propset.cxx

Wxpython Implemented on Windows CE, Source code

		lenKey = static_cast<int>(strlen(key));
	unsigned int hash = HashString(key, lenKey);
	Property *pPrev = NULL;
	for (Property *p = props[hash % hashRoots]; p; p = p->next) {
		if ((hash == p->hash) &&
			((strlen(p->key) == static_cast<unsigned int>(lenKey)) &&
				(0 == strncmp(p->key, key, lenKey)))) {
			if (pPrev)
				pPrev->next = p->next;
			else
				props[hash % hashRoots] = p->next;
			if (p == enumnext)
				enumnext = p->next; // Not that anyone should mix enum and Set / Unset.
			delete [](p->key);
			delete [](p->val);
			delete p;
			return;
		} else {
			pPrev = p;
		}
	}
}

void PropSet::SetMultiple(const char *s) {
	const char *eol = strchr(s, '\n');
	while (eol) {
		Set(s);
		s = eol + 1;
		eol = strchr(s, '\n');
	}
	Set(s);
}

SString PropSet::Get(const char *key) {
	unsigned int hash = HashString(key, strlen(key));
	for (Property *p = props[hash % hashRoots]; p; p = p->next) {
		if ((hash == p->hash) && (0 == strcmp(p->key, key))) {
			return p->val;
		}
	}
	if (superPS) {
		// Failed here, so try in base property set
		return superPS->Get(key);
	} else {
		return "";
	}
}

bool PropSet::IncludesVar(const char *value, const char *key) {
	const char *var = strstr(value, "$(");
	while (var) {
		if (isprefix(var + 2, key) && (var[2 + strlen(key)] == ')')) {
			// Found $(key) which would lead to an infinite loop so exit
			return true;
		}
		var = strstr(var + 2, ")");
		if (var)
			var = strstr(var + 1, "$(");
	}
	return false;
}


// There is some inconsistency between GetExpanded("foo") and Expand("$(foo)").
// A solution is to keep a stack of variables that have been expanded, so that
// recursive expansions can be skipped.  For now I'll just use the C++ stack
// for that, through a recursive function and a simple chain of pointers.

struct VarChain {
	VarChain(const char*var_=NULL, const VarChain *link_=NULL): var(var_), link(link_) {}

	bool contains(const char *testVar) const {
		return (var && (0 == strcmp(var, testVar)))
			|| (link && link->contains(testVar));
	}

	const char *var;
	const VarChain *link;
};

static int ExpandAllInPlace(PropSet &props, SString &withVars, int maxExpands, const VarChain &blankVars = VarChain()) {
	int varStart = withVars.search("$(");
	while ((varStart >= 0) && (maxExpands > 0)) {
		int varEnd = withVars.search(")", varStart+2);
		if (varEnd < 0) {
			break;
		}

		// For consistency, when we see '$(ab$(cde))', expand the inner variable first,
		// regardless whether there is actually a degenerate variable named 'ab$(cde'.
		int innerVarStart = withVars.search("$(", varStart+2);
		while ((innerVarStart > varStart) && (innerVarStart < varEnd)) {
			varStart = innerVarStart;
			innerVarStart = withVars.search("$(", varStart+2);
		}

		SString var(withVars.c_str(), varStart + 2, varEnd);
		SString val = props.Get(var.c_str());

		if (blankVars.contains(var.c_str())) {
			val.clear(); // treat blankVar as an empty string (e.g. to block self-reference)
		}

		if (--maxExpands >= 0) {
			maxExpands = ExpandAllInPlace(props, val, maxExpands, VarChain(var.c_str(), &blankVars));
		}

		withVars.remove(varStart, varEnd-varStart+1);
		withVars.insert(varStart, val.c_str(), val.length());

		varStart = withVars.search("$(");
	}

	return maxExpands;
}


SString PropSet::GetExpanded(const char *key) {
	SString val = Get(key);
	ExpandAllInPlace(*this, val, 100, VarChain(key));
	return val;
}

SString PropSet::Expand(const char *withVars, int maxExpands) {
	SString val = withVars;
	ExpandAllInPlace(*this, val, maxExpands);
	return val;
}

int PropSet::GetInt(const char *key, int defaultValue) {
	SString val = GetExpanded(key);
	if (val.length())
		return val.value();
	return defaultValue;
}

bool isprefix(const char *target, const char *prefix) {
	while (*target && *prefix) {
		if (*target != *prefix)
			return false;
		target++;
		prefix++;
	}
	if (*prefix)
		return false;
	else
		return true;
}

static bool IsSuffix(const char *target, const char *suffix, bool caseSensitive) {
	size_t lentarget = strlen(target);
	size_t lensuffix = strlen(suffix);
	if (lensuffix > lentarget)
		return false;
	if (caseSensitive) {
		for (int i = static_cast<int>(lensuffix) - 1; i >= 0; i--) {
			if (target[i + lentarget - lensuffix] != suffix[i])
				return false;
		}
	} else {
	for (int i = static_cast<int>(lensuffix) - 1; i >= 0; i--) {
		if (MakeUpperCase(target[i + lentarget - lensuffix]) !=
		        MakeUpperCase(suffix[i]))
			return false;
	}
	}
	return true;
}

SString PropSet::GetWild(const char *keybase, const char *filename) {
	for (int root = 0; root < hashRoots; root++) {
		for (Property *p = props[root]; p; p = p->next) {
			if (isprefix(p->key, keybase)) {
				char * orgkeyfile = p->key + strlen(keybase);
				char *keyfile = NULL;

				if (strstr(orgkeyfile, "$(") == orgkeyfile) {
					char *cpendvar = strchr(orgkeyfile, ')');
					if (cpendvar) {
						*cpendvar = '\0';
						SString s = GetExpanded(orgkeyfile + 2);
						*cpendvar = ')';
						keyfile = StringDup(s.c_str());
					}
				}
				char *keyptr = keyfile;

				if (keyfile == NULL)
					keyfile = orgkeyfile;

				for (;;) {
					char *del = strchr(keyfile, ';');
					if (del == NULL)
						del = keyfile + strlen(keyfile);
					char delchr = *del;
					*del = '\0';
					if (*keyfile == '*') {
						if (IsSuffix(filename, keyfile + 1, caseSensitiveFilenames)) {
							*del = delchr;
							delete []keyptr;
							return p->val;
						}
					} else if (0 == strcmp(keyfile, filename)) {
						*del = delchr;
						delete []keyptr;
						return p->val;
					}
					if (delchr == '\0')
						break;
					*del = delchr;
					keyfile = del + 1;
				}
				delete []keyptr;

				if (0 == strcmp(p->key, keybase)) {
					return p->val;
				}
			}
		}
	}
	if (superPS) {
		// Failed here, so try in base property set
		return superPS->GetWild(keybase, filename);
	} else {
		return "";
	}
}



// GetNewExpand does not use Expand as it has to use GetWild with the filename for each
// variable reference found.
SString PropSet::GetNewExpand(const char *keybase, const char *filename) {
	char *base = StringDup(GetWild(keybase, filename).c_str());
	char *cpvar = strstr(base, "$(");
	int maxExpands = 1000;	// Avoid infinite expansion of recursive definitions
	while (cpvar && (maxExpands > 0)) {
		char *cpendvar = strchr(cpvar, ')');
		if (cpendvar) {
			int lenvar = cpendvar - cpvar - 2;  	// Subtract the $()
			char *var = StringDup(cpvar + 2, lenvar);
			SString val = GetWild(var, filename);
			if (0 == strcmp(var, keybase))
				val.clear(); // Self-references evaluate to empty string
			size_t newlenbase = strlen(base) + val.length() - lenvar;
			char *newbase = new char[newlenbase];
			strncpy(newbase, base, cpvar - base);
			strcpy(newbase + (cpvar - base), val.c_str());
			strcpy(newbase + (cpvar - base) + val.length(), cpendvar + 1);
			delete []var;
			delete []base;
			base = newbase;
		}
		cpvar = strstr(base, "$(");
		maxExpands--;
	}
	SString sret = base;
	delete []base;
	return sret;
}

void PropSet::Clear() {
	for (int root = 0; root < hashRoots; root++) {
		Property *p = props[root];
		while (p) {
			Property *pNext = p->next;
			p->hash = 0;
			delete []p->key;
			p->key = 0;
			delete []p->val;
			p->val = 0;
			delete p;
			p = pNext;
		}
		props[root] = 0;
	}
}

char *PropSet::ToString() {
	size_t len=0;
	for (int r = 0; r < hashRoots; r++) {
		for (Property *p = props[r]; p; p = p->next) {
			len += strlen(p->key) + 1;
			len += strlen(p->val) + 1;
		}
	}
	if (len == 0)
		len = 1;	// Return as empty string
	char *ret = new char [len];
	if (ret) {
		char *w = ret;
		for (int root = 0; root < hashRoots; root++) {
			for (Property *p = props[root]; p; p = p->next) {
				strcpy(w, p->key);
				w += strlen(p->key);
				*w++ = '=';
				strcpy(w, p->val);
				w += strlen(p->val);
				*w++ = '\n';
			}
		}
		ret[len-1] = '\0';
	}
	return ret;
}

/**
 * Initiate enumeration.
 */
bool PropSet::GetFirst(char **key, char **val) {
	for (int i = 0; i < hashRoots; i++) {
		for (Property *p = props[i]; p; p = p->next) {
			if (p) {
				*key = p->key;
				*val = p->val;
				enumnext = p->next; // GetNext will begin here ...
				enumhash = i;		  // ... in this block
				return true;
			}
		}
	}
	return false;
}

/**
 * Continue enumeration.
 */
bool PropSet::GetNext(char ** key, char ** val) {
	bool firstloop = true;

	// search begins where we left it : in enumhash block
	for (int i = enumhash; i < hashRoots; i++) {
		if (!firstloop)
			enumnext = props[i]; // Begin with first property in block
		// else : begin where we left
		firstloop = false;

		for (Property *p = enumnext; p; p = p->next) {
			if (p) {
				*key = p->key;
				*val = p->val;
				enumnext = p->next; // for GetNext
				enumhash = i;
				return true;
			}
		}
	}
	return false;
}

/**
 * Creates an array that points into each word in the string and puts \0 terminators
 * after each word.
 */
static char **ArrayFromWordList(char *wordlist, int *len, bool onlyLineEnds = false) {
	int prev = '\n';
	int words = 0;
	// For rapid determination of whether a character is a separator, build
	// a look up table.
	bool wordSeparator[256];
	for (int i=0;i<256; i++) {
		wordSeparator[i] = false;
	}
	wordSeparator['\r'] = true;
	wordSeparator['\n'] = true;
	if (!onlyLineEnds) {
		wordSeparator[' '] = true;
		wordSeparator['\t'] = true;
	}
	for (int j = 0; wordlist[j]; j++) {
		int curr = static_cast<unsigned char>(wordlist[j]);
		if (!wordSeparator[curr] && wordSeparator[prev])
			words++;
		prev = curr;
	}
	char **keywords = new char *[words + 1];
	if (keywords) {
		words = 0;
		prev = '\0';
		size_t slen = strlen(wordlist);
		for (size_t k = 0; k < slen; k++) {
			if (!wordSeparator[static_cast<unsigned char>(wordlist[k])]) {
				if (!prev) {
					keywords[words] = &wordlist[k];
					words++;
				}
			} else {
				wordlist[k] = '\0';
			}
			prev = wordlist[k];
		}