daemon: Avoid kill -1 bug on the Hurd.

[jackhill/guix/guix.git] / nix / libutil / util.cc

diff --git a/nix/libutil/util.cc b/nix/libutil/util.cc
index dab4235..17d145b 100644 (file)
--- a/nix/libutil/util.cc
+++ b/nix/libutil/util.cc
@@ -177,8 +177,13 @@ struct stat lstat(const Path & path)
 bool pathExists(const Path & path)
 {
     int res;
+#ifdef HAVE_STATX
+    struct statx st;
+    res = statx(AT_FDCWD, path.c_str(), AT_SYMLINK_NOFOLLOW, 0, &st);
+#else
     struct stat st;
     res = lstat(path.c_str(), &st);
+#endif
     if (!res) return true;
     if (errno != ENOENT && errno != ENOTDIR)
         throw SysError(format("getting status of %1%") % path);
@@ -300,16 +305,27 @@ void writeLine(int fd, string s)
 }
 
 
-static void _deletePath(const Path & path, unsigned long long & bytesFreed)
+static void _deletePath(const Path & path, unsigned long long & bytesFreed, size_t linkThreshold)
 {
     checkInterrupt();
 
     printMsg(lvlVomit, format("%1%") % path);
 
+#ifdef HAVE_STATX
+# define st_mode stx_mode
+# define st_size stx_size
+# define st_nlink stx_nlink
+    struct statx st;
+    if (statx(AT_FDCWD, path.c_str(),
+             AT_SYMLINK_NOFOLLOW,
+             STATX_SIZE | STATX_NLINK | STATX_MODE, &st) == -1)
+       throw SysError(format("getting status of `%1%'") % path);
+#else
     struct stat st = lstat(path);
+#endif
 
-    if (!S_ISDIR(st.st_mode) && st.st_nlink == 1)
-        bytesFreed += st.st_blocks * 512;
+    if (!S_ISDIR(st.st_mode) && st.st_nlink <= linkThreshold)
+       bytesFreed += st.st_size;
 
     if (S_ISDIR(st.st_mode)) {
         /* Make the directory writable. */
@@ -319,8 +335,11 @@ static void _deletePath(const Path & path, unsigned long long & bytesFreed)
         }
 
         for (auto & i : readDirectory(path))
-            _deletePath(path + "/" + i.name, bytesFreed);
+            _deletePath(path + "/" + i.name, bytesFreed, linkThreshold);
     }
+#undef st_mode
+#undef st_size
+#undef st_nlink
 
     if (remove(path.c_str()) == -1)
         throw SysError(format("cannot unlink `%1%'") % path);
@@ -334,12 +353,12 @@ void deletePath(const Path & path)
 }
 
 
-void deletePath(const Path & path, unsigned long long & bytesFreed)
+void deletePath(const Path & path, unsigned long long & bytesFreed, size_t linkThreshold)
 {
     startNest(nest, lvlDebug,
         format("recursively deleting path `%1%'") % path);
     bytesFreed = 0;
-    _deletePath(path, bytesFreed);
+    _deletePath(path, bytesFreed, linkThreshold);
 }
 
 
@@ -433,7 +452,7 @@ Nest::~Nest()
 
 static string escVerbosity(Verbosity level)
 {
-    return int2String((int) level);
+    return std::to_string((int) level);
 }
 
 
@@ -842,6 +861,10 @@ void killUser(uid_t uid)
                which means "follow POSIX", which we don't want here
                  */
             if (syscall(SYS_kill, -1, SIGKILL, false) == 0) break;
+#elif __GNU__
+            /* Killing all a user's processes using PID=-1 does currently
+               not work on the Hurd.  */
+            if (kill(getpid(), SIGKILL) == 0) break;
 #else
             if (kill(-1, SIGKILL) == 0) break;
 #endif
@@ -854,6 +877,10 @@ void killUser(uid_t uid)
     });
 
     int status = pid.wait(true);
+#if __GNU__
+    /* When the child killed itself, status = SIGKILL.  */
+    if (status == SIGKILL) return;
+#endif
     if (status != 0)
         throw Error(format("cannot kill processes for uid `%1%': %2%") % uid % statusToString(status));
 
@@ -897,10 +924,10 @@ pid_t startProcess(std::function<void()> fun,
 }
 
 
-std::vector<const char *> stringsToCharPtrs(const Strings & ss)
+std::vector<char *> stringsToCharPtrs(const Strings & ss)
 {
-    std::vector<const char *> res;
-    for (auto & s : ss) res.push_back(s.c_str());
+    std::vector<char *> res;
+    for (auto & s : ss) res.push_back((char *) s.c_str());
     res.push_back(0);
     return res;
 }
@@ -921,12 +948,11 @@ string runProgram(Path program, bool searchPath, const Strings & args)
 
         Strings args_(args);
         args_.push_front(program);
-        auto cargs = stringsToCharPtrs(args_);
 
         if (searchPath)
-            execvp(program.c_str(), (char * *) &cargs[0]);
+            execvp(program.c_str(), stringsToCharPtrs(args_).data());
         else
-            execv(program.c_str(), (char * *) &cargs[0]);
+            execv(program.c_str(), stringsToCharPtrs(args_).data());
 
         throw SysError(format("executing `%1%'") % program);
     });
@@ -1107,21 +1133,6 @@ bool endOfList(std::istream & str)
 }
 
 
-string decodeOctalEscaped(const string & s)
-{
-    string r;
-    for (string::const_iterator i = s.begin(); i != s.end(); ) {
-        if (*i != '\\') { r += *i++; continue; }
-        unsigned char c = 0;
-        ++i;
-        while (i != s.end() && *i >= '0' && *i < '8')
-            c = c * 8 + (*i++ - '0');
-        r += c;
-    }
-    return r;
-}
-
-
 void ignoreException()
 {
     try {