From e5d05814ac964a37eb336fb5a743227e55e85a41 Mon Sep 17 00:00:00 2001 From: Kostya Kortchinsky Date: Wed, 9 Oct 2019 15:09:28 +0000 Subject: [scudo][standalone] Get statistics in a char buffer Summary: Following up on D68471, this CL introduces some `getStats` APIs to gather statistics in char buffers (`ScopedString` really) instead of printing them out right away. Ultimately `printStats` will just output the buffer, but that allows us to potentially do some work on the intermediate buffer, and can be used for a `mallocz` type of functionality. This allows us to pretty much get rid of all the `Printf` calls around, but I am keeping the function in for debugging purposes. This changes the existing tests to use the new APIs when required. I will add new tests as suggested in D68471 in another CL. Reviewers: morehouse, hctim, vitalybuka, eugenis, cferris Reviewed By: morehouse Subscribers: delcypher, #sanitizers, llvm-commits Tags: #llvm, #sanitizers Differential Revision: https://reviews.llvm.org/D68653 git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@374173 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/scudo/standalone/string_utils.cpp | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) (limited to 'lib/scudo/standalone/string_utils.cpp') diff --git a/lib/scudo/standalone/string_utils.cpp b/lib/scudo/standalone/string_utils.cpp index 22b4fbd74..5de8b57bf 100644 --- a/lib/scudo/standalone/string_utils.cpp +++ b/lib/scudo/standalone/string_utils.cpp @@ -208,9 +208,18 @@ int formatString(char *Buffer, uptr BufferLength, const char *Format, } void ScopedString::append(const char *Format, va_list Args) { - CHECK_LT(Length, String.size()); - formatString(String.data() + Length, String.size() - Length, Format, Args); - Length += strlen(String.data() + Length); + DCHECK_LT(Length, String.size()); + va_list ArgsCopy; + va_copy(ArgsCopy, Args); + // formatString doesn't currently support a null buffer or zero buffer length, + // so in order to get the resulting formatted string length, we use a one-char + // buffer. + char C[1]; + const uptr AdditionalLength = + static_cast(formatString(C, sizeof(C), Format, Args)) + 1; + String.resize(Length + AdditionalLength); + formatString(String.data() + Length, AdditionalLength, Format, ArgsCopy); + Length = strlen(String.data()); CHECK_LT(Length, String.size()); } @@ -226,7 +235,7 @@ FORMAT(1, 2) void Printf(const char *Format, ...) { va_list Args; va_start(Args, Format); - ScopedString Msg(512); + ScopedString Msg(1024); Msg.append(Format, Args); outputRaw(Msg.data()); va_end(Args); -- cgit v1.2.1