diff options
Diffstat (limited to 'lib/zlib_dfltcc')
| -rw-r--r-- | lib/zlib_dfltcc/Makefile | 2 | ||||
| -rw-r--r-- | lib/zlib_dfltcc/dfltcc.h | 28 | ||||
| -rw-r--r-- | lib/zlib_dfltcc/dfltcc_inflate.c | 143 |
3 files changed, 172 insertions, 1 deletions
diff --git a/lib/zlib_dfltcc/Makefile b/lib/zlib_dfltcc/Makefile index 863d3b37e09d..8e4d5afbbb10 100644 --- a/lib/zlib_dfltcc/Makefile +++ b/lib/zlib_dfltcc/Makefile @@ -8,4 +8,4 @@ obj-$(CONFIG_ZLIB_DFLTCC) += zlib_dfltcc.o -zlib_dfltcc-objs := dfltcc.o dfltcc_deflate.o dfltcc_syms.o +zlib_dfltcc-objs := dfltcc.o dfltcc_deflate.o dfltcc_inflate.o dfltcc_syms.o diff --git a/lib/zlib_dfltcc/dfltcc.h b/lib/zlib_dfltcc/dfltcc.h index 18fed7a444bc..4782c92bb2ff 100644 --- a/lib/zlib_dfltcc/dfltcc.h +++ b/lib/zlib_dfltcc/dfltcc.h @@ -104,6 +104,14 @@ int dfltcc_deflate(z_streamp strm, int flush, block_state *result); void dfltcc_reset(z_streamp strm, uInt size); +int dfltcc_can_inflate(z_streamp strm); +typedef enum { + DFLTCC_INFLATE_CONTINUE, + DFLTCC_INFLATE_BREAK, + DFLTCC_INFLATE_SOFTWARE, +} dfltcc_inflate_action; +dfltcc_inflate_action dfltcc_inflate(z_streamp strm, + int flush, int *ret); #define DEFLATE_RESET_HOOK(strm) \ dfltcc_reset((strm), sizeof(deflate_state)) @@ -112,4 +120,24 @@ void dfltcc_reset(z_streamp strm, uInt size); #define DEFLATE_NEED_CHECKSUM(strm) (!dfltcc_can_deflate((strm))) +#define INFLATE_RESET_HOOK(strm) \ + dfltcc_reset((strm), sizeof(struct inflate_state)) + +#define INFLATE_TYPEDO_HOOK(strm, flush) \ + if (dfltcc_can_inflate((strm))) { \ + dfltcc_inflate_action action; \ +\ + RESTORE(); \ + action = dfltcc_inflate((strm), (flush), &ret); \ + LOAD(); \ + if (action == DFLTCC_INFLATE_CONTINUE) \ + break; \ + else if (action == DFLTCC_INFLATE_BREAK) \ + goto inf_leave; \ + } + +#define INFLATE_NEED_CHECKSUM(strm) (!dfltcc_can_inflate((strm))) + +#define INFLATE_NEED_UPDATEWINDOW(strm) (!dfltcc_can_inflate((strm))) + #endif /* DFLTCC_H */ diff --git a/lib/zlib_dfltcc/dfltcc_inflate.c b/lib/zlib_dfltcc/dfltcc_inflate.c new file mode 100644 index 000000000000..12a93a06bd61 --- /dev/null +++ b/lib/zlib_dfltcc/dfltcc_inflate.c @@ -0,0 +1,143 @@ +// SPDX-License-Identifier: Zlib + +#include "../zlib_inflate/inflate.h" +#include "dfltcc_util.h" +#include "dfltcc.h" +#include <linux/zutil.h> + +/* + * Expand. + */ +int dfltcc_can_inflate( + z_streamp strm +) +{ + struct inflate_state *state = (struct inflate_state *)strm->state; + struct dfltcc_state *dfltcc_state = GET_DFLTCC_STATE(state); + + /* Unsupported compression settings */ + if (state->wbits != HB_BITS) + return 0; + + /* Unsupported hardware */ + return is_bit_set(dfltcc_state->af.fns, DFLTCC_XPND) && + is_bit_set(dfltcc_state->af.fmts, DFLTCC_FMT0); +} + +static int dfltcc_was_inflate_used( + z_streamp strm +) +{ + struct inflate_state *state = (struct inflate_state *)strm->state; + struct dfltcc_param_v0 *param = &GET_DFLTCC_STATE(state)->param; + + return !param->nt; +} + +static int dfltcc_inflate_disable( + z_streamp strm +) +{ + struct inflate_state *state = (struct inflate_state *)strm->state; + struct dfltcc_state *dfltcc_state = GET_DFLTCC_STATE(state); + + if (!dfltcc_can_inflate(strm)) + return 0; + if (dfltcc_was_inflate_used(strm)) + /* DFLTCC has already decompressed some data. Since there is not + * enough information to resume decompression in software, the call + * must fail. + */ + return 1; + /* DFLTCC was not used yet - decompress in software */ + memset(&dfltcc_state->af, 0, sizeof(dfltcc_state->af)); + return 0; +} + +static dfltcc_cc dfltcc_xpnd( + z_streamp strm +) +{ + struct inflate_state *state = (struct inflate_state *)strm->state; + struct dfltcc_param_v0 *param = &GET_DFLTCC_STATE(state)->param; + size_t avail_in = strm->avail_in; + size_t avail_out = strm->avail_out; + dfltcc_cc cc; + + cc = dfltcc(DFLTCC_XPND | HBT_CIRCULAR, + param, &strm->next_out, &avail_out, + &strm->next_in, &avail_in, state->window); + strm->avail_in = avail_in; + strm->avail_out = avail_out; + return cc; +} + +dfltcc_inflate_action dfltcc_inflate( + z_streamp strm, + int flush, + int *ret +) +{ + struct inflate_state *state = (struct inflate_state *)strm->state; + struct dfltcc_state *dfltcc_state = GET_DFLTCC_STATE(state); + struct dfltcc_param_v0 *param = &dfltcc_state->param; + dfltcc_cc cc; + + if (flush == Z_BLOCK) { + /* DFLTCC does not support stopping on block boundaries */ + if (dfltcc_inflate_disable(strm)) { + *ret = Z_STREAM_ERROR; + return DFLTCC_INFLATE_BREAK; + } else + return DFLTCC_INFLATE_SOFTWARE; + } + + if (state->last) { + if (state->bits != 0) { + strm->next_in++; + strm->avail_in--; + state->bits = 0; + } + state->mode = CHECK; + return DFLTCC_INFLATE_CONTINUE; + } + + if (strm->avail_in == 0 && !param->cf) + return DFLTCC_INFLATE_BREAK; + + if (!state->window || state->wsize == 0) { + state->mode = MEM; + return DFLTCC_INFLATE_CONTINUE; + } + + /* Translate stream to parameter block */ + param->cvt = CVT_ADLER32; + param->sbb = state->bits; + param->hl = state->whave; /* Software and hardware history formats match */ + param->ho = (state->write - state->whave) & ((1 << HB_BITS) - 1); + if (param->hl) + param->nt = 0; /* Honor history for the first block */ + param->cv = state->flags ? REVERSE(state->check) : state->check; + + /* Inflate */ + do { + cc = dfltcc_xpnd(strm); + } while (cc == DFLTCC_CC_AGAIN); + + /* Translate parameter block to stream */ + strm->msg = oesc_msg(dfltcc_state->msg, param->oesc); + state->last = cc == DFLTCC_CC_OK; + state->bits = param->sbb; + state->whave = param->hl; + state->write = (param->ho + param->hl) & ((1 << HB_BITS) - 1); + state->check = state->flags ? REVERSE(param->cv) : param->cv; + if (cc == DFLTCC_CC_OP2_CORRUPT && param->oesc != 0) { + /* Report an error if stream is corrupted */ + state->mode = BAD; + return DFLTCC_INFLATE_CONTINUE; + } + state->mode = TYPEDO; + /* Break if operands are exhausted, otherwise continue looping */ + return (cc == DFLTCC_CC_OP1_TOO_SHORT || cc == DFLTCC_CC_OP2_TOO_SHORT) ? + DFLTCC_INFLATE_BREAK : DFLTCC_INFLATE_CONTINUE; +} |