Move to modern utility methods from android::base.
Moves away from crufty char* operations to std::string utility
methods, including android::base methods for splitting/parsing.
Rewrite of how Process handles scanning procfs for filesystem
references; now uses fts(3) for more sane traversal.
Replace sscanf() with new FindValue() method, also has unit tests.
Remove some unused methods. Switch almost everyone over to using
modern logging library.
Test: cts-tradefed run commandAndExit cts-dev -m CtsOsTestCases -t android.os.storage.cts.StorageManagerTest
Test: cts-tradefed run commandAndExit cts-dev --abi armeabi-v7a -m CtsAppSecurityHostTestCases -t android.appsecurity.cts.AdoptableHostTest
Bug: 67041047
Change-Id: I70dc512f21459d1e25b187f24289002b2c7bc7af
diff --git a/Utils.cpp b/Utils.cpp
index a9350e8..484de90 100644
--- a/Utils.cpp
+++ b/Utils.cpp
@@ -22,6 +22,7 @@
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/properties.h>
+#include <android-base/strings.h>
#include <android-base/stringprintf.h>
#include <cutils/fs.h>
#include <logwrap/logwrap.h>
@@ -129,19 +130,19 @@
// we start sending signals
if (!VolumeManager::shutting_down) sleep(5);
- Process::killProcessesWithOpenFiles(cpath, SIGINT);
+ KillProcessesWithOpenFiles(path, SIGINT);
if (!VolumeManager::shutting_down) sleep(5);
if (!umount2(cpath, UMOUNT_NOFOLLOW) || errno == EINVAL || errno == ENOENT) {
return OK;
}
- Process::killProcessesWithOpenFiles(cpath, SIGTERM);
+ KillProcessesWithOpenFiles(path, SIGTERM);
if (!VolumeManager::shutting_down) sleep(5);
if (!umount2(cpath, UMOUNT_NOFOLLOW) || errno == EINVAL || errno == ENOENT) {
return OK;
}
- Process::killProcessesWithOpenFiles(cpath, SIGKILL);
+ KillProcessesWithOpenFiles(path, SIGKILL);
if (!VolumeManager::shutting_down) sleep(5);
if (!umount2(cpath, UMOUNT_NOFOLLOW) || errno == EINVAL || errno == ENOENT) {
return OK;
@@ -151,25 +152,24 @@
}
status_t KillProcessesUsingPath(const std::string& path) {
- const char* cpath = path.c_str();
- if (Process::killProcessesWithOpenFiles(cpath, SIGINT) == 0) {
+ if (KillProcessesWithOpenFiles(path, SIGINT) == 0) {
return OK;
}
if (!VolumeManager::shutting_down) sleep(5);
- if (Process::killProcessesWithOpenFiles(cpath, SIGTERM) == 0) {
+ if (KillProcessesWithOpenFiles(path, SIGTERM) == 0) {
return OK;
}
if (!VolumeManager::shutting_down) sleep(5);
- if (Process::killProcessesWithOpenFiles(cpath, SIGKILL) == 0) {
+ if (KillProcessesWithOpenFiles(path, SIGKILL) == 0) {
return OK;
}
if (!VolumeManager::shutting_down) sleep(5);
// Send SIGKILL a second time to determine if we've
// actually killed everyone with open files
- if (Process::killProcessesWithOpenFiles(cpath, SIGKILL) == 0) {
+ if (KillProcessesWithOpenFiles(path, SIGKILL) == 0) {
return OK;
}
PLOG(ERROR) << "Failed to kill processes using " << path;
@@ -184,11 +184,28 @@
return OK;
}
-static status_t readMetadata(const std::string& path, std::string& fsType,
- std::string& fsUuid, std::string& fsLabel, bool untrusted) {
- fsType.clear();
- fsUuid.clear();
- fsLabel.clear();
+bool FindValue(const std::string& raw, const std::string& key, std::string* value) {
+ auto qual = key + "=\"";
+ auto start = raw.find(qual);
+ if (start > 0 && raw[start - 1] != ' ') {
+ start = raw.find(qual, start + 1);
+ }
+
+ if (start == std::string::npos) return false;
+ start += qual.length();
+
+ auto end = raw.find("\"", start);
+ if (end == std::string::npos) return false;
+
+ *value = raw.substr(start, end - start);
+ return true;
+}
+
+static status_t readMetadata(const std::string& path, std::string* fsType,
+ std::string* fsUuid, std::string* fsLabel, bool untrusted) {
+ fsType->clear();
+ fsUuid->clear();
+ fsLabel->clear();
std::vector<std::string> cmd;
cmd.push_back(kBlkidPath);
@@ -209,36 +226,23 @@
return res;
}
- char value[128];
for (const auto& line : output) {
// Extract values from blkid output, if defined
- const char* cline = line.c_str();
- const char* start = strstr(cline, "TYPE=");
- if (start != nullptr && sscanf(start + 5, "\"%127[^\"]\"", value) == 1) {
- fsType = value;
- }
-
- start = strstr(cline, "UUID=");
- if (start != nullptr && sscanf(start + 5, "\"%127[^\"]\"", value) == 1) {
- fsUuid = value;
- }
-
- start = strstr(cline, "LABEL=");
- if (start != nullptr && sscanf(start + 6, "\"%127[^\"]\"", value) == 1) {
- fsLabel = value;
- }
+ FindValue(line, "TYPE", fsType);
+ FindValue(line, "UUID", fsUuid);
+ FindValue(line, "LABEL", fsLabel);
}
return OK;
}
-status_t ReadMetadata(const std::string& path, std::string& fsType,
- std::string& fsUuid, std::string& fsLabel) {
+status_t ReadMetadata(const std::string& path, std::string* fsType,
+ std::string* fsUuid, std::string* fsLabel) {
return readMetadata(path, fsType, fsUuid, fsLabel, false);
}
-status_t ReadMetadataUntrusted(const std::string& path, std::string& fsType,
- std::string& fsUuid, std::string& fsLabel) {
+status_t ReadMetadataUntrusted(const std::string& path, std::string* fsType,
+ std::string* fsUuid, std::string* fsLabel) {
return readMetadata(path, fsType, fsUuid, fsLabel, true);
}
@@ -673,15 +677,27 @@
return OK;
}
-status_t SaneReadLinkAt(int dirfd, const char* path, char* buf, size_t bufsiz) {
- ssize_t len = readlinkat(dirfd, path, buf, bufsiz);
- if (len < 0) {
- return -1;
- } else if (len == (ssize_t) bufsiz) {
- return -1;
- } else {
- buf[len] = '\0';
- return 0;
+bool Readlinkat(int dirfd, const std::string& path, std::string* result) {
+ // Shamelessly borrowed from android::base::Readlink()
+ result->clear();
+
+ // Most Linux file systems (ext2 and ext4, say) limit symbolic links to
+ // 4095 bytes. Since we'll copy out into the string anyway, it doesn't
+ // waste memory to just start there. We add 1 so that we can recognize
+ // whether it actually fit (rather than being truncated to 4095).
+ std::vector<char> buf(4095 + 1);
+ while (true) {
+ ssize_t size = readlinkat(dirfd, path.c_str(), &buf[0], buf.size());
+ // Unrecoverable error?
+ if (size == -1)
+ return false;
+ // It fit! (If size == buf.size(), it may have been truncated.)
+ if (static_cast<size_t>(size) < buf.size()) {
+ result->assign(&buf[0], size);
+ return true;
+ }
+ // Double our buffer and try again.
+ buf.resize(buf.size() * 2);
}
}