Tweak readDir code

This commit is contained in:
Scott Lahteine 2017-11-26 18:19:32 -06:00
parent 51d09bb9c9
commit 82df656cc7

View File

@ -1061,7 +1061,7 @@ int8_t SdBaseFile::readDir(dir_t* dir, char* longFilename) {
while (1) {
n = read(dir, sizeof(dir_t));
if (n != sizeof(dir_t)) return n == 0 ? 0 : -1;
if (n != sizeof(dir_t)) return n ? -1 : 0;
// last entry if DIR_NAME_FREE
if (dir->name[0] == DIR_NAME_FREE) return 0;
@ -1074,13 +1074,16 @@ int8_t SdBaseFile::readDir(dir_t* dir, char* longFilename) {
if (longFilename != NULL && DIR_IS_LONG_NAME(dir)) {
vfat_t* VFAT = (vfat_t*)dir;
// Sanity-check the VFAT entry. The first cluster is always set to zero. And the sequence number should be higher than 0
if (VFAT->firstClusterLow == 0 && (VFAT->sequenceNumber & 0x1F) > 0 && (VFAT->sequenceNumber & 0x1F) <= MAX_VFAT_ENTRIES) {
// TODO: Store the filename checksum to verify if a long-filename-unaware system modified the file table.
n = ((VFAT->sequenceNumber & 0x1F) - 1) * (FILENAME_LENGTH);
for (uint8_t i = 0; i < FILENAME_LENGTH; i++)
longFilename[n + i] = (i < 5) ? VFAT->name1[i] : (i < 11) ? VFAT->name2[i - 5] : VFAT->name3[i - 11];
// If this VFAT entry is the last one, add a NUL terminator at the end of the string
if (VFAT->sequenceNumber & 0x40) longFilename[n + FILENAME_LENGTH] = '\0';
if (VFAT->firstClusterLow == 0) {
const uint8_t seq = VFAT->sequenceNumber & 0x1F;
if (WITHIN(seq, 1, MAX_VFAT_ENTRIES)) {
// TODO: Store the filename checksum to verify if a long-filename-unaware system modified the file table.
n = (seq - 1) * (FILENAME_LENGTH);
for (uint8_t i = 0; i < FILENAME_LENGTH; i++)
longFilename[n + i] = (i < 5) ? VFAT->name1[i] : (i < 11) ? VFAT->name2[i - 5] : VFAT->name3[i - 11];
// If this VFAT entry is the last one, add a NUL terminator at the end of the string
if (VFAT->sequenceNumber & 0x40) longFilename[n + FILENAME_LENGTH] = '\0';
}
}
}
// Return if normal file or subdirectory