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Added comments.

git-svn-id: svn://svn.cc65.org/cc65/trunk@5549 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
ol.sc 2012-02-24 22:21:54 +00:00
parent d27c7d5a75
commit 7cda476c08

View File

@ -187,37 +187,48 @@ int main(int argc, char* argv[])
dir_addr = get_dir_entry(p_name);
/* Read index block */
if (dio_read(dhandle, dir_entry->key_pointer, &index_block)) {
err_exit("dio_read.4", 1);
}
/* First pointer is header block */
header_addr = index_block.content.addr_lo[0] |
index_block.content.addr_hi[0] << 8;
/* Read header block */
if (dio_read(dhandle, header_addr, &header_block)) {
err_exit("dio_read.5", 1);
}
/* Do some sanity check */
for (index = 0; index < sizeof(info_signature); ++index) {
if (header_block.content.info_block[index] != info_signature[index]) {
err_exit("file signature mismatch", 0);
}
}
/* Check ProDOS storage type in directory entry template */
if (header_block.content.dir_entry.storage_length.storage_type == 2)
{
/* ProDOS sapling file means GEOS Sequential file*/
printf("\nSequential file\n");
/* Remove header block pointer from pointer list */
memmove(&index_block.content.addr_lo[0],
&index_block.content.addr_lo[1], sizeof(index_block.content.addr_lo) - 1);
memmove(&index_block.content.addr_hi[0],
&index_block.content.addr_hi[1], sizeof(index_block.content.addr_hi) - 1);
/* Get file size from ProDOS directory entry template */
size = (unsigned long)(header_block.content.dir_entry.size[0]) |
(unsigned long)(header_block.content.dir_entry.size[1]) << 8 |
(unsigned long)(header_block.content.dir_entry.size[2]) << 16;
} else {
/* ProDOS tree file means GEOS VLIR file */
unsigned vlir_addr;
unsigned long vlir_size;
unsigned char vlir_blocks;
@ -225,32 +236,42 @@ int main(int argc, char* argv[])
printf("\nVLIR file\n");
/* Skip header block pointer */
index = 1;
size = 0;
while (1) {
/* Get next VLIR index pointer from index block */
vlir_addr = index_block.content.addr_lo[index] |
index_block.content.addr_hi[index] << 8;
++index;
/* Check for end of pointer list */
if (vlir_addr == 0) {
break;
}
/* Check for empty VLIRs */
while (header_block.content.vlir_records[record] == 0xFF) {
/* Add empty VLIR index pointer to to master index block */
master_block.content.addr_lo[record] = 0xFF;
master_block.content.addr_hi[record] = 0xFF;
++record;
}
/* Add VLIR index pointer to master index block */
master_block.content.addr_lo[record] = (unsigned char)(vlir_addr );
master_block.content.addr_hi[record] = (unsigned char)(vlir_addr >> 8);
++record;
/* Read VLIR index block */
if (dio_read(dhandle, vlir_addr, &vlir_block)) {
err_exit("dio_read.6", 1);
}
/* Get VLIR size from VLIR index block */
vlir_size = (unsigned long)(vlir_block.content.size_lo[1]) |
(unsigned long)(vlir_block.content.size_hi[1]) << 8 |
(unsigned long)(vlir_block.content.size_lo[0]) << 16 |
@ -258,35 +279,44 @@ int main(int argc, char* argv[])
printf("VLIR %u size %lu bytes\n", record - 1, vlir_size);
/* Compute VLIR block size */
vlir_blocks = (unsigned char)((vlir_size + 511) / 512);
/* Copy VLIR block pointers from index block to VLIR index block */
memcpy(&vlir_block.content.addr_lo[0],
&index_block.content.addr_lo[index], vlir_blocks);
memcpy(&vlir_block.content.addr_hi[0],
&index_block.content.addr_hi[index], vlir_blocks);
index += vlir_blocks;
/* Write back VLIR index block */
if (dio_write(dhandle, vlir_addr, &vlir_block)) {
err_exit("dio_write.1", 1);
}
index += vlir_blocks;
size += vlir_size;
/* Add VLIR size to file size */
size += vlir_size;
}
/* Replace (by now completely read) index block with
(by now completely created) master index block */
index_block = master_block;
}
printf("File size %lu bytes\n\n", size);
/* Set file size in index block */
index_block.content.size_lo[1] = (unsigned char)(size );
index_block.content.size_hi[1] = (unsigned char)(size >> 8);
index_block.content.size_lo[0] = (unsigned char)(size >> 16);
index_block.content.size_hi[0] = (unsigned char)(size >> 24);
/* Write index block */
if (dio_write(dhandle, dir_entry->key_pointer, &index_block)) {
err_exit("dio_write.2", 1);
}
/* Copy selected fields from directory entry template to directory block */
dir_entry->storage_length = header_block.content.dir_entry.storage_length;
memcpy(dir_entry->file_name, header_block.content.dir_entry.file_name, 15);
dir_entry->file_type = header_block.content.dir_entry.file_type;
@ -299,10 +329,12 @@ int main(int argc, char* argv[])
dir_entry->aux_type = header_addr;
dir_entry->last_mod = header_block.content.dir_entry.last_mod;
/* Write directory block */
if (dio_write(dhandle, dir_addr, &dir_block)) {
err_exit("dio_write.3", 1);
}
/* We're done */
if (dio_close(dhandle)) {
err_exit("dio_close", 1);
}