commit 61e618955b7b708824590794c2e8b18bd63ab3ed
author Tom Sepez <tsepez@chromium.org> Thu Nov 17 18:03:21 2022 +0000
committer Pdfium LUCI CQ <pdfium-scoped@luci-project-accounts.iam.gserviceaccount.com> Thu Nov 17 18:03:21 2022 +0000
tree b780932e7550e4b289aefa4173efa024b3308e7d
parent fe90654d88d53fe3206a60adef8fa4ed5628f191

Pass spans to ToString<T>().

Avoid some pointer arithmetic.

Then adjust callers to pass the same, until we reach a point where
c-style char[] arrays are being passed. These now silently convert
to spans rather than decaying to char* ptrs.

Change-Id: I1243a3f2ad398eeb65dfcf6643eb6f549e1d80b6
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/101490
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>

core/fxcrt/fx_string.cpp

diff --git a/core/fxcrt/fx_string.cpp b/core/fxcrt/fx_string.cpp
index 1c497ed..e661363 100644
--- a/core/fxcrt/fx_string.cpp
+++ b/core/fxcrt/fx_string.cpp
@@ -11,6 +11,7 @@
 #include "core/fxcrt/cfx_utf8decoder.h"
 #include "core/fxcrt/cfx_utf8encoder.h"
 #include "core/fxcrt/fx_extension.h"
+#include "core/fxcrt/span_util.h"
 #include "third_party/base/compiler_specific.h"
 #include "third_party/base/span.h"
 
@@ -86,7 +87,7 @@
 }
 
 template <class T>
-size_t ToString(T value, int (*round_func)(T), char* buf) {
+size_t ToString(T value, int (*round_func)(T), pdfium::span<char> buf) {
   buf[0] = '0';
   buf[1] = '\0';
   if (value == 0) {
@@ -117,7 +118,7 @@
   int i = scaled / scale;
   FXSYS_itoa(i, buf2, 10);
   size_t len = strlen(buf2);
-  memcpy(buf + buf_size, buf2, len);
+  fxcrt::spancpy(buf.subspan(buf_size), pdfium::make_span(buf2).first(len));
   buf_size += len;
   int fraction = scaled % scale;
   if (fraction == 0) {
@@ -143,7 +144,7 @@
   return StringToFloat(FX_UTF8Encode(wsStr).AsStringView());
 }
 
-size_t FloatToString(float f, char* buf) {
+size_t FloatToString(float f, pdfium::span<char> buf) {
   return ToString<float>(f, FXSYS_roundf, buf);
 }
 
@@ -155,7 +156,7 @@
   return StringToDouble(FX_UTF8Encode(wsStr).AsStringView());
 }
 
-size_t DoubleToString(double d, char* buf) {
+size_t DoubleToString(double d, pdfium::span<char> buf) {
   return ToString<double>(d, FXSYS_round, buf);
 }
 

core/fxcrt/fx_string.h

diff --git a/core/fxcrt/fx_string.h b/core/fxcrt/fx_string.h
index b43b899..41d73e4 100644
--- a/core/fxcrt/fx_string.h
+++ b/core/fxcrt/fx_string.h
@@ -13,6 +13,7 @@
 
 #include "core/fxcrt/bytestring.h"
 #include "core/fxcrt/widestring.h"
+#include "third_party/base/span.h"
 
 constexpr uint32_t FXBSTR_ID(uint8_t c1, uint8_t c2, uint8_t c3, uint8_t c4) {
   return static_cast<uint32_t>(c1) << 24 | static_cast<uint32_t>(c2) << 16 |
@@ -24,11 +25,11 @@
 
 float StringToFloat(ByteStringView str);
 float StringToFloat(WideStringView wsStr);
-size_t FloatToString(float f, char* buf);
+size_t FloatToString(float f, pdfium::span<char> buf);
 
 double StringToDouble(ByteStringView str);
 double StringToDouble(WideStringView wsStr);
-size_t DoubleToString(double d, char* buf);
+size_t DoubleToString(double d, pdfium::span<char> buf);
 
 namespace fxcrt {
 

core/fxcrt/fx_string_unittest.cpp

diff --git a/core/fxcrt/fx_string_unittest.cpp b/core/fxcrt/fx_string_unittest.cpp
index 87891c1..2619864 100644
--- a/core/fxcrt/fx_string_unittest.cpp
+++ b/core/fxcrt/fx_string_unittest.cpp
@@ -6,17 +6,18 @@
 
 #include "core/fxcrt/fx_string.h"
 #include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/base/span.h"
 
-char* TerminatedFloatToString(float value, char* buf) {
+char* TerminatedFloatToString(float value, pdfium::span<char> buf) {
   size_t buflen = FloatToString(value, buf);
   buf[buflen] = '\0';
-  return buf;
+  return buf.data();
 }
 
-char* TerminatedDoubleToString(double value, char* buf) {
+char* TerminatedDoubleToString(double value, pdfium::span<char> buf) {
   size_t buflen = DoubleToString(value, buf);
   buf[buflen] = '\0';
-  return buf;
+  return buf.data();
 }
 
 TEST(fxstring, FX_UTF8Encode) {