1//===- FuzzerIO.cpp - IO utils. -------------------------------------------===//
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// IO functions.
9//===----------------------------------------------------------------------===//
10
11#include "FuzzerDefs.h"
12#include "FuzzerExtFunctions.h"
13#include "FuzzerIO.h"
14#include "FuzzerUtil.h"
15#include <algorithm>
16#include <cstdarg>
17#include <fstream>
18#include <iterator>
19#include <sys/stat.h>
20#include <sys/types.h>
21
22namespace fuzzer {
23
24static FILE *OutputFile = stderr;
25
26FILE *GetOutputFile() {
27 return OutputFile;
28}
29
30void SetOutputFile(FILE *NewOutputFile) {
31 OutputFile = NewOutputFile;
32}
33
34long GetEpoch(const std::string &Path) {
35 struct stat St;
36 if (stat(file: Path.c_str(), buf: &St))
37 return 0; // Can't stat, be conservative.
38 return St.st_mtime;
39}
40
41Unit FileToVector(const std::string &Path, size_t MaxSize, bool ExitOnError) {
42 std::ifstream T(Path, std::ios::binary);
43 if (ExitOnError && !T) {
44 Printf(Fmt: "No such directory: %s; exiting\n", Path.c_str());
45 exit(status: 1);
46 }
47
48 T.seekg(off: 0, dir: T.end);
49 auto EndPos = T.tellg();
50 if (EndPos < 0) return {};
51 size_t FileLen = EndPos;
52 if (MaxSize)
53 FileLen = std::min(a: FileLen, b: MaxSize);
54
55 T.seekg(off: 0, dir: T.beg);
56 Unit Res(FileLen);
57 T.read(s: reinterpret_cast<char *>(Res.data()), n: FileLen);
58 return Res;
59}
60
61std::string FileToString(const std::string &Path) {
62 std::ifstream T(Path, std::ios::binary);
63 return std::string((std::istreambuf_iterator<char>(T)),
64 std::istreambuf_iterator<char>());
65}
66
67void CopyFileToErr(const std::string &Path) {
68 Puts(Str: FileToString(Path).c_str());
69}
70
71void WriteToFile(const Unit &U, const std::string &Path) {
72 WriteToFile(Data: U.data(), Size: U.size(), Path);
73}
74
75void WriteToFile(const std::string &Data, const std::string &Path) {
76 WriteToFile(Data: reinterpret_cast<const uint8_t *>(Data.c_str()), Size: Data.size(),
77 Path);
78}
79
80void WriteToFile(const uint8_t *Data, size_t Size, const std::string &Path) {
81 // Use raw C interface because this function may be called from a sig handler.
82 FILE *Out = fopen(filename: Path.c_str(), modes: "wb");
83 if (!Out) return;
84 fwrite(ptr: Data, size: sizeof(Data[0]), n: Size, s: Out);
85 fclose(stream: Out);
86}
87
88void AppendToFile(const std::string &Data, const std::string &Path) {
89 AppendToFile(Data: reinterpret_cast<const uint8_t *>(Data.data()), Size: Data.size(),
90 Path);
91}
92
93void AppendToFile(const uint8_t *Data, size_t Size, const std::string &Path) {
94 FILE *Out = fopen(filename: Path.c_str(), modes: "a");
95 if (!Out)
96 return;
97 fwrite(ptr: Data, size: sizeof(Data[0]), n: Size, s: Out);
98 fclose(stream: Out);
99}
100
101void ReadDirToVectorOfUnits(const char *Path, std::vector<Unit> *V, long *Epoch,
102 size_t MaxSize, bool ExitOnError,
103 std::vector<std::string> *VPaths) {
104 long E = Epoch ? *Epoch : 0;
105 std::vector<std::string> Files;
106 ListFilesInDirRecursive(Dir: Path, Epoch, V: &Files, /*TopDir*/true);
107 size_t NumLoaded = 0;
108 for (size_t i = 0; i < Files.size(); i++) {
109 auto &X = Files[i];
110 if (Epoch && GetEpoch(Path: X) < E) continue;
111 NumLoaded++;
112 if ((NumLoaded & (NumLoaded - 1)) == 0 && NumLoaded >= 1024)
113 Printf(Fmt: "Loaded %zd/%zd files from %s\n", NumLoaded, Files.size(), Path);
114 auto S = FileToVector(Path: X, MaxSize, ExitOnError);
115 if (!S.empty()) {
116 V->push_back(x: S);
117 if (VPaths)
118 VPaths->push_back(x: X);
119 }
120 }
121}
122
123void GetSizedFilesFromDir(const std::string &Dir, std::vector<SizedFile> *V) {
124 std::vector<std::string> Files;
125 ListFilesInDirRecursive(Dir, Epoch: 0, V: &Files, /*TopDir*/true);
126 for (auto &File : Files)
127 if (size_t Size = FileSize(Path: File))
128 V->push_back(x: {.File: File, .Size: Size});
129}
130
131std::string DirPlusFile(const std::string &DirPath,
132 const std::string &FileName) {
133 return DirPath + GetSeparator() + FileName;
134}
135
136void DupAndCloseStderr() {
137 int OutputFd = DuplicateFile(Fd: 2);
138 if (OutputFd >= 0) {
139 FILE *NewOutputFile = OpenFile(Fd: OutputFd, Mode: "w");
140 if (NewOutputFile) {
141 OutputFile = NewOutputFile;
142 if (EF->__sanitizer_set_report_fd)
143 EF->__sanitizer_set_report_fd(
144 reinterpret_cast<void *>(GetHandleFromFd(fd: OutputFd)));
145 DiscardOutput(Fd: 2);
146 }
147 }
148}
149
150void CloseStdout() {
151 DiscardOutput(Fd: 1);
152}
153
154void Puts(const char *Str) {
155 fputs(s: Str, stream: OutputFile);
156 fflush(stream: OutputFile);
157}
158
159void Printf(const char *Fmt, ...) {
160 va_list ap;
161 va_start(ap, Fmt);
162 vfprintf(s: OutputFile, format: Fmt, arg: ap);
163 va_end(ap);
164 fflush(stream: OutputFile);
165}
166
167void VPrintf(bool Verbose, const char *Fmt, ...) {
168 if (!Verbose) return;
169 va_list ap;
170 va_start(ap, Fmt);
171 vfprintf(s: OutputFile, format: Fmt, arg: ap);
172 va_end(ap);
173 fflush(stream: OutputFile);
174}
175
176static bool MkDirRecursiveInner(const std::string &Leaf) {
177 // Prevent chance of potential infinite recursion
178 if (Leaf == ".")
179 return true;
180
181 const std::string &Dir = DirName(FileName: Leaf);
182
183 if (IsDirectory(Path: Dir)) {
184 MkDir(Path: Leaf);
185 return IsDirectory(Path: Leaf);
186 }
187
188 bool ret = MkDirRecursiveInner(Leaf: Dir);
189 if (!ret) {
190 // Give up early if a previous MkDir failed
191 return ret;
192 }
193
194 MkDir(Path: Leaf);
195 return IsDirectory(Path: Leaf);
196}
197
198bool MkDirRecursive(const std::string &Dir) {
199 if (Dir.empty())
200 return false;
201
202 if (IsDirectory(Path: Dir))
203 return true;
204
205 return MkDirRecursiveInner(Leaf: Dir);
206}
207
208void RmDirRecursive(const std::string &Dir) {
209 IterateDirRecursive(
210 Dir, DirPreCallback: [](const std::string &Path) {},
211 DirPostCallback: [](const std::string &Path) { RmDir(Path); },
212 FileCallback: [](const std::string &Path) { RemoveFile(Path); });
213}
214
215std::string TempPath(const char *Prefix, const char *Extension) {
216 return DirPlusFile(DirPath: TmpDir(), FileName: std::string("libFuzzerTemp.") + Prefix +
217 std::to_string(val: GetPid()) + Extension);
218}
219
220} // namespace fuzzer
221