recovery: install packages in a known mount environment

When installing a package, we should have /tmp and /cache mounted and
nothing else.  Ensure this is true by explicitly mounting them and
unmounting everything else as the first step of every install.

Also fix an error in the progress bar that crops up when you do
multiple package installs in one instance of recovery.

Change-Id: I4837ed707cb419ddd3d9f6188b6355ba1bcfe2b2

install.cpp

@@ -180,7 +180,9 @@ really_install_package(const char *path, int* wipe_cache)
 {
     ui->SetBackground(RecoveryUI::INSTALLING_UPDATE);
     ui->Print("Finding update package...\n");
-    ui->SetProgressType(RecoveryUI::INDETERMINATE);
+    // Give verification half the progress bar...
+    ui->SetProgressType(RecoveryUI::DETERMINATE);
+    ui->ShowProgress(VERIFICATION_PROGRESS_FRACTION, VERIFICATION_PROGRESS_TIME);
     LOGI("Update location: %s\n", path);
 
     if (ensure_path_mounted(path) != 0) {
@@ -198,10 +200,7 @@ really_install_package(const char *path, int* wipe_cache)
     }
     LOGI("%d key(s) loaded from %s\n", numKeys, PUBLIC_KEYS_FILE);
 
-    // Give verification half the progress bar...
     ui->Print("Verifying update package...\n");
-    ui->SetProgressType(RecoveryUI::DETERMINATE);
-    ui->ShowProgress(VERIFICATION_PROGRESS_FRACTION, VERIFICATION_PROGRESS_TIME);
 
     int err;
     err = verify_file(path, loadedKeys, numKeys);
@@ -237,7 +236,13 @@ install_package(const char* path, int* wipe_cache, const char* install_file)
     } else {
         LOGE("failed to open last_install: %s\n", strerror(errno));
     }
-    int result = really_install_package(path, wipe_cache);
+    int result;
+    if (setup_install_mounts() != 0) {
+        LOGE("failed to set up expected mounts for install; aborting\n");
+        result = INSTALL_ERROR;
+    } else {
+        result = really_install_package(path, wipe_cache);
+    }
     if (install_log) {
         fputc(result == INSTALL_SUCCESS ? '1' : '0', install_log);
         fputc('\n', install_log);

recovery.cpp

@@ -811,10 +811,6 @@ prompt_and_wait(Device* device, int status) {
                 break;
 
             case Device::APPLY_EXT:
-                // Some packages expect /cache to be mounted (eg,
-                // standard incremental packages expect to use /cache
-                // as scratch space).
-                ensure_path_mounted(CACHE_ROOT);
                 status = update_directory(SDCARD_ROOT, SDCARD_ROOT, &wipe_cache, device);
                 if (status == INSTALL_SUCCESS && wipe_cache) {
                     ui->Print("\n-- Wiping cache (at package request)...\n");
@@ -860,7 +856,6 @@ prompt_and_wait(Device* device, int status) {
                 break;
 
             case Device::APPLY_ADB_SIDELOAD:
-                ensure_path_mounted(CACHE_ROOT);
                 status = apply_from_adb(ui, &wipe_cache, TEMPORARY_INSTALL_FILE);
                 if (status >= 0) {
                     if (status != INSTALL_SUCCESS) {

roots.cpp

@@ -202,3 +202,22 @@ int format_volume(const char* volume) {
     LOGE("format_volume: fs_type \"%s\" unsupported\n", v->fs_type);
     return -1;
 }
+
+int setup_install_mounts() {
+    if (fstab == NULL) {
+        LOGE("can't set up install mounts: no fstab loaded\n");
+        return -1;
+    }
+    for (int i = 0; i < fstab->num_entries; ++i) {
+        Volume* v = fstab->recs + i;
+
+        if (strcmp(v->mount_point, "/tmp") == 0 ||
+            strcmp(v->mount_point, "/cache") == 0) {
+            if (ensure_path_mounted(v->mount_point) != 0) return -1;
+
+        } else {
+            if (ensure_path_unmounted(v->mount_point) != 0) return -1;
+        }
+    }
+    return 0;
+}

roots.h

@@ -42,6 +42,10 @@ int ensure_path_unmounted(const char* path);
 // it is mounted.
 int format_volume(const char* volume);
 
+// Ensure that all and only the volumes that packages expect to find
+// mounted (/tmp and /cache) are mounted.  Returns 0 on success.
+int setup_install_mounts();
+
 #ifdef __cplusplus
 }
 #endif

screen_ui.cpp

@@ -467,10 +467,11 @@ void ScreenRecoveryUI::SetProgressType(ProgressType type)
     pthread_mutex_lock(&updateMutex);
     if (progressBarType != type) {
         progressBarType = type;
-        update_progress_locked();
     }
     progressScopeStart = 0;
+    progressScopeSize = 0;
     progress = 0;
+    update_progress_locked();
     pthread_mutex_unlock(&updateMutex);
 }