unpackdat: Update algorithm #8
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* recognize two chunks formats * Trim gap before first chunk * Print dat header You have to investigate chunk offsets before cut bin file
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Nice ! Never expected to get pull reqs on this project... |
| @@ -16,15 +19,60 @@ | |||
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| FILE *dbg_stream; | |||
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| #define FMT_CHUNK_EXT 0x80 | |||
| #define CRC_TAIL_LEN 3 | |||
| #define MAX_DAT_OFFSET 0xffffff | |||
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I assume MAX_DAT_OFFSET is to cover the maximum "AH:AM:AL" value ?
| rf->dbuf = malloc(file_len); | ||
| // Allocate max size for output according to offset field dimension | ||
| rf->dbuf_size = MAX_DAT_OFFSET; | ||
| rf->dbuf = malloc(rf->dbuf_size); |
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Ok, but maybe the size should be +1 : if the last chunk has len=0x80 starting at 0xff ff80 then the last byte would overflow.
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| char ver_str[6]; // e.g. LBC ZE1/ VCM | ||
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| uint32_t off17; // 00 00 00 80 |
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If I count properly, this field is not 4-byte aligned in the (packed) struct, correct ?
| printf("\n"); | ||
| } | ||
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| void unpack_dat(FILE *outf, struct datfile *rf, bool trim) { |
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yes, passing in a struct * is good
Can you add a comment for argument "trim"
| temp_addr >>= 8; | ||
| if (temp_addr != (curaddr + DCHUNK_DLEN)) { | ||
| printf("addr skip @ %lX\n", (unsigned long) temp_addr); | ||
| const dat_header_t *dath = (const dat_header_t *)src; |
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I don't like casting a raw buffer to a struct like this, especially if the struct has unaligned bytes. It also leads to assuming host endianness.
Either at least memcpy to your struct (and mark the struct with __attribute packed etc), or copy the elements one by one with reconst_XX() as required.
| const chunk_t *ch = NULL; | ||
| if (ch_header->fmt == FMT_CHUNK_EXT) { | ||
| // 80 SRC TGT LEN 34 82 | ||
| ch = (chunk_t*)((uint8_t*)ch_header + sizeof(chunk_header_t)); |
| } | ||
| // TODO check whether ch buffer is not go beyond the end of file | ||
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| if (ch->cmd != 0x8234) { |
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Here, you're assuming host endianness. Why not memcmp() with pm[] ?
| break; | ||
| } | ||
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| offset = ch->offset_hi << 16 | ch->offset_mid << 8 | ch->offset_low; |
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I would prefer either using a truncated reconst_32() call like I did, or better, adding a reconst_24() to nislib.c+h
| dest = rf->dbuf + offset; | ||
| memcpy(dest, ch->payload, chklen); | ||
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| ch_header = (const chunk_header_t *)((uint8_t*)ch + offsetof(chunk_t, payload) + chklen + CRC_TAIL_LEN); |
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| if (argc !=3) { | ||
| printf("%s <file.dat> <out.dat> : unpack payload to <out.dat> etc\n",argv[0]); | ||
| if (argc < 3) { |
You have to investigate chunk offsets before cut bin file