AU: Class to perform delta updates.
A class to perform delta updates and the associated unittests. Also,
change the delta diff generator executable to be able to apply a
delta, which is handy for debugging.
TEST=Attached unit test, hand-tested on real build images
BUG=552
Review URL: http://codereview.chromium.org/1718001
diff --git a/utils.cc b/utils.cc
index ff3c9db..7f05ffb 100644
--- a/utils.cc
+++ b/utils.cc
@@ -35,7 +35,7 @@
return true;
}
-bool WriteAll(int fd, const void *buf, size_t count) {
+bool WriteAll(int fd, const void* buf, size_t count) {
const char* c_buf = static_cast<const char*>(buf);
ssize_t bytes_written = 0;
while (bytes_written < static_cast<ssize_t>(count)) {
@@ -46,6 +46,36 @@
return true;
}
+bool PWriteAll(int fd, const void* buf, size_t count, off_t offset) {
+ const char* c_buf = static_cast<const char*>(buf);
+ ssize_t bytes_written = 0;
+ while (bytes_written < static_cast<ssize_t>(count)) {
+ ssize_t rc = pwrite(fd, c_buf + bytes_written, count - bytes_written,
+ offset + bytes_written);
+ TEST_AND_RETURN_FALSE_ERRNO(rc >= 0);
+ bytes_written += rc;
+ }
+ return true;
+}
+
+bool PReadAll(int fd, void* buf, size_t count, off_t offset,
+ ssize_t* out_bytes_read) {
+ char* c_buf = static_cast<char*>(buf);
+ ssize_t bytes_read = 0;
+ while (bytes_read < static_cast<ssize_t>(count)) {
+ ssize_t rc = pread(fd, c_buf + bytes_read, count - bytes_read,
+ offset + bytes_read);
+ TEST_AND_RETURN_FALSE_ERRNO(rc >= 0);
+ if (rc == 0) {
+ break;
+ }
+ bytes_read += rc;
+ }
+ *out_bytes_read = bytes_read;
+ return true;
+
+}
+
bool ReadFile(const std::string& path, std::vector<char>* out) {
CHECK(out);
FILE* fp = fopen(path.c_str(), "r");
@@ -233,6 +263,19 @@
return true;
}
+bool MakeTempDirectory(const std::string& dirname_template,
+ std::string* dirname) {
+ DCHECK(dirname);
+ vector<char> buf(dirname_template.size() + 1);
+ memcpy(&buf[0], dirname_template.data(), dirname_template.size());
+ buf[dirname_template.size()] = '\0';
+
+ char* return_code = mkdtemp(&buf[0]);
+ TEST_AND_RETURN_FALSE_ERRNO(return_code != NULL);
+ *dirname = &buf[0];
+ return true;
+}
+
bool StringHasSuffix(const std::string& str, const std::string& suffix) {
if (suffix.size() > str.size())
return false;
@@ -273,8 +316,9 @@
}
bool MountFilesystem(const string& device,
- const string& mountpoint) {
- int rc = mount(device.c_str(), mountpoint.c_str(), "ext3", 0, NULL);
+ const string& mountpoint,
+ unsigned long mountflags) {
+ int rc = mount(device.c_str(), mountpoint.c_str(), "ext3", mountflags, NULL);
if (rc < 0) {
string msg = ErrnoNumberAsString(errno);
LOG(ERROR) << "Unable to mount destination device: " << msg << ". "
