#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
/*
 * 'slurp' reads the file identified by 'path' into a character buffer
 * pointed at by 'buf', optionally adding a terminating NUL if
 * 'add_nul' is true. On success, the size of the file is returned; on
 * failure, -1 is returned and ERRNO is set by the underlying system
 * or library call that failed.
 *
 * WARNING: 'slurp' malloc()s memory to '*buf' which must be freed by
 * the caller.
 */
long wslurp(const wchar_t* path, char **buf, bool add_nul)
{
    FILE  *fp;
    size_t fsz;
    long   off_end;
    int    rc;

    /* Open the file */
    fp = _wfopen(path, L"rb");
    if( NULL == fp ) {
        return -1L;
    }

    /* Seek to the end of the file */
    rc = fseek(fp, 0L, SEEK_END);
    if( 0 != rc ) {
        return -1L;
    }

    /* Byte offset to the end of the file (size) */
    if( 0 > (off_end = ftell(fp)) ) {
        return -1L;
    }
    fsz = (size_t)off_end;

    /* Allocate a buffer to hold the whole file */
    *buf = malloc( fsz+(int)add_nul );
    if( NULL == *buf ) {
        return -1L;
    }

    /* Rewind file pointer to start of file */
    rewind(fp);

    /* Slurp file into buffer */
    if( fsz != fread(*buf, 1, fsz, fp) ) {
        free(*buf);
        return -1L;
    }

    /* Close the file */
    if( EOF == fclose(fp) ) {
        free(*buf);
        return -1L;
    }

    if( add_nul ) {
        /* Make sure the buffer is NUL-terminated, just in case */
        buf[fsz] = '\0';
    }

    /* Return the file size */
    return (long)fsz;
}