1, __tm2, rec_ref->last_read_end); \
} while(0)

#define POSIX_RECORD_WRITE(__ret, __fd, __pwrite_flag, __pwrite_offset, __aligned, __tm1, __tm2) do { \
    struct posix_file_record_ref* rec_ref; \
    size_t stride; \
    int64_t this_offset; \
    int64_t file_alignment; \
    double __elapsed = __tm2-__tm1; \
    if(__ret < 0) break; \
    rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &__fd, sizeof(int)); \
    if(!rec_ref) break; \
    if(__pwrite_flag) \
        this_offset = __pwrite_offset; \
    else \
        this_offset = rec_ref->offset; \
    /* DXT to record detailed write tracing information */ \
    dxt_posix_write(rec_ref->file_rec->base_rec.id, this_offset, __ret, __tm1, __tm2); \
    if(this_offset > rec_ref->last_byte_written) \
        rec_ref->file_rec->counters[POSIX_SEQ_WRITES] += 1; \
    if(this_offset == (rec_ref->last_byte_written + 1)) \
        rec_ref->file_rec->counters[POSIX_CONSEC_WRITES] += 1; \
    if(this_offset > 0 && this_offset > rec_ref->last_byte_written \
        && rec_ref->last_byte_written != 0) \
        stride = this_offset - rec_ref->last_byte_written - 1; \
    else \
        stride = 0; \
    rec_ref->last_byte_written = this_offset + __ret - 1; \
    rec_ref->offset = this_offset + __ret; \
    if(rec_ref->file_rec->counters[POSIX_MAX_BYTE_WRITTEN] < (this_offset + __ret - 1)) \
        rec_ref->file_rec->counters[POSIX_MAX_BYTE_WRITTEN] = (this_offset + __ret - 1); \
    rec_ref->file_rec->counters[POSIX_BYTES_WRITTEN] += __ret; \
    rec_ref->file_rec->counters[POSIX_WRITES] += 1; \
    DARSHAN_BUCKET_INC(&(rec_ref->file_rec->counters[POSIX_SIZE_WRITE_0_100]), __ret); \
    darshan_common_val_counter(&rec_ref->access_root, &rec_ref->access_count, __ret, \
        &(rec_ref->file_rec->counters[POSIX_ACCESS1_ACCESS]), \
        &(rec_ref->file_rec->counters[POSIX_ACCESS1_COUNT])); \
    darshan_common_val_counter(&rec_ref->stride_root, &rec_ref->stride_count, stride, \
        &(rec_ref->file_rec->counters[POSIX_STRIDE1_STRIDE]), \
        &(rec_ref->file_rec->counters[POSIX_STRIDE1_COUNT])); \
    if(!__aligned) \
        rec_ref->file_rec->counters[POSIX_MEM_NOT_ALIGNED] += 1; \
    file_alignment = rec_ref->file_rec->counters[POSIX_FILE_ALIGNMENT]; \
    if(file_alignment > 0 && (this_offset % file_alignment) != 0) \
        rec_ref->file_rec->counters[POSIX_FILE_NOT_ALIGNED] += 1; \
    if(rec_ref->last_io_type == DARSHAN_IO_READ) \
        rec_ref->file_rec->counters[POSIX_RW_SWITCHES] += 1; \
    rec_ref->last_io_type = DARSHAN_IO_WRITE; \
    if(rec_ref->file_rec->fcounters[POSIX_F_WRITE_START_TIMESTAMP] == 0 || \
     rec_ref->file_rec->fcounters[POSIX_F_WRITE_START_TIMESTAMP] > __tm1) \
        rec_ref->file_rec->fcounters[POSIX_F_WRITE_START_TIMESTAMP] = __tm1; \
    rec_ref->file_rec->fcounters[POSIX_F_WRITE_END_TIMESTAMP] = __tm2; \
    if(rec_ref->file_rec->fcounters[POSIX_F_MAX_WRITE_TIME] < __elapsed) { \
        rec_ref->file_rec->fcounters[POSIX_F_MAX_WRITE_TIME] = __elapsed; \
        rec_ref->file_rec->counters[POSIX_MAX_WRITE_TIME_SIZE] = __ret; } \
    DARSHAN_TIMER_INC_NO_OVERLAP(rec_ref->file_rec->fcounters[POSIX_F_WRITE_TIME], \
        __tm1, __tm2, rec_ref->last_write_end); \
} while(0)

#define POSIX_LOOKUP_RECORD_STAT(__path, __statbuf, __tm1, __tm2) do { \
    darshan_record_id rec_id; \
    struct posix_file_record_ref* rec_ref; \
    char *newpath = darshan_clean_file_path(__path); \
    if(!newpath) newpath = (char *)__path; \
    if(darshan_core_excluded_path(newpath)) { \
        if(newpath != __path) free(newpath); \
        break; \
    } \
    rec_id = darshan_core_gen_record_id(newpath); \
    rec_ref = darshan_lookup_record_ref(posix_runtime->rec_id_hash, &rec_id, sizeof(darshan_record_id)); \
    if(!rec_ref) rec_ref = posix_track_new_file_record(rec_id, newpath); \
    if(newpath != __path) free(newpath); \
    if(rec_ref) { \
        POSIX_RECORD_STAT(rec_ref, __statbuf, __tm1, __tm2); \
    } \
} while(0)

#define POSIX_RECORD_STAT(__rec_ref, __statbuf, __tm1, __tm2) do { \
    (__rec_ref)->file_rec->counters[POSIX_STATS] += 1; \
    DARSHAN_TIMER_INC_NO_OVERLAP((__rec_ref)->file_rec->fcounters[POSIX_F_META_TIME], \
        __tm1, __tm2, (__rec_ref)->last_meta_end); \
} while(0)


/**********************************************************
 *      Wrappers for POSIX I/O functions of interest      * 
 **********************************************************/

int DARSHAN_DECL(open)(const char *path, int flags, ...)
{
    int mode = 0;
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(open);

    if(flags & O_CREAT) 
    {
        va_list arg;
        va_start(arg, flags);
        mode = va_arg(arg, int);
        va_end(arg);

        tm1 = darshan_core_wtime();
        ret = __real_open(path, flags, mode);
        tm2 = darshan_core_wtime();
    }
    else
    {
        tm1 = darshan_core_wtime();
        ret = __real_open(path, flags);
        tm2 = darshan_core_wtime();
    }

    POSIX_PRE_RECORD();
    POSIX_RECORD_OPEN(ret, path, mode, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(__open_2)(const char *path, int oflag)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(__open_2);

    tm1 = darshan_core_wtime();
    ret = __real___open_2(path, oflag);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_OPEN(ret, path, 0, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(open64)(const char *path, int flags, ...)
{
    int mode = 0;
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(open64);

    if(flags & O_CREAT)
    {
        va_list arg;
        va_start(arg, flags);
        mode = va_arg(arg, int);
        va_end(arg);

        tm1 = darshan_core_wtime();
        ret = __real_open64(path, flags, mode);
        tm2 = darshan_core_wtime();
    }
    else
    {
        tm1 = darshan_core_wtime();
        ret = __real_open64(path, flags);
        tm2 = darshan_core_wtime();
    }

    POSIX_PRE_RECORD();
    POSIX_RECORD_OPEN(ret, path, mode, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(creat)(const char* path, mode_t mode)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(creat);

    tm1 = darshan_core_wtime();
    ret = __real_creat(path, mode);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_OPEN(ret, path, mode, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(creat64)(const char* path, mode_t mode)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(creat64);

    tm1 = darshan_core_wtime();
    ret = __real_creat64(path, mode);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_OPEN(ret, path, mode, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(dup)(int oldfd)
{
    int ret;
    struct posix_file_record_ref *rec_ref;
    double tm1, tm2;

    MAP_OR_FAIL(dup);

    tm1 = darshan_core_wtime();
    ret = __real_dup(oldfd);
    tm2 = darshan_core_wtime();

    if(ret >= 0)
    {
        POSIX_PRE_RECORD();
        rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash,
            &oldfd, sizeof(oldfd));
        POSIX_RECORD_REFOPEN(ret, rec_ref, tm1, tm2, POSIX_DUPS);
        POSIX_POST_RECORD();
    }

    return(ret);
}

int DARSHAN_DECL(dup2)(int oldfd, int newfd)
{
    int ret;
    struct posix_file_record_ref *rec_ref;
    double tm1, tm2;

    MAP_OR_FAIL(dup2);

    tm1 = darshan_core_wtime();
    ret = __real_dup2(oldfd, newfd);
    tm2 = darshan_core_wtime();

    if(ret >=0)
    {
        POSIX_PRE_RECORD();
        rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash,
            &oldfd, sizeof(oldfd));
        POSIX_RECORD_REFOPEN(ret, rec_ref, tm1, tm2, POSIX_DUPS);
        POSIX_POST_RECORD();
    }

    return(ret);
}

int DARSHAN_DECL(dup3)(int oldfd, int newfd, int flags)
{
    int ret;
    struct posix_file_record_ref *rec_ref;
    double tm1, tm2;

    MAP_OR_FAIL(dup3);

    tm1 = darshan_core_wtime();
    ret = __real_dup3(oldfd, newfd, flags);
    tm2 = darshan_core_wtime();

    if(ret >=0)
    {
        POSIX_PRE_RECORD();
        rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash,
            &oldfd, sizeof(oldfd));
        POSIX_RECORD_REFOPEN(ret, rec_ref, tm1, tm2, POSIX_DUPS);
        POSIX_POST_RECORD();
    }

    return(ret);
}

int DARSHAN_DECL(fileno)(FILE *stream)
{
    int ret;
    double tm1, tm2;
    darshan_record_id rec_id;
    struct posix_file_record_ref *rec_ref;

    MAP_OR_FAIL(fileno);

    tm1 = darshan_core_wtime();
    ret = __real_fileno(stream);
    tm2 = darshan_core_wtime();

    if(ret >= 0)
    {
        char *rec_name = darshan_stdio_lookup_record_name(stream);
        if(rec_name)
        {
            rec_id = darshan_core_gen_record_id(rec_name);

            POSIX_PRE_RECORD();
            rec_ref = darshan_lookup_record_ref(posix_runtime->rec_id_hash,
                &rec_id, sizeof(darshan_record_id));
            if(!rec_ref)
                rec_ref = posix_track_new_file_record(rec_id, rec_name);
            POSIX_RECORD_REFOPEN(ret, rec_ref, tm1, tm2, POSIX_FILENOS);
            POSIX_POST_RECORD();
        }
    }

    return(ret);
}

int DARSHAN_DECL(mkstemp)(char* template)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(mkstemp);

    tm1 = darshan_core_wtime();
    ret = __real_mkstemp(template);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_OPEN(ret, template, 0, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(mkostemp)(char* template, int flags)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(mkostemp);

    tm1 = darshan_core_wtime();
    ret = __real_mkostemp(template, flags);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_OPEN(ret, template, 0, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(mkstemps)(char* template, int suffixlen)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(mkstemps);

    tm1 = darshan_core_wtime();
    ret = __real_mkstemps(template, suffixlen);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_OPEN(ret, template, 0, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(mkostemps)(char* template, int suffixlen, int flags)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(mkostemps);

    tm1 = darshan_core_wtime();
    ret = __real_mkostemps(template, suffixlen, flags);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_OPEN(ret, template, 0, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

ssize_t DARSHAN_DECL(read)(int fd, void *buf, size_t count)
{
    ssize_t ret;
    int aligned_flag = 0;
    double tm1, tm2;

    MAP_OR_FAIL(read);

    if((unsigned long)buf % darshan_mem_alignment == 0) aligned_flag = 1;

    tm1 = darshan_core_wtime();
    ret = __real_read(fd, buf, count);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_READ(ret, fd, 0, 0, aligned_flag, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

ssize_t DARSHAN_DECL(write)(int fd, const void *buf, size_t count)
{
    ssize_t ret;
    int aligned_flag = 0;
    double tm1, tm2;

    MAP_OR_FAIL(write);

    if((unsigned long)buf % darshan_mem_alignment == 0) aligned_flag = 1;

    tm1 = darshan_core_wtime();
    ret = __real_write(fd, buf, count);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_WRITE(ret, fd, 0, 0, aligned_flag, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

ssize_t DARSHAN_DECL(pread)(int fd, void *buf, size_t count, off_t offset)
{
    ssize_t ret;
    int aligned_flag = 0;
    double tm1, tm2;

    MAP_OR_FAIL(pread);

    if((unsigned long)buf % darshan_mem_alignment == 0) aligned_flag = 1;

    tm1 = darshan_core_wtime();
    ret = __real_pread(fd, buf, count, offset);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_READ(ret, fd, 1, offset, aligned_flag, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

ssize_t DARSHAN_DECL(pwrite)(int fd, const void *buf, size_t count, off_t offset)
{
    ssize_t ret;
    int aligned_flag = 0;
    double tm1, tm2;

    MAP_OR_FAIL(pwrite);

    if((unsigned long)buf % darshan_mem_alignment == 0) aligned_flag = 1;

    tm1 = darshan_core_wtime();
    ret = __real_pwrite(fd, buf, count, offset);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_WRITE(ret, fd, 1, offset, aligned_flag, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

ssize_t DARSHAN_DECL(pread64)(int fd, void *buf, size_t count, off64_t offset)
{
    ssize_t ret;
    int aligned_flag = 0;
    double tm1, tm2;

    MAP_OR_FAIL(pread64);

    if((unsigned long)buf % darshan_mem_alignment == 0) aligned_flag = 1;

    tm1 = darshan_core_wtime();
    ret = __real_pread64(fd, buf, count, offset);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_READ(ret, fd, 1, offset, aligned_flag, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

ssize_t DARSHAN_DECL(pwrite64)(int fd, const void *buf, size_t count, off64_t offset)
{
    ssize_t ret;
    int aligned_flag = 0;
    double tm1, tm2;

    MAP_OR_FAIL(pwrite64);

    if((unsigned long)buf % darshan_mem_alignment == 0) aligned_flag = 1;

    tm1 = darshan_core_wtime();
    ret = __real_pwrite64(fd, buf, count, offset);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_WRITE(ret, fd, 1, offset, aligned_flag, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

ssize_t DARSHAN_DECL(readv)(int fd, const struct iovec *iov, int iovcnt)
{
    ssize_t ret;
    int aligned_flag = 1;
    int i;
    double tm1, tm2;

    MAP_OR_FAIL(readv);

    for(i=0; i<iovcnt; i++)
    {
        if(((unsigned long)iov[i].iov_base % darshan_mem_alignment) != 0)
            aligned_flag = 0;
    }

    tm1 = darshan_core_wtime();
    ret = __real_readv(fd, iov, iovcnt);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_READ(ret, fd, 0, 0, aligned_flag, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

ssize_t DARSHAN_DECL(writev)(int fd, const struct iovec *iov, int iovcnt)
{
    ssize_t ret;
    int aligned_flag = 1;
    int i;
    double tm1, tm2;

    MAP_OR_FAIL(writev);

    for(i=0; i<iovcnt; i++)
    {
        if(((unsigned long)iov[i].iov_base % darshan_mem_alignment) != 0)
            aligned_flag = 0;
    }

    tm1 = darshan_core_wtime();
    ret = __real_writev(fd, iov, iovcnt);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    POSIX_RECORD_WRITE(ret, fd, 0, 0, aligned_flag, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

off_t DARSHAN_DECL(lseek)(int fd, off_t offset, int whence)
{
    off_t ret;
    struct posix_file_record_ref *rec_ref;
    double tm1, tm2;

    MAP_OR_FAIL(lseek);

    tm1 = darshan_core_wtime();
    ret = __real_lseek(fd, offset, whence);
    tm2 = darshan_core_wtime();

    if(ret >= 0)
    {
        POSIX_PRE_RECORD();
        rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &fd, sizeof(int));
        if(rec_ref)
        {
            rec_ref->offset = ret;
            DARSHAN_TIMER_INC_NO_OVERLAP(
                rec_ref->file_rec->fcounters[POSIX_F_META_TIME],
                tm1, tm2, rec_ref->last_meta_end);
            rec_ref->file_rec->counters[POSIX_SEEKS] += 1;
        }
        POSIX_POST_RECORD();
    }

    return(ret);
}

off64_t DARSHAN_DECL(lseek64)(int fd, off64_t offset, int whence)
{
    off_t ret;
    struct posix_file_record_ref *rec_ref;
    double tm1, tm2;

    MAP_OR_FAIL(lseek64);

    tm1 = darshan_core_wtime();
    ret = __real_lseek64(fd, offset, whence);
    tm2 = darshan_core_wtime();

    if(ret >= 0)
    {
        POSIX_PRE_RECORD();
        rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &fd, sizeof(int));
        if(rec_ref)
        {
            rec_ref->offset = ret;
            DARSHAN_TIMER_INC_NO_OVERLAP(
                rec_ref->file_rec->fcounters[POSIX_F_META_TIME],
                tm1, tm2, rec_ref->last_meta_end);
            rec_ref->file_rec->counters[POSIX_SEEKS] += 1;
        }
        POSIX_POST_RECORD();
    }

    return(ret);
}

int DARSHAN_DECL(__xstat)(int vers, const char *path, struct stat *buf)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(__xstat);

    tm1 = darshan_core_wtime();
    ret = __real___xstat(vers, path, buf);
    tm2 = darshan_core_wtime();

    if(ret < 0 || !S_ISREG(buf->st_mode))
        return(ret);

    POSIX_PRE_RECORD();
    POSIX_LOOKUP_RECORD_STAT(path, buf, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(__xstat64)(int vers, const char *path, struct stat64 *buf)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(__xstat64);

    tm1 = darshan_core_wtime();
    ret = __real___xstat64(vers, path, buf);
    tm2 = darshan_core_wtime();

    if(ret < 0 || !S_ISREG(buf->st_mode))
        return(ret);

    POSIX_PRE_RECORD();
    POSIX_LOOKUP_RECORD_STAT(path, buf, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(__lxstat)(int vers, const char *path, struct stat *buf)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(__lxstat);

    tm1 = darshan_core_wtime();
    ret = __real___lxstat(vers, path, buf);
    tm2 = darshan_core_wtime();

    if(ret < 0 || !S_ISREG(buf->st_mode))
        return(ret);

    POSIX_PRE_RECORD();
    POSIX_LOOKUP_RECORD_STAT(path, buf, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(__lxstat64)(int vers, const char *path, struct stat64 *buf)
{
    int ret;
    double tm1, tm2;

    MAP_OR_FAIL(__lxstat64);

    tm1 = darshan_core_wtime();
    ret = __real___lxstat64(vers, path, buf);
    tm2 = darshan_core_wtime();

    if(ret < 0 || !S_ISREG(buf->st_mode))
        return(ret);

    POSIX_PRE_RECORD();
    POSIX_LOOKUP_RECORD_STAT(path, buf, tm1, tm2);
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(__fxstat)(int vers, int fd, struct stat *buf)
{
    int ret;
    struct posix_file_record_ref *rec_ref;
    double tm1, tm2;

    MAP_OR_FAIL(__fxstat);

    tm1 = darshan_core_wtime();
    ret = __real___fxstat(vers, fd, buf);
    tm2 = darshan_core_wtime();

    if(ret < 0 || !S_ISREG(buf->st_mode))
        return(ret);

    POSIX_PRE_RECORD();
    rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &fd, sizeof(int));
    if(rec_ref)
    {
        POSIX_RECORD_STAT(rec_ref, buf, tm1, tm2);
    }
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(__fxstat64)(int vers, int fd, struct stat64 *buf)
{
    int ret;
    struct posix_file_record_ref *rec_ref;
    double tm1, tm2;

    MAP_OR_FAIL(__fxstat64);

    tm1 = darshan_core_wtime();
    ret = __real___fxstat64(vers, fd, buf);
    tm2 = darshan_core_wtime();

    if(ret < 0 || !S_ISREG(buf->st_mode))
        return(ret);

    POSIX_PRE_RECORD();
    rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &fd, sizeof(int));
    if(rec_ref)
    {
        POSIX_RECORD_STAT(rec_ref, buf, tm1, tm2);
    }
    POSIX_POST_RECORD();

    return(ret);
}

#ifdef DARSHAN_WRAP_MMAP
void* DARSHAN_DECL(mmap)(void *addr, size_t length, int prot, int flags,
    int fd, off_t offset)
{
    void* ret;
    struct posix_file_record_ref *rec_ref;

    MAP_OR_FAIL(mmap);

    if(fd < 0 || (flags & MAP_ANONYMOUS))
    {
        /* mmap is not associated with a backing file; skip all Darshan
         * characterization attempts.
         */
        return(__real_mmap(addr, length, prot, flags, fd, offset));
    }

    ret = __real_mmap(addr, length, prot, flags, fd, offset);
    if(ret == MAP_FAILED)
        return(ret);

    POSIX_PRE_RECORD();
    rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &fd, sizeof(int));
    if(rec_ref)
    {
        rec_ref->file_rec->counters[POSIX_MMAPS] += 1;
    }
    POSIX_POST_RECORD();

    return(ret);
}
#endif /* DARSHAN_WRAP_MMAP */

#ifdef DARSHAN_WRAP_MMAP
void* DARSHAN_DECL(mmap64)(void *addr, size_t length, int prot, int flags,
    int fd, off64_t offset)
{
    void* ret;
    struct posix_file_record_ref *rec_ref;

    MAP_OR_FAIL(mmap64);

    if(fd < 0 || (flags & MAP_ANONYMOUS))
    {
        /* mmap is not associated with a backing file; skip all Darshan
         * characterization attempts.
         */
        return(__real_mmap64(addr, length, prot, flags, fd, offset));
    }

    ret = __real_mmap64(addr, length, prot, flags, fd, offset);
    if(ret == MAP_FAILED)
        return(ret);

    POSIX_PRE_RECORD();
    rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &fd, sizeof(int));
    if(rec_ref)
    {
        rec_ref->file_rec->counters[POSIX_MMAPS] += 1;
    }
    POSIX_POST_RECORD();

    return(ret);
}
#endif /* DARSHAN_WRAP_MMAP */

int DARSHAN_DECL(fsync)(int fd)
{
    int ret;
    struct posix_file_record_ref *rec_ref;
    double tm1, tm2;

    MAP_OR_FAIL(fsync);

    tm1 = darshan_core_wtime();
    ret = __real_fsync(fd);
    tm2 = darshan_core_wtime();

    if(ret < 0)
        return(ret);

    POSIX_PRE_RECORD();
    rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &fd, sizeof(int));
    if(rec_ref)
    {
        DARSHAN_TIMER_INC_NO_OVERLAP(
            rec_ref->file_rec->fcounters[POSIX_F_WRITE_TIME],
            tm1, tm2, rec_ref->last_write_end);
        rec_ref->file_rec->counters[POSIX_FSYNCS] += 1;
    }
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(fdatasync)(int fd)
{
    int ret;
    struct posix_file_record_ref *rec_ref;
    double tm1, tm2;

    MAP_OR_FAIL(fdatasync);

    tm1 = darshan_core_wtime();
    ret = __real_fdatasync(fd);
    tm2 = darshan_core_wtime();

    if(ret < 0)
        return(ret);

    POSIX_PRE_RECORD();
    rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &fd, sizeof(int));
    if(rec_ref)
    {
        DARSHAN_TIMER_INC_NO_OVERLAP(
            rec_ref->file_rec->fcounters[POSIX_F_WRITE_TIME],
            tm1, tm2, rec_ref->last_write_end);
        rec_ref->file_rec->counters[POSIX_FDSYNCS] += 1;
    }
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(close)(int fd)
{
    int ret;
    struct posix_file_record_ref *rec_ref;
    double tm1, tm2;

    MAP_OR_FAIL(close);

    tm1 = darshan_core_wtime();
    ret = __real_close(fd);
    tm2 = darshan_core_wtime();

    POSIX_PRE_RECORD();
    rec_ref = darshan_lookup_record_ref(posix_runtime->fd_hash, &fd, sizeof(int));
    if(rec_ref)
    {
        rec_ref->last_byte_written = 0;
        rec_ref->last_byte_read = 0;
        if(rec_ref->file_rec->fcounters[POSIX_F_CLOSE_START_TIMESTAMP] == 0 ||
         rec_ref->file_rec->fcounters[POSIX_F_CLOSE_START_TIMESTAMP] > tm1)
           rec_ref->file_rec->fcounters[POSIX_F_CLOSE_START_TIMESTAMP] = tm1;
        rec_ref->file_rec->fcounters[POSIX_F_CLOSE_END_TIMESTAMP] = tm2;
        DARSHAN_TIMER_INC_NO_OVERLAP(
            rec_ref->file_rec->fcounters[POSIX_F_META_TIME],
            tm1, tm2, rec_ref->last_meta_end);
        darshan_delete_record_ref(&(posix_runtime->fd_hash), &fd, sizeof(int));
    }
    POSIX_POST_RECORD();

    return(ret);
}

int DARSHAN_DECL(aio_read)(struct aiocb *aiocbp)
{
    int ret;

    MAP_OR_FAIL(aio_read);

    ret = __real_aio_read(aiocbp);
    if(ret == 0)
    {
        POSIX_PRE_RECORD();
        posix_aio_tracker_add(aiocbp->aio_fildes, aiocbp);
        POSIX_POST_RECORD();
    }

    return(ret);
}

int DARSHAN_DECL(aio_write)(struct aiocb *aiocbp)