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-rw-r--r--Modules/zlib/minigzip.c322
1 files changed, 322 insertions, 0 deletions
diff --git a/Modules/zlib/minigzip.c b/Modules/zlib/minigzip.c
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+++ b/Modules/zlib/minigzip.c
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+/* minigzip.c -- simulate gzip using the zlib compression library
+ * Copyright (C) 1995-2005 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 <stdio.h>
+#include "zlib.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>
+# 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
+
+#ifndef WIN32 /* unlink already in stdio.h for WIN32 */
+ extern int unlink OF((const char *));
+#endif
+
+#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
+
+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;
+
+ 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;
+ uInt len = (uInt)strlen(file);
+
+ 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 [-d] [-f] [-h] [-r] [-1 to -9] [files...]
+ * -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 uncompr = 0;
+ gzFile file;
+ char outmode[20];
+
+ strcpy(outmode, "wb6 ");
+
+ prog = argv[0];
+ argc--, argv++;
+
+ while (argc > 0) {
+ 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 {
+ do {
+ if (uncompr) {
+ file_uncompress(*argv);
+ } else {
+ file_compress(*argv, outmode);
+ }
+ } while (argv++, --argc);
+ }
+ return 0;
+}
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