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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /lib/decompress_bunzip2.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to '')
-rw-r--r-- | lib/decompress_bunzip2.c | 756 |
1 files changed, 756 insertions, 0 deletions
diff --git a/lib/decompress_bunzip2.c b/lib/decompress_bunzip2.c new file mode 100644 index 000000000..3518e7394 --- /dev/null +++ b/lib/decompress_bunzip2.c @@ -0,0 +1,756 @@ +/* Small bzip2 deflate implementation, by Rob Landley (rob@landley.net). + + Based on bzip2 decompression code by Julian R Seward (jseward@acm.org), + which also acknowledges contributions by Mike Burrows, David Wheeler, + Peter Fenwick, Alistair Moffat, Radford Neal, Ian H. Witten, + Robert Sedgewick, and Jon L. Bentley. + + This code is licensed under the LGPLv2: + LGPL (http://www.gnu.org/copyleft/lgpl.html +*/ + +/* + Size and speed optimizations by Manuel Novoa III (mjn3@codepoet.org). + + More efficient reading of Huffman codes, a streamlined read_bunzip() + function, and various other tweaks. In (limited) tests, approximately + 20% faster than bzcat on x86 and about 10% faster on arm. + + Note that about 2/3 of the time is spent in read_unzip() reversing + the Burrows-Wheeler transformation. Much of that time is delay + resulting from cache misses. + + I would ask that anyone benefiting from this work, especially those + using it in commercial products, consider making a donation to my local + non-profit hospice organization in the name of the woman I loved, who + passed away Feb. 12, 2003. + + In memory of Toni W. Hagan + + Hospice of Acadiana, Inc. + 2600 Johnston St., Suite 200 + Lafayette, LA 70503-3240 + + Phone (337) 232-1234 or 1-800-738-2226 + Fax (337) 232-1297 + + https://www.hospiceacadiana.com/ + + Manuel + */ + +/* + Made it fit for running in Linux Kernel by Alain Knaff (alain@knaff.lu) +*/ + + +#ifdef STATIC +#define PREBOOT +#else +#include <linux/decompress/bunzip2.h> +#endif /* STATIC */ + +#include <linux/decompress/mm.h> +#include <linux/crc32poly.h> + +#ifndef INT_MAX +#define INT_MAX 0x7fffffff +#endif + +/* Constants for Huffman coding */ +#define MAX_GROUPS 6 +#define GROUP_SIZE 50 /* 64 would have been more efficient */ +#define MAX_HUFCODE_BITS 20 /* Longest Huffman code allowed */ +#define MAX_SYMBOLS 258 /* 256 literals + RUNA + RUNB */ +#define SYMBOL_RUNA 0 +#define SYMBOL_RUNB 1 + +/* Status return values */ +#define RETVAL_OK 0 +#define RETVAL_LAST_BLOCK (-1) +#define RETVAL_NOT_BZIP_DATA (-2) +#define RETVAL_UNEXPECTED_INPUT_EOF (-3) +#define RETVAL_UNEXPECTED_OUTPUT_EOF (-4) +#define RETVAL_DATA_ERROR (-5) +#define RETVAL_OUT_OF_MEMORY (-6) +#define RETVAL_OBSOLETE_INPUT (-7) + +/* Other housekeeping constants */ +#define BZIP2_IOBUF_SIZE 4096 + +/* This is what we know about each Huffman coding group */ +struct group_data { + /* We have an extra slot at the end of limit[] for a sentinel value. */ + int limit[MAX_HUFCODE_BITS+1]; + int base[MAX_HUFCODE_BITS]; + int permute[MAX_SYMBOLS]; + int minLen, maxLen; +}; + +/* Structure holding all the housekeeping data, including IO buffers and + memory that persists between calls to bunzip */ +struct bunzip_data { + /* State for interrupting output loop */ + int writeCopies, writePos, writeRunCountdown, writeCount, writeCurrent; + /* I/O tracking data (file handles, buffers, positions, etc.) */ + long (*fill)(void*, unsigned long); + long inbufCount, inbufPos /*, outbufPos*/; + unsigned char *inbuf /*,*outbuf*/; + unsigned int inbufBitCount, inbufBits; + /* The CRC values stored in the block header and calculated from the + data */ + unsigned int crc32Table[256], headerCRC, totalCRC, writeCRC; + /* Intermediate buffer and its size (in bytes) */ + unsigned int *dbuf, dbufSize; + /* These things are a bit too big to go on the stack */ + unsigned char selectors[32768]; /* nSelectors = 15 bits */ + struct group_data groups[MAX_GROUPS]; /* Huffman coding tables */ + int io_error; /* non-zero if we have IO error */ + int byteCount[256]; + unsigned char symToByte[256], mtfSymbol[256]; +}; + + +/* Return the next nnn bits of input. All reads from the compressed input + are done through this function. All reads are big endian */ +static unsigned int INIT get_bits(struct bunzip_data *bd, char bits_wanted) +{ + unsigned int bits = 0; + + /* If we need to get more data from the byte buffer, do so. + (Loop getting one byte at a time to enforce endianness and avoid + unaligned access.) */ + while (bd->inbufBitCount < bits_wanted) { + /* If we need to read more data from file into byte buffer, do + so */ + if (bd->inbufPos == bd->inbufCount) { + if (bd->io_error) + return 0; + bd->inbufCount = bd->fill(bd->inbuf, BZIP2_IOBUF_SIZE); + if (bd->inbufCount <= 0) { + bd->io_error = RETVAL_UNEXPECTED_INPUT_EOF; + return 0; + } + bd->inbufPos = 0; + } + /* Avoid 32-bit overflow (dump bit buffer to top of output) */ + if (bd->inbufBitCount >= 24) { + bits = bd->inbufBits&((1 << bd->inbufBitCount)-1); + bits_wanted -= bd->inbufBitCount; + bits <<= bits_wanted; + bd->inbufBitCount = 0; + } + /* Grab next 8 bits of input from buffer. */ + bd->inbufBits = (bd->inbufBits << 8)|bd->inbuf[bd->inbufPos++]; + bd->inbufBitCount += 8; + } + /* Calculate result */ + bd->inbufBitCount -= bits_wanted; + bits |= (bd->inbufBits >> bd->inbufBitCount)&((1 << bits_wanted)-1); + + return bits; +} + +/* Unpacks the next block and sets up for the inverse burrows-wheeler step. */ + +static int INIT get_next_block(struct bunzip_data *bd) +{ + struct group_data *hufGroup = NULL; + int *base = NULL; + int *limit = NULL; + int dbufCount, nextSym, dbufSize, groupCount, selector, + i, j, k, t, runPos, symCount, symTotal, nSelectors, *byteCount; + unsigned char uc, *symToByte, *mtfSymbol, *selectors; + unsigned int *dbuf, origPtr; + + dbuf = bd->dbuf; + dbufSize = bd->dbufSize; + selectors = bd->selectors; + byteCount = bd->byteCount; + symToByte = bd->symToByte; + mtfSymbol = bd->mtfSymbol; + + /* Read in header signature and CRC, then validate signature. + (last block signature means CRC is for whole file, return now) */ + i = get_bits(bd, 24); + j = get_bits(bd, 24); + bd->headerCRC = get_bits(bd, 32); + if ((i == 0x177245) && (j == 0x385090)) + return RETVAL_LAST_BLOCK; + if ((i != 0x314159) || (j != 0x265359)) + return RETVAL_NOT_BZIP_DATA; + /* We can add support for blockRandomised if anybody complains. + There was some code for this in busybox 1.0.0-pre3, but nobody ever + noticed that it didn't actually work. */ + if (get_bits(bd, 1)) + return RETVAL_OBSOLETE_INPUT; + origPtr = get_bits(bd, 24); + if (origPtr >= dbufSize) + return RETVAL_DATA_ERROR; + /* mapping table: if some byte values are never used (encoding things + like ascii text), the compression code removes the gaps to have fewer + symbols to deal with, and writes a sparse bitfield indicating which + values were present. We make a translation table to convert the + symbols back to the corresponding bytes. */ + t = get_bits(bd, 16); + symTotal = 0; + for (i = 0; i < 16; i++) { + if (t&(1 << (15-i))) { + k = get_bits(bd, 16); + for (j = 0; j < 16; j++) + if (k&(1 << (15-j))) + symToByte[symTotal++] = (16*i)+j; + } + } + /* How many different Huffman coding groups does this block use? */ + groupCount = get_bits(bd, 3); + if (groupCount < 2 || groupCount > MAX_GROUPS) + return RETVAL_DATA_ERROR; + /* nSelectors: Every GROUP_SIZE many symbols we select a new + Huffman coding group. Read in the group selector list, + which is stored as MTF encoded bit runs. (MTF = Move To + Front, as each value is used it's moved to the start of the + list.) */ + nSelectors = get_bits(bd, 15); + if (!nSelectors) + return RETVAL_DATA_ERROR; + for (i = 0; i < groupCount; i++) + mtfSymbol[i] = i; + for (i = 0; i < nSelectors; i++) { + /* Get next value */ + for (j = 0; get_bits(bd, 1); j++) + if (j >= groupCount) + return RETVAL_DATA_ERROR; + /* Decode MTF to get the next selector */ + uc = mtfSymbol[j]; + for (; j; j--) + mtfSymbol[j] = mtfSymbol[j-1]; + mtfSymbol[0] = selectors[i] = uc; + } + /* Read the Huffman coding tables for each group, which code + for symTotal literal symbols, plus two run symbols (RUNA, + RUNB) */ + symCount = symTotal+2; + for (j = 0; j < groupCount; j++) { + unsigned char length[MAX_SYMBOLS], temp[MAX_HUFCODE_BITS+1]; + int minLen, maxLen, pp; + /* Read Huffman code lengths for each symbol. They're + stored in a way similar to mtf; record a starting + value for the first symbol, and an offset from the + previous value for everys symbol after that. + (Subtracting 1 before the loop and then adding it + back at the end is an optimization that makes the + test inside the loop simpler: symbol length 0 + becomes negative, so an unsigned inequality catches + it.) */ + t = get_bits(bd, 5)-1; + for (i = 0; i < symCount; i++) { + for (;;) { + if (((unsigned)t) > (MAX_HUFCODE_BITS-1)) + return RETVAL_DATA_ERROR; + + /* If first bit is 0, stop. Else + second bit indicates whether to + increment or decrement the value. + Optimization: grab 2 bits and unget + the second if the first was 0. */ + + k = get_bits(bd, 2); + if (k < 2) { + bd->inbufBitCount++; + break; + } + /* Add one if second bit 1, else + * subtract 1. Avoids if/else */ + t += (((k+1)&2)-1); + } + /* Correct for the initial -1, to get the + * final symbol length */ + length[i] = t+1; + } + /* Find largest and smallest lengths in this group */ + minLen = maxLen = length[0]; + + for (i = 1; i < symCount; i++) { + if (length[i] > maxLen) + maxLen = length[i]; + else if (length[i] < minLen) + minLen = length[i]; + } + + /* Calculate permute[], base[], and limit[] tables from + * length[]. + * + * permute[] is the lookup table for converting + * Huffman coded symbols into decoded symbols. base[] + * is the amount to subtract from the value of a + * Huffman symbol of a given length when using + * permute[]. + * + * limit[] indicates the largest numerical value a + * symbol with a given number of bits can have. This + * is how the Huffman codes can vary in length: each + * code with a value > limit[length] needs another + * bit. + */ + hufGroup = bd->groups+j; + hufGroup->minLen = minLen; + hufGroup->maxLen = maxLen; + /* Note that minLen can't be smaller than 1, so we + adjust the base and limit array pointers so we're + not always wasting the first entry. We do this + again when using them (during symbol decoding).*/ + base = hufGroup->base-1; + limit = hufGroup->limit-1; + /* Calculate permute[]. Concurrently, initialize + * temp[] and limit[]. */ + pp = 0; + for (i = minLen; i <= maxLen; i++) { + temp[i] = limit[i] = 0; + for (t = 0; t < symCount; t++) + if (length[t] == i) + hufGroup->permute[pp++] = t; + } + /* Count symbols coded for at each bit length */ + for (i = 0; i < symCount; i++) + temp[length[i]]++; + /* Calculate limit[] (the largest symbol-coding value + *at each bit length, which is (previous limit << + *1)+symbols at this level), and base[] (number of + *symbols to ignore at each bit length, which is limit + *minus the cumulative count of symbols coded for + *already). */ + pp = t = 0; + for (i = minLen; i < maxLen; i++) { + pp += temp[i]; + /* We read the largest possible symbol size + and then unget bits after determining how + many we need, and those extra bits could be + set to anything. (They're noise from + future symbols.) At each level we're + really only interested in the first few + bits, so here we set all the trailing + to-be-ignored bits to 1 so they don't + affect the value > limit[length] + comparison. */ + limit[i] = (pp << (maxLen - i)) - 1; + pp <<= 1; + base[i+1] = pp-(t += temp[i]); + } + limit[maxLen+1] = INT_MAX; /* Sentinel value for + * reading next sym. */ + limit[maxLen] = pp+temp[maxLen]-1; + base[minLen] = 0; + } + /* We've finished reading and digesting the block header. Now + read this block's Huffman coded symbols from the file and + undo the Huffman coding and run length encoding, saving the + result into dbuf[dbufCount++] = uc */ + + /* Initialize symbol occurrence counters and symbol Move To + * Front table */ + for (i = 0; i < 256; i++) { + byteCount[i] = 0; + mtfSymbol[i] = (unsigned char)i; + } + /* Loop through compressed symbols. */ + runPos = dbufCount = symCount = selector = 0; + for (;;) { + /* Determine which Huffman coding group to use. */ + if (!(symCount--)) { + symCount = GROUP_SIZE-1; + if (selector >= nSelectors) + return RETVAL_DATA_ERROR; + hufGroup = bd->groups+selectors[selector++]; + base = hufGroup->base-1; + limit = hufGroup->limit-1; + } + /* Read next Huffman-coded symbol. */ + /* Note: It is far cheaper to read maxLen bits and + back up than it is to read minLen bits and then an + additional bit at a time, testing as we go. + Because there is a trailing last block (with file + CRC), there is no danger of the overread causing an + unexpected EOF for a valid compressed file. As a + further optimization, we do the read inline + (falling back to a call to get_bits if the buffer + runs dry). The following (up to got_huff_bits:) is + equivalent to j = get_bits(bd, hufGroup->maxLen); + */ + while (bd->inbufBitCount < hufGroup->maxLen) { + if (bd->inbufPos == bd->inbufCount) { + j = get_bits(bd, hufGroup->maxLen); + goto got_huff_bits; + } + bd->inbufBits = + (bd->inbufBits << 8)|bd->inbuf[bd->inbufPos++]; + bd->inbufBitCount += 8; + } + bd->inbufBitCount -= hufGroup->maxLen; + j = (bd->inbufBits >> bd->inbufBitCount)& + ((1 << hufGroup->maxLen)-1); +got_huff_bits: + /* Figure how many bits are in next symbol and + * unget extras */ + i = hufGroup->minLen; + while (j > limit[i]) + ++i; + bd->inbufBitCount += (hufGroup->maxLen - i); + /* Huffman decode value to get nextSym (with bounds checking) */ + if ((i > hufGroup->maxLen) + || (((unsigned)(j = (j>>(hufGroup->maxLen-i))-base[i])) + >= MAX_SYMBOLS)) + return RETVAL_DATA_ERROR; + nextSym = hufGroup->permute[j]; + /* We have now decoded the symbol, which indicates + either a new literal byte, or a repeated run of the + most recent literal byte. First, check if nextSym + indicates a repeated run, and if so loop collecting + how many times to repeat the last literal. */ + if (((unsigned)nextSym) <= SYMBOL_RUNB) { /* RUNA or RUNB */ + /* If this is the start of a new run, zero out + * counter */ + if (!runPos) { + runPos = 1; + t = 0; + } + /* Neat trick that saves 1 symbol: instead of + or-ing 0 or 1 at each bit position, add 1 + or 2 instead. For example, 1011 is 1 << 0 + + 1 << 1 + 2 << 2. 1010 is 2 << 0 + 2 << 1 + + 1 << 2. You can make any bit pattern + that way using 1 less symbol than the basic + or 0/1 method (except all bits 0, which + would use no symbols, but a run of length 0 + doesn't mean anything in this context). + Thus space is saved. */ + t += (runPos << nextSym); + /* +runPos if RUNA; +2*runPos if RUNB */ + + runPos <<= 1; + continue; + } + /* When we hit the first non-run symbol after a run, + we now know how many times to repeat the last + literal, so append that many copies to our buffer + of decoded symbols (dbuf) now. (The last literal + used is the one at the head of the mtfSymbol + array.) */ + if (runPos) { + runPos = 0; + if (dbufCount+t >= dbufSize) + return RETVAL_DATA_ERROR; + + uc = symToByte[mtfSymbol[0]]; + byteCount[uc] += t; + while (t--) + dbuf[dbufCount++] = uc; + } + /* Is this the terminating symbol? */ + if (nextSym > symTotal) + break; + /* At this point, nextSym indicates a new literal + character. Subtract one to get the position in the + MTF array at which this literal is currently to be + found. (Note that the result can't be -1 or 0, + because 0 and 1 are RUNA and RUNB. But another + instance of the first symbol in the mtf array, + position 0, would have been handled as part of a + run above. Therefore 1 unused mtf position minus 2 + non-literal nextSym values equals -1.) */ + if (dbufCount >= dbufSize) + return RETVAL_DATA_ERROR; + i = nextSym - 1; + uc = mtfSymbol[i]; + /* Adjust the MTF array. Since we typically expect to + *move only a small number of symbols, and are bound + *by 256 in any case, using memmove here would + *typically be bigger and slower due to function call + *overhead and other assorted setup costs. */ + do { + mtfSymbol[i] = mtfSymbol[i-1]; + } while (--i); + mtfSymbol[0] = uc; + uc = symToByte[uc]; + /* We have our literal byte. Save it into dbuf. */ + byteCount[uc]++; + dbuf[dbufCount++] = (unsigned int)uc; + } + /* At this point, we've read all the Huffman-coded symbols + (and repeated runs) for this block from the input stream, + and decoded them into the intermediate buffer. There are + dbufCount many decoded bytes in dbuf[]. Now undo the + Burrows-Wheeler transform on dbuf. See + http://dogma.net/markn/articles/bwt/bwt.htm + */ + /* Turn byteCount into cumulative occurrence counts of 0 to n-1. */ + j = 0; + for (i = 0; i < 256; i++) { + k = j+byteCount[i]; + byteCount[i] = j; + j = k; + } + /* Figure out what order dbuf would be in if we sorted it. */ + for (i = 0; i < dbufCount; i++) { + uc = (unsigned char)(dbuf[i] & 0xff); + dbuf[byteCount[uc]] |= (i << 8); + byteCount[uc]++; + } + /* Decode first byte by hand to initialize "previous" byte. + Note that it doesn't get output, and if the first three + characters are identical it doesn't qualify as a run (hence + writeRunCountdown = 5). */ + if (dbufCount) { + if (origPtr >= dbufCount) + return RETVAL_DATA_ERROR; + bd->writePos = dbuf[origPtr]; + bd->writeCurrent = (unsigned char)(bd->writePos&0xff); + bd->writePos >>= 8; + bd->writeRunCountdown = 5; + } + bd->writeCount = dbufCount; + + return RETVAL_OK; +} + +/* Undo burrows-wheeler transform on intermediate buffer to produce output. + If start_bunzip was initialized with out_fd =-1, then up to len bytes of + data are written to outbuf. Return value is number of bytes written or + error (all errors are negative numbers). If out_fd!=-1, outbuf and len + are ignored, data is written to out_fd and return is RETVAL_OK or error. +*/ + +static int INIT read_bunzip(struct bunzip_data *bd, char *outbuf, int len) +{ + const unsigned int *dbuf; + int pos, xcurrent, previous, gotcount; + + /* If last read was short due to end of file, return last block now */ + if (bd->writeCount < 0) + return bd->writeCount; + + gotcount = 0; + dbuf = bd->dbuf; + pos = bd->writePos; + xcurrent = bd->writeCurrent; + + /* We will always have pending decoded data to write into the output + buffer unless this is the very first call (in which case we haven't + Huffman-decoded a block into the intermediate buffer yet). */ + + if (bd->writeCopies) { + /* Inside the loop, writeCopies means extra copies (beyond 1) */ + --bd->writeCopies; + /* Loop outputting bytes */ + for (;;) { + /* If the output buffer is full, snapshot + * state and return */ + if (gotcount >= len) { + bd->writePos = pos; + bd->writeCurrent = xcurrent; + bd->writeCopies++; + return len; + } + /* Write next byte into output buffer, updating CRC */ + outbuf[gotcount++] = xcurrent; + bd->writeCRC = (((bd->writeCRC) << 8) + ^bd->crc32Table[((bd->writeCRC) >> 24) + ^xcurrent]); + /* Loop now if we're outputting multiple + * copies of this byte */ + if (bd->writeCopies) { + --bd->writeCopies; + continue; + } +decode_next_byte: + if (!bd->writeCount--) + break; + /* Follow sequence vector to undo + * Burrows-Wheeler transform */ + previous = xcurrent; + pos = dbuf[pos]; + xcurrent = pos&0xff; + pos >>= 8; + /* After 3 consecutive copies of the same + byte, the 4th is a repeat count. We count + down from 4 instead *of counting up because + testing for non-zero is faster */ + if (--bd->writeRunCountdown) { + if (xcurrent != previous) + bd->writeRunCountdown = 4; + } else { + /* We have a repeated run, this byte + * indicates the count */ + bd->writeCopies = xcurrent; + xcurrent = previous; + bd->writeRunCountdown = 5; + /* Sometimes there are just 3 bytes + * (run length 0) */ + if (!bd->writeCopies) + goto decode_next_byte; + /* Subtract the 1 copy we'd output + * anyway to get extras */ + --bd->writeCopies; + } + } + /* Decompression of this block completed successfully */ + bd->writeCRC = ~bd->writeCRC; + bd->totalCRC = ((bd->totalCRC << 1) | + (bd->totalCRC >> 31)) ^ bd->writeCRC; + /* If this block had a CRC error, force file level CRC error. */ + if (bd->writeCRC != bd->headerCRC) { + bd->totalCRC = bd->headerCRC+1; + return RETVAL_LAST_BLOCK; + } + } + + /* Refill the intermediate buffer by Huffman-decoding next + * block of input */ + /* (previous is just a convenient unused temp variable here) */ + previous = get_next_block(bd); + if (previous) { + bd->writeCount = previous; + return (previous != RETVAL_LAST_BLOCK) ? previous : gotcount; + } + bd->writeCRC = 0xffffffffUL; + pos = bd->writePos; + xcurrent = bd->writeCurrent; + goto decode_next_byte; +} + +static long INIT nofill(void *buf, unsigned long len) +{ + return -1; +} + +/* Allocate the structure, read file header. If in_fd ==-1, inbuf must contain + a complete bunzip file (len bytes long). If in_fd!=-1, inbuf and len are + ignored, and data is read from file handle into temporary buffer. */ +static int INIT start_bunzip(struct bunzip_data **bdp, void *inbuf, long len, + long (*fill)(void*, unsigned long)) +{ + struct bunzip_data *bd; + unsigned int i, j, c; + const unsigned int BZh0 = + (((unsigned int)'B') << 24)+(((unsigned int)'Z') << 16) + +(((unsigned int)'h') << 8)+(unsigned int)'0'; + + /* Figure out how much data to allocate */ + i = sizeof(struct bunzip_data); + + /* Allocate bunzip_data. Most fields initialize to zero. */ + bd = *bdp = malloc(i); + if (!bd) + return RETVAL_OUT_OF_MEMORY; + memset(bd, 0, sizeof(struct bunzip_data)); + /* Setup input buffer */ + bd->inbuf = inbuf; + bd->inbufCount = len; + if (fill != NULL) + bd->fill = fill; + else + bd->fill = nofill; + + /* Init the CRC32 table (big endian) */ + for (i = 0; i < 256; i++) { + c = i << 24; + for (j = 8; j; j--) + c = c&0x80000000 ? (c << 1)^(CRC32_POLY_BE) : (c << 1); + bd->crc32Table[i] = c; + } + + /* Ensure that file starts with "BZh['1'-'9']." */ + i = get_bits(bd, 32); + if (((unsigned int)(i-BZh0-1)) >= 9) + return RETVAL_NOT_BZIP_DATA; + + /* Fourth byte (ascii '1'-'9'), indicates block size in units of 100k of + uncompressed data. Allocate intermediate buffer for block. */ + bd->dbufSize = 100000*(i-BZh0); + + bd->dbuf = large_malloc(bd->dbufSize * sizeof(int)); + if (!bd->dbuf) + return RETVAL_OUT_OF_MEMORY; + return RETVAL_OK; +} + +/* Example usage: decompress src_fd to dst_fd. (Stops at end of bzip2 data, + not end of file.) */ +STATIC int INIT bunzip2(unsigned char *buf, long len, + long (*fill)(void*, unsigned long), + long (*flush)(void*, unsigned long), + unsigned char *outbuf, + long *pos, + void(*error)(char *x)) +{ + struct bunzip_data *bd; + int i = -1; + unsigned char *inbuf; + + if (flush) + outbuf = malloc(BZIP2_IOBUF_SIZE); + + if (!outbuf) { + error("Could not allocate output buffer"); + return RETVAL_OUT_OF_MEMORY; + } + if (buf) + inbuf = buf; + else + inbuf = malloc(BZIP2_IOBUF_SIZE); + if (!inbuf) { + error("Could not allocate input buffer"); + i = RETVAL_OUT_OF_MEMORY; + goto exit_0; + } + i = start_bunzip(&bd, inbuf, len, fill); + if (!i) { + for (;;) { + i = read_bunzip(bd, outbuf, BZIP2_IOBUF_SIZE); + if (i <= 0) + break; + if (!flush) + outbuf += i; + else + if (i != flush(outbuf, i)) { + i = RETVAL_UNEXPECTED_OUTPUT_EOF; + break; + } + } + } + /* Check CRC and release memory */ + if (i == RETVAL_LAST_BLOCK) { + if (bd->headerCRC != bd->totalCRC) + error("Data integrity error when decompressing."); + else + i = RETVAL_OK; + } else if (i == RETVAL_UNEXPECTED_OUTPUT_EOF) { + error("Compressed file ends unexpectedly"); + } + if (!bd) + goto exit_1; + if (bd->dbuf) + large_free(bd->dbuf); + if (pos) + *pos = bd->inbufPos; + free(bd); +exit_1: + if (!buf) + free(inbuf); +exit_0: + if (flush) + free(outbuf); + return i; +} + +#ifdef PREBOOT +STATIC int INIT __decompress(unsigned char *buf, long len, + long (*fill)(void*, unsigned long), + long (*flush)(void*, unsigned long), + unsigned char *outbuf, long olen, + long *pos, + void (*error)(char *x)) +{ + return bunzip2(buf, len - 4, fill, flush, outbuf, pos, error); +} +#endif |