fix build errors on MSYS platform

CMakeLists.txt

@@ -23,6 +23,12 @@ if(CMAKE_SYSTEM_NAME MATCHES "Linux")
   string (REPLACE ";" " " LIBBSD_FLAGS "${BSD_CFLAGS}")
   target_link_libraries (mg ${BSD_LIBRARIES})
   set (CMAKE_C_FLAGS "-Wall -DREGEX -D_GNU_SOURCE ${LIBBSD_FLAGS} ${NCURSES_FLAGS} -L${NCURSES_LIBRARY_DIRS}")
+elseif(CMAKE_SYSTEM_NAME MATCHES "MSYS")
+  pkg_check_modules (BSD REQUIRED libbsd-overlay)
+  link_directories (${BSD_LIBRARY_DIRS})
+  string (REPLACE ";" " " LIBBSD_FLAGS "${BSD_CFLAGS}")
+  target_link_libraries (mg ${BSD_LIBRARIES})
+  set (CMAKE_C_FLAGS "-Wall -DREGEX -isystem /usr/include -D_GNU_SOURCE -DHAVE_PTY_H ${LIBBSD_FLAGS} ${NCURSES_FLAGS}")
 else()
   set (CMAKE_C_FLAGS "-Wall -DREGEX ${LIBBSD_FLAGS} ${NCURSES_FLAGS} -L${NCURSES_LIBRARY_DIRS}")
 endif()

GNUmakefile

@@ -40,6 +40,9 @@ endif
 
 ifdef STATIC
   LDFLAGS=-static -static-libgcc
+  ifneq ($(MSYSTEM),)
+    CURSES_LIBS:= $(CURSES_LIBS).dll
+  endif
 endif
 
 CC?=		gcc

def.h

@@ -789,6 +789,10 @@ extern int		 tcinsl;
 extern int		 tcdell;
 extern int		 rptcount;	/* successive invocation count */
 
+long long strtonum(const char *nptr, long long minval, long long maxval,
+                   const char **errstr);
+
+
 /* https://github.com/hboetes/mg/issues/7#issuecomment-475869095 */
 #if defined(__APPLE__) || defined(__NetBSD__)
 #define st_atim st_atimespec

ttyio.c

@@ -14,6 +14,9 @@
 #include <sys/queue.h>
 #include <sys/time.h>
 #include <sys/types.h>
+#if defined(__MSYS__)
+#include <sys/socket.h>
+#endif
 #include <errno.h>
 #include <fcntl.h>
 #include <poll.h>