[libc-commits] [libc] 121c645 - [libc] add printf pointer conv

[Michael Jones via libc-commits]

Author: Michael Jones
Date: 2022-06-17T17:18:13-07:00
New Revision: 121c6454141d943ce2c886a2faea6781945c8a25

URL: https://github.com/llvm/llvm-project/commit/121c6454141d943ce2c886a2faea6781945c8a25
DIFF: https://github.com/llvm/llvm-project/commit/121c6454141d943ce2c886a2faea6781945c8a25.diff

LOG: [libc] add printf pointer conv

The pointer converter handles the %p conversion. It uses the hex
converter for most of the conversion.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D127995

Added: 
    libc/src/stdio/printf_core/ptr_converter.h

Modified: 
    libc/src/stdio/printf_core/CMakeLists.txt
    libc/src/stdio/printf_core/converter.cpp
    libc/src/stdio/printf_core/converter_atlas.h
    libc/test/src/stdio/printf_core/converter_test.cpp
    libc/test/src/stdio/sprintf_test.cpp

Removed: 
    


################################################################################
diff  --git a/libc/src/stdio/printf_core/CMakeLists.txt b/libc/src/stdio/printf_core/CMakeLists.txt
index f39fa2965de0..1f1db368cb17 100644
--- a/libc/src/stdio/printf_core/CMakeLists.txt
+++ b/libc/src/stdio/printf_core/CMakeLists.txt
@@ -62,6 +62,7 @@ add_object_library(
     char_converter.h
     int_converter.h
     hex_converter.h
+    ptr_converter.h
   DEPENDS
     .writer
     .core_structs

diff  --git a/libc/src/stdio/printf_core/converter.cpp b/libc/src/stdio/printf_core/converter.cpp
index 79e43d53cbed..609295195386 100644
--- a/libc/src/stdio/printf_core/converter.cpp
+++ b/libc/src/stdio/printf_core/converter.cpp
@@ -61,7 +61,7 @@ int convert(Writer *writer, const FormatSection &to_conv) {
   case 'n':
     // return convert_write_int(writer, to_conv);
   case 'p':
-    // return convert_pointer(writer, to_conv);
+    return convert_pointer(writer, to_conv);
   default:
     return writer->write(to_conv.raw_string, to_conv.raw_len);
   }

diff  --git a/libc/src/stdio/printf_core/converter_atlas.h b/libc/src/stdio/printf_core/converter_atlas.h
index 144be3383334..fe26060a7594 100644
--- a/libc/src/stdio/printf_core/converter_atlas.h
+++ b/libc/src/stdio/printf_core/converter_atlas.h
@@ -36,5 +36,6 @@
 // defines convert_write_int
 
 // defines convert_pointer
+#include "src/stdio/printf_core/ptr_converter.h"
 
 #endif // LLVM_LIBC_SRC_STDIO_PRINTF_CORE_CONVERTER_ATLAS_H

diff  --git a/libc/src/stdio/printf_core/ptr_converter.h b/libc/src/stdio/printf_core/ptr_converter.h
new file mode 100644
index 000000000000..6b1f3a30e8ba
--- /dev/null
+++ b/libc/src/stdio/printf_core/ptr_converter.h
@@ -0,0 +1,39 @@
+//===-- Pointer Converter for printf ----------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_STDIO_PRINTF_CORE_PTR_CONVERTER_H
+#define LLVM_LIBC_SRC_STDIO_PRINTF_CORE_PTR_CONVERTER_H
+
+#include "src/stdio/printf_core/converter_utils.h"
+#include "src/stdio/printf_core/core_structs.h"
+#include "src/stdio/printf_core/hex_converter.h"
+#include "src/stdio/printf_core/writer.h"
+
+namespace __llvm_libc {
+namespace printf_core {
+
+int inline convert_pointer(Writer *writer, const FormatSection &to_conv) {
+  if (to_conv.conv_val_ptr == (void *)(nullptr)) {
+    const char ZERO_STR[] = "(nullptr)";
+    // subtract 1 from sizeof to remove the null byte at the end.
+    RET_IF_RESULT_NEGATIVE(writer->write(ZERO_STR, sizeof(ZERO_STR) - 1));
+  } else {
+    FormatSection hex_conv;
+    hex_conv.has_conv = true;
+    hex_conv.conv_name = 'x';
+    hex_conv.flags = FormatFlags::ALTERNATE_FORM;
+    hex_conv.conv_val_raw = reinterpret_cast<uintptr_t>(to_conv.conv_val_ptr);
+    return convert_hex(writer, hex_conv);
+  }
+  return 0;
+}
+
+} // namespace printf_core
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_STDIO_PRINTF_CORE_PTR_CONVERTER_H

diff  --git a/libc/test/src/stdio/printf_core/converter_test.cpp b/libc/test/src/stdio/printf_core/converter_test.cpp
index d0025618ca31..d7c292394cb0 100644
--- a/libc/test/src/stdio/printf_core/converter_test.cpp
+++ b/libc/test/src/stdio/printf_core/converter_test.cpp
@@ -223,3 +223,23 @@ TEST(LlvmLibcPrintfConverterTest, HexConversion) {
   ASSERT_STREQ(str, "0x00000000123456ab");
   ASSERT_EQ(writer.get_chars_written(), 18);
 }
+
+TEST(LlvmLibcPrintfConverterTest, PointerConversion) {
+  char str[20];
+  __llvm_libc::printf_core::StringWriter str_writer(str);
+  __llvm_libc::printf_core::Writer writer(
+      reinterpret_cast<void *>(&str_writer),
+      __llvm_libc::printf_core::write_to_string);
+
+  __llvm_libc::printf_core::FormatSection section;
+  section.has_conv = true;
+  section.raw_string = "%p";
+  section.raw_len = 2;
+  section.conv_name = 'p';
+  section.conv_val_ptr = (void *)(0x123456ab);
+  __llvm_libc::printf_core::convert(&writer, section);
+
+  str_writer.terminate();
+  ASSERT_STREQ(str, "0x123456ab");
+  ASSERT_EQ(writer.get_chars_written(), 10);
+}

diff  --git a/libc/test/src/stdio/sprintf_test.cpp b/libc/test/src/stdio/sprintf_test.cpp
index 974674eb2ea4..4411216a1544 100644
--- a/libc/test/src/stdio/sprintf_test.cpp
+++ b/libc/test/src/stdio/sprintf_test.cpp
@@ -346,6 +346,22 @@ TEST(LlvmLibcSPrintfTest, HexConv) {
   ASSERT_STREQ(buff, "007F 0x1000000000 002   ");
 }
 
+TEST(LlvmLibcSPrintfTest, PointerConv) {
+  char buff[64];
+  int written;
+
+  written = __llvm_libc::sprintf(buff, "%p", nullptr);
+  EXPECT_EQ(written, 9);
+  ASSERT_STREQ(buff, "(nullptr)");
+
+  written = __llvm_libc::sprintf(buff, "%p", 0x1a2b3c4d);
+  EXPECT_EQ(written, 10);
+  ASSERT_STREQ(buff, "0x1a2b3c4d");
+
+  written = __llvm_libc::sprintf(buff, "%p", buff);
+  EXPECT_GT(written, 0);
+}
+
 #ifndef LLVM_LIBC_PRINTF_DISABLE_INDEX_MODE
 TEST(LlvmLibcSPrintfTest, IndexModeParsing) {
   char buff[64];