int nativeCallGetCType(JsLex *lex) {
if (lex->tk == LEX_R_VOID) {
jslMatch(lex, LEX_R_VOID);
return JSWAT_VOID;
}
if (lex->tk == LEX_ID) {
int t = -1;
char *name = jslGetTokenValueAsString(lex);
if (strcmp(name,"int")==0) t=JSWAT_INT32;
if (strcmp(name,"double")==0) t=JSWAT_JSVARFLOAT;
if (strcmp(name,"bool")==0) t=JSWAT_BOOL;
if (strcmp(name,"Pin")==0) t=JSWAT_PIN;
if (strcmp(name,"JsVar")==0) t=JSWAT_JSVAR;
jslMatch(lex, LEX_ID);
return t;
}
return -1; // unknown
}
/*JSON{
"type" : "staticmethod",
"ifndef" : "SAVE_ON_FLASH",
"class" : "E",
"name" : "nativeCall",
"generate" : "jswrap_espruino_nativeCall",
"params" : [
["addr","int","The address in memory of the function"],
["sig","JsVar","The signature of the call, `returnType (arg1,arg2,...)`. Allowed types are `void`,`bool`,`int`,`double`,`Pin`,`JsVar`"]
],
"return" : ["JsVar","The native function"]
}
ADVANCED: This is a great way to crash Espruino if you're not sure what you are doing
Create a native function that executes the code at the given address. Eg. `E.nativeCall(0x08012345,'double (double,double)')(1.1, 2.2)`
If you're executing a thumb function, you'll almost certainly need to set the bottom bit of the address to 1.
Note it's not guaranteed that the call signature you provide can be used - it has to be something that a function in Espruino already uses.
*/
JsVar *jswrap_espruino_nativeCall(JsVarInt addr, JsVar *signature) {
unsigned int argTypes = 0;
if (jsvIsUndefined(signature)) {
// Nothing to do
} else if (jsvIsString(signature)) {
JsLex lex;
jslInit(&lex, signature);
int argType;
bool ok = true;
int argNumber = 0;
argType = nativeCallGetCType(&lex);
if (argType>=0) argTypes |= (unsigned)argType << (JSWAT_BITS * argNumber++);
else ok = false;
if (ok) ok = jslMatch(&lex, '(');
while (ok && lex.tk!=LEX_EOF && lex.tk!=')') {
argType = nativeCallGetCType(&lex);
if (argType>=0) {
argTypes |= (unsigned)argType << (JSWAT_BITS * argNumber++);
if (lex.tk!=')') ok = jslMatch(&lex, ',');
} else ok = false;
}
if (ok) ok = jslMatch(&lex, ')');
jslKill(&lex);
if (argTypes & (unsigned int)~0xFFFF)
ok = false;
if (!ok) {
jsExceptionHere(JSET_ERROR, "Error Parsing signature at argument number %d", argNumber);
return 0;
}
} else {
jsExceptionHere(JSET_ERROR, "Invalid Signature");
return 0;
}
return jsvNewNativeFunction((void *)(size_t)addr, (unsigned short)argTypes);
}
JsVar *jswrap_json_parse_internal() {
switch (lex->tk) {
case LEX_R_TRUE: jslGetNextToken(lex); return jsvNewFromBool(true);
case LEX_R_FALSE: jslGetNextToken(lex); return jsvNewFromBool(false);
case LEX_R_NULL: jslGetNextToken(lex); return jsvNewWithFlags(JSV_NULL);
case '-': {
jslGetNextToken(lex);
if (lex->tk!=LEX_INT && lex->tk!=LEX_FLOAT) return 0;
JsVar *v = jswrap_json_parse_internal(lex);
JsVar *zero = jsvNewFromInteger(0);
JsVar *r = jsvMathsOp(zero, v, '-');
jsvUnLock2(v, zero);
return r;
}
case LEX_INT: {
long long v = stringToInt(jslGetTokenValueAsString(lex));
jslGetNextToken(lex);
return jsvNewFromLongInteger(v);
}
case LEX_FLOAT: {
JsVarFloat v = stringToFloat(jslGetTokenValueAsString(lex));
jslGetNextToken(lex);
return jsvNewFromFloat(v);
}
case LEX_STR: {
JsVar *a = jslGetTokenValueAsVar(lex);
jslGetNextToken(lex);
return a;
}
case '[': {
JsVar *arr = jsvNewEmptyArray(); if (!arr) return 0;
jslGetNextToken(lex); // [
while (lex->tk != ']' && !jspHasError()) {
JsVar *value = jswrap_json_parse_internal(lex);
if (!value ||
(lex->tk!=']' && !jslMatch(','))) {
jsvUnLock2(value, arr);
return 0;
}
jsvArrayPush(arr, value);
jsvUnLock(value);
}
if (!jslMatch(']')) {
jsvUnLock(arr);
return 0;
}
return arr;
}
case '{': {
JsVar *obj = jsvNewObject(); if (!obj) return 0;
jslGetNextToken(lex); // {
while (lex->tk == LEX_STR && !jspHasError()) {
JsVar *key = jsvAsArrayIndexAndUnLock(jslGetTokenValueAsVar(lex));
jslGetNextToken(lex);
JsVar *value = 0;
if (!jslMatch(':') ||
!(value=jswrap_json_parse_internal(lex)) ||
(lex->tk!='}' && !jslMatch(','))) {
jsvUnLock3(key, value, obj);
return 0;
}
jsvAddName(obj, jsvMakeIntoVariableName(key, value));
jsvUnLock2(value, key);
}
if (!jslMatch('}')) {
jsvUnLock(obj);
return 0;
}
return obj;
}
default: {
char buf[32];
jslTokenAsString(lex->tk, buf, 32);
jsExceptionHere(JSET_SYNTAXERROR, "Expecting a valid value, got %s", buf);
return 0; // undefined = error
}
}
}
JsVar *jswrap_json_parse_internal(JsLex *lex) {
switch (lex->tk) {
case LEX_R_TRUE: jslGetNextToken(lex); return jsvNewFromBool(true);
case LEX_R_FALSE: jslGetNextToken(lex); return jsvNewFromBool(false);
case LEX_R_NULL: jslGetNextToken(lex); return jsvNewWithFlags(JSV_NULL);
case '-': {
jslGetNextToken(lex);
if (lex->tk!=LEX_INT && lex->tk!=LEX_FLOAT) return 0;
JsVar *v = jswrap_json_parse_internal(lex);
JsVar *zero = jsvNewFromInteger(0);
JsVar *r = jsvMathsOp(zero, v, '-');
jsvUnLock(v);
jsvUnLock(zero);
return r;
}
case LEX_INT: {
long long v = stringToInt(jslGetTokenValueAsString(lex));
jslGetNextToken(lex);
return jsvNewFromLongInteger(v);
}
case LEX_FLOAT: {
JsVarFloat v = stringToFloat(jslGetTokenValueAsString(lex));
jslGetNextToken(lex);
return jsvNewFromFloat(v);
}
case LEX_STR: {
JsVar *a = jslGetTokenValueAsVar(lex);
jslGetNextToken(lex);
return a;
}
case '[': {
JsVar *arr = jsvNewWithFlags(JSV_ARRAY); if (!arr) return 0;
jslGetNextToken(lex); // [
while (lex->tk != ']') {
JsVar *value = jswrap_json_parse_internal(lex);
if (!value ||
(lex->tk!=']' && !jslMatch(lex, ','))) {
jsvUnLock(value);
jsvUnLock(arr);
return 0;
}
jsvArrayPush(arr, value);
jsvUnLock(value);
}
if (!jslMatch(lex, ']')) {
jsvUnLock(arr);
return 0;
}
return arr;
}
case '{': {
JsVar *obj = jsvNewWithFlags(JSV_OBJECT); if (!obj) return 0;
jslGetNextToken(lex); // {
while (lex->tk == LEX_STR) {
JsVar *key = jsvAsArrayIndexAndUnLock(jslGetTokenValueAsVar(lex));
jslGetNextToken(lex);
JsVar *value = 0;
if (!jslMatch(lex, ':') ||
!(value=jswrap_json_parse_internal(lex)) ||
(lex->tk!='}' && !jslMatch(lex, ','))) {
jsvUnLock(key);
jsvUnLock(value);
jsvUnLock(obj);
return 0;
}
jsvAddName(obj, jsvMakeIntoVariableName(key, value));
jsvUnLock(value);
jsvUnLock(key);
}
if (!jslMatch(lex, '}')) {
jsvUnLock(obj);
return 0;
}
return obj;
}
default: return 0; // undefined = error
}
}
