Chris@4: /*
Chris@4:  *
Chris@4:  * Copyright (c) 1997
Chris@4:  * Christian Michelsen Research AS
Chris@4:  * Advanced Computing
Chris@4:  * Fantoftvegen 38, 5036 BERGEN, Norway
Chris@4:  * http://www.cmr.no
Chris@4:  *
Chris@4:  * Permission to use, copy, modify, distribute and sell this software
Chris@4:  * and its documentation for any purpose is hereby granted without fee,
Chris@4:  * provided that the above copyright notice appear in all copies and
Chris@4:  * that both that copyright notice and this permission notice appear
Chris@4:  * in supporting documentation.  Christian Michelsen Research AS makes no
Chris@4:  * representations about the suitability of this software for any
Chris@4:  * purpose.  It is provided "as is" without express or implied warranty.
Chris@4:  *
Chris@4:  */
Chris@4: 
Chris@4: #ifndef ZSTREAM__H
Chris@4: #define ZSTREAM__H
Chris@4: 
Chris@4: /*
Chris@4:  * zstream.h - C++ interface to the 'zlib' general purpose compression library
Chris@4:  * $Id: zstream.h 1.1 1997-06-25 12:00:56+02 tyge Exp tyge $
Chris@4:  */
Chris@4: 
Chris@4: #include <strstream.h>
Chris@4: #include <string.h>
Chris@4: #include <stdio.h>
Chris@4: #include "zlib.h"
Chris@4: 
Chris@4: #if defined(_WIN32)
Chris@4: #   include <fcntl.h>
Chris@4: #   include <io.h>
Chris@4: #   define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
Chris@4: #else
Chris@4: #   define SET_BINARY_MODE(file)
Chris@4: #endif
Chris@4: 
Chris@4: class zstringlen {
Chris@4: public:
Chris@4:     zstringlen(class izstream&);
Chris@4:     zstringlen(class ozstream&, const char*);
Chris@4:     size_t value() const { return val.word; }
Chris@4: private:
Chris@4:     struct Val { unsigned char byte; size_t word; } val;
Chris@4: };
Chris@4: 
Chris@4: //  ----------------------------- izstream -----------------------------
Chris@4: 
Chris@4: class izstream
Chris@4: {
Chris@4:     public:
Chris@4:         izstream() : m_fp(0) {}
Chris@4:         izstream(FILE* fp) : m_fp(0) { open(fp); }
Chris@4:         izstream(const char* name) : m_fp(0) { open(name); }
Chris@4:         ~izstream() { close(); }
Chris@4: 
Chris@4:         /* Opens a gzip (.gz) file for reading.
Chris@4:          * open() can be used to read a file which is not in gzip format;
Chris@4:          * in this case read() will directly read from the file without
Chris@4:          * decompression. errno can be checked to distinguish two error
Chris@4:          * cases (if errno is zero, the zlib error is Z_MEM_ERROR).
Chris@4:          */
Chris@4:         void open(const char* name) {
Chris@4:             if (m_fp) close();
Chris@4:             m_fp = ::gzopen(name, "rb");
Chris@4:         }
Chris@4: 
Chris@4:         void open(FILE* fp) {
Chris@4:             SET_BINARY_MODE(fp);
Chris@4:             if (m_fp) close();
Chris@4:             m_fp = ::gzdopen(fileno(fp), "rb");
Chris@4:         }
Chris@4: 
Chris@4:         /* Flushes all pending input if necessary, closes the compressed file
Chris@4:          * and deallocates all the (de)compression state. The return value is
Chris@4:          * the zlib error number (see function error() below).
Chris@4:          */
Chris@4:         int close() {
Chris@4:             int r = ::gzclose(m_fp);
Chris@4:             m_fp = 0; return r;
Chris@4:         }
Chris@4: 
Chris@4:         /* Binary read the given number of bytes from the compressed file.
Chris@4:          */
Chris@4:         int read(void* buf, size_t len) {
Chris@4:             return ::gzread(m_fp, buf, len);
Chris@4:         }
Chris@4: 
Chris@4:         /* Returns the error message for the last error which occurred on the
Chris@4:          * given compressed file. errnum is set to zlib error number. If an
Chris@4:          * error occurred in the file system and not in the compression library,
Chris@4:          * errnum is set to Z_ERRNO and the application may consult errno
Chris@4:          * to get the exact error code.
Chris@4:          */
Chris@4:         const char* error(int* errnum) {
Chris@4:             return ::gzerror(m_fp, errnum);
Chris@4:         }
Chris@4: 
Chris@4:         gzFile fp() { return m_fp; }
Chris@4: 
Chris@4:     private:
Chris@4:         gzFile m_fp;
Chris@4: };
Chris@4: 
Chris@4: /*
Chris@4:  * Binary read the given (array of) object(s) from the compressed file.
Chris@4:  * If the input file was not in gzip format, read() copies the objects number
Chris@4:  * of bytes into the buffer.
Chris@4:  * returns the number of uncompressed bytes actually read
Chris@4:  * (0 for end of file, -1 for error).
Chris@4:  */
Chris@4: template <class T, class Items>
Chris@4: inline int read(izstream& zs, T* x, Items items) {
Chris@4:     return ::gzread(zs.fp(), x, items*sizeof(T));
Chris@4: }
Chris@4: 
Chris@4: /*
Chris@4:  * Binary input with the '>' operator.
Chris@4:  */
Chris@4: template <class T>
Chris@4: inline izstream& operator>(izstream& zs, T& x) {
Chris@4:     ::gzread(zs.fp(), &x, sizeof(T));
Chris@4:     return zs;
Chris@4: }
Chris@4: 
Chris@4: 
Chris@4: inline zstringlen::zstringlen(izstream& zs) {
Chris@4:     zs > val.byte;
Chris@4:     if (val.byte == 255) zs > val.word;
Chris@4:     else val.word = val.byte;
Chris@4: }
Chris@4: 
Chris@4: /*
Chris@4:  * Read length of string + the string with the '>' operator.
Chris@4:  */
Chris@4: inline izstream& operator>(izstream& zs, char* x) {
Chris@4:     zstringlen len(zs);
Chris@4:     ::gzread(zs.fp(), x, len.value());
Chris@4:     x[len.value()] = '\0';
Chris@4:     return zs;
Chris@4: }
Chris@4: 
Chris@4: inline char* read_string(izstream& zs) {
Chris@4:     zstringlen len(zs);
Chris@4:     char* x = new char[len.value()+1];
Chris@4:     ::gzread(zs.fp(), x, len.value());
Chris@4:     x[len.value()] = '\0';
Chris@4:     return x;
Chris@4: }
Chris@4: 
Chris@4: // ----------------------------- ozstream -----------------------------
Chris@4: 
Chris@4: class ozstream
Chris@4: {
Chris@4:     public:
Chris@4:         ozstream() : m_fp(0), m_os(0) {
Chris@4:         }
Chris@4:         ozstream(FILE* fp, int level = Z_DEFAULT_COMPRESSION)
Chris@4:             : m_fp(0), m_os(0) {
Chris@4:             open(fp, level);
Chris@4:         }
Chris@4:         ozstream(const char* name, int level = Z_DEFAULT_COMPRESSION)
Chris@4:             : m_fp(0), m_os(0) {
Chris@4:             open(name, level);
Chris@4:         }
Chris@4:         ~ozstream() {
Chris@4:             close();
Chris@4:         }
Chris@4: 
Chris@4:         /* Opens a gzip (.gz) file for writing.
Chris@4:          * The compression level parameter should be in 0..9
Chris@4:          * errno can be checked to distinguish two error cases
Chris@4:          * (if errno is zero, the zlib error is Z_MEM_ERROR).
Chris@4:          */
Chris@4:         void open(const char* name, int level = Z_DEFAULT_COMPRESSION) {
Chris@4:             char mode[4] = "wb\0";
Chris@4:             if (level != Z_DEFAULT_COMPRESSION) mode[2] = '0'+level;
Chris@4:             if (m_fp) close();
Chris@4:             m_fp = ::gzopen(name, mode);
Chris@4:         }
Chris@4: 
Chris@4:         /* open from a FILE pointer.
Chris@4:          */
Chris@4:         void open(FILE* fp, int level = Z_DEFAULT_COMPRESSION) {
Chris@4:             SET_BINARY_MODE(fp);
Chris@4:             char mode[4] = "wb\0";
Chris@4:             if (level != Z_DEFAULT_COMPRESSION) mode[2] = '0'+level;
Chris@4:             if (m_fp) close();
Chris@4:             m_fp = ::gzdopen(fileno(fp), mode);
Chris@4:         }
Chris@4: 
Chris@4:         /* Flushes all pending output if necessary, closes the compressed file
Chris@4:          * and deallocates all the (de)compression state. The return value is
Chris@4:          * the zlib error number (see function error() below).
Chris@4:          */
Chris@4:         int close() {
Chris@4:             if (m_os) {
Chris@4:                 ::gzwrite(m_fp, m_os->str(), m_os->pcount());
Chris@4:                 delete[] m_os->str(); delete m_os; m_os = 0;
Chris@4:             }
Chris@4:             int r = ::gzclose(m_fp); m_fp = 0; return r;
Chris@4:         }
Chris@4: 
Chris@4:         /* Binary write the given number of bytes into the compressed file.
Chris@4:          */
Chris@4:         int write(const void* buf, size_t len) {
Chris@4:             return ::gzwrite(m_fp, (voidp) buf, len);
Chris@4:         }
Chris@4: 
Chris@4:         /* Flushes all pending output into the compressed file. The parameter
Chris@4:          * _flush is as in the deflate() function. The return value is the zlib
Chris@4:          * error number (see function gzerror below). flush() returns Z_OK if
Chris@4:          * the flush_ parameter is Z_FINISH and all output could be flushed.
Chris@4:          * flush() should be called only when strictly necessary because it can
Chris@4:          * degrade compression.
Chris@4:          */
Chris@4:         int flush(int _flush) {
Chris@4:             os_flush();
Chris@4:             return ::gzflush(m_fp, _flush);
Chris@4:         }
Chris@4: 
Chris@4:         /* Returns the error message for the last error which occurred on the
Chris@4:          * given compressed file. errnum is set to zlib error number. If an
Chris@4:          * error occurred in the file system and not in the compression library,
Chris@4:          * errnum is set to Z_ERRNO and the application may consult errno
Chris@4:          * to get the exact error code.
Chris@4:          */
Chris@4:         const char* error(int* errnum) {
Chris@4:             return ::gzerror(m_fp, errnum);
Chris@4:         }
Chris@4: 
Chris@4:         gzFile fp() { return m_fp; }
Chris@4: 
Chris@4:         ostream& os() {
Chris@4:             if (m_os == 0) m_os = new ostrstream;
Chris@4:             return *m_os;
Chris@4:         }
Chris@4: 
Chris@4:         void os_flush() {
Chris@4:             if (m_os && m_os->pcount()>0) {
Chris@4:                 ostrstream* oss = new ostrstream;
Chris@4:                 oss->fill(m_os->fill());
Chris@4:                 oss->flags(m_os->flags());
Chris@4:                 oss->precision(m_os->precision());
Chris@4:                 oss->width(m_os->width());
Chris@4:                 ::gzwrite(m_fp, m_os->str(), m_os->pcount());
Chris@4:                 delete[] m_os->str(); delete m_os; m_os = oss;
Chris@4:             }
Chris@4:         }
Chris@4: 
Chris@4:     private:
Chris@4:         gzFile m_fp;
Chris@4:         ostrstream* m_os;
Chris@4: };
Chris@4: 
Chris@4: /*
Chris@4:  * Binary write the given (array of) object(s) into the compressed file.
Chris@4:  * returns the number of uncompressed bytes actually written
Chris@4:  * (0 in case of error).
Chris@4:  */
Chris@4: template <class T, class Items>
Chris@4: inline int write(ozstream& zs, const T* x, Items items) {
Chris@4:     return ::gzwrite(zs.fp(), (voidp) x, items*sizeof(T));
Chris@4: }
Chris@4: 
Chris@4: /*
Chris@4:  * Binary output with the '<' operator.
Chris@4:  */
Chris@4: template <class T>
Chris@4: inline ozstream& operator<(ozstream& zs, const T& x) {
Chris@4:     ::gzwrite(zs.fp(), (voidp) &x, sizeof(T));
Chris@4:     return zs;
Chris@4: }
Chris@4: 
Chris@4: inline zstringlen::zstringlen(ozstream& zs, const char* x) {
Chris@4:     val.byte = 255;  val.word = ::strlen(x);
Chris@4:     if (val.word < 255) zs < (val.byte = val.word);
Chris@4:     else zs < val;
Chris@4: }
Chris@4: 
Chris@4: /*
Chris@4:  * Write length of string + the string with the '<' operator.
Chris@4:  */
Chris@4: inline ozstream& operator<(ozstream& zs, const char* x) {
Chris@4:     zstringlen len(zs, x);
Chris@4:     ::gzwrite(zs.fp(), (voidp) x, len.value());
Chris@4:     return zs;
Chris@4: }
Chris@4: 
Chris@4: #ifdef _MSC_VER
Chris@4: inline ozstream& operator<(ozstream& zs, char* const& x) {
Chris@4:     return zs < (const char*) x;
Chris@4: }
Chris@4: #endif
Chris@4: 
Chris@4: /*
Chris@4:  * Ascii write with the << operator;
Chris@4:  */
Chris@4: template <class T>
Chris@4: inline ostream& operator<<(ozstream& zs, const T& x) {
Chris@4:     zs.os_flush();
Chris@4:     return zs.os() << x;
Chris@4: }
Chris@4: 
Chris@4: #endif