view libtests/0001/prog1.c @ 400:8c7453fb5bd9 api-inversion

Invert audioDB::power_flag / audiodb_power()

Here the exciting discovery is that the mmap(), memcpy(), munmap()
sequence is in fact not safe.  In principle an msync() call should be
inserted before unmapping for in-core changes to mmap()ed files to be
flushed to disk.

In this case we work around the problem entirely, by not mmap()ing
anything and doing everything with file descriptors.  Amusingly, that's
probably not desperately safe either, this time because we have to move
the file descriptor position (which is also a shared resource).  dup()
doesn't save us, as the duplicate file descriptor shares a file
position.

This applies also to the filling of data_buffer in the query loop, and
in fact basically any call to lseek(), which is why I'm not fixing it
now.  Solution: if you have multiple threads all acting at once on a
single database, do one audiodb_open() per thread, for now at least.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <fcntl.h>
#include <dirent.h>
#include <unistd.h>
#include <sys/stat.h>
#include <errno.h>
/*
 *  * #define NDEBUG
 *   * */
#include <assert.h>

#include "../../audioDB_API.h"
#include "../test_utils_lib.h"


int main(int argc, char **argv){

    int returnval=0;
    adb_ptr mydbp={0};
    adb_ptr mydbp2={0};
    struct stat statbuf;
    int statval=0;

    char * databasename="testdb";

    //if [ -f testdb ]; then rm -f testdb; fi
    /* remove old directory */
    clean_remove_db(databasename);

    /* create new db */
    //# creation
    //${AUDIODB} -N -d testdb
    mydbp=audiodb_open(databasename,O_RDWR);


    /* open should fail (return NULL), so create a new db */
    if (!mydbp){
        mydbp=audiodb_create(databasename,0,0,0);
    }



    if (!mydbp){
        printf("fail\n");
        returnval=-1;
    }
    

    /* stat testdb - let's make sure that it is there */
    //stat testdb
    statval=stat(databasename, &statbuf);

    if (statval){
       returnval=-1;
    }
    
    audiodb_close(mydbp);

    /* try to create should fail, because db exists now */
    mydbp2=audiodb_create(databasename,0,0,0);

    if (mydbp2){
        returnval=-1;
    }


/* should pass now - db exists */ 
//expect_clean_error_exit ${AUDIODB} -N -d testdb
    mydbp2=audiodb_open(databasename, O_RDONLY);
    if (!mydbp2){
       returnval=-1;
    }

//this test would fail at compile time because of the API interface
//# should fail (no db given)
//expect_clean_error_exit ${AUDIODB} -N


    audiodb_close(mydbp2);

//    printf("returnval:%d\n",returnval);

    return(returnval);
}