Spanify FXSYS_IntToTwoHexChars() and FXSYS_IntToFourHexChars()
Pass in a fixed-size span of the required size in these functions,
instead of a pointer of unknown size. As a result, some UNSAFE_BUFFERS()
usage can go away.
While updating FXSYS_ToUTF16BE(), which this change affects, switch it
to use compile-time sizes for its span usage.
Bug: 42270715
Change-Id: I93d1a006840046afed7a1c48b0be18fafa2ad35b
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/126133
Reviewed-by: Thomas Sepez <tsepez@google.com>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
diff --git a/core/fpdfapi/parser/fpdf_parser_utility.cpp b/core/fpdfapi/parser/fpdf_parser_utility.cpp
index f82bfe4..441dfd1 100644
--- a/core/fpdfapi/parser/fpdf_parser_utility.cpp
+++ b/core/fpdfapi/parser/fpdf_parser_utility.cpp
@@ -132,7 +132,7 @@
if (ch >= 0x80 || PDFCharIsWhitespace(ch) || ch == '#' ||
PDFCharIsDelimiter(ch)) {
dest_buf[dest_len++] = '#';
- FXSYS_IntToTwoHexChars(ch, &dest_buf[dest_len]);
+ FXSYS_IntToTwoHexChars(ch, dest_buf.subspan(dest_len, 2u));
dest_len += 2;
continue;
}
diff --git a/core/fxcrt/fx_extension.cpp b/core/fxcrt/fx_extension.cpp
index c59a46a..45393e6 100644
--- a/core/fxcrt/fx_extension.cpp
+++ b/core/fxcrt/fx_extension.cpp
@@ -8,6 +8,8 @@
#include <wchar.h>
+#include <array>
+
#include "core/fxcrt/check.h"
#include "core/fxcrt/check_op.h"
#include "core/fxcrt/compiler_specific.h"
@@ -61,23 +63,18 @@
return dstStr;
}
-// TODO(tsepez): should be UNSAFE_BUFFER_USAGE.
-void FXSYS_IntToTwoHexChars(uint8_t n, char* buf) {
- static const char kHex[] = "0123456789ABCDEF";
- // SAFETY: range of uint8_t keeps indices in bound.
- UNSAFE_BUFFERS({
- buf[0] = kHex[n / 16];
- buf[1] = kHex[n % 16];
- });
+void FXSYS_IntToTwoHexChars(uint8_t n, pdfium::span<char, 2u> buf) {
+ static constexpr std::array<const char, 16> kHex = {
+ '0', '1', '2', '3', '4', '5', '6', '7',
+ '8', '9', 'A', 'B', 'C', 'D', 'E', 'F',
+ };
+ buf[0] = kHex[n / 16];
+ buf[1] = kHex[n % 16];
}
-// TODO(tsepez): This is UNSAFE_BUFFER_USAGE as well.
-void FXSYS_IntToFourHexChars(uint16_t n, char* buf) {
- // SAFETY: required from caller.
- UNSAFE_BUFFERS({
- FXSYS_IntToTwoHexChars(n / 256, buf);
- FXSYS_IntToTwoHexChars(n % 256, buf + 2);
- });
+void FXSYS_IntToFourHexChars(uint16_t n, pdfium::span<char, 4u> buf) {
+ FXSYS_IntToTwoHexChars(n / 256, buf.first<2u>());
+ FXSYS_IntToTwoHexChars(n % 256, buf.subspan<2u>());
}
pdfium::span<const char> FXSYS_ToUTF16BE(uint32_t unicode,
@@ -87,12 +84,12 @@
DCHECK(!pdfium::IsLowSurrogate(unicode));
if (unicode <= 0xFFFF) {
- FXSYS_IntToFourHexChars(unicode, buf.data());
- return buf.first(4u);
+ FXSYS_IntToFourHexChars(unicode, buf);
+ return buf.first<4u>();
}
pdfium::SurrogatePair surrogate_pair(unicode);
- FXSYS_IntToFourHexChars(surrogate_pair.high(), buf.data());
- FXSYS_IntToFourHexChars(surrogate_pair.low(), buf.subspan(4u).data());
+ FXSYS_IntToFourHexChars(surrogate_pair.high(), buf);
+ FXSYS_IntToFourHexChars(surrogate_pair.low(), buf.subspan<4u>());
return buf;
}
diff --git a/core/fxcrt/fx_extension.h b/core/fxcrt/fx_extension.h
index 27db9fc..593b560 100644
--- a/core/fxcrt/fx_extension.h
+++ b/core/fxcrt/fx_extension.h
@@ -115,8 +115,8 @@
return FXSYS_IsDecimalDigit(c) ? c - L'0' : 0;
}
-void FXSYS_IntToTwoHexChars(uint8_t n, char* buf);
-void FXSYS_IntToFourHexChars(uint16_t n, char* buf);
+void FXSYS_IntToTwoHexChars(uint8_t n, pdfium::span<char, 2u> buf);
+void FXSYS_IntToFourHexChars(uint16_t n, pdfium::span<char, 4u> buf);
// Converts `unicode` to a UTF16-BE hex string. Writes the string into `buf` and
// returns the portion of `buf` used to store the string. The returned span is
diff --git a/core/fxcrt/fx_extension_unittest.cpp b/core/fxcrt/fx_extension_unittest.cpp
index b040549..15e0879 100644
--- a/core/fxcrt/fx_extension_unittest.cpp
+++ b/core/fxcrt/fx_extension_unittest.cpp
@@ -84,33 +84,33 @@
}
TEST(fxcrt, FXSYSIntToTwoHexChars) {
- char buf[3] = {0};
+ char buf[2] = {0};
FXSYS_IntToTwoHexChars(0x0, buf);
- EXPECT_STREQ("00", buf);
+ EXPECT_THAT(buf, ElementsAre('0', '0'));
FXSYS_IntToTwoHexChars(0x9, buf);
- EXPECT_STREQ("09", buf);
+ EXPECT_THAT(buf, ElementsAre('0', '9'));
FXSYS_IntToTwoHexChars(0xA, buf);
- EXPECT_STREQ("0A", buf);
+ EXPECT_THAT(buf, ElementsAre('0', 'A'));
FXSYS_IntToTwoHexChars(0x8C, buf);
- EXPECT_STREQ("8C", buf);
+ EXPECT_THAT(buf, ElementsAre('8', 'C'));
FXSYS_IntToTwoHexChars(0xBE, buf);
- EXPECT_STREQ("BE", buf);
+ EXPECT_THAT(buf, ElementsAre('B', 'E'));
FXSYS_IntToTwoHexChars(0xD0, buf);
- EXPECT_STREQ("D0", buf);
+ EXPECT_THAT(buf, ElementsAre('D', '0'));
FXSYS_IntToTwoHexChars(0xFF, buf);
- EXPECT_STREQ("FF", buf);
+ EXPECT_THAT(buf, ElementsAre('F', 'F'));
}
TEST(fxcrt, FXSYSIntToFourHexChars) {
- char buf[5] = {0};
+ char buf[4] = {0};
FXSYS_IntToFourHexChars(0x0, buf);
- EXPECT_STREQ("0000", buf);
+ EXPECT_THAT(buf, ElementsAre('0', '0', '0', '0'));
FXSYS_IntToFourHexChars(0xA23, buf);
- EXPECT_STREQ("0A23", buf);
+ EXPECT_THAT(buf, ElementsAre('0', 'A', '2', '3'));
FXSYS_IntToFourHexChars(0xB701, buf);
- EXPECT_STREQ("B701", buf);
+ EXPECT_THAT(buf, ElementsAre('B', '7', '0', '1'));
FXSYS_IntToFourHexChars(0xFFFF, buf);
- EXPECT_STREQ("FFFF", buf);
+ EXPECT_THAT(buf, ElementsAre('F', 'F', 'F', 'F'));
}
TEST(fxcrt, FXSYSToUTF16BE) {
diff --git a/fxjs/xfa/cfxjse_formcalc_context.cpp b/fxjs/xfa/cfxjse_formcalc_context.cpp
index 59c65c3..a4efc18 100644
--- a/fxjs/xfa/cfxjse_formcalc_context.cpp
+++ b/fxjs/xfa/cfxjse_formcalc_context.cpp
@@ -523,13 +523,13 @@
ByteString bsGUID;
{
// Span's lifetime must end before ReleaseBuffer() below.
- pdfium::span<char> pBuf = bsGUID.GetBuffer(40);
+ pdfium::span<char> guid_span = bsGUID.GetBuffer(40);
size_t out_index = 0;
for (size_t i = 0; i < 16; ++i, out_index += 2) {
if (bSeparator && (i == 4 || i == 6 || i == 8 || i == 10)) {
- pBuf[out_index++] = L'-';
+ guid_span[out_index++] = L'-';
}
- FXSYS_IntToTwoHexChars(data[i], &pBuf[out_index]);
+ FXSYS_IntToTwoHexChars(data[i], guid_span.subspan(out_index, 2u));
}
}
bsGUID.ReleaseBuffer(bSeparator ? 36 : 32);
