/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef _CONFTREE_H_
#define _CONFTREE_H_
/**
* A simple configuration file implementation.
*
* Configuration files have lines like 'name = value', and/or like '[subkey]'
*
* Lines like '[subkey]' in the file define subsections, with independant
* configuration namespaces. Only subsections holding at least one variable are
* significant (empty subsections may be deleted during an update, or not)
*
* Whitespace around name and value is insignificant.
*
* The names are case-sensitive but don't depend on it, this might change
*
* Values can be queried for, or set.
*
* Any line without a '=' is a comment (a line like #var = value
* actually assigns a variable named '#var', which is not a big issue)
*
* A configuration object can be created empty or by reading from a file or
* a string.
* All 'set' calls cause an immediate rewrite of the backing object if any
* (file or string)
*
* The ConfTree derived class interprets the subkeys as file paths and
* lets subdir keys hierarchically inherit the properties from
* parents.
*
* The ConfStack class stacks several Con(Simple/Tree) objects so that
* parameters from the top of the stack override the values from lower
* (useful to have central/personal config files)
*/
#include <string>
#include <map>
#include <list>
// rh7.3 likes iostream better...
#if defined(__GNUC__) && __GNUC__ < 3
#include <iostream>
#else
#include <istream>
#include <ostream>
#endif
#ifndef NO_NAMESPACES
using std::string;
using std::list;
using std::map;
using std::istream;
using std::ostream;
#endif // NO_NAMESPACES
#include "pathut.h"
/** Internal class used for storing presentation information */
class ConfLine {
public:
enum Kind {CFL_COMMENT, CFL_SK, CFL_VAR};
Kind m_kind;
string m_data;
ConfLine(Kind k, const string& d)
: m_kind(k), m_data(d)
{
}
bool operator==(const ConfLine& o)
{
return o.m_kind == m_kind && o.m_data == m_data;
}
};
/**
* Virtual base class used to define an interface mostly useful for testing
*/
class ConfNull {
public:
enum StatusCode {STATUS_ERROR=0, STATUS_RO=1, STATUS_RW=2};
virtual ~ConfNull() {};
virtual int get(const string &name, string &value,
const string &sk = "") = 0;
virtual int set(const string &nm, const string &val,
const string &sk = "") = 0;
virtual bool ok() = 0;
virtual list<string> getNames(const string &sk) = 0;
virtual int erase(const string &, const string &) = 0;
virtual int eraseKey(const string &) = 0;
virtual void listall() {};
virtual list<string> getSubKeys() = 0;
virtual bool holdWrites(bool) = 0;
};
/**
* Manages a simple configuration file with subsections.
*/
class ConfSimple : public ConfNull {
public:
/**
* Build the object by reading content from file.
* @param filename file to open
* @param readonly if true open readonly, else rw
* @param tildexp try tilde (home dir) expansion for subkey values
*/
ConfSimple(const char *fname, int readonly = 0, bool tildexp = false);
/**
* Build the object by reading content from a string
* @param data points to the data to parse.
* @param readonly if true open readonly, else rw
* @param tildexp try tilde (home dir) expansion for subsection names
*/
ConfSimple(string *data, int readonly = 0, bool tildexp = false);
/**
* Build an empty object. This will be memory only, with no backing store.
* @param readonly if true open read only, else rw
* @param tildexp try tilde (home dir) expansion for subsection names
*/
ConfSimple(int readonly = 0, bool tildexp = false);
virtual ~ConfSimple() {};
/**
* Decide if we actually rewrite the backing-store after modifying the
* tree.
*/
virtual bool holdWrites(bool on)
{
m_holdWrites = on;
if (on == false) {
return write();
} else
return true;
}
/**
* Get value for named parameter, from specified subsection (looks in
* global space if sk is empty).
* @return 0 if name not found, 1 else
*/
virtual int get(const string &name, string &value, const string &sk = "");
/**
* Set value for named parameter in specified subsection (or global)
* @return 0 for error, 1 else
*/
virtual int set(const string &nm, const string &val, const string &sk = "");
/**
* Remove name and value from config
*/
virtual int erase(const string &name, const string &sk);
/**
* Erase all names under given subkey (and subkey itself)
*/
virtual int eraseKey(const string &sk);
virtual StatusCode getStatus();
virtual bool ok() {return getStatus() != STATUS_ERROR;}
/**
* Walk the configuration values, calling function for each.
* The function is called with a null nm when changing subsections (the
* value is then the new subsection name)
* @return WALK_STOP when/if the callback returns WALK_STOP,
* WALK_CONTINUE else (got to end of config)
*/
enum WalkerCode {WALK_STOP, WALK_CONTINUE};
virtual WalkerCode sortwalk(WalkerCode
(*wlkr)(void *cldata, const string &nm,
const string &val),
void *clidata);
/** List all values to stdout */
virtual void listall();
/**
* Return all names in given submap
*/
virtual list<string> getNames(const string &sk);
/**
* Return all subkeys
*/
virtual list<string> getSubKeys();
virtual string getFilename() {return m_filename;}
/**
* Copy constructor. Expensive but less so than a full rebuild
*/
ConfSimple(const ConfSimple &rhs)
: ConfNull(), m_data(0)
{
if ((status = rhs.status) == STATUS_ERROR)
return;
m_filename = rhs.m_filename;
// Note: we just share the pointer, this doesnt belong to us
m_data = rhs.m_data;
m_submaps = rhs.m_submaps;
}
/**
* Assignement. This is expensive
*/
ConfSimple& operator=(const ConfSimple &rhs)
{
if (this != &rhs && (status = rhs.status) != STATUS_ERROR) {
m_filename = rhs.m_filename;
// Note: we don't own data. Just share the pointer
m_data = rhs.m_data;
m_submaps = rhs.m_submaps;
}
return *this;
}
protected:
bool dotildexpand;
StatusCode status;
private:
// Set if we're working with a file
string m_filename;
// Set if we're working with an in-memory string
string *m_data;
// Configuration data submaps (one per subkey, the main data has a
// null subkey)
map<string, map<string, string> > m_submaps;
// Presentation data. We keep the comments, empty lines and
// variable and subkey ordering information in there (for
// rewriting the file while keeping hand-edited information)
list<ConfLine> m_order;
// Control if we're writing to the backing store
bool m_holdWrites;
void parseinput(istream& input);
bool write();
bool write(ostream& out);
// Internal version of set: no RW checking
virtual int i_set(const string &nm, const string &val,
const string &sk, bool init = false);
};
/**
* This is a configuration class which attaches tree-like signification to the
* submap names.
*
* If a given variable is not found in the specified section, it will be
* looked up the tree of section names, and in the global space.
*
* submap names should be '/' separated paths (ie: /sub1/sub2). No checking
* is done, but else the class adds no functionality to ConfSimple.
*
* NOTE: contrary to common behaviour, the global or root space is NOT
* designated by '/' but by '' (empty subkey). A '/' subkey will not
* be searched at all.
*/
class ConfTree : public ConfSimple {
public:
/* The constructors just call ConfSimple's, asking for key tilde
* expansion */
ConfTree(const char *fname, int readonly = 0)
: ConfSimple(fname, readonly, true) {}
ConfTree(string *data, int readonly = 0)
: ConfSimple(data, readonly, true) {}
ConfTree(int readonly = 0)
: ConfSimple(readonly, true) {}
virtual ~ConfTree() {};
ConfTree(const ConfTree& r) : ConfSimple(r) {};
ConfTree& operator=(const ConfTree& r) {
ConfSimple::operator=(r);
return *this;
}
/**
* Get value for named parameter, from specified subsection, or its
* parents.
* @return 0 if name not found, 1 else
*/
virtual int get(const string &name, string &value, const string &sk);
};
/**
* Use several config files, trying to get values from each in order. Used to
* have a central config, with possible overrides from more specific
* (ie personal) ones.
*
* Notes: it's ok for some of the files in the list to not exist, but the last
* one must or we generate an error. We open all trees readonly, except the
* topmost one if requested. All writes go to the topmost file. Note that
* erase() won't work except for parameters only defined in the topmost
* file (it erases only from there).
*/
template <class T> class ConfStack : public ConfNull {
public:
/// Construct from list of configuration file names. The earler
/// files in have priority when fetching values. Only the first
/// file will be updated if ro is false and set() is used.
ConfStack(const list<string> &fns, bool ro = true)
{
construct(fns, ro);
}
/// Construct out of single file name and list of directories
ConfStack(const string& nm, const list<string>& dirs, bool ro = true)
{
list<string> fns;
for (list<string>::const_iterator it = dirs.begin();
it != dirs.end(); it++){
fns.push_back(path_cat(*it, nm));
}
ConfStack::construct(fns, ro);
}
ConfStack(const ConfStack &rhs)
: ConfNull()
{
init_from(rhs);
}
virtual ~ConfStack()
{
clear();
m_ok = false;
}
ConfStack& operator=(const ConfStack &rhs)
{
if (this != &rhs){
clear();
m_ok = rhs.m_ok;
if (m_ok)
init_from(rhs);
}
return *this;
}
virtual int get(const string &name, string &value, const string &sk)
{
typename list<T*>::iterator it;
for (it = m_confs.begin();it != m_confs.end();it++) {
if ((*it)->get(name, value, sk))
return true;
}
return false;
}
virtual int set(const string &nm, const string &val, const string &sk = "")
{
if (!m_ok)
return 0;
// Avoid adding unneeded entries: if the new value matches the
// one out from the deeper configs, erase or dont add it
// from/to the topmost file
typename list<T*>::iterator it = m_confs.begin();
it++;
while (it != m_confs.end()) {
string value;
if ((*it)->get(nm, value, sk)) {
// This file has value for nm/sk. If it is the same as the new
// one, no need for an entry in the topmost file. Else, stop
// looking and add the new entry
if (value == val) {
m_confs.front()->erase(nm, sk);
return true;
} else {
break;
}
}
it++;
}
return m_confs.front()->set(nm, val, sk);
}
virtual int erase(const string &nm, const string &sk)
{
return m_confs.front()->erase(nm, sk);
}
virtual int eraseKey(const string &sk)
{
return m_confs.front()->eraseKey(sk);
}
virtual bool holdWrites(bool on)
{
return m_confs.front()->holdWrites(on);
}
virtual list<string> getNames(const string &sk)
{
list<string> nms;
typename list<T*>::iterator it;
for (it = m_confs.begin();it != m_confs.end(); it++) {
list<string> lst;
lst = (*it)->getNames(sk);
nms.insert(nms.end(), lst.begin(), lst.end());
}
nms.sort();
nms.unique();
return nms;
}
virtual list<string> getSubKeys()
{
list<string> sks;
typename list<T*>::iterator it;
for (it = m_confs.begin();it != m_confs.end(); it++) {
list<string> lst;
lst = (*it)->getSubKeys();
sks.insert(sks.end(), lst.begin(), lst.end());
}
sks.sort();
sks.unique();
return sks;
}
virtual bool ok() {return m_ok;}
private:
bool m_ok;
list<T*> m_confs;
/// Reset to pristine
void clear() {
typename list<T*>::iterator it;
for (it = m_confs.begin();it != m_confs.end();it++) {
delete (*it);
}
m_confs.clear();
}
/// Common code to initialize from existing object
void init_from(const ConfStack &rhs) {
if ((m_ok = rhs.m_ok)) {
typename list<T*>::const_iterator it;
for (it = rhs.m_confs.begin();it != rhs.m_confs.end();it++) {
m_confs.push_back(new T(**it));
}
}
}
/// Common construct from file list code
void construct(const list<string> &fns, bool ro) {
list<string>::const_iterator it;
bool lastok = false;
for (it = fns.begin(); it != fns.end(); it++) {
T* p = new T(it->c_str(), ro);
if (p && p->ok()) {
m_confs.push_back(p);
lastok = true;
} else {
delete p;
lastok = false;
if (!ro) {
// For rw acccess, the topmost file needs to be ok
// (ro is set to true after the first file)
break;
}
}
ro = true;
}
m_ok = lastok;
}
};
#endif /*_CONFTREE_H_ */