// Get a statement
numvar getstatement(void) {
numvar retval = 0;
//char *fetchmark;
numvar fetchmark;
chkbreak();
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
//fetchmark = fetchptr;
fetchmark = markparsepoint();
for (;;) {
//fetchptr = fetchmark; // restore to mark
//primec(); // set up for mr. getsym()
returntoparsepoint(fetchmark, 0);
getsym(); // fetch the start of the conditional
if (getnum()) {
retval = getstatement();
if (sym == s_returning) break; // exit if we caught a return
}
else {
skipstatement();
break;
}
}
}
else if (sym == s_if) {
getsym(); // eat "if"
if (getnum()) {
retval = getstatement();
if (sym == s_else) {
getsym(); // eat "else"
skipstatement();
}
} else {
skipstatement();
if (sym == s_else) {
getsym(); // eat "else"
retval = getstatement();
}
}
}
else if (sym == s_lcurly) {
getsym(); // eat "{"
while ((sym != s_eof) && (sym != s_returning) && (sym != s_rcurly)) retval = getstatement();
if (sym == s_rcurly) getsym(); // eat "}"
}
else if (sym == s_return) {
getsym(); // eat "return"
if ((sym != s_eof) && (sym != s_semi)) retval = getnum();
sym = s_returning; // signal we're returning up the line
}
else if (sym == s_switch) retval = getswitchstatement();
else if (sym == s_function) cmd_function();
else if (sym == s_run) { // run macroname
getsym();
if ((sym != s_script_eeprom) && (sym != s_script_progmem) &&
(sym != s_script_file)) unexpected(M_id);
// 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(vpop(), expval);
}
else startTask(symval, 0);
}
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();
else if (sym == s_rm) { // rm "sym" or rm *
getsym();
if (sym == s_script_eeprom) {
eraseentry(idbuf);
}
else if (sym == s_mul) nukeeeprom();
else if (sym != s_undef) expected(M_id);
getsym();
}
else if (sym == s_ps) { getsym(); 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(); }
else if (sym == s_semi) { ; } // ;)
#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();
if (sym == s_semi) getsym(); // eat trailing ';'
return retval;
}
// Get a statement
numvar getstatement(void) {
numvar retval = 0;
char *fetchmark;
chkbreak();
//#define LINEMODE
#ifdef LINEMODE
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();
}
// 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
}
#else
// new statement handling
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
fetchmark = fetchptr;
for (;;) {
fetchptr = fetchmark; // restore to mark
primec(); // set up for mr. getsym()
getsym(); // fetch the start of the conditional
if (getnum()) {
retval = getstatement();
if (sym == s_returning) break; // exit if we caught a return
}
else {
skipstatement();
break;
}
}
}
else if (sym == s_if) {
getsym(); // eat "if"
if (getnum()) {
retval = getstatement();
if (sym == s_else) {
getsym(); // eat "else"
skipstatement();
}
} else {
skipstatement();
if (sym == s_else) {
getsym(); // eat "else"
retval = getstatement();
}
}
}
else if (sym == s_lcurly) {
getsym(); // eat "{"
while ((sym != s_eof) && (sym != s_returning) && (sym != s_rcurly)) retval = getstatement();
if (sym == s_rcurly) getsym(); // eat "}"
}
else if (sym == s_return) {
getsym(); // eat "return"
if ((sym != s_eof) && (sym != s_semi)) retval = getnum();
sym = s_returning; // signal we're returning up the line
}
else if (sym == s_switch) retval = getswitchstatement();
else if (sym == s_function) cmd_function();
#endif
else if (sym == s_run) { // run macroname
getsym();
if (sym != s_macro) unexpected(M_id);
// 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);
}
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 if (sym != s_undef) expected(M_id);
getsym();
}
else if (sym == s_ps) { getsym(); 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(); }
else if (sym == s_semi) { ; } // ;)
#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();
if (sym == s_semi) getsym(); // eat trailing ';'
return retval;
}