patch-pre2.0.8 linux/arch/ppc/boot/compressed/misc.c

• Lines: 431
• Date: Mon May 27 12:00:57 1996
• Orig file: pre2.0.7/linux/arch/ppc/boot/compressed/misc.c
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file pre2.0.7/linux/arch/ppc/boot/compressed/misc.c linux/arch/ppc/boot/compressed/misc.c
@@ -0,0 +1,430 @@
+/*
+ * misc.c
+ * 
+ * This is a collection of several routines from gzip-1.0.3 
+ * adapted for Linux.
+ *
+ * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
+ * puts by Nick Holloway 1993
+ */
+
+#include "gzip.h"
+#include "lzw.h"
+
+
+#define EOF -1
+
+DECLARE(uch, inbuf, INBUFSIZ);
+DECLARE(uch, outbuf, OUTBUFSIZ+OUTBUF_EXTRA);
+DECLARE(uch, window, WSIZE);
+
+unsigned outcnt;
+unsigned insize;
+unsigned inptr;
+
+extern char input_data[];
+extern int input_len;
+
+int input_ptr;
+
+int method, exit_code, part_nb, last_member;
+int test = 0;
+int force = 0;
+int verbose = 1;
+long bytes_in, bytes_out;
+
+char *output_data;
+unsigned long output_ptr;
+
+extern int end;
+long free_mem_ptr = (long)&end;
+
+int to_stdout = 0;
+int hard_math = 0;
+
+void (*work)(int inf, int outf);
+void makecrc(void);
+
+local int get_method(int);
+
+char *vidmem = (char *)0xC00B8000;
+int lines, cols;
+int orig_x, orig_y;
+
+void puts(const char *);
+
+void *malloc(int size)
+{
+	void *p;
+
+	if (size <0) error("Malloc error\n");
+	if (free_mem_ptr <= 0) error("Memory error\n");
+
+   while(1) {
+	free_mem_ptr = (free_mem_ptr + 3) & ~3;	/* Align */
+
+	p = (void *)free_mem_ptr;
+	free_mem_ptr += size;
+
+	/*
+  	 * The part of the compressed kernel which has already been expanded
+	 * is no longer needed. Therefore we can reuse it for malloc.
+	 * With bigger kernels, this is necessary.
+	 */
+          
+	if (free_mem_ptr < (long)&end) {
+		if (free_mem_ptr > (long)&input_data[input_ptr])
+			error("\nOut of memory\n");
+
+		return p;
+	}
+#if 0	
+	if (free_mem_ptr < 0x90000)
+#endif	
+	return p;
+	puts("large kernel, low 1M tight...");
+	free_mem_ptr = (long)input_data;
+	}
+}
+
+void free(void *where)
+{	/* Don't care */
+}
+
+static void scroll()
+{
+	int i;
+
+	memcpy ( vidmem, vidmem + cols * 2, ( lines - 1 ) * cols * 2 );
+	for ( i = ( lines - 1 ) * cols * 2; i < lines * cols * 2; i += 2 )
+		vidmem[i] = ' ';
+}
+
+void puts(const char *s)
+{
+	int x,y;
+	char c;
+
+#if 0	
+	x = SCREEN_INFO.orig_x;
+	y = SCREEN_INFO.orig_y;
+#else
+	x = orig_x;
+	y = orig_y;
+#endif	
+
+	while ( ( c = *s++ ) != '\0' ) {
+		if ( c == '\n' ) {
+			x = 0;
+			if ( ++y >= lines ) {
+				scroll();
+				y--;
+			}
+		} else {
+			vidmem [ ( x + cols * y ) * 2 ] = c; 
+			if ( ++x >= cols ) {
+				x = 0;
+				if ( ++y >= lines ) {
+					scroll();
+					y--;
+				}
+			}
+		}
+	}
+
+#if 0	
+	SCREEN_INFO.orig_x = x;
+	SCREEN_INFO.orig_y = y;
+#else
+	orig_x = x;
+	orig_y = y;
+#endif	
+}
+
+__ptr_t memset(__ptr_t s, int c, size_t n)
+{
+	int i;
+	char *ss = (char*)s;
+
+	for (i=0;i<n;i++) ss[i] = c;
+}
+
+__ptr_t memcpy(__ptr_t __dest, __const __ptr_t __src,
+			    size_t __n)
+{
+	int i;
+	char *d = (char *)__dest, *s = (char *)__src;
+
+	for (i=0;i<__n;i++) d[i] = s[i];
+}
+
+int memcmp(__ptr_t __dest, __const __ptr_t __src,
+			    size_t __n)
+{
+	int i;
+	char *d = (char *)__dest, *s = (char *)__src;
+
+	for (i=0;i<__n;i++, d++, s++)
+	{
+		if (*d != *s)
+		{
+			return (*s - *d);
+		}
+	}
+	return (0);
+}
+
+extern ulg crc_32_tab[];   /* crc table, defined below */
+
+/* ===========================================================================
+ * Run a set of bytes through the crc shift register.  If s is a NULL
+ * pointer, then initialize the crc shift register contents instead.
+ * Return the current crc in either case.
+ */
+ulg updcrc(s, n)
+    uch *s;                 /* pointer to bytes to pump through */
+    unsigned n;             /* number of bytes in s[] */
+{
+    register ulg c;         /* temporary variable */
+
+    static ulg crc = (ulg)0xffffffffL; /* shift register contents */
+
+    if (s == NULL) {
+	c = 0xffffffffL;
+    } else {
+	c = crc;
+	while (n--) {
+	    c = crc_32_tab[((int)c ^ (*s++)) & 0xff] ^ (c >> 8);
+	}
+    }
+    crc = c;
+    return c ^ 0xffffffffL;       /* (instead of ~c for 64-bit machines) */
+}
+
+/* ===========================================================================
+ * Clear input and output buffers
+ */
+void clear_bufs()
+{
+    outcnt = 0;
+    insize = inptr = 0;
+    bytes_in = bytes_out = 0L;
+}
+
+/* ===========================================================================
+ * Fill the input buffer. This is called only when the buffer is empty
+ * and at least one byte is really needed.
+ */
+int fill_inbuf()
+{
+    int len, i;
+
+    /* Read as much as possible */
+puts("*");    
+    insize = 0;
+    do {
+	len = INBUFSIZ-insize;
+	if (len > (input_len-input_ptr+1)) len=input_len-input_ptr+1;
+        if (len == 0 || len == EOF) break;
+
+        for (i=0;i<len;i++) inbuf[insize+i] = input_data[input_ptr+i];
+	insize += len;
+	input_ptr += len;
+    } while (insize < INBUFSIZ);
+
+    if (insize == 0) {
+	error("unable to fill buffer\n");
+    }
+    bytes_in += (ulg)insize;
+    inptr = 1;
+    return inbuf[0];
+}
+
+/* ===========================================================================
+ * Write the output window window[0..outcnt-1] and update crc and bytes_out.
+ * (Used for the decompressed data only.)
+ */
+void flush_window()
+{
+    if (outcnt == 0) return;
+    updcrc(window, outcnt);
+
+    memcpy(&output_data[output_ptr], (char *)window, outcnt);
+
+    bytes_out += (ulg)outcnt;
+    output_ptr += (ulg)outcnt;
+    outcnt = 0;
+}
+
+/*
+ * Code to compute the CRC-32 table. Borrowed from 
+ * gzip-1.0.3/makecrc.c.
+ */
+
+ulg crc_32_tab[256];
+
+void
+makecrc(void)
+{
+/* Not copyrighted 1990 Mark Adler	*/
+
+  unsigned long c;      /* crc shift register */
+  unsigned long e;      /* polynomial exclusive-or pattern */
+  int i;                /* counter for all possible eight bit values */
+  int k;                /* byte being shifted into crc apparatus */
+
+  /* terms of polynomial defining this crc (except x^32): */
+  static int p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26};
+
+  /* Make exclusive-or pattern from polynomial */
+  e = 0;
+  for (i = 0; i < sizeof(p)/sizeof(int); i++)
+    e |= 1L << (31 - p[i]);
+
+  crc_32_tab[0] = 0;
+
+  for (i = 1; i < 256; i++)
+  {
+    c = 0;
+    for (k = i | 256; k != 1; k >>= 1)
+    {
+      c = c & 1 ? (c >> 1) ^ e : c >> 1;
+      if (k & 1)
+        c ^= e;
+    }
+    crc_32_tab[i] = c;
+  }
+}
+
+void error(char *x)
+{
+	puts("\n\n");
+	puts(x);
+	puts("\n\n -- System halted");
+
+	while(1);	/* Halt */
+}
+
+#if 0
+#define STACK_SIZE (4096)
+
+long user_stack [STACK_SIZE];
+
+struct {
+	long * a;
+	short b;
+	} stack_start = { & user_stack [STACK_SIZE] , KERNEL_DS };
+#endif
+
+void decompress_kernel()
+{
+#if 0	
+	if (SCREEN_INFO.orig_video_mode == 7)
+		vidmem = (char *) 0xb0000;
+	else
+		vidmem = (char *) 0xb8000;
+
+	lines = SCREEN_INFO.orig_video_lines;
+	cols = SCREEN_INFO.orig_video_cols;
+
+	if (EXT_MEM_K < 1024) error("<2M of mem\n");
+	output_data = (char *)0x100000;	/* Points to 1M */
+#else
+	output_data = (char *)0x0;	/* Points to 0 */
+	lines = 25;
+	cols = 80;
+	orig_x = 0;
+	orig_y = 24;
+#endif	
+
+	output_ptr = 0;
+
+	exit_code = 0;
+	test = 0;
+	input_ptr = 0;
+	part_nb = 0;
+
+	clear_bufs();
+	makecrc();
+
+	puts("Uncompressing Linux...");
+
+	method = get_method(0);
+
+	work(0, 0);
+
+	puts("done.\n");
+
+	puts("Now booting the kernel\n");
+}
+
+/* ========================================================================
+ * Check the magic number of the input file and update ofname if an
+ * original name was given and to_stdout is not set.
+ * Return the compression method, -1 for error, -2 for warning.
+ * Set inptr to the offset of the next byte to be processed.
+ * This function may be called repeatedly for an input file consisting
+ * of several contiguous gzip'ed members.
+ * IN assertions: there is at least one remaining compressed member.
+ *   If the member is a zip file, it must be the only one.
+ */
+local int get_method(in)
+    int in;        /* input file descriptor */
+{
+    uch flags;
+    char magic[2]; /* magic header */
+
+    magic[0] = (char)get_byte();
+    magic[1] = (char)get_byte();
+
+    method = -1;                 /* unknown yet */
+    part_nb++;                   /* number of parts in gzip file */
+    last_member = 0;
+    /* assume multiple members in gzip file except for record oriented I/O */
+
+    if (memcmp(magic, GZIP_MAGIC, 2) == 0
+        || memcmp(magic, OLD_GZIP_MAGIC, 2) == 0) {
+
+	work = unzip;
+	method = (int)get_byte();
+	flags  = (uch)get_byte();
+	if ((flags & ENCRYPTED) != 0)
+	    error("Input is encrypted\n");
+	if ((flags & CONTINUATION) != 0)
+	       error("Multi part input\n");
+	if ((flags & RESERVED) != 0) {
+	    error("Input has invalid flags\n");
+	    exit_code = ERROR;
+	    if (force <= 1) return -1;
+	}
+	(ulg)get_byte();	/* Get timestamp */
+	((ulg)get_byte()) << 8;
+	((ulg)get_byte()) << 16;
+	((ulg)get_byte()) << 24;
+
+	(void)get_byte();  /* Ignore extra flags for the moment */
+	(void)get_byte();  /* Ignore OS type for the moment */
+
+	if ((flags & EXTRA_FIELD) != 0) {
+	    unsigned len = (unsigned)get_byte();
+	    len |= ((unsigned)get_byte())<<8;
+	    while (len--) (void)get_byte();
+	}
+
+	/* Get original file name if it was truncated */
+	if ((flags & ORIG_NAME) != 0) {
+	    if (to_stdout || part_nb > 1) {
+		/* Discard the old name */
+		while (get_byte() != 0) /* null */ ;
+	    } else {
+	    } /* to_stdout */
+	} /* orig_name */
+
+	/* Discard file comment if any */
+	if ((flags & COMMENT) != 0) {
+	    while (get_byte() != 0) /* null */ ;
+	}
+    } else
+	error("unknown compression method");
+    return method;
+}