Improve progress bar handling for backup / restore / image flash

The progress bar will now be updated during image backups, restores
and during image flashing (except for sparse images which will require
significant changes to libsparse, and except for mtd nand using
flash_utils).

The progress bar will now be updated mid-file for file systems (tar) so
the user will see changes even during large file backup / restore.

Add a new progress tracking class to simplify handling of progress bar
updates. The class will only update the progress bar 5 times a second to
reduce the CPU load from updating the GUI frequently which does affect
backup times.

Change-Id: Iff382faef3df1f86604af336c1a8ce8993cd12c5

Android.mk

@@ -54,6 +54,7 @@ LOCAL_SRC_FILES += \
     data.cpp \
     partition.cpp \
     partitionmanager.cpp \
+    progresstracking.cpp \
     twinstall.cpp \
     twrp-functions.cpp \
     openrecoveryscript.cpp \

gui/twmsg.cpp

@@ -89,13 +89,16 @@ class ResourceLookup : public StringLookup
 			resname = name.substr(0, pos);
 			default_value = name.substr(pos + 1);
 		}
+#ifndef BUILD_TWRPTAR_MAIN
 		const ResourceManager* res = PageManager::GetResources();
 		if (res) {
 			if (default_value.empty())
 				return res->FindString(resname);
 			else
 				return res->FindString(resname, default_value);
-		} else if (!default_value.empty()) {
+		}
+#endif
+		if (!default_value.empty()) {
 			return default_value;
 		}
 		return name;
@@ -112,10 +115,12 @@ class DataLookup : public StringLookup
 public:
 	virtual std::string operator()(const std::string& name) const
 	{
+#ifndef BUILD_TWRPTAR_MAIN
 		std::string value;
 		if (DataManager::GetValue(name, value) == 0)
 			return value;
 		else
+#endif
 			return "";
 	}
 };

libtar/extract.c

@@ -32,6 +32,8 @@
 # include "selinux/selinux.h"
 #endif
 
+const unsigned long long progress_size = (unsigned long long)(T_BLOCKSIZE);
+
 static int
 tar_set_file_perms(TAR *t, const char *realname)
 {
@@ -245,6 +247,11 @@ tar_extract_regfile(TAR *t, const char *realname, const int *progress_fd)
 			close(fdout);
 			return -1;
 		}
+		else
+		{
+			if (*progress_fd != 0)
+				write(*progress_fd, &progress_size, sizeof(progress_size));
+		}
 	}
 
 	/* close output file */
@@ -255,12 +262,6 @@ tar_extract_regfile(TAR *t, const char *realname, const int *progress_fd)
 	printf("### done extracting %s\n", filename);
 #endif
 
-	if (*progress_fd != 0)
-	{
-		unsigned long long file_size = (unsigned long long)(size);
-		write(*progress_fd, &file_size, sizeof(file_size));
-	}
-
 	return 0;
 }