9e052883 |
1 | /* |
2 | * |
3 | * Copyright (c) 1997 |
4 | * Christian Michelsen Research AS |
5 | * Advanced Computing |
6 | * Fantoftvegen 38, 5036 BERGEN, Norway |
7 | * http://www.cmr.no |
8 | * |
9 | * Permission to use, copy, modify, distribute and sell this software |
10 | * and its documentation for any purpose is hereby granted without fee, |
11 | * provided that the above copyright notice appear in all copies and |
12 | * that both that copyright notice and this permission notice appear |
13 | * in supporting documentation. Christian Michelsen Research AS makes no |
14 | * representations about the suitability of this software for any |
15 | * purpose. It is provided "as is" without express or implied warranty. |
16 | * |
17 | */ |
18 | |
19 | #ifndef ZSTREAM__H |
20 | #define ZSTREAM__H |
21 | |
22 | /* |
23 | * zstream.h - C++ interface to the 'zlib' general purpose compression library |
24 | * $Id: zstream.h 1.1 1997-06-25 12:00:56+02 tyge Exp tyge $ |
25 | */ |
26 | |
27 | #include <strstream.h> |
28 | #include <string.h> |
29 | #include <stdio.h> |
30 | #include "zlib.h" |
31 | |
32 | #if defined(_WIN32) |
33 | # include <fcntl.h> |
34 | # include <io.h> |
35 | # define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY) |
36 | #else |
37 | # define SET_BINARY_MODE(file) |
38 | #endif |
39 | |
40 | class zstringlen { |
41 | public: |
42 | zstringlen(class izstream&); |
43 | zstringlen(class ozstream&, const char*); |
44 | size_t value() const { return val.word; } |
45 | private: |
46 | struct Val { unsigned char byte; size_t word; } val; |
47 | }; |
48 | |
49 | // ----------------------------- izstream ----------------------------- |
50 | |
51 | class izstream |
52 | { |
53 | public: |
54 | izstream() : m_fp(0) {} |
55 | izstream(FILE* fp) : m_fp(0) { open(fp); } |
56 | izstream(const char* name) : m_fp(0) { open(name); } |
57 | ~izstream() { close(); } |
58 | |
59 | /* Opens a gzip (.gz) file for reading. |
60 | * open() can be used to read a file which is not in gzip format; |
61 | * in this case read() will directly read from the file without |
62 | * decompression. errno can be checked to distinguish two error |
63 | * cases (if errno is zero, the zlib error is Z_MEM_ERROR). |
64 | */ |
65 | void open(const char* name) { |
66 | if (m_fp) close(); |
67 | m_fp = ::gzopen(name, "rb"); |
68 | } |
69 | |
70 | void open(FILE* fp) { |
71 | SET_BINARY_MODE(fp); |
72 | if (m_fp) close(); |
73 | m_fp = ::gzdopen(fileno(fp), "rb"); |
74 | } |
75 | |
76 | /* Flushes all pending input if necessary, closes the compressed file |
77 | * and deallocates all the (de)compression state. The return value is |
78 | * the zlib error number (see function error() below). |
79 | */ |
80 | int close() { |
81 | int r = ::gzclose(m_fp); |
82 | m_fp = 0; return r; |
83 | } |
84 | |
85 | /* Binary read the given number of bytes from the compressed file. |
86 | */ |
87 | int read(void* buf, size_t len) { |
88 | return ::gzread(m_fp, buf, len); |
89 | } |
90 | |
91 | /* Returns the error message for the last error which occurred on the |
92 | * given compressed file. errnum is set to zlib error number. If an |
93 | * error occurred in the file system and not in the compression library, |
94 | * errnum is set to Z_ERRNO and the application may consult errno |
95 | * to get the exact error code. |
96 | */ |
97 | const char* error(int* errnum) { |
98 | return ::gzerror(m_fp, errnum); |
99 | } |
100 | |
101 | gzFile fp() { return m_fp; } |
102 | |
103 | private: |
104 | gzFile m_fp; |
105 | }; |
106 | |
107 | /* |
108 | * Binary read the given (array of) object(s) from the compressed file. |
109 | * If the input file was not in gzip format, read() copies the objects number |
110 | * of bytes into the buffer. |
111 | * returns the number of uncompressed bytes actually read |
112 | * (0 for end of file, -1 for error). |
113 | */ |
114 | template <class T, class Items> |
115 | inline int read(izstream& zs, T* x, Items items) { |
116 | return ::gzread(zs.fp(), x, items*sizeof(T)); |
117 | } |
118 | |
119 | /* |
120 | * Binary input with the '>' operator. |
121 | */ |
122 | template <class T> |
123 | inline izstream& operator>(izstream& zs, T& x) { |
124 | ::gzread(zs.fp(), &x, sizeof(T)); |
125 | return zs; |
126 | } |
127 | |
128 | |
129 | inline zstringlen::zstringlen(izstream& zs) { |
130 | zs > val.byte; |
131 | if (val.byte == 255) zs > val.word; |
132 | else val.word = val.byte; |
133 | } |
134 | |
135 | /* |
136 | * Read length of string + the string with the '>' operator. |
137 | */ |
138 | inline izstream& operator>(izstream& zs, char* x) { |
139 | zstringlen len(zs); |
140 | ::gzread(zs.fp(), x, len.value()); |
141 | x[len.value()] = '\0'; |
142 | return zs; |
143 | } |
144 | |
145 | inline char* read_string(izstream& zs) { |
146 | zstringlen len(zs); |
147 | char* x = new char[len.value()+1]; |
148 | ::gzread(zs.fp(), x, len.value()); |
149 | x[len.value()] = '\0'; |
150 | return x; |
151 | } |
152 | |
153 | // ----------------------------- ozstream ----------------------------- |
154 | |
155 | class ozstream |
156 | { |
157 | public: |
158 | ozstream() : m_fp(0), m_os(0) { |
159 | } |
160 | ozstream(FILE* fp, int level = Z_DEFAULT_COMPRESSION) |
161 | : m_fp(0), m_os(0) { |
162 | open(fp, level); |
163 | } |
164 | ozstream(const char* name, int level = Z_DEFAULT_COMPRESSION) |
165 | : m_fp(0), m_os(0) { |
166 | open(name, level); |
167 | } |
168 | ~ozstream() { |
169 | close(); |
170 | } |
171 | |
172 | /* Opens a gzip (.gz) file for writing. |
173 | * The compression level parameter should be in 0..9 |
174 | * errno can be checked to distinguish two error cases |
175 | * (if errno is zero, the zlib error is Z_MEM_ERROR). |
176 | */ |
177 | void open(const char* name, int level = Z_DEFAULT_COMPRESSION) { |
178 | char mode[4] = "wb\0"; |
179 | if (level != Z_DEFAULT_COMPRESSION) mode[2] = '0'+level; |
180 | if (m_fp) close(); |
181 | m_fp = ::gzopen(name, mode); |
182 | } |
183 | |
184 | /* open from a FILE pointer. |
185 | */ |
186 | void open(FILE* fp, int level = Z_DEFAULT_COMPRESSION) { |
187 | SET_BINARY_MODE(fp); |
188 | char mode[4] = "wb\0"; |
189 | if (level != Z_DEFAULT_COMPRESSION) mode[2] = '0'+level; |
190 | if (m_fp) close(); |
191 | m_fp = ::gzdopen(fileno(fp), mode); |
192 | } |
193 | |
194 | /* Flushes all pending output if necessary, closes the compressed file |
195 | * and deallocates all the (de)compression state. The return value is |
196 | * the zlib error number (see function error() below). |
197 | */ |
198 | int close() { |
199 | if (m_os) { |
200 | ::gzwrite(m_fp, m_os->str(), m_os->pcount()); |
201 | delete[] m_os->str(); delete m_os; m_os = 0; |
202 | } |
203 | int r = ::gzclose(m_fp); m_fp = 0; return r; |
204 | } |
205 | |
206 | /* Binary write the given number of bytes into the compressed file. |
207 | */ |
208 | int write(const void* buf, size_t len) { |
209 | return ::gzwrite(m_fp, (voidp) buf, len); |
210 | } |
211 | |
212 | /* Flushes all pending output into the compressed file. The parameter |
213 | * _flush is as in the deflate() function. The return value is the zlib |
214 | * error number (see function gzerror below). flush() returns Z_OK if |
215 | * the flush_ parameter is Z_FINISH and all output could be flushed. |
216 | * flush() should be called only when strictly necessary because it can |
217 | * degrade compression. |
218 | */ |
219 | int flush(int _flush) { |
220 | os_flush(); |
221 | return ::gzflush(m_fp, _flush); |
222 | } |
223 | |
224 | /* Returns the error message for the last error which occurred on the |
225 | * given compressed file. errnum is set to zlib error number. If an |
226 | * error occurred in the file system and not in the compression library, |
227 | * errnum is set to Z_ERRNO and the application may consult errno |
228 | * to get the exact error code. |
229 | */ |
230 | const char* error(int* errnum) { |
231 | return ::gzerror(m_fp, errnum); |
232 | } |
233 | |
234 | gzFile fp() { return m_fp; } |
235 | |
236 | ostream& os() { |
237 | if (m_os == 0) m_os = new ostrstream; |
238 | return *m_os; |
239 | } |
240 | |
241 | void os_flush() { |
242 | if (m_os && m_os->pcount()>0) { |
243 | ostrstream* oss = new ostrstream; |
244 | oss->fill(m_os->fill()); |
245 | oss->flags(m_os->flags()); |
246 | oss->precision(m_os->precision()); |
247 | oss->width(m_os->width()); |
248 | ::gzwrite(m_fp, m_os->str(), m_os->pcount()); |
249 | delete[] m_os->str(); delete m_os; m_os = oss; |
250 | } |
251 | } |
252 | |
253 | private: |
254 | gzFile m_fp; |
255 | ostrstream* m_os; |
256 | }; |
257 | |
258 | /* |
259 | * Binary write the given (array of) object(s) into the compressed file. |
260 | * returns the number of uncompressed bytes actually written |
261 | * (0 in case of error). |
262 | */ |
263 | template <class T, class Items> |
264 | inline int write(ozstream& zs, const T* x, Items items) { |
265 | return ::gzwrite(zs.fp(), (voidp) x, items*sizeof(T)); |
266 | } |
267 | |
268 | /* |
269 | * Binary output with the '<' operator. |
270 | */ |
271 | template <class T> |
272 | inline ozstream& operator<(ozstream& zs, const T& x) { |
273 | ::gzwrite(zs.fp(), (voidp) &x, sizeof(T)); |
274 | return zs; |
275 | } |
276 | |
277 | inline zstringlen::zstringlen(ozstream& zs, const char* x) { |
278 | val.byte = 255; val.word = ::strlen(x); |
279 | if (val.word < 255) zs < (val.byte = val.word); |
280 | else zs < val; |
281 | } |
282 | |
283 | /* |
284 | * Write length of string + the string with the '<' operator. |
285 | */ |
286 | inline ozstream& operator<(ozstream& zs, const char* x) { |
287 | zstringlen len(zs, x); |
288 | ::gzwrite(zs.fp(), (voidp) x, len.value()); |
289 | return zs; |
290 | } |
291 | |
292 | #ifdef _MSC_VER |
293 | inline ozstream& operator<(ozstream& zs, char* const& x) { |
294 | return zs < (const char*) x; |
295 | } |
296 | #endif |
297 | |
298 | /* |
299 | * Ascii write with the << operator; |
300 | */ |
301 | template <class T> |
302 | inline ostream& operator<<(ozstream& zs, const T& x) { |
303 | zs.os_flush(); |
304 | return zs.os() << x; |
305 | } |
306 | |
307 | #endif |