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authorclick <none@none>2010-06-06 00:33:59 +0200
committerclick <none@none>2010-06-06 00:33:59 +0200
commit57dfe20206cd5e0119ac51908a27243cf40aa403 (patch)
treeaf92c87aaad4ffec7e0bc42afed6b3fe26f717a2 /dep/src/libmpq/explode.c
parent75b80d9f5b02a643c983b2fb1ededed79fd5d133 (diff)
Kick libmpq includes and sourcefiles into shape
--HG-- branch : trunk rename : dep/libmpq/libmpq/common.h => dep/include/libmpq/common.h rename : dep/libmpq/libmpq/crypt_buf.h => dep/include/libmpq/crypt_buf.h rename : dep/libmpq/libmpq/explode.h => dep/include/libmpq/explode.h rename : dep/libmpq/libmpq/extract.h => dep/include/libmpq/extract.h rename : dep/libmpq/libmpq/huffman.h => dep/include/libmpq/huffman.h rename : dep/libmpq/libmpq/mpq-internal.h => dep/include/libmpq/mpq-internal.h rename : dep/libmpq/libmpq/mpq.h => dep/include/libmpq/mpq.h rename : dep/libmpq/libmpq/wave.h => dep/include/libmpq/wave.h rename : dep/libmpq/libmpq/common.c => dep/src/libmpq/common.c rename : dep/libmpq/libmpq/explode.c => dep/src/libmpq/explode.c rename : dep/libmpq/libmpq/extract.c => dep/src/libmpq/extract.c rename : dep/libmpq/libmpq/huffman.c => dep/src/libmpq/huffman.c rename : dep/libmpq/libmpq/mpq.c => dep/src/libmpq/mpq.c rename : dep/libmpq/libmpq/wave.c => dep/src/libmpq/wave.c
Diffstat (limited to 'dep/src/libmpq/explode.c')
-rw-r--r--dep/src/libmpq/explode.c602
1 files changed, 602 insertions, 0 deletions
diff --git a/dep/src/libmpq/explode.c b/dep/src/libmpq/explode.c
new file mode 100644
index 00000000000..2d778d25c39
--- /dev/null
+++ b/dep/src/libmpq/explode.c
@@ -0,0 +1,602 @@
+/*
+ * explode.c -- explode function of pkware data compression library.
+ *
+ * Copyright (c) 2003-2008 Maik Broemme <mbroemme@plusserver.de>
+ *
+ * This source was adepted from the C++ version of pkware.cpp included
+ * in stormlib. The C++ version belongs to the following authors:
+ *
+ * Ladislav Zezula <ladik@zezula.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+/* generic includes. */
+#include <string.h>
+
+/* libmpq main includes. */
+#include "mpq.h"
+
+/* libmpq generic includes. */
+#include "explode.h"
+
+/* tables used for data extraction. */
+static const uint8_t pkzip_dist_bits[] = {
+ 0x02, 0x04, 0x04, 0x05, 0x05, 0x05, 0x05, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x06,
+ 0x06, 0x06, 0x06, 0x06, 0x06, 0x06, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
+ 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08
+};
+
+/* tables used for data extraction. */
+static const uint8_t pkzip_dist_code[] = {
+ 0x03, 0x0D, 0x05, 0x19, 0x09, 0x11, 0x01, 0x3E, 0x1E, 0x2E, 0x0E, 0x36, 0x16, 0x26, 0x06, 0x3A,
+ 0x1A, 0x2A, 0x0A, 0x32, 0x12, 0x22, 0x42, 0x02, 0x7C, 0x3C, 0x5C, 0x1C, 0x6C, 0x2C, 0x4C, 0x0C,
+ 0x74, 0x34, 0x54, 0x14, 0x64, 0x24, 0x44, 0x04, 0x78, 0x38, 0x58, 0x18, 0x68, 0x28, 0x48, 0x08,
+ 0xF0, 0x70, 0xB0, 0x30, 0xD0, 0x50, 0x90, 0x10, 0xE0, 0x60, 0xA0, 0x20, 0xC0, 0x40, 0x80, 0x00
+};
+
+/* tables used for data extraction. */
+static const uint8_t pkzip_clen_bits[] = {
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08
+};
+
+/* tables used for data extraction. */
+static const uint16_t pkzip_len_base[] = {
+ 0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x0007,
+ 0x0008, 0x000A, 0x000E, 0x0016, 0x0026, 0x0046, 0x0086, 0x0106
+};
+
+/* tables used for data extraction. */
+static const uint8_t pkzip_slen_bits[] = {
+ 0x03, 0x02, 0x03, 0x03, 0x04, 0x04, 0x04, 0x05, 0x05, 0x05, 0x05, 0x06, 0x06, 0x06, 0x07, 0x07
+};
+
+/* tables used for data extraction. */
+static const uint8_t pkzip_len_code[] = {
+ 0x05, 0x03, 0x01, 0x06, 0x0A, 0x02, 0x0C, 0x14, 0x04, 0x18, 0x08, 0x30, 0x10, 0x20, 0x40, 0x00
+};
+
+/* tables used for data extraction. */
+static const uint8_t pkzip_bits_asc[] = {
+ 0x0B, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x08, 0x07, 0x0C, 0x0C, 0x07, 0x0C, 0x0C,
+ 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0D, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C,
+ 0x04, 0x0A, 0x08, 0x0C, 0x0A, 0x0C, 0x0A, 0x08, 0x07, 0x07, 0x08, 0x09, 0x07, 0x06, 0x07, 0x08,
+ 0x07, 0x06, 0x07, 0x07, 0x07, 0x07, 0x08, 0x07, 0x07, 0x08, 0x08, 0x0C, 0x0B, 0x07, 0x09, 0x0B,
+ 0x0C, 0x06, 0x07, 0x06, 0x06, 0x05, 0x07, 0x08, 0x08, 0x06, 0x0B, 0x09, 0x06, 0x07, 0x06, 0x06,
+ 0x07, 0x0B, 0x06, 0x06, 0x06, 0x07, 0x09, 0x08, 0x09, 0x09, 0x0B, 0x08, 0x0B, 0x09, 0x0C, 0x08,
+ 0x0C, 0x05, 0x06, 0x06, 0x06, 0x05, 0x06, 0x06, 0x06, 0x05, 0x0B, 0x07, 0x05, 0x06, 0x05, 0x05,
+ 0x06, 0x0A, 0x05, 0x05, 0x05, 0x05, 0x08, 0x07, 0x08, 0x08, 0x0A, 0x0B, 0x0B, 0x0C, 0x0C, 0x0C,
+ 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D,
+ 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D,
+ 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D,
+ 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C,
+ 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C,
+ 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C,
+ 0x0D, 0x0C, 0x0D, 0x0D, 0x0D, 0x0C, 0x0D, 0x0D, 0x0D, 0x0C, 0x0D, 0x0D, 0x0D, 0x0D, 0x0C, 0x0D,
+ 0x0D, 0x0D, 0x0C, 0x0C, 0x0C, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D, 0x0D
+};
+
+/* tables used for data extraction. */
+static const uint16_t pkzip_code_asc[] = {
+ 0x0490, 0x0FE0, 0x07E0, 0x0BE0, 0x03E0, 0x0DE0, 0x05E0, 0x09E0,
+ 0x01E0, 0x00B8, 0x0062, 0x0EE0, 0x06E0, 0x0022, 0x0AE0, 0x02E0,
+ 0x0CE0, 0x04E0, 0x08E0, 0x00E0, 0x0F60, 0x0760, 0x0B60, 0x0360,
+ 0x0D60, 0x0560, 0x1240, 0x0960, 0x0160, 0x0E60, 0x0660, 0x0A60,
+ 0x000F, 0x0250, 0x0038, 0x0260, 0x0050, 0x0C60, 0x0390, 0x00D8,
+ 0x0042, 0x0002, 0x0058, 0x01B0, 0x007C, 0x0029, 0x003C, 0x0098,
+ 0x005C, 0x0009, 0x001C, 0x006C, 0x002C, 0x004C, 0x0018, 0x000C,
+ 0x0074, 0x00E8, 0x0068, 0x0460, 0x0090, 0x0034, 0x00B0, 0x0710,
+ 0x0860, 0x0031, 0x0054, 0x0011, 0x0021, 0x0017, 0x0014, 0x00A8,
+ 0x0028, 0x0001, 0x0310, 0x0130, 0x003E, 0x0064, 0x001E, 0x002E,
+ 0x0024, 0x0510, 0x000E, 0x0036, 0x0016, 0x0044, 0x0030, 0x00C8,
+ 0x01D0, 0x00D0, 0x0110, 0x0048, 0x0610, 0x0150, 0x0060, 0x0088,
+ 0x0FA0, 0x0007, 0x0026, 0x0006, 0x003A, 0x001B, 0x001A, 0x002A,
+ 0x000A, 0x000B, 0x0210, 0x0004, 0x0013, 0x0032, 0x0003, 0x001D,
+ 0x0012, 0x0190, 0x000D, 0x0015, 0x0005, 0x0019, 0x0008, 0x0078,
+ 0x00F0, 0x0070, 0x0290, 0x0410, 0x0010, 0x07A0, 0x0BA0, 0x03A0,
+ 0x0240, 0x1C40, 0x0C40, 0x1440, 0x0440, 0x1840, 0x0840, 0x1040,
+ 0x0040, 0x1F80, 0x0F80, 0x1780, 0x0780, 0x1B80, 0x0B80, 0x1380,
+ 0x0380, 0x1D80, 0x0D80, 0x1580, 0x0580, 0x1980, 0x0980, 0x1180,
+ 0x0180, 0x1E80, 0x0E80, 0x1680, 0x0680, 0x1A80, 0x0A80, 0x1280,
+ 0x0280, 0x1C80, 0x0C80, 0x1480, 0x0480, 0x1880, 0x0880, 0x1080,
+ 0x0080, 0x1F00, 0x0F00, 0x1700, 0x0700, 0x1B00, 0x0B00, 0x1300,
+ 0x0DA0, 0x05A0, 0x09A0, 0x01A0, 0x0EA0, 0x06A0, 0x0AA0, 0x02A0,
+ 0x0CA0, 0x04A0, 0x08A0, 0x00A0, 0x0F20, 0x0720, 0x0B20, 0x0320,
+ 0x0D20, 0x0520, 0x0920, 0x0120, 0x0E20, 0x0620, 0x0A20, 0x0220,
+ 0x0C20, 0x0420, 0x0820, 0x0020, 0x0FC0, 0x07C0, 0x0BC0, 0x03C0,
+ 0x0DC0, 0x05C0, 0x09C0, 0x01C0, 0x0EC0, 0x06C0, 0x0AC0, 0x02C0,
+ 0x0CC0, 0x04C0, 0x08C0, 0x00C0, 0x0F40, 0x0740, 0x0B40, 0x0340,
+ 0x0300, 0x0D40, 0x1D00, 0x0D00, 0x1500, 0x0540, 0x0500, 0x1900,
+ 0x0900, 0x0940, 0x1100, 0x0100, 0x1E00, 0x0E00, 0x0140, 0x1600,
+ 0x0600, 0x1A00, 0x0E40, 0x0640, 0x0A40, 0x0A00, 0x1200, 0x0200,
+ 0x1C00, 0x0C00, 0x1400, 0x0400, 0x1800, 0x0800, 0x1000, 0x0000
+};
+
+/* local unused variables. */
+char pkware_copyright[] = "PKWARE Data Compression Library for Win32\r\n"
+ "Copyright 1989-1995 PKWARE Inc. All Rights Reserved\r\n"
+ "Patent No. 5,051,745\r\n"
+ "PKWARE Data Compression Library Reg. U.S. Pat. and Tm. Off.\r\n"
+ "Version 1.11\r\n";
+
+/* skips given number of bits. */
+static int32_t skip_bit(pkzip_cmp_s *mpq_pkzip, uint32_t bits) {
+
+ /* check if number of bits required is less than number of bits in the buffer. */
+ if (bits <= mpq_pkzip->extra_bits) {
+ mpq_pkzip->extra_bits -= bits;
+ mpq_pkzip->bit_buf >>= bits;
+ return 0;
+ }
+
+ /* load input buffer if necessary. */
+ mpq_pkzip->bit_buf >>= mpq_pkzip->extra_bits;
+ if (mpq_pkzip->in_pos == mpq_pkzip->in_bytes) {
+ mpq_pkzip->in_pos = sizeof(mpq_pkzip->in_buf);
+ if ((mpq_pkzip->in_bytes = mpq_pkzip->read_buf((char *)mpq_pkzip->in_buf, &mpq_pkzip->in_pos, mpq_pkzip->param)) == 0) {
+ return 1;
+ }
+ mpq_pkzip->in_pos = 0;
+ }
+
+ /* update bit buffer. */
+ mpq_pkzip->bit_buf |= (mpq_pkzip->in_buf[mpq_pkzip->in_pos++] << 8);
+ mpq_pkzip->bit_buf >>= (bits - mpq_pkzip->extra_bits);
+ mpq_pkzip->extra_bits = (mpq_pkzip->extra_bits - bits) + 8;
+
+ /* if no error was found, return zero. */
+ return 0;
+}
+
+/* this function generate the decode tables used for decryption. */
+static void generate_tables_decode(int32_t count, uint8_t *bits, const uint8_t *code, uint8_t *buf2) {
+
+ /* some common variables. */
+ int32_t i;
+
+ /* EBX - count */
+ for (i = count-1; i >= 0; i--) {
+
+ /* some common variables. */
+ uint32_t idx1 = code[i];
+ uint32_t idx2 = 1 << bits[i];
+
+ /* loop until table is ready. */
+ do {
+ buf2[idx1] = (uint8_t)i;
+ idx1 += idx2;
+ } while (idx1 < 0x100);
+ }
+}
+
+/* this function generate the tables for ascii decompression. */
+static void generate_tables_ascii(pkzip_cmp_s *mpq_pkzip) {
+
+ /* some common variables. */
+ const uint16_t *code_asc = &pkzip_code_asc[0xFF];
+ uint32_t acc;
+ uint32_t add;
+ uint16_t count;
+
+ /* loop through ascii table. */
+ for (count = 0x00FF; code_asc >= pkzip_code_asc; code_asc--, count--) {
+ uint8_t *bits_asc = mpq_pkzip->bits_asc + count;
+ uint8_t bits_tmp = *bits_asc;
+
+ /* check if byte is finished. */
+ if (bits_tmp <= 8) {
+ add = (1 << bits_tmp);
+ acc = *code_asc;
+ do {
+ mpq_pkzip->offs_2c34[acc] = (uint8_t)count;
+ acc += add;
+ } while (acc < 0x100);
+ } else {
+ if ((acc = (*code_asc & 0xFF)) != 0) {
+ mpq_pkzip->offs_2c34[acc] = 0xFF;
+ if (*code_asc & 0x3F) {
+
+ /* decrease bit by four. */
+ bits_tmp -= 4;
+ *bits_asc = bits_tmp;
+ add = (1 << bits_tmp);
+ acc = *code_asc >> 4;
+ do {
+ mpq_pkzip->offs_2d34[acc] = (uint8_t)count;
+ acc += add;
+ } while (acc < 0x100);
+ } else {
+
+ /* decrease bit by six. */
+ bits_tmp -= 6;
+ *bits_asc = bits_tmp;
+ add = (1 << bits_tmp);
+ acc = *code_asc >> 6;
+ do {
+ mpq_pkzip->offs_2e34[acc] = (uint8_t)count;
+ acc += add;
+ } while (acc < 0x80);
+ }
+ } else {
+
+ /* decrease bit by eight. (one byte) */
+ bits_tmp -= 8;
+ *bits_asc = bits_tmp;
+ add = (1 << bits_tmp);
+ acc = *code_asc >> 8;
+ do {
+ mpq_pkzip->offs_2eb4[acc] = (uint8_t)count;
+ acc += add;
+ } while (acc < 0x100);
+ }
+ }
+ }
+}
+
+/*
+ * decompress the imploded data using coded literals.
+ *
+ * returns: 0x000 - 0x0FF : one byte from compressed file.
+ * 0x100 - 0x305 : copy previous block. (0x100 = 1 byte)
+ * 0x306 : out of buffer?
+ */
+static uint32_t decode_literal(pkzip_cmp_s *mpq_pkzip) {
+
+ /* number of bits to skip. */
+ uint32_t bits;
+
+ /* position in buffers. */
+ uint32_t value;
+
+ /* check if bit the current buffer is set, if not return the next byte. */
+ if (mpq_pkzip->bit_buf & 1) {
+
+ /* skip current bit in the buffer. */
+ if (skip_bit(mpq_pkzip, 1)) {
+ return 0x306;
+ }
+
+ /* the next bits are position in buffers. */
+ value = mpq_pkzip->pos2[(mpq_pkzip->bit_buf & 0xFF)];
+
+ /* get number of bits to skip. */
+ if (skip_bit(mpq_pkzip, mpq_pkzip->slen_bits[value])) {
+ return 0x306;
+ }
+
+ /* check bits. */
+ if ((bits = mpq_pkzip->clen_bits[value]) != 0) {
+
+ /* some common variables. */
+ uint32_t val2 = mpq_pkzip->bit_buf & ((1 << bits) - 1);
+
+ /* check if we should skip one bit. */
+ if (skip_bit(mpq_pkzip, bits)) {
+
+ /* check position if we should skip the bit. */
+ if ((value + val2) != 0x10E) {
+ return 0x306;
+ }
+ }
+
+ /* fill values. */
+ value = mpq_pkzip->len_base[value] + val2;
+ }
+
+ /* return number of bytes to repeat. */
+ return value + 0x100;
+ }
+
+ /* skip one bit. */
+ if (skip_bit(mpq_pkzip, 1)) {
+ return 0x306;
+ }
+
+ /* check the binary compression type, read 8 bits and return them as one byte. */
+ if (mpq_pkzip->cmp_type == LIBMPQ_PKZIP_CMP_BINARY) {
+
+ /* fill values. */
+ value = mpq_pkzip->bit_buf & 0xFF;
+
+ /* check if we should skip one bit. */
+ if (skip_bit(mpq_pkzip, 8)) {
+ return 0x306;
+ }
+
+ /* return value from bit buffer. */
+ return value;
+ }
+
+ /* check if ascii compression is used. */
+ if (mpq_pkzip->bit_buf & 0xFF) {
+
+ /* fill values. */
+ value = mpq_pkzip->offs_2c34[mpq_pkzip->bit_buf & 0xFF];
+
+ /* check value. */
+ if (value == 0xFF) {
+ if (mpq_pkzip->bit_buf & 0x3F) {
+
+ /* check if four bits are in bit buffer for skipping. */
+ if (skip_bit(mpq_pkzip, 4)) {
+ return 0x306;
+ }
+
+ /* fill values. */
+ value = mpq_pkzip->offs_2d34[mpq_pkzip->bit_buf & 0xFF];
+ } else {
+
+ /* check if six bits are in bit buffer for skipping. */
+ if (skip_bit(mpq_pkzip, 6)) {
+ return 0x306;
+ }
+
+ /* fill values. */
+ value = mpq_pkzip->offs_2e34[mpq_pkzip->bit_buf & 0x7F];
+ }
+ }
+ } else {
+
+ /* check if eight bits are in bit buffer for skipping. */
+ if (skip_bit(mpq_pkzip, 8)) {
+ return 0x306;
+ }
+
+ /* fill values. */
+ value = mpq_pkzip->offs_2eb4[mpq_pkzip->bit_buf & 0xFF];
+ }
+
+ /* return out of buffer error (0x306) or position in buffer. */
+ return skip_bit(mpq_pkzip, mpq_pkzip->bits_asc[value]) ? 0x306 : value;
+}
+
+/* this function retrieves the number of bytes to move back. */
+static uint32_t decode_distance(pkzip_cmp_s *mpq_pkzip, uint32_t length) {
+
+ /* some common variables. */
+ uint32_t pos = mpq_pkzip->pos1[(mpq_pkzip->bit_buf & 0xFF)];
+
+ /* number of bits to skip. */
+ uint32_t skip = mpq_pkzip->dist_bits[pos];
+
+ /* skip the appropriate number of bits. */
+ if (skip_bit(mpq_pkzip, skip) == 1) {
+ return 0;
+ }
+
+ /* check if length is two. */
+ if (length == 2) {
+ pos = (pos << 2) | (mpq_pkzip->bit_buf & 0x03);
+
+ /* skip the bits. */
+ if (skip_bit(mpq_pkzip, 2) == 1) {
+ return 0;
+ }
+ } else {
+ pos = (pos << mpq_pkzip->dsize_bits) | (mpq_pkzip->bit_buf & mpq_pkzip->dsize_mask);
+
+ /* skip the bits */
+ if (skip_bit(mpq_pkzip, mpq_pkzip->dsize_bits) == 1) {
+ return 0;
+ }
+ }
+
+ /* return the bytes to move back. */
+ return pos + 1;
+}
+
+/*
+ * function loads data from the input buffer used by mpq_pkzip
+ * "implode" and "explode" function as user defined callback and
+ * returns number of bytes loaded.
+ *
+ * char *buf - pointer to a buffer where to store loaded data.
+ * uint32_t *size - maximum number of bytes to read.
+ * void *param - custom pointer, parameter of implode/explode.
+ */
+static uint32_t data_read_input(char *buf, uint32_t *size, void *param) {
+
+ /* some common variables. */
+ pkzip_data_s *info = (pkzip_data_s *)param;
+ uint32_t max_avail = (info->in_bytes - info->in_pos);
+ uint32_t to_read = *size;
+
+ /* check the case when not enough data available. */
+ if (to_read > max_avail) {
+ to_read = max_avail;
+ }
+
+ /* load data and increment offsets. */
+ memcpy(buf, info->in_buf + info->in_pos, to_read);
+ info->in_pos += to_read;
+
+ /* return bytes read. */
+ return to_read;
+}
+
+/*
+ * function for store output data used by mpq_pkzip "implode" and
+ * "explode" as userdefined callback.
+ *
+ * char *buf - pointer to data to be written.
+ * uint32_t *size - number of bytes to write.
+ * void *param - custom pointer, parameter of implode/explode.
+ */
+static void data_write_output(char *buf, uint32_t *size, void *param) {
+
+ /* some common variables. */
+ pkzip_data_s *info = (pkzip_data_s *)param;
+ uint32_t max_write = (info->max_out - info->out_pos);
+ uint32_t to_write = *size;
+
+ /* check the case when not enough space in the output buffer. */
+ if (to_write > max_write) {
+ to_write = max_write;
+ }
+
+ /* write output data and increments offsets. */
+ memcpy(info->out_buf + info->out_pos, buf, to_write);
+ info->out_pos += to_write;
+}
+
+/* this function extract the data from input stream. */
+static uint32_t expand(pkzip_cmp_s *mpq_pkzip) {
+
+ /* number of bytes to copy. */
+ uint32_t copy_bytes;
+
+ /* one byte from compressed file. */
+ uint32_t one_byte;
+
+ /* some common variables. */
+ uint32_t result;
+
+ /* initialize output buffer position. */
+ mpq_pkzip->out_pos = 0x1000;
+
+ /* check if end of data or error, so terminate decompress. */
+ while ((result = one_byte = decode_literal(mpq_pkzip)) < 0x305) {
+
+ /* check if one byte is greater than 0x100, which means 'repeat n - 0xFE bytes'. */
+ if (one_byte >= 0x100) {
+
+ /* ECX */
+ uint8_t *source;
+
+ /* EDX */
+ uint8_t *target;
+
+ /* some common variables. */
+ uint32_t copy_length = one_byte - 0xFE;
+ uint32_t move_back;
+
+ /* get length of data to copy. */
+ if ((move_back = decode_distance(mpq_pkzip, copy_length)) == 0) {
+ result = 0x306;
+ break;
+ }
+
+ /* target and source pointer. */
+ target = &mpq_pkzip->out_buf[mpq_pkzip->out_pos];
+ source = target - move_back;
+ mpq_pkzip->out_pos += copy_length;
+
+ /* copy until nothing left. */
+ while (copy_length-- > 0) {
+ *target++ = *source++;
+ }
+ } else {
+
+ /* byte is 0x100 great, so add one byte. */
+ mpq_pkzip->out_buf[mpq_pkzip->out_pos++] = (uint8_t)one_byte;
+ }
+
+ /* check if number of extracted bytes has reached 1/2 of output buffer, so flush output buffer. */
+ if (mpq_pkzip->out_pos >= 0x2000) {
+
+ /* copy decompressed data into user buffer. */
+ copy_bytes = 0x1000;
+ mpq_pkzip->write_buf((char *)&mpq_pkzip->out_buf[0x1000], &copy_bytes, mpq_pkzip->param);
+
+ /* check if there are some data left, keep them alive. */
+ memcpy(mpq_pkzip->out_buf, &mpq_pkzip->out_buf[0x1000], mpq_pkzip->out_pos - 0x1000);
+ mpq_pkzip->out_pos -= 0x1000;
+ }
+ }
+
+ /* copy the rest. */
+ copy_bytes = mpq_pkzip->out_pos - 0x1000;
+ mpq_pkzip->write_buf((char *)&mpq_pkzip->out_buf[0x1000], &copy_bytes, mpq_pkzip->param);
+
+ /* return copied bytes. */
+ return result;
+}
+
+/* this function explode the data stream. */
+uint32_t libmpq__do_decompress_pkzip(uint8_t *work_buf, void *param) {
+
+ /* some common variables. */
+ pkzip_cmp_s *mpq_pkzip = (pkzip_cmp_s *)work_buf;
+
+ /* set the whole work buffer to zeros. */
+ memset(mpq_pkzip, 0, sizeof(pkzip_cmp_s));
+
+ /* initialize work struct and load compressed data. */
+ mpq_pkzip->read_buf = data_read_input;
+ mpq_pkzip->write_buf = data_write_output;
+ mpq_pkzip->param = param;
+ mpq_pkzip->in_pos = sizeof(mpq_pkzip->in_buf);
+ mpq_pkzip->in_bytes = mpq_pkzip->read_buf((char *)mpq_pkzip->in_buf, &mpq_pkzip->in_pos, mpq_pkzip->param);
+
+ /* check if we have pkzip data. */
+ if (mpq_pkzip->in_bytes <= 4) {
+ return LIBMPQ_PKZIP_CMP_BAD_DATA;
+ }
+
+ /* get the compression type. */
+ mpq_pkzip->cmp_type = mpq_pkzip->in_buf[0];
+
+ /* get the dictionary size. */
+ mpq_pkzip->dsize_bits = mpq_pkzip->in_buf[1];
+
+ /* initialize 16-bit bit buffer. */
+ mpq_pkzip->bit_buf = mpq_pkzip->in_buf[2];
+
+ /* extra (over 8) bits. */
+ mpq_pkzip->extra_bits = 0;
+
+ /* position in input buffer. */
+ mpq_pkzip->in_pos = 3;
+
+ /* check if valid dictionary size. */
+ if (4 > mpq_pkzip->dsize_bits || mpq_pkzip->dsize_bits > 6) {
+ return LIBMPQ_PKZIP_CMP_INV_DICTSIZE;
+ }
+
+ /* shifted by 'sar' instruction. */
+ mpq_pkzip->dsize_mask = 0xFFFF >> (0x10 - mpq_pkzip->dsize_bits);
+
+ /* check if we are using binary compression. */
+ if (mpq_pkzip->cmp_type != LIBMPQ_PKZIP_CMP_BINARY) {
+
+ /* check if we are using ascii compression. */
+ if (mpq_pkzip->cmp_type != LIBMPQ_PKZIP_CMP_ASCII) {
+ return LIBMPQ_PKZIP_CMP_INV_MODE;
+ }
+
+ /* create ascii buffer. */
+ memcpy(mpq_pkzip->bits_asc, pkzip_bits_asc, sizeof(mpq_pkzip->bits_asc));
+ generate_tables_ascii(mpq_pkzip);
+ }
+
+ /* create the tables for decode. */
+ memcpy(mpq_pkzip->slen_bits, pkzip_slen_bits, sizeof(mpq_pkzip->slen_bits));
+ generate_tables_decode(0x10, mpq_pkzip->slen_bits, pkzip_len_code, mpq_pkzip->pos2);
+
+ /* create the tables for decode. */
+ memcpy(mpq_pkzip->clen_bits, pkzip_clen_bits, sizeof(mpq_pkzip->clen_bits));
+ memcpy(mpq_pkzip->len_base, pkzip_len_base, sizeof(mpq_pkzip->len_base));
+ memcpy(mpq_pkzip->dist_bits, pkzip_dist_bits, sizeof(mpq_pkzip->dist_bits));
+ generate_tables_decode(0x40, mpq_pkzip->dist_bits, pkzip_dist_code, mpq_pkzip->pos1);
+
+ /* check if data extraction works. */
+ if (expand(mpq_pkzip) != 0x306) {
+ return LIBMPQ_PKZIP_CMP_NO_ERROR;
+ }
+
+ /* something failed, so return error. */
+ return LIBMPQ_PKZIP_CMP_ABORT;
+}