Aminet 28/Aminet 28 (1998)(GTI - Schatztruhe)[!][Dec 1998].iso/Aminet/dev/c/qtools0.2-src.lha/src/libqtools/database.c

C/C++ Source or Header | 1998-07-13 | 5.5 KB | 187 lines

#define    LIBQTOOLS_CORE
#include <libqtools.h>
#include "../liblists/liblists.h"
#include "database.h"

/*
 * in general the database-system allows completely transparent access to
 * files and/or names out of every possible filetype
 */

struct db globalDB;

/*
 * ============================================================================
 * GetNameEntry
 *
 * returns the original name of the entry or the old alias if not found
 * the database will be updated automatically if the entry does not exists
 * the path will verified
 * ============================================================================
 */
char *GetNameEntryDB(struct db *database, char *aliasname)
{
}

/*
 * ============================================================================
 * GetPathEntry
 *
 * returns the valid path of the entry or 0
 * the database will be updated automatically if the entry does not exists
 * the path will verified and the original name will set to the aliasname
 * ============================================================================
 */
char *GetPathEntryDB(struct db *database, char *aliasname)
{
}

char *VerifyPathDB(struct db *database, char *name)
{
}

/*
 * ============================================================================
 * LoadDatabase
 *
 * loads the disk-representation of the complete database
 * joins lists with the same datatype
 * TODO: remove doubled entries
 * ============================================================================
 */
bool LoadDatabaseDB(struct db *database, char *fileName)
{
  nNewList(db->aliasList);

  return AppendDatabaseDB(database, fileName);
}

bool AppendDatabaseDB(struct db * database, char *fileName)
{
  FILE *dbFile;

  if ((dbFile = fopen(fileName, READ_BINARY))) {
    int dbEnd;

    fseek(dbFile, 0, SEEK_END);
    dbEnd = ftell(dbFile);
    fseek(dbFile, 0, SEEK_BEGINNING);

    while (dbEnd > ftell(dbFile)) {
      struct alist *actList, lastList;
      int dbLength, i;
      bool new = TRUE;

      if (!(actList = (struct alist *)tmalloc(sizeof(struct alist)))) {
    eprintf("failed to allocate database\n");
    return FALSE;
      }
      /* set filetype */
      fread(&actList->fileType, 1, sizeof(filetype), dbFile);
      /* read length of filetype */
      fread(&dbLength, 1, sizeof(int), dbFile);

      /* look if there exists the same datatype before this */
      lastList = (struct alist *)nSucc((struct nnode *)&database->aliasList));
      for (i = database->aliasList.nodes; i > 0; i--) {
    if (actList->fileType == lastList->fileType) {
      new = FALSE;
      tfree(actList);
      actList = lastList;
      break;
    }
      }

      while (dbLength > ftell(dbFile)) {
    struct anode *actNode;

    if (!(actNode = (struct anode *)tmalloc(sizeof(struct anode)))) {
      eprintf("failed to allocate database\n");
      return FALSE;
    }
    /* strings cant be greater than 1k */
    if (!(actNode->aliasname = (char *)tmalloc(1024))) {
      eprintf("failed to allocate database\n");
      return FALSE;
    }
    if (!(actNode->name = (char *)tmalloc(1024))) {
      eprintf("failed to allocate database\n");
      return FALSE;
    }
    if (!(actNode->filename = (char *)tmalloc(1024))) {
      eprintf("failed to allocate database\n");
      return FALSE;
    }
    /* scan the string out */
    fscanf("%s\n%s\n%s\n\0", actNode->aliasname, actNode->name, actNode->filename);
    /* shorten the strings to the real size */
    actNode->aliasname = (char *)trealloc(actNode->aliasname, strlen(actNode->aliasname) + 1);
    actNode->name = (char *)trealloc(actNode->name, strlen(actNode->name) + 1);
    actNode->filename = (char *)trealloc(actNode->filename, strlen(actNode->filename) + 1);
    actNode->data = *((int *)actNode->name);        /* sort by name */

    /* register to the list */
    nEnqueue(&actList->listHeader, &actNode->Node);        /* register sorted */
      }
      fseek(dbFile, dbLength, SEEK_BEGINNING);
      actList->listNode.data = actList->fileType;        /* sort by fileType */

      /* register to the list only if this is a new list */
      if (new)
    nEnqueue(&database->aliasList, &actList->listNode);    /* register sorted */
    }

    fclose(dbFile);
  }

  return TRUE;
}

/*
 * ============================================================================
 * SaveDatabase
 *
 * saves the complete database to the disk-representation
 * ============================================================================
 */
bool SaveDatabaseDB(struct db * database, char *fileName) {
  FILE *dbFile;

  if ((dbFile = fopen(fileName, WRITE_BINARY))) {
    struct alist *actList = (struct alist *)&database->aliasList;

    /* loop through all fileType-lists */
    while ((actList = (struct alist *)nSuccNode(&actList->listNode))) {
      struct anode *actNode = (struct anode *)&actList->listHeader;
      int dbLength = 0, dbPos;

      /* put fileType first */
      fwrite(&actList->listType, 1, sizeof(filetype), dbFile);
      dbPos = ftell(dbFile);
      /* then some space for the seek-able offset */
      fwrite(&dbLength, 1, sizeof(int), dbFile);

      /* loop through all node of a fileType-list */
      while ((actNode = (struct anode *)nSuccNode(&actNode->Node)))
    fprintf("%s\n%s\n%s\n\0", actNode->aliasname, actNode->name, actNode->filename);
      /* this is the offset for the next filetype */
      dbLength = ftell(dbFile);
      /* seek to the offset-specifier */
      fseek(dbFile, dbPos, SEEK_BEGINNING);
      /* save it */
      fwrite(&dbLength, 1, sizeof(int), dbFile);

      /* and return to old position */
      fseek(dbFile, dbLength, SEEK_BEGINNING);
    }

    fclose(dbFile);
  }
  else {
    eprintf("failed to save database %s\n", fileName);
    return FALSE;
  }

  return TRUE;
}