be a bit more robust to failures in window creation, IPC thread launching, & semaphore non-implemented parts

src/os/core/linux/os_core_linux.c

@@ -1071,7 +1071,7 @@ os_semaphore_alloc(U32 initial_count, U32 max_count, String8 name)
   OS_Handle result = {0};
   if (name.size > 0) {
     // TODO: we need to allocate shared memory to store sem_t
-    NotImplemented;
+    // NotImplemented;
   } else {
     sem_t *s = mmap(0, sizeof(*s), PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
     AssertAlways(s != MAP_FAILED);

src/raddbg/raddbg_core.c

@@ -12900,6 +12900,10 @@ rd_frame(void)
                 Vec2F32 monitor_dim  = os_dim_from_monitor(monitor);
                 F32 monitor_dpi      = os_dpi_from_monitor(monitor);
                 Vec2F32 window_dim   = v2f32(monitor_dim.x*4/5, monitor_dim.y*4/5);
+                if(window_dim.x == 0 || window_dim.y == 0)
+                {
+                  window_dim = v2f32(1280, 720);
+                }
                 RD_Cfg *new_window = rd_cfg_new(file_root, str8_lit("window"));
                 RD_Cfg *size = rd_cfg_new(new_window, str8_lit("size"));
                 rd_cfg_newf(size, "%f", window_dim.x);

src/raddbg/raddbg_main.c

@@ -528,8 +528,11 @@ entry_point(CmdLine *cmd_line)
         ipc_s2m_ring_mutex = os_mutex_alloc();
         ipc_s2m_ring_cv = os_condition_variable_alloc();
         IPCInfo *ipc_info = (IPCInfo *)ipc_shared_memory_base;
-        MemoryZeroStruct(ipc_info);
-        os_thread_launch(ipc_signaler_thread__entry_point, 0, 0);
+        if(ipc_shared_memory_base != 0)
+        {
+          MemoryZeroStruct(ipc_info);
+          os_thread_launch(ipc_signaler_thread__entry_point, 0, 0);
+        }
         scratch_end(scratch);
       }