findRuntimeRoots: Simplify/fix handling of /proc files

Scanning of /proc/<pid>/{exe,cwd} was broken because '{memory:' was
prepended twice. Also, get rid of the whole '{memory:...}' thing
because it's unnecessary, we can just list the file in /proc directly.
This commit is contained in:
Eelco Dolstra 2019-03-14 13:27:16 +01:00
parent 115e2c8c67
commit a3f37d87ea
No known key found for this signature in database
GPG key ID: 8170B4726D7198DE
2 changed files with 14 additions and 15 deletions

View file

@ -362,8 +362,7 @@ try_again:
} }
if (res > 0 && buf[0] == '/') if (res > 0 && buf[0] == '/')
roots[std::string(static_cast<char *>(buf), res)] roots[std::string(static_cast<char *>(buf), res)]
.emplace((format("{memory:%1%") % file).str()); .emplace(file);
return;
} }
static string quoteRegexChars(const string & raw) static string quoteRegexChars(const string & raw)
@ -395,10 +394,10 @@ void LocalStore::findRuntimeRoots(Roots & roots)
while (errno = 0, ent = readdir(procDir.get())) { while (errno = 0, ent = readdir(procDir.get())) {
checkInterrupt(); checkInterrupt();
if (std::regex_match(ent->d_name, digitsRegex)) { if (std::regex_match(ent->d_name, digitsRegex)) {
readProcLink((format("{memory:/proc/%1%/exe}") % ent->d_name).str(), unchecked); readProcLink(fmt("/proc/%s/exe" ,ent->d_name), unchecked);
readProcLink((format("{memory:/proc/%1%/cwd}") % ent->d_name).str(), unchecked); readProcLink(fmt("/proc/%s/cwd", ent->d_name), unchecked);
auto fdStr = (format("/proc/%1%/fd") % ent->d_name).str(); auto fdStr = fmt("/proc/%s/fd", ent->d_name);
auto fdDir = AutoCloseDir(opendir(fdStr.c_str())); auto fdDir = AutoCloseDir(opendir(fdStr.c_str()));
if (!fdDir) { if (!fdDir) {
if (errno == ENOENT || errno == EACCES) if (errno == ENOENT || errno == EACCES)
@ -407,9 +406,8 @@ void LocalStore::findRuntimeRoots(Roots & roots)
} }
struct dirent * fd_ent; struct dirent * fd_ent;
while (errno = 0, fd_ent = readdir(fdDir.get())) { while (errno = 0, fd_ent = readdir(fdDir.get())) {
if (fd_ent->d_name[0] != '.') { if (fd_ent->d_name[0] != '.')
readProcLink((format("%1%/%2%") % fdStr % fd_ent->d_name).str(), unchecked); readProcLink(fmt("%s/%s", fdStr, fd_ent->d_name), unchecked);
}
} }
if (errno) { if (errno) {
if (errno == ESRCH) if (errno == ESRCH)
@ -419,19 +417,19 @@ void LocalStore::findRuntimeRoots(Roots & roots)
fdDir.reset(); fdDir.reset();
try { try {
auto mapFile = (format("/proc/%1%/maps") % ent->d_name).str(); auto mapFile = fmt("/proc/%s/maps", ent->d_name);
auto mapLines = tokenizeString<std::vector<string>>(readFile(mapFile, true), "\n"); auto mapLines = tokenizeString<std::vector<string>>(readFile(mapFile, true), "\n");
for (const auto& line : mapLines) { for (const auto & line : mapLines) {
auto match = std::smatch{}; auto match = std::smatch{};
if (std::regex_match(line, match, mapRegex)) if (std::regex_match(line, match, mapRegex))
unchecked[match[1]].emplace((format("{memory:%1%}") % mapFile).str()); unchecked[match[1]].emplace(mapFile);
} }
auto envFile = (format("/proc/%1%/environ") % ent->d_name).str(); auto envFile = fmt("/proc/%s/environ", ent->d_name);
auto envString = readFile(envFile, true); auto envString = readFile(envFile, true);
auto env_end = std::sregex_iterator{}; auto env_end = std::sregex_iterator{};
for (auto i = std::sregex_iterator{envString.begin(), envString.end(), storePathRegex}; i != env_end; ++i) for (auto i = std::sregex_iterator{envString.begin(), envString.end(), storePathRegex}; i != env_end; ++i)
unchecked[i->str()].emplace((format("{memory:%1%}") % envFile).str()); unchecked[i->str()].emplace(envFile);
} catch (SysError & e) { } catch (SysError & e) {
if (errno == ENOENT || errno == EACCES || errno == ESRCH) if (errno == ENOENT || errno == EACCES || errno == ESRCH)
continue; continue;
@ -451,7 +449,7 @@ void LocalStore::findRuntimeRoots(Roots & roots)
for (const auto & line : lsofLines) { for (const auto & line : lsofLines) {
std::smatch match; std::smatch match;
if (std::regex_match(line, match, lsofRegex)) if (std::regex_match(line, match, lsofRegex))
unchecked[match[1]].emplace((format("{memory:%1%}" % LSOF).str()); unchecked[match[1]].emplace("{lsof}");
} }
} catch (ExecError & e) { } catch (ExecError & e) {
/* lsof not installed, lsof failed */ /* lsof not installed, lsof failed */

View file

@ -11,6 +11,7 @@
#include <atomic> #include <atomic>
#include <limits> #include <limits>
#include <map> #include <map>
#include <unordered_set>
#include <memory> #include <memory>
#include <string> #include <string>
@ -47,7 +48,7 @@ const size_t storePathHashLen = 32; // i.e. 160 bits
const uint32_t exportMagic = 0x4558494e; const uint32_t exportMagic = 0x4558494e;
typedef std::map<Path, std::set<std::string>> Roots; typedef std::unordered_map<Path, std::unordered_set<std::string>> Roots;
struct GCOptions struct GCOptions