chore(3p/nix): apply google-readability-casting

Command run: jq <compile_commands.json -r 'map(.file)|.[]' | grep -v '/generated/' | parallel clang-tidy -p compile_commands.json -checks=-*,google-readability-casting --fix

Manual fixes applied in src/nix-env/nix-env.cc, src/libstore/store-api.cc

Change-Id: I406b4be9368c557ca59329bf6f7002704e955f8d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/1557
Tested-by: BuildkiteCI
Reviewed-by: glittershark <grfn@gws.fyi>
Reviewed-by: tazjin <mail@tazj.in>

third_party/nix/src/libutil/archive.cc

@@ -80,7 +80,7 @@ static void dump(const Path& path, Sink& sink, PathFilter& filter) {
       sink << "executable"
            << "";
     }
-    dumpContents(path, (size_t)st.st_size, sink);
+    dumpContents(path, static_cast<size_t>(st.st_size), sink);
   }
 
   else if (S_ISDIR(st.st_mode)) {
@@ -170,7 +170,7 @@ static void parseContents(ParseSink& sink, Source& source, const Path& path) {
   while (left != 0u) {
     checkInterrupt();
     auto n = buf.size();
-    if ((unsigned long long)n > left) {
+    if (static_cast<unsigned long long>(n) > left) {
       n = left;
     }
     source(buf.data(), n);
@@ -267,7 +267,7 @@ static void parse(ParseSink& sink, Source& source, const Path& path) {
           name = readString(source);
           if (name.empty() || name == "." || name == ".." ||
               name.find('/') != std::string::npos ||
-              name.find((char)0) != std::string::npos) {
+              name.find(static_cast<char>(0)) != std::string::npos) {
             throw Error(format("NAR contains invalid file name '%1%'") % name);
           }
           if (name <= prevName) {

third_party/nix/src/libutil/args.cc

@@ -27,12 +27,12 @@ void Args::parseCmdline(const Strings& _cmdline) {
        `-j3` -> `-j 3`). */
     if (!dashDash && arg.length() > 2 && arg[0] == '-' && arg[1] != '-' &&
         (isalpha(arg[1]) != 0)) {
-      *pos = (std::string) "-" + arg[1];
+      *pos = std::string("-") + arg[1];
       auto next = pos;
       ++next;
       for (unsigned int j = 2; j < arg.length(); j++) {
         if (isalpha(arg[j]) != 0) {
-          cmdline.insert(next, (std::string) "-" + arg[j]);
+          cmdline.insert(next, std::string("-") + arg[j]);
         } else {
           cmdline.insert(next, std::string(arg, j));
           break;

third_party/nix/src/libutil/compression.cc

@@ -99,7 +99,7 @@ struct BzipDecompressionSink : ChunkedCompressionSink {
       throw CompressionError("unable to initialise bzip2 decoder");
     }
 
-    strm.next_out = (char*)outbuf;
+    strm.next_out = reinterpret_cast<char*>(outbuf);
     strm.avail_out = sizeof(outbuf);
   }
 
@@ -128,7 +128,7 @@ struct BzipDecompressionSink : ChunkedCompressionSink {
 
       if (strm.avail_out < sizeof(outbuf) || strm.avail_in == 0) {
         nextSink(outbuf, sizeof(outbuf) - strm.avail_out);
-        strm.next_out = (char*)outbuf;
+        strm.next_out = reinterpret_cast<char*>(outbuf);
         strm.avail_out = sizeof(outbuf);
       }
     }
@@ -287,7 +287,7 @@ struct BzipCompressionSink : ChunkedCompressionSink {
       throw CompressionError("unable to initialise bzip2 encoder");
     }
 
-    strm.next_out = (char*)outbuf;
+    strm.next_out = reinterpret_cast<char*>(outbuf);
     strm.avail_out = sizeof(outbuf);
   }
 
@@ -316,7 +316,7 @@ struct BzipCompressionSink : ChunkedCompressionSink {
 
       if (strm.avail_out < sizeof(outbuf) || strm.avail_in == 0) {
         nextSink(outbuf, sizeof(outbuf) - strm.avail_out);
-        strm.next_out = (char*)outbuf;
+        strm.next_out = reinterpret_cast<char*>(outbuf);
         strm.avail_out = sizeof(outbuf);
       }
     }

third_party/nix/src/libutil/hash.cc

@@ -166,7 +166,7 @@ static std::string printHash32(const Hash& hash) {
   std::string s;
   s.reserve(len);
 
-  for (int n = (int)len - 1; n >= 0; n--) {
+  for (int n = static_cast<int>(len) - 1; n >= 0; n--) {
     unsigned int b = n * 5;
     unsigned int i = b / 8;
     unsigned int j = b % 8;
@@ -199,7 +199,8 @@ std::string Hash::to_string(Base base, bool includeType) const {
     case Base64:
     case SRI:
       std::string b64;
-      absl::Base64Escape(std::string((const char*)hash, hashSize), &b64);
+      absl::Base64Escape(
+          std::string(reinterpret_cast<const char*>(hash), hashSize), &b64);
       s += b64;
       break;
   }
@@ -366,7 +367,7 @@ Hash hashString(HashType ht, const std::string& s) {
   hash::Ctx ctx{};
   Hash hash(ht);
   start(ht, ctx);
-  update(ht, ctx, (const unsigned char*)s.data(), s.length());
+  update(ht, ctx, reinterpret_cast<const unsigned char*>(s.data()), s.length());
   finish(ht, ctx, hash.hash);
   return hash;
 }

third_party/nix/src/libutil/json.cc

@@ -18,7 +18,7 @@ void toJSON(std::ostream& str, const char* start, const char* end) {
       str << "\\t";
     } else if (*i >= 0 && *i < 32) {
       str << "\\u" << std::setfill('0') << std::setw(4) << std::hex
-          << (uint16_t)*i << std::dec;
+          << static_cast<uint16_t>(*i) << std::dec;
     } else {
       str << *i;
     }

third_party/nix/src/libutil/serialise.cc

@@ -96,7 +96,7 @@ std::string Source::drain() {
     size_t n;
     try {
       n = read(buf.data(), buf.size());
-      s.append((char*)buf.data(), n);
+      s.append(reinterpret_cast<char*>(buf.data()), n);
     } catch (EndOfFile&) {
       break;
     }
@@ -129,7 +129,7 @@ size_t FdSource::readUnbuffered(unsigned char* data, size_t len) {
   ssize_t n;
   do {
     checkInterrupt();
-    n = ::read(fd, (char*)data, len);
+    n = ::read(fd, reinterpret_cast<char*>(data), len);
   } while (n == -1 && errno == EINTR);
   if (n == -1) {
     _good = false;
@@ -149,7 +149,7 @@ size_t StringSource::read(unsigned char* data, size_t len) {
   if (pos == s.size()) {
     throw EndOfFile("end of string reached");
   }
-  size_t n = s.copy((char*)data, len, pos);
+  size_t n = s.copy(reinterpret_cast<char*>(data), len, pos);
   pos += n;
   return n;
 }
@@ -179,7 +179,7 @@ std::unique_ptr<Source> sinkToSource(const std::function<void(Sink&)>& fun,
         coro = coro_t::pull_type([&](coro_t::push_type& yield) {
           LambdaSink sink([&](const unsigned char* data, size_t len) {
             if (len != 0u) {
-              yield(std::string((const char*)data, len));
+              yield(std::string(reinterpret_cast<const char*>(data), len));
             }
           });
           fun(sink);
@@ -200,7 +200,7 @@ std::unique_ptr<Source> sinkToSource(const std::function<void(Sink&)>& fun,
       }
 
       auto n = std::min(cur.size() - pos, len);
-      memcpy(data, (unsigned char*)cur.data() + pos, n);
+      memcpy(data, reinterpret_cast<unsigned char*>(cur.data()) + pos, n);
       pos += n;
 
       return n;
@@ -225,7 +225,7 @@ void writeString(const unsigned char* buf, size_t len, Sink& sink) {
 }
 
 Sink& operator<<(Sink& sink, const std::string& s) {
-  writeString((const unsigned char*)s.data(), s.size(), sink);
+  writeString(reinterpret_cast<const unsigned char*>(s.data()), s.size(), sink);
   return sink;
 }
 
@@ -276,7 +276,7 @@ std::string readString(Source& source, size_t max) {
     throw SerialisationError("string is too long");
   }
   std::string res(len, 0);
-  source((unsigned char*)res.data(), len);
+  source(reinterpret_cast<unsigned char*>(res.data()), len);
   readPadding(len, source);
   return res;
 }
@@ -305,7 +305,7 @@ void StringSink::operator()(const unsigned char* data, size_t len) {
     warnLargeDump();
     warned = true;
   }
-  s->append((const char*)data, len);
+  s->append(reinterpret_cast<const char*>(data), len);
 }
 
 }  // namespace nix

third_party/nix/src/libutil/util.cc

@@ -308,7 +308,7 @@ std::string readFile(int fd) {
   std::vector<unsigned char> buf(st.st_size);
   readFull(fd, buf.data(), st.st_size);
 
-  return std::string((char*)buf.data(), st.st_size);
+  return std::string(reinterpret_cast<char*>(buf.data()), st.st_size);
 }
 
 std::string readFile(absl::string_view path, bool drain) {
@@ -349,7 +349,7 @@ void writeFile(const Path& path, Source& source, mode_t mode) {
   while (true) {
     try {
       auto n = source.read(buf.data(), buf.size());
-      writeFull(fd.get(), (unsigned char*)buf.data(), n);
+      writeFull(fd.get(), static_cast<unsigned char*>(buf.data()), n);
     } catch (EndOfFile&) {
       break;
     }
@@ -619,7 +619,7 @@ void replaceSymlink(const Path& target, const Path& link) {
 void readFull(int fd, unsigned char* buf, size_t count) {
   while (count != 0u) {
     checkInterrupt();
-    ssize_t res = read(fd, (char*)buf, count);
+    ssize_t res = read(fd, reinterpret_cast<char*>(buf), count);
     if (res == -1) {
       if (errno == EINTR) {
         continue;
@@ -652,7 +652,8 @@ void writeFull(int fd, const unsigned char* buf, size_t count,
 }
 
 void writeFull(int fd, const std::string& s, bool allowInterrupts) {
-  writeFull(fd, (const unsigned char*)s.data(), s.size(), allowInterrupts);
+  writeFull(fd, reinterpret_cast<const unsigned char*>(s.data()), s.size(),
+            allowInterrupts);
 }
 
 std::string drainFD(int fd, bool block) {
@@ -954,7 +955,7 @@ pid_t startProcess(std::function<void()> fun, const ProcessOptions& options) {
 std::vector<char*> stringsToCharPtrs(const Strings& ss) {
   std::vector<char*> res;
   for (auto& s : ss) {
-    res.push_back((char*)s.c_str());
+    res.push_back(const_cast<char*>(s.c_str()));
   }
   res.push_back(nullptr);
   return res;
@@ -1270,7 +1271,7 @@ std::string filterANSIEscapes(const std::string& s, bool filterAll,
   size_t w = 0;
   auto i = s.begin();
 
-  while (w < (size_t)width && i != s.end()) {
+  while (w < static_cast<size_t>(width) && i != s.end()) {
     if (*i == '\e') {
       std::string e;
       e += *i++;
@@ -1305,7 +1306,7 @@ std::string filterANSIEscapes(const std::string& s, bool filterAll,
       i++;
       t += ' ';
       w++;
-      while (w < (size_t)width && ((w % 8) != 0u)) {
+      while (w < static_cast<size_t>(width) && ((w % 8) != 0u)) {
         t += ' ';
         w++;
       }