* applied parts of the string speedup patch from debian #319377 (ABI change)

12 files changed, 102 insertions, 102 deletions

diff --git a/apt-pkg/contrib/configuration.cc b/apt-pkg/contrib/configuration.cc
index 09e454be9..14a000fa5 100644
--- a/apt-pkg/contrib/configuration.cc
+++ b/apt-pkg/contrib/configuration.cc
@@ -110,7 +110,7 @@ Configuration::Item *Configuration::Lookup(Item *Head,const char *S,
       return 0;
    
    I = new Item;
-   I->Tag = string(S,Len);
+   I->Tag.assign(S,Len);
    I->Next = *Last;
    I->Parent = Head;
    *Last = I;
@@ -161,7 +161,7 @@ string Configuration::Find(const char *Name,const char *Default) const
    if (Itm == 0 || Itm->Value.empty() == true)
    {
       if (Default == 0)
-	 return string();
+	 return "";
       else
 	 return Default;
    }
@@ -180,7 +180,7 @@ string Configuration::FindFile(const char *Name,const char *Default) const
    if (Itm == 0 || Itm->Value.empty() == true)
    {
       if (Default == 0)
-	 return string();
+	 return "";
       else
 	 return Default;
    }
@@ -294,7 +294,7 @@ string Configuration::FindAny(const char *Name,const char *Default) const
 // Configuration::CndSet - Conditinal Set a value			/*{{{*/
 // ---------------------------------------------------------------------
 /* This will not overwrite */
-void Configuration::CndSet(const char *Name,string Value)
+void Configuration::CndSet(const char *Name,const string &Value)
 {
    Item *Itm = Lookup(Name,true);
    if (Itm == 0)
@@ -306,7 +306,7 @@ void Configuration::CndSet(const char *Name,string Value)
 // Configuration::Set - Set a value					/*{{{*/
 // ---------------------------------------------------------------------
 /* */
-void Configuration::Set(const char *Name,string Value)
+void Configuration::Set(const char *Name,const string &Value)
 {
    Item *Itm = Lookup(Name,true);
    if (Itm == 0)
@@ -330,7 +330,7 @@ void Configuration::Set(const char *Name,int Value)
 // Configuration::Clear - Clear an single value from a list	        /*{{{*/
 // ---------------------------------------------------------------------
 /* */
-void Configuration::Clear(string Name, int Value)
+void Configuration::Clear(const string Name, int Value)
 {
    char S[300];
    snprintf(S,sizeof(S),"%i",Value);
@@ -340,7 +340,7 @@ void Configuration::Clear(string Name, int Value)
 // Configuration::Clear - Clear an single value from a list	        /*{{{*/
 // ---------------------------------------------------------------------
 /* */
-void Configuration::Clear(string Name, string Value)
+void Configuration::Clear(const string Name, string Value)
 {
    Item *Top = Lookup(Name.c_str(),false);
    if (Top == 0 || Top->Child == 0)
@@ -377,7 +377,7 @@ void Configuration::Clear(string Name)
    if (Top == 0) 
       return;
 
-   Top->Value = string();
+   Top->Value.clear();
    Item *Stop = Top;
    Top = Top->Child;
    Stop->Child = 0;
@@ -485,7 +485,7 @@ string Configuration::Item::FullTag(const Item *Stop) const
    sections like 'zone "foo.org" { .. };' This causes each section to be
    added in with a tag like "zone::foo.org" instead of being split 
    tag/value. AsSectional enables Sectional parsing.*/
-bool ReadConfigFile(Configuration &Conf,string FName,bool AsSectional,
+bool ReadConfigFile(Configuration &Conf,const string &FName,bool AsSectional,
 		    unsigned Depth)
 {   
    // Open the stream for reading
@@ -711,13 +711,13 @@ bool ReadConfigFile(Configuration &Conf,string FName,bool AsSectional,
 	    }
 	    
 	    // Empty the buffer
-	    LineBuffer = string();
+	    LineBuffer.clear();
 	    
 	    // Move up a tag, but only if there is no bit to parse
 	    if (TermChar == '}')
 	    {
 	       if (StackPos == 0)
-		  ParentTag = string();
+		  ParentTag.clear();
 	       else
 		  ParentTag = Stack[--StackPos];
 	    }
@@ -742,8 +742,8 @@ bool ReadConfigFile(Configuration &Conf,string FName,bool AsSectional,
 // ReadConfigDir - Read a directory of config files			/*{{{*/
 // ---------------------------------------------------------------------
 /* */
-bool ReadConfigDir(Configuration &Conf,string Dir,bool AsSectional,
-		    unsigned Depth)
+bool ReadConfigDir(Configuration &Conf,const string &Dir,bool AsSectional,
+		   unsigned Depth)
 {   
    DIR *D = opendir(Dir.c_str());
    if (D == 0)
diff --git a/apt-pkg/contrib/configuration.h b/apt-pkg/contrib/configuration.h
index 789bc82cf..0d4078dab 100644
--- a/apt-pkg/contrib/configuration.h
+++ b/apt-pkg/contrib/configuration.h
@@ -69,30 +69,30 @@ class Configuration
    public:
 
    string Find(const char *Name,const char *Default = 0) const;
-   string Find(string Name,const char *Default = 0) const {return Find(Name.c_str(),Default);};
+   string Find(const string Name,const char *Default = 0) const {return Find(Name.c_str(),Default);};
    string FindFile(const char *Name,const char *Default = 0) const;
    string FindDir(const char *Name,const char *Default = 0) const;
    int FindI(const char *Name,int Default = 0) const;
-   int FindI(string Name,int Default = 0) const {return FindI(Name.c_str(),Default);};
+   int FindI(const string Name,int Default = 0) const {return FindI(Name.c_str(),Default);};
    bool FindB(const char *Name,bool Default = false) const;
-   bool FindB(string Name,bool Default = false) const {return FindB(Name.c_str(),Default);};
+   bool FindB(const string Name,bool Default = false) const {return FindB(Name.c_str(),Default);};
    string FindAny(const char *Name,const char *Default = 0) const;
 	      
-   inline void Set(string Name,string Value) {Set(Name.c_str(),Value);};
-   void CndSet(const char *Name,string Value);
-   void Set(const char *Name,string Value);
+   inline void Set(const string Name,string Value) {Set(Name.c_str(),Value);};
+   void CndSet(const char *Name,const string &Value);
+   void Set(const char *Name,const string &Value);
    void Set(const char *Name,int Value);   
    
-   inline bool Exists(string Name) const {return Exists(Name.c_str());};
+   inline bool Exists(const string Name) const {return Exists(Name.c_str());};
    bool Exists(const char *Name) const;
    bool ExistsAny(const char *Name) const;
 
    // clear a whole tree
-   void Clear(string Name);
+   void Clear(const string Name);
 
    // remove a certain value from a list (e.g. the list of "APT::Keep-Fds")
-   void Clear(string List, string Value);
-   void Clear(string List, int Value);
+   void Clear(const string List, string Value);
+   void Clear(const string List, int Value);
 
    inline const Item *Tree(const char *Name) const {return Lookup(Name);};
 
@@ -106,10 +106,12 @@ class Configuration
 
 extern Configuration *_config;
 
-bool ReadConfigFile(Configuration &Conf,string FName,bool AsSectional = false,
+bool ReadConfigFile(Configuration &Conf,const string &FName,
+		    bool AsSectional = false,
 		    unsigned Depth = 0);
 
-bool ReadConfigDir(Configuration &Conf,string Dir,bool AsSectional = false,
-		    unsigned Depth = 0);
+bool ReadConfigDir(Configuration &Conf,const string &Dir,
+		   bool AsSectional = false,
+		   unsigned Depth = 0);
 
 #endif
diff --git a/apt-pkg/contrib/mmap.h b/apt-pkg/contrib/mmap.h
index caffa0f90..e329b167a 100644
--- a/apt-pkg/contrib/mmap.h
+++ b/apt-pkg/contrib/mmap.h
@@ -94,7 +94,7 @@ class DynamicMMap : public MMap
    unsigned long RawAllocate(unsigned long Size,unsigned long Aln = 0);
    unsigned long Allocate(unsigned long ItemSize);
    unsigned long WriteString(const char *String,unsigned long Len = (unsigned long)-1);
-   inline unsigned long WriteString(string S) {return WriteString(S.c_str(),S.length());};
+   inline unsigned long WriteString(const string &S) {return WriteString(S.c_str(),S.length());};
    void UsePools(Pool &P,unsigned int Count) {Pools = &P; PoolCount = Count;};
    
    DynamicMMap(FileFd &F,unsigned long Flags,unsigned long WorkSpace = 2*1024*1024);
diff --git a/apt-pkg/contrib/progress.cc b/apt-pkg/contrib/progress.cc
index 8eb36fc20..cb272e389 100644
--- a/apt-pkg/contrib/progress.cc
+++ b/apt-pkg/contrib/progress.cc
@@ -50,7 +50,7 @@ void OpProgress::Progress(unsigned long Cur)
 // ---------------------------------------------------------------------
 /* */
 void OpProgress::OverallProgress(unsigned long Current, unsigned long Total,
-	  			 unsigned long Size,string Op)
+	  			 unsigned long Size,const string &Op)
 {
    this->Current = Current;
    this->Total = Total;
@@ -67,7 +67,7 @@ void OpProgress::OverallProgress(unsigned long Current, unsigned long Total,
 // OpProgress::SubProgress - Set the sub progress state			/*{{{*/
 // ---------------------------------------------------------------------
 /* */
-void OpProgress::SubProgress(unsigned long SubTotal,string Op)
+void OpProgress::SubProgress(unsigned long SubTotal,const string &Op)
 {
    this->SubTotal = SubTotal;
    SubOp = Op;
diff --git a/apt-pkg/contrib/progress.h b/apt-pkg/contrib/progress.h
index d0b1f5f94..20caf4cdf 100644
--- a/apt-pkg/contrib/progress.h
+++ b/apt-pkg/contrib/progress.h
@@ -59,9 +59,9 @@ class OpProgress
    
    void Progress(unsigned long Current);
    void SubProgress(unsigned long SubTotal);
-   void SubProgress(unsigned long SubTotal,string Op);
+   void SubProgress(unsigned long SubTotal,const string &Op);
    void OverallProgress(unsigned long Current,unsigned long Total,
-			unsigned long Size,string Op);
+			unsigned long Size,const string &Op);
    virtual void Done() {};
    
    OpProgress();
diff --git a/apt-pkg/contrib/strutl.cc b/apt-pkg/contrib/strutl.cc
index a75fbdf92..d96155917 100644
--- a/apt-pkg/contrib/strutl.cc
+++ b/apt-pkg/contrib/strutl.cc
@@ -199,10 +199,10 @@ bool ParseCWord(const char *&String,string &Res)
 // QuoteString - Convert a string into quoted from			/*{{{*/
 // ---------------------------------------------------------------------
 /* */
-string QuoteString(string Str,const char *Bad)
+string QuoteString(const string &Str, const char *Bad)
 {
    string Res;
-   for (string::iterator I = Str.begin(); I != Str.end(); I++)
+   for (string::const_iterator I = Str.begin(); I != Str.end(); I++)
    {
       if (strchr(Bad,*I) != 0 || isprint(*I) == 0 || 
 	  *I <= 0x20 || *I >= 0x7F)
@@ -220,7 +220,7 @@ string QuoteString(string Str,const char *Bad)
 // DeQuoteString - Convert a string from quoted from                    /*{{{*/
 // ---------------------------------------------------------------------
 /* This undoes QuoteString */
-string DeQuoteString(string Str)
+string DeQuoteString(const string &Str)
 {
    string Res;
    for (string::const_iterator I = Str.begin(); I != Str.end(); I++)
@@ -317,7 +317,7 @@ string TimeToStr(unsigned long Sec)
 // SubstVar - Substitute a string for another string			/*{{{*/
 // ---------------------------------------------------------------------
 /* This replaces all occurances of Subst with Contents in Str. */
-string SubstVar(string Str,string Subst,string Contents)
+string SubstVar(const string &Str,const string &Subst,const string &Contents)
 {
    string::size_type Pos = 0;
    string::size_type OldPos = 0;
@@ -348,21 +348,18 @@ string SubstVar(string Str,const struct SubstVar *Vars)
 /* This converts a URI into a safe filename. It quotes all unsafe characters
    and converts / to _ and removes the scheme identifier. The resulting
    file name should be unique and never occur again for a different file */
-string URItoFileName(string URI)
+string URItoFileName(const string &URI)
 {
    // Nuke 'sensitive' items
    ::URI U(URI);
-   U.User = string();
-   U.Password = string();
-   U.Access = "";
+   U.User.clear();
+   U.Password.clear();
+   U.Access.clear();
    
    // "\x00-\x20{}|\\\\^\\[\\]<>\"\x7F-\xFF";
-   URI = QuoteString(U,"\\|{}[]<>\"^~_=!@#$%^&*");
-   string::iterator J = URI.begin();
-   for (; J != URI.end(); J++)
-      if (*J == '/') 
-	 *J = '_';
-   return URI;
+   string NewURI = QuoteString(U,"\\|{}[]<>\"^~_=!@#$%^&*");
+   replace(NewURI.begin(),NewURI.end(),'/','_');
+   return NewURI;
 }
 									/*}}}*/
 // Base64Encode - Base64 Encoding routine for short strings		/*{{{*/
@@ -371,7 +368,7 @@ string URItoFileName(string URI)
    from wget and then patched and bug fixed.
  
    This spec can be found in rfc2045 */
-string Base64Encode(string S)
+string Base64Encode(const string &S)
 {
    // Conversion table.
    static char tbl[64] = {'A','B','C','D','E','F','G','H',
@@ -540,17 +537,17 @@ int stringcasecmp(string::const_iterator A,string::const_iterator AEnd,
 // ---------------------------------------------------------------------
 /* The format is like those used in package files and the method 
    communication system */
-string LookupTag(string Message,const char *Tag,const char *Default)
+string LookupTag(const string &Message,const char *Tag,const char *Default)
 {
    // Look for a matching tag.
    int Length = strlen(Tag);
-   for (string::iterator I = Message.begin(); I + Length < Message.end(); I++)
+   for (string::const_iterator I = Message.begin(); I + Length < Message.end(); I++)
    {
       // Found the tag
       if (I[Length] == ':' && stringcasecmp(I,I+Length,Tag) == 0)
       {
 	 // Find the end of line and strip the leading/trailing spaces
-	 string::iterator J;
+	 string::const_iterator J;
 	 I += Length + 1;
 	 for (; isspace(*I) != 0 && I < Message.end(); I++);
 	 for (J = I; *J != '\n' && J < Message.end(); J++);
@@ -572,7 +569,7 @@ string LookupTag(string Message,const char *Tag,const char *Default)
 // ---------------------------------------------------------------------
 /* This inspects the string to see if it is true or if it is false and
    then returns the result. Several varients on true/false are checked. */
-int StringToBool(string Text,int Default)
+int StringToBool(const string &Text,int Default)
 {
    char *End;
    int Res = strtol(Text.c_str(),&End,0);   
@@ -738,7 +735,7 @@ static time_t timegm(struct tm *t)
    'timegm' to convert a struct tm in UTC to a time_t. For some bizzar
    reason the C library does not provide any such function :< This also
    handles the weird, but unambiguous FTP time format*/
-bool StrToTime(string Val,time_t &Result)
+bool StrToTime(const string &Val,time_t &Result)
 {
    struct tm Tm;
    char Month[10];
@@ -825,7 +822,7 @@ static int HexDigit(int c)
 // Hex2Num - Convert a long hex number into a buffer			/*{{{*/
 // ---------------------------------------------------------------------
 /* The length of the buffer must be exactly 1/2 the length of the string. */
-bool Hex2Num(string Str,unsigned char *Num,unsigned int Length)
+bool Hex2Num(const string &Str,unsigned char *Num,unsigned int Length)
 {
    if (Str.length() != Length*2)
       return false;
@@ -986,7 +983,7 @@ char *safe_snprintf(char *Buffer,char *End,const char *Format,...)
 // ---------------------------------------------------------------------
 /* The domain list is a comma seperate list of domains that are suffix
    matched against the argument */
-bool CheckDomainList(string Host,string List)
+bool CheckDomainList(const string &Host,const string &List)
 {
    string::const_iterator Start = List.begin();
    for (string::const_iterator Cur = List.begin(); Cur <= List.end(); Cur++)
@@ -1009,7 +1006,7 @@ bool CheckDomainList(string Host,string List)
 // URI::CopyFrom - Copy from an object					/*{{{*/
 // ---------------------------------------------------------------------
 /* This parses the URI into all of its components */
-void URI::CopyFrom(string U)
+void URI::CopyFrom(const string &U)
 {
    string::const_iterator I = U.begin();
 
@@ -1038,9 +1035,9 @@ void URI::CopyFrom(string U)
       SingleSlash = U.end();
 
    // We can now write the access and path specifiers
-   Access = string(U,0,FirstColon - U.begin());
+   Access.assign(U.begin(),FirstColon);
    if (SingleSlash != U.end())
-      Path = string(U,SingleSlash - U.begin());
+      Path.assign(SingleSlash,U.end());
    if (Path.empty() == true)
       Path = "/";
 
@@ -1070,14 +1067,14 @@ void URI::CopyFrom(string U)
    if (At == SingleSlash)
    {
       if (FirstColon < SingleSlash)
-	 Host = string(U,FirstColon - U.begin(),SingleSlash - FirstColon);
+	 Host.assign(FirstColon,SingleSlash);
    }
    else
    {
-      Host = string(U,At - U.begin() + 1,SingleSlash - At - 1);
-      User = string(U,FirstColon - U.begin(),SecondColon - FirstColon);
+      Host.assign(At+1,SingleSlash);
+      User.assign(FirstColon,SecondColon);
       if (SecondColon < At)
-	 Password = string(U,SecondColon - U.begin() + 1,At - SecondColon - 1);
+	 Password.assign(SecondColon+1,At);
    }   
    
    // Now we parse the RFC 2732 [] hostnames.
@@ -1105,7 +1102,7 @@ void URI::CopyFrom(string U)
    // Tsk, weird.
    if (InBracket == true)
    {
-      Host = string();
+      Host.clear();
       return;
    }
    
@@ -1116,7 +1113,7 @@ void URI::CopyFrom(string U)
       return;
    
    Port = atoi(string(Host,Pos+1).c_str());
-   Host = string(Host,0,Pos);
+   Host.assign(Host,0,Pos);
 }
 									/*}}}*/
 // URI::operator string - Convert the URI to a string			/*{{{*/
@@ -1171,12 +1168,12 @@ URI::operator string()
 // URI::SiteOnly - Return the schema and site for the URI		/*{{{*/
 // ---------------------------------------------------------------------
 /* */
-string URI::SiteOnly(string URI)
+string URI::SiteOnly(const string &URI)
 {
    ::URI U(URI);
-   U.User = string();
-   U.Password = string();
-   U.Path = string();
+   U.User.clear();
+   U.Password.clear();
+   U.Path.clear();
    U.Port = 0;
    return U;
 }
diff --git a/apt-pkg/contrib/strutl.h b/apt-pkg/contrib/strutl.h
index 353e78ac9..6ec2b7811 100644
--- a/apt-pkg/contrib/strutl.h
+++ b/apt-pkg/contrib/strutl.h
@@ -43,24 +43,24 @@ char *_strstrip(char *String);
 char *_strtabexpand(char *String,size_t Len);
 bool ParseQuoteWord(const char *&String,string &Res);
 bool ParseCWord(const char *&String,string &Res);
-string QuoteString(string Str,const char *Bad);
-string DeQuoteString(string Str);
+string QuoteString(const string &Str,const char *Bad);
+string DeQuoteString(const string &Str);
 string SizeToStr(double Bytes);
 string TimeToStr(unsigned long Sec);
-string Base64Encode(string Str);
-string URItoFileName(string URI);
+string Base64Encode(const string &Str);
+string URItoFileName(const string &URI);
 string TimeRFC1123(time_t Date);
-bool StrToTime(string Val,time_t &Result);
-string LookupTag(string Message,const char *Tag,const char *Default = 0);
-int StringToBool(string Text,int Default = -1);
+bool StrToTime(const string &Val,time_t &Result);
+string LookupTag(const string &Message,const char *Tag,const char *Default = 0);
+int StringToBool(const string &Text,int Default = -1);
 bool ReadMessages(int Fd, vector<string> &List);
 bool StrToNum(const char *Str,unsigned long &Res,unsigned Len,unsigned Base = 0);
-bool Hex2Num(string Str,unsigned char *Num,unsigned int Length);
+bool Hex2Num(const string &Str,unsigned char *Num,unsigned int Length);
 bool TokSplitString(char Tok,char *Input,char **List,
 		    unsigned long ListMax);
 void ioprintf(ostream &out,const char *format,...) APT_FORMAT2;
 char *safe_snprintf(char *Buffer,char *End,const char *Format,...) APT_FORMAT3;
-bool CheckDomainList(string Host,string List);
+bool CheckDomainList(const string &Host, const string &List);
 
 #define APT_MKSTRCMP(name,func) \
 inline int name(const char *A,const char *AEnd,const char *B) {return func(A,AEnd,B,B+strlen(B));}; \
@@ -101,7 +101,7 @@ inline const char *DeNull(const char *s) {return (s == 0?"(null)":s);};
 
 class URI
 {
-   void CopyFrom(string From);
+   void CopyFrom(const string &From);
 		 
    public:
    
@@ -113,9 +113,9 @@ class URI
    unsigned int Port;
    
    operator string();
-   inline void operator =(string From) {CopyFrom(From);};
+   inline void operator =(const string &From) {CopyFrom(From);};
    inline bool empty() {return Access.empty();};
-   static string SiteOnly(string URI);
+   static string SiteOnly(const string &URI);
    
    URI(string Path) {CopyFrom(Path);};
    URI() : Port(0) {};
@@ -127,7 +127,7 @@ struct SubstVar
    const string *Contents;
 };
 string SubstVar(string Str,const struct SubstVar *Vars);
-string SubstVar(string Str,string Subst,string Contents);
+string SubstVar(const string &Str,const string &Subst,const string &Contents);
 
 struct RxChoiceList
 {
diff --git a/apt-pkg/deb/deblistparser.cc b/apt-pkg/deb/deblistparser.cc
index 25b533773..b11d2531c 100644
--- a/apt-pkg/deb/deblistparser.cc
+++ b/apt-pkg/deb/deblistparser.cc
@@ -377,12 +377,12 @@ const char *debListParser::ParseDepends(const char *Start,const char *Stop,
       const char *End = I;
       for (; End > Start && isspace(End[-1]); End--);
       
-      Ver = string(Start,End-Start);
+      Ver.assign(Start,End-Start);
       I++;
    }
    else
    {
-      Ver = string();
+      Ver.clear();
       Op = pkgCache::Dep::NoOp;
    }
    
diff --git a/apt-pkg/pkgcache.cc b/apt-pkg/pkgcache.cc
index 6ef7cafb0..9926befe9 100644
--- a/apt-pkg/pkgcache.cc
+++ b/apt-pkg/pkgcache.cc
@@ -153,7 +153,7 @@ bool pkgCache::ReMap()
 /* This is used to generate the hash entries for the HashTable. With my
    package list from bo this function gets 94% table usage on a 512 item
    table (480 used items) */
-unsigned long pkgCache::sHash(string Str) const
+unsigned long pkgCache::sHash(const string &Str) const
 {
    unsigned long Hash = 0;
    for (string::const_iterator I = Str.begin(); I != Str.end(); I++)
@@ -173,7 +173,7 @@ unsigned long pkgCache::sHash(const char *Str) const
 // Cache::FindPkg - Locate a package by name				/*{{{*/
 // ---------------------------------------------------------------------
 /* Returns 0 on error, pointer to the package otherwise */
-pkgCache::PkgIterator pkgCache::FindPkg(string Name)
+pkgCache::PkgIterator pkgCache::FindPkg(const string &Name)
 {
    // Look at the hash bucket
    Package *Pkg = PkgP + HeaderP->HashTable[Hash(Name)];
diff --git a/apt-pkg/pkgcache.h b/apt-pkg/pkgcache.h
index b07951dfb..587d97534 100644
--- a/apt-pkg/pkgcache.h
+++ b/apt-pkg/pkgcache.h
@@ -89,7 +89,7 @@ class pkgCache
    string CacheFile;
    MMap &Map;
 
-   unsigned long sHash(string S) const;
+   unsigned long sHash(const string &S) const;
    unsigned long sHash(const char *S) const;
    
    public:
@@ -111,14 +111,14 @@ class pkgCache
    inline void *DataEnd() {return ((unsigned char *)Map.Data()) + Map.Size();};
       
    // String hashing function (512 range)
-   inline unsigned long Hash(string S) const {return sHash(S);};
+   inline unsigned long Hash(const string &S) const {return sHash(S);};
    inline unsigned long Hash(const char *S) const {return sHash(S);};
 
    // Usefull transformation things
    const char *Priority(unsigned char Priority);
    
    // Accessors
-   PkgIterator FindPkg(string Name);
+   PkgIterator FindPkg(const string &Name);
    Header &Head() {return *HeaderP;};
    inline PkgIterator PkgBegin();
    inline PkgIterator PkgEnd();
diff --git a/apt-pkg/pkgcachegen.cc b/apt-pkg/pkgcachegen.cc
index 2340f97fd..de854bee5 100644
--- a/apt-pkg/pkgcachegen.cc
+++ b/apt-pkg/pkgcachegen.cc
@@ -266,7 +266,7 @@ bool pkgCacheGenerator::MergeFileProvides(ListParser &List)
 // CacheGenerator::NewPackage - Add a new package			/*{{{*/
 // ---------------------------------------------------------------------
 /* This creates a new package structure and adds it to the hash table */
-bool pkgCacheGenerator::NewPackage(pkgCache::PkgIterator &Pkg,string Name)
+bool pkgCacheGenerator::NewPackage(pkgCache::PkgIterator &Pkg,const string &Name)
 {
    Pkg = Cache.FindPkg(Name);
    if (Pkg.end() == false)
@@ -330,7 +330,7 @@ bool pkgCacheGenerator::NewFileVer(pkgCache::VerIterator &Ver,
 // ---------------------------------------------------------------------
 /* This puts a version structure in the linked list */
 unsigned long pkgCacheGenerator::NewVersion(pkgCache::VerIterator &Ver,
-					    string VerStr,
+					    const string &VerStr,
 					    unsigned long Next)
 {
    // Get a structure
@@ -354,8 +354,8 @@ unsigned long pkgCacheGenerator::NewVersion(pkgCache::VerIterator &Ver,
 /* This creates a dependency element in the tree. It is linked to the
    version and to the package that it is pointing to. */
 bool pkgCacheGenerator::ListParser::NewDepends(pkgCache::VerIterator Ver,
-					       string PackageName,
-					       string Version,
+					       const string &PackageName,
+					       const string &Version,
 					       unsigned int Op,
 					       unsigned int Type)
 {
@@ -419,8 +419,8 @@ bool pkgCacheGenerator::ListParser::NewDepends(pkgCache::VerIterator Ver,
 // ---------------------------------------------------------------------
 /* */
 bool pkgCacheGenerator::ListParser::NewProvides(pkgCache::VerIterator Ver,
-					        string PackageName,
-						string Version)
+					        const string &PackageName,
+						const string &Version)
 {
    pkgCache &Cache = Owner->Cache;
 
@@ -459,7 +459,7 @@ bool pkgCacheGenerator::ListParser::NewProvides(pkgCache::VerIterator Ver,
 // ---------------------------------------------------------------------
 /* This is used to select which file is to be associated with all newly
    added versions. The caller is responsible for setting the IMS fields. */
-bool pkgCacheGenerator::SelectFile(string File,string Site,
+bool pkgCacheGenerator::SelectFile(const string &File,const string &Site,
 				   const pkgIndexFile &Index,
 				   unsigned long Flags)
 {
@@ -543,7 +543,7 @@ unsigned long pkgCacheGenerator::WriteUniqString(const char *S,
 /* This just verifies that each file in the list of index files exists,
    has matching attributes with the cache and the cache does not have
    any extra files. */
-static bool CheckValidity(string CacheFile, FileIterator Start, 
+static bool CheckValidity(const string &CacheFile, FileIterator Start, 
                           FileIterator End,MMap **OutMap = 0)
 {
    // No file, certainly invalid
diff --git a/apt-pkg/pkgcachegen.h b/apt-pkg/pkgcachegen.h
index 7d0920629..9a729eea4 100644
--- a/apt-pkg/pkgcachegen.h
+++ b/apt-pkg/pkgcachegen.h
@@ -53,17 +53,17 @@ class pkgCacheGenerator
    // Flag file dependencies
    bool FoundFileDeps;
    
-   bool NewPackage(pkgCache::PkgIterator &Pkg,string Pkg);
+   bool NewPackage(pkgCache::PkgIterator &Pkg,const string &Pkg);
    bool NewFileVer(pkgCache::VerIterator &Ver,ListParser &List);
-   unsigned long NewVersion(pkgCache::VerIterator &Ver,string VerStr,unsigned long Next);
+   unsigned long NewVersion(pkgCache::VerIterator &Ver,const string &VerStr,unsigned long Next);
 
    public:
 
    unsigned long WriteUniqString(const char *S,unsigned int Size);
-   inline unsigned long WriteUniqString(string S) {return WriteUniqString(S.c_str(),S.length());};
+   inline unsigned long WriteUniqString(const string &S) {return WriteUniqString(S.c_str(),S.length());};
 
    void DropProgress() {Progress = 0;};
-   bool SelectFile(string File,string Site,pkgIndexFile const &Index,
+   bool SelectFile(const string &File,const string &Site,pkgIndexFile const &Index,
 		   unsigned long Flags = 0);
    bool MergeList(ListParser &List,pkgCache::VerIterator *Ver = 0);
    inline pkgCache &GetCache() {return Cache;};
@@ -94,12 +94,13 @@ class pkgCacheGenerator::ListParser
 
    inline unsigned long WriteUniqString(string S) {return Owner->WriteUniqString(S);};
    inline unsigned long WriteUniqString(const char *S,unsigned int Size) {return Owner->WriteUniqString(S,Size);};
-   inline unsigned long WriteString(string S) {return Owner->Map.WriteString(S);};
+   inline unsigned long WriteString(const string &S) {return Owner->Map.WriteString(S);};
    inline unsigned long WriteString(const char *S,unsigned int Size) {return Owner->Map.WriteString(S,Size);};
-   bool NewDepends(pkgCache::VerIterator Ver,string Package,
-		   string Version,unsigned int Op,
+   bool NewDepends(pkgCache::VerIterator Ver,const string &Package,
+		   const string &Version,unsigned int Op,
 		   unsigned int Type);
-   bool NewProvides(pkgCache::VerIterator Ver,string Package,string Version);
+   bool NewProvides(pkgCache::VerIterator Ver,const string &Package,
+		    const string &Version);
    
    public: