diff options
Diffstat (limited to 'fs/jffs2/compr_rubin.c')
-rw-r--r-- | fs/jffs2/compr_rubin.c | 120 |
1 files changed, 64 insertions, 56 deletions
diff --git a/fs/jffs2/compr_rubin.c b/fs/jffs2/compr_rubin.c index c73fa89..170d289 100644 --- a/fs/jffs2/compr_rubin.c +++ b/fs/jffs2/compr_rubin.c @@ -22,9 +22,7 @@ #define BIT_DIVIDER_MIPS 1043 -static int bits_mips[8] = { 277,249,290,267,229,341,212,241}; /* mips32 */ - -#include <linux/errno.h> +static int bits_mips[8] = { 277, 249, 290, 267, 229, 341, 212, 241}; struct pushpull { unsigned char *buf; @@ -43,7 +41,9 @@ struct rubin_state { int bits[8]; }; -static inline void init_pushpull(struct pushpull *pp, char *buf, unsigned buflen, unsigned ofs, unsigned reserve) +static inline void init_pushpull(struct pushpull *pp, char *buf, + unsigned buflen, unsigned ofs, + unsigned reserve) { pp->buf = buf; pp->buflen = buflen; @@ -53,16 +53,14 @@ static inline void init_pushpull(struct pushpull *pp, char *buf, unsigned buflen static inline int pushbit(struct pushpull *pp, int bit, int use_reserved) { - if (pp->ofs >= pp->buflen - (use_reserved?0:pp->reserve)) { + if (pp->ofs >= pp->buflen - (use_reserved?0:pp->reserve)) return -ENOSPC; - } - if (bit) { - pp->buf[pp->ofs >> 3] |= (1<<(7-(pp->ofs &7))); - } - else { - pp->buf[pp->ofs >> 3] &= ~(1<<(7-(pp->ofs &7))); - } + if (bit) + pp->buf[pp->ofs >> 3] |= (1<<(7-(pp->ofs & 7))); + else + pp->buf[pp->ofs >> 3] &= ~(1<<(7-(pp->ofs & 7))); + pp->ofs++; return 0; @@ -97,6 +95,7 @@ static void init_rubin(struct rubin_state *rs, int div, int *bits) rs->p = (long) (2 * UPPER_BIT_RUBIN); rs->bit_number = (long) 0; rs->bit_divider = div; + for (c=0; c<8; c++) rs->bits[c] = bits[c]; } @@ -108,7 +107,8 @@ static int encode(struct rubin_state *rs, long A, long B, int symbol) long i0, i1; int ret; - while ((rs->q >= UPPER_BIT_RUBIN) || ((rs->p + rs->q) <= UPPER_BIT_RUBIN)) { + while ((rs->q >= UPPER_BIT_RUBIN) || + ((rs->p + rs->q) <= UPPER_BIT_RUBIN)) { rs->bit_number++; ret = pushbit(&rs->pp, (rs->q & UPPER_BIT_RUBIN) ? 1 : 0, 0); @@ -119,12 +119,12 @@ static int encode(struct rubin_state *rs, long A, long B, int symbol) rs->p <<= 1; } i0 = A * rs->p / (A + B); - if (i0 <= 0) { + if (i0 <= 0) i0 = 1; - } - if (i0 >= rs->p) { + + if (i0 >= rs->p) i0 = rs->p - 1; - } + i1 = rs->p - i0; if (symbol == 0) @@ -157,11 +157,13 @@ static void init_decode(struct rubin_state *rs, int div, int *bits) /* behalve lower */ rs->rec_q = 0; - for (rs->bit_number = 0; rs->bit_number++ < RUBIN_REG_SIZE; rs->rec_q = rs->rec_q * 2 + (long) (pullbit(&rs->pp))) + for (rs->bit_number = 0; rs->bit_number++ < RUBIN_REG_SIZE; + rs->rec_q = rs->rec_q * 2 + (long) (pullbit(&rs->pp))) ; } -static void __do_decode(struct rubin_state *rs, unsigned long p, unsigned long q) +static void __do_decode(struct rubin_state *rs, unsigned long p, + unsigned long q) { register unsigned long lower_bits_rubin = LOWER_BITS_RUBIN; unsigned long rec_q; @@ -207,12 +209,11 @@ static int decode(struct rubin_state *rs, long A, long B) __do_decode(rs, p, q); i0 = A * rs->p / (A + B); - if (i0 <= 0) { + if (i0 <= 0) i0 = 1; - } - if (i0 >= rs->p) { + + if (i0 >= rs->p) i0 = rs->p - 1; - } threshold = rs->q + i0; symbol = rs->rec_q >= threshold; @@ -234,14 +235,15 @@ static int out_byte(struct rubin_state *rs, unsigned char byte) struct rubin_state rs_copy; rs_copy = *rs; - for (i=0;i<8;i++) { - ret = encode(rs, rs->bit_divider-rs->bits[i],rs->bits[i],byte&1); + for (i=0; i<8; i++) { + ret = encode(rs, rs->bit_divider-rs->bits[i], + rs->bits[i], byte & 1); if (ret) { /* Failed. Restore old state */ *rs = rs_copy; return ret; } - byte=byte>>1; + byte >>= 1 ; } return 0; } @@ -251,7 +253,8 @@ static int in_byte(struct rubin_state *rs) int i, result = 0, bit_divider = rs->bit_divider; for (i = 0; i < 8; i++) - result |= decode(rs, bit_divider - rs->bits[i], rs->bits[i]) << i; + result |= decode(rs, bit_divider - rs->bits[i], + rs->bits[i]) << i; return result; } @@ -259,7 +262,8 @@ static int in_byte(struct rubin_state *rs) static int rubin_do_compress(int bit_divider, int *bits, unsigned char *data_in, - unsigned char *cpage_out, uint32_t *sourcelen, uint32_t *dstlen) + unsigned char *cpage_out, uint32_t *sourcelen, + uint32_t *dstlen) { int outpos = 0; int pos=0; @@ -295,7 +299,8 @@ static int rubin_do_compress(int bit_divider, int *bits, unsigned char *data_in, int jffs2_rubinmips_compress(unsigned char *data_in, unsigned char *cpage_out, uint32_t *sourcelen, uint32_t *dstlen, void *model) { - return rubin_do_compress(BIT_DIVIDER_MIPS, bits_mips, data_in, cpage_out, sourcelen, dstlen); + return rubin_do_compress(BIT_DIVIDER_MIPS, bits_mips, data_in, + cpage_out, sourcelen, dstlen); } #endif static int jffs2_dynrubin_compress(unsigned char *data_in, @@ -316,9 +321,8 @@ static int jffs2_dynrubin_compress(unsigned char *data_in, return -1; memset(histo, 0, 256); - for (i=0; i<mysrclen; i++) { + for (i=0; i<mysrclen; i++) histo[data_in[i]]++; - } memset(bits, 0, sizeof(int)*8); for (i=0; i<256; i++) { if (i&128) @@ -346,7 +350,8 @@ static int jffs2_dynrubin_compress(unsigned char *data_in, cpage_out[i] = bits[i]; } - ret = rubin_do_compress(256, bits, data_in, cpage_out+8, &mysrclen, &mydstlen); + ret = rubin_do_compress(256, bits, data_in, cpage_out+8, &mysrclen, + &mydstlen); if (ret) return ret; @@ -363,8 +368,10 @@ static int jffs2_dynrubin_compress(unsigned char *data_in, return 0; } -static void rubin_do_decompress(int bit_divider, int *bits, unsigned char *cdata_in, - unsigned char *page_out, uint32_t srclen, uint32_t destlen) +static void rubin_do_decompress(int bit_divider, int *bits, + unsigned char *cdata_in, + unsigned char *page_out, uint32_t srclen, + uint32_t destlen) { int outpos = 0; struct rubin_state rs; @@ -372,9 +379,8 @@ static void rubin_do_decompress(int bit_divider, int *bits, unsigned char *cdata init_pushpull(&rs.pp, cdata_in, srclen, 0, 0); init_decode(&rs, bit_divider, bits); - while (outpos < destlen) { + while (outpos < destlen) page_out[outpos++] = in_byte(&rs); - } } @@ -383,7 +389,8 @@ static int jffs2_rubinmips_decompress(unsigned char *data_in, uint32_t sourcelen, uint32_t dstlen, void *model) { - rubin_do_decompress(BIT_DIVIDER_MIPS, bits_mips, data_in, cpage_out, sourcelen, dstlen); + rubin_do_decompress(BIT_DIVIDER_MIPS, bits_mips, data_in, + cpage_out, sourcelen, dstlen); return 0; } @@ -398,52 +405,53 @@ static int jffs2_dynrubin_decompress(unsigned char *data_in, for (c=0; c<8; c++) bits[c] = data_in[c]; - rubin_do_decompress(256, bits, data_in+8, cpage_out, sourcelen-8, dstlen); + rubin_do_decompress(256, bits, data_in+8, cpage_out, sourcelen-8, + dstlen); return 0; } static struct jffs2_compressor jffs2_rubinmips_comp = { - .priority = JFFS2_RUBINMIPS_PRIORITY, - .name = "rubinmips", - .compr = JFFS2_COMPR_DYNRUBIN, - .compress = NULL, /*&jffs2_rubinmips_compress,*/ - .decompress = &jffs2_rubinmips_decompress, + .priority = JFFS2_RUBINMIPS_PRIORITY, + .name = "rubinmips", + .compr = JFFS2_COMPR_DYNRUBIN, + .compress = NULL, /*&jffs2_rubinmips_compress,*/ + .decompress = &jffs2_rubinmips_decompress, #ifdef JFFS2_RUBINMIPS_DISABLED - .disabled = 1, + .disabled = 1, #else - .disabled = 0, + .disabled = 0, #endif }; int jffs2_rubinmips_init(void) { - return jffs2_register_compressor(&jffs2_rubinmips_comp); + return jffs2_register_compressor(&jffs2_rubinmips_comp); } void jffs2_rubinmips_exit(void) { - jffs2_unregister_compressor(&jffs2_rubinmips_comp); + jffs2_unregister_compressor(&jffs2_rubinmips_comp); } static struct jffs2_compressor jffs2_dynrubin_comp = { - .priority = JFFS2_DYNRUBIN_PRIORITY, - .name = "dynrubin", - .compr = JFFS2_COMPR_RUBINMIPS, - .compress = jffs2_dynrubin_compress, - .decompress = &jffs2_dynrubin_decompress, + .priority = JFFS2_DYNRUBIN_PRIORITY, + .name = "dynrubin", + .compr = JFFS2_COMPR_RUBINMIPS, + .compress = jffs2_dynrubin_compress, + .decompress = &jffs2_dynrubin_decompress, #ifdef JFFS2_DYNRUBIN_DISABLED - .disabled = 1, + .disabled = 1, #else - .disabled = 0, + .disabled = 0, #endif }; int jffs2_dynrubin_init(void) { - return jffs2_register_compressor(&jffs2_dynrubin_comp); + return jffs2_register_compressor(&jffs2_dynrubin_comp); } void jffs2_dynrubin_exit(void) { - jffs2_unregister_compressor(&jffs2_dynrubin_comp); + jffs2_unregister_compressor(&jffs2_dynrubin_comp); } |