annotate common.cpp @ 284:cacad987d785

Really finish with the sampling branch, this time merging all of it,
yes, even the last revision.  (The last revision was one that seeded the
RNG with the current time, which is helpful when trying to get multiple
independent-ish samples from the same database...)

#include "audioDB.h"

#if defined(O2_DEBUG)
void sigterm_action(int signal, siginfo_t *info, void *context) {
  exit(128+signal);
}

void sighup_action(int signal, siginfo_t *info, void *context) {
  // FIXME: reread any configuration files
}
#endif

void audioDB::get_lock(int fd, bool exclusive) {
  struct flock lock;
  int status;
  
  lock.l_type = exclusive ? F_WRLCK : F_RDLCK;
  lock.l_whence = SEEK_SET;
  lock.l_start = 0;
  lock.l_len = 0; /* "the whole file" */

 retry:
  do {
    status = fcntl(fd, F_SETLKW, &lock);
  } while (status != 0 && errno == EINTR);
  
  if (status) {
    if (errno == EAGAIN) {
      sleep(1);
      goto retry;
    } else {
      error("fcntl lock error", "", "fcntl");
    }
  }
}

void audioDB::release_lock(int fd) {
  struct flock lock;
  int status;

  lock.l_type = F_UNLCK;
  lock.l_whence = SEEK_SET;
  lock.l_start = 0;
  lock.l_len = 0;

  status = fcntl(fd, F_SETLKW, &lock);

  if (status)
    error("fcntl unlock error", "", "fcntl");
}

void audioDB::error(const char* a, const char* b, const char *sysFunc) {
  if(isServer) {
    /* FIXME: I think this is leaky -- we never delete err.  actually
       deleting it is tricky, though; it gets placed into some
       soap-internal struct with uncertain extent... -- CSR,
       2007-10-01 */
    char *err = new char[256]; /* FIXME: overflows */
    snprintf(err, 255, "%s: %s\n%s", a, b, sysFunc ? strerror(errno) : "");
    /* FIXME: actually we could usefully do with a properly structured
       type, so that we can throw separate faultstring and details.
       -- CSR, 2007-10-01 */
    throw(err);
  } else {
    std::cerr << a << ": " << b << std::endl;
    if (sysFunc) {
      perror(sysFunc);
    }
    exit(1);
  }
}

void audioDB::initRNG() {
  rng = gsl_rng_alloc(gsl_rng_mt19937);
  if(!rng) {
    error("could not allocate Random Number Generator");
  }
  /* FIXME: maybe we should use a real source of entropy? */
  gsl_rng_set(rng, time(NULL));
}

void audioDB::initDBHeader(const char* dbName) {
  if ((dbfid = open(dbName, forWrite ? O_RDWR : O_RDONLY)) < 0) {
    error("Can't open database file", dbName, "open");
  }

  get_lock(dbfid, forWrite);
  // Get the database header info
  dbH = new dbTableHeaderT();
  assert(dbH);
  
  if(read(dbfid, (char *) dbH, O2_HEADERSIZE) != O2_HEADERSIZE) {
    error("error reading db header", dbName, "read");
  }

  if(dbH->magic == O2_OLD_MAGIC) {
    // FIXME: if anyone ever complains, write the program to convert
    // from the old audioDB format to the new...
    error("database file has old O2 header", dbName);
  }

  if(dbH->magic != O2_MAGIC) {
    std::cerr << "expected: " << O2_MAGIC << ", got: " << dbH->magic << std::endl;
    error("database file has incorrect header", dbName);
  }

  if(dbH->version != O2_FORMAT_VERSION) {
    error("database file has incorrect version", dbName);
  }

  if(dbH->headerSize != O2_HEADERSIZE) {
    error("sizeof(dbTableHeader) unexpected: platform ABI mismatch?", dbName);
  }

  CHECKED_MMAP(char *, db, 0, getpagesize());

  // Make some handy tables with correct types
  if(forWrite || (dbH->length > 0)) {
    if(forWrite) {
      fileTableLength = dbH->trackTableOffset - dbH->fileTableOffset;
      trackTableLength = dbH->dataOffset - dbH->trackTableOffset;
      dataBufLength = dbH->timesTableOffset - dbH->dataOffset;
      timesTableLength = dbH->powerTableOffset - dbH->timesTableOffset;
      powerTableLength = dbH->l2normTableOffset - dbH->powerTableOffset;
      l2normTableLength = dbH->dbSize - dbH->l2normTableOffset;
    } else {
      fileTableLength = ALIGN_PAGE_UP(dbH->numFiles * O2_FILETABLE_ENTRY_SIZE);
      trackTableLength = ALIGN_PAGE_UP(dbH->numFiles * O2_TRACKTABLE_ENTRY_SIZE);
      dataBufLength = ALIGN_PAGE_UP(dbH->length);
      timesTableLength = ALIGN_PAGE_UP(2*(dbH->length / dbH->dim));
      powerTableLength = ALIGN_PAGE_UP(dbH->length / dbH->dim);
      l2normTableLength = ALIGN_PAGE_UP(dbH->length / dbH->dim);
    }
    CHECKED_MMAP(char *, fileTable, dbH->fileTableOffset, fileTableLength);
    CHECKED_MMAP(unsigned *, trackTable, dbH->trackTableOffset, trackTableLength);
    /*
     * No more mmap() for dataBuf
     *
     * FIXME: Actually we do do the mmap() in the two cases where it's
     * still "needed": in pointQuery and in l2norm if dbH->length is
     * non-zero.  Removing those cases too (and deleting the dataBuf
     * variable completely) would be cool.  -- CSR, 2007-11-19
     *
     * CHECKED_MMAP(double *, dataBuf, dbH->dataOffset, dataBufLength);
     */
    CHECKED_MMAP(double *, timesTable, dbH->timesTableOffset, timesTableLength);
    CHECKED_MMAP(double *, powerTable, dbH->powerTableOffset, powerTableLength);
    CHECKED_MMAP(double *, l2normTable, dbH->l2normTableOffset, l2normTableLength);
  }
}

void audioDB::initInputFile (const char *inFile) {
  if (inFile) {
    if ((infid = open(inFile, O_RDONLY)) < 0) {
      error("can't open input file for reading", inFile, "open");
    }

    if (fstat(infid, &statbuf) < 0) {
      error("fstat error finding size of input", inFile, "fstat");
    }

    if(dbH->dim == 0 && dbH->length == 0) { // empty database
      // initialize with input dimensionality
      if(read(infid, &dbH->dim, sizeof(unsigned)) != sizeof(unsigned)) {
        error("short read of input file", inFile);
      }
      if(dbH->dim == 0) {
        error("dimensionality of zero in input file", inFile);
      }
    } else {
      unsigned test;
      if(read(infid, &test, sizeof(unsigned)) != sizeof(unsigned)) {
        error("short read of input file", inFile);
      }
      if(dbH->dim == 0) {
        error("dimensionality of zero in input file", inFile);
      }
      if(dbH->dim != test) {      
	std::cerr << "error: expected dimension: " << dbH->dim << ", got : " << test <<std::endl;
	error("feature dimensions do not match database table dimensions", inFile);
      }
    }
    
    if ((indata = (char *) mmap(0, statbuf.st_size, PROT_READ, MAP_SHARED, infid, 0)) == (caddr_t) -1) {
      error("mmap error for input", inFile, "mmap");
    }
  }
}

void audioDB::initTables(const char* dbName, const char* inFile = 0) {
  /* FIXME: initRNG() really logically belongs in the audioDB
     contructor.  However, there are of the order of four constructors
     at the moment, and more to come from API implementation.  Given
     that duplication, I think this is the least worst place to put
     it; the assumption is that nothing which doesn't look at a
     database will need an RNG.  -- CSR, 2008-07-02 */
  initRNG();
  initDBHeader(dbName);
  initInputFile(inFile);
}