summaryrefslogtreecommitdiff
path: root/src/fs/virtfs/virtfsrwops.cpp
blob: f44cc6601f56274bb0e31d65726e7bf7db3c8f50 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
/*
 *  The ManaPlus Client
 *  Copyright (C) 2013-2017  The ManaPlus Developers
 *
 *  This file is part of The ManaPlus Client.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/*
 * This code provides a glue layer between PhysicsFS and Simple Directmedia
 *  Layer's (SDL) RWops i/o abstraction.
 *
 * License: this code is public domain. I make no warranty that it is useful,
 *  correct, harmless, or environmentally safe.
 *
 * This particular file may be used however you like, including copying it
 *  verbatim into a closed-source project, exploiting it commercially, and
 *  removing any trace of my name from the source (although I hope you won't
 *  do that). I welcome enhancements and corrections to this file, but I do
 *  not require you to send me patches if you make changes. This code has
 *  NO WARRANTY.
 *
 * Unless otherwise stated, the rest of PhysicsFS falls under the zlib license.
 *  Please see LICENSE.txt in the root of the source tree.
 *
 * SDL falls under the LGPL license. You can get SDL at http://www.libsdl.org/
 *
 *  This file was written by Ryan C. Gordon. (icculus@icculus.org).
 *
 *  Copyright (C) 2012-2017  The ManaPlus Developers
 */

#include "fs/virtfs/virtfsrwops.h"

#include "logger.h"

#include "fs/virtfs/virtfs.h"

#include "utils/fuzzer.h"

#include "debug.h"

#ifdef USE_SDL2
#define RWOPSINT int64_t
#define RWOPSSIZE size_t
#else  // USE_SDL2
#define RWOPSINT int32_t
#define RWOPSSIZE int
#endif  // USE_SDL2

static RWOPSINT virtfsrwops_seek(SDL_RWops *const rw,
                                 const RWOPSINT offset,
                                 const int whence)
{
    if (!rw)
        return -1;
    VirtFile *const handle = static_cast<VirtFile *const>(
        rw->hidden.unknown.data1);
    RWOPSINT pos = 0;

    if (whence == SEEK_SET)
    {
        pos = offset;
    } /* if */
    else if (whence == SEEK_CUR)
    {
        const int64_t current = VirtFs::tell(handle);
        if (current == -1)
        {
            logger->assertLog(
                "virtfsrwops_seek: Can't find position in file.");
            return -1;
        } /* if */

        pos = CAST_S32(current);
        if (static_cast<int64_t>(pos) != current)
        {
            logger->assertLog("virtfsrwops_seek: "
                "Can't fit current file position in an int!");
            return -1;
        } /* if */

        if (offset == 0)  /* this is a "tell" call. We're done. */
            return pos;

        pos += offset;
    } /* else if */
    else if (whence == SEEK_END)
    {
        const int64_t len = VirtFs::fileLength(handle);
        if (len == -1)
        {
            logger->assertLog("virtfsrwops_seek:Can't find end of file.");
            return -1;
        } /* if */

        pos = static_cast<RWOPSINT>(len);
        if (static_cast<int64_t>(pos) != len)
        {
            logger->assertLog("virtfsrwops_seek: "
                "Can't fit end-of-file position in an int!");
            return -1;
        } /* if */

        pos += offset;
    } /* else if */
    else
    {
        logger->assertLog("virtfsrwops_seek: Invalid 'whence' parameter.");
        return -1;
    } /* else */

    if (pos < 0)
    {
        logger->assertLog("virtfsrwops_seek: "
            "Attempt to seek past start of file.");
        return -1;
    } /* if */

    if (!VirtFs::seek(handle, static_cast<uint64_t>(pos)))
    {
        logger->assertLog("virtfsrwops_seek: seek error.");
        return -1;
    } /* if */

    return pos;
} /* virtfsrwops_seek */

static RWOPSSIZE virtfsrwops_read(SDL_RWops *const rw,
                                  void *const ptr,
                                  const RWOPSSIZE size,
                                  const RWOPSSIZE maxnum)
{
    if (!rw)
        return 0;
    VirtFile *const handle = static_cast<VirtFile *const>(
        rw->hidden.unknown.data1);
    const int64_t rc = VirtFs::read(handle, ptr,
        CAST_U32(size),
        CAST_U32(maxnum));
    if (rc != static_cast<int64_t>(maxnum))
    {
        if (!VirtFs::eof(handle)) /* not EOF? Must be an error. */
        {
            logger->assertLog("virtfsrwops_seek: read error.");
        }
    } /* if */

    return CAST_S32(rc);
} /* virtfsrwops_read */

static RWOPSSIZE virtfsrwops_write(SDL_RWops *const rw,
                                   const void *const ptr,
                                   const RWOPSSIZE size,
                                   const RWOPSSIZE num)
{
    if (!rw)
        return 0;
    VirtFile *const handle = static_cast<VirtFile *const>(
        rw->hidden.unknown.data1);
    const int64_t rc = VirtFs::write(handle, ptr,
        CAST_U32(size),
        CAST_U32(num));
    if (rc != static_cast<int64_t>(num))
    {
        logger->assertLog("virtfsrwops_seek: write error.");
    }

    return CAST_S32(rc);
} /* virtfsrwops_write */

static int virtfsrwops_close(SDL_RWops *const rw)
{
    if (!rw)
        return 0;
    VirtFile *const handle = static_cast<VirtFile*>(
        rw->hidden.unknown.data1);
    if (!VirtFs::close(handle))
    {
        logger->assertLog("virtfsrwops_seek: close error.");
        return -1;
    } /* if */

    SDL_FreeRW(rw);
    return 0;
} /* virtfsrwops_close */

#ifdef USE_SDL2
static RWOPSINT virtfsrwops_size(SDL_RWops *const rw)
{
    VirtFile *const handle = static_cast<VirtFile *const>(
        rw->hidden.unknown.data1);
    return VirtFs::fileLength(handle);
} /* virtfsrwops_size */
#endif  // USE_SDL2

static SDL_RWops *create_rwops(VirtFile *const file)
{
    SDL_RWops *retval = nullptr;

    if (!file)
    {
        logger->assertLog("virtfsrwops_seek: create rwops error.");
    }
    else
    {
        retval = SDL_AllocRW();
        if (retval)
        {
#ifdef USE_SDL2
            retval->size  = &virtfsrwops_size;
#endif  // USE_SDL2

            retval->seek  = &virtfsrwops_seek;
            retval->read  = &virtfsrwops_read;
            retval->write = &virtfsrwops_write;
            retval->close = &virtfsrwops_close;
            retval->hidden.unknown.data1 = file;
        } /* if */
    } /* else */

    return retval;
} /* create_rwops */

SDL_RWops *VirtFs::MakeRWops(VirtFile *const handle)
{
    SDL_RWops *retval = nullptr;
    if (!handle)
    {
        logger->assertLog("virtfsrwops_seek: NULL pointer passed to "
            "RWopsmakeRWops().");
    }
    else
    {
        retval = create_rwops(handle);
    }

    return retval;
} /* RWopsmakeRWops */

#ifdef __APPLE__
static bool checkFilePath(const std::string &restrict fname)
{
    if (fname.empty())
        return false;
    if (!VirtFs::exists(fname) || VirtFs::isDirectory(fname))
        return false;
    return true;
}
#endif  // __APPLE__

SDL_RWops *VirtFs::RWopsOpenRead(const std::string &restrict fname)
{
    BLOCK_START("RWopsopenRead")
#ifdef __APPLE__
    if (!checkFilePath(fname))
        return nullptr;
#endif  // __APPLE__
#ifdef USE_FUZZER
    if (Fuzzer::conditionTerminate(fname))
        return nullptr;
#endif  // USE_FUZZER
#ifdef USE_PROFILER

    SDL_RWops *const ret = create_rwops(VirtFs::openRead(fname));

    BLOCK_END("RWopsopenRead")
    return ret;
#else  // USE_PROFILER

    return create_rwops(VirtFs::openRead(fname));
#endif  // USE_PROFILER
} /* RWopsopenRead */

SDL_RWops *VirtFs::RWopsOpenWrite(const std::string &restrict fname)
{
#ifdef __APPLE__
    if (!checkFilePath(fname))
        return nullptr;
#endif  // __APPLE__

    return create_rwops(VirtFs::openWrite(fname));
} /* RWopsopenWrite */

SDL_RWops *VirtFs::RWopsOpenAppend(const std::string &restrict fname)
{
#ifdef __APPLE__
    if (!checkFilePath(fname))
        return nullptr;
#endif  // __APPLE__

    return create_rwops(VirtFs::openAppend(fname));
} /* RWopsopenAppend */

/* end of virtfsrwops.c ... */