Initial import of the CDE 2.1.30 sources from the Open Group.

cde/lib/DtHelp/decompress.c

@@ -0,0 +1,402 @@
+/* $XConsortium: decompress.c /main/4 1995/10/26 12:36:44 rswiston $ */
+/* 
+ * decompress - cat a compressed file
+ *
+ *  (c) Copyright 1993, 1994 Hewlett-Packard Company
+ *  (c) Copyright 1993, 1994 International Business Machines Corp.
+ *  (c) Copyright 1993, 1994 Sun Microsystems, Inc.
+ *  (c) Copyright 1993, 1994 Novell, Inc.
+ */
+
+/* #include "fontmisc.h" */
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include "bufioI.h"
+
+#define BITS	16
+
+/*
+ * a code_int must be able to hold 2**BITS values of type int, and also -1
+ */
+#if BITS > 15
+typedef long int	code_int;
+#else
+typedef int		code_int;
+#endif
+
+typedef long int	  count_int;
+
+#ifdef NO_UCHAR
+ typedef char	char_type;
+#else
+ typedef	unsigned char	char_type;
+#endif /* UCHAR */
+
+static	char_type magic_header[] = { "\037\235" };	/* 1F 9D */
+
+/* Defines for third byte of header */
+#define BIT_MASK	0x1f
+#define BLOCK_MASK	0x80
+/* Masks 0x40 and 0x20 are free.  I think 0x20 should mean that there is
+   a fourth header byte (for expansion).
+*/
+
+#define INIT_BITS 9			/* initial number of bits/code */
+
+#ifdef COMPATIBLE		/* But wrong! */
+# define MAXCODE(n_bits)	(1 << (n_bits) - 1)
+#else
+# define MAXCODE(n_bits)	((1 << (n_bits)) - 1)
+#endif /* COMPATIBLE */
+
+static code_int getcode();
+
+/*
+ * the next two codes should not be changed lightly, as they must not
+ * lie within the contiguous general code space.
+ */ 
+#define FIRST	257	/* first free entry */
+#define	CLEAR	256	/* table clear output code */
+
+#define STACK_SIZE  8192
+
+typedef struct _compressedFILE {
+    BufFilePtr	    file;
+
+    char_type	    *stackp;
+    code_int	    oldcode;
+    char_type	    finchar;
+
+    int		block_compress;
+    int		maxbits;
+    code_int	maxcode, maxmaxcode;
+
+    code_int	free_ent;
+    int		clear_flg;
+    int		n_bits;
+
+    /* bit buffer */
+    int		offset, size;
+    char_type	buf[BITS];
+
+    char_type	    de_stack[STACK_SIZE];
+    char_type	    *tab_suffix;
+    unsigned short  *tab_prefix;
+} CompressedFile;
+
+
+static	int hsize_table[] = {
+    5003,	/* 12 bits - 80% occupancy */
+    9001,	/* 13 bits - 91% occupancy */
+    18013,	/* 14 bits - 91% occupancy */
+    35023,	/* 15 bits - 94% occupancy */
+    69001	/* 16 bits - 95% occupancy */
+};
+
+static int  BufCompressedFill(), BufCompressedSkip(), BufCompressedClose();
+
+BufFilePtr
+_DtHelpCeBufFilePushZ (BufFilePtr f)
+{
+    int		    code;
+    int		    maxbits;
+    int		    hsize;
+    CompressedFile  *file;
+    int		    extra;
+
+    if ((BufFileGet(f) != (magic_header[0] & 0xFF)) ||
+	(BufFileGet(f) != (magic_header[1] & 0xFF)))
+    {
+	return 0;
+    }
+    code = BufFileGet (f);
+    maxbits = code & BIT_MASK;
+    if (maxbits > BITS || maxbits < 12)
+	return 0;
+    hsize = hsize_table[maxbits - 12];
+    extra = (1 << maxbits) * sizeof (char_type) +
+	    hsize * sizeof (unsigned short);
+    file = (CompressedFile *) malloc (sizeof (CompressedFile) + extra);
+    if (!file)
+	return 0;
+    file->file = f;
+    file->maxbits = maxbits;
+    file->block_compress = code & BLOCK_MASK;
+    file->maxmaxcode = 1 << file->maxbits;
+    file->tab_suffix = (char_type *) &file[1];
+    file->tab_prefix = (unsigned short *) (file->tab_suffix + file->maxmaxcode);
+    /*
+     * As above, initialize the first 256 entries in the table.
+     */
+    file->maxcode = MAXCODE(file->n_bits = INIT_BITS);
+    for ( code = 255; code >= 0; code-- ) {
+	file->tab_prefix[code] = 0;
+	file->tab_suffix[code] = (char_type) code;
+    }
+    file->free_ent = ((file->block_compress) ? FIRST : 256 );
+    file->clear_flg = 0;
+    file->offset = 0;
+    file->size = 0;
+    file->stackp = file->de_stack;
+    file->finchar = file->oldcode = getcode (file);
+    if (file->oldcode != -1)
+	*file->stackp++ = file->finchar;
+    return _DtHelpCeBufFileCreate ((char *) file,
+			  BufCompressedFill,
+			  BufCompressedSkip,
+			  BufCompressedClose);
+}
+
+static int
+BufCompressedClose (
+    BufFilePtr	f,
+    int         doClose )
+{
+    CompressedFile  *file;
+    BufFilePtr	    raw;
+
+    file = (CompressedFile *) f->hidden;
+    raw = file->file;
+    free (file);
+    _DtHelpCeBufFileClose (raw, doClose);
+    return 1;
+}
+
+static int
+BufCompressedFill (BufFilePtr f)
+{
+    CompressedFile  *file;
+    register char_type *stackp, *de_stack;
+    register char_type finchar;
+    register code_int code, oldcode, incode;
+    BufChar	    *buf, *bufend;
+
+    file = (CompressedFile *) f->hidden;
+
+    buf = f->buffer;
+    bufend = buf + BUFFILESIZE;
+    stackp = file->stackp;
+    de_stack = file->de_stack;
+    finchar = file->finchar;
+    oldcode = file->oldcode;
+    while (buf < bufend) {
+	while (stackp > de_stack && buf < bufend)
+	    *buf++ = *--stackp;
+
+	if (buf == bufend)
+	    break;
+
+	if (oldcode == -1)
+	    break;
+
+	code = getcode (file);
+	if (code == -1)
+	    break;
+    
+    	if ( (code == CLEAR) && file->block_compress ) {
+	    for ( code = 255; code >= 0; code-- )
+	    	file->tab_prefix[code] = 0;
+	    file->clear_flg = 1;
+	    file->free_ent = FIRST - 1;
+	    if ( (code = getcode (file)) == -1 )	/* O, untimely death! */
+	    	break;
+    	}
+    	incode = code;
+    	/*
+     	 * Special case for KwKwK string.
+     	 */
+    	if ( code >= file->free_ent ) {
+	    *stackp++ = finchar;
+	    code = oldcode;
+    	}
+    
+    	/*
+     	 * Generate output characters in reverse order
+     	 */
+    	while ( code >= 256 )
+    	{
+	    *stackp++ = file->tab_suffix[code];
+	    code = file->tab_prefix[code];
+    	}
+	finchar = file->tab_suffix[code];
+	*stackp++ = finchar;
+    
+    	/*
+     	 * Generate the new entry.
+     	 */
+    	if ( (code=file->free_ent) < file->maxmaxcode ) {
+	    file->tab_prefix[code] = (unsigned short)oldcode;
+	    file->tab_suffix[code] = finchar;
+	    file->free_ent = code+1;
+    	} 
+	/*
+	 * Remember previous code.
+	 */
+	oldcode = incode;
+    }
+    file->oldcode = oldcode;
+    file->stackp = stackp;
+    file->finchar = finchar;
+    if (buf == f->buffer) {
+	f->left = 0;
+	return BUFFILEEOF;
+    }
+    f->bufp = f->buffer + 1;
+    f->left = (buf - f->buffer) - 1;
+    return f->buffer[0];
+}
+
+/*****************************************************************
+ * TAG( getcode )
+ *
+ * Read one code from the standard input.  If BUFFILEEOF, return -1.
+ * Inputs:
+ * 	stdin
+ * Outputs:
+ * 	code or -1 is returned.
+ */
+
+static char_type rmask[9] = {0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff};
+
+static code_int
+getcode(CompressedFile  *file)
+{
+    register code_int code;
+    register int r_off, bits;
+    register char_type *bp = file->buf;
+    register BufFilePtr	raw;
+
+    if ( file->clear_flg > 0 || file->offset >= file->size ||
+	file->free_ent > file->maxcode )
+    {
+	/*
+	 * If the next entry will be too big for the current code
+	 * size, then we must increase the size.  This implies reading
+	 * a new buffer full, too.
+	 */
+	if ( file->free_ent > file->maxcode ) {
+	    file->n_bits++;
+	    if ( file->n_bits == file->maxbits )
+		file->maxcode = file->maxmaxcode;	/* won't get any bigger now */
+	    else
+		file->maxcode = MAXCODE(file->n_bits);
+	}
+	if ( file->clear_flg > 0) {
+    	    file->maxcode = MAXCODE (file->n_bits = INIT_BITS);
+	    file->clear_flg = 0;
+	}
+	bits = file->n_bits;
+	raw = file->file;
+	while (bits > 0 && (code = BufFileGet (raw)) != BUFFILEEOF)
+	{
+	    *bp++ = code;
+	    --bits;
+	}
+	bp = file->buf;
+	if (bits == file->n_bits)
+	    return -1;			/* end of file */
+	file->size = file->n_bits - bits;
+	file->offset = 0;
+	/* Round size down to integral number of codes */
+	file->size = (file->size << 3) - (file->n_bits - 1);
+    }
+    r_off = file->offset;
+    bits = file->n_bits;
+    /*
+     * Get to the first byte.
+     */
+    bp += (r_off >> 3);
+    r_off &= 7;
+    /* Get first part (low order bits) */
+#ifdef NO_UCHAR
+    code = ((*bp++ >> r_off) & rmask[8 - r_off]) & 0xff;
+#else
+    code = (*bp++ >> r_off);
+#endif /* NO_UCHAR */
+    bits -= (8 - r_off);
+    r_off = 8 - r_off;		/* now, offset into code word */
+    /* Get any 8 bit parts in the middle (<=1 for up to 16 bits). */
+    if ( bits >= 8 ) {
+#ifdef NO_UCHAR
+	code |= (*bp++ & 0xff) << r_off;
+#else
+	code |= *bp++ << r_off;
+#endif /* NO_UCHAR */
+	r_off += 8;
+	bits -= 8;
+    }
+    /* high order bits. */
+    code |= (*bp & rmask[bits]) << r_off;
+    file->offset += file->n_bits;
+
+    return code;
+}
+
+static int
+BufCompressedSkip (
+    BufFilePtr	f,
+    int		bytes)
+{
+    int		    c;
+    while (bytes-- && ((c = BufFileGet(f)) != BUFFILEEOF))
+	    ;
+    return c;
+}
+
+int
+_DtHelpCeUncompressFile(
+  char *infile,
+  char *outfile )
+{
+    BufFilePtr	    inputraw, input, output;
+    int		    c;
+    int             inFd, outFd;
+    struct stat     statBuf;
+    CECompressInfoPtr	myInfo;
+    
+
+    inFd = open(infile, O_RDONLY);
+    if (inFd < 0) return -1;
+
+    if (fstat(inFd, &statBuf) < 0)
+	{
+	close(inFd);
+	return -1;
+	}
+
+    outFd = open(outfile, O_CREAT | O_WRONLY, 0666);
+    if (outFd < 0)
+	{
+	close(inFd);
+	return -1;
+	}
+
+    myInfo = (CECompressInfoPtr) malloc (sizeof(CECompressInfo));
+    if (myInfo == NULL)
+      {
+	close(inFd);
+	close(outFd);
+	return -1;
+      }
+
+    myInfo->fd   = inFd;
+    myInfo->size = statBuf.st_size;
+
+    inputraw = _DtHelpCeBufFileRdRawZ (myInfo);
+    input    = _DtHelpCeBufFilePushZ (inputraw);
+    output   = _DtHelpCeBufFileOpenWr (outFd);
+    while ((c = BufFileGet (input)) != -1)
+	BufFilePut (c, output);
+
+    c = myInfo->size;
+
+    _DtHelpCeBufFileClose (input, TRUE);
+    _DtHelpCeBufFileClose (output, TRUE);
+
+    if (c != 0) /* didn't consume all the bytes in the file */
+	return -1;
+
+    return 0;
+}