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-rw-r--r--nse_zlib.cc989
1 files changed, 989 insertions, 0 deletions
diff --git a/nse_zlib.cc b/nse_zlib.cc
new file mode 100644
index 0000000..341aa51
--- /dev/null
+++ b/nse_zlib.cc
@@ -0,0 +1,989 @@
+/************************************************************************
+* Author : Tiago Dionizio <tiago.dionizio@gmail.com> *
+* Library : lzlib - Lua 5 interface to access zlib library functions *
+* *
+* Permission is hereby granted, free of charge, to any person obtaining *
+* a copy of this software and associated documentation files (the *
+* "Software"), to deal in the Software without restriction, including *
+* without limitation the rights to use, copy, modify, merge, publish, *
+* distribute, sublicense, and/or sell copies of the Software, and to *
+* permit persons to whom the Software is furnished to do so, subject to *
+* the following conditions: *
+* *
+* The above copyright notice and this permission notice shall be *
+* included in all copies or substantial portions of the Software. *
+* *
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, *
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY *
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, *
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE *
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
+************************************************************************/
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "nse_lua.h"
+
+#include <zlib.h>
+
+/*
+** =========================================================================
+** compile time options which determine available functionality
+** =========================================================================
+*/
+
+/* TODO
+
+- also call flush on table/userdata when flush function is detected
+- remove io_cb check inflate_block if condition
+- only set eos when ZSTREAM_END is reached
+- check for stream errors to close stream when really needed
+
+*/
+
+
+/*
+** =========================================================================
+** zlib stream metamethods
+** =========================================================================
+*/
+#define ZSTREAMMETA "zlib:zstream"
+
+#define LZ_ANY -1
+#define LZ_NONE 0
+#define LZ_DEFLATE 1
+#define LZ_INFLATE 2
+
+#if 0
+ #define LZ_BUFFER_SIZE LUAL_BUFFERSIZE
+#else
+ #define LZ_BUFFER_SIZE 8192
+#endif
+
+typedef struct {
+ /* zlib structures */
+ z_stream zstream;
+ /* stream state. LZ_DEFLATE | LZ_INFLATE */
+ int state;
+ int error;
+ int peek;
+ int eos;
+ /* user callback source for reading/writing */
+ int io_cb;
+ /* input buffer */
+ int i_buffer_ref;
+ size_t i_buffer_pos;
+ size_t i_buffer_len;
+ const char *i_buffer;
+ /* output buffer */
+ size_t o_buffer_len;
+ size_t o_buffer_max;
+ char o_buffer[LZ_BUFFER_SIZE];
+ /* dictionary */
+ const Bytef *dictionary;
+ size_t dictionary_len;
+} lz_stream;
+
+
+/* forward declarations */
+static int lzstream_docompress(lua_State *L, lz_stream *s, int from, int to, int flush);
+
+
+static lz_stream *lzstream_new(lua_State *L, int src) {
+ lz_stream *s = (lz_stream*)lua_newuserdata(L, sizeof(lz_stream));
+
+ luaL_getmetatable(L, ZSTREAMMETA);
+ lua_setmetatable(L, -2); /* set metatable */
+
+ s->state = LZ_NONE;
+ s->error = Z_OK;
+ s->eos = 0;
+ s->io_cb = LUA_REFNIL;
+
+ s->i_buffer = NULL;
+ s->i_buffer_ref = LUA_REFNIL;
+ s->i_buffer_pos = 0;
+ s->i_buffer_len = 0;
+
+ s->peek = 0;
+ s->o_buffer_len = 0;
+ s->o_buffer_max = sizeof(s->o_buffer) / sizeof(s->o_buffer[0]);
+
+ s->zstream.zalloc = Z_NULL;
+ s->zstream.zfree = Z_NULL;
+
+ /* prepare source */
+ if (lua_isstring(L, src)) {
+ lua_pushvalue(L, src);
+ s->i_buffer_ref = luaL_ref(L, LUA_REGISTRYINDEX);
+ s->i_buffer = lua_tolstring(L, src, &s->i_buffer_len);
+ } else {
+ /* table | function | userdata */
+ lua_pushvalue(L, src);
+ s->io_cb = luaL_ref(L, LUA_REGISTRYINDEX);
+ }
+ return s;
+}
+
+static void lzstream_cleanup(lua_State *L, lz_stream *s) {
+ if (s && s->state != LZ_NONE) {
+ if (s->state == LZ_INFLATE) {
+ inflateEnd(&s->zstream);
+ }
+ if (s->state == LZ_DEFLATE) {
+ deflateEnd(&s->zstream);
+ }
+
+ luaL_unref(L, LUA_REGISTRYINDEX, s->io_cb);
+ luaL_unref(L, LUA_REGISTRYINDEX, s->i_buffer_ref);
+ s->state = LZ_NONE;
+ }
+}
+
+/* ====================================================================== */
+
+static lz_stream *lzstream_get(lua_State *L, int index) {
+ lz_stream *s = (lz_stream*)luaL_checkudata(L, index, ZSTREAMMETA);
+ if (s == NULL) luaL_argerror(L, index, "bad zlib stream");
+ return s;
+}
+
+static lz_stream *lzstream_check(lua_State *L, int index, int state) {
+ lz_stream *s = lzstream_get(L, index);
+ if ((state != LZ_ANY && s->state != state) || s->state == LZ_NONE) {
+ luaL_argerror(L, index, "attempt to use invalid zlib stream");
+ }
+ return s;
+}
+
+/* ====================================================================== */
+
+static int lzstream_tostring(lua_State *L) {
+ lz_stream *s = (lz_stream*)luaL_checkudata(L, 1, ZSTREAMMETA);
+ if (s == NULL) return luaL_argerror(L, 1, "bad zlib stream");
+
+ if (s->state == LZ_NONE) {
+ lua_pushstring(L, "zlib stream (closed)");
+ } else if (s->state == LZ_DEFLATE) {
+ lua_pushfstring(L, "zlib deflate stream (%p)", (void*)s);
+ } else if (s->state == LZ_INFLATE) {
+ lua_pushfstring(L, "zlib inflate stream (%p)", (void*)s);
+ } else {
+ lua_pushfstring(L, "%p", (void*)s);
+ }
+
+ return 1;
+}
+
+/* ====================================================================== */
+
+static int lzstream_gc(lua_State *L) {
+ lz_stream *s = lzstream_get(L, 1);
+ lzstream_cleanup(L, s);
+ return 0;
+}
+
+/* ====================================================================== */
+
+static int lzstream_close(lua_State *L) {
+ lz_stream *s = lzstream_get(L, 1);
+
+ if (s->state == LZ_DEFLATE) {
+ lua_settop(L, 0);
+ lua_pushliteral(L, "");
+ return lzstream_docompress(L, s, 1, 1, Z_FINISH);
+ }
+
+ lzstream_cleanup(L, s);
+ lua_pushboolean(L, 1);
+ return 1;
+}
+
+/* ====================================================================== */
+
+static int lzstream_adler(lua_State *L) {
+ lz_stream *s = lzstream_check(L, 1, LZ_ANY);
+ lua_pushnumber(L, s->zstream.adler);
+ return 1;
+}
+
+/* ====================================================================== */
+
+/*
+ zlib.deflate(
+ sink: function | { write: function [, close: function, flush: function] },
+ compression level, [Z_DEFAILT_COMPRESSION]
+ method, [Z_DEFLATED]
+ windowBits, [15]
+ memLevel, [8]
+ strategy, [Z_DEFAULT_STRATEGY]
+ dictionary: [""]
+ )
+*/
+static int lzlib_deflate(lua_State *L) {
+ int level, method, windowBits, memLevel, strategy;
+ lz_stream *s;
+ const char *dictionary;
+ size_t dictionary_len;
+
+ if (lua_istable(L, 1) || lua_isuserdata(L, 1)) {
+ /* is there a :write function? */
+ lua_getfield(L, 1, "write");
+ if (!lua_isfunction(L, -1)) {
+ luaL_argerror(L, 1, "output parameter does not provide :write function");
+ }
+ lua_pop(L, 1);
+ }
+ else if (!lua_isfunction(L, 1)) {
+ luaL_argerror(L, 1, "output parameter must be a function, table or userdata value");
+ }
+
+ level = (int) luaL_optinteger(L, 2, Z_DEFAULT_COMPRESSION);
+ method = (int) luaL_optinteger(L, 3, Z_DEFLATED);
+ windowBits = (int) luaL_optinteger(L, 4, 15);
+ memLevel = (int) luaL_optinteger(L, 5, 8);
+ strategy = (int) luaL_optinteger(L, 6, Z_DEFAULT_STRATEGY);
+ dictionary = luaL_optlstring(L, 7, NULL, &dictionary_len);
+
+ s = lzstream_new(L, 1);
+
+ if (deflateInit2(&s->zstream, level, method, windowBits, memLevel, strategy) != Z_OK) {
+ lua_pushliteral(L, "call to deflateInit2 failed");
+ lua_error(L);
+ }
+
+ if (dictionary) {
+ if (deflateSetDictionary(&s->zstream, (const Bytef *) dictionary, dictionary_len) != Z_OK) {
+ lua_pushliteral(L, "call to deflateSetDictionnary failed");
+ lua_error(L);
+ }
+ }
+
+ s->state = LZ_DEFLATE;
+ return 1;
+}
+
+/*
+ zlib.inflate(
+ source: string | function | { read: function, close: function },
+ windowBits: number, [15]
+ dictionary: [""]
+ )
+*/
+static int lzlib_inflate(lua_State *L)
+{
+ int windowBits;
+ lz_stream *s;
+ int have_peek = 0;
+ const char *dictionary;
+ size_t dictionary_len;
+
+ if (lua_istable(L, 1) || lua_isuserdata(L, 1)) {
+ /* is there a :read function? */
+ lua_getfield(L, 1, "read");
+ if (!lua_isfunction(L, -1)) {
+ luaL_argerror(L, 1, "input parameter does not provide :read function");
+ }
+ lua_pop(L, 1);
+ /* check for peek function */
+ lua_getfield(L, 1, "peek");
+ have_peek = lua_isfunction(L, -1);
+ lua_pop(L, 1);
+ }
+ else if (!lua_isstring(L, 1) && !lua_isfunction(L, 1)) {
+ luaL_argerror(L, 1, "input parameter must be a string, function, table or userdata value");
+ }
+
+ windowBits = (int) luaL_optinteger(L, 2, 15);
+ dictionary = luaL_optlstring(L, 3, NULL, &dictionary_len);
+
+ s = lzstream_new(L, 1);
+
+ if (windowBits > 0 && windowBits < 16) {
+ windowBits |= 32;
+ }
+
+ if (inflateInit2(&s->zstream, windowBits) != Z_OK) {
+ lua_pushliteral(L, "call to inflateInit2 failed");
+ lua_error(L);
+ }
+
+ if (dictionary) {
+ s->dictionary = (const Bytef *) dictionary;
+ s->dictionary_len = dictionary_len;
+ }
+
+ s->peek = have_peek;
+ s->state = LZ_INFLATE;
+ return 1;
+}
+
+/* ====================================================================== */
+
+static int lz_pushresult (lua_State *L, lz_stream *s) {
+ if (s->error == Z_OK) {
+ lua_pushboolean(L, 1);
+ return 1;
+ } else {
+ lua_pushnil(L);
+ lua_pushstring(L, zError(s->error));
+ lua_pushinteger(L, s->error);
+ return 3;
+ }
+}
+
+/*
+ Get block to process:
+ - top of stack gets
+*/
+static const char* lzstream_fetch_block(lua_State *L, lz_stream *s, int hint) {
+ if (s->i_buffer_pos >= s->i_buffer_len) {
+ luaL_unref(L, LUA_REGISTRYINDEX, s->i_buffer_ref);
+ s->i_buffer_ref = LUA_NOREF;
+ s->i_buffer = NULL;
+
+ lua_rawgeti(L, LUA_REGISTRYINDEX, s->io_cb);
+ if (!lua_isnil(L, -1)) {
+ if (lua_isfunction(L, -1)) {
+ lua_pushinteger(L, hint);
+ lua_call(L, 1, 1);
+ } else {
+ lua_getfield(L, -1, (s->peek ? "peek" : "read"));
+ lua_insert(L, -2);
+ lua_pushinteger(L, hint);
+ lua_call(L, 2, 1);
+ }
+
+ if (lua_isstring(L, -1)) {
+ s->i_buffer_pos = 0;
+ s->i_buffer = lua_tolstring(L, -1, &s->i_buffer_len);
+ if (s->i_buffer_len > 0) {
+ s->i_buffer_ref = luaL_ref(L, LUA_REGISTRYINDEX);
+ } else {
+ lua_pop(L, 1);
+ }
+ } else if (lua_isnil(L, -1)) {
+ lua_pop(L, 1);
+ } else {
+ lua_pushliteral(L, "deflate callback must return string or nil");
+ lua_error(L);
+ }
+ } else {
+ lua_pop(L, 1);
+ }
+ }
+
+ return s->i_buffer;
+}
+
+static int lzstream_inflate_block(lua_State *L, lz_stream *s) {
+ if (lzstream_fetch_block(L, s, LZ_BUFFER_SIZE) || !s->eos) {
+ int r;
+
+ if (s->i_buffer_len == s->i_buffer_pos) {
+ s->zstream.next_in = NULL;
+ s->zstream.avail_in = 0;
+ } else {
+ s->zstream.next_in = (unsigned char*)(s->i_buffer + s->i_buffer_pos);
+ s->zstream.avail_in = s->i_buffer_len - s->i_buffer_pos;
+ }
+
+ s->zstream.next_out = (unsigned char*)s->o_buffer + s->o_buffer_len;
+ s->zstream.avail_out = s->o_buffer_max - s->o_buffer_len;
+
+ /* munch some more */
+ r = inflate(&s->zstream, Z_SYNC_FLUSH);
+
+ if (r == Z_NEED_DICT) {
+ if (s->dictionary == NULL) {
+ lua_pushliteral(L, "no inflate dictionary provided");
+ lua_error(L);
+ }
+
+ if (inflateSetDictionary(&s->zstream, s->dictionary, s->dictionary_len) != Z_OK) {
+ lua_pushliteral(L, "call to inflateSetDictionnary failed");
+ lua_error(L);
+ }
+
+ r = inflate(&s->zstream, Z_SYNC_FLUSH);
+ }
+
+ if (r != Z_OK && r != Z_STREAM_END && r != Z_BUF_ERROR) {
+ lzstream_cleanup(L, s);
+ s->error = r;
+ #if 1
+ lua_pushfstring(L, "failed to decompress [%d]", r);
+ lua_error(L);
+ #endif
+ }
+
+ if (r == Z_STREAM_END) {
+ luaL_unref(L, LUA_REGISTRYINDEX, s->i_buffer_ref);
+ s->i_buffer_ref = LUA_NOREF;
+ s->i_buffer = NULL;
+
+ s->eos = 1;
+ }
+
+ /* number of processed bytes */
+ if (s->peek) {
+ size_t processed = s->i_buffer_len - s->i_buffer_pos - s->zstream.avail_in;
+
+ lua_rawgeti(L, LUA_REGISTRYINDEX, s->io_cb);
+ lua_getfield(L, -1, "read");
+ lua_insert(L, -2);
+ lua_pushinteger(L, processed);
+ lua_call(L, 2, 0);
+ }
+
+ s->i_buffer_pos = s->i_buffer_len - s->zstream.avail_in;
+ s->o_buffer_len = s->o_buffer_max - s->zstream.avail_out;
+ }
+
+ return s->o_buffer_len;
+}
+
+/*
+** Remove n bytes from the output buffer.
+*/
+static void lzstream_remove(lz_stream *s, size_t n) {
+ memmove(s->o_buffer, s->o_buffer + n, s->o_buffer_len - n);
+ s->o_buffer_len -= n;
+}
+
+/*
+** Copy at most n bytes to buffer b and remove them from the
+** output stream buffer.
+*/
+static int lzstream_flush_buffer(lua_State *L, lz_stream *s, size_t n, luaL_Buffer *b) {
+ /* check output */
+ if (n > s->o_buffer_len) {
+ n = s->o_buffer_len;
+ }
+
+ if (n > 0) {
+ lua_pushlstring(L, s->o_buffer, n);
+ luaL_addvalue(b);
+
+ lzstream_remove(s, n);
+ }
+
+ return n;
+}
+
+/*
+ z:read(
+ {number | '*l' | '*a'}*
+ )
+*/
+static int lz_test_eof(lua_State *L, lz_stream *s) {
+ lua_pushlstring(L, NULL, 0);
+ if (s->o_buffer_len > 0) {
+ return 1;
+ } else if (s->eos) {
+ return 0;
+ } else {
+ return lzstream_inflate_block(L, s);
+ }
+}
+
+static int lz_read_line(lua_State *L, lz_stream *s) {
+ luaL_Buffer b;
+ size_t l = 0, n;
+
+ luaL_buffinit(L, &b);
+
+ if (s->o_buffer_len > 0 || !s->eos) do {
+ char *p = s->o_buffer;
+ size_t len = s->o_buffer_len;
+
+ /* find newline in output buffer */
+ for (n = 0; n < len; ++n, ++p) {
+ if (*p == '\n' || *p == '\r') {
+ int eat_nl = *p == '\r';
+ luaL_addlstring(&b, s->o_buffer, n);
+ lzstream_remove(s, n+1);
+ l += n;
+
+ if (eat_nl && lzstream_inflate_block(L, s)) {
+ if (s->o_buffer_len > 0 && *s->o_buffer == '\n') {
+ lzstream_remove(s, 1);
+ }
+ }
+
+ luaL_pushresult(&b);
+ return 1;
+ }
+ }
+
+ if (len > 0) {
+ luaL_addlstring(&b, s->o_buffer, len);
+ lzstream_remove(s, len);
+ l += len;
+ }
+ } while (lzstream_inflate_block(L, s));
+
+ luaL_pushresult(&b);
+ return l > 0 || !s->eos || s->o_buffer_len > 0;
+}
+
+
+static int lz_read_chars(lua_State *L, lz_stream *s, size_t n) {
+ size_t len;
+ luaL_Buffer b;
+ luaL_buffinit(L, &b);
+
+ if (s->o_buffer_len > 0 || !s->eos) do {
+ size_t rlen = lzstream_flush_buffer(L, s, n, &b);
+ n -= rlen;
+ } while (n > 0 && lzstream_inflate_block(L, s));
+
+ luaL_pushresult(&b);
+ lua_tolstring(L, -1, &len);
+ return n == 0 || len > 0;
+}
+
+static int lzstream_decompress(lua_State *L) {
+ lz_stream *s = lzstream_check(L, 1, LZ_INFLATE);
+ int nargs = lua_gettop(L) - 1;
+ int success;
+ int n;
+ if (nargs == 0) { /* no arguments? */
+ success = lz_read_line(L, s);
+ n = 3; /* to return 1 result */
+ }
+ else { /* ensure stack space for all results and for auxlib's buffer */
+ luaL_checkstack(L, nargs+LUA_MINSTACK, "too many arguments");
+ success = 1;
+ for (n = 2; nargs-- && success; n++) {
+ if (lua_type(L, n) == LUA_TNUMBER) {
+ size_t l = (size_t)lua_tointeger(L, n);
+ success = (l == 0) ? lz_test_eof(L, s) : lz_read_chars(L, s, l);
+ }
+ else {
+ const char *p = lua_tostring(L, n);
+ luaL_argcheck(L, p && p[0] == '*', n, "invalid option");
+ switch (p[1]) {
+ case 'l': /* line */
+ success = lz_read_line(L, s);
+ break;
+ case 'a': /* file */
+ lz_read_chars(L, s, ~((size_t)0)); /* read MAX_SIZE_T chars */
+ success = 1; /* always success */
+ break;
+ default:
+ return luaL_argerror(L, n, "invalid format");
+ }
+ }
+ }
+ }
+ if (s->error != Z_OK) {
+ return lz_pushresult(L, s);
+ }
+ if (!success) {
+ lua_pop(L, 1); /* remove last result */
+ lua_pushnil(L); /* push nil instead */
+ }
+ return n - 2;
+}
+
+
+static int lzstream_readline(lua_State *L) {
+ lz_stream *s;
+ int success;
+
+ s = lzstream_check(L, lua_upvalueindex(1), LZ_INFLATE);
+ success = lz_read_line(L, s);
+
+ if (s->error != Z_OK) {
+ return lz_pushresult(L, s);
+ }
+
+ if (success) {
+ return 1;
+ } else {
+ /* EOF */
+ return 0;
+ }
+}
+
+static int lzstream_lines(lua_State *L) {
+ lzstream_check(L, 1, LZ_INFLATE);
+ lua_settop(L, 1);
+ lua_pushcclosure(L, lzstream_readline, 1);
+ return 1;
+}
+
+/* ====================================================================== */
+
+static int lzstream_docompress(lua_State *L, lz_stream *s, int from, int to, int flush) {
+ int r, arg;
+ int self = 0;
+ size_t b_size = s->o_buffer_max;
+ unsigned char *b = (unsigned char *)s->o_buffer;
+
+ /* number of processed bytes */
+ lua_rawgeti(L, LUA_REGISTRYINDEX, s->io_cb);
+ if (!lua_isfunction(L, -1)) {
+ self = 1;
+ lua_getfield(L, -1, "write");
+ }
+
+ for (arg = from; arg <= to; arg++) {
+ s->zstream.next_in = (unsigned char*)luaL_checklstring(L, arg, (size_t*)&s->zstream.avail_in);
+
+ do {
+ s->zstream.next_out = b;
+ s->zstream.avail_out = b_size;
+
+ /* bake some more */
+ r = deflate(&s->zstream, flush);
+ if (r != Z_OK && r != Z_STREAM_END && r != Z_BUF_ERROR) {
+ lzstream_cleanup(L, s);
+ lua_pushboolean(L, 0);
+ lua_pushfstring(L, "failed to compress [%d]", r);
+ return 2;
+ }
+
+ if (s->zstream.avail_out != b_size) {
+ /* write output */
+ lua_pushvalue(L, -1); /* function */
+ if (self) lua_pushvalue(L, -3); /* self */
+ lua_pushlstring(L, (char*)b, b_size - s->zstream.avail_out); /* data */
+ lua_call(L, (self ? 2 : 1), 0);
+ }
+
+ if (r == Z_STREAM_END) {
+ lzstream_cleanup(L, s);
+ break;
+ }
+
+ /* process all input */
+ } while (s->zstream.avail_in > 0 || s->zstream.avail_out == 0);
+ }
+
+ lua_pushboolean(L, 1);
+ return 1;
+}
+
+static int lzstream_compress(lua_State *L) {
+ lz_stream *s = lzstream_check(L, 1, LZ_DEFLATE);
+ return lzstream_docompress(L, s, 2, lua_gettop(L), Z_NO_FLUSH);
+}
+
+
+/* ====================================================================== */
+
+static int lzstream_flush(lua_State *L) {
+ static int flush_values[] = { Z_SYNC_FLUSH, Z_FULL_FLUSH, Z_FINISH };
+ static const char *const flush_opts[] = { "sync", "full", "finish" };
+
+ lz_stream *s = lzstream_check(L, 1, LZ_DEFLATE);
+ int flush = luaL_checkoption(L, 2, flush_opts[0], flush_opts);
+
+ lua_settop(L, 0);
+ lua_pushliteral(L, "");
+ return lzstream_docompress(L, s, 1, 1, flush_values[flush]);
+}
+
+/*
+** =========================================================================
+** zlib functions
+** =========================================================================
+*/
+
+static int lzlib_version(lua_State *L)
+{
+ lua_pushstring(L, zlibVersion());
+ return 1;
+}
+
+/* ====================================================================== */
+static int lzlib_adler32(lua_State *L)
+{
+ if (lua_gettop(L) == 0)
+ {
+ /* adler32 initial value */
+ lua_pushnumber(L, adler32(0L, Z_NULL, 0));
+ }
+ else
+ {
+ /* update adler32 checksum */
+ size_t len;
+ int adler = (int) luaL_checkinteger(L, 1);
+ const unsigned char* buf = (unsigned char*)luaL_checklstring(L, 2, &len);
+
+ lua_pushnumber(L, adler32(adler, buf, len));
+ }
+ return 1;
+}
+
+/* ====================================================================== */
+static int lzlib_crc32(lua_State *L)
+{
+ if (lua_gettop(L) == 0)
+ {
+ /* crc32 initial value */
+ lua_pushnumber(L, crc32(0L, Z_NULL, 0));
+ }
+ else
+ {
+ /* update crc32 checksum */
+ size_t len;
+ int crc = (int) luaL_checkinteger(L, 1);
+ const unsigned char* buf = (unsigned char*)luaL_checklstring(L, 2, &len);
+
+ lua_pushnumber(L, crc32(crc, buf, len));
+ }
+ return 1;
+}
+
+/* ====================================================================== */
+
+
+static int lzlib_compress(lua_State *L) {
+ size_t avail_in;
+ const char *next_in = luaL_checklstring(L, 1, &avail_in);
+ int level = (int) luaL_optinteger(L, 2, Z_DEFAULT_COMPRESSION);
+ int method = (int) luaL_optinteger(L, 3, Z_DEFLATED);
+ int windowBits = (int) luaL_optinteger(L, 4, 15);
+ int memLevel = (int) luaL_optinteger(L, 5, 8);
+ int strategy = (int) luaL_optinteger(L, 6, Z_DEFAULT_STRATEGY);
+
+ int ret;
+ luaL_Buffer b;
+ z_stream zs;
+
+ luaL_buffinit(L, &b);
+
+ zs.zalloc = Z_NULL;
+ zs.zfree = Z_NULL;
+
+ zs.next_out = Z_NULL;
+ zs.avail_out = 0;
+ zs.next_in = Z_NULL;
+ zs.avail_in = 0;
+
+ ret = deflateInit2(&zs, level, method, windowBits, memLevel, strategy);
+
+ if (ret != Z_OK)
+ {
+ lua_pushnil(L);
+ lua_pushnumber(L, ret);
+ return 2;
+ }
+
+ zs.next_in = (unsigned char*)next_in;
+ zs.avail_in = avail_in;
+
+ for(;;)
+ {
+ zs.next_out = (unsigned char*)luaL_prepbuffer(&b);
+ zs.avail_out = LUAL_BUFFERSIZE;
+
+ /* munch some more */
+ ret = deflate(&zs, Z_FINISH);
+
+ /* push gathered data */
+ luaL_addsize(&b, LUAL_BUFFERSIZE - zs.avail_out);
+
+ /* done processing? */
+ if (ret == Z_STREAM_END)
+ break;
+
+ /* error condition? */
+ if (ret != Z_OK)
+ break;
+ }
+
+ /* cleanup */
+ deflateEnd(&zs);
+
+ luaL_pushresult(&b);
+ lua_pushnumber(L, ret);
+ return 2;
+}
+
+/* ====================================================================== */
+
+static int lzlib_decompress(lua_State *L)
+{
+ size_t avail_in;
+ const char *next_in = luaL_checklstring(L, 1, &avail_in);
+ int windowBits = (int) luaL_optinteger(L, 2, 15);
+
+ int ret;
+ luaL_Buffer b;
+ z_stream zs;
+
+ luaL_buffinit(L, &b);
+
+ zs.zalloc = Z_NULL;
+ zs.zfree = Z_NULL;
+
+ zs.next_out = Z_NULL;
+ zs.avail_out = 0;
+ zs.next_in = Z_NULL;
+ zs.avail_in = 0;
+
+ ret = inflateInit2(&zs, windowBits);
+
+ if (ret != Z_OK) {
+ lua_pushliteral(L, "failed to initialize zstream structures");
+ lua_error(L);
+ }
+
+ zs.next_in = (unsigned char*)next_in;
+ zs.avail_in = avail_in;
+
+ for (;;) {
+ zs.next_out = (unsigned char*)luaL_prepbuffer(&b);
+ zs.avail_out = LUAL_BUFFERSIZE;
+
+ /* bake some more */
+ ret = inflate(&zs, Z_FINISH);
+
+ /* push gathered data */
+ luaL_addsize(&b, LUAL_BUFFERSIZE - zs.avail_out);
+
+ /* done processing? */
+ if (ret == Z_STREAM_END)
+ break;
+
+ if (ret != Z_OK && ret != Z_BUF_ERROR) {
+ /* cleanup */
+ inflateEnd(&zs);
+
+ lua_pushliteral(L, "failed to process zlib stream");
+ lua_error(L);
+ }
+ }
+
+ /* cleanup */
+ inflateEnd(&zs);
+
+ luaL_pushresult(&b);
+ return 1;
+}
+
+
+/*
+** =========================================================================
+** Register functions
+** =========================================================================
+*/
+
+#if (LUA_VERSION_NUM >= 502)
+
+#define luaL_register(L,n,f) luaL_setfuncs(L,f,0)
+
+#endif
+
+LUALIB_API int luaopen_zlib(lua_State *L)
+{
+ const luaL_Reg lzstream_meta[] =
+ {
+ {"write", lzstream_compress },
+ {"read", lzstream_decompress },
+ {"lines", lzstream_lines },
+ {"flush", lzstream_flush },
+ {"close", lzstream_close },
+
+ {"adler", lzstream_adler },
+
+ {"__tostring", lzstream_tostring },
+ {"__gc", lzstream_gc },
+ {NULL, NULL}
+ };
+
+ const luaL_Reg zlib[] =
+ {
+ {"version", lzlib_version },
+ {"adler32", lzlib_adler32 },
+ {"crc32", lzlib_crc32 },
+
+ {"deflate", lzlib_deflate },
+ {"inflate", lzlib_inflate },
+
+ {"compress", lzlib_compress },
+ {"decompress", lzlib_decompress },
+
+ {NULL, NULL}
+ };
+
+ /* ====================================================================== */
+
+ /* create new metatable for zlib compression structures */
+ luaL_newmetatable(L, ZSTREAMMETA);
+ lua_pushliteral(L, "__index");
+ lua_pushvalue(L, -2); /* push metatable */
+ lua_rawset(L, -3); /* metatable.__index = metatable */
+
+ /*
+ ** Stack: metatable
+ */
+ luaL_register(L, NULL, lzstream_meta);
+
+ lua_pop(L, 1); /* remove metatable from stack */
+
+ /*
+ ** Stack:
+ */
+ lua_newtable(L);
+
+ lua_pushliteral (L, "_COPYRIGHT");
+ lua_pushliteral (L, "Copyright (C) 2003-2010 Tiago Dionizio");
+ lua_settable (L, -3);
+ lua_pushliteral (L, "_DESCRIPTION");
+ lua_pushliteral (L, "Lua 5 interface to access zlib library functions");
+ lua_settable (L, -3);
+ lua_pushliteral (L, "_VERSION");
+ lua_pushliteral (L, "lzlib 0.4-work3");
+ lua_settable (L, -3);
+
+#define PUSH_LITERAL(name) \
+ lua_pushliteral (L, #name); \
+ lua_pushinteger (L, Z_##name); \
+ lua_settable (L, -3);
+
+#define PUSH_NUMBER(name, value) \
+ lua_pushliteral (L, #name); \
+ lua_pushinteger (L, value); \
+ lua_settable (L, -3);
+
+ PUSH_LITERAL(NO_COMPRESSION)
+ PUSH_LITERAL(BEST_SPEED)
+ PUSH_LITERAL(BEST_COMPRESSION)
+ PUSH_LITERAL(DEFAULT_COMPRESSION)
+
+ PUSH_LITERAL(FILTERED)
+ PUSH_LITERAL(HUFFMAN_ONLY)
+#ifdef Z_RLE
+ PUSH_LITERAL(RLE)
+#endif
+#ifdef Z_FIXED
+ PUSH_LITERAL(FIXED)
+#endif
+ PUSH_LITERAL(DEFAULT_STRATEGY)
+
+ PUSH_NUMBER(MINIMUM_MEMLEVEL, 1)
+ PUSH_NUMBER(MAXIMUM_MEMLEVEL, 9)
+ PUSH_NUMBER(DEFAULT_MEMLEVEL, 8)
+
+ PUSH_NUMBER(DEFAULT_WINDOWBITS, 15)
+ PUSH_NUMBER(MINIMUM_WINDOWBITS, 8)
+ PUSH_NUMBER(MAXIMUM_WINDOWBITS, 15)
+
+ PUSH_NUMBER(GZIP_WINDOWBITS, 16)
+ PUSH_NUMBER(RAW_WINDOWBITS, -1)
+
+ luaL_register(L, NULL, zlib);
+
+ /*
+ ** Stack: zlib table
+ */
+ return 1;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-02 20:06:07 +0000