From 417b4381dda4b88a1e382f821c8964cf8954307e Mon Sep 17 00:00:00 2001
From: David Monniaux <david.monniaux@univ-grenoble-alpes.fr>
Date: Tue, 29 Jan 2019 22:31:50 +0100
Subject: https://github.com/pfalcon/uzlib

---
 test/monniaux/uzlib/examples/tgunzip/tgunzip.c | 167 +++++++++++++++++++++++++
 1 file changed, 167 insertions(+)
 create mode 100644 test/monniaux/uzlib/examples/tgunzip/tgunzip.c

(limited to 'test/monniaux/uzlib/examples/tgunzip/tgunzip.c')

diff --git a/test/monniaux/uzlib/examples/tgunzip/tgunzip.c b/test/monniaux/uzlib/examples/tgunzip/tgunzip.c
new file mode 100644
index 00000000..dcf15eca
--- /dev/null
+++ b/test/monniaux/uzlib/examples/tgunzip/tgunzip.c
@@ -0,0 +1,167 @@
+/*
+ * tgunzip  -  gzip decompressor example
+ *
+ * Copyright (c) 2003 by Joergen Ibsen / Jibz
+ * All Rights Reserved
+ *
+ * http://www.ibsensoftware.com/
+ *
+ * Copyright (c) 2014-2016 by Paul Sokolovsky
+ *
+ * This software is provided 'as-is', without any express
+ * or implied warranty.  In no event will the authors be
+ * held liable for any damages arising from the use of
+ * this software.
+ *
+ * Permission is granted to anyone to use this software
+ * for any purpose, including commercial applications,
+ * and to alter it and redistribute it freely, subject to
+ * the following restrictions:
+ *
+ * 1. The origin of this software must not be
+ *    misrepresented; you must not claim that you
+ *    wrote the original software. If you use this
+ *    software in a product, an acknowledgment in
+ *    the product documentation would be appreciated
+ *    but is not required.
+ *
+ * 2. Altered source versions must be plainly marked
+ *    as such, and must not be misrepresented as
+ *    being the original software.
+ *
+ * 3. This notice may not be removed or altered from
+ *    any source distribution.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "uzlib.h"
+
+/* produce decompressed output in chunks of this size */
+/* defauly is to decompress byte by byte; can be any other length */
+#define OUT_CHUNK_SIZE 1
+
+void exit_error(const char *what)
+{
+   printf("ERROR: %s\n", what);
+   exit(1);
+}
+
+int main(int argc, char *argv[])
+{
+    FILE *fin, *fout;
+    unsigned int len, dlen, outlen;
+    const unsigned char *source;
+    unsigned char *dest;
+    int res;
+
+    printf("tgunzip - example from the tiny inflate library (www.ibsensoftware.com)\n\n");
+
+    if (argc < 3)
+    {
+       printf(
+          "Syntax: tgunzip <source> <destination>\n\n"
+          "Both input and output are kept in memory, so do not use this on huge files.\n");
+
+       return 1;
+    }
+
+    uzlib_init();
+
+    /* -- open files -- */
+
+    if ((fin = fopen(argv[1], "rb")) == NULL) exit_error("source file");
+
+    if ((fout = fopen(argv[2], "wb")) == NULL) exit_error("destination file");
+
+    /* -- read source -- */
+
+    fseek(fin, 0, SEEK_END);
+
+    len = ftell(fin);
+
+    fseek(fin, 0, SEEK_SET);
+
+    source = (unsigned char *)malloc(len);
+
+    if (source == NULL) exit_error("memory");
+
+    if (fread((unsigned char*)source, 1, len, fin) != len) exit_error("read");
+
+    fclose(fin);
+
+    if (len < 4) exit_error("file too small");
+
+    /* -- get decompressed length -- */
+
+    dlen =            source[len - 1];
+    dlen = 256*dlen + source[len - 2];
+    dlen = 256*dlen + source[len - 3];
+    dlen = 256*dlen + source[len - 4];
+
+    outlen = dlen;
+
+    /* there can be mismatch between length in the trailer and actual
+       data stream; to avoid buffer overruns on overlong streams, reserve
+       one extra byte */
+    dlen++;
+
+    dest = (unsigned char *)malloc(dlen);
+
+    if (dest == NULL) exit_error("memory");
+
+    /* -- decompress data -- */
+
+    struct uzlib_uncomp d;
+//    uzlib_uncompress_init(&d, malloc(32768), 32768);
+    uzlib_uncompress_init(&d, NULL, 0);
+
+    /* all 3 fields below must be initialized by user */
+    d.source = source;
+    d.source_limit = source + len - 4;
+    d.source_read_cb = NULL;
+
+    res = uzlib_gzip_parse_header(&d);
+    if (res != TINF_OK) {
+        printf("Error parsing header: %d\n", res);
+        exit(1);
+    }
+
+    d.dest_start = d.dest = dest;
+
+    while (dlen) {
+        unsigned int chunk_len = dlen < OUT_CHUNK_SIZE ? dlen : OUT_CHUNK_SIZE;
+        d.dest_limit = d.dest + chunk_len;
+        res = uzlib_uncompress_chksum(&d);
+        dlen -= chunk_len;
+        if (res != TINF_OK) {
+            break;
+        }
+    }
+
+    if (res != TINF_DONE) {
+        printf("Error during decompression: %d\n", res);
+        exit(-res);
+    }
+
+    printf("decompressed %lu bytes\n", d.dest - dest);
+
+#if 0
+    if (d.dest - dest != gz.dlen) {
+        printf("Invalid decompressed length: %lu vs %u\n", d.dest - dest, gz.dlen);
+    }
+
+    if (tinf_crc32(dest, gz.dlen) != gz.crc32) {
+        printf("Invalid decompressed crc32\n");
+    }
+#endif
+
+    /* -- write output -- */
+
+    fwrite(dest, 1, outlen, fout);
+
+    fclose(fout);
+
+    return 0;
+}
-- 
cgit