void doMacroCall(int macroaddress) {
char op = sym; // save sym for restore
if (macroaddress >= 0) {
char *fetchmark = fetchptr; // save the current parse pointer
// call the macro
calleeprommacro(findend(macroaddress)); // register the macro into the parser stream
getsym();
getstatementlist(); // parse and execute the macro code here
if (sym != s_eof) expected(M_eof);
// restore parsing context so we can resume cleanly
fetchptr = fetchmark; // restore pointer
primec(); // and inchar
sym = op; // restore saved sym
}
}
// call a macro and push its return value on the stack
//
void domacrocall(int macroaddress) {
if (macroaddress >= 0) {
parsearglist();
byte thesym = sym; // save sym for restore
vpush(symval); // and symval
char *fetchmark = fetchptr; // save the current parse pointer
// call the macro
calleeprommacro(findend(macroaddress)); // register the macro into the parser stream
getsym(); // fetch its first symbol
numvar ret = getstatementlist(); // parse and execute the macro code here
// if (sym != s_eof) expected(M_eof);
// restore parsing context so we can resume cleanly
symval = vpop(); // restore symval
sym = thesym; // restore saved sym
releaseargblock(); // drop the args
fetchptr = fetchmark; // restore pointer
primec(); // and inchar
vpush(ret); // send back our return value
}
}
// Get a statement
void getstatement(void) {
#if !defined(TINY85)
chkbreak();
#endif
if (sym == s_while) {
// at this point sym is pointing at s_while, before the conditional expression
// save fetchptr so we can restart parsing from here as the while iterates
char *fetchmark = fetchptr;
for (;;) {
fetchptr = fetchmark; // restore to mark
primec(); // set up for mr. getsym()
getsym(); // fetch the start of the conditional
if (!getnum()) {
//longjmp(env, X_EXIT); // get the conditional; exit on false
sym = s_eof; // we're finished here. move along.
return;
}
if (sym != s_colon) expectedchar(':');
getsym(); // eat :
getstatementlist();
}
}
else if (sym == s_if) {
getsym(); // fetch the start of the conditional
if (!getnum()) {
//longjmp(env, X_EXIT); // get the conditional; exit on false
sym = s_eof;
return;
}
if (sym != s_colon) expectedchar(':');
getsym(); // eat :
getstatementlist();
}
#if SKETCH
// The switch statement: call one of N macros based on a selector value
// switch <numval>: macroid1, macroid2,.., macroidN
// numval < 0: numval = 0
// numval > N: numval = N
else if (sym == s_switch) {
getsym(); // eat "switch"
numvar selector = getnum(); // evaluate the switch value
if (selector < 0) selector = 0;
if (sym != s_colon) expectedchar(':');
// we sit before the first macroid
// scan and discard the <selector>'s worth of macro ids
// that sit before the one we want
for (;;) {
getsym(); // get an id, sets symval to its eeprom addr as a side effect
if (sym != s_macro) expected (6); // TODO: define M_macro instead of 6
getsym(); // eat id, get separator; assume symval is untouched
if ((sym == s_semi) || (sym == s_eof)) break; // last case is default so we exit always
if (sym != s_comma) expectedchar(',');
if (!selector) break; // ok, this is the one we want to execute
selector--; // one down...
}
// call the macro whose addr is squirreled in symval all this time
// on return, the parser is ready to pick up where we left off
doMacroCall(symval);
// scan past the rest of the unused switch options, if any
// TODO: syntax checking for non-chosen options could be made much tighter at the cost of some space
while ((sym != s_semi) && (sym != s_eof)) getsym(); // scan to end of statement without executing
}
#endif
else if ((sym == s_macro) || (sym == s_undef)) { // macro def or ref
getsym(); // scan past macro name to next symbol: ; or :=
if (sym == s_define) { // macro definition: macroid := strvalue
// to define the macro, we need to copy the id somewhere on the stack
// to avoid having this local buffer in every getstatement stack frame,
// we break out defineMacro here to a separate function that only eats that
// stack in the case that a macro is being defined
#ifdef TINY85
unexpected(M_defmacro);
#else
defineMacro();
#endif
}
else if ((sym == s_semi) || (sym == s_eof)) { // valid macro reference: let's call it
#if SKETCH
doMacroCall(symval); // parseid stashes the macro address in symval
#else
char op = sym; // save sym for restore
expval = findKey(idbuf); // assumes id in idbuf isn't clobbered since getsym() above
if (expval >= 0) {
char *fetchmark = fetchptr; // save the current parse pointer
// call the macro
calleeprommacro(findend(expval)); // register the macro into the parser stream
getsym();
getstatementlist(); // parse and execute the macro code here
if (sym != s_eof) expected(M_eof);
// restore parsing context so we can resume cleanly
fetchptr = fetchmark; // restore pointer
primec(); // and inchar
sym = op; // restore saved sym: s_semi or s_eof
} else unexpected(M_id);
#endif
}
else expectedchar(';');
//else getexpression(); // assume it was macro1+32+macro2...
}
else if (sym == s_run) { // run macroname
getsym();
if (sym != s_macro) unexpected(M_id);
#if 0
// address of macroid is in symval via parseid
startTask(kludge(symval));
getsym();
#else
// address of macroid is in symval via parseid
// check for [,snoozeintervalms]
getsym(); // eat macroid to check for comma; symval untouched
if (sym == s_comma) {
vpush(symval);
getsym(); // eat the comma
getnum(); // get a number or else
startTask(kludge(vpop()), expval);
}
else startTask(kludge(symval), 0);
#endif
}
else if (sym == s_stop) {
getsym();
if (sym == s_mul) { // stop * stops all tasks
initTaskList();
getsym();
}
else if ((sym == s_semi) || (sym == s_eof)) {
if (background) stopTask(curtask); // stop with no args stops the current task IF we're in back
else initTaskList(); // in foreground, stop all
}
else stopTask(getnum());
}
else if (sym == s_boot) reboot();
#if !defined(TINY85)
else if (sym == s_rm) { // rm "sym" or rm *
getsym();
if (sym == s_macro) {
eraseentry(idbuf);
}
else if (sym == s_mul) nukeeeprom();
else expected(M_id);
getsym();
}
else if (sym == s_ps) showTaskList();
else if (sym == s_peep) { getsym(); cmd_peep(); }
else if (sym == s_ls) { getsym(); cmd_ls(); }
else if (sym == s_help) { getsym(); cmd_help(); }
else if (sym == s_print) { getsym(); cmd_print(); }
#endif
#ifdef HEX_UPLOAD
// a line beginning with a colon is treated as a hex record
// containing data to upload to eeprom
//
// TODO: verify checksum
//
else if (sym == s_colon) {
// fetchptr points at the byte count
byte byteCount = gethex(2); // 2 bytes byte count
int addr = gethex(4); // 4 bytes address
byte recordType = gethex(2); // 2 bytes record type; now fetchptr -> data
if (recordType == 1) reboot(); // reboot on EOF record (01)
if (recordType != 0) return; // we only handle the data record (00)
if (addr == 0) nukeeeprom(); // auto-clear eeprom on write to 0000
while (byteCount--) eewrite(addr++, gethex(2)); // update the eeprom
gethex(2); // discard the checksum
getsym(); // and re-prime the parser
}
#endif
else {
getexpression();
}
}
