8285362: unify os::pause platform coding

Reviewed-by: dholmes, lucy

src/hotspot/os/aix/os_aix.cpp

@@ -2805,26 +2805,6 @@ int os::loadavg(double values[], int nelem) {
   }
 }
 
-void os::pause() {
-  char filename[MAX_PATH];
-  if (PauseAtStartupFile && PauseAtStartupFile[0]) {
-    jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
-  } else {
-    jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
-  }
-
-  int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
-  if (fd != -1) {
-    struct stat buf;
-    ::close(fd);
-    while (::stat(filename, &buf) == 0) {
-      (void)::poll(NULL, 0, 100);
-    }
-  } else {
-    trcVerbose("Could not open pause file '%s', continuing immediately.", filename);
-  }
-}
-
 bool os::is_primordial_thread(void) {
   if (pthread_self() == (pthread_t)1) {
     return true;

src/hotspot/os/bsd/os_bsd.cpp

@@ -2446,27 +2446,6 @@ int os::loadavg(double loadavg[], int nelem) {
   return ::getloadavg(loadavg, nelem);
 }
 
-void os::pause() {
-  char filename[MAX_PATH];
-  if (PauseAtStartupFile && PauseAtStartupFile[0]) {
-    jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
-  } else {
-    jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
-  }
-
-  int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
-  if (fd != -1) {
-    struct stat buf;
-    ::close(fd);
-    while (::stat(filename, &buf) == 0) {
-      (void)::poll(NULL, 0, 100);
-    }
-  } else {
-    jio_fprintf(stderr,
-                "Could not open pause file '%s', continuing immediately.\n", filename);
-  }
-}
-
 // Get the kern.corefile setting, or otherwise the default path to the core file
 // Returns the length of the string
 int os::get_core_path(char* buffer, size_t bufferSize) {

src/hotspot/os/linux/os_linux.cpp

@@ -5116,27 +5116,6 @@ int os::loadavg(double loadavg[], int nelem) {
   return ::getloadavg(loadavg, nelem);
 }
 
-void os::pause() {
-  char filename[MAX_PATH];
-  if (PauseAtStartupFile && PauseAtStartupFile[0]) {
-    jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
-  } else {
-    jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
-  }
-
-  int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
-  if (fd != -1) {
-    struct stat buf;
-    ::close(fd);
-    while (::stat(filename, &buf) == 0) {
-      (void)::poll(NULL, 0, 100);
-    }
-  } else {
-    jio_fprintf(stderr,
-                "Could not open pause file '%s', continuing immediately.\n", filename);
-  }
-}
-
 // Get the default path to the core file
 // Returns the length of the string
 int os::get_core_path(char* buffer, size_t bufferSize) {

src/hotspot/os/windows/os_windows.cpp

@@ -5150,27 +5150,6 @@ bool os::pd_unmap_memory(char* addr, size_t bytes) {
   return true;
 }
 
-void os::pause() {
-  char filename[MAX_PATH];
-  if (PauseAtStartupFile && PauseAtStartupFile[0]) {
-    jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
-  } else {
-    jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
-  }
-
-  int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
-  if (fd != -1) {
-    struct stat buf;
-    ::close(fd);
-    while (::stat(filename, &buf) == 0) {
-      Sleep(100);
-    }
-  } else {
-    jio_fprintf(stderr,
-                "Could not open pause file '%s', continuing immediately.\n", filename);
-  }
-}
-
 Thread* os::ThreadCrashProtection::_protected_thread = NULL;
 os::ThreadCrashProtection* os::ThreadCrashProtection::_crash_protection = NULL;
 

src/hotspot/share/runtime/os.cpp

@@ -72,6 +72,10 @@
 #include "utilities/events.hpp"
 #include "utilities/powerOfTwo.hpp"
 
+#ifndef _WINDOWS
+# include <poll.h>
+#endif
+
 # include <signal.h>
 # include <errno.h>
 
@@ -1416,6 +1420,35 @@ size_t os::page_size_for_region_unaligned(size_t region_size, size_t min_pages)
   return page_size_for_region(region_size, min_pages, false);
 }
 
+#ifndef MAX_PATH
+#define MAX_PATH    (2 * K)
+#endif
+
+void os::pause() {
+  char filename[MAX_PATH];
+  if (PauseAtStartupFile && PauseAtStartupFile[0]) {
+    jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
+  } else {
+    jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
+  }
+
+  int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
+  if (fd != -1) {
+    struct stat buf;
+    ::close(fd);
+    while (::stat(filename, &buf) == 0) {
+#if defined(_WINDOWS)
+      Sleep(100);
+#else
+      (void)::poll(NULL, 0, 100);
+#endif
+    }
+  } else {
+    jio_fprintf(stderr,
+                "Could not open pause file '%s', continuing immediately.\n", filename);
+  }
+}
+
 static const char* errno_to_string (int e, bool short_text) {
   #define ALL_SHARED_ENUMS(X) \
     X(E2BIG, "Argument list too long") \