close update package before installing; allow remount

Close the update package before invoking the binary, to allow the
installer to unmount /cache if it wants to.  Add a function to allow
remounting of a mount as read-only.

Change-Id: Idfcc96c3da66083295177f729263560be58034e4

install.c

@@ -42,6 +42,7 @@ try_update_binary(const char *path, ZipArchive *zip) {
     const ZipEntry* binary_entry =
             mzFindZipEntry(zip, ASSUMED_UPDATE_BINARY_NAME);
     if (binary_entry == NULL) {
+        mzCloseZipArchive(zip);
         return INSTALL_CORRUPT;
     }
 
@@ -49,11 +50,13 @@ try_update_binary(const char *path, ZipArchive *zip) {
     unlink(binary);
     int fd = creat(binary, 0755);
     if (fd < 0) {
+        mzCloseZipArchive(zip);
         LOGE("Can't make %s\n", binary);
         return 1;
     }
     bool ok = mzExtractZipEntryToFile(zip, binary_entry, fd);
     close(fd);
+    mzCloseZipArchive(zip);
 
     if (!ok) {
         LOGE("Can't copy %s\n", ASSUMED_UPDATE_BINARY_NAME);
@@ -298,6 +301,5 @@ install_package(const char *root_path)
     /* Verify and install the contents of the package.
      */
     int status = handle_update_package(path, &zip);
-    mzCloseZipArchive(&zip);
     return status;
 }

mtdutils/mounts.c

@@ -212,3 +212,11 @@ unmount_mounted_volume(const MountedVolume *volume)
     }
     return ret;
 }
+
+int
+remount_read_only(const MountedVolume* volume)
+{
+    return mount(volume->device, volume->mount_point, volume->filesystem,
+                 MS_NOATIME | MS_NODEV | MS_NODIRATIME |
+                 MS_RDONLY | MS_REMOUNT, 0);
+}

mtdutils/mounts.h

@@ -28,4 +28,6 @@ find_mounted_volume_by_mount_point(const char *mount_point);
 
 int unmount_mounted_volume(const MountedVolume *volume);
 
+int remount_read_only(const MountedVolume* volume);
+
 #endif  // MTDUTILS_MOUNTS_H_

mtdutils/mtdutils.c

@@ -455,7 +455,7 @@ static int write_block(MtdWriteContext *ctx, const char *data)
             if (retry > 0) {
                 fprintf(stderr, "mtd: wrote block after %d retries\n", retry);
             }
-            fprintf(stderr, "mtd: successfully wrote block at %x\n", pos);
+            fprintf(stderr, "mtd: successfully wrote block at %llx\n", pos);
             return 0;  // Success!
         }
 

updater/updater.c

@@ -136,7 +136,9 @@ int main(int argc, char** argv) {
         free(result);
     }
 
-    mzCloseZipArchive(&za);
+    if (updater_info.package_zip) {
+        mzCloseZipArchive(updater_info.package_zip);
+    }
     free(script);
 
     return 0;