+++ /dev/null
-/* $XConsortium: gunzip.c /main/1 1996/11/03 19:33:23 kaleb $ */
-/* lib/font/fontfile/gunzip.c
- written by Mark Eichin <eichin@kitten.gen.ma.us> September 1996.
- intended for inclusion in X11 public releases. */
-
-#include "fontmisc.h"
-#include <bufio.h>
-#include <zlib.h>
-
-typedef struct _xzip_buf {
- z_stream z;
- int zstat;
- BufChar b[BUFFILESIZE];
- BufChar b_in[BUFFILESIZE];
- BufFilePtr f;
-} xzip_buf;
-
-static int BufZipFileSkip(); /* f, count */
-static int BufZipFileFill(); /* read: f; write: char, f */
-static int BufZipFileClose(); /* f, flag */
-static int BufCheckZipHeader(); /* f */
-
-BufFilePtr
-BufFilePushZIP (f)
- BufFilePtr f;
-{
- xzip_buf *x;
-
- x = (xzip_buf *) xalloc (sizeof (xzip_buf));
- if (!x) return 0;
- /* these are just for raw calloc/free */
- x->z.zalloc = Z_NULL;
- x->z.zfree = Z_NULL;
- x->z.opaque = Z_NULL;
- x->f = f;
-
- /* force inflateInit to allocate it's own history buffer */
- x->z.next_in = Z_NULL;
- x->z.next_out = Z_NULL;
- x->z.avail_in = x->z.avail_out = 0;
-
- /* using negative windowBits sets "nowrap" mode, which turns off
- zlib header checking [undocumented, for gzip compatibility only?] */
- x->zstat = inflateInit2(&(x->z), -MAX_WBITS);
- if (x->zstat != Z_OK) {
- xfree(x);
- return 0;
- }
-
- /* now that the history buffer is allocated, we provide the data buffer */
- x->z.next_out = x->b;
- x->z.avail_out = BUFFILESIZE;
- x->z.next_out = x->b_in;
- x->z.avail_in = 0;
-
- if (BufCheckZipHeader(x->f)) {
- xfree(x);
- return 0;
- }
-
- return BufFileCreate(x,
- BufZipFileFill,
- BufZipFileSkip,
- BufZipFileClose);
-}
-
-static int BufZipFileClose(f, flag)
- BufFilePtr f;
- int flag;
-{
- xzip_buf *x = (xzip_buf *)f->private;
- inflateEnd (&(x->z));
- BufFileClose (x->f, flag);
- xfree (x);
- return 1;
-}
-
-/* here's the real work.
- -- we need to put stuff in f.buffer, update f.left and f.bufp,
- then return the first byte (or BUFFILEEOF).
- -- to do this, we need to get stuff into avail_in, and next_in,
- and call inflate appropriately.
- -- we may also need to add CRC maintenance - if inflate tells us
- Z_STREAM_END, we then have 4bytes CRC and 4bytes length...
- gzio.c:gzread shows most of the mechanism.
- */
-static int BufZipFileFill (f)
- BufFilePtr f;
-{
- xzip_buf *x = (xzip_buf *)f->private;
-
- /* we only get called when left == 0... */
- /* but just in case, deal */
- if (f->left >= 0) {
- f->left--;
- return *(f->bufp++);
- }
- /* did we run out last time? */
- switch (x->zstat) {
- case Z_OK:
- break;
- case Z_STREAM_END:
- case Z_DATA_ERROR:
- case Z_ERRNO:
- return BUFFILEEOF;
- default:
- return BUFFILEEOF;
- }
- /* now we work to consume what we can */
- /* let zlib know what we can handle */
- x->z.next_out = x->b;
- x->z.avail_out = BUFFILESIZE;
-
- /* and try to consume all of it */
- while (x->z.avail_out > 0) {
- /* if we don't have anything to work from... */
- if (x->z.avail_in == 0) {
- /* ... fill the z buf from underlying file */
- int i, c;
- for (i = 0; i < sizeof(x->b_in); i++) {
- c = BufFileGet(x->f);
- if (c == BUFFILEEOF) break;
- x->b_in[i] = c;
- }
- x->z.avail_in += i;
- x->z.next_in = x->b_in;
- }
- /* so now we have some output space and some input data */
- x->zstat = inflate(&(x->z), Z_NO_FLUSH);
- /* the inflation output happens in the f buffer directly... */
- if (x->zstat == Z_STREAM_END) {
- /* deal with EOF, crc */
- break;
- }
- if (x->zstat != Z_OK) {
- break;
- }
- }
- f->bufp = x->b;
- f->left = BUFFILESIZE - x->z.avail_out;
-
- if (f->left >= 0) {
- f->left--;
- return *(f->bufp++);
- } else {
- return BUFFILEEOF;
- }
-}
-
-/* there should be a BufCommonSkip... */
-static int BufZipFileSkip (f, c)
- BufFilePtr f;
- int c;
-{
- /* BufFileRawSkip returns the count unchanged.
- BufCompressedSkip returns 0.
- That means it probably never gets called... */
- int retval = c;
- while(c--) {
- int get = BufFileGet(f);
- if (get == BUFFILEEOF) return get;
- }
- return retval;
-}
-
-/* now we need to duplicate check_header */
-/* contents:
- 0x1f, 0x8b -- magic number
- 1 byte -- method (Z_DEFLATED)
- 1 byte -- flags (mask with RESERVED -> fail)
- 4 byte -- time (discard)
- 1 byte -- xflags (discard)
- 1 byte -- "os" code (discard)
- [if flags & EXTRA_FIELD:
- 2 bytes -- LSBfirst length n
- n bytes -- extra data (discard)]
- [if flags & ORIG_NAME:
- n bytes -- null terminated name (discard)]
- [if flags & COMMENT:
- n bytes -- null terminated comment (discard)]
- [if flags & HEAD_CRC:
- 2 bytes -- crc of headers? (discard)]
- */
-
-/* gzip flag byte -- from gzio.c */
-#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */
-#define HEAD_CRC 0x02 /* bit 1 set: header CRC present */
-#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
-#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
-#define COMMENT 0x10 /* bit 4 set: file comment present */
-#define RESERVED 0xE0 /* bits 5..7: reserved */
-
-#define GET(f) do {c = BufFileGet(f); if (c == BUFFILEEOF) return c;} while(0)
-static int BufCheckZipHeader(f)
- BufFilePtr f;
-{
- int c, flags;
- GET(f); if (c != 0x1f) return 1; /* magic 1 */
- GET(f); if (c != 0x8b) return 2; /* magic 2 */
- GET(f); if (c != Z_DEFLATED) return 3; /* method */
- GET(f); if (c & RESERVED) return 4; /* reserved flags */
- flags = c;
- GET(f); GET(f); GET(f); GET(f); /* time */
- GET(f); /* xflags */
- GET(f); /* os code */
- if (flags & EXTRA_FIELD) {
- int len;
- GET(f); len = c;
- GET(f); len += (c<<8);
- while (len-- >= 0) {
- GET(f);
- }
- }
- if (flags & ORIG_NAME) {
- do { GET(f); } while (c != 0);
- }
- if (flags & COMMENT) {
- do { GET(f); } while (c != 0);
- }
- if (flags & HEAD_CRC) {
- GET(f); GET(f); /* header crc */
- }
- return 0;
-}
projects / rdpsrv / blobdiff