wip

src/compress_util.c

@@ -0,0 +1,126 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <errno.h>
+#include "compress_util.h"
+
+#define CHUNK 1024 
+
+void zlib_decompress_data(unsigned char *data_chunk, size_t file_length, unsigned char **buff, size_t *sz) {
+        int ret;
+        unsigned int have;
+        z_stream strm;
+        // Adding one to zero here
+        unsigned char out[CHUNK];
+        unsigned char in[CHUNK];
+
+        errno=0;
+        FILE *data_stream = fmemopen(data_chunk, file_length, "r");
+        FILE *of = open_memstream((char**)buff, sz);
+        if(data_stream == NULL) {
+                perror("F MEM OPEN");
+        }
+
+        strm.zalloc = Z_NULL;
+        strm.zfree = Z_NULL;
+        strm.opaque = Z_NULL;
+        strm.avail_in = 0;
+        strm.next_in = Z_NULL;
+        ret = inflateInit(&strm);
+        if(ret != Z_OK) {
+                return;
+        }
+
+        do {
+                strm.avail_in = fread(in, 1, CHUNK, data_stream);
+                if(ferror(data_stream)) {
+                        (void)inflateEnd(&strm);
+                        return;
+                }
+                if(strm.avail_in == 0) {
+                        break;
+                }
+                strm.next_in = in;
+        
+                do {
+                        strm.avail_out = CHUNK;
+                        strm.next_out = out;
+                        ret = inflate(&strm, Z_NO_FLUSH);
+                        assert(ret != Z_STREAM_ERROR);
+                        switch(ret) {
+                                case Z_NEED_DICT:
+                                        ret = Z_DATA_ERROR;
+                                case Z_DATA_ERROR:
+                                case Z_MEM_ERROR:
+                                        (void)inflateEnd(&strm);
+                                        printf("Error: %d\n", ret);
+                                        printf("MSG: %s\n", (char*)strm.msg);
+                                        return;
+                        }
+                        have = CHUNK - strm.avail_out;
+                        fwrite(out, 1, have, of);
+                } while(strm.avail_out == 0);
+        } while(ret != Z_STREAM_END);
+
+        (void)inflateEnd(&strm);
+
+        fclose(data_stream);
+        fclose(of);
+}
+
+void zlib_compress_data(unsigned char *data_chunk, size_t file_length, unsigned char **buff, size_t *sz) {
+        int ret, flush;
+        unsigned int have;
+        z_stream strm;
+        unsigned char in[CHUNK];
+        unsigned char out[CHUNK];
+        int level = 9;
+        int method = Z_DEFLATED;
+        int windowBits = 10;
+        int memLevel = 9;
+        //int strategy = Z_DEFAULT_STRATEGY;
+        int strategy = Z_FILTERED;
+
+        FILE *data_stream = fmemopen(data_chunk, file_length, "r");
+        FILE *out_data_stream = NULL;
+        out_data_stream = open_memstream((char**)buff, sz);
+
+        strm.zalloc = Z_NULL;
+        strm.zfree = Z_NULL;
+        strm.opaque = Z_NULL;
+        ret = deflateInit2(&strm, level, method, windowBits, memLevel, strategy);
+        if (ret != Z_OK) {
+                return;
+        }
+
+        do {
+                strm.avail_in = fread(in, 1, CHUNK, data_stream);
+                if (ferror(data_stream)) {
+                        (void)deflateEnd(&strm);
+                        return;
+                }
+                flush = feof(data_stream) ? Z_FINISH : Z_NO_FLUSH;
+                strm.next_in = in;
+
+                do {
+                        strm.avail_out = CHUNK;
+                        strm.next_out = out;
+
+                        ret = deflate(&strm, flush);
+                        assert(ret != Z_STREAM_ERROR);
+                        have = CHUNK - strm.avail_out;
+                        if(fwrite(out, 1, have, out_data_stream) != have || ferror(out_data_stream)) {
+                                (void)deflateEnd(&strm);
+                                return;
+                        }
+                } while(strm.avail_out == 0);
+                assert(strm.avail_in == 0);
+
+        } while(flush != Z_FINISH);
+        assert(ret == Z_STREAM_END);
+
+        fclose(data_stream);
+        fclose(out_data_stream);
+
+        (void)deflateEnd(&strm);
+}