source: trunk/minix/commands/advent/database.c@ 15

/*      program DATABASE.C                                      */

#include        <string.h>
#include        <stdio.h>
#include        "advent.h"
#include        "advdec.h"
#include        "advtext.h"

static char oline[256];

_PROTOTYPE(void rdupto, (FILE *, int, int, char *));
_PROTOTYPE(void rdskip, (FILE *, int, int));

/*
  Function to scan a file up to a specified
  point and either print or return a string.
*/
void rdupto(fdi, uptoc, print, string)
FILE *fdi;
int uptoc, print;
char *string;
{
    int c, i;
    static _CONST unsigned char key[4] = {'c' | 0x80, 'L' | 0x80,
                                          'y' | 0x80, 'D' | 0x80};

    i = 1;
    while ((c = getc(fdi)) != uptoc && c != EOF) {
        if (c == '\n')
            i = 1;
        if (c >= 0x80)
            c ^= key[i++ & 3];
        if (c == '\r')
            continue;
        if (print)
            putchar(c);
        else
            *string++ = (char) c;
    }
    if (!print)
        *string = '\0';
    return;
}

/*
  Function to read a file skipping
  a given character a specified number
  of times, with or without repositioning
  the file.
*/
void rdskip(fdi, skipc, n)
FILE *fdi;
int skipc, n;
{
    int c;

    while (n--)
        while ((c = getc(fdi)) != skipc)
            if (c == EOF)
                bug(32);
    return;
}

/*
  Routine to request a yes or no answer to a question.
*/
boolean yes(msg1, msg2, msg3)
int msg1, msg2, msg3;
{
    char answer[INPUTBUFLEN];

    if (msg1)
        rspeak(msg1);
    do {
        switch (*ask("\n> ", answer, sizeof(answer))) {
        case 'n':
        case 'N':
            if (msg3)
                rspeak(msg3);
            return (FALSE);
        case 'y':
        case 'Y':
            if (msg2)
                rspeak(msg2);
            return (TRUE);
        default:
            fputs("Please answer Y (yes) or N (no).", stdout);
        }
    } while (TRUE);
}

/*
  Print a location description from "advent4.txt"
*/
void rspeak(msg)
int msg;
{
    if (msg == 54)
        printf("ok.\n");
    else {
        fseek(fd4, idx4[msg - 1], 0);
        rdupto(fd4, '#', 1, 0);
    }
    return;
}

/*
  Print an item message for a given state from "advent3.txt"
*/
void pspeak(item, state)
int item, state;
{
    fseek(fd3, idx3[item - 1], 0);
    rdskip(fd3, '/', state + 2);
    rdupto(fd3, '/', FALSE, oline);
    if (strncmp(oline, "<$$<", 4) != 0)
        printf("%s", oline);
    return;
}

/*
  Print a long location description from "advent1.txt"
*/
void desclg(loc)
int loc;
{
    fseek(fd1, idx1[loc - 1], 0);
    rdupto(fd1, '#', 1, 0);
    return;
}

/*
  Print a short location description from "advent2.txt"
*/
void descsh(loc)
int loc;
{
    fseek(fd2, idx2[loc - 1], 0);
    rdupto(fd2, '#', 1, 0);
    return;
}