Merge "Implement __fsetlocking."
diff --git a/benchmarks/stdio_benchmark.cpp b/benchmarks/stdio_benchmark.cpp
index fe25d76..5658a50 100644
--- a/benchmarks/stdio_benchmark.cpp
+++ b/benchmarks/stdio_benchmark.cpp
@@ -17,6 +17,7 @@
#include "benchmark.h"
#include <stdio.h>
+#include <stdio_ext.h>
#define KB 1024
#define MB 1024*KB
@@ -29,6 +30,7 @@
static void ReadWriteTest(int iters, int chunk_size, Fn f, bool buffered) {
StopBenchmarkTiming();
FILE* fp = fopen("/dev/zero", "rw");
+ __fsetlocking(fp, FSETLOCKING_BYCALLER);
char* buf = new char[chunk_size];
StartBenchmarkTiming();
@@ -66,12 +68,22 @@
}
BENCHMARK(BM_stdio_fwrite_unbuffered)->AT_COMMON_SIZES;
-static void BM_stdio_fopen_fgets_fclose(int iters) {
+static void FopenFgetsFclose(int iters, bool no_locking) {
char buf[1024];
for (int i = 0; i < iters; ++i) {
FILE* fp = fopen("/proc/version", "re");
+ if (no_locking) __fsetlocking(fp, FSETLOCKING_BYCALLER);
fgets(buf, sizeof(buf), fp);
fclose(fp);
}
}
-BENCHMARK(BM_stdio_fopen_fgets_fclose);
+
+static void BM_stdio_fopen_fgets_fclose_locking(int iters) {
+ FopenFgetsFclose(iters, false);
+}
+BENCHMARK(BM_stdio_fopen_fgets_fclose_locking);
+
+static void BM_stdio_fopen_fgets_fclose_no_locking(int iters) {
+ FopenFgetsFclose(iters, true);
+}
+BENCHMARK(BM_stdio_fopen_fgets_fclose_no_locking);
diff --git a/libc/stdio/fileext.h b/libc/stdio/fileext.h
index 25b7bda..75230cd 100644
--- a/libc/stdio/fileext.h
+++ b/libc/stdio/fileext.h
@@ -33,6 +33,7 @@
#define _FILEEXT_H_
#include <pthread.h>
+#include <stdbool.h>
__BEGIN_DECLS
@@ -40,9 +41,10 @@
* file extension
*/
struct __sfileext {
- struct __sbuf _ub; /* ungetc buffer */
+ struct __sbuf _ub; /* ungetc buffer */
struct wchar_io_data _wcio; /* wide char io status */
- pthread_mutex_t _lock; /* file lock */
+ pthread_mutex_t _lock; /* file lock */
+ bool _stdio_handles_locking; /* __fsetlocking support */
};
#define _EXT(fp) ((struct __sfileext *)((fp)->_ext._base))
@@ -54,7 +56,8 @@
_UB(fp)._base = NULL; \
_UB(fp)._size = 0; \
WCIO_INIT(fp); \
- _FLOCK(fp).value = __PTHREAD_RECURSIVE_MUTEX_INIT_VALUE; \
+ _FLOCK(fp).value = __PTHREAD_RECURSIVE_MUTEX_INIT_VALUE; \
+ _EXT(fp)->_stdio_handles_locking = true; \
} while (0)
#define _FILEEXT_SETUP(f, fext) \
diff --git a/libc/stdio/local.h b/libc/stdio/local.h
index 46b11f1..7033eda 100644
--- a/libc/stdio/local.h
+++ b/libc/stdio/local.h
@@ -111,8 +111,8 @@
(fp)->_lb._base = NULL; \
}
-#define FLOCKFILE(fp) flockfile(fp)
-#define FUNLOCKFILE(fp) funlockfile(fp)
+#define FLOCKFILE(fp) if (_EXT(fp)->_stdio_handles_locking) flockfile(fp)
+#define FUNLOCKFILE(fp) if (_EXT(fp)->_stdio_handles_locking) funlockfile(fp)
#define FLOATING_POINT
#define PRINTF_WIDE_CHAR
diff --git a/libc/stdio/stdio_ext.cpp b/libc/stdio/stdio_ext.cpp
index bfdecb8..fea44f6 100644
--- a/libc/stdio/stdio_ext.cpp
+++ b/libc/stdio/stdio_ext.cpp
@@ -27,13 +27,10 @@
*/
#include <stdio_ext.h>
+#include <stdlib.h>
-#include <stdio.h>
#include "local.h"
-
-#define FSETLOCKING_QUERY 0
-#define FSETLOCKING_INTERNAL 1
-#define FSETLOCKING_BYCALLER 2
+#include "private/libc_logging.h"
size_t __fbufsize(FILE* fp) {
return fp->_bf._size;
@@ -76,11 +73,19 @@
fflush(NULL);
}
-int __fsetlocking(FILE*, int) {
- // We don't currently have an implementation that would obey this,
- // so make setting the state a no-op and always return "we handle locking for you".
- // http://b/17154740 suggests ways we could fix this.
- return FSETLOCKING_INTERNAL;
+int __fsetlocking(FILE* fp, int type) {
+ int old_state = _EXT(fp)->_stdio_handles_locking ? FSETLOCKING_INTERNAL : FSETLOCKING_BYCALLER;
+ if (type == FSETLOCKING_QUERY) {
+ return old_state;
+ }
+
+ if (type != FSETLOCKING_INTERNAL && type != FSETLOCKING_BYCALLER) {
+ // The API doesn't let us report an error, so blow up.
+ __libc_fatal("Bad type (%d) passed to __fsetlocking", type);
+ }
+
+ _EXT(fp)->_stdio_handles_locking = (type == FSETLOCKING_INTERNAL);
+ return old_state;
}
void clearerr_unlocked(FILE* fp) {
diff --git a/tests/stdio_ext_test.cpp b/tests/stdio_ext_test.cpp
index 950c7ed..c95cbbd 100644
--- a/tests/stdio_ext_test.cpp
+++ b/tests/stdio_ext_test.cpp
@@ -133,7 +133,10 @@
TEST(stdio_ext, __fsetlocking) {
FILE* fp = fopen("/proc/version", "r");
- // Android doesn't actually support the other modes.
+ ASSERT_EQ(FSETLOCKING_INTERNAL, __fsetlocking(fp, FSETLOCKING_QUERY));
+ ASSERT_EQ(FSETLOCKING_INTERNAL, __fsetlocking(fp, FSETLOCKING_BYCALLER));
+ ASSERT_EQ(FSETLOCKING_BYCALLER, __fsetlocking(fp, FSETLOCKING_QUERY));
+ ASSERT_EQ(FSETLOCKING_BYCALLER, __fsetlocking(fp, FSETLOCKING_INTERNAL));
ASSERT_EQ(FSETLOCKING_INTERNAL, __fsetlocking(fp, FSETLOCKING_QUERY));
fclose(fp);
}