Make findRuntimeRoots() more resilient to disappearing processes

I saw this random failure in https://hydra.nixos.org/build/211811692:

  error: opening /proc/15307/fd: No such process

while running nix-collect-garbage in a readfile-context.sh. This is
because we're not handling ESRCH errors reading /proc/<pid>/fd. So
just move the read inside the try/catch where we do handle it.
This commit is contained in:
Eelco Dolstra 2023-03-09 16:44:51 +01:00
parent c44750982d
commit 4f3a4b732c

View file

@ -371,6 +371,7 @@ void LocalStore::findRuntimeRoots(Roots & roots, bool censor)
while (errno = 0, ent = readdir(procDir.get())) {
checkInterrupt();
if (std::regex_match(ent->d_name, digitsRegex)) {
try {
readProcLink(fmt("/proc/%s/exe" ,ent->d_name), unchecked);
readProcLink(fmt("/proc/%s/cwd", ent->d_name), unchecked);
@ -393,7 +394,6 @@ void LocalStore::findRuntimeRoots(Roots & roots, bool censor)
}
fdDir.reset();
try {
auto mapFile = fmt("/proc/%s/maps", ent->d_name);
auto mapLines = tokenizeString<std::vector<std::string>>(readFile(mapFile), "\n");
for (const auto & line : mapLines) {