Baremetal stuff

Author: mleleszi

libc/src/stdio/baremetal/printf.cpp

@@ -42,13 +42,24 @@ LLVM_LIBC_FUNCTION(int, printf, (const char *__restrict format, ...)) {
       buffer, BUFF_SIZE, &stdout_write_hook, nullptr);
   printf_core::Writer<printf_core::WriteMode::FLUSH_TO_STREAM> writer(wb);
 
-  int retval = printf_core::printf_main(&writer, format, args);
+  auto retval = printf_core::printf_main(&writer, format, args);
+  if (retval.has_error()) {
+    libc_errno = retval.error;
+    return -1;
+  }
 
   int flushval = wb.overflow_write("");
-  if (flushval != printf_core::WRITE_OK)
-    retval = flushval;
-    
-  return retval;
+  if (flushval != printf_core::WRITE_OK) {
+    libc_errno = -flushval;
+    return -1;
+  }
+
+  if (retval.value >= cpp::numeric_limits<int>::max()) {
+    libc_errno = EOVERFLOW;
+    return -1;
+  }
+
+  return static_cast<int>(retval.value);  
 }
 
 } // namespace LIBC_NAMESPACE_DECL

libc/src/stdio/baremetal/vprintf.cpp

@@ -40,13 +40,25 @@ LLVM_LIBC_FUNCTION(int, vprintf,
       buffer, BUFF_SIZE, &stdout_write_hook, nullptr);
   printf_core::Writer<printf_core::WriteMode::FLUSH_TO_STREAM> writer(wb);
 
-  int retval = printf_core::printf_main(&writer, format, args); // TODO baremetal stuff
+  auto retval = printf_core::printf_main(&writer, format, args);
+  if (retval.has_error()) {
+    libc_errno = retval.error;
+    return -1;
+  }
 
   int flushval = wb.overflow_write("");
-  if (flushval != printf_core::WRITE_OK)
-    retval = flushval;
+  if (flushval != printf_core::WRITE_OK) {
+    libc_errno = -flushval;
+    return -1;
+  
+  }
 
-  return retval;
+  if (retval.value >= cpp::numeric_limits<int>::max()) {
+    libc_errno = EOVERFLOW;
+    return -1;
+  }
+
+  return static_cast<int>(retval.value);
 }
 
 } // namespace LIBC_NAMESPACE_DECL

libc/src/stdio/printf_core/vfprintf_internal.h

@@ -78,6 +78,10 @@ LIBC_INLINE PrintfResult vfprintf_internal(::FILE *__restrict stream,
   Writer writer(wb);
   internal::flockfile(stream);
   auto retval = printf_main(&writer, format, args);
+  if (retval.has_error()) {
+    internal::funlockfile(stream);
+    return retval;
+  }
   int flushval = wb.overflow_write("");
   if (flushval != WRITE_OK)
     retval.error = -flushval;