1 //===-- sanitizer_file.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 // This file is shared between AddressSanitizer and ThreadSanitizer
10 // run-time libraries. It defines filesystem-related interfaces. This
11 // is separate from sanitizer_common.cpp so that it's simpler to disable
12 // all the filesystem support code for a port that doesn't use it.
13 //
14 //===---------------------------------------------------------------------===//
15
16 #include "sanitizer_platform.h"
17
18 #if !SANITIZER_FUCHSIA
19
20 #include "sanitizer_common.h"
21 #include "sanitizer_file.h"
22
23 namespace __sanitizer {
24
CatastrophicErrorWrite(const char * buffer,uptr length)25 void CatastrophicErrorWrite(const char *buffer, uptr length) {
26 WriteToFile(kStderrFd, buffer, length);
27 }
28
29 StaticSpinMutex report_file_mu;
30 ReportFile report_file = {&report_file_mu, kStderrFd, "", "", 0};
31
RawWrite(const char * buffer)32 void RawWrite(const char *buffer) {
33 report_file.Write(buffer, internal_strlen(buffer));
34 }
35
ReopenIfNecessary()36 void ReportFile::ReopenIfNecessary() {
37 mu->CheckLocked();
38 if (fd == kStdoutFd || fd == kStderrFd) return;
39
40 uptr pid = internal_getpid();
41 // If in tracer, use the parent's file.
42 if (pid == stoptheworld_tracer_pid)
43 pid = stoptheworld_tracer_ppid;
44 if (fd != kInvalidFd) {
45 // If the report file is already opened by the current process,
46 // do nothing. Otherwise the report file was opened by the parent
47 // process, close it now.
48 if (fd_pid == pid)
49 return;
50 else
51 CloseFile(fd);
52 }
53
54 const char *exe_name = GetProcessName();
55 if (common_flags()->log_exe_name && exe_name) {
56 internal_snprintf(full_path, kMaxPathLength, "%s.%s.%zu", path_prefix,
57 exe_name, pid);
58 } else {
59 internal_snprintf(full_path, kMaxPathLength, "%s.%zu", path_prefix, pid);
60 }
61 error_t err;
62 fd = OpenFile(full_path, WrOnly, &err);
63 if (fd == kInvalidFd) {
64 const char *ErrorMsgPrefix = "ERROR: Can't open file: ";
65 WriteToFile(kStderrFd, ErrorMsgPrefix, internal_strlen(ErrorMsgPrefix));
66 WriteToFile(kStderrFd, full_path, internal_strlen(full_path));
67 char errmsg[100];
68 internal_snprintf(errmsg, sizeof(errmsg), " (reason: %d)", err);
69 WriteToFile(kStderrFd, errmsg, internal_strlen(errmsg));
70 Die();
71 }
72 fd_pid = pid;
73 }
74
SetReportPath(const char * path)75 void ReportFile::SetReportPath(const char *path) {
76 if (path) {
77 uptr len = internal_strlen(path);
78 if (len > sizeof(path_prefix) - 100) {
79 Report("ERROR: Path is too long: %c%c%c%c%c%c%c%c...\n", path[0], path[1],
80 path[2], path[3], path[4], path[5], path[6], path[7]);
81 Die();
82 }
83 }
84
85 SpinMutexLock l(mu);
86 if (fd != kStdoutFd && fd != kStderrFd && fd != kInvalidFd)
87 CloseFile(fd);
88 fd = kInvalidFd;
89 if (!path || internal_strcmp(path, "stderr") == 0) {
90 fd = kStderrFd;
91 } else if (internal_strcmp(path, "stdout") == 0) {
92 fd = kStdoutFd;
93 } else {
94 internal_snprintf(path_prefix, kMaxPathLength, "%s", path);
95 }
96 }
97
GetReportPath()98 const char *ReportFile::GetReportPath() {
99 SpinMutexLock l(mu);
100 ReopenIfNecessary();
101 return full_path;
102 }
103
ReadFileToBuffer(const char * file_name,char ** buff,uptr * buff_size,uptr * read_len,uptr max_len,error_t * errno_p)104 bool ReadFileToBuffer(const char *file_name, char **buff, uptr *buff_size,
105 uptr *read_len, uptr max_len, error_t *errno_p) {
106 *buff = nullptr;
107 *buff_size = 0;
108 *read_len = 0;
109 if (!max_len)
110 return true;
111 uptr PageSize = GetPageSizeCached();
112 uptr kMinFileLen = Min(PageSize, max_len);
113
114 // The files we usually open are not seekable, so try different buffer sizes.
115 for (uptr size = kMinFileLen;; size = Min(size * 2, max_len)) {
116 UnmapOrDie(*buff, *buff_size);
117 *buff = (char*)MmapOrDie(size, __func__);
118 *buff_size = size;
119 fd_t fd = OpenFile(file_name, RdOnly, errno_p);
120 if (fd == kInvalidFd) {
121 UnmapOrDie(*buff, *buff_size);
122 return false;
123 }
124 *read_len = 0;
125 // Read up to one page at a time.
126 bool reached_eof = false;
127 while (*read_len < size) {
128 uptr just_read;
129 if (!ReadFromFile(fd, *buff + *read_len, size - *read_len, &just_read,
130 errno_p)) {
131 UnmapOrDie(*buff, *buff_size);
132 CloseFile(fd);
133 return false;
134 }
135 *read_len += just_read;
136 if (just_read == 0 || *read_len == max_len) {
137 reached_eof = true;
138 break;
139 }
140 }
141 CloseFile(fd);
142 if (reached_eof) // We've read the whole file.
143 break;
144 }
145 return true;
146 }
147
ReadFileToVector(const char * file_name,InternalMmapVectorNoCtor<char> * buff,uptr max_len,error_t * errno_p)148 bool ReadFileToVector(const char *file_name,
149 InternalMmapVectorNoCtor<char> *buff, uptr max_len,
150 error_t *errno_p) {
151 buff->clear();
152 if (!max_len)
153 return true;
154 uptr PageSize = GetPageSizeCached();
155 fd_t fd = OpenFile(file_name, RdOnly, errno_p);
156 if (fd == kInvalidFd)
157 return false;
158 uptr read_len = 0;
159 while (read_len < max_len) {
160 if (read_len >= buff->size())
161 buff->resize(Min(Max(PageSize, read_len * 2), max_len));
162 CHECK_LT(read_len, buff->size());
163 CHECK_LE(buff->size(), max_len);
164 uptr just_read;
165 if (!ReadFromFile(fd, buff->data() + read_len, buff->size() - read_len,
166 &just_read, errno_p)) {
167 CloseFile(fd);
168 return false;
169 }
170 read_len += just_read;
171 if (!just_read)
172 break;
173 }
174 CloseFile(fd);
175 buff->resize(read_len);
176 return true;
177 }
178
179 static const char kPathSeparator = SANITIZER_WINDOWS ? ';' : ':';
180
FindPathToBinary(const char * name)181 char *FindPathToBinary(const char *name) {
182 if (FileExists(name)) {
183 return internal_strdup(name);
184 }
185
186 const char *path = GetEnv("PATH");
187 if (!path)
188 return nullptr;
189 uptr name_len = internal_strlen(name);
190 InternalMmapVector<char> buffer(kMaxPathLength);
191 const char *beg = path;
192 while (true) {
193 const char *end = internal_strchrnul(beg, kPathSeparator);
194 uptr prefix_len = end - beg;
195 if (prefix_len + name_len + 2 <= kMaxPathLength) {
196 internal_memcpy(buffer.data(), beg, prefix_len);
197 buffer[prefix_len] = '/';
198 internal_memcpy(&buffer[prefix_len + 1], name, name_len);
199 buffer[prefix_len + 1 + name_len] = '\0';
200 if (FileExists(buffer.data()))
201 return internal_strdup(buffer.data());
202 }
203 if (*end == '\0') break;
204 beg = end + 1;
205 }
206 return nullptr;
207 }
208
209 } // namespace __sanitizer
210
211 using namespace __sanitizer;
212
213 extern "C" {
__sanitizer_set_report_path(const char * path)214 void __sanitizer_set_report_path(const char *path) {
215 report_file.SetReportPath(path);
216 }
217
__sanitizer_set_report_fd(void * fd)218 void __sanitizer_set_report_fd(void *fd) {
219 report_file.fd = (fd_t)reinterpret_cast<uptr>(fd);
220 report_file.fd_pid = internal_getpid();
221 }
222
__sanitizer_get_report_path()223 const char *__sanitizer_get_report_path() {
224 return report_file.GetReportPath();
225 }
226 } // extern "C"
227
228 #endif // !SANITIZER_FUCHSIA
229