source/target.cpp

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