1 //===-- FileCache.cpp -------------------------------------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "lldb/Host/FileCache.h"
11
12 #include "lldb/Host/File.h"
13 #include "lldb/Host/FileSystem.h"
14
15 using namespace lldb;
16 using namespace lldb_private;
17
18 FileCache *FileCache::m_instance = nullptr;
19
GetInstance()20 FileCache &FileCache::GetInstance() {
21 if (m_instance == nullptr)
22 m_instance = new FileCache();
23
24 return *m_instance;
25 }
26
OpenFile(const FileSpec & file_spec,uint32_t flags,uint32_t mode,Status & error)27 lldb::user_id_t FileCache::OpenFile(const FileSpec &file_spec, uint32_t flags,
28 uint32_t mode, Status &error) {
29 if (!file_spec) {
30 error.SetErrorString("empty path");
31 return UINT64_MAX;
32 }
33 FileSP file_sp(new File());
34 error = FileSystem::Instance().Open(*file_sp, file_spec, flags, mode);
35 if (!file_sp->IsValid())
36 return UINT64_MAX;
37 lldb::user_id_t fd = file_sp->GetDescriptor();
38 m_cache[fd] = file_sp;
39 return fd;
40 }
41
CloseFile(lldb::user_id_t fd,Status & error)42 bool FileCache::CloseFile(lldb::user_id_t fd, Status &error) {
43 if (fd == UINT64_MAX) {
44 error.SetErrorString("invalid file descriptor");
45 return false;
46 }
47 FDToFileMap::iterator pos = m_cache.find(fd);
48 if (pos == m_cache.end()) {
49 error.SetErrorStringWithFormat("invalid host file descriptor %" PRIu64, fd);
50 return false;
51 }
52 FileSP file_sp = pos->second;
53 if (!file_sp) {
54 error.SetErrorString("invalid host backing file");
55 return false;
56 }
57 error = file_sp->Close();
58 m_cache.erase(pos);
59 return error.Success();
60 }
61
WriteFile(lldb::user_id_t fd,uint64_t offset,const void * src,uint64_t src_len,Status & error)62 uint64_t FileCache::WriteFile(lldb::user_id_t fd, uint64_t offset,
63 const void *src, uint64_t src_len,
64 Status &error) {
65 if (fd == UINT64_MAX) {
66 error.SetErrorString("invalid file descriptor");
67 return UINT64_MAX;
68 }
69 FDToFileMap::iterator pos = m_cache.find(fd);
70 if (pos == m_cache.end()) {
71 error.SetErrorStringWithFormat("invalid host file descriptor %" PRIu64, fd);
72 return false;
73 }
74 FileSP file_sp = pos->second;
75 if (!file_sp) {
76 error.SetErrorString("invalid host backing file");
77 return UINT64_MAX;
78 }
79 if (static_cast<uint64_t>(file_sp->SeekFromStart(offset, &error)) != offset ||
80 error.Fail())
81 return UINT64_MAX;
82 size_t bytes_written = src_len;
83 error = file_sp->Write(src, bytes_written);
84 if (error.Fail())
85 return UINT64_MAX;
86 return bytes_written;
87 }
88
ReadFile(lldb::user_id_t fd,uint64_t offset,void * dst,uint64_t dst_len,Status & error)89 uint64_t FileCache::ReadFile(lldb::user_id_t fd, uint64_t offset, void *dst,
90 uint64_t dst_len, Status &error) {
91 if (fd == UINT64_MAX) {
92 error.SetErrorString("invalid file descriptor");
93 return UINT64_MAX;
94 }
95 FDToFileMap::iterator pos = m_cache.find(fd);
96 if (pos == m_cache.end()) {
97 error.SetErrorStringWithFormat("invalid host file descriptor %" PRIu64, fd);
98 return false;
99 }
100 FileSP file_sp = pos->second;
101 if (!file_sp) {
102 error.SetErrorString("invalid host backing file");
103 return UINT64_MAX;
104 }
105 if (static_cast<uint64_t>(file_sp->SeekFromStart(offset, &error)) != offset ||
106 error.Fail())
107 return UINT64_MAX;
108 size_t bytes_read = dst_len;
109 error = file_sp->Read(dst, bytes_read);
110 if (error.Fail())
111 return UINT64_MAX;
112 return bytes_read;
113 }
114