l3.libnazgul/src/free.c

#include "libnazgul.h"

int msgFree(msgSpace * space, void * addr){
  printf("[ FREE 0x%08x ]\n",(int)addr);

  int poolIndex;
  int bufferIndex;
  int poolDataTabFd;
  msgPoolData * poolDataTabAddr;
sem_t * poolDataTabSemFd;
 msgPoolDataTabSemId ressourceSemId;
  sem_t * ressourceSemFd;
  /* on acquiert le droit de modifier les infos sur la ressource */
  /* on protege le tableau des associations */
  poolDataTabSemFd=sem_open(space->poolDataTabSemId,
	  O_CREAT,SEM_DEFAULT_MODE,1);
  if (poolDataTabSemFd == SEM_FAILED){ 
	NZG_ERROR("sem_open : ouverture de la ressource",
		space->poolDataTabSemId);
	return -1; 
  }
  sem_wait(poolDataTabSemFd);

  /* verifier le premier arg du shm_open */

  poolDataTabFd=shm_open(space->poolDataTabId,
	  O_RDWR,
	  MSGSPACE_DEFAULT_MODE);
  if (poolDataTabFd == -1 ) {
	fprintf( stderr, "Allocate %s failed: %s\n",
		(char*)space->poolDataTabId,
		strerror( errno ) );
	return -1;
  }


  poolDataTabAddr = mmap( NULL, (space->poolNb) * sizeof( msgPoolData ),
	  PROT_READ | PROT_WRITE,
	  MAP_SHARED, poolDataTabFd, 0 );

  if( poolDataTabAddr == MAP_FAILED) {
	fprintf( stderr, "mmap failed: %s\n",
		strerror( errno ) );
	return -1;
  }


  // TODO: verouiller semaphore DataInfo
  int err;

  poolIndex=-1; bufferIndex=-1;
  err=msgBufferGetProcAttach(
	  poolDataTabAddr,
	  space->poolNb,
	  &poolIndex,
	  &bufferIndex,
	  addr
	  );

  printf("Found : %d\n",err);
  printf("Freing pool: %d, buffer: %d\n",poolIndex,bufferIndex);
  msgBufferDetachProc(poolDataTabAddr,poolIndex,bufferIndex,addr);

  /* unmapper le buffer */
  void * realAddr=addr;
  int bufferSize=poolDataTabAddr[poolIndex].bufferSize;
  int bufferNb=poolDataTabAddr[poolIndex].bufferNb;
  realAddr=realAddr-poolIndex*bufferSize;
  munmap(realAddr,bufferSize*bufferNb);
  
  /* unmapper le msgPoolDataTab */
  munmap(poolDataTabAddr,(space->poolNb) * sizeof( msgPoolData ));

  close(poolDataTabFd);

  // deverouiller semaphore DataInfo
 sem_post(poolDataTabSemFd);
  sem_close(poolDataTabSemFd);
  
  // deverouiller semaphore ressource.
  msgPoolSemIdIntern(ressourceSemId,space->id,poolIndex);
  ressourceSemFd = sem_open(ressourceSemId,O_CREAT,SEM_DEFAULT_MODE,0);
  if (ressourceSemFd == SEM_FAILED){ 
	NZG_ERROR("sem_open",ressourceSemId);
	goto ERROR;
  }
  sem_post(ressourceSemFd);
  sem_close(ressourceSemFd);
  return 0;
ERROR:
  return -1;
}