[libc] init uefi os target

Author: RossComputerGuy

libc/cmake/modules/LLVMLibCArchitectures.cmake

@@ -69,6 +69,10 @@ function(get_arch_and_system_from_triple triple arch_var sys_var)
     set(target_sys "darwin")
   endif()
 
+  if(target_sys STREQUAL "unknown")
+    list(GET triple_comps -1 target_sys)
+  endif()
+
   # Setting OS name for GPU architectures.
   list(GET triple_comps -1 gpu_target_sys)
   if(gpu_target_sys MATCHES "^amdhsa" OR gpu_target_sys MATCHES "^cuda")
@@ -187,6 +191,8 @@ elseif(LIBC_TARGET_OS STREQUAL "windows")
   set(LIBC_TARGET_OS_IS_WINDOWS TRUE)
 elseif(LIBC_TARGET_OS STREQUAL "gpu")
   set(LIBC_TARGET_OS_IS_GPU TRUE)
+elseif(LIBC_TARGET_OS STREQUAL "uefi")
+  set(LIBC_TARGET_OS_IS_UEFI TRUE)
 else()
   message(FATAL_ERROR
           "Unsupported libc target operating system ${LIBC_TARGET_OS}")

libc/config/uefi/config.json

@@ -0,0 +1,29 @@
+{
+  "errno": {
+    "LIBC_CONF_ERRNO_MODE": {
+      "value": "LIBC_ERRNO_MODE_DEFAULT"
+    }
+  },
+  "printf": {
+    "LIBC_CONF_PRINTF_DISABLE_FLOAT": {
+      "value": true
+    },
+    "LIBC_CONF_PRINTF_DISABLE_INDEX_MODE": {
+      "value": true
+    },
+    "LIBC_CONF_PRINTF_DISABLE_WRITE_INT": {
+      "value": true
+    },
+    "LIBC_CONF_PRINTF_FLOAT_TO_STR_USE_MEGA_LONG_DOUBLE_TABLE": {
+      "value": false
+    },
+    "LIBC_CONF_PRINTF_DISABLE_STRERROR": {
+      "value": true
+    }
+  },
+  "qsort": {
+    "LIBC_CONF_QSORT_IMPL": {
+      "value": "LIBC_QSORT_HEAP_SORT"
+    }
+  }
+}