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authorDenis Vlasenko2007-03-14 00:06:29 +0000
committerDenis Vlasenko2007-03-14 00:06:29 +0000
commitda799e82274ffa48c5a27c5d034f4f31ba06e29f (patch)
tree9cc8813b722a7180b5545e31dfc5cf30631c4b1b /archival/gzip.c
parente930fe14413e0171d623010c4f7ff1152d58e8ab (diff)
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gzip: reduce global data footprint, part 2
Diffstat (limited to 'archival/gzip.c')
-rw-r--r--archival/gzip.c90
1 files changed, 46 insertions, 44 deletions
diff --git a/archival/gzip.c b/archival/gzip.c
index aa88fd7..76ee1cf 100644
--- a/archival/gzip.c
+++ b/archival/gzip.c
@@ -197,6 +197,9 @@ typedef int32_t lng;
typedef ush Pos;
typedef unsigned IPos;
+/* A Pos is an index in the character window. We use short instead of int to
+ * save space in the various tables. IPos is used only for parameter passing.
+ */
enum {
WINDOW_SIZE = 2 * WSIZE,
@@ -238,11 +241,8 @@ enum {
};
-struct G1 {
+struct global1 {
-/* A Pos is an index in the character window. We use short instead of int to
- * save space in the various tables. IPos is used only for parameter passing.
- */
lng block_start;
/* window position at the beginning of the current output block. Gets
@@ -266,7 +266,6 @@ struct G1 {
unsigned strstart; /* start of string to insert */
unsigned match_start; /* start of matching string */
unsigned lookahead; /* number of valid bytes ahead in window */
- smallint eofile; /* flag set at end of input file */
/* ===========================================================================
*/
@@ -318,6 +317,7 @@ struct G1 {
/* original time stamp (modification time) */
ulg time_stamp; /* only 32 bits stored in .gz file */
+//TODO: get rid of this
int ifd; /* input file descriptor */
int ofd; /* output file descriptor */
#ifdef DEBUG
@@ -325,8 +325,7 @@ struct G1 {
#endif
unsigned outcnt; /* bytes in output buffer */
- uint32_t *crc_32_tab;
-
+ smallint eofile; /* flag set at end of input file */
/* ===========================================================================
* Local data used by the "bit string" routines.
@@ -352,10 +351,12 @@ struct G1 {
ulg bits_sent; /* bit length of the compressed data */
#endif
+ uint32_t *crc_32_tab;
uint32_t crc; /* shift register contents */
};
-static struct G1 G1;
+extern struct global1 *global_ptr;
+#define G1 (*(global_ptr - 1))
/* ===========================================================================
@@ -880,7 +881,7 @@ typedef struct tree_desc {
int max_code; /* largest code with non zero frequency */
} tree_desc;
-struct G2 {
+struct global2 {
ush heap[HEAP_SIZE]; /* heap used to build the Huffman trees */
int heap_len; /* number of elements in the heap */
@@ -971,23 +972,8 @@ struct G2 {
};
-static struct G2 *G2ptr;
+#define G2ptr ((struct global2*)(global_ptr))
#define G2 (*G2ptr)
-/* {
- .l_desc = {
- G2.dyn_ltree, G2.static_ltree, extra_lbits,
- LITERALS + 1, L_CODES, MAX_BITS, 0
- },
- .d_desc = {
- G2.dyn_dtree, G2.static_dtree, extra_dbits,
- 0, D_CODES, MAX_BITS, 0
- },
- .bl_desc = {
- G2.bl_tree, NULL, extra_blbits,
- 0, BL_CODES, MAX_BL_BITS, 0
- }
-};
-*/
/* ===========================================================================
@@ -2045,7 +2031,7 @@ static void ct_init(void) ////ush * attr, int *methodp)
static void zip(int in, int out)
{
- uch my_flags = 0; /* general purpose bit flags */
+//// uch my_flags = 0; /* general purpose bit flags */
//// ush attr = 0; /* ascii/binary flag */
ush deflate_flags = 0; /* pkzip -es, -en or -ex equivalent */
//// int method = DEFLATED; /* compression method */
@@ -2056,11 +2042,15 @@ static void zip(int in, int out)
/* Write the header to the gzip file. See algorithm.doc for the format */
- put_header_byte(0x1f); /* magic header for gzip files, 1F 8B */
- put_header_byte(0x8b);
- ////put_header_byte(DEFLATED); /* compression method */
- put_header_byte(8); /* compression method */
- put_header_byte(my_flags); /* general flags */
+ //put_header_byte(0x1f); /* magic header for gzip files, 1F 8B */
+ //put_header_byte(0x8b);
+ //////put_header_byte(DEFLATED); /* compression method */
+ //put_header_byte(8); /* compression method */
+ //put_header_byte(0); /* general flags */
+ /* magic header for gzip files: 1F 8B */
+ /* compression method: 8 */
+ /* general flags: 0 */
+ put_32bit(0x00088b1f);
put_32bit(G1.time_stamp);
/* Write deflated file to zip file */
@@ -2141,19 +2131,31 @@ int gzip_main(int argc, char **argv)
}
#endif
- G2ptr = xzalloc(sizeof(*G2ptr));
- G2.l_desc = (tree_desc) {
- G2.dyn_ltree, G2.static_ltree, extra_lbits,
- LITERALS + 1, L_CODES, MAX_BITS, 0
- };
- G2.d_desc = (tree_desc) {
- G2.dyn_dtree, G2.static_dtree, extra_dbits,
- 0, D_CODES, MAX_BITS, 0
- };
- G2.bl_desc = (tree_desc) {
- G2.bl_tree, NULL, extra_blbits,
- 0, BL_CODES, MAX_BL_BITS, 0
- };
+ global_ptr = xzalloc(sizeof(struct global1) + sizeof(struct global2));
+ global_ptr++;
+ G2.l_desc.dyn_tree = G2.dyn_ltree;
+ G2.l_desc.static_tree = G2.static_ltree;
+ G2.l_desc.extra_bits = extra_lbits;
+ G2.l_desc.extra_base = LITERALS + 1;
+ G2.l_desc.elems = L_CODES;
+ G2.l_desc.max_length = MAX_BITS;
+ //G2.l_desc.max_code = 0;
+
+ G2.d_desc.dyn_tree = G2.dyn_dtree;
+ G2.d_desc.static_tree = G2.static_dtree;
+ G2.d_desc.extra_bits = extra_dbits;
+ //G2.d_desc.extra_base = 0;
+ G2.d_desc.elems = D_CODES;
+ G2.d_desc.max_length = MAX_BITS;
+ //G2.d_desc.max_code = 0;
+
+ G2.bl_desc.dyn_tree = G2.bl_tree;
+ //G2.bl_desc.static_tree = NULL;
+ G2.bl_desc.extra_bits = extra_blbits,
+ //G2.bl_desc.extra_base = 0;
+ G2.bl_desc.elems = BL_CODES;
+ G2.bl_desc.max_length = MAX_BL_BITS;
+ //G2.bl_desc.max_code = 0;
/* Allocate all global buffers (for DYN_ALLOC option) */
ALLOC(uch, G1.l_buf, INBUFSIZ);