[libc] Add printf error handling

libc/src/stdio/CMakeLists.txt

@@ -125,6 +125,9 @@ add_entrypoint_object(
   DEPENDS
     libc.src.stdio.printf_core.printf_main
     libc.src.stdio.printf_core.writer
+    libc.src.stdio.printf_core.core_structs
+    libc.src.stdio.printf_core.error_converter
+    libc.src.__support.libc_errno
 )
 
 add_entrypoint_object(
@@ -136,6 +139,9 @@ add_entrypoint_object(
   DEPENDS
     libc.src.stdio.printf_core.printf_main
     libc.src.stdio.printf_core.writer
+    libc.src.stdio.printf_core.core_structs
+    libc.src.stdio.printf_core.error_converter
+    libc.src.__support.libc_errno
 )
 
 add_entrypoint_object(
@@ -146,6 +152,9 @@ add_entrypoint_object(
     asprintf.h
   DEPENDS
     libc.src.stdio.printf_core.vasprintf_internal
+    libc.src.stdio.printf_core.core_structs
+    libc.src.stdio.printf_core.error_converter
+    libc.src.__support.libc_errno
 )
 
 add_entrypoint_object(
@@ -157,6 +166,8 @@ add_entrypoint_object(
   DEPENDS
     libc.src.stdio.printf_core.printf_main
     libc.src.stdio.printf_core.writer
+    libc.src.stdio.printf_core.core_structs
+    libc.src.stdio.printf_core.error_converter
 )
 
 add_entrypoint_object(
@@ -168,6 +179,9 @@ add_entrypoint_object(
   DEPENDS
     libc.src.stdio.printf_core.printf_main
     libc.src.stdio.printf_core.writer
+    libc.src.stdio.printf_core.core_structs
+    libc.src.stdio.printf_core.error_converter
+    libc.src.__support.libc_errno
 )
 
 add_entrypoint_object(
@@ -178,6 +192,9 @@ add_entrypoint_object(
     vasprintf.h
   DEPENDS
     libc.src.stdio.printf_core.vasprintf_internal
+    libc.src.stdio.printf_core.core_structs
+    libc.src.stdio.printf_core.error_converter
+    libc.src.__support.libc_errno
 )
 
 add_subdirectory(printf_core)

libc/src/stdio/asprintf.cpp

@@ -8,7 +8,10 @@
 
 #include "src/stdio/asprintf.h"
 #include "src/__support/arg_list.h"
+#include "src/__support/libc_errno.h"
 #include "src/__support/macros/config.h"
+#include "src/stdio/printf_core/core_structs.h"
+#include "src/stdio/printf_core/error_converter.h"
 #include "src/stdio/printf_core/vasprintf_internal.h"
 
 namespace LIBC_NAMESPACE_DECL {
@@ -22,8 +25,18 @@ LLVM_LIBC_FUNCTION(int, asprintf,
                                  // and pointer semantics, as well as handling
                                  // destruction automatically.
   va_end(vlist);
-  int ret = printf_core::vasprintf_internal(buffer, format, args);
-  return ret;
+  auto ret_val = printf_core::vasprintf_internal(buffer, format, args);
+  if (!ret_val.has_value()) {
+    libc_errno = printf_core::internal_error_to_errno(ret_val.error());
+    return -1;
+  }
+  if (ret_val.value() > cpp::numeric_limits<int>::max()) {
+    libc_errno =
+        printf_core::internal_error_to_errno(-printf_core::OVERFLOW_ERROR);
+    return -1;
+  }
+
+  return static_cast<int>(ret_val.value());
 }
 
 } // namespace LIBC_NAMESPACE_DECL

libc/src/stdio/baremetal/CMakeLists.txt

@@ -29,8 +29,11 @@ add_entrypoint_object(
   DEPENDS
     libc.src.stdio.printf_core.printf_main
     libc.src.stdio.printf_core.writer
+    libc.src.stdio.printf_core.error_converter
+    libc.src.stdio.printf_core.core_structs
     libc.src.__support.arg_list
     libc.src.__support.OSUtil.osutil
+    libc.src.__support.libc_errno
 )
 
 add_entrypoint_object(
@@ -87,8 +90,11 @@ add_entrypoint_object(
   DEPENDS
     libc.src.stdio.printf_core.printf_main
     libc.src.stdio.printf_core.writer
+    libc.src.stdio.printf_core.error_converter
+    libc.src.stdio.printf_core.core_structs
     libc.src.__support.arg_list
     libc.src.__support.OSUtil.osutil
+    libc.src.__support.libc_errno
 )
 
 add_entrypoint_object(

libc/src/stdio/baremetal/printf.cpp

@@ -9,8 +9,10 @@
 #include "src/stdio/printf.h"
 #include "src/__support/OSUtil/io.h"
 #include "src/__support/arg_list.h"
+#include "src/__support/libc_errno.h"
 #include "src/__support/macros/config.h"
 #include "src/stdio/printf_core/core_structs.h"
+#include "src/stdio/printf_core/error_converter.h"
 #include "src/stdio/printf_core/printf_main.h"
 #include "src/stdio/printf_core/writer.h"
 
@@ -42,13 +44,25 @@ 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_value()) {
+    libc_errno = printf_core::internal_error_to_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 = printf_core::internal_error_to_errno(-flushval);
+    return -1;
+  }
 
-  return retval;
+  if (retval.value() > cpp::numeric_limits<int>::max()) {
+    libc_errno =
+        printf_core::internal_error_to_errno(-printf_core::OVERFLOW_ERROR);
+    return -1;
+  }
+
+  return static_cast<int>(retval.value());
 }
 
 } // namespace LIBC_NAMESPACE_DECL

libc/src/stdio/baremetal/vprintf.cpp

@@ -9,8 +9,10 @@
 #include "src/stdio/vprintf.h"
 #include "src/__support/OSUtil/io.h"
 #include "src/__support/arg_list.h"
+#include "src/__support/libc_errno.h"
 #include "src/__support/macros/config.h"
 #include "src/stdio/printf_core/core_structs.h"
+#include "src/stdio/printf_core/error_converter.h"
 #include "src/stdio/printf_core/printf_main.h"
 #include "src/stdio/printf_core/writer.h"
 
@@ -40,13 +42,25 @@ 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);
+  auto retval = printf_core::printf_main(&writer, format, args);
+  if (!retval.has_value()) {
+    libc_errno = printf_core::internal_error_to_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 = printf_core::internal_error_to_errno(-flushval);
+    return -1;
+  }
 
-  return retval;
+  if (retval.value() > cpp::numeric_limits<int>::max()) {
+    libc_errno =
+        printf_core::internal_error_to_errno(-printf_core::OVERFLOW_ERROR);
+    return -1;
+  }
+
+  return static_cast<int>(retval.value());
 }
 
 } // namespace LIBC_NAMESPACE_DECL

libc/src/stdio/generic/CMakeLists.txt

@@ -394,6 +394,8 @@ list(APPEND fprintf_deps
       libc.hdr.types.FILE
       libc.src.__support.arg_list
       libc.src.stdio.printf_core.vfprintf_internal
+      libc.src.stdio.printf_core.core_structs
+      libc.src.stdio.printf_core.error_converter
 )
 
 if(LLVM_LIBC_FULL_BUILD)

libc/src/stdio/generic/fprintf.cpp

@@ -11,6 +11,8 @@
 #include "src/__support/File/file.h"
 #include "src/__support/arg_list.h"
 #include "src/__support/macros/config.h"
+#include "src/stdio/printf_core/core_structs.h"
+#include "src/stdio/printf_core/error_converter.h"
 #include "src/stdio/printf_core/vfprintf_internal.h"
 
 #include "hdr/types/FILE.h"
@@ -27,8 +29,18 @@ LLVM_LIBC_FUNCTION(int, fprintf,
                                  // and pointer semantics, as well as handling
                                  // destruction automatically.
   va_end(vlist);
-  int ret_val = printf_core::vfprintf_internal(stream, format, args);
-  return ret_val;
+  auto ret_val = printf_core::vfprintf_internal(stream, format, args);
+  if (!ret_val.has_value()) {
+    libc_errno = printf_core::internal_error_to_errno(ret_val.error());
+    return -1;
+  }
+  if (ret_val.value() > cpp::numeric_limits<int>::max()) {
+    libc_errno =
+        printf_core::internal_error_to_errno(-printf_core::OVERFLOW_ERROR);
+    return -1;
+  }
+
+  return static_cast<int>(ret_val.value());
 }
 
 } // namespace LIBC_NAMESPACE_DECL

libc/src/stdio/generic/printf.cpp

@@ -11,6 +11,8 @@
 #include "src/__support/File/file.h"
 #include "src/__support/arg_list.h"
 #include "src/__support/macros/config.h"
+#include "src/stdio/printf_core/core_structs.h"
+#include "src/stdio/printf_core/error_converter.h"
 #include "src/stdio/printf_core/vfprintf_internal.h"
 
 #include "hdr/types/FILE.h"
@@ -31,9 +33,19 @@ LLVM_LIBC_FUNCTION(int, printf, (const char *__restrict format, ...)) {
                                  // and pointer semantics, as well as handling
                                  // destruction automatically.
   va_end(vlist);
-  int ret_val = printf_core::vfprintf_internal(
+  auto ret_val = printf_core::vfprintf_internal(
       reinterpret_cast<::FILE *>(PRINTF_STDOUT), format, args);
-  return ret_val;
+  if (!ret_val.has_value()) {
+    libc_errno = printf_core::internal_error_to_errno(ret_val.error());
+    return -1;
+  }
+  if (ret_val.value() > cpp::numeric_limits<int>::max()) {
+    libc_errno =
+        printf_core::internal_error_to_errno(-printf_core::OVERFLOW_ERROR);
+    return -1;
+  }
+
+  return static_cast<int>(ret_val.value());
 }
 
 } // namespace LIBC_NAMESPACE_DECL

libc/src/stdio/generic/vfprintf.cpp

@@ -11,6 +11,8 @@
 #include "src/__support/File/file.h"
 #include "src/__support/arg_list.h"
 #include "src/__support/macros/config.h"
+#include "src/stdio/printf_core/core_structs.h"
+#include "src/stdio/printf_core/error_converter.h"
 #include "src/stdio/printf_core/vfprintf_internal.h"
 
 #include "hdr/types/FILE.h"
@@ -24,8 +26,18 @@ LLVM_LIBC_FUNCTION(int, vfprintf,
   internal::ArgList args(vlist); // This holder class allows for easier copying
                                  // and pointer semantics, as well as handling
                                  // destruction automatically.
-  int ret_val = printf_core::vfprintf_internal(stream, format, args);
-  return ret_val;
+  auto ret_val = printf_core::vfprintf_internal(stream, format, args);
+  if (!ret_val.has_value()) {
+    libc_errno = printf_core::internal_error_to_errno(ret_val.error());
+    return -1;
+  }
+  if (ret_val.value() > cpp::numeric_limits<int>::max()) {
+    libc_errno =
+        printf_core::internal_error_to_errno(-printf_core::OVERFLOW_ERROR);
+    return -1;
+  }
+
+  return static_cast<int>(ret_val.value());
 }
 
 } // namespace LIBC_NAMESPACE_DECL

libc/src/stdio/generic/vprintf.cpp

@@ -11,6 +11,8 @@
 #include "src/__support/File/file.h"
 #include "src/__support/arg_list.h"
 #include "src/__support/macros/config.h"
+#include "src/stdio/printf_core/core_structs.h"
+#include "src/stdio/printf_core/error_converter.h"
 #include "src/stdio/printf_core/vfprintf_internal.h"
 
 #include "hdr/types/FILE.h"
@@ -29,9 +31,19 @@ LLVM_LIBC_FUNCTION(int, vprintf,
   internal::ArgList args(vlist); // This holder class allows for easier copying
                                  // and pointer semantics, as well as handling
                                  // destruction automatically.
-  int ret_val = printf_core::vfprintf_internal(
+  auto ret_val = printf_core::vfprintf_internal(
       reinterpret_cast<::FILE *>(PRINTF_STDOUT), format, args);
-  return ret_val;
+  if (!ret_val.has_value()) {
+    libc_errno = printf_core::internal_error_to_errno(ret_val.error());
+    return -1;
+  }
+  if (ret_val.value() > cpp::numeric_limits<int>::max()) {
+    libc_errno =
+        printf_core::internal_error_to_errno(-printf_core::OVERFLOW_ERROR);
+    return -1;
+  }
+
+  return static_cast<int>(ret_val.value());
 }
 
 } // namespace LIBC_NAMESPACE_DECL

libc/src/stdio/printf_core/CMakeLists.txt

@@ -32,6 +32,17 @@ if(printf_config_copts)
   list(PREPEND printf_config_copts "COMPILE_OPTIONS")
 endif()
 
+if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
+  add_subdirectory(${LIBC_TARGET_OS})
+else()
+  add_subdirectory(generic)
+endif()
+
+set(target_error_converter libc.src.stdio.printf_core.${LIBC_TARGET_OS}.${LIBC_TARGET_OS}_error_converter)
+if(NOT TARGET ${target_error_converter})
+    set(target_error_converter libc.src.stdio.printf_core.generic.generic_error_converter)
+endif()
+
 add_header_library(
   printf_config
   HDRS
@@ -47,6 +58,7 @@ add_header_library(
     libc.include.inttypes
     libc.src.__support.CPP.string_view
     libc.src.__support.FPUtil.fp_bits
+    libc.hdr.errno_macros
 )
 
 add_header_library(
@@ -125,6 +137,7 @@ add_header_library(
     .writer
     .core_structs
     libc.src.__support.arg_list
+    libc.src.__support.error_or
 )
 
 add_header_library(
@@ -136,10 +149,20 @@ add_header_library(
     libc.hdr.func.free
     libc.hdr.func.realloc
     libc.src.__support.arg_list
+    libc.src.__support.error_or
     libc.src.stdio.printf_core.printf_main
     libc.src.stdio.printf_core.writer
 )
 
+add_header_library(
+  error_converter
+  HDRS
+    error_converter.h
+  DEPENDS
+    ${target_error_converter}
+    libc.src.__support.macros.properties.architectures
+)
+
 if(NOT (TARGET libc.src.__support.File.file) AND LLVM_LIBC_FULL_BUILD)
   # Not all platforms have a file implementation. If file is unvailable, and a
   # full build is requested, then we must skip all file based printf sections.
@@ -152,8 +175,10 @@ add_header_library(
     vfprintf_internal.h
   DEPENDS
     libc.src.__support.File.file
+    libc.src.__support.error_or
     libc.src.__support.arg_list
     libc.src.stdio.printf_core.printf_main
     libc.src.stdio.printf_core.writer
   ${use_system_file}
 )
+