/******************************************
 * mmap example with apr
 * Sylvain Marechal
 * 25/10/2005
 *****************************************/
#include "apr_general.h"
#include "apr_mmap.h"


/*********************************************
 * mmap
 ********************************************/
void test_mmap( apr_pool_t *pool )
{
  apr_status_t ret;
  apr_mmap_t * mm;
  apr_off_t   offset = 0;
  apr_size_t size = 4000; /*~ page size */
  void * addr = 0;
  apr_file_t * fd;  
  apr_fileperms_t perm = APR_OS_DEFAULT;
  apr_size_t cb;
  char buf[4000]= {0};

  /* open a file and put some data into it 
   * Note: It seems file can't grow, so set the size now 
   * (4000 bytes into it)
   */
  if( apr_file_open( &fd, "./coucou.txt", 
        APR_READ | APR_WRITE | APR_CREATE, perm, pool ) != APR_SUCCESS )
  {
    printf( "test_mmap(): Can't open/create file\n" );
    exit(1);
  }
  cb = sizeof(buf);
  strcpy( buf, "coucou" );
  apr_file_write( fd, buf, &cb );
  
  /* mmap the file */
  ret = apr_mmap_create( &mm, fd, offset, size,
      APR_MMAP_READ | APR_MMAP_WRITE, pool );
  if( ret != APR_SUCCESS )
  {
    char buferror[256] = {0};
    apr_strerror( ret, buferror, sizeof(buferror) -1);
    printf( "test_mmap(): apr_mmap_create() failed (ret=%d, '%s')..\n", 
        ret, buferror );
    exit(1);
  }

  /* read data mmapped */
  ret = apr_mmap_offset( &addr, mm, offset );
  printf( "addr: '%s'\n", (char *)addr );

  /* write some data in addr */
  strcat( (char *)addr, " les amis - blablabla" );
             
  /* close the mmap and the file */
  apr_mmap_delete( mm );
  apr_file_close( fd );

  /* reopen the file to read data */
  apr_file_open( &fd, "./coucou.txt", APR_READ, perm, pool );
  cb = sizeof(buf);
  apr_file_read( fd, buf, &cb );
  printf( "data readen (%d bytes): '%s'\n", cb, buf );
  apr_file_close( fd );

  /* Delete file */
  apr_file_remove( "./coucou.txt", pool );
}

/*********************************************
 * main
 ********************************************/
int main( int argc, char * argv[] )
{
  apr_pool_t *pool;
  if (apr_initialize() != APR_SUCCESS) 
  {
      printf( "Could not initialize\n");
              exit(-1);
  }
  if (apr_pool_create(&pool, NULL) != APR_SUCCESS) 
  {
    printf( "Could not allocate pool\n");
    exit( -1);
  }
  test_mmap( pool );
  apr_pool_destroy( pool );
  return 0;
}