AU: Delta Diff Generator
Adds a class that can take two root filesystem image and generate a
delta between them. Currently it's not very well tested, but this will
improve once the diff applicator is written.
Also, an executable to run the generator.
Other changes:
- Stop leaking loop devices in unittests
- extent mapper: support sparse files, ability to get FS block size
- AppendBlockToExtents support sparse files
- subprocess more verbose on errors
- add WriteAll to utils (WriteAll avoids short-write() returns)
- mkstemp wrapper for ease of use
- VectorIndexOf, finds index of an element in a vector
Review URL: http://codereview.chromium.org/891002
diff --git a/utils.cc b/utils.cc
index 69a59cc..e1ed874 100644
--- a/utils.cc
+++ b/utils.cc
@@ -35,6 +35,17 @@
return true;
}
+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)) {
+ ssize_t rc = write(fd, c_buf + bytes_written, count - bytes_written);
+ TEST_AND_RETURN_FALSE_ERRNO(rc >= 0);
+ bytes_written += rc;
+ }
+ return true;
+}
+
bool ReadFile(const std::string& path, std::vector<char>* out) {
CHECK(out);
FILE* fp = fopen(path.c_str(), "r");
@@ -114,7 +125,7 @@
return true;
if (!S_ISDIR(stbuf.st_mode)) {
TEST_AND_RETURN_FALSE_ERRNO((unlink(path.c_str()) == 0) ||
- (errno == ENOENT));
+ (errno == ENOENT));
// success or path disappeared before we could unlink.
return true;
}
@@ -136,7 +147,7 @@
!strcmp(dir_entry_p->d_name, ".."))
continue;
TEST_AND_RETURN_FALSE(RecursiveUnlinkDir(path + "/" +
- dir_entry_p->d_name));
+ dir_entry_p->d_name));
}
TEST_AND_RETURN_FALSE(err == 0);
}
@@ -201,6 +212,27 @@
return path;
}
+bool MakeTempFile(const std::string& filename_template,
+ std::string* filename,
+ int* fd) {
+ DCHECK(filename || fd);
+ vector<char> buf(filename_template.size() + 1);
+ memcpy(&buf[0], filename_template.data(), filename_template.size());
+ buf[filename_template.size()] = '\0';
+
+ int mkstemp_fd = mkstemp(&buf[0]);
+ TEST_AND_RETURN_FALSE_ERRNO(mkstemp_fd >= 0);
+ if (filename) {
+ *filename = &buf[0];
+ }
+ if (fd) {
+ *fd = mkstemp_fd;
+ } else {
+ close(mkstemp_fd);
+ }
+ return true;
+}
+
bool StringHasSuffix(const std::string& str, const std::string& suffix) {
if (suffix.size() > str.size())
return false;