diff options
Diffstat (limited to 'applypatch/freecache.cpp')
| -rw-r--r-- | applypatch/freecache.cpp | 141 |
1 files changed, 49 insertions, 92 deletions
diff --git a/applypatch/freecache.cpp b/applypatch/freecache.cpp index 2eb2f55ef..c84f42797 100644 --- a/applypatch/freecache.cpp +++ b/applypatch/freecache.cpp @@ -25,119 +25,90 @@ #include <dirent.h> #include <ctype.h> +#include <memory> +#include <set> +#include <string> + +#include <android-base/parseint.h> +#include <android-base/stringprintf.h> + #include "applypatch.h" -static int EliminateOpenFiles(char** files, int file_count) { - DIR* d; - struct dirent* de; - d = opendir("/proc"); - if (d == NULL) { +static int EliminateOpenFiles(std::set<std::string>* files) { + std::unique_ptr<DIR, decltype(&closedir)> d(opendir("/proc"), closedir); + if (!d) { 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/"); + struct dirent* de; + while ((de = readdir(d.get())) != 0) { + unsigned int pid; + if (!android::base::ParseUint(de->d_name, &pid)) { + continue; + } + std::string path = android::base::StringPrintf("/proc/%s/fd/", de->d_name); - DIR* fdd; struct dirent* fdde; - fdd = opendir(path); - if (fdd == NULL) { - printf("error opening %s: %s\n", path, strerror(errno)); + std::unique_ptr<DIR, decltype(&closedir)> fdd(opendir(path.c_str()), closedir); + if (!fdd) { + printf("error opening %s: %s\n", path.c_str(), strerror(errno)); continue; } - while ((fdde = readdir(fdd)) != 0) { - char fd_path[FILENAME_MAX]; + while ((fdde = readdir(fdd.get())) != 0) { + std::string fd_path = path + fdde->d_name; char link[FILENAME_MAX]; - strcpy(fd_path, path); - strcat(fd_path, fdde->d_name); - int count; - count = readlink(fd_path, link, sizeof(link)-1); + int count = readlink(fd_path.c_str(), 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; - } + if (files->erase(link) > 0) { + printf("%s is open by %s\n", link, de->d_name); } } } } - 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<char**>(malloc(size * sizeof(char*))); - - char path[FILENAME_MAX]; - +static std::set<std::string> FindExpendableFiles() { + std::set<std::string> files; // 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) { + std::unique_ptr<DIR, decltype(&closedir)> d(opendir(dirs[i]), closedir); + if (!d) { 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); + struct dirent* de; + while ((de = readdir(d.get())) != 0) { + std::string path = std::string(dirs[i]) + "/" + 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; + if (path == CACHE_TEMP_SOURCE) { + continue; + } struct stat st; - if (stat(path, &st) == 0 && S_ISREG(st.st_mode)) { - if (*entries >= size) { - size *= 2; - *names = reinterpret_cast<char**>(realloc(*names, size * sizeof(char*))); - } - (*names)[(*entries)++] = strdup(path); + if (stat(path.c_str(), &st) == 0 && S_ISREG(st.st_mode)) { + files.insert(path); } } - - closedir(d); } - printf("%d regular files in deletable directories\n", *entries); - - if (EliminateOpenFiles(*names, *entries) < 0) { - return -1; + printf("%zu regular files in deletable directories\n", files.size()); + if (EliminateOpenFiles(&files) < 0) { + return std::set<std::string>(); } - - return 0; + return files; } int MakeFreeSpaceOnCache(size_t bytes_needed) { @@ -147,15 +118,8 @@ int MakeFreeSpaceOnCache(size_t bytes_needed) { if (free_now >= bytes_needed) { return 0; } - - char** names; - int entries; - - if (FindExpendableFiles(&names, &entries) < 0) { - return -1; - } - - if (entries == 0) { + std::set<std::string> files = FindExpendableFiles(); + if (files.empty()) { // nothing we can delete to free up space! printf("no files can be deleted to free space on /cache\n"); return -1; @@ -167,20 +131,13 @@ int MakeFreeSpaceOnCache(size_t bytes_needed) { // // 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 (const auto& file : files) { + unlink(file.c_str()); + free_now = FreeSpaceForFile("/cache"); + printf("deleted %s; now %zu bytes free\n", file.c_str(), free_now); + if (free_now < bytes_needed) { + break; } } - - for (; i < entries; ++i) { - free(names[i]); - } - free(names); - return (free_now >= bytes_needed) ? 0 : -1; } |