Add a fd_readable(int fd) helper function

Use it instead of direct calls to select scatered around the code
base.

src/buffer_utils.cc

@@ -4,9 +4,6 @@
 #include "event_manager.hh"
 #include "file.hh"
 
-#include <unistd.h>
-#include <sys/select.h>
-
 #if defined(__APPLE__)
 #define st_mtim st_mtimespec
 #endif
@@ -120,8 +117,6 @@ Buffer* create_fifo_buffer(String name, int fd, bool scroll)
         size_t loops = 16;
         char data[buffer_size];
         const int fifo = watcher.fd();
-        timeval tv{ 0, 0 };
-        fd_set  rfds;
         ssize_t count = 0;
         do
         {
@@ -142,12 +137,8 @@ Buffer* create_fifo_buffer(String name, int fd, bool scroll)
                 if (data[count-1] == '\n')
                     buffer->insert(buffer->end_coord(), "\n");
             }
-
-            FD_ZERO(&rfds);
-            FD_SET(fifo, &rfds);
         }
-        while (--loops and count > 0 and
-               select(fifo+1, &rfds, nullptr, nullptr, &tv) == 1);
+        while (--loops and count > 0 and fd_readable(fifo));
 
         buffer->run_hook_in_own_context("BufReadFifo", buffer->name());
 

src/file.cc

@@ -13,6 +13,7 @@
 #include <unistd.h>
 #include <dirent.h>
 #include <stdlib.h>
+#include <sys/select.h>
 
 #if defined(__FreeBSD__)
 #include <sys/sysctl.h>
@@ -123,6 +124,16 @@ String compact_path(StringView filename)
     return filename.str();
 }
 
+bool fd_readable(int fd)
+{
+    fd_set  rfds;
+    FD_ZERO(&rfds);
+    FD_SET(fd, &rfds);
+
+    timeval tv{0,0};
+    return select(fd+1, &rfds, nullptr, nullptr, &tv) == 1;
+}
+
 String read_fd(int fd, bool text)
 {
     String content;

src/file.hh

@@ -40,6 +40,7 @@ std::pair<StringView, StringView> split_path(StringView path);
 
 String get_kak_binary_path();
 
+bool fd_readable(int fd);
 String read_fd(int fd, bool text = false);
 String read_file(StringView filename, bool text = false);
 void write(int fd, StringView data);

src/json_ui.cc

@@ -399,24 +399,11 @@ void JsonUI::eval_json(const Value& json)
         throw runtime_error("unknown method");
 }
 
-static bool stdin_ready()
-{
-    fd_set  rfds;
-    FD_ZERO(&rfds);
-    FD_SET(0, &rfds);
-
-    timeval tv;
-    tv.tv_sec = 0;
-    tv.tv_usec = 0;
-
-    return select(1, &rfds, nullptr, nullptr, &tv) == 1;
-}
-
 void JsonUI::parse_requests(EventMode mode)
 {
     constexpr size_t bufsize = 1024;
     char buf[bufsize];
-    while (stdin_ready())
+    while (fd_readable(0))
     {
         ssize_t size = ::read(0, buf, bufsize);
         if (size == -1 or size == 0)

src/remote.cc

@@ -372,17 +372,7 @@ void RemoteUI::set_ui_options(const Options& options)
 
 bool RemoteUI::is_key_available()
 {
-    timeval tv;
-    fd_set  rfds;
-
-    int sock = m_socket_watcher.fd();
-    FD_ZERO(&rfds);
-    FD_SET(sock, &rfds);
-
-    tv.tv_sec = 0;
-    tv.tv_usec = 0;
-    int res = select(sock+1, &rfds, nullptr, nullptr, &tv);
-    return res == 1;
+    return fd_readable(m_socket_watcher.fd());
 }
 
 Key RemoteUI::get_key()
@@ -466,15 +456,9 @@ RemoteClient::RemoteClient(StringView session, std::unique_ptr<UserInterface>&&
 void RemoteClient::process_available_messages()
 {
     int socket = m_socket_watcher->fd();
-    timeval tv{ 0, 0 };
-    fd_set  rfds;
-
     do {
         process_next_message();
-
-        FD_ZERO(&rfds);
-        FD_SET(socket, &rfds);
-    } while (select(socket+1, &rfds, nullptr, nullptr, &tv) == 1);
+    } while (fd_readable(socket));
 }
 
 void RemoteClient::process_next_message()
@@ -573,9 +557,7 @@ public:
 private:
     void handle_available_input()
     {
-        int socket = m_socket_watcher.fd();
-        timeval tv{ 0, 0 };
-        fd_set  rfds;
+        const int socket = m_socket_watcher.fd();
         do
         {
             char c;
@@ -610,11 +592,8 @@ private:
             }
             else
                 m_buffer += c;
-
-            FD_ZERO(&rfds);
-            FD_SET(socket, &rfds);
         }
-        while (select(socket+1, &rfds, nullptr, nullptr, &tv) == 1);
+        while (fd_readable(socket));
     }
 
     String    m_buffer;