xref: /llvm-project/libc/src/stdio/fopencookie.cpp (revision 91bf0a073951aa1ca4c357967ed5aff891941785)
119a6dd33SSiva Chandra Reddy //===-- Implementation of fopencookie -------------------------------------===//
219a6dd33SSiva Chandra Reddy //
319a6dd33SSiva Chandra Reddy // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
419a6dd33SSiva Chandra Reddy // See https://llvm.org/LICENSE.txt for license information.
519a6dd33SSiva Chandra Reddy // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
619a6dd33SSiva Chandra Reddy //
719a6dd33SSiva Chandra Reddy //===----------------------------------------------------------------------===//
819a6dd33SSiva Chandra Reddy 
919a6dd33SSiva Chandra Reddy #include "src/stdio/fopencookie.h"
105aed6d67SMichael Jones #include "hdr/stdio_macros.h"
115aed6d67SMichael Jones #include "hdr/types/FILE.h"
125aed6d67SMichael Jones #include "hdr/types/cookie_io_functions_t.h"
135aed6d67SMichael Jones #include "hdr/types/off_t.h"
14d06308dfSSiva Chandra Reddy #include "src/__support/CPP/new.h"
1519a6dd33SSiva Chandra Reddy #include "src/__support/File/file.h"
1619a6dd33SSiva Chandra Reddy 
175ff3ff33SPetr Hosek #include "src/__support/macros/config.h"
1804a9c625SMichael Jones #include "src/errno/libc_errno.h"
1919a6dd33SSiva Chandra Reddy 
205ff3ff33SPetr Hosek namespace LIBC_NAMESPACE_DECL {
2119a6dd33SSiva Chandra Reddy 
2219a6dd33SSiva Chandra Reddy namespace {
2319a6dd33SSiva Chandra Reddy 
24b6bc9d72SGuillaume Chatelet class CookieFile : public LIBC_NAMESPACE::File {
2519a6dd33SSiva Chandra Reddy   void *cookie;
2619a6dd33SSiva Chandra Reddy   cookie_io_functions_t ops;
27d06308dfSSiva Chandra Reddy 
28d06308dfSSiva Chandra Reddy   static FileIOResult cookie_write(File *f, const void *data, size_t size);
29d06308dfSSiva Chandra Reddy   static FileIOResult cookie_read(File *f, void *data, size_t size);
307776fba4SMikhail R. Gadelha   static ErrorOr<off_t> cookie_seek(File *f, off_t offset, int whence);
31d06308dfSSiva Chandra Reddy   static int cookie_close(File *f);
32d06308dfSSiva Chandra Reddy 
33d06308dfSSiva Chandra Reddy public:
34d06308dfSSiva Chandra Reddy   CookieFile(void *c, cookie_io_functions_t cops, uint8_t *buffer,
35d06308dfSSiva Chandra Reddy              size_t bufsize, File::ModeFlags mode)
36d06308dfSSiva Chandra Reddy       : File(&cookie_write, &cookie_read, &CookieFile::cookie_seek,
3775d70b73SSiva Chandra Reddy              &cookie_close, buffer, bufsize, 0 /* default buffering mode */,
3875d70b73SSiva Chandra Reddy              true /* File owns buffer */, mode),
39d06308dfSSiva Chandra Reddy         cookie(c), ops(cops) {}
4019a6dd33SSiva Chandra Reddy };
4119a6dd33SSiva Chandra Reddy 
42d06308dfSSiva Chandra Reddy FileIOResult CookieFile::cookie_write(File *f, const void *data, size_t size) {
4319a6dd33SSiva Chandra Reddy   auto cookie_file = reinterpret_cast<CookieFile *>(f);
4419a6dd33SSiva Chandra Reddy   if (cookie_file->ops.write == nullptr)
4519a6dd33SSiva Chandra Reddy     return 0;
46*91bf0a07SMikhail R. Gadelha   return static_cast<size_t>(cookie_file->ops.write(
47*91bf0a07SMikhail R. Gadelha       cookie_file->cookie, reinterpret_cast<const char *>(data), size));
4819a6dd33SSiva Chandra Reddy }
4919a6dd33SSiva Chandra Reddy 
50d06308dfSSiva Chandra Reddy FileIOResult CookieFile::cookie_read(File *f, void *data, size_t size) {
5119a6dd33SSiva Chandra Reddy   auto cookie_file = reinterpret_cast<CookieFile *>(f);
5219a6dd33SSiva Chandra Reddy   if (cookie_file->ops.read == nullptr)
5319a6dd33SSiva Chandra Reddy     return 0;
54*91bf0a07SMikhail R. Gadelha   return static_cast<size_t>(cookie_file->ops.read(
55*91bf0a07SMikhail R. Gadelha       cookie_file->cookie, reinterpret_cast<char *>(data), size));
5619a6dd33SSiva Chandra Reddy }
5719a6dd33SSiva Chandra Reddy 
587776fba4SMikhail R. Gadelha ErrorOr<off_t> CookieFile::cookie_seek(File *f, off_t offset, int whence) {
5919a6dd33SSiva Chandra Reddy   auto cookie_file = reinterpret_cast<CookieFile *>(f);
6019a6dd33SSiva Chandra Reddy   if (cookie_file->ops.seek == nullptr) {
619beb8d11SMichael Jones     return Error(EINVAL);
6219a6dd33SSiva Chandra Reddy   }
6319a6dd33SSiva Chandra Reddy   off64_t offset64 = offset;
6443e52ad5SSiva Chandra Reddy   int result = cookie_file->ops.seek(cookie_file->cookie, &offset64, whence);
6543e52ad5SSiva Chandra Reddy   if (result == 0)
6643e52ad5SSiva Chandra Reddy     return offset64;
6743e52ad5SSiva Chandra Reddy   return -1;
6819a6dd33SSiva Chandra Reddy }
6919a6dd33SSiva Chandra Reddy 
70d06308dfSSiva Chandra Reddy int CookieFile::cookie_close(File *f) {
7119a6dd33SSiva Chandra Reddy   auto cookie_file = reinterpret_cast<CookieFile *>(f);
7219a6dd33SSiva Chandra Reddy   if (cookie_file->ops.close == nullptr)
7319a6dd33SSiva Chandra Reddy     return 0;
7475d70b73SSiva Chandra Reddy   int retval = cookie_file->ops.close(cookie_file->cookie);
7575d70b73SSiva Chandra Reddy   if (retval != 0)
7675d70b73SSiva Chandra Reddy     return retval;
7775d70b73SSiva Chandra Reddy   delete cookie_file;
7875d70b73SSiva Chandra Reddy   return 0;
7919a6dd33SSiva Chandra Reddy }
8019a6dd33SSiva Chandra Reddy 
8119a6dd33SSiva Chandra Reddy } // anonymous namespace
8219a6dd33SSiva Chandra Reddy 
8319a6dd33SSiva Chandra Reddy LLVM_LIBC_FUNCTION(::FILE *, fopencookie,
8419a6dd33SSiva Chandra Reddy                    (void *cookie, const char *mode,
8519a6dd33SSiva Chandra Reddy                     cookie_io_functions_t ops)) {
86d06308dfSSiva Chandra Reddy   uint8_t *buffer;
87d06308dfSSiva Chandra Reddy   {
88d06308dfSSiva Chandra Reddy     AllocChecker ac;
89d06308dfSSiva Chandra Reddy     buffer = new (ac) uint8_t[File::DEFAULT_BUFFER_SIZE];
90d06308dfSSiva Chandra Reddy     if (!ac)
9119a6dd33SSiva Chandra Reddy       return nullptr;
92d06308dfSSiva Chandra Reddy   }
93d06308dfSSiva Chandra Reddy   AllocChecker ac;
94d06308dfSSiva Chandra Reddy   auto *file = new (ac) CookieFile(
95d06308dfSSiva Chandra Reddy       cookie, ops, buffer, File::DEFAULT_BUFFER_SIZE, File::mode_flags(mode));
96d06308dfSSiva Chandra Reddy   if (!ac)
97d06308dfSSiva Chandra Reddy     return nullptr;
9819a6dd33SSiva Chandra Reddy   return reinterpret_cast<::FILE *>(file);
9919a6dd33SSiva Chandra Reddy }
10019a6dd33SSiva Chandra Reddy 
1015ff3ff33SPetr Hosek } // namespace LIBC_NAMESPACE_DECL
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