/*
- * gunzip65 - a gunzip utility for 6502-based machines.
- *
- * Piotr Fusik <fox@scene.pl>
- *
- * This should be considered as a test of my zlib-compatible library
- * rather than a real application.
- * It's not user-friendly, fault-tolerant, whatever.
- * However, it really works for real GZIP files, provided they are small
- * enough to fit in buffer[] (after decompression!).
- */
+** gunzip65 - a gunzip utility for 6502-based machines.
+**
+** Piotr Fusik <fox@scene.pl>
+**
+** This should be considered as a test of my zlib-compatible library
+** rather than a real application.
+** It's not user-friendly, fault-tolerant, whatever.
+** However, it really works for real GZIP files, provided they are small
+** enough to fit in buffer[] (after decompression!).
+*/
#include <stdio.h>
#include <string.h>
#include <zlib.h>
+#ifdef __CC65__
+#include <stdlib.h>
+#include <cc65.h>
+#endif
+
#ifndef __CC65__
/*
- * Emulate inflatemem() if using original zlib.
- * As you can see, this program is quite portable.
- */
+** Emulate inflatemem() if using original zlib.
+** As you can see, this program is quite portable.
+*/
unsigned inflatemem(char* dest, const char* source)
{
z_stream stream;
#endif /* __CC65__ */
/*
- * Structure of a GZIP file:
- *
- * 1. GZIP header:
- * Offset 0: Signature (2 bytes: 0x1f, 0x8b)
- * Offset 2: Compression method (1 byte: 8 == "deflate")
- * Offset 3: Flags (1 byte: see below)
- * Offset 4: File date and time (4 bytes)
- * Offset 8: Extra flags (1 byte)
- * Offset 9: Target OS (1 byte: DOS, Amiga, Unix, etc.)
- * if (flags & FEXTRA) { 2 bytes of length, then length bytes }
- * if (flags & FNAME) { ASCIIZ filename }
- * if (flags & FCOMMENT) { ASCIIZ comment }
- * if (flags & FHCRC) { 2 bytes of CRC }
- *
- * 2. Deflate compressed data.
- *
- * 3. GZIP trailer:
- * Offset 0: CRC-32 (4 bytes)
- * Offset 4: uncompressed file length (4 bytes)
- */
+** Structure of a GZIP file:
+**
+** 1. GZIP header:
+** Offset 0: Signature (2 bytes: 0x1f, 0x8b)
+** Offset 2: Compression method (1 byte: 8 == "deflate")
+** Offset 3: Flags (1 byte: see below)
+** Offset 4: File date and time (4 bytes)
+** Offset 8: Extra flags (1 byte)
+** Offset 9: Target OS (1 byte: DOS, Amiga, Unix, etc.)
+** if (flags & FEXTRA) { 2 bytes of length, then length bytes }
+** if (flags & FNAME) { ASCIIZ filename }
+** if (flags & FCOMMENT) { ASCIIZ comment }
+** if (flags & FHCRC) { 2 bytes of CRC }
+**
+** 2. Deflate compressed data.
+**
+** 3. GZIP trailer:
+** Offset 0: CRC-32 (4 bytes)
+** Offset 4: uncompressed file length (4 bytes)
+*/
/* Flags in the GZIP header. */
#define FTEXT 1 /* Extra text */
#define FCOMMENT 16 /* File comment */
/*
- * We read whole GZIP file into this buffer.
- * Then we use this buffer for the decompressed data.
- */
+** We read whole GZIP file into this buffer.
+** Then we use this buffer for the decompressed data.
+*/
static unsigned char buffer[26000];
/*
- * Get a 16-bit little-endian unsigned number, using unsigned char* p.
- * On many machines this could be (*(unsigned short*) p),
- * but I really like portability. :-)
- */
+** Get a 16-bit little-endian unsigned number, using unsigned char* p.
+** On many machines this could be (*(unsigned short*) p),
+** but I really like portability. :-)
+*/
#define GET_WORD(p) (*(p) + ((unsigned) (p)[1] << 8))
/* Likewise, for a 32-bit number. */
#define GET_LONG(p) (GET_WORD(p) + ((unsigned long) GET_WORD(p + 2) << 16))
/*
- * Uncompress a GZIP file.
- * On entry, buffer[] should contain the whole GZIP file contents,
- * and the argument complen should be equal to the length of the GZIP file.
- * On return, buffer[] contains the uncompressed data, and the returned
- * value is the length of the uncompressed data.
- */
+** Uncompress a GZIP file.
+** On entry, buffer[] should contain the whole GZIP file contents,
+** and the argument complen should be equal to the length of the GZIP file.
+** On return, buffer[] contains the uncompressed data, and the returned
+** value is the length of the uncompressed data.
+*/
unsigned uncompress_buffer(unsigned complen)
{
unsigned char* ptr;
ptr += 2;
/*
- * calculate length of raw "deflate" data
- * (without the GZIP header and 8-byte trailer)
- */
+ ** calculate length of raw "deflate" data
+ ** (without the GZIP header and 8-byte trailer)
+ */
complen -= (ptr - buffer) + 8;
/*
- * We will move the compressed data to the end of buffer[].
- * Thus the compressed data and the decompressed data (written from
- * the beginning of buffer[]) may overlap, as long as the decompressed
- * data doesn't go further than unread compressed data.
- * ptr2 points to the beginning of compressed data at the end
- * of buffer[].
- */
+ ** We will move the compressed data to the end of buffer[].
+ ** Thus the compressed data and the decompressed data (written from
+ ** the beginning of buffer[]) may overlap, as long as the decompressed
+ ** data doesn't go further than unread compressed data.
+ ** ptr2 points to the beginning of compressed data at the end
+ ** of buffer[].
+ */
ptr2 = buffer + sizeof(buffer) - complen;
/* move the compressed data to end of buffer[] */
memmove(ptr2, ptr, complen);
}
/*
- * Get a filename from standard input.
- */
+** Get a filename from standard input.
+*/
char* get_fname(void)
{
static char filename[100];
FILE* fp;
unsigned length;
+#ifdef __CC65__
+ /* allow user to read exit messages */
+ if (doesclrscrafterexit()) {
+ atexit((void (*)) getchar);
+ }
+#endif /* __CC65__ */
+
/* read GZIP file */
puts("GZIP file name:");
fp = fopen(get_fname(), "rb");
projects / cc65 / blobdiff