Invalid read return value fix

earlephilhower · earlephilhower · commit 9968dce1f5d1 · 2021-01-08T08:35:35.000-08:00
Fixes esp8266#7814. Return 0, not MAXINT, when a read is called on a File without a backing instance of a SPIFFS/LittleFS/SD File.
diff --git a/cores/esp8266/FS.cpp b/cores/esp8266/FS.cpp
@@ -68,7 +68,7 @@ int File::read() {
 
 size_t File::read(uint8_t* buf, size_t size) {
     if (!_p)
-        return -1;
+        return 0;
 
     return _p->read(buf, size);
 }

Original file line number	Diff line number	Diff line change
`@@ -68,7 +68,7 @@ int File::read() {`
`68`	`68`
`69`	`69`	`size_t File::read(uint8_t* buf, size_t size) {`
`70`	`70`	`if (!_p)`
`71`		`- return -1;`
	`71`	`+ return 0;`
`72`	`72`
`73`	`73`	`return _p->read(buf, size);`
`74`	`74`	`}`