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         if(dep==this)
  40                 throw InvalidParameterValue("A target can't depend on itself");
  41         depends.push_back(dep);
  42         dep->rdepends.push_back(this);
  43 }
  44
  45 /**
  46 Prepares the target by recursively preparing dependencies, then checking
  47 whether rebuilding is needed.  A flag is used to prevent unnecessary
  48 executions.
  49 */
  50 void Target::prepare()
  51 {
  52         if(prepared)
  53                 return;
  54
  55         prepared=true;
  56         for(TargetList::iterator i=depends.begin(); i!=depends.end(); ++i)
  57                 (*i)->prepare();
  58
  59         check_rebuild();
  60
  61 }
  62
  63 /**
  64 Returns the number of targets that need to be rebuilt in order to get this
  65 target up-to-date.
  66 */
  67 unsigned Target::count_rebuild()
  68 {
  69         if(counted)
  70                 return 0;
  71
  72         counted=true;
  73         unsigned count=rebuild;
  74         for(TargetList::iterator i=depends.begin(); i!=depends.end(); ++i)
  75                 count+=(*i)->count_rebuild();
  76         return count;
  77 }
  78
  79 /**
  80 Changes the mtime of the target to the current time.
  81 */
  82 void Target::touch()
  83 {
  84         mtime=Time::now();
  85 }
  86
  87 Target::Target(Builder &b, const Package *p, const string &n):
  88         builder(b),
  89         package(p),
  90         name(n),
  91         buildable(false),
  92         building(false),
  93         rebuild(false),
  94         deps_ready(false),
  95         prepared(false),
  96         counted(false)
  97 {
  98         struct stat st;
  99         if(!Path::stat(name, st))
 100                 mtime=Time::TimeStamp::from_unixtime(st.st_mtime);
 101 }
 102
 103 void Target::mark_rebuild(const std::string &reason)
 104 {
 105         rebuild=true;
 106         rebuild_reason=reason;
 107 }
 108
 109 /**
 110 Checks if this target needs to be rebuilt and why.
 111 */
 112 void Target::check_rebuild()
 113 {
 114         if(!buildable)
 115                 return;
 116
 117         if(builder.get_build_all())
 118                 mark_rebuild("Rebuilding everything");
 119         else if(!mtime)
 120                 mark_rebuild("Does not exist");
 121         else
 122         {
 123                 for(TargetList::iterator i=depends.begin(); (i!=depends.end() && !rebuild); ++i)
 124                 {
 125                         if((*i)->get_mtime()>mtime)
 126                                 mark_rebuild(Path::basename((*i)->get_name())+" has changed");
 127                         else if((*i)->get_rebuild())
 128                                 mark_rebuild(Path::basename((*i)->get_name())+" needs rebuilding");
 129                 }
 130         }
 131         if(!rebuild && package && package->get_config().get_mtime()>mtime)
 132                 mark_rebuild("Package options changed");
 133 }
 134
 135 /**
 136 Hooks the target up with the given action, then returns it.  This should be
 137 called from the public build() function of buildable targets.
 138 */
 139 Action *Target::build(Action *action)
 140 {
 141         building=true;
 142         action->signal_done.connect(sigc::mem_fun(this, &Target::build_done));
 143         return action;
 144 }
 145
 146 /**
 147 Handles for the build_done signal of Action.
 148 */
 149 void Target::build_done()
 150 {
 151         building=false;
 152         rebuild=false;
 153 }