Bazel client: fix compiler warnings

--
MOS_MIGRATED_REVID=139899429

4 files changed, 20 insertions, 27 deletions

diff --git a/src/main/cpp/blaze_util.cc b/src/main/cpp/blaze_util.cc
index 9e1bd2df38..cfa2b92511 100644
--- a/src/main/cpp/blaze_util.cc
+++ b/src/main/cpp/blaze_util.cc
@@ -77,23 +77,21 @@ string MakeAbsolute(const string &path) {
   return cwd + separator + path;
 }
 
-// Replaces 'contents' with contents of 'fd' file descriptor.
-// If `max_size` is positive, the method reads at most that many bytes; if it
-// is 0, the method reads the whole file.
-// Returns false on error.
-bool ReadFileDescriptor(int fd, string *content, size_t max_size) {
+bool ReadFileDescriptor(int fd, string *content, int max_size) {
   content->clear();
   char buf[4096];
   // OPT:  This loop generates one spurious read on regular files.
-  while (int r = read(fd, buf, max_size > 0 ? std::min(max_size, sizeof buf)
-                                            : sizeof buf)) {
+  while (int r = read(fd, buf,
+                      max_size > 0
+                          ? std::min(max_size, static_cast<int>(sizeof buf))
+                          : sizeof buf)) {
     if (r == -1) {
       if (errno == EINTR || errno == EAGAIN) continue;
       return false;
     }
     content->append(buf, r);
     if (max_size > 0) {
-      if (max_size > static_cast<size_t>(r)) {
+      if (max_size > r) {
         max_size -= r;
       } else {
         break;
@@ -104,11 +102,7 @@ bool ReadFileDescriptor(int fd, string *content, size_t max_size) {
   return true;
 }
 
-// Replaces 'content' with contents of file 'filename'.
-// If `max_size` is positive, the method reads at most that many bytes; if it
-// is 0, the method reads the whole file.
-// Returns false on error.
-bool ReadFile(const string &filename, string *content, size_t max_size) {
+bool ReadFile(const string &filename, string *content, int max_size) {
   int fd = open(filename.c_str(), O_RDONLY);
   if (fd == -1) return false;
   return ReadFileDescriptor(fd, content, max_size);
diff --git a/src/main/cpp/blaze_util.h b/src/main/cpp/blaze_util.h
index 7241682cba..0f7b71a596 100644
--- a/src/main/cpp/blaze_util.h
+++ b/src/main/cpp/blaze_util.h
@@ -42,17 +42,17 @@ std::string GetUserName();
 std::string MakeAbsolute(const std::string &path);
 
 // Replaces 'content' with contents of file 'filename'.
-// If `max_size` is positive, the method reads at most that many bytes; if it
-// is 0, the method reads the whole file.
+// If `max_size` is positive, the method reads at most that many bytes;
+// otherwise the method reads the whole file.
 // Returns false on error. Can be called from a signal handler.
 bool ReadFile(const std::string &filename, std::string *content,
-              size_t max_size = 0);
+              int max_size = 0);
 
 // Replaces 'content' with contents of file descriptor 'fd'.
 // If `max_size` is positive, the method reads at most that many bytes; if it
-// is 0, the method reads the whole file.
+// otherwise the method reads the whole file.
 // Returns false on error. Can be called from a signal handler.
-bool ReadFileDescriptor(int fd, std::string *content, size_t max_size = 0);
+bool ReadFileDescriptor(int fd, std::string *content, int max_size = 0);
 
 // Writes 'content' into file 'filename', and makes it executable.
 // Returns false on failure, sets errno.
diff --git a/src/main/cpp/util/file.h b/src/main/cpp/util/file.h
index 6118eefb0b..13a2b4828c 100644
--- a/src/main/cpp/util/file.h
+++ b/src/main/cpp/util/file.h
@@ -24,11 +24,13 @@ class IPipe {
   virtual ~IPipe() {}
 
   // Sends `size` bytes from `buffer` through the pipe.
-  virtual bool Send(void *buffer, size_t size) = 0;
+  // Returns true if `size` is not negative and could send all the data.
+  virtual bool Send(void *buffer, int size) = 0;
 
   // Receives at most `size` bytes into `buffer` from the pipe.
   // Returns the number of bytes received; sets `errno` upon error.
-  virtual int Receive(void *buffer, size_t size) = 0;
+  // If `size` is negative, returns -1.
+  virtual int Receive(void *buffer, int size) = 0;
 };
 
 // Returns the part of the path before the final "/".  If there is a single
diff --git a/src/main/cpp/util/file_posix.cc b/src/main/cpp/util/file_posix.cc
index 5bb8772d70..08a38cc102 100644
--- a/src/main/cpp/util/file_posix.cc
+++ b/src/main/cpp/util/file_posix.cc
@@ -45,15 +45,12 @@ class PosixPipe : public IPipe {
     close(_send_socket);
   }
 
-  // Sends `size` bytes from `buffer` through the pipe.
-  bool Send(void* buffer, size_t size) override {
-    return write(_send_socket, buffer, size) == size;
+  bool Send(void* buffer, int size) override {
+    return size >= 0 && write(_send_socket, buffer, size) == size;
   }
 
-  // Receives at most `size` bytes into `buffer` from the pipe.
-  // Returns the number of bytes received; sets `errno` upon error.
-  int Receive(void* buffer, size_t size) override {
-    return read(_recv_socket, buffer, size);
+  int Receive(void* buffer, int size) override {
+    return size < 0 ? -1 : read(_recv_socket, buffer, size);
   }
 
  private: