[compiler-rt] [scudo] Add `__scudo_get_info` symbol to export stats to a buffer. (PR #130273)

[via llvm-commits]

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@@ -128,6 +128,52 @@ TEST(ScudoStringsTest, Padding) {
   testAgainstLibc<int>("%03d - %03d", -12, -1234);
 }
 
+TEST(ScudoStringsTest, CopyIntoNullBuffer) {
+  scudo::ScopedString Str;
+  Str.append("abc");
+  EXPECT_EQ(4U, Str.copyToBuffer(nullptr, 0));
+}
+
+TEST(ScudoStringsTest, CopyFromAnEmptyString) {
+  scudo::ScopedString Str;
+  char buf[256] = {'0', '1'};
+  EXPECT_EQ(1U, Str.copyToBuffer(buf, sizeof(buf)));
+  EXPECT_STREQ("", buf);
+  EXPECT_EQ(0, buf[0]); // Rest of the buffer remains unchanged.
+}
+
+TEST(ScudoStringsTest, CopyFromAnEmptyStringIntoZeroSizeBuffer) {
+  scudo::ScopedString Str;
+  char buf[256] = {'0', '1'};
+  EXPECT_EQ(1U, Str.copyToBuffer(buf, 0));
+  EXPECT_EQ('0', buf[0]); // Nothing changed because provided size is 0.
+}
+
+TEST(ScudoStringsTest, CopyIntoLargeEnoughBuffer) {
+  scudo::ScopedString Str;
+  Str.append("abc");
+  char buf[256] = {'0', '1', '2', '3', '4', '5'};
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piwicode wrote:

I forgot to check for overflow. Fixed.

https://github.com/llvm/llvm-project/pull/130273