1 //===-- Implementation of fopencookie -------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "src/stdio/fopencookie.h"
10 #include "hdr/stdio_macros.h"
11 #include "hdr/types/FILE.h"
12 #include "hdr/types/cookie_io_functions_t.h"
13 #include "hdr/types/off_t.h"
14 #include "src/__support/CPP/new.h"
15 #include "src/__support/File/file.h"
16
17 #include "src/__support/macros/config.h"
18 #include "src/errno/libc_errno.h"
19
20 namespace LIBC_NAMESPACE_DECL {
21
22 namespace {
23
24 class CookieFile : public LIBC_NAMESPACE::File {
25 void *cookie;
26 cookie_io_functions_t ops;
27
28 static FileIOResult cookie_write(File *f, const void *data, size_t size);
29 static FileIOResult cookie_read(File *f, void *data, size_t size);
30 static ErrorOr<off_t> cookie_seek(File *f, off_t offset, int whence);
31 static int cookie_close(File *f);
32
33 public:
CookieFile(void * c,cookie_io_functions_t cops,uint8_t * buffer,size_t bufsize,File::ModeFlags mode)34 CookieFile(void *c, cookie_io_functions_t cops, uint8_t *buffer,
35 size_t bufsize, File::ModeFlags mode)
36 : File(&cookie_write, &cookie_read, &CookieFile::cookie_seek,
37 &cookie_close, buffer, bufsize, 0 /* default buffering mode */,
38 true /* File owns buffer */, mode),
39 cookie(c), ops(cops) {}
40 };
41
cookie_write(File * f,const void * data,size_t size)42 FileIOResult CookieFile::cookie_write(File *f, const void *data, size_t size) {
43 auto cookie_file = reinterpret_cast<CookieFile *>(f);
44 if (cookie_file->ops.write == nullptr)
45 return 0;
46 return static_cast<size_t>(cookie_file->ops.write(
47 cookie_file->cookie, reinterpret_cast<const char *>(data), size));
48 }
49
cookie_read(File * f,void * data,size_t size)50 FileIOResult CookieFile::cookie_read(File *f, void *data, size_t size) {
51 auto cookie_file = reinterpret_cast<CookieFile *>(f);
52 if (cookie_file->ops.read == nullptr)
53 return 0;
54 return static_cast<size_t>(cookie_file->ops.read(
55 cookie_file->cookie, reinterpret_cast<char *>(data), size));
56 }
57
cookie_seek(File * f,off_t offset,int whence)58 ErrorOr<off_t> CookieFile::cookie_seek(File *f, off_t offset, int whence) {
59 auto cookie_file = reinterpret_cast<CookieFile *>(f);
60 if (cookie_file->ops.seek == nullptr) {
61 return Error(EINVAL);
62 }
63 off64_t offset64 = offset;
64 int result = cookie_file->ops.seek(cookie_file->cookie, &offset64, whence);
65 if (result == 0)
66 return offset64;
67 return -1;
68 }
69
cookie_close(File * f)70 int CookieFile::cookie_close(File *f) {
71 auto cookie_file = reinterpret_cast<CookieFile *>(f);
72 if (cookie_file->ops.close == nullptr)
73 return 0;
74 int retval = cookie_file->ops.close(cookie_file->cookie);
75 if (retval != 0)
76 return retval;
77 delete cookie_file;
78 return 0;
79 }
80
81 } // anonymous namespace
82
83 LLVM_LIBC_FUNCTION(::FILE *, fopencookie,
84 (void *cookie, const char *mode,
85 cookie_io_functions_t ops)) {
86 uint8_t *buffer;
87 {
88 AllocChecker ac;
89 buffer = new (ac) uint8_t[File::DEFAULT_BUFFER_SIZE];
90 if (!ac)
91 return nullptr;
92 }
93 AllocChecker ac;
94 auto *file = new (ac) CookieFile(
95 cookie, ops, buffer, File::DEFAULT_BUFFER_SIZE, File::mode_flags(mode));
96 if (!ac)
97 return nullptr;
98 return reinterpret_cast<::FILE *>(file);
99 }
100
101 } // namespace LIBC_NAMESPACE_DECL
102