diff options
Diffstat (limited to 'nx-X11/lib/font/fontfile/gunzip.c')
-rw-r--r-- | nx-X11/lib/font/fontfile/gunzip.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/nx-X11/lib/font/fontfile/gunzip.c b/nx-X11/lib/font/fontfile/gunzip.c new file mode 100644 index 000000000..8c9c317aa --- /dev/null +++ b/nx-X11/lib/font/fontfile/gunzip.c @@ -0,0 +1,227 @@ +/* $Xorg: gunzip.c,v 1.3 2000/08/17 19:46:37 cpqbld Exp $ */ +/* lib/font/fontfile/gunzip.c + written by Mark Eichin <eichin@kitten.gen.ma.us> September 1996. + intended for inclusion in X11 public releases. */ +/* $XFree86: xc/lib/font/fontfile/gunzip.c,v 1.4 2000/09/19 12:46:08 eich Exp $ */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif +#include <X11/fonts/fontmisc.h> +#include <X11/fonts/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 BufZipFileClose ( BufFilePtr f, int flag ); +static int BufZipFileFill ( BufFilePtr f ); +static int BufZipFileSkip ( BufFilePtr f, int c ); +static int BufCheckZipHeader ( BufFilePtr f ); + +BufFilePtr +BufFilePushZIP (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((char *)x, + BufZipFileFill, + 0, + BufZipFileSkip, + BufZipFileClose); +} + +static int +BufZipFileClose(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 (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: + f->left = 0; + 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 (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(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; +} |