39 lines
1.4 KiB
C
39 lines
1.4 KiB
C
/*----------------------------------------------------------------------/
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/ Test if the file is contiguous /
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/----------------------------------------------------------------------*/
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FRESULT test_contiguous_file (
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FIL* fp, /* [IN] Open file object to be checked */
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int* cont /* [OUT] 1:Contiguous, 0:Fragmented or zero-length */
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)
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{
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DWORD clst, clsz, step;
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FSIZE_t fsz;
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FRESULT fr;
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*cont = 0;
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fr = f_lseek(fp, 0); /* Validates and prepares the file */
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if (fr != FR_OK) return fr;
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#if FF_MAX_SS == FF_MIN_SS
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clsz = (DWORD)fp->obj.fs->csize * FF_MAX_SS; /* Cluster size */
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#else
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clsz = (DWORD)fp->obj.fs->csize * fp->obj.fs->ssize;
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#endif
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fsz = f_size(fp);
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if (fsz > 0) {
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clst = fp->obj.sclust - 1; /* A cluster leading the first cluster for first test */
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while (fsz) {
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step = (fsz >= clsz) ? clsz : (DWORD)fsz;
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fr = f_lseek(fp, f_tell(fp) + step); /* Advances file pointer a cluster */
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if (fr != FR_OK) return fr;
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if (clst + 1 != fp->clust) break; /* Is not the cluster next to previous one? */
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clst = fp->clust; fsz -= step; /* Get current cluster for next test */
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}
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if (fsz == 0) *cont = 1; /* All done without fail? */
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}
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return FR_OK;
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}
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