-/* Suspend/resume I/O routines (SAVWDS, SAVARR, SAVWRD) */
-
-void fSAVWDS(long *W1, long *W2, long *W3, long *W4,
- long *W5, long *W6, long *W7)
-/* Write or read 7 variables. See SAVWRD. */
-{
- SAVWRD(0,(*W1));
- SAVWRD(0,(*W2));
- SAVWRD(0,(*W3));
- SAVWRD(0,(*W4));
- SAVWRD(0,(*W5));
- SAVWRD(0,(*W6));
- SAVWRD(0,(*W7));
-}
-
-void fSAVARR(long arr[], long n)
-/* Write or read an array of n words. See SAVWRD. */
-{
- long i;
-
- for (i=1; i<=n; i++) {
- SAVWRD(0,arr[i]);
- }
- return;
-}
-
-void fSAVWRD(long op, long *pword)
-/* If OP<0, start writing a file, using word to initialise encryption; save
- * word in the file. If OP>0, start reading a file; read the file to find
- * the value with which to decrypt the rest. In either case, if a file is
- * already open, finish writing/reading it and don't start a new one. If OP=0,
- * read/write a single word. Words are buffered in case that makes for more
- * efficient disk use. We also compute a simple checksum to catch elementary
- * poking within the saved file. When we finish reading/writing the file,
- * we store zero into *PWORD if there's no checksum error, else nonzero. */
-{
- static long buf[250], cksum = 0, h1, hash = 0, n = 0, state = 0;
-
- if (op != 0)
- {
- long ifvar = state;
- switch (ifvar<0 ? -1 : (ifvar>0 ? 1 : 0))
- {
- case -1:
- case 1:
- if (n == 250)SAVEIO(1,state > 0,buf);
- n=MOD(n,250)+1;
- if (state <= 0) {
- n--; buf[n]=cksum; n++;
- SAVEIO(1,false,buf);
- }
- n--; *pword=buf[n]-cksum; n++;
- SAVEIO(-1,state > 0,buf);
- state=0;
- break;
- case 0: /* FIXME: Huh? should be impossible */
- state=op;
- SAVEIO(0,state > 0,buf);
- n=1;
- if (state <= 0) {
- hash=MOD(*pword,1048576L);
- buf[0]=1234L*5678L-hash;
- }
- SAVEIO(1,true,buf);
- hash=MOD(1234L*5678L-buf[0],1048576L);
- cksum=buf[0];
- return;
- }
- }
- if (state == 0)
- return;
- if (n == 250)
- SAVEIO(1,state > 0,buf);
- n=MOD(n,250)+1;
- h1=MOD(hash*1093L+221573L,1048576L);
- hash=MOD(h1*1093L+221573L,1048576L);
- h1=MOD(h1,1234)*765432+MOD(hash,123);
- n--;
- if (state > 0)
- *pword=buf[n]+h1;
- buf[n]=*pword-h1;
- n++;
- cksum=MOD(cksum*13+*pword,1000000000L);
-}
-