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         bool self_ok=true;
  19         for(TargetList::iterator i=depends.begin(); i!=depends.end(); ++i)
  20         {
  21                 Target *tgt=(*i)->get_buildable_target();
  22                 if(tgt)
  23                         return tgt;
  24                 else if((*i)->get_rebuild())
  25                         self_ok=false;
  26         }
  27
  28         if(self_ok && rebuild && !building)
  29                 return this;
  30
  31         return 0;
  32 }
  33
  34 void Target::add_depend(Target *dep)
  35 {
  36         depends.push_back(dep);
  37         dep->rdepends.push_back(this);
  38 }
  39
  40 /**
  41 Prepares the target by recursively preparing dependencies, then checking
  42 whether rebuilding is needed.  A flag is used to prevent unnecessary
  43 executions.
  44 */
  45 void Target::prepare()
  46 {
  47         if(prepared)
  48                 return;
  49
  50         prepared=true;
  51         for(TargetList::iterator i=depends.begin(); i!=depends.end(); ++i)
  52                 (*i)->prepare();
  53
  54         check_rebuild();
  55
  56 }
  57
  58 /**
  59 Returns the number of targets that need to be rebuilt in order to get this
  60 target up-to-date.
  61 */
  62 unsigned Target::count_rebuild()
  63 {
  64         if(counted)
  65                 return 0;
  66
  67         counted=true;
  68         unsigned count=rebuild;
  69         for(TargetList::iterator i=depends.begin(); i!=depends.end(); ++i)
  70                 count+=(*i)->count_rebuild();
  71         return count;
  72 }
  73
  74 /**
  75 Changes the mtime of the target to the current time.
  76 */
  77 void Target::touch()
  78 {
  79         mtime=Time::now();
  80 }
  81
  82 Target::Target(Builder &b, const Package *p, const string &n):
  83         builder(b),
  84         package(p),
  85         name(n),
  86         buildable(false),
  87         building(false),
  88         rebuild(false),
  89         deps_ready(false),
  90         prepared(false),
  91         counted(false)
  92 {
  93         struct stat st;
  94         if(!Path::stat(name, st))
  95                 mtime=Time::TimeStamp::from_unixtime(st.st_mtime);
  96 }
  97
  98 void Target::mark_rebuild(const std::string &reason)
  99 {
 100         rebuild=true;
 101         rebuild_reason=reason;
 102 }
 103
 104 /**
 105 Checks if this target needs to be rebuilt and why.
 106 */
 107 void Target::check_rebuild()
 108 {
 109         if(!buildable)
 110                 return;
 111
 112         if(builder.get_build_all())
 113                 mark_rebuild("Rebuilding everything");
 114         else if(!mtime)
 115                 mark_rebuild("Does not exist");
 116         else
 117         {
 118                 for(TargetList::iterator i=depends.begin(); (i!=depends.end() && !rebuild); ++i)
 119                 {
 120                         if((*i)->get_mtime()>mtime)
 121                                 mark_rebuild(Path::basename((*i)->get_name())+" has changed");
 122                         else if((*i)->get_rebuild())
 123                                 mark_rebuild(Path::basename((*i)->get_name())+" needs rebuilding");
 124                 }
 125         }
 126         if(!rebuild && package && package->get_config().get_mtime()>mtime)
 127                 mark_rebuild("Package options changed");
 128 }
 129
 130 /**
 131 Hooks the target up with the given action, then returns it.  This should be
 132 called from the public build() function of buildable targets.
 133 */
 134 Action *Target::build(Action *action)
 135 {
 136         building=true;
 137         action->signal_done.connect(sigc::mem_fun(this, &Target::build_done));
 138         return action;
 139 }
 140
 141 /**
 142 Handles for the build_done signal of Action.
 143 */
 144 void Target::build_done()
 145 {
 146         building=false;
 147         rebuild=false;
 148 }