diff -r c35afa9e89e7 -r ef88c0a30f85 lemon/glpk.cc
--- a/lemon/glpk.cc	Mon Jan 12 23:11:39 2009 +0100
+++ b/lemon/glpk.cc	Thu Nov 05 15:48:01 2009 +0100
@@ -2,7 +2,7 @@
  *
  * This file is a part of LEMON, a generic C++ optimization library.
  *
- * Copyright (C) 2003-2008
+ * Copyright (C) 2003-2009
  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
  * (Egervary Research Group on Combinatorial Optimization, EGRES).
  *
@@ -31,6 +31,7 @@
   GlpkBase::GlpkBase() : LpBase() {
     lp = glp_create_prob();
     glp_create_index(lp);
+    messageLevel(MESSAGE_NOTHING);
   }
 
   GlpkBase::GlpkBase(const GlpkBase &other) : LpBase() {
@@ -39,6 +40,7 @@
     glp_create_index(lp);
     rows = other.rows;
     cols = other.cols;
+    messageLevel(MESSAGE_NOTHING);
   }
 
   GlpkBase::~GlpkBase() {
@@ -57,6 +59,42 @@
     return i;
   }
 
+  int GlpkBase::_addRow(Value lo, ExprIterator b, 
+                        ExprIterator e, Value up) {
+    int i = glp_add_rows(lp, 1);
+
+    if (lo == -INF) {
+      if (up == INF) {
+        glp_set_row_bnds(lp, i, GLP_FR, lo, up);
+      } else {
+        glp_set_row_bnds(lp, i, GLP_UP, lo, up);
+      }    
+    } else {
+      if (up == INF) {
+        glp_set_row_bnds(lp, i, GLP_LO, lo, up);
+      } else if (lo != up) {        
+        glp_set_row_bnds(lp, i, GLP_DB, lo, up);
+      } else {
+        glp_set_row_bnds(lp, i, GLP_FX, lo, up);
+      }
+    }
+
+    std::vector<int> indexes;
+    std::vector<Value> values;
+
+    indexes.push_back(0);
+    values.push_back(0);
+
+    for(ExprIterator it = b; it != e; ++it) {
+      indexes.push_back(it->first);
+      values.push_back(it->second);
+    }
+
+    glp_set_mat_row(lp, i, values.size() - 1,
+                    &indexes.front(), &values.front());
+    return i;
+  }
+
   void GlpkBase::_eraseCol(int i) {
     int ca[2];
     ca[1] = i;
@@ -522,20 +560,46 @@
     cols.clear();
   }
 
+  void GlpkBase::freeEnv() {
+    glp_free_env();
+  }
+
+  void GlpkBase::_messageLevel(MessageLevel level) {
+    switch (level) {
+    case MESSAGE_NOTHING:
+      _message_level = GLP_MSG_OFF;
+      break;
+    case MESSAGE_ERROR:
+      _message_level = GLP_MSG_ERR;
+      break;
+    case MESSAGE_WARNING:
+      _message_level = GLP_MSG_ERR;
+      break;
+    case MESSAGE_NORMAL:
+      _message_level = GLP_MSG_ON;
+      break;
+    case MESSAGE_VERBOSE:
+      _message_level = GLP_MSG_ALL;
+      break;
+    }
+  }
+
+  GlpkBase::FreeEnvHelper GlpkBase::freeEnvHelper;
+
   // GlpkLp members
 
   GlpkLp::GlpkLp()
-    : LpBase(), GlpkBase(), LpSolver() {
-    messageLevel(MESSAGE_NO_OUTPUT);
+    : LpBase(), LpSolver(), GlpkBase() {
+    presolver(false);
   }
 
   GlpkLp::GlpkLp(const GlpkLp& other)
-    : LpBase(other), GlpkBase(other), LpSolver(other) {
-    messageLevel(MESSAGE_NO_OUTPUT);
+    : LpBase(other), LpSolver(other), GlpkBase(other) {
+    presolver(false);
   }
 
-  GlpkLp* GlpkLp::_newSolver() const { return new GlpkLp; }
-  GlpkLp* GlpkLp::_cloneSolver() const { return new GlpkLp(*this); }
+  GlpkLp* GlpkLp::newSolver() const { return new GlpkLp; }
+  GlpkLp* GlpkLp::cloneSolver() const { return new GlpkLp(*this); }
 
   const char* GlpkLp::_solverName() const { return "GlpkLp"; }
 
@@ -554,22 +618,26 @@
     glp_smcp smcp;
     glp_init_smcp(&smcp);
 
-    switch (_message_level) {
-    case MESSAGE_NO_OUTPUT:
-      smcp.msg_lev = GLP_MSG_OFF;
+    smcp.msg_lev = _message_level;
+    smcp.presolve = _presolve;
+
+    // If the basis is not valid we get an error return value.
+    // In this case we can try to create a new basis.
+    switch (glp_simplex(lp, &smcp)) {
+    case 0:
       break;
-    case MESSAGE_ERROR_MESSAGE:
-      smcp.msg_lev = GLP_MSG_ERR;
+    case GLP_EBADB:
+    case GLP_ESING:
+    case GLP_ECOND:
+      glp_term_out(false);
+      glp_adv_basis(lp, 0);
+      glp_term_out(true);
+      if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
       break;
-    case MESSAGE_NORMAL_OUTPUT:
-      smcp.msg_lev = GLP_MSG_ON;
-      break;
-    case MESSAGE_FULL_OUTPUT:
-      smcp.msg_lev = GLP_MSG_ALL;
-      break;
+    default:
+      return UNSOLVED;
     }
 
-    if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
     return SOLVED;
   }
 
@@ -579,23 +647,26 @@
     glp_smcp smcp;
     glp_init_smcp(&smcp);
 
-    switch (_message_level) {
-    case MESSAGE_NO_OUTPUT:
-      smcp.msg_lev = GLP_MSG_OFF;
+    smcp.msg_lev = _message_level;
+    smcp.meth = GLP_DUAL;
+    smcp.presolve = _presolve;
+
+    // If the basis is not valid we get an error return value.
+    // In this case we can try to create a new basis.
+    switch (glp_simplex(lp, &smcp)) {
+    case 0:
       break;
-    case MESSAGE_ERROR_MESSAGE:
-      smcp.msg_lev = GLP_MSG_ERR;
+    case GLP_EBADB:
+    case GLP_ESING:
+    case GLP_ECOND:
+      glp_term_out(false);
+      glp_adv_basis(lp, 0);
+      glp_term_out(true);
+      if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
       break;
-    case MESSAGE_NORMAL_OUTPUT:
-      smcp.msg_lev = GLP_MSG_ON;
-      break;
-    case MESSAGE_FULL_OUTPUT:
-      smcp.msg_lev = GLP_MSG_ALL;
-      break;
+    default:
+      return UNSOLVED;
     }
-    smcp.meth = GLP_DUAL;
-
-    if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
     return SOLVED;
   }
 
@@ -813,24 +884,18 @@
     }
   }
 
-  void GlpkLp::presolver(bool b) {
-    lpx_set_int_parm(lp, LPX_K_PRESOL, b ? 1 : 0);
-  }
-
-  void GlpkLp::messageLevel(MessageLevel m) {
-    _message_level = m;
+  void GlpkLp::presolver(bool presolve) {
+    _presolve = presolve;
   }
 
   // GlpkMip members
 
   GlpkMip::GlpkMip()
-    : LpBase(), GlpkBase(), MipSolver() {
-    messageLevel(MESSAGE_NO_OUTPUT);
+    : LpBase(), MipSolver(), GlpkBase() {
   }
 
   GlpkMip::GlpkMip(const GlpkMip& other)
-    : LpBase(), GlpkBase(other), MipSolver() {
-    messageLevel(MESSAGE_NO_OUTPUT);
+    : LpBase(), MipSolver(), GlpkBase(other) {
   }
 
   void GlpkMip::_setColType(int i, GlpkMip::ColTypes col_type) {
@@ -859,42 +924,32 @@
     glp_smcp smcp;
     glp_init_smcp(&smcp);
 
-    switch (_message_level) {
-    case MESSAGE_NO_OUTPUT:
-      smcp.msg_lev = GLP_MSG_OFF;
-      break;
-    case MESSAGE_ERROR_MESSAGE:
-      smcp.msg_lev = GLP_MSG_ERR;
-      break;
-    case MESSAGE_NORMAL_OUTPUT:
-      smcp.msg_lev = GLP_MSG_ON;
-      break;
-    case MESSAGE_FULL_OUTPUT:
-      smcp.msg_lev = GLP_MSG_ALL;
-      break;
-    }
+    smcp.msg_lev = _message_level;
     smcp.meth = GLP_DUAL;
 
-    if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
+    // If the basis is not valid we get an error return value.
+    // In this case we can try to create a new basis.
+    switch (glp_simplex(lp, &smcp)) {
+    case 0:
+      break;
+    case GLP_EBADB:
+    case GLP_ESING:
+    case GLP_ECOND:
+      glp_term_out(false);
+      glp_adv_basis(lp, 0);
+      glp_term_out(true);
+      if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
+      break;
+    default:
+      return UNSOLVED;
+    }
+
     if (glp_get_status(lp) != GLP_OPT) return SOLVED;
 
     glp_iocp iocp;
     glp_init_iocp(&iocp);
 
-    switch (_message_level) {
-    case MESSAGE_NO_OUTPUT:
-      iocp.msg_lev = GLP_MSG_OFF;
-      break;
-    case MESSAGE_ERROR_MESSAGE:
-      iocp.msg_lev = GLP_MSG_ERR;
-      break;
-    case MESSAGE_NORMAL_OUTPUT:
-      iocp.msg_lev = GLP_MSG_ON;
-      break;
-    case MESSAGE_FULL_OUTPUT:
-      iocp.msg_lev = GLP_MSG_ALL;
-      break;
-    }
+    iocp.msg_lev = _message_level;
 
     if (glp_intopt(lp, &iocp) != 0) return UNSOLVED;
     return SOLVED;
@@ -940,13 +995,9 @@
     return glp_mip_obj_val(lp);
   }
 
-  GlpkMip* GlpkMip::_newSolver() const { return new GlpkMip; }
-  GlpkMip* GlpkMip::_cloneSolver() const {return new GlpkMip(*this); }
+  GlpkMip* GlpkMip::newSolver() const { return new GlpkMip; }
+  GlpkMip* GlpkMip::cloneSolver() const {return new GlpkMip(*this); }
 
   const char* GlpkMip::_solverName() const { return "GlpkMip"; }
 
-  void GlpkMip::messageLevel(MessageLevel m) {
-    _message_level = m;
-  }
-
 } //END OF NAMESPACE LEMON