[common/client] platform: add portable worker primitives

common/include/common/random.h

@@ -0,0 +1,29 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2026 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _H_LG_COMMON_RANDOM_
+#define _H_LG_COMMON_RANDOM_
+
+#include <stdbool.h>
+#include <stddef.h>
+
+bool lgRandomBytes(void * buffer, size_t size);
+
+#endif

common/include/common/semaphore.h

@@ -0,0 +1,33 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2026 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _H_LG_COMMON_SEMAPHORE_
+#define _H_LG_COMMON_SEMAPHORE_
+
+#include <stdbool.h>
+
+typedef struct LGSemaphore LGSemaphore;
+
+LGSemaphore * lgCreateSemaphore(unsigned int initialValue);
+void          lgFreeSemaphore  (LGSemaphore * semaphore);
+bool          lgWaitSemaphore  (LGSemaphore * semaphore);
+bool          lgSignalSemaphore(LGSemaphore * semaphore);
+
+#endif

common/src/platform/linux/CMakeLists.txt

@@ -12,6 +12,8 @@ add_library(lg_common_platform_code STATIC
   sysinfo.c
   thread.c
   event.c
+  semaphore.c
+  random.c
   ivshmem.c
   time.c
   paths.c

common/src/platform/linux/random.c

@@ -0,0 +1,43 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2026 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "common/random.h"
+
+#include <errno.h>
+#include <stdint.h>
+#include <sys/random.h>
+
+bool lgRandomBytes(void * buffer, size_t size)
+{
+  uint8_t * output = buffer;
+  while (size)
+  {
+    const ssize_t received = getrandom(output, size, 0);
+    if (received < 0 && errno == EINTR)
+      continue;
+    if (received <= 0)
+      return false;
+
+    output += (size_t)received;
+    size   -= (size_t)received;
+  }
+
+  return true;
+}

common/src/platform/linux/semaphore.c

@@ -0,0 +1,80 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2026 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "common/semaphore.h"
+
+#include "common/debug.h"
+
+#include <errno.h>
+#include <semaphore.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct LGSemaphore
+{
+  sem_t handle;
+};
+
+LGSemaphore * lgCreateSemaphore(unsigned int initialValue)
+{
+  LGSemaphore * semaphore = malloc(sizeof(*semaphore));
+  if (!semaphore)
+    return NULL;
+
+  if (sem_init(&semaphore->handle, 0, initialValue) != 0)
+  {
+    DEBUG_ERROR("Failed to create semaphore: %s", strerror(errno));
+    free(semaphore);
+    return NULL;
+  }
+
+  return semaphore;
+}
+
+void lgFreeSemaphore(LGSemaphore * semaphore)
+{
+  if (!semaphore)
+    return;
+
+  if (sem_destroy(&semaphore->handle) != 0)
+    DEBUG_ERROR("Failed to destroy semaphore: %s", strerror(errno));
+  free(semaphore);
+}
+
+bool lgWaitSemaphore(LGSemaphore * semaphore)
+{
+  int result;
+  do
+    result = sem_wait(&semaphore->handle);
+  while (result != 0 && errno == EINTR);
+
+  if (result != 0)
+    DEBUG_ERROR("Failed to wait on semaphore: %s", strerror(errno));
+  return result == 0;
+}
+
+bool lgSignalSemaphore(LGSemaphore * semaphore)
+{
+  if (sem_post(&semaphore->handle) == 0)
+    return true;
+
+  DEBUG_ERROR("Failed to signal semaphore: %s", strerror(errno));
+  return false;
+}

common/src/platform/windows/CMakeLists.txt

@@ -35,6 +35,8 @@ add_library(lg_common_platform_code STATIC
   sysinfo.c
   thread.c
   event.c
+  semaphore.c
+  random.c
   windebug.c
   ivshmem.c
   time.c
@@ -46,6 +48,7 @@ add_library(lg_common_platform_code STATIC
 target_link_libraries(lg_common_platform_code
   lg_common
   setupapi
+  bcrypt
   ntdll
 )
 

common/src/platform/windows/random.c

@@ -0,0 +1,43 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2026 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "common/random.h"
+
+#include <limits.h>
+#include <stdint.h>
+#include <windows.h>
+#include <bcrypt.h>
+
+bool lgRandomBytes(void * buffer, size_t size)
+{
+  uint8_t * output = buffer;
+  while (size)
+  {
+    const ULONG chunk = size > ULONG_MAX ? ULONG_MAX : (ULONG)size;
+    if (!BCRYPT_SUCCESS(BCryptGenRandom(
+          NULL, output, chunk, BCRYPT_USE_SYSTEM_PREFERRED_RNG)))
+      return false;
+
+    output += chunk;
+    size   -= chunk;
+  }
+
+  return true;
+}

common/src/platform/windows/semaphore.c

@@ -0,0 +1,83 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2026 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "common/semaphore.h"
+
+#include "common/debug.h"
+#include "common/windebug.h"
+
+#include <limits.h>
+#include <stdlib.h>
+#include <windows.h>
+
+struct LGSemaphore
+{
+  HANDLE handle;
+};
+
+LGSemaphore * lgCreateSemaphore(unsigned int initialValue)
+{
+  if (initialValue > (unsigned int)LONG_MAX)
+    return NULL;
+
+  LGSemaphore * semaphore = malloc(sizeof(*semaphore));
+  if (!semaphore)
+    return NULL;
+
+  semaphore->handle = CreateSemaphoreW(
+      NULL, (LONG)initialValue, LONG_MAX, NULL);
+  if (!semaphore->handle)
+  {
+    DEBUG_WINERROR("Failed to create semaphore", GetLastError());
+    free(semaphore);
+    return NULL;
+  }
+
+  return semaphore;
+}
+
+void lgFreeSemaphore(LGSemaphore * semaphore)
+{
+  if (!semaphore)
+    return;
+
+  if (!CloseHandle(semaphore->handle))
+    DEBUG_WINERROR("Failed to destroy semaphore", GetLastError());
+  free(semaphore);
+}
+
+bool lgWaitSemaphore(LGSemaphore * semaphore)
+{
+  const DWORD result = WaitForSingleObject(semaphore->handle, INFINITE);
+  if (result == WAIT_OBJECT_0)
+    return true;
+
+  DEBUG_WINERROR("Failed to wait on semaphore", GetLastError());
+  return false;
+}
+
+bool lgSignalSemaphore(LGSemaphore * semaphore)
+{
+  if (ReleaseSemaphore(semaphore->handle, 1, NULL))
+    return true;
+
+  DEBUG_WINERROR("Failed to signal semaphore", GetLastError());
+  return false;
+}