1 files changed, 125 insertions, 85 deletions

diff --git a/common/str.cpp b/common/str.cpp
index ad48ef6087..5f8d4ffb7e 100644
--- a/common/str.cpp
+++ b/common/str.cpp
@@ -43,32 +43,43 @@ static int computeCapacity(int len) {
 	return ((len + 32 - 1) & ~0x1F) - 1;
 }
 
-String::String(const char *str, uint32 len)
-: _len(0), _str(_storage) {
+String::String(const char *str) : _len(0), _str(_storage) {
+	if (str == 0) {
+		_storage[0] = 0;
+		_len = 0;
+	} else
+		initWithCStr(str, strlen(str));
+}
+
+String::String(const char *str, uint32 len) : _len(0), _str(_storage) {
+	initWithCStr(str, len);
+}
+
+String::String(const char *beginP, const char *endP) : _len(0), _str(_storage) {
+	assert(endP >= beginP);
+	initWithCStr(beginP, endP - beginP);
+}
+
+void String::initWithCStr(const char *str, uint32 len) {
+	assert(str);
 
 	// Init _storage member explicitly (ie. without calling its constructor)
 	// for GCC 2.95.x compatibility (see also tracker item #1602879).
 	_storage[0] = 0;
 
-	if (str && *str) {
-		const uint32 tmp = strlen(str);
-		assert(len <= tmp);
-		if (len <= 0)
-			len = tmp;
-		_len = len;
-
-		if (len >= _builtinCapacity) {
-			// Not enough internal storage, so allocate more
-			_extern._capacity = computeCapacity(len);
-			_extern._refCount = 0;
-			_str = (char *)malloc(_extern._capacity+1);
-			assert(_str != 0);
-		}
-
-		// Copy the string into the storage area
-		memcpy(_str, str, len);
-		_str[len] = 0;
+	_len = len;
+
+	if (len >= _builtinCapacity) {
+		// Not enough internal storage, so allocate more
+		_extern._capacity = computeCapacity(len);
+		_extern._refCount = 0;
+		_str = (char *)malloc(_extern._capacity+1);
+		assert(_str != 0);
 	}
+
+	// Copy the string into the storage area
+	memmove(_str, str, len);
+	_str[len] = 0;
 }
 
 String::String(const String &str)
@@ -91,6 +102,8 @@ String::String(char c)
 	_storage[0] = c;
 	_storage[1] = 0;
 
+	// TODO/FIXME: There is no reason for the following check -- we *do*
+	// allow strings to contain 0 bytes!
 	_len = (c == 0) ? 0 : 1;
 }
 
@@ -98,6 +111,74 @@ String::~String() {
 	decRefCount(_extern._refCount);
 }
 
+void String::makeUnique() {
+	ensureCapacity(_len, true);
+}
+
+/**
+ * Ensure that enough storage is available to store at least new_len
+ * characters plus a null byte. In addition, if we currently share
+ * the storage with another string, unshare it, so that we can safely
+ * write to the storage.
+ */
+void String::ensureCapacity(uint32 new_len, bool keep_old) {
+	bool isShared;
+	uint32 curCapacity, newCapacity;
+	char *newStorage;
+	int *oldRefCount = _extern._refCount;
+
+	if (isStorageIntern()) {
+		isShared = false;
+		curCapacity = _builtinCapacity - 1;
+	} else {
+		isShared = (oldRefCount && *oldRefCount > 1);
+		curCapacity = _extern._capacity;
+	}
+
+	// Special case: If there is enough space, and we do not share
+	// the storage, then there is nothing to do.
+	if (!isShared && new_len <= curCapacity)
+		return;
+
+	if (isShared && new_len <= _builtinCapacity - 1) {
+		// We share the storage, but there is enough internal storage: Use that.
+		newStorage = _storage;
+		newCapacity = _builtinCapacity - 1;
+	} else {
+		// We need to allocate storage on the heap!
+
+		// Compute a suitable new capacity limit
+		newCapacity = computeCapacity(new_len);
+
+		// Allocate new storage
+		newStorage = (char *)malloc(newCapacity+1);
+		assert(newStorage);
+	}
+
+	// Copy old data if needed, elsewise reset the new storage.
+	if (keep_old) {
+		assert(_len <= newCapacity);
+		memcpy(newStorage, _str, _len + 1);
+	} else {
+		_len = 0;
+		newStorage[0] = 0;
+	}
+
+	// Release hold on the old storage ...
+	decRefCount(oldRefCount);
+
+	// ... in favor of the new storage
+	_str = newStorage;
+
+	if (!isStorageIntern()) {
+		// Set the ref count & capacity if we use an external storage.
+		// It is important to do this *after* copying any old content,
+		// else we would override data that has not yet been copied!
+		_extern._refCount = 0;
+		_extern._capacity = newCapacity;
+	}
+}
+
 void String::incRefCount() const {
 	assert(!isStorageIntern());
 	if (_extern._refCount == 0) {
@@ -130,11 +211,14 @@ String& String::operator  =(const char *str) {
 	uint32 len = strlen(str);
 	ensureCapacity(len, false);
 	_len = len;
-	memcpy(_str, str, len + 1);
+	memmove(_str, str, len + 1);
 	return *this;
 }
 
 String &String::operator  =(const String &str) {
+	if (&str == this)
+		return *this;
+
 	if (str.isStorageIntern()) {
 		decRefCount(_extern._refCount);
 		_len = str._len;
@@ -154,7 +238,8 @@ String &String::operator  =(const String &str) {
 }
 
 String& String::operator  =(char c) {
-	ensureCapacity(1, false);
+	decRefCount(_extern._refCount);
+	_str = _storage;
 	_len = 1;
 	_str[0] = c;
 	_str[1] = 0;
@@ -237,10 +322,7 @@ void String::deleteLastChar() {
 void String::deleteChar(uint32 p) {
 	assert(p < _len);
 
-	// Call ensureCapacity to make sure we actually *own* the storage
-	// to which _str points to -- we wouldn't want to modify a storage
-	// which other string objects are sharing, after all.
-	ensureCapacity(_len, true);
+	makeUnique();
 	while (p++ < _len)
 		_str[p-1] = _str[p];
 	_len--;
@@ -257,7 +339,7 @@ void String::clear() {
 void String::setChar(char c, uint32 p) {
 	assert(p <= _len);
 
-	ensureCapacity(_len, true);
+	makeUnique();
 	_str[p] = c;
 }
 
@@ -272,78 +354,36 @@ void String::insertChar(char c, uint32 p) {
 }
 
 void String::toLowercase() {
-	ensureCapacity(_len, true);
+	makeUnique();
 	for (uint32 i = 0; i < _len; ++i)
 		_str[i] = tolower(_str[i]);
 }
 
 void String::toUppercase() {
-	ensureCapacity(_len, true);
+	makeUnique();
 	for (uint32 i = 0; i < _len; ++i)
 		_str[i] = toupper(_str[i]);
 }
 
-/**
- * Ensure that enough storage is available to store at least new_len
- * characters plus a null byte. In addition, if we currently share
- * the storage with another string, unshare it, so that we can safely
- * write to the storage.
- */
-void String::ensureCapacity(uint32 new_len, bool keep_old) {
-	bool isShared;
-	uint32 curCapacity, newCapacity;
-	char *newStorage;
-	int *oldRefCount = _extern._refCount;
-
-	if (isStorageIntern()) {
-		isShared = false;
-		curCapacity = _builtinCapacity - 1;
-	} else {
-		isShared = (oldRefCount && *oldRefCount > 1);
-		curCapacity = _extern._capacity;
-	}
-
-	// Special case: If there is enough space, and we do not share
-	// the storage, then there is nothing to do.
-	if (!isShared && new_len <= curCapacity)
+void String::trim() {
+	if (_len == 0)
 		return;
 
-	if (isShared && new_len <= _builtinCapacity - 1) {
-		// We share the storage, but there is enough internal storage: Use that.
-		newStorage = _storage;
-		newCapacity = _builtinCapacity - 1;
-	} else {
-		// We need to allocate storage on the heap!
-
-		// Compute a suitable new capacity limit
-		newCapacity = computeCapacity(new_len);
-
-		// Allocate new storage
-		newStorage = (char *)malloc(newCapacity+1);
-		assert(newStorage);
-	}
-
-	// Copy old data if needed, elsewise reset the new storage.
-	if (keep_old) {
-		assert(_len <= newCapacity);
-		memcpy(newStorage, _str, _len + 1);
-	} else {
-		_len = 0;
-		newStorage[0] = 0;
-	}
+	makeUnique();
 
-	// Release hold on the old storage ...
-	decRefCount(oldRefCount);
+	// Trim trailing whitespace
+	while (_len >= 1 && isspace(_str[_len-1]))
+		_len--;
+	_str[_len] = 0;
 
-	// ... in favor of the new storage
-	_str = newStorage;
+	// Trim leading whitespace
+	char *t = _str;
+	while (isspace(*t))
+		t++;
 
-	if (!isStorageIntern()) {
-		// Set the ref count & capacity if we use an external storage.
-		// It is important to do this *after* copying any old content,
-		// else we would override data that has not yet been copied!
-		_extern._refCount = 0;
-		_extern._capacity = newCapacity;
+	if (t != _str) {
+		_len -= t - _str;
+		memmove(_str, t, _len + 1);
 	}
 }