diff options
Diffstat (limited to 'lib/zlib_deflate')
| -rw-r--r-- | lib/zlib_deflate/deflate.c | 31 | ||||
| -rw-r--r-- | lib/zlib_deflate/defutil.h | 17 |
2 files changed, 42 insertions, 6 deletions
diff --git a/lib/zlib_deflate/deflate.c b/lib/zlib_deflate/deflate.c index 46a31e5f49c3..d63381e8e333 100644 --- a/lib/zlib_deflate/deflate.c +++ b/lib/zlib_deflate/deflate.c @@ -176,6 +176,7 @@ int zlib_deflateInit2( deflate_state *s; int noheader = 0; deflate_workspace *mem; + char *next; ush *overlay; /* We overlay pending_buf and d_buf+l_buf. This works since the average @@ -199,6 +200,21 @@ int zlib_deflateInit2( strategy < 0 || strategy > Z_HUFFMAN_ONLY) { return Z_STREAM_ERROR; } + + /* + * Direct the workspace's pointers to the chunks that were allocated + * along with the deflate_workspace struct. + */ + next = (char *) mem; + next += sizeof(*mem); + mem->window_memory = (Byte *) next; + next += zlib_deflate_window_memsize(windowBits); + mem->prev_memory = (Pos *) next; + next += zlib_deflate_prev_memsize(windowBits); + mem->head_memory = (Pos *) next; + next += zlib_deflate_head_memsize(memLevel); + mem->overlay_memory = next; + s = (deflate_state *) &(mem->deflate_memory); strm->state = (struct internal_state *)s; s->strm = strm; @@ -1247,7 +1263,18 @@ static block_state deflate_slow( return flush == Z_FINISH ? finish_done : block_done; } -int zlib_deflate_workspacesize(void) +int zlib_deflate_workspacesize(int windowBits, int memLevel) { - return sizeof(deflate_workspace); + if (windowBits < 0) /* undocumented feature: suppress zlib header */ + windowBits = -windowBits; + + /* Since the return value is typically passed to vmalloc() unchecked... */ + BUG_ON(memLevel < 1 || memLevel > MAX_MEM_LEVEL || windowBits < 9 || + windowBits > 15); + + return sizeof(deflate_workspace) + + zlib_deflate_window_memsize(windowBits) + + zlib_deflate_prev_memsize(windowBits) + + zlib_deflate_head_memsize(memLevel) + + zlib_deflate_overlay_memsize(memLevel); } diff --git a/lib/zlib_deflate/defutil.h b/lib/zlib_deflate/defutil.h index 6b15a909ca3f..b640b6402e99 100644 --- a/lib/zlib_deflate/defutil.h +++ b/lib/zlib_deflate/defutil.h @@ -241,12 +241,21 @@ typedef struct deflate_state { typedef struct deflate_workspace { /* State memory for the deflator */ deflate_state deflate_memory; - Byte window_memory[2 * (1 << MAX_WBITS)]; - Pos prev_memory[1 << MAX_WBITS]; - Pos head_memory[1 << (MAX_MEM_LEVEL + 7)]; - char overlay_memory[(1 << (MAX_MEM_LEVEL + 6)) * (sizeof(ush)+2)]; + Byte *window_memory; + Pos *prev_memory; + Pos *head_memory; + char *overlay_memory; } deflate_workspace; +#define zlib_deflate_window_memsize(windowBits) \ + (2 * (1 << (windowBits)) * sizeof(Byte)) +#define zlib_deflate_prev_memsize(windowBits) \ + ((1 << (windowBits)) * sizeof(Pos)) +#define zlib_deflate_head_memsize(memLevel) \ + ((1 << ((memLevel)+7)) * sizeof(Pos)) +#define zlib_deflate_overlay_memsize(memLevel) \ + ((1 << ((memLevel)+6)) * (sizeof(ush)+2)) + /* Output a byte on the stream. * IN assertion: there is enough room in pending_buf. */ |