diff options
Diffstat (limited to 'lib/libz/minigzip.c')
-rw-r--r-- | lib/libz/minigzip.c | 440 |
1 files changed, 440 insertions, 0 deletions
diff --git a/lib/libz/minigzip.c b/lib/libz/minigzip.c new file mode 100644 index 0000000..9825ccc --- /dev/null +++ b/lib/libz/minigzip.c @@ -0,0 +1,440 @@ +/* minigzip.c -- simulate gzip using the zlib compression library + * Copyright (C) 1995-2006, 2010 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 + +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; +} |