michael@0: /* minigzip.c -- simulate gzip using the zlib compression library
michael@0:  * Copyright (C) 1995-2006, 2010 Jean-loup Gailly.
michael@0:  * For conditions of distribution and use, see copyright notice in zlib.h
michael@0:  */
michael@0: 
michael@0: /*
michael@0:  * minigzip is a minimal implementation of the gzip utility. This is
michael@0:  * only an example of using zlib and isn't meant to replace the
michael@0:  * full-featured gzip. No attempt is made to deal with file systems
michael@0:  * limiting names to 14 or 8+3 characters, etc... Error checking is
michael@0:  * very limited. So use minigzip only for testing; use gzip for the
michael@0:  * real thing. On MSDOS, use only on file names without extension
michael@0:  * or in pipe mode.
michael@0:  */
michael@0: 
michael@0: /* @(#) $Id$ */
michael@0: 
michael@0: #include "zlib.h"
michael@0: #include <stdio.h>
michael@0: 
michael@0: #ifdef STDC
michael@0: #  include <string.h>
michael@0: #  include <stdlib.h>
michael@0: #endif
michael@0: 
michael@0: #ifdef USE_MMAP
michael@0: #  include <sys/types.h>
michael@0: #  include <sys/mman.h>
michael@0: #  include <sys/stat.h>
michael@0: #endif
michael@0: 
michael@0: #if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__CYGWIN__)
michael@0: #  include <fcntl.h>
michael@0: #  include <io.h>
michael@0: #  ifdef UNDER_CE
michael@0: #    include <stdlib.h>
michael@0: #  endif
michael@0: #  define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
michael@0: #else
michael@0: #  define SET_BINARY_MODE(file)
michael@0: #endif
michael@0: 
michael@0: #ifdef VMS
michael@0: #  define unlink delete
michael@0: #  define GZ_SUFFIX "-gz"
michael@0: #endif
michael@0: #ifdef RISCOS
michael@0: #  define unlink remove
michael@0: #  define GZ_SUFFIX "-gz"
michael@0: #  define fileno(file) file->__file
michael@0: #endif
michael@0: #if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
michael@0: #  include <unix.h> /* for fileno */
michael@0: #endif
michael@0: 
michael@0: #if !defined(Z_HAVE_UNISTD_H) && !defined(_LARGEFILE64_SOURCE)
michael@0: #ifndef WIN32 /* unlink already in stdio.h for WIN32 */
michael@0:   extern int unlink OF((const char *));
michael@0: #endif
michael@0: #endif
michael@0: 
michael@0: #if defined(UNDER_CE)
michael@0: #  include <windows.h>
michael@0: #  define perror(s) pwinerror(s)
michael@0: 
michael@0: /* Map the Windows error number in ERROR to a locale-dependent error
michael@0:    message string and return a pointer to it.  Typically, the values
michael@0:    for ERROR come from GetLastError.
michael@0: 
michael@0:    The string pointed to shall not be modified by the application,
michael@0:    but may be overwritten by a subsequent call to strwinerror
michael@0: 
michael@0:    The strwinerror function does not change the current setting
michael@0:    of GetLastError.  */
michael@0: 
michael@0: static char *strwinerror (error)
michael@0:      DWORD error;
michael@0: {
michael@0:     static char buf[1024];
michael@0: 
michael@0:     wchar_t *msgbuf;
michael@0:     DWORD lasterr = GetLastError();
michael@0:     DWORD chars = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM
michael@0:         | FORMAT_MESSAGE_ALLOCATE_BUFFER,
michael@0:         NULL,
michael@0:         error,
michael@0:         0, /* Default language */
michael@0:         (LPVOID)&msgbuf,
michael@0:         0,
michael@0:         NULL);
michael@0:     if (chars != 0) {
michael@0:         /* If there is an \r\n appended, zap it.  */
michael@0:         if (chars >= 2
michael@0:             && msgbuf[chars - 2] == '\r' && msgbuf[chars - 1] == '\n') {
michael@0:             chars -= 2;
michael@0:             msgbuf[chars] = 0;
michael@0:         }
michael@0: 
michael@0:         if (chars > sizeof (buf) - 1) {
michael@0:             chars = sizeof (buf) - 1;
michael@0:             msgbuf[chars] = 0;
michael@0:         }
michael@0: 
michael@0:         wcstombs(buf, msgbuf, chars + 1);
michael@0:         LocalFree(msgbuf);
michael@0:     }
michael@0:     else {
michael@0:         sprintf(buf, "unknown win32 error (%ld)", error);
michael@0:     }
michael@0: 
michael@0:     SetLastError(lasterr);
michael@0:     return buf;
michael@0: }
michael@0: 
michael@0: static void pwinerror (s)
michael@0:     const char *s;
michael@0: {
michael@0:     if (s && *s)
michael@0:         fprintf(stderr, "%s: %s\n", s, strwinerror(GetLastError ()));
michael@0:     else
michael@0:         fprintf(stderr, "%s\n", strwinerror(GetLastError ()));
michael@0: }
michael@0: 
michael@0: #endif /* UNDER_CE */
michael@0: 
michael@0: #ifndef GZ_SUFFIX
michael@0: #  define GZ_SUFFIX ".gz"
michael@0: #endif
michael@0: #define SUFFIX_LEN (sizeof(GZ_SUFFIX)-1)
michael@0: 
michael@0: #define BUFLEN      16384
michael@0: #define MAX_NAME_LEN 1024
michael@0: 
michael@0: #ifdef MAXSEG_64K
michael@0: #  define local static
michael@0:    /* Needed for systems with limitation on stack size. */
michael@0: #else
michael@0: #  define local
michael@0: #endif
michael@0: 
michael@0: char *prog;
michael@0: 
michael@0: void error            OF((const char *msg));
michael@0: void gz_compress      OF((FILE   *in, gzFile out));
michael@0: #ifdef USE_MMAP
michael@0: int  gz_compress_mmap OF((FILE   *in, gzFile out));
michael@0: #endif
michael@0: void gz_uncompress    OF((gzFile in, FILE   *out));
michael@0: void file_compress    OF((char  *file, char *mode));
michael@0: void file_uncompress  OF((char  *file));
michael@0: int  main             OF((int argc, char *argv[]));
michael@0: 
michael@0: /* ===========================================================================
michael@0:  * Display error message and exit
michael@0:  */
michael@0: void error(msg)
michael@0:     const char *msg;
michael@0: {
michael@0:     fprintf(stderr, "%s: %s\n", prog, msg);
michael@0:     exit(1);
michael@0: }
michael@0: 
michael@0: /* ===========================================================================
michael@0:  * Compress input to output then close both files.
michael@0:  */
michael@0: 
michael@0: void gz_compress(in, out)
michael@0:     FILE   *in;
michael@0:     gzFile out;
michael@0: {
michael@0:     local char buf[BUFLEN];
michael@0:     int len;
michael@0:     int err;
michael@0: 
michael@0: #ifdef USE_MMAP
michael@0:     /* Try first compressing with mmap. If mmap fails (minigzip used in a
michael@0:      * pipe), use the normal fread loop.
michael@0:      */
michael@0:     if (gz_compress_mmap(in, out) == Z_OK) return;
michael@0: #endif
michael@0:     for (;;) {
michael@0:         len = (int)fread(buf, 1, sizeof(buf), in);
michael@0:         if (ferror(in)) {
michael@0:             perror("fread");
michael@0:             exit(1);
michael@0:         }
michael@0:         if (len == 0) break;
michael@0: 
michael@0:         if (gzwrite(out, buf, (unsigned)len) != len) error(gzerror(out, &err));
michael@0:     }
michael@0:     fclose(in);
michael@0:     if (gzclose(out) != Z_OK) error("failed gzclose");
michael@0: }
michael@0: 
michael@0: #ifdef USE_MMAP /* MMAP version, Miguel Albrecht <malbrech@eso.org> */
michael@0: 
michael@0: /* Try compressing the input file at once using mmap. Return Z_OK if
michael@0:  * if success, Z_ERRNO otherwise.
michael@0:  */
michael@0: int gz_compress_mmap(in, out)
michael@0:     FILE   *in;
michael@0:     gzFile out;
michael@0: {
michael@0:     int len;
michael@0:     int err;
michael@0:     int ifd = fileno(in);
michael@0:     caddr_t buf;    /* mmap'ed buffer for the entire input file */
michael@0:     off_t buf_len;  /* length of the input file */
michael@0:     struct stat sb;
michael@0: 
michael@0:     /* Determine the size of the file, needed for mmap: */
michael@0:     if (fstat(ifd, &sb) < 0) return Z_ERRNO;
michael@0:     buf_len = sb.st_size;
michael@0:     if (buf_len <= 0) return Z_ERRNO;
michael@0: 
michael@0:     /* Now do the actual mmap: */
michael@0:     buf = mmap((caddr_t) 0, buf_len, PROT_READ, MAP_SHARED, ifd, (off_t)0);
michael@0:     if (buf == (caddr_t)(-1)) return Z_ERRNO;
michael@0: 
michael@0:     /* Compress the whole file at once: */
michael@0:     len = gzwrite(out, (char *)buf, (unsigned)buf_len);
michael@0: 
michael@0:     if (len != (int)buf_len) error(gzerror(out, &err));
michael@0: 
michael@0:     munmap(buf, buf_len);
michael@0:     fclose(in);
michael@0:     if (gzclose(out) != Z_OK) error("failed gzclose");
michael@0:     return Z_OK;
michael@0: }
michael@0: #endif /* USE_MMAP */
michael@0: 
michael@0: /* ===========================================================================
michael@0:  * Uncompress input to output then close both files.
michael@0:  */
michael@0: void gz_uncompress(in, out)
michael@0:     gzFile in;
michael@0:     FILE   *out;
michael@0: {
michael@0:     local char buf[BUFLEN];
michael@0:     int len;
michael@0:     int err;
michael@0: 
michael@0:     for (;;) {
michael@0:         len = gzread(in, buf, sizeof(buf));
michael@0:         if (len < 0) error (gzerror(in, &err));
michael@0:         if (len == 0) break;
michael@0: 
michael@0:         if ((int)fwrite(buf, 1, (unsigned)len, out) != len) {
michael@0:             error("failed fwrite");
michael@0:         }
michael@0:     }
michael@0:     if (fclose(out)) error("failed fclose");
michael@0: 
michael@0:     if (gzclose(in) != Z_OK) error("failed gzclose");
michael@0: }
michael@0: 
michael@0: 
michael@0: /* ===========================================================================
michael@0:  * Compress the given file: create a corresponding .gz file and remove the
michael@0:  * original.
michael@0:  */
michael@0: void file_compress(file, mode)
michael@0:     char  *file;
michael@0:     char  *mode;
michael@0: {
michael@0:     local char outfile[MAX_NAME_LEN];
michael@0:     FILE  *in;
michael@0:     gzFile out;
michael@0: 
michael@0:     if (strlen(file) + strlen(GZ_SUFFIX) >= sizeof(outfile)) {
michael@0:         fprintf(stderr, "%s: filename too long\n", prog);
michael@0:         exit(1);
michael@0:     }
michael@0: 
michael@0:     strcpy(outfile, file);
michael@0:     strcat(outfile, GZ_SUFFIX);
michael@0: 
michael@0:     in = fopen(file, "rb");
michael@0:     if (in == NULL) {
michael@0:         perror(file);
michael@0:         exit(1);
michael@0:     }
michael@0:     out = gzopen(outfile, mode);
michael@0:     if (out == NULL) {
michael@0:         fprintf(stderr, "%s: can't gzopen %s\n", prog, outfile);
michael@0:         exit(1);
michael@0:     }
michael@0:     gz_compress(in, out);
michael@0: 
michael@0:     unlink(file);
michael@0: }
michael@0: 
michael@0: 
michael@0: /* ===========================================================================
michael@0:  * Uncompress the given file and remove the original.
michael@0:  */
michael@0: void file_uncompress(file)
michael@0:     char  *file;
michael@0: {
michael@0:     local char buf[MAX_NAME_LEN];
michael@0:     char *infile, *outfile;
michael@0:     FILE  *out;
michael@0:     gzFile in;
michael@0:     size_t len = strlen(file);
michael@0: 
michael@0:     if (len + strlen(GZ_SUFFIX) >= sizeof(buf)) {
michael@0:         fprintf(stderr, "%s: filename too long\n", prog);
michael@0:         exit(1);
michael@0:     }
michael@0: 
michael@0:     strcpy(buf, file);
michael@0: 
michael@0:     if (len > SUFFIX_LEN && strcmp(file+len-SUFFIX_LEN, GZ_SUFFIX) == 0) {
michael@0:         infile = file;
michael@0:         outfile = buf;
michael@0:         outfile[len-3] = '\0';
michael@0:     } else {
michael@0:         outfile = file;
michael@0:         infile = buf;
michael@0:         strcat(infile, GZ_SUFFIX);
michael@0:     }
michael@0:     in = gzopen(infile, "rb");
michael@0:     if (in == NULL) {
michael@0:         fprintf(stderr, "%s: can't gzopen %s\n", prog, infile);
michael@0:         exit(1);
michael@0:     }
michael@0:     out = fopen(outfile, "wb");
michael@0:     if (out == NULL) {
michael@0:         perror(file);
michael@0:         exit(1);
michael@0:     }
michael@0: 
michael@0:     gz_uncompress(in, out);
michael@0: 
michael@0:     unlink(infile);
michael@0: }
michael@0: 
michael@0: 
michael@0: /* ===========================================================================
michael@0:  * Usage:  minigzip [-c] [-d] [-f] [-h] [-r] [-1 to -9] [files...]
michael@0:  *   -c : write to standard output
michael@0:  *   -d : decompress
michael@0:  *   -f : compress with Z_FILTERED
michael@0:  *   -h : compress with Z_HUFFMAN_ONLY
michael@0:  *   -r : compress with Z_RLE
michael@0:  *   -1 to -9 : compression level
michael@0:  */
michael@0: 
michael@0: int main(argc, argv)
michael@0:     int argc;
michael@0:     char *argv[];
michael@0: {
michael@0:     int copyout = 0;
michael@0:     int uncompr = 0;
michael@0:     gzFile file;
michael@0:     char *bname, outmode[20];
michael@0: 
michael@0:     strcpy(outmode, "wb6 ");
michael@0: 
michael@0:     prog = argv[0];
michael@0:     bname = strrchr(argv[0], '/');
michael@0:     if (bname)
michael@0:       bname++;
michael@0:     else
michael@0:       bname = argv[0];
michael@0:     argc--, argv++;
michael@0: 
michael@0:     if (!strcmp(bname, "gunzip"))
michael@0:       uncompr = 1;
michael@0:     else if (!strcmp(bname, "zcat"))
michael@0:       copyout = uncompr = 1;
michael@0: 
michael@0:     while (argc > 0) {
michael@0:       if (strcmp(*argv, "-c") == 0)
michael@0:         copyout = 1;
michael@0:       else if (strcmp(*argv, "-d") == 0)
michael@0:         uncompr = 1;
michael@0:       else if (strcmp(*argv, "-f") == 0)
michael@0:         outmode[3] = 'f';
michael@0:       else if (strcmp(*argv, "-h") == 0)
michael@0:         outmode[3] = 'h';
michael@0:       else if (strcmp(*argv, "-r") == 0)
michael@0:         outmode[3] = 'R';
michael@0:       else if ((*argv)[0] == '-' && (*argv)[1] >= '1' && (*argv)[1] <= '9' &&
michael@0:                (*argv)[2] == 0)
michael@0:         outmode[2] = (*argv)[1];
michael@0:       else
michael@0:         break;
michael@0:       argc--, argv++;
michael@0:     }
michael@0:     if (outmode[3] == ' ')
michael@0:         outmode[3] = 0;
michael@0:     if (argc == 0) {
michael@0:         SET_BINARY_MODE(stdin);
michael@0:         SET_BINARY_MODE(stdout);
michael@0:         if (uncompr) {
michael@0:             file = gzdopen(fileno(stdin), "rb");
michael@0:             if (file == NULL) error("can't gzdopen stdin");
michael@0:             gz_uncompress(file, stdout);
michael@0:         } else {
michael@0:             file = gzdopen(fileno(stdout), outmode);
michael@0:             if (file == NULL) error("can't gzdopen stdout");
michael@0:             gz_compress(stdin, file);
michael@0:         }
michael@0:     } else {
michael@0:         if (copyout) {
michael@0:             SET_BINARY_MODE(stdout);
michael@0:         }
michael@0:         do {
michael@0:             if (uncompr) {
michael@0:                 if (copyout) {
michael@0:                     file = gzopen(*argv, "rb");
michael@0:                     if (file == NULL)
michael@0:                         fprintf(stderr, "%s: can't gzopen %s\n", prog, *argv);
michael@0:                     else
michael@0:                         gz_uncompress(file, stdout);
michael@0:                 } else {
michael@0:                     file_uncompress(*argv);
michael@0:                 }
michael@0:             } else {
michael@0:                 if (copyout) {
michael@0:                     FILE * in = fopen(*argv, "rb");
michael@0: 
michael@0:                     if (in == NULL) {
michael@0:                         perror(*argv);
michael@0:                     } else {
michael@0:                         file = gzdopen(fileno(stdout), outmode);
michael@0:                         if (file == NULL) error("can't gzdopen stdout");
michael@0: 
michael@0:                         gz_compress(in, file);
michael@0:                     }
michael@0: 
michael@0:                 } else {
michael@0:                     file_compress(*argv, outmode);
michael@0:                 }
michael@0:             }
michael@0:         } while (argv++, --argc);
michael@0:     }
michael@0:     return 0;
michael@0: }