diff options
| -rw-r--r-- | common/os_posix.cpp | 12 | ||||
| -rw-r--r-- | common/os_process.hpp | 26 | ||||
| -rw-r--r-- | common/trace_writer_local.cpp | 28 | ||||
| -rw-r--r-- | common/trace_writer_local.hpp | 8 |
4 files changed, 68 insertions, 6 deletions
diff --git a/common/os_posix.cpp b/common/os_posix.cpp index bd15bbac..5ec8b363 100644 --- a/common/os_posix.cpp +++ b/common/os_posix.cpp @@ -173,8 +173,16 @@ log(const char *format, ...) #ifdef ANDROID __android_log_vprint(ANDROID_LOG_DEBUG, "apitrace", format, ap); #else - vfprintf(stderr, format, ap); - fflush(stderr); + static FILE *log = NULL; + if (!log) { + // Duplicate stderr file descriptor, to prevent applications from + // redirecting our debug messages to somewhere else. + // + // Another alternative would be to log to /dev/tty when available. + log = fdopen(dup(STDERR_FILENO), "at"); + } + vfprintf(log, format, ap); + fflush(log); #endif va_end(ap); logging = false; diff --git a/common/os_process.hpp b/common/os_process.hpp index ba53408c..e1b1df17 100644 --- a/common/os_process.hpp +++ b/common/os_process.hpp @@ -33,6 +33,9 @@ #ifdef _WIN32 #include <windows.h> +#else +#include <sys/types.h> +#include <unistd.h> #endif #include "os.hpp" @@ -41,7 +44,26 @@ namespace os { -inline void +typedef +#ifdef _WIN32 + DWORD +#else + pid_t +#endif +ProcessId; + + +static inline ProcessId +getCurrentProcessId(void) { +#ifdef _WIN32 + return GetCurrentProcessId(); +#else + return getpid(); +#endif +} + + +static inline void setEnvironment(const char *name, const char *value) { #ifdef _WIN32 SetEnvironmentVariableA(name, value); @@ -51,7 +73,7 @@ setEnvironment(const char *name, const char *value) { } -inline void +static inline void unsetEnvironment(const char *name) { #ifdef _WIN32 SetEnvironmentVariableA(name, NULL); diff --git a/common/trace_writer_local.cpp b/common/trace_writer_local.cpp index 757e9c0f..d2ff3b5f 100644 --- a/common/trace_writer_local.cpp +++ b/common/trace_writer_local.cpp @@ -63,6 +63,8 @@ static void exceptionCallback(void) LocalWriter::LocalWriter() : acquired(0) { + os::log("apitrace: loaded\n"); + // Install the signal handlers as early as possible, to prevent // interfering with the application's signal handling. os::setExceptionCallback(exceptionCallback); @@ -71,6 +73,7 @@ LocalWriter::LocalWriter() : LocalWriter::~LocalWriter() { os::resetExceptionCallback(); + checkProcessId(); } void @@ -122,6 +125,8 @@ LocalWriter::open(void) { os::abort(); } + pid = os::getCurrentProcessId(); + #if 0 // For debugging the exception handler *((int *)0) = 0; @@ -133,10 +138,25 @@ static uintptr_t next_thread_num = 1; static OS_THREAD_SPECIFIC_PTR(void) thread_num; +void LocalWriter::checkProcessId(void) { + if (m_file->isOpened() && + os::getCurrentProcessId() != pid) { + // We are a forked child process that inherited the trace file, so + // create a new file. We can't call any method of the current + // file, as it may cause it to flush and corrupt the parent's + // trace, so we effectively leak the old file object. + m_file = File::createSnappy(); + // Don't want to open the same file again + os::unsetEnvironment("TRACE_FILE"); + open(); + } +} + unsigned LocalWriter::beginEnter(const FunctionSig *sig) { mutex.lock(); ++acquired; + checkProcessId(); if (!m_file->isOpened()) { open(); } @@ -185,8 +205,12 @@ void LocalWriter::flush(void) { } else { ++acquired; if (m_file->isOpened()) { - os::log("apitrace: flushing trace due to an exception\n"); - m_file->flush(); + if (os::getCurrentProcessId() != pid) { + os::log("apitrace: ignoring exception in child process\n"); + } else { + os::log("apitrace: flushing trace due to an exception\n"); + m_file->flush(); + } } --acquired; } diff --git a/common/trace_writer_local.hpp b/common/trace_writer_local.hpp index cc5dda01..815e3c0f 100644 --- a/common/trace_writer_local.hpp +++ b/common/trace_writer_local.hpp @@ -34,6 +34,7 @@ #include <stdint.h> #include "os_thread.hpp" +#include "os_process.hpp" #include "trace_writer.hpp" @@ -70,6 +71,13 @@ namespace trace { os::recursive_mutex mutex; int acquired; + /** + * ID of the processed that opened the trace file. + */ + os::ProcessId pid; + + void checkProcessId(); + public: /** * Should never called directly -- use localWriter singleton below |