#include <cerrno> #include <map> #include <sys/types.h> #include <sys/stat.h> #include <unistd.h> #include <dirent.h> #include <fcntl.h> #include "references.hh" #include "hash.hh" static void search(const string & s, Strings & ids, Strings & seen) { for (Strings::iterator i = ids.begin(); i != ids.end(); ) { if (s.find(*i) == string::npos) i++; else { debug(format("found reference to `%1%'") % *i); seen.push_back(*i); i = ids.erase(i); } } } void checkPath(const string & path, Strings & ids, Strings & seen) { struct stat st; if (lstat(path.c_str(), &st)) throw SysError(format("getting attributes of path `%1%'") % path); if (S_ISDIR(st.st_mode)) { Strings names = readDirectory(path); for (Strings::iterator i = names.begin(); i != names.end(); i++) { search(*i, ids, seen); checkPath(path + "/" + *i, ids, seen); } } else if (S_ISREG(st.st_mode)) { debug(format("checking `%1%'") % path); AutoCloseFD fd = open(path.c_str(), O_RDONLY); if (fd == -1) throw SysError(format("opening file `%1%'") % path); unsigned char * buf = new unsigned char[st.st_size]; readFull(fd, buf, st.st_size); search(string((char *) buf, st.st_size), ids, seen); delete buf; /* !!! autodelete */ } else if (S_ISLNK(st.st_mode)) search(readLink(path), ids, seen); else throw Error(format("unknown file type: %1%") % path); } Strings filterReferences(const string & path, const Strings & paths) { map<string, string> backMap; Strings ids; Strings seen; /* For efficiency (and a higher hit rate), just search for the hash part of the file name. (This assumes that all references have the form `HASH-bla'). */ for (Strings::const_iterator i = paths.begin(); i != paths.end(); i++) { string s = string(baseNameOf(*i), 0, 32); parseHash(s); ids.push_back(s); backMap[s] = *i; } checkPath(path, ids, seen); Strings found; for (Strings::iterator i = seen.begin(); i != seen.end(); i++) { map<string, string>::iterator j; if ((j = backMap.find(*i)) == backMap.end()) abort(); found.push_back(j->second); } return found; }