//  File: tools.c --------------------------------------------------------------
//  The tools library.
//  Assorted utility routines for use in C programs.
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
#include "tools.h"
// -----------------------------------------------------------------------------
//  Routine screen and process management. 									  --
// -----------------------------------------------------------------------------
void
clearscreen( void ) {   fprintf( stderr, "\f" );  }
// -----------------------------------------------------------------------------
// Print termination message.
void
bye( void ) { fputs( "\nNormal termination.\n", stderr ); }

// -----------------------------------------------------------------------------
// Print a neat header on the output.
void
banner( void ){ fbanner( stdout ); }

// -----------------------------------------------------------------------------
void
fbanner( stream sout )
{   char date[16], time[9];

    when(date, time);
    clearscreen();
    fprintf(sout,"\n-------------------------------------------------------\n");
    fprintf(sout,"\t%s \n\t%s \n\t%s  %s\n", NAME, CLASS, date, time );
    fprintf(sout,"-------------------------------------------------------\n");
}

// -----------------------------------------------------------------------------
//  This is a handy function for messages of all sorts.
//  It formats and prints to stderr.
//  It accepts a format followed by a variable number of data items to print.
void
say (string format, ...)
{   va_list vargs;                               // optional arguments

    va_start( vargs, format );
    vfprintf( stderr, format, vargs );
    fprintf( stderr, "\n" );
}

// -----------------------------------------------------------------------------
// Intended for use after a non-fatal error in a system call.
// In addition to the work done by say(), it prints the system error comment.
void
sayp (string format, ...)
{   int err = errno;						// capture the global error code.
	va_list vargs;                          // optional arguments

    va_start( vargs, format );
	vfprintf( stderr, format, vargs );
    fprintf( stderr, "\n         %s\n", strerror( err ));
}

// -----------------------------------------------------------------------------
// Delay progress of program for some number of seconds using a "busy wait".
void
delay( int seconds )
{   time_t goal;

    goal = time( NULL ) + seconds;
    do  { /* Nothing */ } while (time(NULL) < goal);
}

// -----------------------------------------------------------------------------
// Print message and wait for the user to type a newline.
void
hold( void )
{
    fputs( "\n\n\aPress '.' and 'Enter' to continue", stderr );
    while ( getchar() != '.' );  				// tight loop ;
}

// -----------------------------------------------------------------------------
// Error handling and error recovery functions.
//-------------------------------------------------------------------------------

// -----------------------------------------------------------------------------
// This function is for error messages.
//    It takes a format argument followed by any number of data arguments.
//    It formats and prints an error message, then exits properly.
int
fatal (string format, ...)
{   va_list vargs;                               // optional arguments

    va_start(vargs, format);
    vfprintf(stderr, format, vargs);
    fprintf(stderr, "\a\a\n");
    exit(1);
}
// -----------------------------------------------------------------------------
// This function is for error messages following system calls.
// In addition to the work done by fatal(), it prints the system error comment.
int
fatalp (string format, ...)
{   int err = errno;						// capture the global error code.
	va_list vargs;                          // optional arguments

    va_start(vargs, format);
	vfprintf(stderr, format, vargs);
    fprintf( stderr, "\n        Error code %i: %s\n", err, strerror( err ));
    exit(1);
}

// -----------------------------------------------------------------------------
// Clean out the rest of the current line, discarding all characters up to and
//    including the newline character. Use after an input error to prepare for
//    resumption of numeric input.
void
cleanline ( stream sin )
{   char ch;                      // Character currently under input scanner.

    do {
		ch = fgetc(sin);           			// Read next character
	} while ( !feof( sin ) && ch != '\n' );	// Quit at first newline
}

// -----------------------------------------------------------------------------
// Clean out the rest of the current line up to and including the newline
//    character. Write the characters to an error log file.  Use after an
//    input error to prepare for resumption of numeric input.
void
clean_and_log( stream sin, stream sout )
{   char ch;                      // Character currently under input scanner.

    do {
		ch = fgetc(sin);           			// Read next character
		fputc(ch, sout); 					// Echo to error stream
	} while ( !feof( sin ) && ch != '\n' );	// Quit at first newline
}

// -----------------------------------------------------------------------------
//  Routines for handling the time and date.
// -----------------------------------------------------------------------------

// -----------------------------------------------------------------------------
// Store the current date and time in the arguments.
//      System's date format is: "Fri Jun  9 10:15:55 1995\n"
//      After extraction, date is: "Fri Jun  9 1995"    hour is: "10:15:55"
void
when( char date[], char hour[] )
{
    time_t now;          // Stores an integer encoding of the date and time.
    string nowstring;    // Stores the date and time in a readable form.

    now = time(NULL);              // Get the date and time from the system.
    nowstring = ctime(&now);                   // Convert to string form.
    strncpy( date, nowstring, 10);             // Extract day, month, date.
    strncpy( &date[10], &nowstring[19], 5);    // Extract space and year.
    date[15]  = '\0';                          // Add the string terminator.
    strncpy( hour, &nowstring[11], 8);         // Copy hour:minutes:seconds.
    hour[8]  = '\0';                           // Add the string terminator.
}

// -----------------------------------------------------------------------------
// Store the current date in the argument and return a pointer to it.
//      date format is: "Fri Jun  9 1995"
string
today( char date[] )
{
    time_t now;          // Stores an integer encoding of the date and time.
    string nowstring;    // Stores the date and time in a readable form.

    now = time(NULL);              // Get the date and time from the system.
    nowstring = ctime(&now);                   // Convert to string form.
    strncpy( date, nowstring, 10);             // Extract day, month, date.
    strncpy( &date[10], &nowstring[19], 5);    // Extract space and year.
    date[15]  = '\0';                          // Add the string terminator.
    return( date );
}

// -----------------------------------------------------------------------------
// Store the current time in hour and return a pointer to it.
//      hour format is: "10:15:55"
string
oclock( char hour[] )
{
    time_t now;          // Stores an integer encoding of the date and time.
    string nowstring;    // Stores the date and time in a readable form.

    now = time(NULL);              // Get the date and time from the system.
    nowstring = ctime(&now);              // Convert to string form.
    strncpy( hour, &nowstring[11], 8);    // Extract hour, minutes, seconds.
    hour[8]  = '\0';                      // Add the string terminator.
    return( hour );
}