directory.c

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#include "sysincludes.h"
#include "msdos.h"
#include "stream.h"
#include "mtools.h"
#include "file.h"
#include "fs.h"

/* #define DEBUG */

/*
 * Read a directory entry into caller supplied buffer
 */
struct directory *dir_read(direntry_t *entry, int *error)
{
        int n;
        *error = 0;
        if((n=force_read(entry->Dir, (char *) (&entry->dir), 
                         (mt_off_t) entry->entry * MDIR_SIZE, 
                         MDIR_SIZE)) != MDIR_SIZE) {
                if (n < 0) {
                        *error = -1;
                }
                return NULL;
        }
        return &entry->dir;
}

/*
 * Make a subdirectory grow in length.  Only subdirectories (not root)
 * may grow.  Returns a 0 on success, 1 on failure (disk full), or -1
 * on error.
 */

int dir_grow(Stream_t *Dir, int size)
{
        Stream_t *Stream = GetFs(Dir);
        DeclareThis(FsPublic_t);
        int ret;
        int buflen;
        char *buffer;
        
        if (!getfreeMinClusters(Dir, 1))
                return -1;

        buflen = This->cluster_size * This->sector_size;

        if(! (buffer=malloc(buflen)) ){
                perror("dir_grow: malloc");
                return -1;
        }
                
        memset((char *) buffer, '\0', buflen);
        ret = force_write(Dir, buffer, (mt_off_t) size * MDIR_SIZE, buflen);
        free(buffer);
        if(ret < buflen)
                return -1;
        return 0;
}


void low_level_dir_write(direntry_t *entry)
{
        force_write(entry->Dir, 
                    (char *) (&entry->dir), 
                    (mt_off_t) entry->entry * MDIR_SIZE, MDIR_SIZE);
}


/*
 * Make a directory entry.  Builds a directory entry based on the
 * name, attribute, starting cluster number, and size.  Returns a pointer
 * to a static directory structure.
 */

struct directory *mk_entry(const char *filename, char attr,
                           unsigned int fat, size_t size, time_t date,
                           struct directory *ndir)
{
        struct tm *now;
        time_t date2 = date;
        unsigned char hour, min_hi, min_low, sec;
        unsigned char year, month_hi, month_low, day;

        now = localtime(&date2);
        strncpy(ndir->name, filename, 8);
        strncpy(ndir->ext, filename + 8, 3);
        ndir->attr = attr;
        ndir->ctime_ms = 0;
        hour = now->tm_hour << 3;
        min_hi = now->tm_min >> 3;
        min_low = now->tm_min << 5;
        sec = now->tm_sec / 2;
        ndir->ctime[1] = ndir->time[1] = hour + min_hi;
        ndir->ctime[0] = ndir->time[0] = min_low + sec;
        year = (now->tm_year - 80) << 1;
        month_hi = (now->tm_mon + 1) >> 3;
        month_low = (now->tm_mon + 1) << 5;
        day = now->tm_mday;
        ndir -> adate[1] = ndir->cdate[1] = ndir->date[1] = year + month_hi;
        ndir -> adate[0] = ndir->cdate[0] = ndir->date[0] = month_low + day;

        set_word(ndir->start, fat & 0xffff);
        set_word(ndir->startHi, fat >> 16);
        set_dword(ndir->size, size);
        return ndir;
}

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