view open.cpp @ 562:dfeb5ef768da

Usually a commitment phobe but everybody has they're first time. Include mant structural changes and additional definition in line with what Christophe has asked for. Some of the schemas are more complicated than Id like - I will try to think of more elegant ways of specification.

extern "C" {
#include "audioDB_API.h"
}
#include "audioDB-internals.h"

static bool audiodb_check_header(adb_header_t *header) {
  /* FIXME: use syslog() or write to stderr or something to give the
     poor user some diagnostics. */
  if(header->magic == ADB_OLD_MAGIC) {
    return false;
  }
  if(header->magic != ADB_MAGIC) {
    return false;
  }
  if(header->version != ADB_FORMAT_VERSION) {
    return false;
  }
  if(header->headerSize != ADB_HEADER_SIZE) {
    return false;
  }
  return true;
}

static int audiodb_collect_keys(adb_t *adb) {
  char *key_table = 0;
  size_t key_table_length = 0;

  if(adb->header->length > 0) {
    unsigned nfiles = adb->header->numFiles;
    key_table_length = align_page_up(nfiles * ADB_FILETABLE_ENTRY_SIZE);
    mmap_or_goto_error(char *, key_table, adb->header->fileTableOffset, key_table_length);
    for (unsigned int k = 0; k < nfiles; k++) {
      adb->keys->push_back(key_table + k*ADB_FILETABLE_ENTRY_SIZE);
      (*adb->keymap)[(key_table + k*ADB_FILETABLE_ENTRY_SIZE)] = k;
    }
    munmap(key_table, key_table_length);
  }

  return 0;

 error:
  maybe_munmap(key_table, key_table_length);
  return 1;
}

static int audiodb_collect_track_lengths(adb_t *adb) {
  uint32_t *track_table = 0;
  size_t track_table_length = 0;
  if(adb->header->length > 0) {
    unsigned nfiles = adb->header->numFiles;
    track_table_length = align_page_up(nfiles * ADB_TRACKTABLE_ENTRY_SIZE);
    mmap_or_goto_error(uint32_t *, track_table, adb->header->trackTableOffset, track_table_length);
    off_t offset = 0;
    for (unsigned int k = 0; k < nfiles; k++) {
      uint32_t track_length = track_table[k];
      adb->track_lengths->push_back(track_length);
      adb->track_offsets->push_back(offset);
      offset += track_length * adb->header->dim * sizeof(double);
    }
    munmap(track_table, track_table_length);
  }

  return 0;

 error:
  maybe_munmap(track_table, track_table_length);
  return 1;
}

adb_t *audiodb_open(const char *path, int flags) {
  adb_t *adb = 0;
  int fd = -1;

  flags &= (O_RDONLY|O_RDWR);
  fd = open(path, flags);
  if(fd == -1) {
    goto error;
  }
  if(acquire_lock(fd, flags == O_RDWR)) {
    goto error;
  }

  adb = (adb_t *) calloc(1, sizeof(adb_t));
  if(!adb) {
    goto error;
  }
  adb->fd = fd;
  adb->flags = flags;
  adb->path = (char *) malloc(1+strlen(path));
  if(!(adb->path)) {
    goto error;
  }
  strcpy(adb->path, path);

  adb->header = (adb_header_t *) malloc(sizeof(adb_header_t));
  if(!(adb->header)) {
    goto error;
  }
  if(read(fd, (char *) adb->header, ADB_HEADER_SIZE) != ADB_HEADER_SIZE) {
    goto error;
  }
  if(!audiodb_check_header(adb->header)) {
    goto error;
  }

  adb->keys = new std::vector<std::string>;
  if(!adb->keys) {
    goto error;
  }
  adb->keymap = new std::map<std::string,uint32_t>;
  if(!adb->keymap) {
    goto error;
  }
  if(audiodb_collect_keys(adb)) {
    goto error;
  }
  adb->track_lengths = new std::vector<uint32_t>;
  if(!adb->track_lengths) {
    goto error;
  }
  adb->track_lengths->reserve(adb->header->numFiles);
  adb->track_offsets = new std::vector<off_t>;
  if(!adb->track_offsets) {
    goto error;
  }
  adb->track_offsets->reserve(adb->header->numFiles);
  if(audiodb_collect_track_lengths(adb)) {
    goto error;
  }
  adb->cached_lsh = 0;
  return adb;

 error:
  if(adb) {
    if(adb->header) {
      free(adb->header);
    }
    if(adb->path) {
      free(adb->path);
    }
    if(adb->keys) {
      delete adb->keys;
    }
    if(adb->keymap) {
      delete adb->keymap;
    }
    if(adb->track_lengths) {
      delete adb->track_lengths;
    }
    free(adb);
  }
  if(fd != -1) {
    close(fd);
  }
  return NULL;
}