X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=Xserver%2Flib%2Ffont%2Ffontfile%2Fgunzip.c;fp=Xserver%2Flib%2Ffont%2Ffontfile%2Fgunzip.c;h=6cf045a0714a043008415d153c249deb3c218ef3;hb=b6e6afccf37f4ad0515ef2a698f714fdf1bf23b3;hp=0000000000000000000000000000000000000000;hpb=e3340a110a3b01756b8e67531395a33b40a17d37;p=rdpsrv diff --git a/Xserver/lib/font/fontfile/gunzip.c b/Xserver/lib/font/fontfile/gunzip.c new file mode 100644 index 0000000..6cf045a --- /dev/null +++ b/Xserver/lib/font/fontfile/gunzip.c @@ -0,0 +1,224 @@ +/* $XConsortium: gunzip.c /main/1 1996/11/03 19:33:23 kaleb $ */ +/* lib/font/fontfile/gunzip.c + written by Mark Eichin September 1996. + intended for inclusion in X11 public releases. */ + +#include "fontmisc.h" +#include +#include + +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; +}