44 lines
1.1 KiB
C
44 lines
1.1 KiB
C
#include "fsctl/fugue/cluster.h"
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#include "fsctl/fugue/sector.h"
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#include "fsctl/fugue/utils.h"
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//---
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// Public
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//---
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/* fugue_cluster_is_valid() : check cluster validity */
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//TODO : support FAT12 / FAT32
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int fugue_cluster_is_valid(fugue_fs_t *fs, int cluster_idx)
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{
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void *sector;
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uint16_t id;
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id = FAT_WORD(((uint16_t *)fs->_private.fat0)[cluster_idx]);
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if (id == 0x0000)
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return 0;
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if (cluster_idx == 0)
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return 0;
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/* special check for the root fake cluster */
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if (cluster_idx == 1)
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{
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if (id != 0xffff)
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return -1;
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return 0;
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}
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cluster_idx -= 2;
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sector = (void*)((uintptr_t)(fs->props.cluster_nb_sector * cluster_idx));
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sector = (void*)((uintptr_t)sector + fs->props.sector_root_nb);
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sector = (void*)((uintptr_t)sector * 512);
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sector = (void*)((uintptr_t)sector + (uintptr_t)fs->_private.root);
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for (int i = 0 ; i < fs->props.cluster_nb_sector ; i++)
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{
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if (fugue_sector_is_invalid(sector))
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return -2;
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sector = (void *)((uintptr_t)sector + 512);
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}
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return 0;
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}
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