From da799e82274ffa48c5a27c5d034f4f31ba06e29f Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Wed, 14 Mar 2007 00:06:29 +0000 Subject: gzip: reduce global data footprint, part 2 --- archival/gzip.c | 90 +++++++++++++++++++++++++++++---------------------------- 1 file changed, 46 insertions(+), 44 deletions(-) (limited to 'archival/gzip.c') diff --git a/archival/gzip.c b/archival/gzip.c index aa88fd7e5..76ee1cf58 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); -- cgit v1.2.3