Move example.c and minigzip.c to examples/ directory.

3 files changed, 1241 insertions, 0 deletions

diff --git a/examples/README.examples b/examples/README.examples
index 56a3171..fddb8df 100644
--- a/examples/README.examples
+++ b/examples/README.examples
@@ -6,6 +6,10 @@ enough.c
     - calculates the maximum table space used in inflate tree
       construction over all possible Huffman codes
 
+example.c
+    usage examples of zlib
+    - used in zlib build Makefile for testing
+
 fitblk.c
     compress just enough input to nearly fill a requested output size
     - zlib isn't designed to do this, but fitblk does it anyway
@@ -34,6 +38,11 @@ gzlog.h
       and deflateSetDictionary()
     - illustrates use of a gzip header extra field
 
+minigzip.c
+    minimal implementation of gzip-like functionality using zlib
+    - used in zlib build Makefile for testing
+    - is not meant for and should not be used as a gzip replacement
+
 zlib_how.html
     painfully comprehensive description of zpipe.c (see below)
     - describes in excruciating detail the use of deflate() and inflate()
diff --git a/examples/example.c b/examples/example.c
new file mode 100644
index 0000000..f515a48
--- /dev/null
+++ b/examples/example.c
@@ -0,0 +1,601 @@
+/* example.c -- usage example of the zlib compression library
+ * Copyright (C) 1995-2006, 2011 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/* @(#) $Id$ */
+
+#include "zlib.h"
+#include <stdio.h>
+
+#ifdef STDC
+#  include <string.h>
+#  include <stdlib.h>
+#endif
+
+#if defined(VMS) || defined(RISCOS)
+#  define TESTFILE "foo-gz"
+#else
+#  define TESTFILE "foo.gz"
+#endif
+
+#define CHECK_ERR(err, msg) { \
+    if (err != Z_OK) { \
+        fprintf(stderr, "%s error: %d\n", msg, err); \
+        exit(1); \
+    } \
+}
+
+const char hello[] = "hello, hello!";
+/* "hello world" would be more standard, but the repeated "hello"
+ * stresses the compression code better, sorry...
+ */
+
+const char dictionary[] = "hello";
+uLong dictId; /* Adler32 value of the dictionary */
+
+void test_deflate       OF((Byte *compr, uLong comprLen));
+void test_inflate       OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_large_deflate OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_large_inflate OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_flush         OF((Byte *compr, uLong *comprLen));
+void test_sync          OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_dict_deflate  OF((Byte *compr, uLong comprLen));
+void test_dict_inflate  OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+int  main               OF((int argc, char *argv[]));
+
+
+#ifdef Z_SOLO
+
+void *myalloc OF((void *, unsigned, unsigned));
+void myfree OF((void *, void *));
+
+void *myalloc(q, n, m)
+    void *q;
+    unsigned n, m;
+{
+    q = Z_NULL;
+    return calloc(n, m);
+}
+
+void myfree(void *q, void *p)
+{
+    q = Z_NULL;
+    free(p);
+}
+
+static alloc_func zalloc = myalloc;
+static free_func zfree = myfree;
+
+#else /* !Z_SOLO */
+
+static alloc_func zalloc = (alloc_func)0;
+static free_func zfree = (free_func)0;
+
+void test_compress      OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_gzio          OF((const char *fname,
+                            Byte *uncompr, uLong uncomprLen));
+
+/* ===========================================================================
+ * Test compress() and uncompress()
+ */
+void test_compress(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    uLong len = (uLong)strlen(hello)+1;
+
+    err = compress(compr, &comprLen, (const Bytef*)hello, len);
+    CHECK_ERR(err, "compress");
+
+    strcpy((char*)uncompr, "garbage");
+
+    err = uncompress(uncompr, &uncomprLen, compr, comprLen);
+    CHECK_ERR(err, "uncompress");
+
+    if (strcmp((char*)uncompr, hello)) {
+        fprintf(stderr, "bad uncompress\n");
+        exit(1);
+    } else {
+        printf("uncompress(): %s\n", (char *)uncompr);
+    }
+}
+
+/* ===========================================================================
+ * Test read/write of .gz files
+ */
+void test_gzio(fname, uncompr, uncomprLen)
+    const char *fname; /* compressed file name */
+    Byte *uncompr;
+    uLong uncomprLen;
+{
+#ifdef NO_GZCOMPRESS
+    fprintf(stderr, "NO_GZCOMPRESS -- gz* functions cannot compress\n");
+#else
+    int err;
+    int len = (int)strlen(hello)+1;
+    gzFile file;
+    z_off_t pos;
+
+    file = gzopen(fname, "wb");
+    if (file == NULL) {
+        fprintf(stderr, "gzopen error\n");
+        exit(1);
+    }
+    gzputc(file, 'h');
+    if (gzputs(file, "ello") != 4) {
+        fprintf(stderr, "gzputs err: %s\n", gzerror(file, &err));
+        exit(1);
+    }
+    if (gzprintf(file, ", %s!", "hello") != 8) {
+        fprintf(stderr, "gzprintf err: %s\n", gzerror(file, &err));
+        exit(1);
+    }
+    gzseek(file, 1L, SEEK_CUR); /* add one zero byte */
+    gzclose(file);
+
+    file = gzopen(fname, "rb");
+    if (file == NULL) {
+        fprintf(stderr, "gzopen error\n");
+        exit(1);
+    }
+    strcpy((char*)uncompr, "garbage");
+
+    if (gzread(file, uncompr, (unsigned)uncomprLen) != len) {
+        fprintf(stderr, "gzread err: %s\n", gzerror(file, &err));
+        exit(1);
+    }
+    if (strcmp((char*)uncompr, hello)) {
+        fprintf(stderr, "bad gzread: %s\n", (char*)uncompr);
+        exit(1);
+    } else {
+        printf("gzread(): %s\n", (char*)uncompr);
+    }
+
+    pos = gzseek(file, -8L, SEEK_CUR);
+    if (pos != 6 || gztell(file) != pos) {
+        fprintf(stderr, "gzseek error, pos=%ld, gztell=%ld\n",
+                (long)pos, (long)gztell(file));
+        exit(1);
+    }
+
+    if (gzgetc(file) != ' ') {
+        fprintf(stderr, "gzgetc error\n");
+        exit(1);
+    }
+
+    if (gzungetc(' ', file) != ' ') {
+        fprintf(stderr, "gzungetc error\n");
+        exit(1);
+    }
+
+    gzgets(file, (char*)uncompr, (int)uncomprLen);
+    if (strlen((char*)uncompr) != 7) { /* " hello!" */
+        fprintf(stderr, "gzgets err after gzseek: %s\n", gzerror(file, &err));
+        exit(1);
+    }
+    if (strcmp((char*)uncompr, hello + 6)) {
+        fprintf(stderr, "bad gzgets after gzseek\n");
+        exit(1);
+    } else {
+        printf("gzgets() after gzseek: %s\n", (char*)uncompr);
+    }
+
+    gzclose(file);
+#endif
+}
+
+#endif /* Z_SOLO */
+
+/* ===========================================================================
+ * Test deflate() with small buffers
+ */
+void test_deflate(compr, comprLen)
+    Byte *compr;
+    uLong comprLen;
+{
+    z_stream c_stream; /* compression stream */
+    int err;
+    uLong len = (uLong)strlen(hello)+1;
+
+    c_stream.zalloc = zalloc;
+    c_stream.zfree = zfree;
+    c_stream.opaque = (voidpf)0;
+
+    err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
+    CHECK_ERR(err, "deflateInit");
+
+    c_stream.next_in  = (Bytef*)hello;
+    c_stream.next_out = compr;
+
+    while (c_stream.total_in != len && c_stream.total_out < comprLen) {
+        c_stream.avail_in = c_stream.avail_out = 1; /* force small buffers */
+        err = deflate(&c_stream, Z_NO_FLUSH);
+        CHECK_ERR(err, "deflate");
+    }
+    /* Finish the stream, still forcing small buffers: */
+    for (;;) {
+        c_stream.avail_out = 1;
+        err = deflate(&c_stream, Z_FINISH);
+        if (err == Z_STREAM_END) break;
+        CHECK_ERR(err, "deflate");
+    }
+
+    err = deflateEnd(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+}
+
+/* ===========================================================================
+ * Test inflate() with small buffers
+ */
+void test_inflate(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    z_stream d_stream; /* decompression stream */
+
+    strcpy((char*)uncompr, "garbage");
+
+    d_stream.zalloc = zalloc;
+    d_stream.zfree = zfree;
+    d_stream.opaque = (voidpf)0;
+
+    d_stream.next_in  = compr;
+    d_stream.avail_in = 0;
+    d_stream.next_out = uncompr;
+
+    err = inflateInit(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    while (d_stream.total_out < uncomprLen && d_stream.total_in < comprLen) {
+        d_stream.avail_in = d_stream.avail_out = 1; /* force small buffers */
+        err = inflate(&d_stream, Z_NO_FLUSH);
+        if (err == Z_STREAM_END) break;
+        CHECK_ERR(err, "inflate");
+    }
+
+    err = inflateEnd(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    if (strcmp((char*)uncompr, hello)) {
+        fprintf(stderr, "bad inflate\n");
+        exit(1);
+    } else {
+        printf("inflate(): %s\n", (char *)uncompr);
+    }
+}
+
+/* ===========================================================================
+ * Test deflate() with large buffers and dynamic change of compression level
+ */
+void test_large_deflate(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    z_stream c_stream; /* compression stream */
+    int err;
+
+    c_stream.zalloc = zalloc;
+    c_stream.zfree = zfree;
+    c_stream.opaque = (voidpf)0;
+
+    err = deflateInit(&c_stream, Z_BEST_SPEED);
+    CHECK_ERR(err, "deflateInit");
+
+    c_stream.next_out = compr;
+    c_stream.avail_out = (uInt)comprLen;
+
+    /* At this point, uncompr is still mostly zeroes, so it should compress
+     * very well:
+     */
+    c_stream.next_in = uncompr;
+    c_stream.avail_in = (uInt)uncomprLen;
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate");
+    if (c_stream.avail_in != 0) {
+        fprintf(stderr, "deflate not greedy\n");
+        exit(1);
+    }
+
+    /* Feed in already compressed data and switch to no compression: */
+    deflateParams(&c_stream, Z_NO_COMPRESSION, Z_DEFAULT_STRATEGY);
+    c_stream.next_in = compr;
+    c_stream.avail_in = (uInt)comprLen/2;
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate");
+
+    /* Switch back to compressing mode: */
+    deflateParams(&c_stream, Z_BEST_COMPRESSION, Z_FILTERED);
+    c_stream.next_in = uncompr;
+    c_stream.avail_in = (uInt)uncomprLen;
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "deflate");
+
+    err = deflate(&c_stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        fprintf(stderr, "deflate should report Z_STREAM_END\n");
+        exit(1);
+    }
+    err = deflateEnd(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+}
+
+/* ===========================================================================
+ * Test inflate() with large buffers
+ */
+void test_large_inflate(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    z_stream d_stream; /* decompression stream */
+
+    strcpy((char*)uncompr, "garbage");
+
+    d_stream.zalloc = zalloc;
+    d_stream.zfree = zfree;
+    d_stream.opaque = (voidpf)0;
+
+    d_stream.next_in  = compr;
+    d_stream.avail_in = (uInt)comprLen;
+
+    err = inflateInit(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    for (;;) {
+        d_stream.next_out = uncompr;            /* discard the output */
+        d_stream.avail_out = (uInt)uncomprLen;
+        err = inflate(&d_stream, Z_NO_FLUSH);
+        if (err == Z_STREAM_END) break;
+        CHECK_ERR(err, "large inflate");
+    }
+
+    err = inflateEnd(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    if (d_stream.total_out != 2*uncomprLen + comprLen/2) {
+        fprintf(stderr, "bad large inflate: %ld\n", d_stream.total_out);
+        exit(1);
+    } else {
+        printf("large_inflate(): OK\n");
+    }
+}
+
+/* ===========================================================================
+ * Test deflate() with full flush
+ */
+void test_flush(compr, comprLen)
+    Byte *compr;
+    uLong *comprLen;
+{
+    z_stream c_stream; /* compression stream */
+    int err;
+    uInt len = (uInt)strlen(hello)+1;
+
+    c_stream.zalloc = zalloc;
+    c_stream.zfree = zfree;
+    c_stream.opaque = (voidpf)0;
+
+    err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
+    CHECK_ERR(err, "deflateInit");
+
+    c_stream.next_in  = (Bytef*)hello;
+    c_stream.next_out = compr;
+    c_stream.avail_in = 3;
+    c_stream.avail_out = (uInt)*comprLen;
+    err = deflate(&c_stream, Z_FULL_FLUSH);
+    CHECK_ERR(err, "deflate");
+
+    compr[3]++; /* force an error in first compressed block */
+    c_stream.avail_in = len - 3;
+
+    err = deflate(&c_stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        CHECK_ERR(err, "deflate");
+    }
+    err = deflateEnd(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+
+    *comprLen = c_stream.total_out;
+}
+
+/* ===========================================================================
+ * Test inflateSync()
+ */
+void test_sync(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    z_stream d_stream; /* decompression stream */
+
+    strcpy((char*)uncompr, "garbage");
+
+    d_stream.zalloc = zalloc;
+    d_stream.zfree = zfree;
+    d_stream.opaque = (voidpf)0;
+
+    d_stream.next_in  = compr;
+    d_stream.avail_in = 2; /* just read the zlib header */
+
+    err = inflateInit(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    d_stream.next_out = uncompr;
+    d_stream.avail_out = (uInt)uncomprLen;
+
+    inflate(&d_stream, Z_NO_FLUSH);
+    CHECK_ERR(err, "inflate");
+
+    d_stream.avail_in = (uInt)comprLen-2;   /* read all compressed data */
+    err = inflateSync(&d_stream);           /* but skip the damaged part */
+    CHECK_ERR(err, "inflateSync");
+
+    err = inflate(&d_stream, Z_FINISH);
+    if (err != Z_DATA_ERROR) {
+        fprintf(stderr, "inflate should report DATA_ERROR\n");
+        /* Because of incorrect adler32 */
+        exit(1);
+    }
+    err = inflateEnd(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    printf("after inflateSync(): hel%s\n", (char *)uncompr);
+}
+
+/* ===========================================================================
+ * Test deflate() with preset dictionary
+ */
+void test_dict_deflate(compr, comprLen)
+    Byte *compr;
+    uLong comprLen;
+{
+    z_stream c_stream; /* compression stream */
+    int err;
+
+    c_stream.zalloc = zalloc;
+    c_stream.zfree = zfree;
+    c_stream.opaque = (voidpf)0;
+
+    err = deflateInit(&c_stream, Z_BEST_COMPRESSION);
+    CHECK_ERR(err, "deflateInit");
+
+    err = deflateSetDictionary(&c_stream,
+                (const Bytef*)dictionary, (int)sizeof(dictionary));
+    CHECK_ERR(err, "deflateSetDictionary");
+
+    dictId = c_stream.adler;
+    c_stream.next_out = compr;
+    c_stream.avail_out = (uInt)comprLen;
+
+    c_stream.next_in = (Bytef*)hello;
+    c_stream.avail_in = (uInt)strlen(hello)+1;
+
+    err = deflate(&c_stream, Z_FINISH);
+    if (err != Z_STREAM_END) {
+        fprintf(stderr, "deflate should report Z_STREAM_END\n");
+        exit(1);
+    }
+    err = deflateEnd(&c_stream);
+    CHECK_ERR(err, "deflateEnd");
+}
+
+/* ===========================================================================
+ * Test inflate() with a preset dictionary
+ */
+void test_dict_inflate(compr, comprLen, uncompr, uncomprLen)
+    Byte *compr, *uncompr;
+    uLong comprLen, uncomprLen;
+{
+    int err;
+    z_stream d_stream; /* decompression stream */
+
+    strcpy((char*)uncompr, "garbage");
+
+    d_stream.zalloc = zalloc;
+    d_stream.zfree = zfree;
+    d_stream.opaque = (voidpf)0;
+
+    d_stream.next_in  = compr;
+    d_stream.avail_in = (uInt)comprLen;
+
+    err = inflateInit(&d_stream);
+    CHECK_ERR(err, "inflateInit");
+
+    d_stream.next_out = uncompr;
+    d_stream.avail_out = (uInt)uncomprLen;
+
+    for (;;) {
+        err = inflate(&d_stream, Z_NO_FLUSH);
+        if (err == Z_STREAM_END) break;
+        if (err == Z_NEED_DICT) {
+            if (d_stream.adler != dictId) {
+                fprintf(stderr, "unexpected dictionary");
+                exit(1);
+            }
+            err = inflateSetDictionary(&d_stream, (const Bytef*)dictionary,
+                                       (int)sizeof(dictionary));
+        }
+        CHECK_ERR(err, "inflate with dict");
+    }
+
+    err = inflateEnd(&d_stream);
+    CHECK_ERR(err, "inflateEnd");
+
+    if (strcmp((char*)uncompr, hello)) {
+        fprintf(stderr, "bad inflate with dict\n");
+        exit(1);
+    } else {
+        printf("inflate with dictionary: %s\n", (char *)uncompr);
+    }
+}
+
+/* ===========================================================================
+ * Usage:  example [output.gz  [input.gz]]
+ */
+
+int main(argc, argv)
+    int argc;
+    char *argv[];
+{
+    Byte *compr, *uncompr;
+    uLong comprLen = 10000*sizeof(int); /* don't overflow on MSDOS */
+    uLong uncomprLen = comprLen;
+    static const char* myVersion = ZLIB_VERSION;
+
+    if (zlibVersion()[0] != myVersion[0]) {
+        fprintf(stderr, "incompatible zlib version\n");
+        exit(1);
+
+    } else if (strcmp(zlibVersion(), ZLIB_VERSION) != 0) {
+        fprintf(stderr, "warning: different zlib version\n");
+    }
+
+    printf("zlib version %s = 0x%04x, compile flags = 0x%lx\n",
+            ZLIB_VERSION, ZLIB_VERNUM, zlibCompileFlags());
+
+    compr    = (Byte*)calloc((uInt)comprLen, 1);
+    uncompr  = (Byte*)calloc((uInt)uncomprLen, 1);
+    /* compr and uncompr are cleared to avoid reading uninitialized
+     * data and to ensure that uncompr compresses well.
+     */
+    if (compr == Z_NULL || uncompr == Z_NULL) {
+        printf("out of memory\n");
+        exit(1);
+    }
+
+#ifdef Z_SOLO
+    argc = strlen(argv[0]);
+#else
+    test_compress(compr, comprLen, uncompr, uncomprLen);
+
+    test_gzio((argc > 1 ? argv[1] : TESTFILE),
+              uncompr, uncomprLen);
+#endif
+
+    test_deflate(compr, comprLen);
+    test_inflate(compr, comprLen, uncompr, uncomprLen);
+
+    test_large_deflate(compr, comprLen, uncompr, uncomprLen);
+    test_large_inflate(compr, comprLen, uncompr, uncomprLen);
+
+    test_flush(compr, &comprLen);
+    test_sync(compr, comprLen, uncompr, uncomprLen);
+    comprLen = uncomprLen;
+
+    test_dict_deflate(compr, comprLen);
+    test_dict_inflate(compr, comprLen, uncompr, uncomprLen);
+
+    free(compr);
+    free(uncompr);
+
+    return 0;
+}
diff --git a/examples/minigzip.c b/examples/minigzip.c
new file mode 100644
index 0000000..8317344
--- /dev/null
+++ b/examples/minigzip.c
@@ -0,0 +1,631 @@
+/* minigzip.c -- simulate gzip using the zlib compression library
+ * Copyright (C) 1995-2006, 2010, 2011 Jean-loup Gailly.
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+/*
+ * minigzip is a minimal implementation of the gzip utility. This is
+ * only an example of using zlib and isn't meant to replace the
+ * full-featured gzip. No attempt is made to deal with file systems
+ * limiting names to 14 or 8+3 characters, etc... Error checking is
+ * very limited. So use minigzip only for testing; use gzip for the
+ * real thing. On MSDOS, use only on file names without extension
+ * or in pipe mode.
+ */
+
+/* @(#) $Id$ */
+
+#include "zlib.h"
+#include <stdio.h>
+
+#ifdef STDC
+#  include <string.h>
+#  include <stdlib.h>
+#endif
+
+#ifdef USE_MMAP
+#  include <sys/types.h>
+#  include <sys/mman.h>
+#  include <sys/stat.h>
+#endif
+
+#if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__CYGWIN__)
+#  include <fcntl.h>
+#  include <io.h>
+#  ifdef UNDER_CE
+#    include <stdlib.h>
+#  endif
+#  define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
+#else
+#  define SET_BINARY_MODE(file)
+#endif
+
+#ifdef VMS
+#  define unlink delete
+#  define GZ_SUFFIX "-gz"
+#endif
+#ifdef RISCOS
+#  define unlink remove
+#  define GZ_SUFFIX "-gz"
+#  define fileno(file) file->__file
+#endif
+#if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
+#  include <unix.h> /* for fileno */
+#endif
+
+#if !defined(Z_HAVE_UNISTD_H) && !defined(_LARGEFILE64_SOURCE)
+#ifndef WIN32 /* unlink already in stdio.h for WIN32 */
+  extern int unlink OF((const char *));
+#endif
+#endif
+
+#if defined(UNDER_CE)
+#  include <windows.h>
+#  define perror(s) pwinerror(s)
+
+/* Map the Windows error number in ERROR to a locale-dependent error
+   message string and return a pointer to it.  Typically, the values
+   for ERROR come from GetLastError.
+
+   The string pointed to shall not be modified by the application,
+   but may be overwritten by a subsequent call to strwinerror
+
+   The strwinerror function does not change the current setting
+   of GetLastError.  */
+
+static char *strwinerror (error)
+     DWORD error;
+{
+    static char buf[1024];
+
+    wchar_t *msgbuf;
+    DWORD lasterr = GetLastError();
+    DWORD chars = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM
+        | FORMAT_MESSAGE_ALLOCATE_BUFFER,
+        NULL,
+        error,
+        0, /* Default language */
+        (LPVOID)&msgbuf,
+        0,
+        NULL);
+    if (chars != 0) {
+        /* If there is an \r\n appended, zap it.  */
+        if (chars >= 2
+            && msgbuf[chars - 2] == '\r' && msgbuf[chars - 1] == '\n') {
+            chars -= 2;
+            msgbuf[chars] = 0;
+        }
+
+        if (chars > sizeof (buf) - 1) {
+            chars = sizeof (buf) - 1;
+            msgbuf[chars] = 0;
+        }
+
+        wcstombs(buf, msgbuf, chars + 1);
+        LocalFree(msgbuf);
+    }
+    else {
+        sprintf(buf, "unknown win32 error (%ld)", error);
+    }
+
+    SetLastError(lasterr);
+    return buf;
+}
+
+static void pwinerror (s)
+    const char *s;
+{
+    if (s && *s)
+        fprintf(stderr, "%s: %s\n", s, strwinerror(GetLastError ()));
+    else
+        fprintf(stderr, "%s\n", strwinerror(GetLastError ()));
+}
+
+#endif /* UNDER_CE */
+
+#ifndef GZ_SUFFIX
+#  define GZ_SUFFIX ".gz"
+#endif
+#define SUFFIX_LEN (sizeof(GZ_SUFFIX)-1)
+
+#define BUFLEN      16384
+#define MAX_NAME_LEN 1024
+
+#ifdef MAXSEG_64K
+#  define local static
+   /* Needed for systems with limitation on stack size. */
+#else
+#  define local
+#endif
+
+#ifdef Z_SOLO
+/* for Z_SOLO, create simplified gz* functions using deflate and inflate */
+
+#if defined(Z_HAVE_UNISTD_H) || defined(Z_LARGE)
+#  include <unistd.h>       /* for unlink() */
+#endif
+
+void *myalloc OF((void *, unsigned, unsigned));
+void myfree OF((void *, void *));
+
+void *myalloc(q, n, m)
+    void *q;
+    unsigned n, m;
+{
+    q = Z_NULL;
+    return calloc(n, m);
+}
+
+void myfree(q, p)
+    void *q, *p;
+{
+    q = Z_NULL;
+    free(p);
+}
+
+typedef struct gzFile_s {
+    FILE *file;
+    int write;
+    int err;
+    char *msg;
+    z_stream strm;
+} *gzFile;
+
+gzFile gzopen OF((const char *, const char *));
+gzFile gzdopen OF((int, const char *));
+gzFile gz_open OF((const char *, int, const char *));
+
+gzFile gzopen(path, mode)
+const char *path;
+const char *mode;
+{
+    return gz_open(path, -1, mode);
+}
+
+gzFile gzdopen(fd, mode)
+int fd;
+const char *mode;
+{
+    return gz_open(NULL, fd, mode);
+}
+
+gzFile gz_open(path, fd, mode)
+    const char *path;
+    int fd;
+    const char *mode;
+{
+    gzFile gz;
+    int ret;
+
+    gz = malloc(sizeof(gzFile));
+    if (gz == NULL)
+        return NULL;
+    gz->write = strchr(mode, 'w') != NULL;
+    gz->strm.zalloc = myalloc;
+    gz->strm.zfree = myfree;
+    gz->strm.opaque = Z_NULL;
+    if (gz->write)
+        ret = deflateInit2(&(gz->strm), -1, 8, 15 + 16, 8, 0);
+    else {
+        gz->strm.next_in = 0;
+        gz->strm.avail_in = Z_NULL;
+        ret = inflateInit2(&(gz->strm), 15 + 16);
+    }
+    if (ret != Z_OK) {
+        free(gz);
+        return NULL;
+    }
+    gz->file = path == NULL ? fdopen(fd, gz->write ? "wb" : "rb") :
+                              fopen(path, gz->write ? "wb" : "rb");
+    if (gz->file == NULL) {
+        gz->write ? deflateEnd(&(gz->strm)) : inflateEnd(&(gz->strm));
+        free(gz);
+        return NULL;
+    }
+    gz->err = 0;
+    gz->msg = "";
+    return gz;
+}
+
+int gzwrite OF((gzFile, const void *, unsigned));
+
+int gzwrite(gz, buf, len)
+    gzFile gz;
+    const void *buf;
+    unsigned len;
+{
+    z_stream *strm;
+    unsigned char out[BUFLEN];
+
+    if (gz == NULL || !gz->write)
+        return 0;
+    strm = &(gz->strm);
+    strm->next_in = (void *)buf;
+    strm->avail_in = len;
+    do {
+        strm->next_out = out;
+        strm->avail_out = BUFLEN;
+        (void)deflate(strm, Z_NO_FLUSH);
+        fwrite(out, 1, BUFLEN - strm->avail_out, gz->file);
+    } while (strm->avail_out == 0);
+    return len;
+}
+
+int gzread OF((gzFile, void *, unsigned));
+
+int gzread(gz, buf, len)
+    gzFile gz;
+    void *buf;
+    unsigned len;
+{
+    int ret;
+    unsigned got;
+    unsigned char in[1];
+    z_stream *strm;
+
+    if (gz == NULL || gz->write)
+        return 0;
+    if (gz->err)
+        return 0;
+    strm = &(gz->strm);
+    strm->next_out = (void *)buf;
+    strm->avail_out = len;
+    do {
+        got = fread(in, 1, 1, gz->file);
+        if (got == 0)
+            break;
+        strm->next_in = in;
+        strm->avail_in = 1;
+        ret = inflate(strm, Z_NO_FLUSH);
+        if (ret == Z_DATA_ERROR) {
+            gz->err = Z_DATA_ERROR;
+            gz->msg = strm->msg;
+            return 0;
+        }
+        if (ret == Z_STREAM_END)
+            inflateReset(strm);
+    } while (strm->avail_out);
+    return len - strm->avail_out;
+}
+
+int gzclose OF((gzFile));
+
+int gzclose(gz)
+    gzFile gz;
+{
+    z_stream *strm;
+    unsigned char out[BUFLEN];
+
+    if (gz == NULL)
+        return Z_STREAM_ERROR;
+    strm = &(gz->strm);
+    if (gz->write) {
+        strm->next_in = Z_NULL;
+        strm->avail_in = 0;
+        do {
+            strm->next_out = out;
+            strm->avail_out = BUFLEN;
+            (void)deflate(strm, Z_FINISH);
+            fwrite(out, 1, BUFLEN - strm->avail_out, gz->file);
+        } while (strm->avail_out == 0);
+        deflateEnd(strm);
+    }
+    else
+        inflateEnd(strm);
+    fclose(gz->file);
+    free(gz);
+    return Z_OK;
+}
+
+const char *gzerror OF((gzFile, int *));
+
+const char *gzerror(gz, err)
+    gzFile gz;
+    int *err;
+{
+    *err = gz->err;
+    return gz->msg;
+}
+
+#endif
+
+char *prog;
+
+void error            OF((const char *msg));
+void gz_compress      OF((FILE   *in, gzFile out));
+#ifdef USE_MMAP
+int  gz_compress_mmap OF((FILE   *in, gzFile out));
+#endif
+void gz_uncompress    OF((gzFile in, FILE   *out));
+void file_compress    OF((char  *file, char *mode));
+void file_uncompress  OF((char  *file));
+int  main             OF((int argc, char *argv[]));
+
+/* ===========================================================================
+ * Display error message and exit
+ */
+void error(msg)
+    const char *msg;
+{
+    fprintf(stderr, "%s: %s\n", prog, msg);
+    exit(1);
+}
+
+/* ===========================================================================
+ * Compress input to output then close both files.
+ */
+
+void gz_compress(in, out)
+    FILE   *in;
+    gzFile out;
+{
+    local char buf[BUFLEN];
+    int len;
+    int err;
+
+#ifdef USE_MMAP
+    /* Try first compressing with mmap. If mmap fails (minigzip used in a
+     * pipe), use the normal fread loop.
+     */
+    if (gz_compress_mmap(in, out) == Z_OK) return;
+#endif
+    for (;;) {
+        len = (int)fread(buf, 1, sizeof(buf), in);
+        if (ferror(in)) {
+            perror("fread");
+            exit(1);
+        }
+        if (len == 0) break;
+
+        if (gzwrite(out, buf, (unsigned)len) != len) error(gzerror(out, &err));
+    }
+    fclose(in);
+    if (gzclose(out) != Z_OK) error("failed gzclose");
+}
+
+#ifdef USE_MMAP /* MMAP version, Miguel Albrecht <malbrech@eso.org> */
+
+/* Try compressing the input file at once using mmap. Return Z_OK if
+ * if success, Z_ERRNO otherwise.
+ */
+int gz_compress_mmap(in, out)
+    FILE   *in;
+    gzFile out;
+{
+    int len;
+    int err;
+    int ifd = fileno(in);
+    caddr_t buf;    /* mmap'ed buffer for the entire input file */
+    off_t buf_len;  /* length of the input file */
+    struct stat sb;
+
+    /* Determine the size of the file, needed for mmap: */
+    if (fstat(ifd, &sb) < 0) return Z_ERRNO;
+    buf_len = sb.st_size;
+    if (buf_len <= 0) return Z_ERRNO;
+
+    /* Now do the actual mmap: */
+    buf = mmap((caddr_t) 0, buf_len, PROT_READ, MAP_SHARED, ifd, (off_t)0);
+    if (buf == (caddr_t)(-1)) return Z_ERRNO;
+
+    /* Compress the whole file at once: */
+    len = gzwrite(out, (char *)buf, (unsigned)buf_len);
+
+    if (len != (int)buf_len) error(gzerror(out, &err));
+
+    munmap(buf, buf_len);
+    fclose(in);
+    if (gzclose(out) != Z_OK) error("failed gzclose");
+    return Z_OK;
+}
+#endif /* USE_MMAP */
+
+/* ===========================================================================
+ * Uncompress input to output then close both files.
+ */
+void gz_uncompress(in, out)
+    gzFile in;
+    FILE   *out;
+{
+    local char buf[BUFLEN];
+    int len;
+    int err;
+
+    for (;;) {
+        len = gzread(in, buf, sizeof(buf));
+        if (len < 0) error (gzerror(in, &err));
+        if (len == 0) break;
+
+        if ((int)fwrite(buf, 1, (unsigned)len, out) != len) {
+            error("failed fwrite");
+        }
+    }
+    if (fclose(out)) error("failed fclose");
+
+    if (gzclose(in) != Z_OK) error("failed gzclose");
+}
+
+
+/* ===========================================================================
+ * Compress the given file: create a corresponding .gz file and remove the
+ * original.
+ */
+void file_compress(file, mode)
+    char  *file;
+    char  *mode;
+{
+    local char outfile[MAX_NAME_LEN];
+    FILE  *in;
+    gzFile out;
+
+    if (strlen(file) + strlen(GZ_SUFFIX) >= sizeof(outfile)) {
+        fprintf(stderr, "%s: filename too long\n", prog);
+        exit(1);
+    }
+
+    strcpy(outfile, file);
+    strcat(outfile, GZ_SUFFIX);
+
+    in = fopen(file, "rb");
+    if (in == NULL) {
+        perror(file);
+        exit(1);
+    }
+    out = gzopen(outfile, mode);
+    if (out == NULL) {
+        fprintf(stderr, "%s: can't gzopen %s\n", prog, outfile);
+        exit(1);
+    }
+    gz_compress(in, out);
+
+    unlink(file);
+}
+
+
+/* ===========================================================================
+ * Uncompress the given file and remove the original.
+ */
+void file_uncompress(file)
+    char  *file;
+{
+    local char buf[MAX_NAME_LEN];
+    char *infile, *outfile;
+    FILE  *out;
+    gzFile in;
+    size_t len = strlen(file);
+
+    if (len + strlen(GZ_SUFFIX) >= sizeof(buf)) {
+        fprintf(stderr, "%s: filename too long\n", prog);
+        exit(1);
+    }
+
+    strcpy(buf, file);
+
+    if (len > SUFFIX_LEN && strcmp(file+len-SUFFIX_LEN, GZ_SUFFIX) == 0) {
+        infile = file;
+        outfile = buf;
+        outfile[len-3] = '\0';
+    } else {
+        outfile = file;
+        infile = buf;
+        strcat(infile, GZ_SUFFIX);
+    }
+    in = gzopen(infile, "rb");
+    if (in == NULL) {
+        fprintf(stderr, "%s: can't gzopen %s\n", prog, infile);
+        exit(1);
+    }
+    out = fopen(outfile, "wb");
+    if (out == NULL) {
+        perror(file);
+        exit(1);
+    }
+
+    gz_uncompress(in, out);
+
+    unlink(infile);
+}
+
+
+/* ===========================================================================
+ * Usage:  minigzip [-c] [-d] [-f] [-h] [-r] [-1 to -9] [files...]
+ *   -c : write to standard output
+ *   -d : decompress
+ *   -f : compress with Z_FILTERED
+ *   -h : compress with Z_HUFFMAN_ONLY
+ *   -r : compress with Z_RLE
+ *   -1 to -9 : compression level
+ */
+
+int main(argc, argv)
+    int argc;
+    char *argv[];
+{
+    int copyout = 0;
+    int uncompr = 0;
+    gzFile file;
+    char *bname, outmode[20];
+
+    strcpy(outmode, "wb6 ");
+
+    prog = argv[0];
+    bname = strrchr(argv[0], '/');
+    if (bname)
+      bname++;
+    else
+      bname = argv[0];
+    argc--, argv++;
+
+    if (!strcmp(bname, "gunzip"))
+      uncompr = 1;
+    else if (!strcmp(bname, "zcat"))
+      copyout = uncompr = 1;
+
+    while (argc > 0) {
+      if (strcmp(*argv, "-c") == 0)
+        copyout = 1;
+      else if (strcmp(*argv, "-d") == 0)
+        uncompr = 1;
+      else if (strcmp(*argv, "-f") == 0)
+        outmode[3] = 'f';
+      else if (strcmp(*argv, "-h") == 0)
+        outmode[3] = 'h';
+      else if (strcmp(*argv, "-r") == 0)
+        outmode[3] = 'R';
+      else if ((*argv)[0] == '-' && (*argv)[1] >= '1' && (*argv)[1] <= '9' &&
+               (*argv)[2] == 0)
+        outmode[2] = (*argv)[1];
+      else
+        break;
+      argc--, argv++;
+    }
+    if (outmode[3] == ' ')
+        outmode[3] = 0;
+    if (argc == 0) {
+        SET_BINARY_MODE(stdin);
+        SET_BINARY_MODE(stdout);
+        if (uncompr) {
+            file = gzdopen(fileno(stdin), "rb");
+            if (file == NULL) error("can't gzdopen stdin");
+            gz_uncompress(file, stdout);
+        } else {
+            file = gzdopen(fileno(stdout), outmode);
+            if (file == NULL) error("can't gzdopen stdout");
+            gz_compress(stdin, file);
+        }
+    } else {
+        if (copyout) {
+            SET_BINARY_MODE(stdout);
+        }
+        do {
+            if (uncompr) {
+                if (copyout) {
+                    file = gzopen(*argv, "rb");
+                    if (file == NULL)
+                        fprintf(stderr, "%s: can't gzopen %s\n", prog, *argv);
+                    else
+                        gz_uncompress(file, stdout);
+                } else {
+                    file_uncompress(*argv);
+                }
+            } else {
+                if (copyout) {
+                    FILE * in = fopen(*argv, "rb");
+
+                    if (in == NULL) {
+                        perror(*argv);
+                    } else {
+                        file = gzdopen(fileno(stdout), outmode);
+                        if (file == NULL) error("can't gzdopen stdout");
+
+                        gz_compress(in, file);
+                    }
+
+                } else {
+                    file_compress(*argv, outmode);
+                }
+            }
+        } while (argv++, --argc);
+    }
+    return 0;
+}