recovery: preserve recovery logs across cache wipes
When doing a cache wipe or a factory reset (which includes a cache
wipe), save any last* log files in the /cache/recovery directory and
write them back after reformatting the partition, so that wiping data
doesn't lose useful log information.
Change-Id: I1f52ae9131760b5e752e136645c19f71b7b166ee
diff --git a/recovery.cpp b/recovery.cpp
index b7fb616..82cfc3f 100644
--- a/recovery.cpp
+++ b/recovery.cpp
@@ -61,6 +61,7 @@
#define LAST_LOG_FILE "/cache/recovery/last_log"
+static const char *CACHE_LOG_DIR = "/cache/recovery";
static const char *COMMAND_FILE = "/cache/recovery/command";
static const char *INTENT_FILE = "/cache/recovery/intent";
static const char *LOG_FILE = "/cache/recovery/log";
@@ -342,22 +343,95 @@
sync(); // For good measure.
}
+typedef struct _saved_log_file {
+ char* name;
+ struct stat st;
+ unsigned char* data;
+ struct _saved_log_file* next;
+} saved_log_file;
+
static int
erase_volume(const char *volume) {
+ bool is_cache = (strcmp(volume, CACHE_ROOT) == 0);
+
ui->SetBackground(RecoveryUI::ERASING);
ui->SetProgressType(RecoveryUI::INDETERMINATE);
+
+ saved_log_file* head = NULL;
+
+ if (is_cache) {
+ // If we're reformatting /cache, we load any
+ // "/cache/recovery/last*" files into memory, so we can restore
+ // them after the reformat.
+
+ ensure_path_mounted(volume);
+
+ DIR* d;
+ struct dirent* de;
+ d = opendir(CACHE_LOG_DIR);
+ if (d) {
+ char path[PATH_MAX];
+ strcpy(path, CACHE_LOG_DIR);
+ strcat(path, "/");
+ int path_len = strlen(path);
+ while ((de = readdir(d)) != NULL) {
+ if (strncmp(de->d_name, "last", 4) == 0) {
+ saved_log_file* p = (saved_log_file*) malloc(sizeof(saved_log_file));
+ strcpy(path+path_len, de->d_name);
+ p->name = strdup(path);
+ if (stat(path, &(p->st)) == 0) {
+ // truncate files to 512kb
+ if (p->st.st_size > (1 << 19)) {
+ p->st.st_size = 1 << 19;
+ }
+ p->data = (unsigned char*) malloc(p->st.st_size);
+ FILE* f = fopen(path, "rb");
+ fread(p->data, 1, p->st.st_size, f);
+ fclose(f);
+ p->next = head;
+ head = p;
+ } else {
+ free(p);
+ }
+ }
+ }
+ closedir(d);
+ } else {
+ if (errno != ENOENT) {
+ printf("opendir failed: %s\n", strerror(errno));
+ }
+ }
+ }
+
ui->Print("Formatting %s...\n", volume);
ensure_path_unmounted(volume);
+ int result = format_volume(volume);
- if (strcmp(volume, "/cache") == 0) {
+ if (is_cache) {
+ while (head) {
+ FILE* f = fopen_path(head->name, "wb");
+ if (f) {
+ fwrite(head->data, 1, head->st.st_size, f);
+ fclose(f);
+ chmod(head->name, head->st.st_mode);
+ chown(head->name, head->st.st_uid, head->st.st_gid);
+ }
+ free(head->name);
+ free(head->data);
+ saved_log_file* temp = head->next;
+ free(head);
+ head = temp;
+ }
+
// Any part of the log we'd copied to cache is now gone.
// Reset the pointer so we copy from the beginning of the temp
// log.
tmplog_offset = 0;
+ copy_logs();
}
- return format_volume(volume);
+ return result;
}
static char*
