xref: /llvm-project/lldb/source/Host/posix/FileSystemPosix.cpp (revision 7edeeab5e0023dabd6003d6f113575a5b5b6c83b)
1 //===-- FileSystemPosix.cpp -----------------------------------------------===//
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 "lldb/Host/FileSystem.h"
10 
11 // C includes
12 #include <fcntl.h>
13 #include <unistd.h>
14 
15 // lldb Includes
16 #include "lldb/Host/Host.h"
17 #include "lldb/Utility/Status.h"
18 #include "lldb/Utility/StreamString.h"
19 
20 #include "llvm/Support/Errno.h"
21 #include "llvm/Support/FileSystem.h"
22 
23 using namespace lldb;
24 using namespace lldb_private;
25 
26 const char *FileSystem::DEV_NULL = "/dev/null";
27 
28 Status FileSystem::Symlink(const FileSpec &src, const FileSpec &dst) {
29   Status error;
30   if (::symlink(dst.GetPath().c_str(), src.GetPath().c_str()) == -1)
31     return Status::FromErrno();
32   return error;
33 }
34 
35 Status FileSystem::Readlink(const FileSpec &src, FileSpec &dst) {
36   Status error;
37   char buf[PATH_MAX];
38   ssize_t count = ::readlink(src.GetPath().c_str(), buf, sizeof(buf) - 1);
39   if (count < 0)
40     return Status::FromErrno();
41 
42   buf[count] = '\0'; // Success
43   dst.SetFile(buf, FileSpec::Style::native);
44 
45   return error;
46 }
47 
48 Status FileSystem::ResolveSymbolicLink(const FileSpec &src, FileSpec &dst) {
49   char resolved_path[PATH_MAX];
50   if (!src.GetPath(resolved_path, sizeof(resolved_path))) {
51     return Status::FromErrorStringWithFormat(
52         "Couldn't get the canonical path for %s", src.GetPath().c_str());
53   }
54 
55   char real_path[PATH_MAX + 1];
56   if (realpath(resolved_path, real_path) == nullptr) {
57     return Status::FromErrno();
58   }
59 
60   dst = FileSpec(real_path);
61 
62   return Status();
63 }
64 
65 FILE *FileSystem::Fopen(const char *path, const char *mode) {
66   return llvm::sys::RetryAfterSignal(nullptr, ::fopen, path, mode);
67 }
68 
69 int FileSystem::Open(const char *path, int flags, int mode) {
70   // Call ::open in a lambda to avoid overload resolution in RetryAfterSignal
71   // when open is overloaded, such as in Bionic.
72   auto lambda = [&]() { return ::open(path, flags, mode); };
73   return llvm::sys::RetryAfterSignal(-1, lambda);
74 }
75