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| author | Jeffrey Armstrong <jeffrey.armstrong@approximatrix.com> | 2014-01-03 10:04:01 -0500 |
|---|---|---|
| committer | Jeffrey Armstrong <jeffrey.armstrong@approximatrix.com> | 2014-01-03 10:04:01 -0500 |
| commit | 50ff0e53d94c60860e768100f549e4dfe9110096 (patch) | |
| tree | 65175313745a4aad498d781092dd89f8fbd47276 /compress.c | |
| parent | 2719471cb97c721e929c98c6bad40a381269295e (diff) | |
| download | prism-50ff0e53d94c60860e768100f549e4dfe9110096.tar.gz prism-50ff0e53d94c60860e768100f549e4dfe9110096.zip | |
Files can now be committed to version control. Each version is stored in gzip'd form. Fix to MD5 calculation.
Diffstat (limited to 'compress.c')
| -rw-r--r-- | compress.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/compress.c b/compress.c new file mode 100644 index 0000000..1a19b65 --- /dev/null +++ b/compress.c @@ -0,0 +1,207 @@ +/* The following code is directly borrowed from:
+ *
+ *
+ * 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
+ Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler
+
+ 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.
+
+ Jean-loup Gailly Mark Adler
+ jloup@gzip.org madler@alumni.caltech.edu
+
+
+ The data format used by the zlib library is described by RFCs (Request for
+ Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950
+ (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
+*/
+
+
+/*
+ * 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 _MSC_VER
+# define snprintf _snprintf
+#endif
+
+#ifdef RISCOS
+# define fileno(file) file->__file
+#endif
+#if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
+# include <unix.h> /* for fileno */
+#endif
+
+#define BUFLEN 16384
+#define MAX_NAME_LEN 1024
+
+//#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(void *q, unsigned n, unsigned m)
+{
+ q = Z_NULL;
+ return calloc(n, m);
+}
+
+void myfree(void *q, void *p)
+{
+ q = Z_NULL;
+ free(p);
+}
+
+static void error(const char *msg)
+{
+ printf(" ERR: %s\n", msg);
+}
+
+/* ===========================================================================
+ * Compress input to output then close both files.
+ */
+
+void gz_compress(FILE *in, gzFile out)
+{
+ static char buf[BUFLEN];
+ int len;
+ int err;
+
+ for (;;) {
+ len = (int)fread(buf, 1, sizeof(buf), in);
+ if (ferror(in)) {
+ error("fread failed in gz_compress");
+ return;
+ }
+ 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");
+}
+
+
+/* ===========================================================================
+ * Uncompress input to output then close both files.
+ */
+void gz_uncompress(in, out)
+ gzFile in;
+ FILE *out;
+{
+ static 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 compressed file
+ */
+int file_compress(const char *file, const char *outfile)
+{
+ const char *mode = "wb6 ";
+ FILE *in;
+ gzFile out;
+
+ in = fopen(file, "rb");
+ if (in == NULL) {
+ printf(" ERR: can't open %s\n", file);
+ return -1;
+ }
+ out = gzopen(outfile, mode);
+ if (out == NULL) {
+ printf(" ERR: can't gzopen %s\n", outfile);
+ return -1;
+ }
+ gz_compress(in, out);
+
+ return 1;
+}
+
+
+/* ===========================================================================
+ * Uncompress the given file
+ */
+int file_uncompress(const char *infile, const char *outfile)
+{
+ FILE *out;
+ gzFile in;
+
+ in = gzopen(infile, "rb");
+ if (in == NULL) {
+ printf(" ERR: can't gzopen %s\n", infile);
+ return -1;
+ }
+ out = fopen(outfile, "wb");
+ if (out == NULL) {
+ printf(" ERR: can't open %s\n", outfile);
+ return -1;
+ }
+
+ gz_uncompress(in, out);
+ return 1;
+}
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