Remove strlen in calls like String::concat(s, strlen(s))

matthijskooijman · matthijskooijman · commit 184dd3e812fe · 2021-01-25T10:04:20.000+01:00
Instead of calling strlen in a dozen places, instead just call
String::concat(s), which will then call strlen. This shrinks the code
size of these calls significantly, the StringAppendOperator example on
the Arduino Uno shrinks by 72 bytes. This change does incur a slight
runtime cost, because there is one extra function call.
diff --git a/api/String.cpp b/api/String.cpp
@@ -307,49 +307,49 @@ unsigned char String::concat(unsigned char num)
 {
 	char buf[1 + 3 * sizeof(unsigned char)];
 	itoa(num, buf, 10);
-	return concat(buf, strlen(buf));
+	return concat(buf);
 }
 
 unsigned char String::concat(int num)
 {
 	char buf[2 + 3 * sizeof(int)];
 	itoa(num, buf, 10);
-	return concat(buf, strlen(buf));
+	return concat(buf);
 }
 
 unsigned char String::concat(unsigned int num)
 {
 	char buf[1 + 3 * sizeof(unsigned int)];
 	utoa(num, buf, 10);
-	return concat(buf, strlen(buf));
+	return concat(buf);
 }
 
 unsigned char String::concat(long num)
 {
 	char buf[2 + 3 * sizeof(long)];
 	ltoa(num, buf, 10);
-	return concat(buf, strlen(buf));
+	return concat(buf);
 }
 
 unsigned char String::concat(unsigned long num)
 {
 	char buf[1 + 3 * sizeof(unsigned long)];
 	ultoa(num, buf, 10);
-	return concat(buf, strlen(buf));
+	return concat(buf);
 }
 
 unsigned char String::concat(float num)
 {
 	char buf[20];
 	char* string = dtostrf(num, 4, 2, buf);
-	return concat(string, strlen(string));
+	return concat(string);
 }
 
 unsigned char String::concat(double num)
 {
 	char buf[20];
 	char* string = dtostrf(num, 4, 2, buf);
-	return concat(string, strlen(string));
+	return concat(string);
 }
 
 unsigned char String::concat(const __FlashStringHelper * str)
@@ -378,7 +378,7 @@ StringSumHelper & operator + (const StringSumHelper &lhs, const String &rhs)
 StringSumHelper & operator + (const StringSumHelper &lhs, const char *cstr)
 {
 	StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
-	if (!cstr || !a.concat(cstr, strlen(cstr))) a.invalidate();
+	if (!cstr || !a.concat(cstr)) a.invalidate();
 	return a;
 }
 

Original file line number	Diff line number	Diff line change
`@@ -307,49 +307,49 @@ unsigned char String::concat(unsigned char num)`
`307`	`307`	`{`
`308`	`308`	`char buf[1 + 3 * sizeof(unsigned char)];`
`309`	`309`	`itoa(num, buf, 10);`
`310`		`- return concat(buf, strlen(buf));`
	`310`	`+ return concat(buf);`
`311`	`311`	`}`
`312`	`312`
`313`	`313`	`unsigned char String::concat(int num)`
`314`	`314`	`{`
`315`	`315`	`char buf[2 + 3 * sizeof(int)];`
`316`	`316`	`itoa(num, buf, 10);`
`317`		`- return concat(buf, strlen(buf));`
	`317`	`+ return concat(buf);`
`318`	`318`	`}`
`319`	`319`
`320`	`320`	`unsigned char String::concat(unsigned int num)`
`321`	`321`	`{`
`322`	`322`	`char buf[1 + 3 * sizeof(unsigned int)];`
`323`	`323`	`utoa(num, buf, 10);`
`324`		`- return concat(buf, strlen(buf));`
	`324`	`+ return concat(buf);`
`325`	`325`	`}`
`326`	`326`
`327`	`327`	`unsigned char String::concat(long num)`
`328`	`328`	`{`
`329`	`329`	`char buf[2 + 3 * sizeof(long)];`
`330`	`330`	`ltoa(num, buf, 10);`
`331`		`- return concat(buf, strlen(buf));`
	`331`	`+ return concat(buf);`
`332`	`332`	`}`
`333`	`333`
`334`	`334`	`unsigned char String::concat(unsigned long num)`
`335`	`335`	`{`
`336`	`336`	`char buf[1 + 3 * sizeof(unsigned long)];`
`337`	`337`	`ultoa(num, buf, 10);`
`338`		`- return concat(buf, strlen(buf));`
	`338`	`+ return concat(buf);`
`339`	`339`	`}`
`340`	`340`
`341`	`341`	`unsigned char String::concat(float num)`
`342`	`342`	`{`
`343`	`343`	`char buf[20];`
`344`	`344`	`char* string = dtostrf(num, 4, 2, buf);`
`345`		`- return concat(string, strlen(string));`
	`345`	`+ return concat(string);`
`346`	`346`	`}`
`347`	`347`
`348`	`348`	`unsigned char String::concat(double num)`
`349`	`349`	`{`
`350`	`350`	`char buf[20];`
`351`	`351`	`char* string = dtostrf(num, 4, 2, buf);`
`352`		`- return concat(string, strlen(string));`
	`352`	`+ return concat(string);`
`353`	`353`	`}`
`354`	`354`
`355`	`355`	`unsigned char String::concat(const __FlashStringHelper * str)`
`@@ -378,7 +378,7 @@ StringSumHelper & operator + (const StringSumHelper &lhs, const String &rhs)`
`378`	`378`	`StringSumHelper & operator + (const StringSumHelper &lhs, const char *cstr)`
`379`	`379`	`{`
`380`	`380`	`StringSumHelper &a = const_cast<StringSumHelper&>(lhs);`
`381`		`- if (!cstr \|\| !a.concat(cstr, strlen(cstr))) a.invalidate();`
	`381`	`+ if (!cstr \|\| !a.concat(cstr)) a.invalidate();`
`382`	`382`	`return a;`
`383`	`383`	`}`
`384`	`384`