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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:25:22 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:25:22 +0000
commitf6ad4dcef54c5ce997a4bad5a6d86de229015700 (patch)
tree7cfa4e31ace5c2bd95c72b154d15af494b2bcbef /src/runtime/cgo/gcc_android.c
parentInitial commit. (diff)
downloadgolang-1.22-f6ad4dcef54c5ce997a4bad5a6d86de229015700.tar.xz
golang-1.22-f6ad4dcef54c5ce997a4bad5a6d86de229015700.zip
Adding upstream version 1.22.1.upstream/1.22.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/runtime/cgo/gcc_android.c')
-rw-r--r--src/runtime/cgo/gcc_android.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/src/runtime/cgo/gcc_android.c b/src/runtime/cgo/gcc_android.c
new file mode 100644
index 0000000..7ea2135
--- /dev/null
+++ b/src/runtime/cgo/gcc_android.c
@@ -0,0 +1,90 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include <stdarg.h>
+#include <android/log.h>
+#include <pthread.h>
+#include <dlfcn.h>
+#include "libcgo.h"
+
+void
+fatalf(const char* format, ...)
+{
+ va_list ap;
+
+ // Write to both stderr and logcat.
+ //
+ // When running from an .apk, /dev/stderr and /dev/stdout
+ // redirect to /dev/null. And when running a test binary
+ // via adb shell, it's easy to miss logcat.
+
+ fprintf(stderr, "runtime/cgo: ");
+ va_start(ap, format);
+ vfprintf(stderr, format, ap);
+ va_end(ap);
+ fprintf(stderr, "\n");
+
+ va_start(ap, format);
+ __android_log_vprint(ANDROID_LOG_FATAL, "runtime/cgo", format, ap);
+ va_end(ap);
+
+ abort();
+}
+
+// Truncated to a different magic value on 32-bit; that's ok.
+#define magic1 (0x23581321345589ULL)
+
+// From https://android.googlesource.com/platform/bionic/+/refs/heads/android10-tests-release/libc/private/bionic_asm_tls.h#69.
+#define TLS_SLOT_APP 2
+
+// inittls allocates a thread-local storage slot for g.
+//
+// It finds the first available slot using pthread_key_create and uses
+// it as the offset value for runtime.tls_g.
+static void
+inittls(void **tlsg, void **tlsbase)
+{
+ pthread_key_t k;
+ int i, err;
+ void *handle, *get_ver, *off;
+
+ // Check for Android Q where we can use the free TLS_SLOT_APP slot.
+ handle = dlopen("libc.so", RTLD_LAZY);
+ if (handle == NULL) {
+ fatalf("inittls: failed to dlopen main program");
+ return;
+ }
+ // android_get_device_api_level is introduced in Android Q, so its mere presence
+ // is enough.
+ get_ver = dlsym(handle, "android_get_device_api_level");
+ dlclose(handle);
+ if (get_ver != NULL) {
+ off = (void *)(TLS_SLOT_APP*sizeof(void *));
+ // tlsg is initialized to Q's free TLS slot. Verify it while we're here.
+ if (*tlsg != off) {
+ fatalf("tlsg offset wrong, got %ld want %ld\n", *tlsg, off);
+ }
+ return;
+ }
+
+ err = pthread_key_create(&k, nil);
+ if(err != 0) {
+ fatalf("pthread_key_create failed: %d", err);
+ }
+ pthread_setspecific(k, (void*)magic1);
+ // If thread local slots are laid out as we expect, our magic word will
+ // be located at some low offset from tlsbase. However, just in case something went
+ // wrong, the search is limited to sensible offsets. PTHREAD_KEYS_MAX was the
+ // original limit, but issue 19472 made a higher limit necessary.
+ for (i=0; i<384; i++) {
+ if (*(tlsbase+i) == (void*)magic1) {
+ *tlsg = (void*)(i*sizeof(void *));
+ pthread_setspecific(k, 0);
+ return;
+ }
+ }
+ fatalf("inittls: could not find pthread key");
+}
+
+void (*x_cgo_inittls)(void **tlsg, void **tlsbase) = inittls;