source/target.cpp

   1 /* $Id$
   2
   3 This file is part of builder
   4 Copyright © 2006-2007 Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include <msp/path/utils.h>
   9 #include <msp/time/utils.h>
  10 #include "action.h"
  11 #include "builder.h"
  12 #include "package.h"
  13 #include "target.h"
  14
  15 using namespace std;
  16 using namespace Msp;
  17
  18 /**
  19 Tries to locate a target that will help getting this target built.  If all
  20 dependencies are up-to-date, returns this target.  If there are no targets
  21 ready to be built (maybe because they are being built right now), returns 0.
  22 */
  23 Target *Target::get_buildable_target()
  24 {
  25         if(!rebuild)
  26                 return 0;
  27
  28         bool self_ok=!building;
  29         for(TargetList::iterator i=depends.begin(); i!=depends.end(); ++i)
  30         {
  31                 Target *tgt=(*i)->get_buildable_target();
  32                 if(tgt)
  33                         return tgt;
  34                 else if((*i)->get_rebuild())
  35                         self_ok=false;
  36         }
  37
  38         if(self_ok)
  39                 return this;
  40
  41         return 0;
  42 }
  43
  44 void Target::add_depend(Target *dep)
  45 {
  46         if(dep==this)
  47                 throw InvalidParameterValue("A target can't depend on itself");
  48         depends.push_back(dep);
  49         dep->rdepends.push_back(this);
  50 }
  51
  52 /**
  53 Prepares the target by recursively preparing dependencies, then checking
  54 whether rebuilding is needed.  A flag is used to prevent unnecessary
  55 executions.
  56 */
  57 void Target::prepare()
  58 {
  59         if(prepared)
  60                 return;
  61
  62         prepared=true;
  63         for(TargetList::iterator i=depends.begin(); i!=depends.end(); ++i)
  64                 (*i)->prepare();
  65
  66         check_rebuild();
  67
  68 }
  69
  70 /**
  71 Returns the number of targets that need to be rebuilt in order to get this
  72 target up-to-date.
  73 */
  74 unsigned Target::count_rebuild()
  75 {
  76         if(counted)
  77                 return 0;
  78
  79         counted=true;
  80         unsigned count=rebuild;
  81         for(TargetList::iterator i=depends.begin(); i!=depends.end(); ++i)
  82                 count+=(*i)->count_rebuild();
  83         return count;
  84 }
  85
  86 /**
  87 Changes the mtime of the target to the current time.
  88 */
  89 void Target::touch()
  90 {
  91         mtime=Time::now();
  92 }
  93
  94 Target::Target(Builder &b, const Package *p, const string &n):
  95         builder(b),
  96         package(p),
  97         name(n),
  98         buildable(false),
  99         building(false),
 100         rebuild(false),
 101         deps_ready(false),
 102         prepared(false),
 103         counted(false)
 104 {
 105         builder.add_target(this);
 106
 107         struct stat st;
 108         if(!Path::stat(name, st))
 109                 mtime=Time::TimeStamp::from_unixtime(st.st_mtime);
 110 }
 111
 112 void Target::mark_rebuild(const std::string &reason)
 113 {
 114         rebuild=true;
 115         rebuild_reason=reason;
 116 }
 117
 118 /**
 119 Checks if this target needs to be rebuilt and why.
 120 */
 121 void Target::check_rebuild()
 122 {
 123         if(!buildable)
 124                 return;
 125
 126         if(builder.get_build_all())
 127                 mark_rebuild("Rebuilding everything");
 128         else if(!mtime)
 129                 mark_rebuild("Does not exist");
 130         else
 131         {
 132                 for(TargetList::iterator i=depends.begin(); (i!=depends.end() && !rebuild); ++i)
 133                 {
 134                         if((*i)->get_mtime()>mtime)
 135                                 mark_rebuild(Path::basename((*i)->get_name())+" has changed");
 136                         else if((*i)->get_rebuild())
 137                                 mark_rebuild(Path::basename((*i)->get_name())+" needs rebuilding");
 138                 }
 139         }
 140         if(!rebuild && package && package->get_config().get_mtime()>mtime)
 141                 mark_rebuild("Package options changed");
 142 }
 143
 144 /**
 145 Hooks the target up with the given action, then returns it.  This should be
 146 called from the public build() function of buildable targets.
 147 */
 148 Action *Target::build(Action *action)
 149 {
 150         building=true;
 151         action->signal_done.connect(sigc::mem_fun(this, &Target::build_done));
 152         return action;
 153 }
 154
 155 /**
 156 Handles for the build_done signal of Action.
 157 */
 158 void Target::build_done()
 159 {
 160         building=false;
 161         rebuild=false;
 162 }