diff options
Diffstat (limited to 'src/libflate/inflatezlib.c')
-rw-r--r-- | src/libflate/inflatezlib.c | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/src/libflate/inflatezlib.c b/src/libflate/inflatezlib.c new file mode 100644 index 00000000..3f31f10a --- /dev/null +++ b/src/libflate/inflatezlib.c @@ -0,0 +1,66 @@ +#include <u.h> +#include <libc.h> +#include <flate.h> +#include "zlib.h" + +typedef struct ZWrite ZWrite; + +struct ZWrite +{ + ulong adler; + void *wr; + int (*w)(void*, void*, int); +}; + +static int +zlwrite(void *vzw, void *buf, int n) +{ + ZWrite *zw; + + zw = vzw; + zw->adler = adler32(zw->adler, buf, n); + n = (*zw->w)(zw->wr, buf, n); + if(n <= 0) + return n; + return n; +} + +int +inflatezlib(void *wr, int (*w)(void*, void*, int), void *getr, int (*get)(void*)) +{ + ZWrite zw; + ulong v; + int c, i; + + c = (*get)(getr); + if(c < 0) + return FlateInputFail; + i = (*get)(getr); + if(i < 0) + return FlateInputFail; + + if(((c << 8) | i) % 31) + return FlateCorrupted; + if((c & ZlibMeth) != ZlibDeflate + || (c & ZlibCInfo) > ZlibWin32k) + return FlateCorrupted; + + zw.wr = wr; + zw.w = w; + zw.adler = 1; + i = inflate(&zw, zlwrite, getr, get); + if(i != FlateOk) + return i; + + v = 0; + for(i = 0; i < 4; i++){ + c = (*get)(getr); + if(c < 0) + return FlateInputFail; + v = (v << 8) | c; + } + if(zw.adler != v) + return FlateCorrupted; + + return FlateOk; +} |