aboutsummaryrefslogtreecommitdiff
path: root/lib/zlib_deflate
diff options
context:
space:
mode:
Diffstat (limited to 'lib/zlib_deflate')
-rw-r--r--lib/zlib_deflate/deflate.c31
-rw-r--r--lib/zlib_deflate/defutil.h17
2 files changed, 42 insertions, 6 deletions
diff --git a/lib/zlib_deflate/deflate.c b/lib/zlib_deflate/deflate.c
index 46a31e5f49c..d63381e8e33 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 6b15a909ca3..b640b6402e9 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.
*/