Extract StdinReader into a shared header

Author: petrhosek

libc/src/stdio/baremetal/CMakeLists.txt

@@ -55,15 +55,24 @@ add_entrypoint_object(
     libc.src.__support.CPP.string_view
 )
 
+add_header_library(
+  scanf_internal
+  HDRS
+    scanf_internal.h
+  DEPENDS
+    libc.src.stdio.scanf_core.reader
+    libc.src.__support.OSUtil.osutil
+)
+
 add_entrypoint_object(
   scanf
   SRCS
     scanf.cpp
   HDRS
     ../scanf.h
   DEPENDS
+    .scanf_internal
     libc.src.stdio.scanf_core.scanf_main
-    libc.src.stdio.scanf_core.reader
     libc.src.__support.arg_list
     libc.src.__support.OSUtil.osutil
 )
@@ -88,8 +97,8 @@ add_entrypoint_object(
   HDRS
     ../vscanf.h
   DEPENDS
+    .scanf_internal
     libc.src.stdio.scanf_core.scanf_main
-    libc.src.stdio.scanf_core.reader
     libc.src.__support.arg_list
     libc.src.__support.OSUtil.osutil
 )

libc/src/stdio/baremetal/scanf.cpp

@@ -12,28 +12,13 @@
 #include "src/__support/OSUtil/io.h"
 #include "src/__support/arg_list.h"
 #include "src/__support/macros/config.h"
-#include "src/stdio/scanf_core/reader.h"
+#include "src/stdio/baremetal/scanf_internal.h"
 #include "src/stdio/scanf_core/scanf_main.h"
 
 #include <stdarg.h>
 
 namespace LIBC_NAMESPACE_DECL {
 
-namespace {
-
-struct StreamReader : scanf_core::Reader<StreamReader> {
-  LIBC_INLINE char getc() {
-    char buf[1];
-    auto result = read_from_stdin(buf, sizeof(buf));
-    if (result <= 0)
-      return EOF;
-    return buf[0];
-  }
-  LIBC_INLINE void ungetc(int) {}
-};
-
-} // namespace
-
 LLVM_LIBC_FUNCTION(int, scanf, (const char *__restrict format, ...)) {
   va_list vlist;
   va_start(vlist, format);
@@ -42,7 +27,7 @@ LLVM_LIBC_FUNCTION(int, scanf, (const char *__restrict format, ...)) {
                                  // destruction automatically.
   va_end(vlist);
 
-  StreamReader reader;
+  scanf_core::StdinReader reader;
   int retval = scanf_core::scanf_main(&reader, format, args);
   // This is done to avoid including stdio.h in the internals. On most systems
   // EOF is -1, so this will be transformed into just "return retval".

libc/src/stdio/baremetal/vscanf.cpp

@@ -12,36 +12,21 @@
 #include "src/__support/OSUtil/io.h"
 #include "src/__support/arg_list.h"
 #include "src/__support/macros/config.h"
-#include "src/stdio/scanf_core/reader.h"
+#include "src/stdio/baremetal/scanf_internal.h"
 #include "src/stdio/scanf_core/scanf_main.h"
 
 #include <stdarg.h>
 
 namespace LIBC_NAMESPACE_DECL {
 
-namespace {
-
-struct StreamReader : scanf_core::Reader<StreamReader> {
-  LIBC_INLINE char getc() {
-    char buf[1];
-    auto result = read_from_stdin(buf, sizeof(buf));
-    if (result <= 0)
-      return EOF;
-    return buf[0];
-  }
-  LIBC_INLINE void ungetc(int) {}
-};
-
-} // namespace
-
 LLVM_LIBC_FUNCTION(int, vscanf,
                    (const char *__restrict format, va_list vlist)) {
   internal::ArgList args(vlist); // This holder class allows for easier copying
                                  // and pointer semantics, as well as handling
                                  // destruction automatically.
   va_end(vlist);
 
-  StreamReader reader;
+  scanf_core::StdinReader reader;
   int retval = scanf_core::scanf_main(&reader, format, args);
   // This is done to avoid including stdio.h in the internals. On most systems
   // EOF is -1, so this will be transformed into just "return retval".