init: Use std::string for write_file()
The content parameter of write_file() previously took a char* that was
then converted to a std::string in WriteStringToFd(). One unfortunate
effect of this, is that it is impossible to write data that contains
'\0' within it, as the new string will only contain characters up
until the '\0'.
This changes write_file() to take an std::string, such that
std::string::size() is used to determine the length of the string,
allowing it to contain null characters.
Also change the path parameter of read_file() and write_file() for
consistency.
Lastly, add a test for handling strings with '\0' in them.
Bug: 36726045
Bug: 36576280
Test: Boot bullhead, run unit tests
Change-Id: Idad60e4228ee2de741ab3ab6a4917065b5e63cd8
(cherry picked from commit 53089aa25ca9707e22e45e862f794bfc958d302a)
diff --git a/init/util.cpp b/init/util.cpp
index 73d97ed..c06d51b 100644
--- a/init/util.cpp
+++ b/init/util.cpp
@@ -161,10 +161,11 @@
return -1;
}
-bool read_file(const char* path, std::string* content) {
+bool read_file(const std::string& path, std::string* content) {
content->clear();
- android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(path, O_RDONLY | O_NOFOLLOW | O_CLOEXEC)));
+ android::base::unique_fd fd(
+ TEMP_FAILURE_RETRY(open(path.c_str(), O_RDONLY | O_NOFOLLOW | O_CLOEXEC)));
if (fd == -1) {
return false;
}
@@ -184,9 +185,9 @@
return android::base::ReadFdToString(fd, content);
}
-bool write_file(const char* path, const char* content) {
+bool write_file(const std::string& path, const std::string& content) {
android::base::unique_fd fd(
- TEMP_FAILURE_RETRY(open(path, O_WRONLY | O_CREAT | O_NOFOLLOW | O_CLOEXEC, 0600)));
+ TEMP_FAILURE_RETRY(open(path.c_str(), O_WRONLY | O_CREAT | O_NOFOLLOW | O_CLOEXEC, 0600)));
if (fd == -1) {
PLOG(ERROR) << "write_file: Unable to open '" << path << "'";
return false;