From ba9a42aa7e10686de186636fe9fecbf8c4cc7c19 Mon Sep 17 00:00:00 2001 From: Tao Bao Date: Tue, 23 Jun 2015 23:23:33 -0700 Subject: recovery: Switch applypatch/ and updater/ to cpp. Mostly trivial changes to make cpp compiler happy. Change-Id: I69bd1d96fcccf506007f6144faf37e11cfba1270 --- applypatch/freecache.cpp | 186 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 186 insertions(+) create mode 100644 applypatch/freecache.cpp (limited to 'applypatch/freecache.cpp') diff --git a/applypatch/freecache.cpp b/applypatch/freecache.cpp new file mode 100644 index 000000000..2eb2f55ef --- /dev/null +++ b/applypatch/freecache.cpp @@ -0,0 +1,186 @@ +/* + * Copyright (C) 2010 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "applypatch.h" + +static int EliminateOpenFiles(char** files, int file_count) { + DIR* d; + struct dirent* de; + d = opendir("/proc"); + if (d == NULL) { + printf("error opening /proc: %s\n", strerror(errno)); + return -1; + } + while ((de = readdir(d)) != 0) { + int i; + for (i = 0; de->d_name[i] != '\0' && isdigit(de->d_name[i]); ++i); + if (de->d_name[i]) continue; + + // de->d_name[i] is numeric + + char path[FILENAME_MAX]; + strcpy(path, "/proc/"); + strcat(path, de->d_name); + strcat(path, "/fd/"); + + DIR* fdd; + struct dirent* fdde; + fdd = opendir(path); + if (fdd == NULL) { + printf("error opening %s: %s\n", path, strerror(errno)); + continue; + } + while ((fdde = readdir(fdd)) != 0) { + char fd_path[FILENAME_MAX]; + char link[FILENAME_MAX]; + strcpy(fd_path, path); + strcat(fd_path, fdde->d_name); + + int count; + count = readlink(fd_path, link, sizeof(link)-1); + if (count >= 0) { + link[count] = '\0'; + + // This is inefficient, but it should only matter if there are + // lots of files in /cache, and lots of them are open (neither + // of which should be true, especially in recovery). + if (strncmp(link, "/cache/", 7) == 0) { + int j; + for (j = 0; j < file_count; ++j) { + if (files[j] && strcmp(files[j], link) == 0) { + printf("%s is open by %s\n", link, de->d_name); + free(files[j]); + files[j] = NULL; + } + } + } + } + } + closedir(fdd); + } + closedir(d); + + return 0; +} + +int FindExpendableFiles(char*** names, int* entries) { + DIR* d; + struct dirent* de; + int size = 32; + *entries = 0; + *names = reinterpret_cast(malloc(size * sizeof(char*))); + + char path[FILENAME_MAX]; + + // We're allowed to delete unopened regular files in any of these + // directories. + const char* dirs[2] = {"/cache", "/cache/recovery/otatest"}; + + for (size_t i = 0; i < sizeof(dirs)/sizeof(dirs[0]); ++i) { + d = opendir(dirs[i]); + if (d == NULL) { + printf("error opening %s: %s\n", dirs[i], strerror(errno)); + continue; + } + + // Look for regular files in the directory (not in any subdirectories). + while ((de = readdir(d)) != 0) { + strcpy(path, dirs[i]); + strcat(path, "/"); + strcat(path, de->d_name); + + // We can't delete CACHE_TEMP_SOURCE; if it's there we might have + // restarted during installation and could be depending on it to + // be there. + if (strcmp(path, CACHE_TEMP_SOURCE) == 0) continue; + + struct stat st; + if (stat(path, &st) == 0 && S_ISREG(st.st_mode)) { + if (*entries >= size) { + size *= 2; + *names = reinterpret_cast(realloc(*names, size * sizeof(char*))); + } + (*names)[(*entries)++] = strdup(path); + } + } + + closedir(d); + } + + printf("%d regular files in deletable directories\n", *entries); + + if (EliminateOpenFiles(*names, *entries) < 0) { + return -1; + } + + return 0; +} + +int MakeFreeSpaceOnCache(size_t bytes_needed) { + size_t free_now = FreeSpaceForFile("/cache"); + printf("%zu bytes free on /cache (%zu needed)\n", free_now, bytes_needed); + + if (free_now >= bytes_needed) { + return 0; + } + + char** names; + int entries; + + if (FindExpendableFiles(&names, &entries) < 0) { + return -1; + } + + if (entries == 0) { + // nothing we can delete to free up space! + printf("no files can be deleted to free space on /cache\n"); + return -1; + } + + // We could try to be smarter about which files to delete: the + // biggest ones? the smallest ones that will free up enough space? + // the oldest? the newest? + // + // Instead, we'll be dumb. + + int i; + for (i = 0; i < entries && free_now < bytes_needed; ++i) { + if (names[i]) { + unlink(names[i]); + free_now = FreeSpaceForFile("/cache"); + printf("deleted %s; now %zu bytes free\n", names[i], free_now); + free(names[i]); + } + } + + for (; i < entries; ++i) { + free(names[i]); + } + free(names); + + return (free_now >= bytes_needed) ? 0 : -1; +} -- cgit v1.2.3