update_engine: Add MtdFileDescriptor and UbiFileDescriptor
We send a pure file descriptor to ExtentWriter. This CL changes that to
use FileDescriptor. At the same time, the CL adds two other
FileDescriptor classes MtdFileDescriptor and UbiFileDescriptor to work
with raw NAND and UBI devices. Both of these classes support either read
only or sequential write, but not both at the same time. Seek operation
is possible in read only mode.
These classes are conditionally included if USE_mtd is not '0'.
BUG=chromium:426742
TEST=unittest
TEST=USE=mtd emerge update_engine, make sure there is MtdFileDescriptor
in /usr/sbin/update_engine
TEST=emerge --unmerge android_mtdutils; USE=-mtd emerge update_engine
make sure there is no UbiFileDescriptor in that same file
Change-Id: If3ba43677d93dc4f3cea037f19866c8b546b2cae
Reviewed-on: https://chromium-review.googlesource.com/229004
Reviewed-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Alex Deymo <deymo@chromium.org>
Commit-Queue: Nam Nguyen <namnguyen@chromium.org>
Tested-by: Nam Nguyen <namnguyen@chromium.org>
diff --git a/utils.cc b/utils.cc
index b84eda0..9a596a7 100644
--- a/utils.cc
+++ b/utils.cc
@@ -40,6 +40,7 @@
#include "update_engine/clock_interface.h"
#include "update_engine/constants.h"
+#include "update_engine/file_descriptor.h"
#include "update_engine/file_writer.h"
#include "update_engine/omaha_request_params.h"
#include "update_engine/prefs_interface.h"
@@ -162,6 +163,25 @@
return true;
}
+bool WriteAll(FileDescriptorPtr 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)) {
+ ssize_t rc = fd->Write(c_buf + bytes_written, count - bytes_written);
+ TEST_AND_RETURN_FALSE_ERRNO(rc >= 0);
+ bytes_written += rc;
+ }
+ return true;
+}
+
+bool PWriteAll(FileDescriptorPtr fd,
+ const void* buf,
+ size_t count,
+ off_t offset) {
+ TEST_AND_RETURN_FALSE_ERRNO(fd->Seek(offset, SEEK_SET));
+ return WriteAll(fd, buf, count);
+}
+
bool PReadAll(int fd, void* buf, size_t count, off_t offset,
ssize_t* out_bytes_read) {
char* c_buf = static_cast<char*>(buf);
@@ -179,6 +199,23 @@
return true;
}
+bool PReadAll(FileDescriptorPtr fd, void* buf, size_t count, off_t offset,
+ ssize_t* out_bytes_read) {
+ TEST_AND_RETURN_FALSE_ERRNO(fd->Seek(offset, SEEK_SET));
+ char* c_buf = static_cast<char*>(buf);
+ ssize_t bytes_read = 0;
+ while (bytes_read < static_cast<ssize_t>(count)) {
+ ssize_t rc = fd->Read(c_buf + bytes_read, count - bytes_read);
+ TEST_AND_RETURN_FALSE_ERRNO(rc >= 0);
+ if (rc == 0) {
+ break;
+ }
+ bytes_read += rc;
+ }
+ *out_bytes_read = bytes_read;
+ return true;
+}
+
// Append |nbytes| of content from |buf| to the vector pointed to by either
// |vec_p| or |str_p|.
static void AppendBytes(const char* buf, size_t nbytes,